Tellurium: A new sensitive test

USGS Publications Warehouse

Lakin, H.W.; Thompson, C.E.

1963-01-01

A new, extremely sensitive method for the quantitative determination of tellurium is based on the induced precipitation of elemental gold from a 6N HCl solution containing gold chloride, cupric chloride, and hypophosphorous acid; the amount of gold reduced is proportional to the amount of tellurium present. As little as 1 nanogram (1 ?? 70-9 g) of tellurium gives a measurable reaction with 1 mg of gold in 50 ml of solution.

Selective inhibition of Zn(2+)-glycerophosphocholine cholinephosphodiesterase by tellurium tetrachloride.

PubMed Central

Sok, D E; Kim, M R

1992-01-01

A Zn(2+)-glycerophosphocholine cholinephosphodiesterase (EC 3.1.4.38) purified from mouse brain was found to be reversibly inhibited by tellurium tetrachloride. This effect was characterized by a competitive pattern of inhibition, with apparent Ki values of 0.7 microM and 1.5 microM for the hydrolysis of p-nitrophenylphosphocholine and glycerophosphocholine respectively. Interestingly, the inhibitory effect of tellurium tetrachloride was found to be greatly potentiated by tetramethylammonium salt, indicative of a synergistic interaction between the two compounds. Additionally, it was observed that the effect of tellurium tetrachloride was not affected by a number of other metal ions, and was more pronounced at neutral pH, suggesting that the inhibitory role of the tellurium tetrachloride may be of importance under physiological conditions. Thus Zn(2+)-glycerophosphocholine cholinephosphodiesterase is proposed to be one of the target enzymes which is susceptible to the inhibitory effect of tellurium tetrachloride. PMID:1320372

Tellurium: providing a bright future for solar energy

USGS Publications Warehouse

Goldfarb, Richard J.

2015-01-01

Because of its low abundance, little is known about environmental baseline concentrations for tellurium or its toxic effect on humans and ecosystems. Human exposure to tellurium can lead to a garlic odor on the breath, nausea, and eventual respiratory problems.

Tellurium-containing polymer micelles: competitive-ligand-regulated coordination responsive systems.

PubMed

Cao, Wei; Gu, Yuwei; Meineck, Myriam; Li, Tianyu; Xu, Huaping

2014-04-02

Nanomaterials capable of achieving tunable cargo release kinetics are of significance in a fundamental sense and various biological or medical applications. We report a competitive coordination system based on a novel tellurium-containing polymer and its ligand-regulated release manners. Tellurium was introduced to water-soluble polymers for the first time as drug delivery vehicles. The coordination chemistry between platinum and tellurium was designed to enable the load of platinum-based drugs. Through the competitive coordination of biomolecules, the drugs could be released in a controlled manner. Furthermore, the release kinetics could be modulated by the competitive ligands involved due to their different coordination ability. This tellurium-containing polymer may enrich the family of delivery systems and provide a new platform for future biomedical nanotechnologies.

Flame and flameless atomic-absorption determination of tellurium in geological materials

USGS Publications Warehouse

Chao, T.T.; Sanzolone, R.F.; Hubert, A.E.

1978-01-01

The sample is digested with a solution of hydrobromic acid and bromine and the excess of bromine is expelled. After dilution of the solution to approximately 3 M in hydrobromic acid, ascorbic acid is added to reduce iron(III) before extraction of tellurium into methyl isobutyl ketone (MIBK). An oxidizing air-acetylene flame is used to determine tellurium in the 0.1-20 ppm range. For samples containing 4-200 ppb of tellurium, a carbon-rod atomizer is used after the MIBK extract has been washed with 0.5 M hydrobromic acid to remove the residual iron. The flame procedure is useful for rapid preliminary monitoring, and the flameless procedure can determine tellurium at very low concentrations. ?? 1978.

Lithium-tellurium bimetallic cell has increased voltage

NASA Technical Reports Server (NTRS)

Cairns, E. J.; Rogers, G. L.; Shimotake, H.

1968-01-01

Lithium-tellurium secondary cell with a fused lithium halide electrolyte, tested in the temperature range 467 degrees to 500 degrees C, showed improvement over the sodium bismuth cell. The voltage of this bimetallic cell was increased by using the more electropositive anode material, lithium, and the more electronegative cathode material, tellurium.

DETECTION OF THE SECOND r-PROCESS PEAK ELEMENT TELLURIUM IN METAL-POOR STARS ,

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

Roederer, Ian U.; Lawler, James E.; Cowan, John J.

2012-03-15

Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, we detect neutral tellurium in three metal-poor stars enriched by products of r-process nucleosynthesis, BD +17 3248, HD 108317, and HD 128279. Tellurium (Te, Z = 52) is found at the second r-process peak (A Almost-Equal-To 130) associated with the N = 82 neutron shell closure, and it has not been detected previously in Galactic halo stars. The derived tellurium abundances match the scaled solar system r-process distribution within the uncertainties, confirming the predicted second peak r-process residuals. These results suggest that tellurium ismore » predominantly produced in the main component of the r-process, along with the rare earth elements.« less

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

Manouchehrian, M.; Larijani, M.M., E-mail: mmojtahedfr@yahooo.com; Elahi, S.M.

Highlights: • Tellurium thin films were prepared by thermal evaporation technique. • Tellurium thin films showed excellent gas-sensing properties to H{sub 2}S at room temperature. • Tellurium showed a remarkably enhanced response to H{sub 2}S gas under UV irradiation. • The reason of the enhanced response by UV irradiation was discussed. - Abstract: In this research, tellurium thin films were investigated for use as hydrogen sulfide gas sensors. To this end, a tellurium thin film has been deposited on Al{sub 2}O{sub 3} substrates by thermal evaporation, and the influence of thickness on the sensitivity of the tellurium thin film formore » measuring H{sub 2}S gas is studied. XRD patterns indicate that as the thickness increases, the crystallization improves. Observing the images obtained by SEM, it is seen that the grain size increases as the thickness increases. Studying the effect of thickness on H{sub 2}S gas measurement, it became obvious that as the thickness increases, the sensitivity decreases and the response and recovery times increase. To improve the response and recovery times of the tellurium thin film for measuring H{sub 2}S gas, the influence of UV radiation while measuring H{sub 2}S gas was also investigated. The results indicate that the response and recovery times strongly decrease using UV radiation.« less

Determination of the absolute chirality of tellurium using resonant diffraction with circularly polarized x-rays.

PubMed

Tanaka, Y; Collins, S P; Lovesey, S W; Matsumami, M; Moriwaki, T; Shin, S

2010-03-31

Many proteins, sugars and pharmaceuticals crystallize into two forms that are mirror images of each other (enantiomers) like our right and left hands. Tellurium is one enantiomer having a space group pair, P3(1)21 (right-handed screw) and P3(2)21 (left-handed screw). X-ray diffraction with dispersion correction terms has been playing an important role in determining the handedness of enantiomers for a long time. However, this approach is not applicable for an elemental crystal such as tellurium or selenium. We have demonstrated that positive and negative circularly polarized x-rays at the resonant energy of tellurium can be used to absolutely distinguish right from left tellurium. This method is applicable to chiral motifs that occur in biomolecules, liquid crystals, ferroelectrics and antiferroelectrics, multiferroics, etc.

Near-infrared light stimuli-responsive synergistic therapy nanoplatforms based on the coordination of tellurium-containing block polymer and cisplatin for cancer treatment.

PubMed

Li, Feng; Li, Tianyu; Cao, Wei; Wang, Lu; Xu, Huaping

2017-07-01

Cisplatin (CDDP) has received worldwide approval for clinical use in the past decades. However, its development in cancer chemotherapy was overshadowed by severe side effects and drug resistance. Herein, we developed a CDDP drug delivery system with high encapsulation efficiency and near-infrared light stimuli-responsive drug release properties based on the coordination of novel tellurium-containing block polymer (PEG-PUTe-PEG) and CDDP. The nanocarriers made from PEG-PUTe-PEG were loaded with CDDP and indocyanine green (ICG) simultaneously. The coordination chemistry between CDDP and tellurium guaranteed the nanocarrier a high stability in plasma and prolonged circulation time in vivo by reducing possible penetration of water molecule into the nanoparticles. Under the stimuli of a near-infrared laser, an amount of ROS can be generated by irradiation of ICG. The tellurium is easily oxidized by ROS because of the low electronegativity of tellurium. The CDDP could be rapidly released from the nanocarriers along with the oxidation of the tellurium at the tumor sites as the oxidized tellurium will weaken the coordination interaction with CDDP. In addition, the encapsulated ICG played a synergistic antitumor effect through photothermal effect with mild laser irradiation. The integrated strategy achieved higher antitumor efficacy and showed minimal side effects compared with the CDDP alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

Understanding the Chemical Reactivity of Phosphonium-Based Ionic Liquids with Tellurium.

PubMed

Zhang, Tao; Schwedtmann, Kai; Weigand, Jan J; Doert, Thomas; Ruck, Michael

2018-05-15

The chemical reactivity of phosphonium based ionic liquids (ILs) towards tellurium at temperatures above 220 °C was systematically investigated by a series of dissolution experiments, tracking the solute tellurium species by nuclear magnetic resonance, and characterizing the reaction products by X-ray diffraction and scanning electron microscopy. The initial step is the thermal elimination of an alkyl group of the phosphonium cation of the ILs, most probably via an S N 2 mechanism. The addition of tellurium follows to form trialkylphosphane tellurides as evidenced by 31 P and 125 Te NMR spectroscopic experiments. The trialkylphosphane tellurides can serve as a tellurium reservoir for the formation of metal tellurides, like Bi 2 Te 3 and Ag 2 Te. It was observed that trihexyltetradecylphosphonium chloride ([P 6 6 6 14 ]Cl) shows a very weak reactivity that is reflected by a low solubility of tellurium, while trihexyltetradecylphosphonium dicyanamide/decanoate ([P 6 6 6 14 ][N(CN) 2 ]/[P 6 6 6 14 ][decanoate]) and tetrabutylphosphonium decanoate ([P 4 4 4 4 ][decanoate]) dissolve tellurium to a much higher extent. We attribute these observations to the different Lewis basicity of the anions of the ILs as main influencing factor. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bacteria form tellurium nanocrystals

USGS Publications Warehouse

Oremland, R.S.

2007-01-01

A team of researchers have found two bacterial species that produce tellurium oxyanions as respiratory electron acceptors for growth, leaving elemental tellurium in the form of nanoparticles. The crystals from the two organisms exhibit distinctively different structures. Bacillus selenitireducens initially forms nanorods that cluster together to form rosettes. Sulfurospirillum barnesii forms irregularly-shaped nanospheres that coalesce into larger composite aggregates.

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

Palomba, M., E-mail: mariano.palomba@cnr.it; Carotenuto, G.; Binetti, S.

Owing to the very brittle nature of the tellurium powder, nanoscopic grains with average size of 4.8 nm were produced by dry vibration milling technique using a Mixer mill apparatus. A novel material was obtained by binding the nanosized tellurium grains with poly(methyl methacrylate) (PMMA). The morphology, elemental composition, and structural properties of Te/PMMA films were investigated. The prepared material was composed of hexagonal tellurium and α-phase of tellurium oxide. The electrical properties of the films were studied in dark condition and under white light illumination varying the optical power density from 10 to 170 mW/cm{sup 2} and turning onmore » and off the light cyclically.« less

Simultaneously discrete biomineralization of magnetite and tellurium nanocrystals in magnetotactic bacteria.

PubMed

Tanaka, Masayoshi; Arakaki, Atsushi; Staniland, Sarah S; Matsunaga, Tadashi

2010-08-01

Magnetotactic bacteria synthesize intracellular magnetosomes comprising membrane-enveloped magnetite crystals within the cell which can be manipulated by a magnetic field. Here, we report the first example of tellurium uptake and crystallization within a magnetotactic bacterial strain, Magnetospirillum magneticum AMB-1. These bacteria independently crystallize tellurium and magnetite within the cell. This is also highly significant as tellurite (TeO(3)(2-)), an oxyanion of tellurium, is harmful to both prokaryotes and eukaryotes. Additionally, due to its increasing use in high-technology products, tellurium is very precious and commercially desirable. The use of microorganisms to recover such molecules from polluted water has been considered as a promising bioremediation technique. However, cell recovery is a bottleneck in the development of this approach. Recently, using the magnetic property of magnetotactic bacteria and a cell surface modification technology, the magnetic recovery of Cd(2+) adsorbed onto the cell surface was reported. Crystallization within the cell enables approximately 70 times more bioaccumulation of the pollutant per cell than cell surface adsorption, while utilizing successful recovery with a magnetic field. This fascinating dual crystallization of magnetite and tellurium by magnetotactic bacteria presents an ideal system for both bioremediation and magnetic recovery of tellurite.

Simultaneously Discrete Biomineralization of Magnetite and Tellurium Nanocrystals in Magnetotactic Bacteria▿

PubMed Central

Tanaka, Masayoshi; Arakaki, Atsushi; Staniland, Sarah S.; Matsunaga, Tadashi

2010-01-01

Magnetotactic bacteria synthesize intracellular magnetosomes comprising membrane-enveloped magnetite crystals within the cell which can be manipulated by a magnetic field. Here, we report the first example of tellurium uptake and crystallization within a magnetotactic bacterial strain, Magnetospirillum magneticum AMB-1. These bacteria independently crystallize tellurium and magnetite within the cell. This is also highly significant as tellurite (TeO32−), an oxyanion of tellurium, is harmful to both prokaryotes and eukaryotes. Additionally, due to its increasing use in high-technology products, tellurium is very precious and commercially desirable. The use of microorganisms to recover such molecules from polluted water has been considered as a promising bioremediation technique. However, cell recovery is a bottleneck in the development of this approach. Recently, using the magnetic property of magnetotactic bacteria and a cell surface modification technology, the magnetic recovery of Cd2+ adsorbed onto the cell surface was reported. Crystallization within the cell enables approximately 70 times more bioaccumulation of the pollutant per cell than cell surface adsorption, while utilizing successful recovery with a magnetic field. This fascinating dual crystallization of magnetite and tellurium by magnetotactic bacteria presents an ideal system for both bioremediation and magnetic recovery of tellurite. PMID:20581185

A recycling model of the biokinetics of systemic tellurium.

PubMed

Giussani, Augusto

2014-11-01

To develop a compartmental model of the systemic biokinetics of tellurium required for calculating the internal dose and interpreting bioassay measurements after incorporation of radioactive tellurium. The compartmental model for tellurium was developed with the software SAAM II v. 2.0 (©The Epsilon Group, Charlottesville, Virginia, USA). Model parameters were determined on the basis of published retention and excretion data in humans and animals. The model consists of two blood compartments, one compartment each for liver, kidneys, thyroid, four compartments for bone tissues and a generic compartment for the soft tissues. The model predicts a rapid urinary excretion of systemic tellurium: 45% in the first 24 h and 84% after 50 d. Faecal excretion amounts to 0.4% after 3 d and 9% after 50 d. Whole body retention is 55% after one day, and 2.8% after 100 d. These values as well as the retained fractions in the single organs are reasonably consistent with the available human and animal data (studies with swine and guinea pigs). The proposed model gives a realistic description of the available biokinetic data for tellurium and will be adopted by the International Commission on Radiological Protection for applications in internal dosimetry.

Optimization of scintillator loading with the tellurium-130 isotope for long-term stability

NASA Astrophysics Data System (ADS)

Duhamel, Lauren; Song, Xiaoya; Goutnik, Michael; Kaptanoglu, Tanner; Klein, Joshua; SNO+ Collaboration

2017-09-01

Tellurium-130 was selected as the isotope for the SNO + neutrinoless double beta decay search, as 130Te decays to 130Xe via double beta decay. Linear alkyl benzene(LAB) is the liquid scintillator for the SNO + experiment. To load tellurium into scintillator, it is combined with 1,2-butanediol to form an organometallic complex, commonly called tellurium butanediol (TeBD). This study focuses on maximizing the percentage of tellurium loaded into scintillator and evaluates the complex's long-term stability. Studies on the effect of nucleation due to imperfections in the detector's surface and external particulates were employed by filtration and induced nucleation. The impact of water on the stability of TeBD complex was evaluated by liquid-nitrogen sparging, variability in pH and induced humidity. Alternative loading methods were evaluated, including the addition of stability-inducing organic compounds. Samples of tellurium-loaded scintillator were synthesized, treated, and consistently monitored in a controlled environment. It was found that the hydronium ions cause precipitation in the loaded scintillator, demonstrating that water has a detrimental effect on long-term stability. Optimization of loaded scintillator stability can contribute to the SNO + double beta decay search.

Therapeutic potential of selenium and tellurium compounds: opportunities yet unrealised.

PubMed

Tiekink, Edward R T

2012-06-07

Despite being disparaged for their malodorous and toxic demeanour, compounds of selenium, a bio-essential element, and tellurium, offer possibilities as therapeutic agents. Herein, their potential use as drugs, for example, as anti-viral, anti-microbial, anti-inflammatory agents, etc., will be surveyed along with a summary of the established biological functions of selenium. The natural biological functions of tellurium remain to be discovered.

Phenylethynyl-butyltellurium inhibits the sulfhydryl enzyme Na+, K+ -ATPase: an effect dependent on the tellurium atom.

PubMed

Quines, Caroline B; Rosa, Suzan G; Neto, José S S; Zeni, Gilson; Nogueira, Cristina W

2013-11-01

Organotellurium compounds are known for their toxicological effects. These effects may be associated with the chemical structure of these compounds and the oxidation state of the tellurium atom. In this context, 2-phenylethynyl-butyltellurium (PEBT) inhibits the activity of the sulfhydryl enzyme, δ-aminolevulinate dehydratase. The present study investigated on the importance of the tellurium atom in the PEBT ability to oxidize mono- and dithiols of low molecular weight and sulfhydryl enzymes in vitro. PEBT, at high micromolar concentrations, oxidized dithiothreitol (DTT) and inhibited cerebral Na(+), K(+)-ATPase activity, but did not alter the lactate dehydrogenase activity. The inhibition of cerebral Na(+), K(+)-ATPase activity was completely restored by DTT. By contrast, 2-phenylethynyl-butyl, a molecule without the tellurium atom, neither oxidized DTT nor altered the Na(+), K(+)-ATPase activity. In conclusion, the tellurium atom of PEBT is crucial for the catalytic oxidation of sulfhydryl groups from thiols of low molecular weight and from Na(+), K(+)-ATPase.

Rapid determination of nanogram amounts of tellurium in silicate rocks

USGS Publications Warehouse

Greenland, L.P.; Campbell, E.Y.

1976-01-01

A hydride-generation flameless atomic-absorption technique is used to determine as little as 5 ng g-1 tellurium in 0.25 g of silicate rock. After acid decomposition of the sample, tellurium hydride is generated with sodium borohydride and the vapor passed directly to a resistance-heated quartz cell mounted in an atomic-absorption spectrophotometer. Analyses of 11 U.S. Geological Survey standard rocks are presented. ?? 1976.

Tellurium content of marine manganese oxides and other manganese oxides

USGS Publications Warehouse

Lakin, H.W.; Thompson, C.E.; Davidson, D.F.

1963-01-01

Tellurium in amounts ranging from 5 to 125 parts per million was present in all of 12 samples of manganese oxide nodules from the floor of the Pacific and Indian oceans. These samples represent the first recognized points of high tellurium concentration in a sedimentary cycle. The analyses may lend support to the theory that the minor-element content of seafloor manganese nodules is derived from volcanic emanations.

Tellurium-Impregnated Porous Cobalt-Doped Carbon Polyhedra as Superior Cathodes for Lithium-Tellurium Batteries.

PubMed

He, Jiarui; Lv, Weiqiang; Chen, Yuanfu; Wen, Kechun; Xu, Chen; Zhang, Wanli; Li, Yanrong; Qin, Wu; He, Weidong

2017-08-22

Lithium-tellurium (Li-Te) batteries are attractive for energy storage owing to their high theoretical volumetric capacity of 2621 mAh cm -3 . In this work, highly nanoporous cobalt and nitrogen codoped carbon polyhedra (C-Co-N) derived from a metal-organic framework (MOF) is synthesized and employed as tellurium host for Li-Te batteries. The Te@C-Co-N cathode with a high Te loading of 77.2 wt % exhibits record-breaking electrochemical performances including an ultrahigh initial capacity of 2615.2 mAh cm -3 approaching the theoretical capacity of Te (2621 mAh cm -3 ), a superior cycling stability with a high capacity retention of 93.6%, a ∼99% Columbic efficiency after 800 cycles as well as rate capacities of 2160, 1327.6, and 894.8 mAh cm -3 at 4, 10, and 20 C, respectively. The redox chemistry of tellurium is revealed by in operando Raman spectroscopic analysis and density functional theory simulations. The results illustrate that the performances are attributed to the highly conductive C-Co-N matrix with an advantageous structure of abundant micropores, which provides highly efficient channels for electron transfer and ionic diffusion as well as sufficient surface area to efficiently host tellurium while mitigating polytelluride dissolution and suppressing volume expansion.

Tellurium stable isotope fractionation in chondritic meteorites and some terrestrial samples

NASA Astrophysics Data System (ADS)

Fehr, Manuela A.; Hammond, Samantha J.; Parkinson, Ian J.

2018-02-01

New methodologies employing a 125Te-128Te double-spike were developed and applied to obtain high precision mass-dependent tellurium stable isotope data for chondritic meteorites and some terrestrial samples by multiple-collector inductively coupled plasma mass spectrometry. Analyses of standard solutions produce Te stable isotope data with a long-term reproducibility (2SD) of 0.064‰ for δ130/125Te. Carbonaceous and enstatite chondrites display a range in δ130/125Te of 0.9‰ (0.2‰ amu-1) in their Te stable isotope signature, whereas ordinary chondrites present larger Te stable isotope fractionation, in particular for unequilibrated ordinary chondrites, with an overall variation of 6.3‰ for δ130/125Te (1.3‰ amu-1). Tellurium stable isotope variations in ordinary chondrites display no correlation with Te contents or metamorphic grade. The large Te stable isotope fractionation in ordinary chondrites is likely caused by evaporation and condensation processes during metamorphism in the meteorite parent bodies, as has been suggested for other moderately and highly volatile elements displaying similar isotope fractionation. Alternatively, they might represent a nebular signature or could have been produced during chondrule formation. Enstatite chondrites display slightly more negative δ130/125Te compared to carbonaceous chondrites and equilibrated ordinary chondrites. Small differences in the Te stable isotope composition are also present within carbonaceous chondrites and increase in the order CV-CO-CM-CI. These Te isotope variations within carbonaceous chondrites may be due to mixing of components that have distinct Te isotope signatures reflecting Te stable isotope fractionation in the early solar system or on the parent bodies and potentially small so-far unresolvable nucleosynthetic isotope anomalies of up to 0.27‰. The Te stable isotope data of carbonaceous and enstatite chondrites displays a general correlation with the oxidation state and hence might provide a record of the nebular formation environment. The Te stable isotope fractionation of the carbonaceous chondrites CI and CM (and CO potentially) overlap within uncertainty with data for terrestrial Te standard solutions, sediments and ore samples. Assuming the silicate Earth displays similar Te isotope fractionation as the studied terrestrial samples, the data indicate that the late veneer might have been delivered by material similar to CI or CM (or possibly) CO carbonaceous chondrites in terms of Te isotope composition. Nine terrestrial samples display resolvable Te stable isotope fractionation of 0.85 and 0.60‰ for δ130/125Te for sediment and USGS geochemical exploration reference samples, respectively. Tellurium isotopes therefore have the potential to become a new geochemical sedimentary proxy, as well as a proxy for ore-exploration.

Production and Engineering Methods for CARB-TEX (Trade Name) Batteries in Fork Lift Trucks

DTIC Science & Technology

1974-12-01

Temperature Batteries Tellurium Tetra Chloride Battery Pilot Line TO ABSTRACT (Contfinue on reverse side !I mvc.esy mid Identify by block number) This...chloride -1- as the electrolyte, and a tellurium tetrachloride additive. The porous carbon cathode is an aggregation of active carbon particles which have...energy storage using the Helmholtz double-layer princi- ple. However, after treating the carbon with the tellurium tetrachloride additve, the carbon

Thermodynamics of post-growth annealing of cadmium zinc telluride nuclear radiation detectors

NASA Astrophysics Data System (ADS)

Adams, Aaron Lee

Nuclear Radiation Detectors are used for detecting, tracking, and identifying radioactive materials which emit high-energy gamma and X-rays. The use of Cadmium Zinc Telluride (CdZnTe) detectors is particularly attractive because of the detector's ability to operate at room temperature and measure the energy spectra of gamma-ray sources with a high resolution, typically less than 1% at 662 keV. While CdZnTe detectors are acceptable imperfections in the crystals limit their full market potential. One of the major imperfections are Tellurium inclusions generated during the crystal growth process by the retrograde solubility of Tellurium and Tellurium-rich melt trapped at the growth interface. Tellurium inclusions trap charge carriers generated by gamma and X-ray photons and thus reduce the portion of generated charge carriers that reach the electrodes for collection and conversion into a readable signal which is representative of the ionizing radiation's energy and intensity. One approach in resolving this problem is post-growth annealing which has the potential of removing the Tellurium inclusions and associated impurities. The goal of this project is to use experimental techniques to study the thermodynamics of Tellurium inclusion migration in post-growth annealing of CdZnTe nuclear detectors with the temperature gradient zone migration (TGZM) technique. Systematic experiments will be carried out to provide adequate thermodynamic data that will inform the engineering community of the optimum annealing parameters. Additionally, multivariable correlations that involve the Tellurium diffusion coefficient, annealing parameters, and CdZnTe properties will be analyzed. The experimental approach will involve systematic annealing experiments (in Cd vapor overpressure) on different sizes of CdZnTe crystals at varying temperature gradients ranging from 0 to 60°C/mm (used to migrate the Tellurium inclusion to one side of the crystal), and at annealing temperatures ranging from 500 to 800°C. The characterization techniques that will be used to quantify the effects of the post-growth annealing experiments include: 1) 3D infrared transmission microscopy to measure the size, distribution, and concentration of Tellurium inclusions; 2) current-voltage measurements to determine the effect of post-growth annealing on the resistivity of CdZnTe crystals; and 3) X-ray diffraction topography, available at the National Synchrotron Light Source (NSLS) facilities at Brookhaven National Laboratory (BNL), to measure the correlation between device performance and annealing conditions

Low Power, Room Temperature Systems for the Detection and Identification of Radionuclides from Atmospheric Nuclear Test

DTIC Science & Technology

2013-07-01

3 2.0 TELLURIUM ANTISITES IN CdZnTe ...........................................................................•. 4 3.0 EFFECTS OF...five journals, reported in eleven presentations, and printed in four conference proceedings. 3 2.0 TELLURIUM ANTISITES IN CdZnTe 1. M. Ch~ S...Terterian, D. Ting, R.B. James, J.C. Erickson, R W. Yao, T.T. Lam. M. Szawlowski, and R. Sczeboitz, " Tellurium Antisites in CdZnTe," SPIE Proceedings

Targets for producing high purity I-123

NASA Technical Reports Server (NTRS)

Blue, J. W. (Inventor)

1978-01-01

Tellurium powder in improved targets is bombarded with a cyclotron beam to produce Xe-123. Flowing gas streams carry the Xe-123 through one cold trap which removes Xe-123 that subsequently decays to I-123. During this bombardment energy is deposited in the target material causing its temperature to rise. Some of the tellurium vaporizes and subsequently condenses on surfaces that are cooler than the vaporization temperature. Provision is made for the repeated bombardment of this condensed tellurium.

Association of tellurium resistance and bacteriophage inhibition conferred by R plasmids.

PubMed Central

Taylor, D E; Summers, A O

1979-01-01

Concomitant resistance to tellurium compounds (Ter) and inhibition of coli-phage development (Phi) are properties mediated by many H2 incompatibility group R plasmids which have been isolated from diverse bacterial and geographic sources. Ter plasmids from tellurium-resistant bacteria that were isolated from sewage and industrial wastes also mediated phage inhibition. Of these Ter plasmids, three from Citrobacter freundii belonged to the H incompatibility group, whereas three from Klebsiella pneumoniae did not. Images PMID:374351

Volatilization and precipitation of tellurium by aerobic, tellurite-resistant marine microbes.

PubMed

Ollivier, Patrick R L; Bahrou, Andrew S; Marcus, Sarah; Cox, Talisha; Church, Thomas M; Hanson, Thomas E

2008-12-01

Microbial resistance to tellurite, an oxyanion of tellurium, is widespread in the biosphere, but the geochemical significance of this trait is poorly understood. As some tellurite resistance markers appear to mediate the formation of volatile tellurides, the potential contribution of tellurite-resistant microbial strains to trace element volatilization in salt marsh sediments was evaluated. Microbial strains were isolated aerobically on the basis of tellurite resistance and subsequently examined for their capacity to volatilize tellurium in pure cultures. The tellurite-resistant strains recovered were either yeasts related to marine isolates of Rhodotorula spp. or gram-positive bacteria related to marine strains within the family Bacillaceae based on rRNA gene sequence comparisons. Most strains produced volatile tellurides, primarily dimethyltelluride, though there was a wide range of the types and amounts of species produced. For example, the Rhodotorula spp. produced the greatest quantities and highest diversity of volatile tellurium compounds. All strains also produced methylated sulfur compounds, primarily dimethyldisulfide. Intracellular tellurium precipitates were a major product of tellurite metabolism in all strains tested, with nearly complete recovery of the tellurite initially provided to cultures as a precipitate. Different strains appeared to produce different shapes and sizes of tellurium containing nanostructures. These studies suggest that aerobic marine yeast and Bacillus spp. may play a greater role in trace element biogeochemistry than has been previously assumed, though additional work is needed to further define and quantify their specific contributions.

X-Ray Diffraction Studies on Metal Deposition in Group D Streptococci

PubMed Central

Tucker, Fayne L.; Thomas, John W.; Appleman, Milo D.; Goodman, Stewart H.; Donohue, Jerry

1966-01-01

Tucker, Fayne L. (University of Southern California, Los Angeles), John W. Thomas, Milo D. Appleman, Stewart H. Goodman, and Jerry Donohue. X-ray diffraction studies on metal deposition in group D streptococci. J. Bacteriol. 92:1311–1314. 1966.—Streptococcus faecalis N83 and S. faecium K6A reduced several compounds of Group VI elements to the elemental form, but reduced none of several compounds tested containing elements of other groups. The elemental tellurium deposited by S. faecium K6A was in general of a larger particle size than that deposited by S. faecalis N83 as judged from X-ray diffraction analysis. The particle size of the deposited tellurium was correlated with the blackness of the precipitate produced by cells growing in the presence of tellurite. A black and gray variation was observed in S. faecium K6A which was considered to be due to particle size, the amount of tellurium present, and the location of the deposited tellurium. The gray color of S. faecium K6A was not due to the presence of any oxidized tellurium products. PMID:4958879

Synthesis of novel E-2-chlorovinyltellurium compounds based on the stereospecific anti-addition of tellurium tetrachloride to acetylene.

PubMed

Musalova, Maria V; Potapov, Vladimir A; Amosova, Svetlana V

2012-05-15

The reaction of tellurium tetrachloride with acetylene proceeds in a stereospecific anti-addition manner to afford the novel products E-2-chlorovinyltellurium trichloride and E,E-bis(2-chlorovinyl)tellurium dichloride. Reaction conditions for the selective preparation of each of these products were found. The latter was obtained in 90% yield in CHCl(3) under a pressure of acetylene of 10-15 atm, whereas the former product was formed in up to 72% yield in CCl(4) under a pressure of acetylene of 1-3 atm. Synthesis of the previously unknown E,E-bis(2-chlorovinyl) telluride, E,E-bis(2-chlorovinyl) ditelluride, E-2-chlorovinyl 1,2,2-trichloroethyl telluride and E,E-bis(2-chlorovinyl)-tellurium dibromide is described.

Inclusion free cadmium zinc tellurium and cadmium tellurium crystals and associated growth method

DOEpatents

Bolotnikov, Aleskey E [South Setauket, NY; James, Ralph B [Ridge, NY

2010-07-20

The present disclosure provides systems and methods for crystal growth of cadmium zinc tellurium (CZT) and cadmium tellurium (CdTe) crystals with an inverted growth reactor chamber. The inverted growth reactor chamber enables growth of single, large, high purity CZT and CdTe crystals that can be used, for example, in X-ray and gamma detection, substrates for infrared detectors, or the like. The inverted growth reactor chamber enables reductions in the presence of Te inclusions, which are recognized as an important limiting factor in using CZT or CdTe as radiation detectors. The inverted growth reactor chamber can be utilized with existing crystal growth techniques such as the Bridgman crystal growth mechanism and the like. In an exemplary embodiment, the inverted growth reactor chamber is a U-shaped ampoule.

COMPLETE REDUCTION OF TELLURITE TO PURE TELLURIUM METAL BY MICROORGANISMS

PubMed Central

Tucker, Fayne L.; Walper, John F.; Appleman, Milo Don; Donohue, Jerry

1962-01-01

Tucker, Fayne L. (University of Southern California, Los Angeles), John F. Walper, Milo Don Appleman, and Jerry Donohue. Complete reduction of tellurite to pure tellurium metal by microorganisms. J. Bacteriol. 83:1313–1314. 1962—The black precipitate produced in the presence of potassium tellurite by growing cells of Streptococcus faecalis N83 and Corynebacterium diphtheriae was shown, by X-ray diffraction analysis, to consist of metallic tellurium. The metal was not complexed, to any significant degree, with any organic material. PMID:13922991

Intergranular tellurium cracking of nickel-based alloys in molten Li, Be, Th, U/F salt mixture

NASA Astrophysics Data System (ADS)

Ignatiev, Victor; Surenkov, Alexander; Gnidoy, Ivan; Kulakov, Alexander; Uglov, Vadim; Vasiliev, Alexander; Presniakov, Mikhail

2013-09-01

In Russia, R&D on Molten Salt Reactor (MSR) are concentrated now on fast/intermediate spectrum concepts which were recognized as long term alternative to solid fueled fast reactors due to their attractive features: strong negative feedback coefficients, easy in-service inspection, and simplified fuel cycle. For high-temperature MSR corrosion of the metallic container alloy in primary circuit is the primary concern. Key problem receiving current attention include surface fissures in Ni-based alloys probably arising from fission product tellurium attack. This paper summarizes results of corrosion tests conducted recently to study effect of oxidation state in selected fuel salt on tellurium attack and to develop means of controlling tellurium cracking in the special Ni-based alloys recently developed for molten salt actinide recycler and tranforming (MOSART) system. Tellurium corrosion of Ni-based alloys was tested at temperatures up to 750 °C in stressed and unloaded conditions in molten LiF-BeF2 salt mixture fueled by about 20 mol% of ThF4 and 2 mol% of UF4 at different [U(IV)]/[U(III)] ratios: 0.7, 4, 20, 100 and 500. Following Ni-based alloys (in mass%): HN80М-VI (Mo—12, Cr—7.6, Nb—1.5), HN80МТY (Mo—13, Cr—6.8, Al—1.1, Ti—0.9), HN80МТW (Mo—9.4, Cr—7.0, Ti—1.7, W—5.5) and ЕМ-721 (W—25.2, Cr—5.7, Ti—0.17) were used for the study in the corrosion facility. If the redox state the fuel salt is characterized by uranium ratio [U(IV)]/[U(III)] < 1 the alloys' specimens get a more negative stationary electrode potential than equilibrium electrode potentials of some uranium intermetallic compounds and alloys with nickel and molybdenum. This leads to spontaneous behavior of alloy formation processes on the specimens' surface and further diffusion of uranium deep into the metallic phase. As consequence of this films of intermetallic compounds and alloys of nickel, molybdenum, tungsten with uranium are formed on the alloys specimens' surface, and intergranular corrosion does not take place. In the fuel salt with [U(IV)]/[U(III)] = 4-20 the potentials of uranium alloy formation with the main components of the tested alloys are not reached, that's why alloys and intermetallic compounds are not formed on the surface of the investigated chromium-nickel alloys. Under such conditions any intergranular tellurium corrosion of the selected alloys does not occur. In the fuel salt with [U(IV)/]/[U(III)] = 100 the potentials of uranium alloy formation with the main components of the tested alloys are not also reached. Under such redox conditions any traces intergranular tellurium IGC on the HN80MTY and H80M-VI alloys specimens are not found. Certain signs of incipient IGC in the form of tellurium presence on the grain boundaries in the HN80MTB and EM-721 alloys surface layer and formation of not too deep cracks on HN80MTB alloy surface were revealed at [U(IV)/]/[U(III)] = 100. With this uranium ratio in the presence of corrosion products on the surface of all of the alloys films, containing tellurium, metals of the construction alloys and carbon, are formed. In the melt with [U(IV)]/[U(III)] = 500 in all of the alloys tested the tellurium IGC took place. The HN80MTY alloy shows the maximum resistance to tellurium IGC. The intensity of tellurium IGC of the alloy (the K parameter) is by 3-5 times lower as compared to other alloys. The EM-721 alloy has the minimal resistance to tellurium IGC (K = 9200 pc m/cm, the depth of cracks is up to 434 μm). The studies have shown, that the intensity of the nickel alloys IGC is controlled by the [U(IV)]/[U(III)] ratio, and its dependence on this parameter is of threshold character. Providing the uranium ratio value's monitoring and regulation, it is possible to control the tellurium corrosion and in such a way to eliminate IGC completely or to minimize its value. The alloys strength characteristics and their structure were changed insignificantly after testing within the [U(IV)]/[U(III)] range from 0.7 tо 100. The changes are not linked with the influence of fuel salt, containing tellurium additions, but are stipulated by alloys structure, temperature factor, exposure time and mechanical loads. Significant effect of tellurium cracking on the alloys (excepting HN80MTY) strength characteristics was established after corrosion testing with [U(IV)]/[U(III)] = 500. In the absence of IGC all of the alloys investigated have a good ductility at high strength characteristics. The disrupture of specimens under mechanical tests both before and after corrosion tests of all alloys except for ЕМ-721 proceeds on a ductile mechanism. On the EM-721 alloy specimens, both in their initial state and after corrosion testing, clear signs of brittle destruction, caused by heterogeneity of its structure due to the presence of tungsten phase, are very clearly observed. The presence of such phases increases the alloy IGC and leads to reduction of the alloy resistance tellurium damage. The HN80MTY alloy has the best corrosion and mechanical properties. It does not undergo tellurium IGC in the molten 75LiF-5BeF2-20ThF4 salt mixture fueled by about 2 mol% of UF4 with [U(IV)]/[U(III)] ratio ⩽ 100. The alloy has high resistance to tellurium cracking at [U(IV)]/[U(III)] = 500. The alloy can be recommended as the main construction material for the fuel circuit with selected salt composition up to temperature 750 °С.

A glimpse on biological activities of tellurium compounds.

PubMed

Cunha, Rodrigo L O R; Gouvea, Iuri E; Juliano, Luiz

2009-09-01

Tellurium is a rare element which has been regarded as a toxic, non-essential trace element and its biological role is not clearly established to date. Besides of that, the biological effects of elemental tellurium and some of its inorganic and organic derivatives have been studied, leading to a set of interesting and promising applications. As an example, it can be highlighted the uses of alkali-metal tellurites and tellurates in microbiology, the antioxidant effects of organotellurides and diorganoditellurides and the immunomodulatory effects of the non-toxic inorganic tellurane, named AS-101, and the plethora of its uses. Inasmuch, the nascent applications of organic telluranes (organotelluranes) as protease inhibitors and its applications in disease models are the most recent contribution to the scenario of the biological effects and applications of tellurium and its compounds discussed in this manuscript.

Simultaneous quantitative analysis of arsenic, bismuth, selenium, and tellurium in soil samples using multi-channel hydride-generation atomic fluorescence spectrometry.

PubMed

Wang, Fang; Zhang, Gai

2011-03-01

The basic principles and the application of hydride-generation multi-channel atomic fluorescence spectrometry (HG-MC-AFS) in soil analysis are described. It is generally understood that only one or two elements can be simultaneously detected by commonly used one- or two-channel HG-AFS. In this work, a new sample-sensitive and effective method for the analysis of arsenic, bismuth, tellurium, and selenium in soil samples by simultaneous detection using HG-MC-AFS was developed. The method detection limits for arsenic, bismuth, tellurium, and selenium are 0.19 μg/g, 0.10 μg/g, 0.11 μg/g, and 0.08 μg/g, respectively. This method was successfully applied to the simultaneous determination of arsenic, bismuth, tellurium, and selenium in soil samples.

Enhancement of Au-Ag-Te contents in tellurium-bearing ore minerals via bioleaching

NASA Astrophysics Data System (ADS)

Choi, Nag-Choul; Cho, Kang Hee; Kim, Bong Ju; Lee, Soonjae; Park, Cheon Young

2018-03-01

The purpose of this study was to enhance the content of valuable metals, such as Au, Ag, and Te, in tellurium-bearing minerals via bioleaching. The ore samples composed of invisible Au and Au paragenesis minerals (such as pyrite, chalcopyrite, sphalerite and galena) in combination with tellurium-bearing minerals (hessite, sylvanite and Tellurobismuthite) were studied. Indigenous microbes from mine drainage were isolated and identified as Acidithiobacillus ferrooxidans, which were used in bioleaching after adaption to copper. The effect of the microbial adaption on the bioleaching performance was then compared with the results produced by the non-adaptive process. The microbial adaption enhanced the Au-Ag-Te contents in biological leaching of tellurium-bearing ore minerals. This suggests that bioleaching with adapted microbes can be used both as a pretreatment and in the main recovery processes of valuable metals.

Volatilization and Precipitation of Tellurium by Aerobic, Tellurite-Resistant Marine Microbes▿ †

PubMed Central

Ollivier, Patrick R. L.; Bahrou, Andrew S.; Marcus, Sarah; Cox, Talisha; Church, Thomas M.; Hanson, Thomas E.

2008-01-01

Microbial resistance to tellurite, an oxyanion of tellurium, is widespread in the biosphere, but the geochemical significance of this trait is poorly understood. As some tellurite resistance markers appear to mediate the formation of volatile tellurides, the potential contribution of tellurite-resistant microbial strains to trace element volatilization in salt marsh sediments was evaluated. Microbial strains were isolated aerobically on the basis of tellurite resistance and subsequently examined for their capacity to volatilize tellurium in pure cultures. The tellurite-resistant strains recovered were either yeasts related to marine isolates of Rhodotorula spp. or gram-positive bacteria related to marine strains within the family Bacillaceae based on rRNA gene sequence comparisons. Most strains produced volatile tellurides, primarily dimethyltelluride, though there was a wide range of the types and amounts of species produced. For example, the Rhodotorula spp. produced the greatest quantities and highest diversity of volatile tellurium compounds. All strains also produced methylated sulfur compounds, primarily dimethyldisulfide. Intracellular tellurium precipitates were a major product of tellurite metabolism in all strains tested, with nearly complete recovery of the tellurite initially provided to cultures as a precipitate. Different strains appeared to produce different shapes and sizes of tellurium containing nanostructures. These studies suggest that aerobic marine yeast and Bacillus spp. may play a greater role in trace element biogeochemistry than has been previously assumed, though additional work is needed to further define and quantify their specific contributions. PMID:18849455

Novel Electronically Conducting Tellurium Oxides

NASA Astrophysics Data System (ADS)

Subramanian, Mas; Siritanon, Theerunan; Sleight, Arthur

2010-03-01

Tellurium oxides seldom show measurable electronic conductivity. Tellurium oxides that appear to have Te^5+ contain Te^4+ and Te^6+ in two distinct crystallographic sites and are electronic insulators. Here we report on the synthesis and characterization of several new tellurium rich oxides of the general formula, CsMxTe2-xO6, crystallizing in modified pyrochlore structure. Most of the compounds reported here are black in color with some exhibiting good electronic conductivities (2 S/cm) and Seebeck measurements indicate all are n-type. The observation of high electronic conductivities in compounds like CsGe0.5Te1.5O6, CsAl0.33Te1.67O6 confirms that observed conductivity is arising from doping of electrons into the empty 5s orbitals of Te^6+. This reduction is apparently accompanied with some small deviation from the ideal formula: oxygen content and/or ratio of cations on octahedral sites. This is in consistent with single-crystal X-ray as well as powder neutron diffraction structure refinements and the observed sign of the Seebeck coefficient. To our knowledge, this is a first observance of high electrical conductivity in mixed valent tellurium oxides.

Tellurium Stable Isotope Fractionation in Chondritic Meteorites

NASA Astrophysics Data System (ADS)

Fehr, M. A.; Hammond, S. J.; Parkinson, I. J.

2014-09-01

New Te double spike procedures were set up to obtain high-precision accurate Te stable isotope data. Tellurium stable isotope data for 16 chondrite falls are presented, providing evidence for significant Te stable isotope fractionation.

Occupational absorption of tellurium: a report of two cases.

PubMed Central

Blackadder, E S; Manderson, W G

1975-01-01

Industrial uses of tellurium are limited, and reported cases of tellurium absorption of occupational origin are rare. Two such cases are reported here. Both showed typical signs and symptoms of intoxication; in particular, the stench of sour garlic was noted on breath and from excreta. An unusual feature was the bluish-black discoloration of the webs of the fingers and streaks on the face and neck. Full hospital investigation was negative. No permanent damage resulted and each patient made a spontaneous recovery without treatment. Images PMID:123755

Relation of the Yield of the Isomeric Pair Te$sup 121$m, Te$sup 121$, Formed in the Nuclear Reaction, Sb$sup 121$(d,2n)Te$sup 121$. Report No. 61; RELACION DE LOS RENDIMENTOS DEL PAR ISOMERICO Te$sup 121$m, Te$sup 121$, FORMADO EN LA REACCION NUCLEAR Sb$sup 121$(d,2N)Te$sup 121$. INFORME NO. 61

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

Nassiff, S.J.; Abecasis, S.; Mocoroa, A.

1961-01-01

The effective cross sections of the isomeric pair, tellurium-121m- tellurium-121 in the reaction antimony121(d,2n)tellurium-121 were determined experimentally for deuteron energies from 9 to 28 Mev. (tr-auth)

Tellurium nano-structure based NO gas sensor.

PubMed

Kumar, Vivek; Sen, Shashwati; Sharma, M; Muthe, K P; Jagannath; Gaur, N K; Gupta, S K

2009-09-01

Tellurium nanotubes were grown on bare and silver/gold nanoparticle (nucleation centers) deposited silicon substrates by vacuum deposition technique at a substrate temperature of 100 degrees C under high vacuum conditions. Silver and gold nanoparticles prepared on (111) oriented silicon substrates were found to act as nucleation centers for growth of Tellurium nanostructures. Density of nanotubes was found to increase while their diameter reduced when grown using metallic nanoparticle template. These Te nanostructures were investigated for their gas sensitivity. Tellurium nanotubes on Ag templates showed better response to NO in comparison to H2S and NH3 gases. Selectivity in response to NO was improved in comparison to Te thin film sensors reported earlier. The gas sensing mechanism was investigated using Raman and X-ray photoelectron spectroscopy techniques. The interaction of NO is seen to yield increased adsorption of oxygen that in turn increases hole density and conductivity in the material.

Solvent extraction of tellurium from chloride solutions using tri-n-butyl phosphate: conditions and thermodynamic data.

PubMed

Li, Dongchan; Guo, Yafei; Deng, Tianlong; Chen, Yu-Wei; Belzile, Nelson

2014-01-01

The extractive separation of tellurium (IV) from hydrochloric acid media with tri-n-butyl phosphate (TBP) in kerosene was investigated. The dependence on the extraction of tellurium species, concentrations of tellurium and TBP, extraction time and stage, organic/aqueous ratio, and interferences from coexist metallic ions were examined and are discussed. Besides, the stripping agent and stripping time were also studied. It was found that the extraction reaction corresponds to the neutral complex formation mechanism and the extracted species is TeCl4 · 3TBP and that the extraction process is exothermic. The thermodynamic parameters of enthalpy (ΔH), entropy (ΔS), and free energy (ΔG) of the extraction process were evaluated at -26.2 kJ · mol(-1), -65.6 J · mol(-1) · K(-1), and -7.0 kJ · mol(-1), respectively at 293 K.

Solvent Extraction of Tellurium from Chloride Solutions Using Tri-n-butyl Phosphate: Conditions and Thermodynamic Data

PubMed Central

Li, Dongchan; Guo, Yafei; Deng, Tianlong; Chen, Yu-Wei

2014-01-01

The extractive separation of tellurium (IV) from hydrochloric acid media with tri-n-butyl phosphate (TBP) in kerosene was investigated. The dependence on the extraction of tellurium species, concentrations of tellurium and TBP, extraction time and stage, organic/aqueous ratio, and interferences from coexist metallic ions were examined and are discussed. Besides, the stripping agent and stripping time were also studied. It was found that the extraction reaction corresponds to the neutral complex formation mechanism and the extracted species is TeCl4 ·3TBP and that the extraction process is exothermic. The thermodynamic parameters of enthalpy (ΔH), entropy (ΔS), and free energy (ΔG) of the extraction process were evaluated at −26.2 kJ·mol−1, −65.6 J·mol−1 ·K−1, and −7.0 kJ·mol−1, respectively at 293 K. PMID:24757422

Tellurium: an element with great biological potency and potential.

PubMed

Ba, Lalla Aicha; Döring, Mandy; Jamier, Vincent; Jacob, Claus

2010-10-07

Tellurium has long appeared as a nearly 'forgotten' element in Biology, with most studies focusing on tellurite, tellurate and a handful of organic tellurides. During the last decade, several discoveries have fuelled a renewed interest in this element. Bioincorporation of telluromethionine provides a new approach to add heavy atoms to selected sites in proteins. Cadmium telluride (CdTe) nanoparticles are fluorescent and may be used as quantum dots in imaging and diagnosis. The antibiotic properties of tellurite, long known yet almost forgotten, have attracted renewed interest, especially since the biochemical mechanisms of tellurium cytotoxicity are beginning to emerge. The close chemical relationship between tellurium and sulfur also transcends into in vitro and in vivo situations and provides new impetus for the development of enzyme inhibitors and redox modulators, some of which may be of interest in the field of antibiotics and anticancer drug design.

Tellurium n-type doping of highly mismatched amorphous GaN 1-xAs x alloys in plasma-assisted molecular beam epitaxy

DOE PAGES

Novikov, S. V.; Ting, M.; Yu, K. M.; ...

2014-10-01

In this paper we report our study on n-type Te doping of amorphous GaN 1-xAs x layers grown by plasma-assisted molecular beam epitaxy. We have used a low temperature PbTe source as a source of tellurium. Reproducible and uniform tellurium incorporation in amorphous GaN 1-xAs x layers has been successfully achieved with a maximum Te concentration of 9×10²⁰ cm⁻³. Tellurium incorporation resulted in n-doping of GaN 1-xAs x layers with Hall carrier concentrations up to 3×10¹⁹ cm⁻³ and mobilities of ~1 cm²/V s. The optimal growth temperature window for efficient Te doping of the amorphous GaN 1-xAs x layers hasmore » been determined.« less

Purification of telluric acid for SNO+ neutrinoless double-beta decay search

NASA Astrophysics Data System (ADS)

Hans, S.; Rosero, R.; Hu, L.; Chkvorets, O.; Chan, W. T.; Guan, S.; Beriguete, W.; Wright, A.; Ford, R.; Chen, M. C.; Biller, S.; Yeh, M.

2015-09-01

Tellurium-130 has the highest natural abundance of any double-beta decay isotopes. Recently it has been developed as a promising candidate for loading in liquid scintillator to explore the Majorana or Dirac nature of the neutrino through a search for neutrinoless double beta decay (0νββ). To this end, procedures have been developed to transfer tellurium ions into the organic liquid by a water-based loading technology. However, traces of naturally occurring radioactivity and cosmic-ray induced isotopes introduced into the scintillator with tellurium could produce undesirable contaminations in the 130Te 0νββ region. Measurements using various elemental spikes prepared from different chemical forms indicate that the uses of self-scavenging as well as acid and thermal recrystallization prior to the preparation of a tellurium-loaded liquid scintillator can deplete U and Th and several cosmic-activated isotopes from Te feedstock by a factor of 102-103 in a single pass. The process is also found to improve the optical transmission in the blue region, sensible to the photomultiplier tube, by removing traces of colored impurities. In addition to the scintillator-based experiments, this cleansing scheme has potential applications to the production of radiopure tellurium crystals for other rare-event experiments.

Speciation of inorganic tellurium from seawater by ICP-MS following magnetic SPE separation and preconcentration.

PubMed

Huang, Chaozhang; Hu, Bin

2008-03-01

A new method was developed for the speciation of inorganic tellurium species in seawater by inductively coupled plasma-MS (ICP-MS) following selective magnetic SPE (MSPE) separation. Within the pH range of 2-9, tellurite (Te(IV)) could be quantitatively adsorbed on gamma-mercaptopropyltrimethoxysilane (gamma-MPTMS) modified silica-coated magnetic nanoparticles (MNPs), while the tellurate (Te(VI)) was not retained and remained in solution. Without filtration or centrifugation, these tellurite-loaded MNPs could be separated easily from the aqueous solution by simply applying external magnetic field. The Te(IV) adsorbed on the MNPs could be recovered quantitatively using a solution containing 2 mol/L HCl and 0.03 mol/L K2Cr2O7. Te(VI) was reduced to Te(IV) by L-cysteine prior to the determination of total tellurium, and its assay was based on subtracting Te(IV) from total tellurium. The parameters affecting the separation were investigated systematically and the optimal separation conditions were established. Under the optimal conditions, the LOD obtained for Te(IV) was 0.079 ng/L, while the precision was 7.0% (C = 10 ng/L, n = 7). The proposed method was successfully applied to the speciation of inorganic tellurium in seawater.

Dismantling and chemical characterization of spent Peltier thermoelectric devices for antimony, bismuth and tellurium recovery.

PubMed

Balva, Maxime; Legeai, Sophie; Garoux, Laetitia; Leclerc, Nathalie; Meux, Eric

2017-04-01

Major uses of thermoelectricity concern refrigeration purposes, using Peltier devices, mainly composed of antimony, bismuth and tellurium. Antimony was identified as a critical raw material by EU and resources of bismuth and tellurium are not inexhaustible, so it is necessary to imagine the recycling of thermoelectric devices. That for, a complete characterization is needed, which is the aim of this work. Peltier devices were manually dismantled in three parts: the thermoelectric legs, the alumina plates on which remain the electrical contacts and the silicone paste used to connect the plates. The characterization was performed using five Peltier devices. It includes mass balances of the components, X-ray diffraction analysis of the thermoelectric legs and elemental analysis of each part of the device. It appears that alumina represents 45% of a Peltier device in weight. The electrical contacts are mainly composed of copper and tin, and the thermoelectric legs of bismuth, tellurium and antimony. Thermoelectric legs appear to be Se-doped Bi 2 Te 3 and (Bi 0,5 Sb 1,5 )Te 3 for n type and p type semiconductors, respectively. This work shows that Peltier devices can be considered as a copper ore and that thermoelectric legs contain high amounts of bismuth, tellurium and antimony compared to their traditional resources.

First example of a high-level correlated calculation of the indirect spin-spin coupling constants involving tellurium: tellurophene and divinyl telluride.

PubMed

Rusakov, Yury Yu; Krivdin, Leonid B; Østerstrøm, Freja F; Sauer, Stephan P A; Potapov, Vladimir A; Amosova, Svetlana V

2013-08-21

This paper documents the very first example of a high-level correlated calculation of spin-spin coupling constants involving tellurium taking into account relativistic effects, vibrational corrections and solvent effects for medium sized organotellurium molecules. The (125)Te-(1)H spin-spin coupling constants of tellurophene and divinyl telluride were calculated at the SOPPA and DFT levels, in good agreement with experimental data. A new full-electron basis set, av3z-J, for tellurium derived from the "relativistic" Dyall's basis set, dyall.av3z, and specifically optimized for the correlated calculations of spin-spin coupling constants involving tellurium was developed. The SOPPA method shows a much better performance compared to DFT, if relativistic effects calculated within the ZORA scheme are taken into account. Vibrational and solvent corrections are next to negligible, while conformational averaging is of prime importance in the calculation of (125)Te-(1)H spin-spin couplings. Based on the performed calculations at the SOPPA(CCSD) level, a marked stereospecificity of geminal and vicinal (125)Te-(1)H spin-spin coupling constants originating in the orientational lone pair effect of tellurium has been established, which opens a new guideline in organotellurium stereochemistry.

Tellurium notebooks-An environment for reproducible dynamical modeling in systems biology.

PubMed

Medley, J Kyle; Choi, Kiri; König, Matthias; Smith, Lucian; Gu, Stanley; Hellerstein, Joseph; Sealfon, Stuart C; Sauro, Herbert M

2018-06-01

The considerable difficulty encountered in reproducing the results of published dynamical models limits validation, exploration and reuse of this increasingly large biomedical research resource. To address this problem, we have developed Tellurium Notebook, a software system for model authoring, simulation, and teaching that facilitates building reproducible dynamical models and reusing models by 1) providing a notebook environment which allows models, Python code, and narrative to be intermixed, 2) supporting the COMBINE archive format during model development for capturing model information in an exchangeable format and 3) enabling users to easily simulate and edit public COMBINE-compliant models from public repositories to facilitate studying model dynamics, variants and test cases. Tellurium Notebook, a Python-based Jupyter-like environment, is designed to seamlessly inter-operate with these community standards by automating conversion between COMBINE standards formulations and corresponding in-line, human-readable representations. Thus, Tellurium brings to systems biology the strategy used by other literate notebook systems such as Mathematica. These capabilities allow users to edit every aspect of the standards-compliant models and simulations, run the simulations in-line, and re-export to standard formats. We provide several use cases illustrating the advantages of our approach and how it allows development and reuse of models without requiring technical knowledge of standards. Adoption of Tellurium should accelerate model development, reproducibility and reuse.

Purification and in vitro antioxidant activities of tellurium-containing phycobiliproteins from tellurium-enriched Spirulina platensis.

PubMed

Yang, Fang; Wong, Ka-Hing; Yang, Yufeng; Li, Xiaoling; Jiang, Jie; Zheng, Wenjie; Wu, Hualian; Chen, Tianfeng

2014-01-01

Tellurium-containing phycocyanin (Te-PC) and allophycocyanin (Te-APC), two organic tellurium (Te) species, were purified from tellurium-enriched Spirulina platensis by a fast protein liquid chromatographic method. It was found that the incorporation of Te into the peptides enhanced the antioxidant activities of both phycobiliproteins. With fractionation by ammonium sulfate precipitation and hydroxylapatite chromatography, Te-PC and Te-APC could be effectively separated with high purity, and Te concentrations were 611.1 and 625.3 μg g(-1) protein in Te-PC and Te-APC, respectively. The subunits in the proteins were identified by using MALDI-TOF-TOF mass spectrometry. Te incorporation enhanced the antioxidant activities of both phycobiliproteins, as examined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid assay. Moreover, Te-PC and Te-APC showed dose-dependent protection on erythrocytes against the water-soluble free radical initiator 2,2'-azo(2-asmidinopropane)dihydrochloride-induced hemolysis. In the hepatoprotective model, apoptotic cell death and nuclear condensation induced by tert-butyl hydroperoxide in HepG2 cells was significantly attenuated by Te-PC and Te-APC. Taken together, these results suggest that Te-PC and Te-APC are promising Te-containing proteins with application potential for treatment of diseases related to oxidative stress.

Purification and in vitro antioxidant activities of tellurium-containing phycobiliproteins from tellurium-enriched Spirulina platensis

PubMed Central

Yang, Fang; Wong, Ka-Hing; Yang, Yufeng; Li, Xiaoling; Jiang, Jie; Zheng, Wenjie; Wu, Hualian; Chen, Tianfeng

2014-01-01

Tellurium-containing phycocyanin (Te-PC) and allophycocyanin (Te-APC), two organic tellurium (Te) species, were purified from tellurium-enriched Spirulina platensis by a fast protein liquid chromatographic method. It was found that the incorporation of Te into the peptides enhanced the antioxidant activities of both phycobiliproteins. With fractionation by ammonium sulfate precipitation and hydroxylapatite chromatography, Te-PC and Te-APC could be effectively separated with high purity, and Te concentrations were 611.1 and 625.3 μg g−1 protein in Te-PC and Te-APC, respectively. The subunits in the proteins were identified by using MALDI-TOF-TOF mass spectrometry. Te incorporation enhanced the antioxidant activities of both phycobiliproteins, as examined by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid assay. Moreover, Te-PC and Te-APC showed dose-dependent protection on erythrocytes against the water-soluble free radical initiator 2,2′-azo(2-asmidinopropane)dihydrochloride-induced hemolysis. In the hepatoprotective model, apoptotic cell death and nuclear condensation induced by tert-butyl hydroperoxide in HepG2 cells was significantly attenuated by Te-PC and Te-APC. Taken together, these results suggest that Te-PC and Te-APC are promising Te-containing proteins with application potential for treatment of diseases related to oxidative stress. PMID:25336922

The enhancing of Au-Ag-Te content in tellurium-bearing ore mineral by bio-oxidation-leaching

NASA Astrophysics Data System (ADS)

Kim, PyeongMan; Kim, HyunSoo; Myung, EunJi; Kim, YoonJung; Lee, YongBum; Park*, CheonYoung

2015-04-01

The purpose of this study is to enhance the content of valuable metals such as Au-Ag-Te in tellurium-bearing minerals by bio-oxidation-leaching. It was confirmed that pyrite, chalcopyrite, sphalerite and galena were produced together with tellurium-bearing minerals including hessite, sylvanite and tellurobismuthite from ore minerals and concentrates through microscopic observation and SEM/EDS analysis. In a bio-oxidation-leaching experiment, with regard to Au, Ag, Te, Cu and Fe, the changes in the amount of leaching and the content of leaching residues were compared and analyzed with each other depending on the adaptation of an indigenous microbe identified as Acidithiobacillus ferrooxidans. As a result of the experiment, the Au-Ag-Te content in tellurium-bearing ore mineral was enhanced in the order of physical oxidation leaching, physical/non-adaptive bio-oxidation-leaching and physical/adaptive biological leaching. It suggests that the bio-oxidation-leaching using microbes adapted in tellurium-bearing ore mineral can be used as a pre-treatment and a main process in a recovery process of valuable metals. "This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(NRF-2013R1A1A2004898)"

SEPARATION OF RADIOACTIVE COLUMBIUM TRACER

DOEpatents

Glendenin, L.E.; Gest, H.

1958-08-26

A process is presented for the recovery of radioactive columbium from solutions containing such columbium together with radioactive tellurium. The columbium and tellurium values are separated from such solutions by means of an inorganic oxide carrier precipitate, such as MnO/sub 2/. This oxide carrier precipitate and its associated columbium and telluriuan values are then dissolved in an aqueous acidic solution and nonradioactive tellurium, in an ionic form, is then introduced into such solution, for example in the form of H/sub 2/TeO/sub 3/. The tellurium present in the solution is then reduced to the elemental state and precipitates, and is then separated from the supernataat solution. A basic acetate precipitate is formed in the supernatant and carries the remaining columblum values therefrom. After separation, this basic ferric acetate precipitate is dissolved, and the ferric ions are removed by means of an organic solvent extraction process utilizing ether. The remaining solution contains carrier-free columbium as its only metal ion.

Glutathione Reductase-Mediated Synthesis of Tellurium-Containing Nanostructures Exhibiting Antibacterial Properties

PubMed Central

Pugin, Benoit; Cornejo, Fabián A.; Muñoz-Díaz, Pablo; Muñoz-Villagrán, Claudia M.; Vargas-Pérez, Joaquín I.; Arenas, Felipe A.

2014-01-01

Tellurium, a metalloid belonging to group 16 of the periodic table, displays very interesting physical and chemical properties and lately has attracted significant attention for its use in nanotechnology. In this context, the use of microorganisms for synthesizing nanostructures emerges as an eco-friendly and exciting approach compared to their chemical synthesis. To generate Te-containing nanostructures, bacteria enzymatically reduce tellurite to elemental tellurium. In this work, using a classic biochemical approach, we looked for a novel tellurite reductase from the Antarctic bacterium Pseudomonas sp. strain BNF22 and used it to generate tellurium-containing nanostructures. A new tellurite reductase was identified as glutathione reductase, which was subsequently overproduced in Escherichia coli. The characterization of this enzyme showed that it is an NADPH-dependent tellurite reductase, with optimum reducing activity at 30°C and pH 9.0. Finally, the enzyme was able to generate Te-containing nanostructures, about 68 nm in size, which exhibit interesting antibacterial properties against E. coli, with no apparent cytotoxicity against eukaryotic cells. PMID:25193000

Stable Te isotope fractionation in tellurium-bearing minerals from precious metal hydrothermal ore deposits

NASA Astrophysics Data System (ADS)

Fornadel, Andrew P.; Spry, Paul G.; Haghnegahdar, Mojhgan A.; Schauble, Edwin A.; Jackson, Simon E.; Mills, Stuart J.

2017-04-01

The tellurium isotope compositions of naturally-occurring tellurides, native tellurium, and tellurites were measured by multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) and compared to theoretical values for equilibrium mass-dependent isotopic fractionation of representative Te-bearing species estimated with first-principles thermodynamic calculations. Calculated fractionation models suggest that 130/125Te fractionations as large as 4‰ occur at 100 °C between coexisting tellurates (Te VI) and tellurides (Te -II) or or native tellurium Te(0), and smaller, typically <1‰, fractionations occur between coexisting Te(-I) or Te(-II) (Au,Ag)Te2 minerals (i.e., calaverite, krennerite) and (Au,Ag)2Te minerals (i.e., petzite, hessite). In general, heavyTe/lightTe is predicted to be higher for more oxidized species, and lower for reduced species. Tellurides in the system Au-Ag-Te and native tellurium analyzed in this study have values of δ130/125Te = -1.54‰ to 0.44‰ and δ130/125Te = -0.74‰ to 0.16‰, respectively, whereas those for tellurites (tellurite, paratellurite, emmonsite and poughite) range from δ130/125Te = -1.58‰ to 0.59‰. Thus, the isotopic composition for both oxidized and reduced species are broadly coincident. Calculations of per mil isotopic variation per amu for each sample suggest that mass-dependent processes are responsible for fractionation. In one sample of coexisting primary native tellurium and secondary emmonsite, δ130/125Te compositions were identical. The coincidence of δ130/125Te between all oxidized and reduced species in this study and the apparent lack of isotopic fractionation between native tellurium and emmonsite in one sample suggest that oxidation processes cause little to no fractionation. Because Te is predominantly transported as an oxidized aqueous phase or as a reduced vapor phase under hydrothermal conditions, either a reduction of oxidized Te in hydrothermal liquids or deposition of Te from a reduced vapor to a solid is necessary to form the common tellurides and native tellurium in ore-forming systems. Our data suggest that these sorts of reactions during mineralization may account for a ∼3‰ range of δ130/125Te values. Based on the data ranges for Te minerals from various ore deposits, the underpinning geologic processes responsible for mineralization seem to have primary control on the magnitude of fractionation, with tellurides in epithermal gold deposits showing a narrower range of isotope values than those in orogenic gold and volcanogenic massive sulfide deposits.

Detection of the Second r-process Peak Element Tellurium in Metal-poor Stars

NASA Astrophysics Data System (ADS)

Roederer, Ian U.; Lawler, James E.; Cowan, John J.; Beers, Timothy C.; Frebel, Anna; Ivans, Inese I.; Schatz, Hendrik; Sobeck, Jennifer S.; Sneden, Christopher

2012-03-01

Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, we detect neutral tellurium in three metal-poor stars enriched by products of r-process nucleosynthesis, BD +17 3248, HD 108317, and HD 128279. Tellurium (Te, Z = 52) is found at the second r-process peak (A ≈ 130) associated with the N = 82 neutron shell closure, and it has not been detected previously in Galactic halo stars. The derived tellurium abundances match the scaled solar system r-process distribution within the uncertainties, confirming the predicted second peak r-process residuals. These results suggest that tellurium is predominantly produced in the main component of the r-process, along with the rare earth elements. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs GO-8342 and GO-12268. Some of the data presented in this Letter were obtained from the Multimission Archive at the Space Telescope Science Institute (MAST). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. These data are associated with programs GO-7348, GO-7402, GO-8197, and GO-9455.

Mineral resource of the month: tellurium

USGS Publications Warehouse

George, Micheal W.

2006-01-01

Global demand for tellurium has grown significantly in recent years owing to increased use in solar cells in the United States and Europe, thermoelectronics (especially in China) and steelmaking worldwide. Estimated global production, however, has remained relatively unchanged over the same period, while accumulated inventories have been exhausted, leading to a supply shortfall.

Thick tellurium target preparation by vacuum deposition

NASA Astrophysics Data System (ADS)

Stolarz, Anna

1999-12-01

Tellurium targets of thickness up to 6.5 mg/cm 2 on carbon backings were prepared by vacuum deposition. The influence of the crucible dimension, treatment of the backing foil by glow discharge and substrate cooling on the Te sticking efficiency was studied in order to achieve the best yield.

Ultra-sensitive ROS-responsive tellurium-containing polymers.

PubMed

Cao, Wei; Gu, Yuwei; Li, Tianyu; Xu, Huaping

2015-04-25

A novel tellurium-containing polymer micelle system is reported to be responsive to 100 μM H2O2 and can undergo a series of morphological changes. The polymer micelles also respond to 2 Gy gamma radiation, which is the exact dosage a patient receives per day for clinical radiation therapy.

Coordination responsive tellurium-containing multilayer film for controlled delivery.

PubMed

Cao, Wei; Wang, Lu; Xu, Huaping

2015-03-28

A coordination-responsive tellurium containing film was fabricated for controlled release. The coordination chemistry between telluride molecules and cisplatin was utilized for the loading of cisplatin, while competitive ligands were used for triggered release. This work could enrich the coordination responsive system and further tune the release kinetics of cisplatin.

Magnetic resonance force microscopy quantum computer with tellurium donors in silicon.

PubMed

Berman, G P; Doolen, G D; Hammel, P C; Tsifrinovich, V I

2001-03-26

We propose a magnetic resonance force microscopy (MRFM)-based nuclear spin quantum computer using tellurium impurities in silicon. This approach to quantum computing combines well-developed silicon technology and expected advances in MRFM. Our proposal does not use electrostatic gates to realize quantum logic operations.

Electron Transport in Tellurium Nanowires

NASA Astrophysics Data System (ADS)

Berezovets, V. A.; Kumzerov, Yu. A.; Firsov, Yu. A.

2018-02-01

The temperature and magnetic field dependences of the voltage-current characteristics of tellurium nanowires manufactured via the insertion of tellurium into chrysotile asbestos pores from a melt have been measured. The measurements have been performed within a broad range of temperatures and magnetic fields. The results of such measurements are analyzed by means of their comparison with the predictions of theoretical models developed for the case of one-dimensional structures. The obtained dependences are concluded to most closely correspond to Luttinger liquid theory predictions. This result agrees with the concepts that the major mechanism of current in such one-dimensional wires does not depend on the material inserted into pores, but depends only on the dimension of conducting wires.

Dimethylselenide and Dimethyltelluride Formation by a Strain of Penicillium

PubMed Central

Fleming, R. W.; Alexander, M.

1972-01-01

A strain of Penicillium which produced dimethylselenide from inorganic selenium compounds was isolated from raw sewage. Sulfate and methionine enhanced growth of the fungus and its production of dimethylselenide in media containing selenite. In solutions containing selenate, methionine inhibited dimethylselenide formation while stimulating proliferation of the fungus. Dimethylselenide was also generated from inorganic selenide. Alkylation did not appear to be a significant mechanism of selenium detoxication by this organism. Dimethyltelluride was also produced by the organism from several tellurium compounds, but this product was synthesized only in the presence of both tellurium and selenium. The yields of dimethylselenide and dimethyltelluride varied with the relative concentrations of selenium and tellurium in the medium. PMID:5079352

Pancharatnam-Berry phase and kinetic magnetoelectric effect in trigonal tellurium

NASA Astrophysics Data System (ADS)

Şahin, C.; Rou, J.; Ma, J.; Pesin, D. A.

2018-05-01

We study the kinetic magnetoelectric effect (current-induced magnetization including both the orbital and spin contributions) in three-dimensional conductors, specializing to the case of p -doped trigonal tellurium. We include both intrinsic and extrinsic contributions to the effect, which stem from the band structure of the crystal, and from disorder scattering, respectively. Specifically, we determine the dependence of the kinetic magnetoelectric response on the hole doping in tellurium, and show that the intrinsic and extrinsic effects dominate for low and high levels of doping, respectively. The results of this work imply that three-dimensional helical metals are promising for spintronics applications, in particular, they can provide robust control over current-induced magnetic torques.

Branched tellurium hollow nanofibers by galvanic displacement reaction and their sensing performance toward nitrogen dioxide.

PubMed

Park, Hosik; Jung, Hyunsung; Zhang, Miluo; Chang, Chong Hyun; Ndifor-Angwafor, N George; Choa, Yongho; Myung, Nosang V

2013-04-07

Electrospinning and galvanic displacement reaction were combined to synthesize ultra-long hollow tellurium (Te) nanofibers with controlled dimensions, morphology and crystallinity by simply tailoring the electrolyte concentration applied. Within different morphologies of nanofibers, the branched Te nanostructure shows the greatest sensing performance towards NO2 at room temperature.

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

Charkin, Dmitri O.; Black, Cameron; Downie, Lewis J.

Two new rare-earth – alkali – tellurium oxide halides were synthesized by a salt flux technique and characterized by single-crystal X-ray diffraction. The structures of the new compounds Cs{sub 7}Sm{sub 11}[TeO{sub 3}]{sub 12}Cl{sub 16} (I) and Rb{sub 7}Nd{sub 11}[TeO{sub 3}]{sub 12}Br{sub 16} (II) (both tetragonal, space group I4/mcm) correspond to the sequence of [MLn{sub 11}(TeO{sub 3}){sub 12}] and [M{sub 6}X{sub 16}] layers and bear very strong similarities to those of known selenite analogs. We discuss the trends in similarities and differences in compositions and structural details between the Se and Te compounds; more members of the family are predicted. -more » Graphical abstract: Two new rare-earth – alkali – tellurium oxide halides were predicted and synthesized. - Highlights: • Two new rare-earth – alkali – tellurium oxide halides were synthesized. • They adopt slab structure of rare earth-tellurium-oxygen and CsCl-like slabs. • The Br-based CsCl-like slabs have been observed first in this layered family.« less

Glutathione reductase-mediated synthesis of tellurium-containing nanostructures exhibiting antibacterial properties.

PubMed

Pugin, Benoit; Cornejo, Fabián A; Muñoz-Díaz, Pablo; Muñoz-Villagrán, Claudia M; Vargas-Pérez, Joaquín I; Arenas, Felipe A; Vásquez, Claudio C

2014-11-01

Tellurium, a metalloid belonging to group 16 of the periodic table, displays very interesting physical and chemical properties and lately has attracted significant attention for its use in nanotechnology. In this context, the use of microorganisms for synthesizing nanostructures emerges as an eco-friendly and exciting approach compared to their chemical synthesis. To generate Te-containing nanostructures, bacteria enzymatically reduce tellurite to elemental tellurium. In this work, using a classic biochemical approach, we looked for a novel tellurite reductase from the Antarctic bacterium Pseudomonas sp. strain BNF22 and used it to generate tellurium-containing nanostructures. A new tellurite reductase was identified as glutathione reductase, which was subsequently overproduced in Escherichia coli. The characterization of this enzyme showed that it is an NADPH-dependent tellurite reductase, with optimum reducing activity at 30°C and pH 9.0. Finally, the enzyme was able to generate Te-containing nanostructures, about 68 nm in size, which exhibit interesting antibacterial properties against E. coli, with no apparent cytotoxicity against eukaryotic cells. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Sulfur, selenium and tellurium pseudopeptides: synthesis and biological evaluation.

PubMed

Shaaban, Saad; Sasse, Florenz; Burkholz, Torsten; Jacob, Claus

2014-07-15

A new series of sulfur, selenium and tellurium peptidomimetic compounds was prepared employing the Passerini and Ugi isocyanide based multicomponent reactions (IMCRs). These reactions were clearly superior to conventional methods traditionally used for organoselenium and organotellurium synthesis, such as classical nucleophilic substitution and coupling methods. From the biological point of view, these compounds are of considerable interest because of suspected anticancer and antimicrobial activities. While the sulfur and selenium containing compounds generally did not show either anticancer or antimicrobial activities, their tellurium based counterparts frequently exhibited antimicrobial activity and were also cytotoxic. Some of the compounds synthesized even showed selective activity against certain cancer cells in cell culture. These compounds induced a cell cycle delay in the G0/G1 phase. At closer inspection, the ER and the actin cytoskeleton appeared to be the primary cellular targets of these tellurium compounds, in line with some of our previous studies. As most of these peptidomimetic compounds also comply with Lipinski's Rule of Five, they promise good bioavailability, which needs to be studied as part of future investigations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tellurium Mobility Through Mine Environments

NASA Astrophysics Data System (ADS)

Dorsk, M.

2015-12-01

Tellurium is a rare metalloid that has received minimal research regarding environmental mobility. Observations of Tellurium mobility are mainly based on observations of related metalloids such as selenium and beryllium; yet little research has been done on specific Tellurium behavior. This laboratory work established the environmental controls that influence Tellurium mobility and chemical speciation in aqueous driven systems. Theoretical simulations show possible mobility of Te as Te(OH)3[+] at highly oxidizing and acidic conditions. Movement as TeO3[2-] under more basic conditions may also be possible in elevated Eh conditions. Mobility in reducing environments is theoretically not as likely. For a practical approach to investigate mobility conditions for Te, a site with known Tellurium content was chosen in Colorado. Composite samples were selected from the top, center and bottom of a tailings pile for elution experiments. These samples were disintegrated using a rock crusher and pulverized with an automated mortar and pestle. The material was then classified to 70 microns. A 10g sample split was digested in concentrated HNO3 and HF and analyzed by Atomic Absorption Spectroscopy to determine initial Te concentrations. Additional 10g splits from each location were subjected to elution in 100 mL of each of the following solutions; nitric acid to a pH of 1.0, sulfuric acid to a pH of 2.0, sodium hydroxide to a pH of 12, ammonium hydroxide to a pH of 10, a pine needle/soil tea from material within the vicinity of the collection site to a pH of 3.5 and lastly distilled water to serve as control with a pH of 7. Sulfuric acid was purposefully chosen to simulate acid mine drainage from the decomposition of pyrite within the mine tailings. Sample sub sets were also inundated with 10mL of a 3% hydrogen peroxide solution to induce oxidizing conditions. All collected eluates were then analyzed by atomic absorption spectroscopy (AAS) to measure Tellurium concentrations in each sample. The results provide a comparison of possible environmental Te mobility factors. While the process of bioavailability is not specifically addressed, preliminary data indicate a reference to perhaps assess impact to the local community and livestock relying on the San Miguel River, which is effected by run-off from the mine site.

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

Novikov, S. V.; Ting, M.; Yu, K. M.

In this paper we report our study on n-type Te doping of amorphous GaN 1-xAs x layers grown by plasma-assisted molecular beam epitaxy. We have used a low temperature PbTe source as a source of tellurium. Reproducible and uniform tellurium incorporation in amorphous GaN 1-xAs x layers has been successfully achieved with a maximum Te concentration of 9×10²⁰ cm⁻³. Tellurium incorporation resulted in n-doping of GaN 1-xAs x layers with Hall carrier concentrations up to 3×10¹⁹ cm⁻³ and mobilities of ~1 cm²/V s. The optimal growth temperature window for efficient Te doping of the amorphous GaN 1-xAs x layers hasmore » been determined.« less

Microbial processing of tellurium as a tool in biotechnology.

PubMed

Turner, Raymond J; Borghese, Roberto; Zannoni, Davide

2012-01-01

Here, we overview the most recent advances in understanding the bacterial mechanisms that stay behind the reduction of tellurium oxyanions in both planktonic cells and biofilms. This is a topic of interest for basic and applied research because microorganisms are deeply involved in the transformation of metals and metalloids in the environment. In particular, the recent observation that toxic tellurite can be precipitated either inside or outside the cells being used as electron sink to support bacterial growth, opens new perspectives for both microbial physiologists and biotechnologists. As promising nanomaterials, tellurium based nanoparticles show unique electronic and optical properties due to quantum confinement effects to be used in the area of chemistry, electronics, medicine and environmental biotechnologies. Copyright © 2011 Elsevier Inc. All rights reserved.

Biology and toxicology of tellurium explored by speciation analysis.

PubMed

Ogra, Yasumitsu

2017-05-24

Tellurium (Te) is widely used in industry because it has unique physicochemical properties. Although Te is a non-essential element in animals and plants, it is expected to be metabolized to organometallic compounds having a carbon-Te bond in living organisms exposed to inorganic Te compounds. Thus, the speciation and identification of tellurometabolites are expected to contribute to the depiction of the metabolic chart of Te. Speciation by elemental mass spectrometry and identification by molecular mass spectrometry coupled with separation techniques have significantly contributed to the discovery of tellurometabolites in animals and plants. The aim of this mini review is to present recent advances in the biology and toxicology of tellurium as revealed by speciation and identification by molecular mass spectrometry.

Ligand-Substitution Reactions of the Tellurium Compound AS-101 in Physiological Aqueous and Alcoholic Solutions.

PubMed

Silberman, Alon; Albeck, Michael; Sredni, Benjamin; Albeck, Amnon

2016-11-07

Since its first crystallization, the aqueous structure of the tellurium-containing experimental drug AS-101 has never been studied. We show that, under the aqueous conditions in which it is administered, AS-101 is subjected to an immediate ligand-substitution reaction with water, yielding a stable hydrolyzed oxide anion product that is identified, for the first time, to be TeOCl 3 - . Studying the structure of AS-101 in propylene glycol (PG), an alcoholic solvent often used for the topical and oral administration of AS-101, revealed the same phenomenon of ligand-substitution reaction between the alcoholic ligands. Upon exposure to water, the PG-substituted product is also hydrolyzed to the same tellurium(IV) oxide form, TeOCl 3 - .

Synthesis and antimicrobial activity of gold/silver-tellurium nanostructures.

PubMed

Chang, Hsiang-Yu; Cang, Jinshun; Roy, Prathik; Chang, Huan-Tsung; Huang, Yi-Cheng; Huang, Chih-Ching

2014-06-11

Gold-tellurium nanostructures (Au-Te NSs), silver-tellurium nanostructures (Ag-Te NSs), and gold/silver-tellurium nanostructures (Au/Ag-Te NSs) have been prepared through galvanic reactions of tellurium nanotubes (Te NTs) with Au(3+), Ag(+), and both ions, respectively. Unlike the use of less environmentally friendly hydrazine, fructose as a reducing agent has been used to prepare Te NTs from TeO2 powders under alkaline conditions. The Au/Ag-Te NSs have highly catlaytic activity to convert nonfluorescent Amplex Red to form fluorescent product, revealing their great strength of generating reactive oxygen species (ROS). Au/Ag-Te NSs relative to the other two NSs exhibit greater antimicrobial activity toward the growth of E. coli, S. enteritidis, and S. aureus; the minimal inhibitory concentration (MIC) values of Au/Ag-Te NSs were much lower (>10-fold) than that of Ag-Te NSs and Au-Te NSs. The antibacterial activity of Au/Ag-Te NSs is mainly due to the release of Ag(+) ions and Te-related ions and also may be due to the generated ROS which destroys the bacteria membrane. In vitro cytotoxicity and hemolysis analyses have revealed their low toxicity in selected human cell lines and insignificant hemolysis in red blood cells. In addition, inhibition zone measurements using a Au/Ag-Te NSs-loaded konjac jelly film have suggested that it has great potential in practial application such as wound dressing for reducing bacterial wound infection. Having great antibacterial activitiy and excellent biocompatibility, the low-cost Au/Ag-Te NSs hold great potential as effective antimicrobial drugs.

Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction

USGS Publications Warehouse

Hubert, A.E.; Chao, T.T.

1985-01-01

A rock, soil, or stream-sediment sample is decomposed with hydrofluoric acid, aqua regia, and hydrobromic acid-bromine solution. Gold, thallium, indium and tellurium are separated and concentrated from the sample digest by a two-step MIBK extraction at two concentrations of hydrobromic add. Gold and thallium are first extracted from 0.1M hydrobromic acid medium, then indium and tellurium are extracted from 3M hydrobromic acid in the presence of ascorbic acid to eliminate iron interference. The elements are then determined by flame atomic-absorption spectrophotometry. The two-step solvent extraction can also be used in conjunction with electrothermal atomic-absorption methods to lower the detection limits for all four metals in geological materials. ?? 1985.

Biological accumulation of tellurium nanorod structures via reduction of tellurite by Shewanella oneidensis MR-1.

PubMed

Kim, Dong-Hun; Kanaly, Robert A; Hur, Hor-Gil

2012-12-01

The dissimilatory metal-reducing bacterium, Shewanella oneidensis MR-1, reduced tellurite (Te(IV), TeO(3)(2-)) to elemental tellurium under anaerobic conditions resulting in the intracellular accumulation of needle shaped crystalline Te(0) nanorods. Fatty acid analyses showed that toxic Te(IV) increased the unsaturated fatty acid composition of the lipid components of the cell membrane, implying a deconstruction of the integrity of the cellular membrane structure. The current results suggest that dissimilatory metal reducing bacteria such as S. oneidensis MR-1 may play an important role in recycling toxic tellurium elements, and may be applied as a novel selective biological filter via the accumulation of industry-applicable rare materials, Te(0) nanorods, in the cell. Copyright © 2012 Elsevier Ltd. All rights reserved.

Analysis of the accelerated crucible rotation technique applied to the gradient freeze growth of cadmium zinc telluride

NASA Astrophysics Data System (ADS)

Divecha, Mia S.; Derby, Jeffrey J.

2017-06-01

We employ finite-element modeling to assess the effects of the accelerated crucible rotation technique (ACRT) on cadmium zinc telluride (CZT) crystals grown from a gradient freeze system. Via consideration of tellurium segregation and transport, we show, for the first time, that steady growth from a tellurium-rich melt produces persistent undercooling in front of the growth interface, likely leading to morphological instability. The application of ACRT rearranges melt flows and tellurium transport but, in contrast to conventional wisdom, does not altogether eliminate undercooling of the melt. Rather, a much more complicated picture arises, where spatio-temporal realignment of undercooled melt may act to locally suppress instability. A better understanding of these mechanisms and quantification of their overall effects will allow for future growth optimization.

Acousto-optical and SAW propagation characteristics of temperature stable multilayered structures based on LiNbO3 and diamond

NASA Astrophysics Data System (ADS)

Shandilya, Swati; Sreenivas, K.; Gupta, Vinay

2008-01-01

Theoretical studies on the surface acoustic wave (SAW) properties of c-axis oriented LiNbO3/IDT/diamond and diamond/IDT/128° rotated Y-X cut LiNbO3 multilayered structures have been considered. Both layered structures exhibit a positive temperature coefficient of delay (TCD) characteristic, and a zero TCD device is obtained after integrating with an over-layer of either tellurium dioxide (TeO2) or silicon dioxide (SiO2). The presence of a TeO2 over-layer enhanced the electromechanical coupling coefficients of both multilayered structures, which acts as a better temperature compensation layer than SiO2. The temperature stable TeO2/LiNbO3/IDT/diamond layered structure exhibits good electromechanical coefficient and higher phase velocity for SAW device applications. On the other hand, a high acousto-optical (AO) figure of merit (30-37) × 10-15 s3 kg-1 has been obtained for the temperature stable SiO2/diamond/IDT/LiNbO3 layered structure indicating a promising device structure for AO applications.

Compositions of doped, co-doped and tri-doped semiconductor materials

DOEpatents

Lynn, Kelvin [Pullman, WA; Jones, Kelly [Colfax, WA; Ciampi, Guido [Watertown, MA

2011-12-06

Semiconductor materials suitable for being used in radiation detectors are disclosed. A particular example of the semiconductor materials includes tellurium, cadmium, and zinc. Tellurium is in molar excess of cadmium and zinc. The example also includes aluminum having a concentration of about 10 to about 20,000 atomic parts per billion and erbium having a concentration of at least 10,000 atomic parts per billion.

Versatile telluracycle synthesis via the sequential electrophilic telluration of C(sp2)–Zn and C(sp2)–H bonds† †Electronic supplementary information (ESI) available. CCDC 1523262–1523264. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc01162h Click here for additional data file. Click here for additional data file.

PubMed Central

Wu, Bin; Melvina; Wu, Xiangyang; Lee Yeow, Edwin Kok

2017-01-01

We report herein a new approach for the synthesis of tellurium-bridged aromatic compounds based on the sequential electrophilic telluration of C(sp2)–Zn and C(sp2)–H bonds with tellurium(iv) chlorides. A combination of transition metal-catalyzed (migratory) arylmetalation of alkynes and sequential telluration allows for the expedient construction of a library of functionalized benzo[b]tellurophenes. Furthermore, a variety of heteroarene-fused benzotellurophenes and other novel tellurium-embedded polycyclic aromatics can be readily synthesized from the corresponding 2-iodoheterobiaryls. PMID:28970880

Recovery of 131I from alkaline solution of n-irradiated tellurium target using a tiny Dowex-1 column.

PubMed

Chattopadhyay, Sankha; Saha Das, Sujata

2010-10-01

A simple and inexpensive ion-exchange chromatography method for the separation of medically useful no-carrier-added (nca) iodine radionuclides from bulk amounts of irradiated tellurium dioxide (TeO(2)) target was developed and tested using (131)I. The radiochemical separation was performed using a very small Dowex-1x8 ion-exchange column. The overall radiochemical yield for the complete separation of (131)I was 92+/-1.8 (standard deviation) % (n=8). The separated nca (131)I was of high, approximately 99%, radionuclidic and radiochemical purity and did not contain detectable amounts of the target material. This method may be adopted for the radiochemical separation of other different iodine radionuclides produced from tellurium matrices through cyclotron as well as reactor irradiation. Copyright 2010 Elsevier Ltd. All rights reserved.

Luminescent and thermochromic properties of tellurium(IV) halide complexes with cesium

NASA Astrophysics Data System (ADS)

Sedakova, T. V.; Mirochnik, A. G.

2016-02-01

The spectral-luminescent and thermochromic properties of complex compounds of the composition Cs2TeHal6 (Hal = Cl, Br, I) are studied. The interrelation between the geometric structure and spectral-luminescent properties is studied using the example on complex compounds of tellurium(IV) halides with cesium. The Stokes shift and the luminescence intensity of Te(IV) ions with island octahedral coordination are found to depend on the position of the A band in the luminescence excitation spectra, the diffuse reflection, and the energy of the luminescent 3 P 1 → 1 S 0 transition of the tellurium(IV) ion. The maximum luminescence intensity and the minimum Stokes shift at 77 and 300 K are observed for Cs2TeCl6. The geometrical and electronic factors responsible for luminescence intensification in Te(IV) complexes under study are analyzed.

U.S. Combat Commands’ Participation in the Proliferation Security Initiative: A Training Manual

DTIC Science & Technology

2009-01-01

cadmium-zinc- tellurium DHS Department of Homeland Security DoD Department of Defense EAA Export Administration Act EAR Export Administration Regulations EU...Pulsed fast neutron analysis PSI Proliferation Security Initiative Pu Plutonium SCO Shanghai Cooperation Organization SFI Security Freight Initiative...resolution) sodium iodide (NaI) and (intermediate-resolution) cadmium-zinc- tellurium (CZT) detectors may not have the energy resolution and/or sensitivity

Recovery of Elemental Tellurium Nanoparticles by the Reduction of Tellurium Oxyanions in a Methanogenic Microbial Consortium.

PubMed

Ramos-Ruiz, Adriana; Field, Jim A; Wilkening, Jean V; Sierra-Alvarez, Reyes

2016-02-02

This research focuses on the microbial recovery of elemental tellurium (Te(0)) from aqueous streams containing soluble tellurium oxyanions, tellurate (Te(VI)), and tellurite (Te(IV)). An anaerobic mixed microbial culture occurring in methanogenic granular sludge was able to biocatalyze the reduction of both Te oxyanions to produce Te(0) nanoparticles (NPs) in sulfur-free medium. Te(IV) reduction was seven times faster than that of Te(VI), such that Te(IV) did not accumulate to a great extent during Te(VI) reduction. Endogenous substrates in the granular sludge provided the electron equivalents required to reduce Te oxyanions; however, the reduction rates were modestly increased with an exogenous electron donor such as H2. The effect of four redox mediators (anthraquinone-2,6-disulfonate, hydroxocobalamin, riboflavin, and lawsone) was also tested. Riboflavin increased the rate of Te(IV) reduction eleven-fold and also enhanced the fraction Te recovered as extracellular Te(0) NPs from 21% to 64%. Lawsone increased the rate of Te(VI) reduction five-fold, and the fraction of Te recovered as extracellular material increased from 49% to 83%. The redox mediators and electron donors also impacted the morphologies and localization of Te(0) NPs, suggesting that NP production can be tailored for a particular application.

Sulfate Assimilation Mediates Tellurite Reduction and Toxicity in Saccharomyces cerevisiae▿†

PubMed Central

Ottosson, Lars-Göran; Logg, Katarina; Ibstedt, Sebastian; Sunnerhagen, Per; Käll, Mikael; Blomberg, Anders; Warringer, Jonas

2010-01-01

Despite a century of research and increasing environmental and human health concerns, the mechanistic basis of the toxicity of derivatives of the metalloid tellurium, Te, in particular the oxyanion tellurite, Te(IV), remains unsolved. Here, we provide an unbiased view of the mechanisms of tellurium metabolism in the yeast Saccharomyces cerevisiae by measuring deviations in Te-related traits of a complete collection of gene knockout mutants. Reduction of Te(IV) and intracellular accumulation as metallic tellurium strongly correlated with loss of cellular fitness, suggesting that Te(IV) reduction and toxicity are causally linked. The sulfate assimilation pathway upstream of Met17, in particular, the sulfite reductase and its cofactor siroheme, was shown to be central to tellurite toxicity and its reduction to elemental tellurium. Gene knockout mutants with altered Te(IV) tolerance also showed a similar deviation in tolerance to both selenite and, interestingly, selenomethionine, suggesting that the toxicity of these agents stems from a common mechanism. We also show that Te(IV) reduction and toxicity in yeast is partially mediated via a mitochondrial respiratory mechanism that does not encompass the generation of substantial oxidative stress. The results reported here represent a robust base from which to attack the mechanistic details of Te(IV) toxicity and reduction in a eukaryotic organism. PMID:20675578

Investigation of biomethylation of arsenic and tellurium during composting.

PubMed

Diaz-Bone, Roland A; Raabe, Maren; Awissus, Simone; Keuter, Bianca; Menzel, Bernd; Küppers, Klaus; Widmann, Renatus; Hirner, Alfred V

2011-05-30

Though the process of composting features a high microbiological activity, its potential to methylate metals and metalloids has been little investigated so far in spite of the high impact of this process on metal(loid) toxicity and mobility. Here, we studied the biotransformation of arsenic, tellurium, antimony, tin and germanium during composting. Time resolved investigation revealed a highly dynamic process during self-heated composting with markedly differing time patterns for arsenic and tellurium species. Extraordinary high concentrations of up to 150 mg kg(-1) methylated arsenic species as well as conversion rates up to 50% for arsenic and 5% for tellurium were observed. In contrast, little to no conversion was observed for antimony, tin and germanium. In addition to experiments with metal(loid) salts, composting of arsenic hyperaccumulating ferns Pteris vittata and P. cretica grown on As-amended soils was studied. Arsenic accumulated in the fronds was efficiently methylated resulting in up to 8 mg kg(-1) methylated arsenic species. Overall, these studies indicate that metal(loid)s can undergo intensive biomethylation during composting. Due to the high mobility of methylated species this process needs to be considered in organic waste treatment of metal(loid) contaminated waste materials. Copyright © 2010 Elsevier B.V. All rights reserved.

Facile One-Pot Synthesis of Tellurium Nanorods as Antioxidant and Anticancer Agents.

PubMed

Huang, Wei; Wu, Hualian; Li, Xiaoling; Chen, Tianfeng

2016-08-19

Nanorods have been utilized in targeted therapy, controlled release, molecular diagnosis, and molecule imaging owing to their large surface area and optical, magnetic, electronic, and structural properties. However, low stability and complex synthetic methods have substantially limited the application of tellurium nanorods for use as antioxidant and anticancer agents. Herein, a facile one-pot synthesis of functionalized tellurium nanorods (PTNRs) by using a hydrothermal synthetic system with a polysaccharide-protein complex (PTR), which was extracted from Pleurotus tuber-regium, as a capping agent is described. PTNRs remained stable in water and in phosphate-buffered saline and exhibited high hemocompatibility. Interestingly, these nanorods possessed strong antioxidant activity for scavenging 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS(.+) ) and 2,2-diphenyl-1-picrylhydrazylhydrate (DPPH) free radicals and demonstrated novel anticancer activities. However, these nanorods exhibited low cytotoxicity toward normal human cells. In addition, the PTNRs effectively induced a decrease in the mitochondrial membrane potential in a dose-dependent manner, which indicated that mitochondrial dysfunction might play an important role in PTNR-induced apoptosis. Therefore, this study provides a one-pot strategy for the facile synthesis of tellurium nanorods with novel antioxidant and anticancer application potentials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recovery of Elemental Tellurium Nanoparticles by the Reduction of Tellurium Oxyanions in a Methanogenic Microbial Consortium

PubMed Central

Ramos-Ruiz, Adriana; Field, Jim A.; Wilkening, Jean V.; Sierra-Alvarez, Reyes

2016-01-01

This research focuses on the microbial recovery of elemental tellurium (Te0) from aqueous streams containing soluble tellurium oxyanions, tellurate (TeVI) and tellurite (TeIV). An anaerobic mixed microbial culture occurring in methanogenic granular sludge was able to biocatalyze the reduction of both Te oxyanions to produce Te0 nanoparticles (NPs) in sulfur-free medium. TeIV reduction was 7-fold faster than that of TeVI, such that TeIV did not accumulate to a great extent during TeVI reduction. Endogenous substrates in the granular sludge provided the electron equivalents required to reduce Te oxyanions; however, the reduction rates were modestly increased with an exogenous electron donor such as H2. The effect of four redox mediators (anthraquinone-2,6-disulfonate, hydroxocobalamin, riboflavin, and lawsone) was also tested. Riboflavin increased the rate of TeIV reduction by 11-fold and also enhanced the fraction Te recovered as extracellular Te0 NPs from 21% to 64%. Lawsone increased the rate of TeVI reduction by 5-fold and the fraction of Te recovered as extracellular material increased from 49% to 83%. The redox mediators and electron donors also impacted the morphologies and localization of Te0 NPs, suggesting that NP production can be tailored for a particular application. PMID:26735010

Use of separate ZnTe interface layers to form ohmic contacts to p-CdTe films

DOEpatents

Gessert, T.A.

1999-06-01

A method of is disclosed improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurium-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact. 11 figs.

Terahertz and infrared transmission of an organic/inorganic hybrid thermoelectric material

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

Heyman, J. N., E-mail: heyman@macalester.edu; Alebachew, B. A.; Kaminski, Z. S.

2014-04-07

We report terahertz and infrared transmission measurements of a high-performance thermoelectric material containing tellurium nanowires in a conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) matrix. The DC electrical conductivity of the hybrid material (41 S/cm) is approximately one hundred times that of pure PEDOT:PSS and more than 400 times that of a film of pure tellurium nanowires, while the terahertz-frequency (THz) conductivity of PEDOT:PSS and the hybrid material are comparable at f ∼ 2THz. A frequency-dependent conductivity model indicates that the increased DC conductivity of the hybrid material results from an increase in the DC charge mobility rather than in the free charge density. We suggestmore » that the increased DC conductivity of the hybrid material results from an increase in linkage between PEDOT domains by the tellurium nanowires.« less

Ultrasensitive ROS-Responsive Coassemblies of Tellurium-Containing Molecules and Phospholipids.

PubMed

Wang, Lu; Fan, Fuqiang; Cao, Wei; Xu, Huaping

2015-07-29

Reactive oxygen species (ROS) play crucial roles in cell signaling and redox homeostasis and are strongly related to metabolic activities. The increase of the ROS concentration in organisms can result in several diseases, such as cardiovascular diseases and cancer. The concentration of ROS in biologically relevant conditions is typically as low as around tens of micromolars to 100 μM H2O2, which makes it necessary to develop ultrasensitive ROS-responsive systems. A general approach is reported here to fabricate an ultrasensitive ROS-responsive system via coassembly between tellurium-containing molecules and phospholipids, combining the ROS-responsiveness of tellurium and the biocompatibility of phospholipids. By using dynamic light scattering, transmission electron microscopy, scanning electron microscopy, and NMR spectra, coassembly behaviors and the responsiveness of the coassemblies have been investigated. These coassemblies can respond to 100 μM H2O2, which is a biologically relevant ROS concentration, and demonstrate reversible redox properties.

Enhancing Army S&T Lessons from Project Hindsight Revisited

DTIC Science & Technology

2007-01-01

Stinger–POST was equipped with a dual wave length detector assembly: one detector that operated at the mid- infrared and another detector that...as well reduce power and save space. • The Javelin CLU’s IR detectors require cooling to a very low temperature to increase the signal-to- noise ...The detectors are made of an alloy of cadmium-tellurium and mercury-tellurium (termed mercury cadmium telluride or HgCdTe ). Development of the 2D

Use of Iodine-131 to Tellurium-132 Ratios for Assessing the Relationships between Human Inhaled Radioactivity and Environmental Monitoring after the Accident in Fukushima.

PubMed

Uchiyama, Koji; Miyashita, Masami; Tanishima, Yoshinobu; Maeda, Shigenobu; Sato, Hitoshi; Yoshikawa, Jun; Watanabe, Shuji; Shibata, Masamichi; Ohhira, Shuji; Kobashi, Gen

2018-03-09

Significant differences in findings were seen between the intake amounts of iodine-131 that were derived from direct measurements and the estimated intake from environmental monitoring data at the Fukushima accident. To clarify these discrepancies, we have investigated the iodine-131 and tellurium-132 body burdens of five human subjects, who after being exposed to a radioactive plume, underwent 21.5 h whole body counter measurements at Fukui Prefectural Hospital, so clear intake scenario and thyroid counter measurement data were available. To determine the iodine-131 and tellurium-132 body burdens, we introduced a new method of whole body counter calibration composed of a self-consistent approach with the time-dependent correction efficiency factors concept. The ratios of iodine-131 to tellurium-132, ranging from 0.96 ± 0.05 to 2.29 ± 0.38, were consistent with results of the environmental measurements. The 24 h iodine uptake values ranging from 12.1-16.0% were within euthyroid range in Japanese people. These results suggest, even if the relatively low thyroid iodine uptake in the Japanese population was taken into consideration, that there is no doubt about the consistency between direct measurements and environmental monitoring data. Adequate intake scenario is suggested to be principally important to estimate the inhaled radioactivity in areas in or around nuclear accidents.

Pyridine-2,6-Bis(Thiocarboxylic Acid) Produced by Pseudomonas stutzeri KC Reduces and Precipitates Selenium and Tellurium Oxyanions

PubMed Central

Zawadzka, Anna M.; Crawford, Ronald L.; Paszczynski, Andrzej J.

2006-01-01

The siderophore of Pseudomonas stutzeri KC, pyridine-2,6-bis(thiocarboxylic acid) (pdtc), is shown to detoxify selenium and tellurium oxyanions in bacterial cultures. A mechanism for pdtc's detoxification of tellurite and selenite is proposed. The mechanism is based upon determination using mass spectrometry and energy-dispersive X-ray spectrometry of the chemical structures of compounds formed during initial reactions of tellurite and selenite with pdtc. Selenite and tellurite are reduced by pdtc or its hydrolysis product H2S, forming zero-valent pdtc selenides and pdtc tellurides that precipitate from solution. These insoluble compounds then hydrolyze, releasing nanometer-sized particles of elemental selenium or tellurium. Electron microscopy studies showed both extracellular precipitation and internal deposition of these metalloids by bacterial cells. The precipitates formed with synthetic pdtc were similar to those formed in pdtc-producing cultures of P. stutzeri KC. Culture filtrates of P. stutzeri KC containing pdtc were also active in removing selenite and precipitating elemental selenium and tellurium. The pdtc-producing wild-type strain KC conferred higher tolerance against selenite and tellurite toxicity than a pdtc-negative mutant strain, CTN1. These observations support the hypothesis that pdtc not only functions as a siderophore but also is involved in an initial line of defense against toxicity from various metals and metalloids. PMID:16672449

Hydrogen-assisted post-growth substitution of tellurium into molybdenum disulfide monolayers with tunable compositions

NASA Astrophysics Data System (ADS)

Yin, Guoli; Zhu, Dancheng; Lv, Danhui; Hashemi, Arsalan; Fei, Zhen; Lin, Fang; Krasheninnikov, Arkady V.; Zhang, Ze; Komsa, Hannu-Pekka; Jin, Chuanhong

2018-04-01

Herein we report the successful doping of tellurium (Te) into molybdenum disulfide (MoS2) monolayers to form MoS2x Te2(1-x) alloy with variable compositions via a hydrogen-assisted post-growth chemical vapor deposition process. It is confirmed that H2 plays an indispensable role in the Te substitution into as-grown MoS2 monolayers. Atomic-resolution transmission electron microscopy allows us to determine the lattice sites and the concentration of introduced Te atoms. At a relatively low concentration, tellurium is only substituted in the sulfur sublattice to form monolayer MoS2(1-x)Te2x alloy, while with increasing Te concentration (up to ˜27.6% achieved in this study), local regions with enriched tellurium, large structural distortions, and obvious sulfur deficiency are observed. Statistical analysis of the Te distribution indicates the random substitution. Density functional theory calculations are used to investigate the stability of the alloy structures and their electronic properties. Comparison with experimental results indicate that the samples are unstrained and the Te atoms are predominantly substituted in the top S sublattice. Importantly, such ultimately thin Janus structure of MoS2(1-x)Te2x exhibits properties that are distinct from their constituents. We believe our results will inspire further exploration of the versatile properties of asymmetric 2D TMD alloys.

Copper tellurium oxides - A playground for magnetism

NASA Astrophysics Data System (ADS)

Norman, M. R.

2018-04-01

A variety of copper tellurium oxide minerals are known, and many of them exhibit either unusual forms of magnetism, or potentially novel spin liquid behavior. Here, I review a number of the more interesting materials with a focus on their crystalline symmetry and, if known, the nature of their magnetism. Many of these exist (so far) in mineral form only, and most have yet to have their magnetic properties studied. This means a largely unexplored space of materials awaits our exploration.

Copper Tellurium Oxides - A Playground for Magnetism.

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

Norman, M. R.

A variety of copper tellurium oxide minerals are known, and many of them exhibit either unusual forms of magnetism, or potentially novel spin liquid behavior. Here, I review a number of the more interesting materials with a focus on their crystalline symmetry and, if known, the nature of their magnetism. Many of these exist (so far) in mineral form only, and most have yet to have their magnetic properties studied. This means a largely unexplored space of materials awaits our exploration.

Irreversible inhibition of human cathepsins B, L, S and K by hypervalent tellurium compounds.

PubMed

Cunha, Rodrigo L O R; Gouvêa, Iuri E; Feitosa, Geovana P V; Alves, Márcio F M; Brömme, Dieter; Comasseto, João V; Tersariol, Ivarne L S; Juliano, Luiz

2009-11-01

The inhibition of human cysteine cathepsins B, L, S and K was evaluated by a set of hypervalent tellurium compounds (telluranes) comprising both organic and inorganic derivatives. All telluranes studied showed a time- and concentration-dependent irreversible inhibition of the cathepsins, and their second-order inactivation rate constants were determined. The organic derivatives were potent inhibitors of the cathepsins and clear specificities were detected, which were parallel to their known substrate specificities. In all cases, the activity of the tellurane-inhibited cathepsins was recovered by treatment of the inactivated enzymes with reducing agents. The maximum stoichiometry of the reaction between cysteine residues and telluranes were also determined. The presented data indicate that it is possible to design organic compounds with a tellurium(IV) moiety as a novel warhead that covalently modifies the catalytic cysteine, and which also form strong interactions with subsites of cathepsins B, L, S and K, resulting in more specific inhibition.

A simple and rapid technique for radiochemical separation of iodine radionuclides from irradiated tellurium using an activated charcoal column.

PubMed

Chattopadhyay, Sankha; Saha Das, Sujata

2009-10-01

A simple and inexpensive method for the separation of medically useful no-carrier-added (nca) iodine radionuclides from bulk amounts of irradiated tellurium dioxide (TeO(2)) target was developed. The beta(-) emitting (131)I radionuclide, produced by the decay of (131)Te through the (nat)Te(n, gamma)(131)Te nuclear reaction, was used for standardization of the radiochemical separation procedure. The radiochemical separation was performed by precipitation followed by column (activated charcoal) chromatography. Quantitative post-irradiation recovery of the TeO(2) target material (98-99%), in a form suitable for reuse in future irradiations, was achieved. The overall radiochemical yield for the complete separation of (131)I was 75-85% (n=8). The separated nca (131)I was of high, approximately 99%, radionuclidic and radiochemical purities and did not contain detectable amounts of the target material. This method can be adopted for the radiochemical separation of other different iodine radionuclides produced from tellurium matrices through cyclotron as well as reactor irradiation.

The synthesis of ternary acetylides with tellurium: Li 2 TeC 2 and Na 2 TeC 2

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

Németh, Károly; Unni, Aditya K.; Kalnmals, Christopher

The synthesis of ternary acetylides Li 2TeC 2 and Na 2TeC 2 is presented as the first example of ternary acetylides with metalloid elements instead of transition metals. The synthesis was carried out by the direct reaction of the corresponding bialkali acetylides with tellurium powder in liquid ammonia. Alternatively, the synthesis of Na 2TeC 2 was also carried out by the direct reaction of tellurium powder and two equivalents of NaC 2H in liquid ammonia leading to Na 2TeC 2 and acetylene gas through an equilibrium containing the assumed NaTeC 2H molecules besides the reactants and the products. The resultingmore » disordered crystalline materials were characterized by X-ray diffraction and Raman spectroscopy. Implications of these new syntheses on the synthesis of other ternary acetylides with metalloid elements and transition metals are also discussed.« less

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

Bičiūnas, A.; Arlauskas, A.; Adamonis, J.

We report on terahertz (THz) emission from tellurium crystal surfaces excited by femtosecond optical pulses. Measurements were performed on three differently cut Te samples and with different wavelength optical excitation pulses. THz pulse amplitude dependences on the azimuthal angle measured at various excitation wavelengths have evidenced that three different mechanisms are responsible for THz generation in tellurium: second order nonlinear optical rectification effect, dominating at lower excitation photon energies, as well as transverse and ordinary photo-Dember effects, which emerge at energies larger than 0.9 eV. The shapes of the azimuthal angle dependences were also explained by theoretical model.

Effects of heteroatom substitution in conjugated heterocyclic compounds on photovoltaic performance: from sulfur to tellurium.

PubMed

Park, Y S; Kale, T S; Nam, C-Y; Choi, D; Grubbs, R B

2014-07-28

We report a general strategy for fine-tuning the bandgap of donor-acceptor-donor based organic molecules by modulating the electron-donating ability of the donor moiety by changing the benzochalcogenophene donor groups from benzothiophenes to benzoselenophenes to benzotellurophenes. These molecules show red-shifts in absorption and external quantum efficiency maxima from sulfur to selenium to tellurium. In bulk heterojunction solar cell devices, the benzoselenophene derivative shows a power conversion efficiency as high as 5.8% with PC61BM as the electron acceptor.

Critical Technology Events in the Development of the Stinger and Javelin Missile Systems: Project Hindsight Revisited

DTIC Science & Technology

2006-07-01

detector that operated at the mid-infrared made of InSb and another detector that operated at the near ultraviolet (UV) made of cadmium sulphide .26 The IR... mercury cadmium telluride (MCT) detectors, operating in the long-wave IR region of 8– 12 microns. The detectors were scanned at 30Hz in a bi-directional...of cadmium-tellurium and mercury -tellurium (termed mercury cadmium telluride or HgCdTe). Note the contrast with the CLU’s IR system,76 which is a

Absorption characteristics of anions (I-, Br-, and Te2-) into zeolite in molten LiCl-KCl eutectic salt

NASA Astrophysics Data System (ADS)

Uozumi, Koichi; Sugihara, Kei; Kinoshita, Kensuke; Koyama, Tadafumi; Tsukada, Takeshi; Terai, Takayuki; Suzuki, Akihiro

2014-04-01

The behaviors of anion fission product (FP) elements to be absorbed into zeolite in molten LiCl-KCl eutectic salt were studied using iodine, bromine, and tellurium. First, the type-A zeolite was selected as the most suitable type of zeolite among type-A, type-X, and type-Y zeolites through experiments in which zeolites were heated together with LiCl-KCl-KI salt. As the next step, experiments in which the type-A zeolite was immersed in molten LiCl-KCl salt containing various concentrations of iodine, bromine, or tellurium were performed. The degree of absorption of the anion FP elements was evaluated using the separation factor (SF) value versus chlorine. Although the SF values for iodine and tellurium were higher than 1.0, which meant that these elements were absorbed into the type-A zeolite more intensively than chlorine in the salt, the corresponding value for bromine was approximately 1.0. The effects of coexisting cation FPs were also examined using cesium, strontium, and neodymium, and it was revealed that the SF values for iodine were less than those in the case without cation addition. On the other hand, the SF values for tellurium were not affected by the coexistence of cesium and strontium. Finally, the feasibility of the present pyroprocess flowsheet was evaluated by calculating the inventory of each anion FP in an electrorefiner based on the obtained SF values instead of temporary values for the anion FPs absorption, which were set due to lack of experimental data.

Continuous reduction of tellurite to recoverable tellurium nanoparticles using an upflow anaerobic sludge bed (UASB) reactor.

PubMed

Ramos-Ruiz, Adriana; Sesma-Martin, Juan; Sierra-Alvarez, Reyes; Field, Jim A

2017-01-01

According to the U.S. Department of Energy and the European Union, tellurium is a critical element needed for energy and defense technology. Thus methods are needed to recover tellurium from waste streams. The objectives of this study was to determine the feasibility of utilizing upflow anaerobic sludge bed (UASB) reactors to convert toxic tellurite (Te IV ) oxyanions to non-toxic insoluble elemental tellurium (Te 0 ) nanoparticles (NP) that are amendable to separation from aqueous effluents. The reactors were supplied with ethanol as the electron donating substrate to promote the biological reduction of Te IV . One reactor was additionally amended with the redox mediating flavonoid compound, riboflavin (RF), with the goal of enhancing the bioreduction of Te IV . Its performance was compared to a control reactor lacking RF. The continuous formation of Te 0 NPs using the UASB reactors was found to be feasible and remarkably improved by the addition of RF. The presence of this flavonoid was previously shown to enhance the conversion rate of Te IV by approximately 11-fold. In this study, we demonstrated that this was associated with the added benefit of reducing the toxic impact of Te IV towards the methanogenic consortium in the UASB and thus enabled a 4.7-fold higher conversion rate of the chemical oxygen demand. Taken as a whole, this work demonstrates the potential of a methanogenic granular sludge to be applied as a bioreactor technology producing recoverable Te 0 NPs in a continuous fashion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Tellurium tetrachloride and diphenyl ditelluride cause cytotoxicity in rat hippocampal astrocytes.

PubMed

Roy, Shalini; Hardej, Diane

2011-10-01

Tellurium tetrachloride (TeCl(4)) and diphenyl ditelluride (DPDT) cytotoxicity, was investigated in rat astrocytes. Concentrations of 0.24-250μM (24h) were tested for viability using MTT(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) and trypan blue exclusion. MTT showed significant decreases at all concentrations tested for both compounds. Significant decreases in viability were seen in 1.95-250μM of DPDT and 0.97-250μM of TeCl(4) with trypan blue exclusion. The LC(50) for both compounds was 62.5μM. Light and scanning microscopy confirm toxicity observed at higher concentrations. Thiobarbituric acid reactive substances (TBARs) assay, TUNEL, cytochrome c and caspase release were carried out. No significant increase in TBARS with either agent was observed (15.625-62.5μM). TUNEL and cytochrome c assays demonstrated apoptosis in TeCl(4) treated cells (31.25-125μM). Non-apoptotic cells were observed in DPDT treated cells. Studies of caspase 3/7 and caspase 9 indicated increased activity in TeCl(4) but not in DPDT treated cells. Optical Emission Spectroscopy of DPDT and TeCl(4) treated cells demonstrated significant accumulation of elemental tellurium in all treatment groups (31.25-125μM). We conclude that DPDT and TeCl(4) are cytotoxic to astrocytes. TeCl(4) treated cells die via the intrinsic apoptotic pathway. Accumulation of tellurium occurs with both compounds, but results in different mechanisms of cell death. Copyright © 2011 Elsevier Ltd. All rights reserved.

Beneficial Effect of S-Filling on Thermoelectric Properties of S x Co4Sb11.2Te0.8 Skutterudite

NASA Astrophysics Data System (ADS)

Wang, Hongtao; Duan, Bo; Bai, Guanghui; Li, Jialiang; Yu, Yue; Yang, Houjiang; Chen, Gang; Zhai, Pengcheng

2018-06-01

In this work, Te-doped and S-filled S x Co4Sb11.2Te0.8 ( x = 0.1, 0.15, 0.2, 0.25, 0.3, 0.4) skutterudite compounds have been prepared using solid state reaction and spark plasma sintering. Thermoelectric measurements of the consolidated samples were examined in a temperature range of 300-850 K, and the influences of S-addition on the thermoelectric properties of S x Co4Sb11.2Te0.8 skutterudites are systematically investigated. The results indicate that the addition of sulfur and tellurium is effective in reducing lattice thermal conductivity due to the point-defect scattering caused by tellurium substitutions and the cluster vibration brought by S-filling. The solubility of tellurium in skutterudites is enhanced with sulfur addition via charge compensation. The thermal conductivity decreases with increasing sulfur content. The highest figure of merit, ZT = 1.5, was obtained at 850 K for S0.3Co4Sb11.2Te0.8 sample, because of the low lattice thermal conductivity.

Microbial-assisted synthesis and evaluation the cytotoxic effect of tellurium nanorods.

PubMed

Forootanfar, Hamid; Amirpour-Rostami, Sahar; Jafari, Mandana; Forootanfar, Amir; Yousefizadeh, Zahra; Shakibaie, Mojtaba

2015-04-01

The present study was designed to isolate bacterial strain capable of tellurium nanorods' (Te NRs) production followed by purification and evaluation of the cytotoxic effect of Te NRs. Among 25 environmental samples collected for screening of Te NR-producer bacterial strains one bacterial colony (isolated from hot spring and identified as Pseudomonas pseudoalcaligenes strain Te) was selected and applied for biosynthesis of Te NRs. Thereafter, an organic-aqueous partitioning system was applied for the purification of the biogenic Te NRs and the purified Te NRs were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction spectroscopy (XRD), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR) techniques. The cytotoxic effect of biologically synthesized Te NRs and potassium tellurite on four cell lines of MCF-7, HT1080, HepG2 and A549 was then determined using the MTT assay method. The obtained results revealed lower toxicity for the rod-shaped biogenic tellurium nanostructures (~22nm diameter by 185nm length) compared to K2TeO3. Copyright © 2014. Published by Elsevier B.V.

Observation of amorphous to crystalline phase transformation in Te substituted Sn-Sb-Se thin films

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

Chander, Ravi, E-mail: rcohri@yahoo.com

2015-05-15

Thin films of Sn-Sb-Se-Te (8 ≤ x ≤ 14) chalcogenide system were prepared by thermal evaporation technique using melt quenched bulk samples. The as-prepared thin films were found amorphous as evidenced from X-ray diffraction studies. Resistivity measurement showed an exponential decrease with temperature upto critical temperature (transition temperature) beyond which a sharp decrease was observed and with further increase in temperature showed an exponential decrease in resistivity with different activation energy. The transition temperature showed a decreasing trend with tellurium content in the sample. The resistivity measurement during cooling run showed no abrupt change in resistivity. The resistivity measurements ofmore » annealed films did not show any abrupt change revealing the structural transformation occurring in the material. The transition width showed an increase with tellurium content in the sample. The resistivity ratio showed two order of magnitude improvements for sample with higher tellurium content. The observed transition temperature in this system was found quite less than already commercialized Ge-Sb-Te system for optical and electronic memories.« less

125Te NMR Probes of Tellurium Oxide Crystals: Shielding-Structure Correlations.

PubMed

Garaga, Mounesha N; Werner-Zwanziger, Ulrike; Zwanziger, Josef W

2018-01-16

The local environments around tellurium atoms in a series of tellurium oxide crystals were probed by 125 Te solid-state NMR spectroscopy. Crystals with distinct TeO n units (n from 3 to 6), including Na 2 TeO 3 , α-TeO 2 and γ-TeO 2 , Te 2 O(PO 4 ) 2 , K 3 LaTe 2 O 9 , BaZnTe 2 O 7 , and CsYTe 3 O 8 were studied. The latter four were synthesized through a solid-state process. X-ray diffraction was used to confirm the successful syntheses. The 125 Te chemical shift was found to exhibit a strong linear correlation with the Te coordination number. The 125 Te chemical-shift components (δ 11 , δ 22 , and δ 33 ) of the TeO 4 units were further correlated to the O-Te-O-bond angles. With the aid of 125 Te NMR, it is likely that these relations can be used to estimate the coordination states of Te atoms in unknown Te crystals and glasses.

Evaluation of the Content of Antimony, Arsenic, Bismuth, Selenium, Tellurium and Their Inorganic Forms in Commercially Baby Foods.

PubMed

Ruiz-de-Cenzano, M; Rochina-Marco, A; Cervera, M L; de la Guardia, M

2017-12-01

Baby foods, from the Spanish market and prepared from meat, fish, vegetables, cereals, legumes, and fruits, were analyzed to obtain the concentration of antimony (Sb), arsenic (As), bismuth (Bi), and tellurium (Te) as toxic elements and selenium (Se) as essential element. An analytical procedure was employed based on atomic fluorescence spectroscopy which allowed to obtain accurate data at low levels of concentration. Values of 14 commercial samples, expressed in nanograms per gram fresh weight, ranged for Sb 0.66-6.9, As 4.5-242, Te 1.35-2.94, Bi 2.18-4.79, and Se 5.4-109. Additionally, speciation studies were performed based on data from a non-chromatographic screening method. It was concluded that tellurium and bismuth were mainly present as inorganic forms and selenium as organic form, and antimony and arsenic species depend on the ingredients of each baby food. Risk assessment considerations were made by comparing dietary intake of the aforementioned elements through the consumption of one baby food portion a day and recommended or tolerable guideline values.

Luminescent Tellurium-Doped Cadmium Sulfide Electrodes as Probes of Semiconductor Excited-State Deactivation Processes in Photoelectrochemical Cells.

DTIC Science & Technology

1980-08-12

photocurrent and emission intensity. Whereas CdS:Te electrochemistry consisted of oxidation of an electrolyte 2+ reductant, ZnO underwent photoanodic...employed n- and 1 3 2,3 3 3,4p-type GaPl’ n-type ZnO , n-type CdS , and n- and p-type GaAs. We have focussed our attention recently on n-type, tellurium...should point out that our treatment of Or and 0x is not without precedent. Both GaP- and ZnO -based PECs have been examined in this regard.l12 The

Photoluminescence Study of N-Type Thermal Conversion in Semi-Insulating GaAs.

DTIC Science & Technology

1982-12-01

free electron to the crystal. For example, in GaAs, a tellurium atom on an arsenic site (TeAs) or a silicon atom on a gallium site (SiGa) are donor atoms...Photoconductivity Photoluminescenc Silicon, SiGa 5.81 6.80 Germanium, GeGa 6.08 Sulfur, SAs 6.10 Selenium, SeAs 5.89 6.10 Tellurium , TeAs When an electron...34 to the neutral donor or acceptor (Ref 16:15). The following excitonic com- plexes have been observed in GaAs: (i) exciton bound to a neutron donor at

Fibre laser based on tellurium-doped active fibre

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

Alyshev, S V; Ryumkin, K E; Shubin, A V

2014-02-28

We have studied the lasing properties of tellurium-doped germanosilicate fibre, identified its gain and excited-state absorption bands, and assessed the effect of cooling to low temperature (77 K) on the bands. The excitation spectrum of the near-IR luminescence in the fibre has been measured. Lasing at 1.55 mm has been demonstrated for the first time in this gain medium at liquidnitrogen temperature and pump wavelengths of 1.064 and 1.085 mm. The measured Raman spectrum of the fibre provides some insight into the structure of the near-IR luminescence centre. (letters)

Plasmid-determined resistance to tellurium compounds.

PubMed Central

Summers, A O; Jacoby, G A

1977-01-01

Transferable plasmids in gram-negative bacteria that confer resistance to potassium tellurite or tellurate were found. This re-istance was distinct from resistance to mercury, silver, or arsenic compounds and was unrelated to antibiotic resistance. In Escherichia coli, plasmids determine a 100-fold increase in the minimal inhibitory concentration for tellurite and a 10-fold increase in tellurate resistance. Many, but not all, of the plasmids belong to incompatibility group S. In Pseudomonas aeruginosa, tellurium resistance is specifically associated with incompatibility group P-2 and involves a 5- to 10-fold increase in tellurite or tellurate resistance. Images PMID:401494

Study of tellurium precipitates in CdTe crystals

NASA Technical Reports Server (NTRS)

Jayatirtha, H. N.; Henderson, D. O.; Burger, A.; Volz, M. P.

1993-01-01

The effect of tellurium precipitates was studied in medium resistivity (10 exp 3-10 exp 6 ohm cm) undoped and Cl-doped CdTe using differential scanning calorimetry (DSC) and mid-infrared spectroscopy and the results were correlated with near-infrared microscopy photographs. When present in a significant quantity (about 0.25 wt pct), we show that Te precipitates are detectable using DSC measurements. In the mid-infrared, the contribution of the absorption by free-carriers is negligible, and therefore, the effect of the Te precipitates in these crystals can be considered uncoupled from the effects of Cd vacancies.

IR luminescence of tellurium-doped silica-based optical fibre

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

Dianov, Evgenii M; Alyshev, S V; Shubin, Aleksei V

2012-03-31

Tellurium-doped germanosilicate fibre has been fabricated by the MCVD process. In contrast to Te-containing glasses studied earlier, it has a broad luminescence band (full width at half maximum of {approx}350 nm) centred at 1500 nm, with a lifetime of {approx}2 {mu}s. The luminescence of the fibre has been studied before and after gamma irradiation in a {sup 60}Co source to 309 and 992 kGy. The irradiation produced a luminescence band around 1100 nm, with a full width at half maximum of {approx}400 nm and lifetime of {approx}5 {mu}s. (letters)

Decomposition and reactivity of tellurium alkyls in the liquid and gas phases; dihex-5-enyltellurium and dipent-4-enyltellurium as mechanistic probes

NASA Astrophysics Data System (ADS)

Bell, William; McQueen, A. Ewan D.; Walton, John C.; Foster, Douglas F.; Cole-Hamilton, David J.; Hails, Janet E.

1992-02-01

The new tellurium alkyls, dihex-5-enyltellurium and dipent-4-enyltellurium have been prepared and pyrolysed in the gas and liquid phases. in the liquid phase, at 200°C some decomposition occurs but the main isolated products are the tellurium alkyls, bis(cyclopentylmethyl)tellurium and 2-methyltelluracyclopentane respectively. A further product, cyclopentylmethylhex-5-enyltellurium is observed as an intermediate in the rearrangement of dihex-5-enyltellurium, whilst (2-telluracyclopentylmethyl)pent-4-enyltellurium together with pent-1-ene and 1,4-pentadiene is obtained from dipent-4-enyltellurium. These products are interpreted as providing direct evidence for initial homolytic cleavage of the Te-C bonds followed by cyclisation of some of the formed radicals and radical chain reactions. In the gas phase, at 500°C similar products to those obtained in the liquid phase are formed from dipent-4-enyltellurium, although not compounds containing more than one Te atom. Dihex-5-enyltellurium, however, decomposes completely in the gas phase at 700°C to give a mixture of hydrocarbons. Substantial quantities of methylcyclopentane and methylenecyclopentane again confirm that a free radical pathway makes a major contribution to the mechanism. The origin of the other products, especially cyclohexene (the major C 6 product) and cyclohexane is also interpreted in terms of a free radical mechanism leading to the 6-tellurahex-1-enyl radical which cyclises to give the 3-telluracycloheptylradical. This radical rearranges to cyclohexyl Te· which in turn acts as the source of cyclohexene and cyclohexane by H· abstraction or addition. There is little evidence that mechanisms other than free radical operate for decomposition of these metal alkyls.

A new tellurium-containing amphiphilic molecule induces apoptosis in HCT116 colon cancer cells.

PubMed

Du, Peng; Saidu, Nathaniel Edward Bennett; Intemann, Johanna; Jacob, Claus; Montenarh, Mathias

2014-06-01

Chalcogen-based redox modulators over the years have attracted considerable attention as anti-cancer agents. New selenium- and tellurium-containing compounds with a polar head group and aryl-groups of various lengths have recently been reported as biologically active in several organisms. In the present study, we used the most active of the tellurium compound DP41, and its selenium counterpart DP31 to investigate their effects on the human cancer cell line HCT116. Cells were treated with DP41 or DP31 and the formation of superoxide radicals was determined using dihydroethidium. Cell cycle analysis and apoptosis was determined by cytofluorimetry. Proteins involved in ER signaling and apoptosis were determined by Western blot analysis and fluorescence microscopy. With 50μM of DP41, we observed an increase in O2(-) formation. There was, however, no such increase in O2(-) after treatment with the corresponding selenium compound under the same conditions. In the case of DP41, the production of O2(-) radicals was followed by an up-regulation of Nrf2, HO-1, phospho-eIF2α and ATF4. CHOP was also induced and cells entered apoptosis. Unlike the cancer cells, normal retinal epithelial ARPE-19 cells did not produce elevated levels of O2(-) radicals nor did they induce the ER signaling pathway or apoptosis. The tellurium-containing compound DP41, in contrast to the corresponding selenium compound, induces O2(-) radical formation and oxidative and ER stress responses, including CHOP activation and finally apoptosis. These results indicate that DP41 is a redox modulating agent with promising anti-cancer potentials. Copyright © 2014 Elsevier B.V. All rights reserved.

Electrical, structural and optical properties of tellurium thin films on silicon substrate

NASA Astrophysics Data System (ADS)

Arora, Swati; Vijay, Y. K.

2018-05-01

Tellurium (Te) thin films of various thicknesses (200nm, 275nm, 350nm & 500nm) were prepared on Silicon (Si) using thermal evaporation at vacuum of 10-5 torr. It is observed that the resistivity decreases exponentially with the Increases Temperature. A direct band gap between 0.368 eV to 0.395 eV is obtained at different temperatures with Four Probe Method which shows that when we increase the thickness of material the band gap will exponentially decreases. Samples were analysed through X-ray diffraction and atomic force microscopy to attain complete and reliable micro structural in order.

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

Peng, Hua; College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024; Kioussis, Nicholas, E-mail: nick.kioussis@csun.edu

Using ab initio based calculations, we have calculated the intrinsic lattice thermal conductivity of chiral tellurium. We show that the interplay between the strong covalent intrachain and weak van der Waals interchain interactions gives rise to the phonon band gap between the lower and higher optical phonon branches. The underlying mechanism of the large anisotropy of the thermal conductivity is the anisotropy of the phonon group velocities and of the anharmonic interatomic force constants (IFCs), where large interchain anharmonic IFCs are associated with the lone electron pairs. We predict that tellurium has a large three-phonon scattering phase space that resultsmore » in low thermal conductivity. The thermal conductivity anisotropy decreases under applied hydrostatic pressure.« less

Isolatable organophosphorus(III)-tellurium heterocycles.

PubMed

Nordheider, Andreas; Chivers, Tristram; Schön, Oliver; Karaghiosoff, Konstantin; Athukorala Arachchige, Kasun S; Slawin, Alexandra M Z; Woollins, J Derek

2014-01-13

A new structural arrangement Te3 (RP(III) )3 and the first crystal structures of organophosphorus(III)-tellurium heterocycles are presented. The heterocycles can be stabilized and structurally characterized by the appropriate choice of substituents in Tem (P(III) R)n (m=1: n=2, R=OMes* (Mes*=supermesityl or 2,4,6-tri-tert-butylphenyl); n=3, R=adamantyl (Ad); n=4, R=ferrocene (Fc); m=n=3: R=trityl (Trt), Mesor by the installation of a P(V) 2 N2 anchor in RP(III) [TeP(V) (tBuN)(μ-NtBu)]2 (R=Ad, tBu). Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Molecular organometallic resists for EUV (MORE): Reactivity as a function of metal center (Bi, Sb, Te and Sn)

NASA Astrophysics Data System (ADS)

Sitterly, Jacob; Murphy, Michael; Grzeskowiak, Steven; Denbeaux, Greg; Brainard, Robert L.

2018-03-01

This paper describes the photoreactivity of six organometallic complexes of the type PhnMX2 containing bismuth, antimony and tellurium, where n = 3 for bismuth and antimony and n = 2 for tellurium, and where X = acetate (O2CCH3) or pivalate (O2CC(CH3)3). These compounds were exposed to EUV light to monitor photodecomposition via in situ mass spectral analysis of the primary outgassing products of CO2, benzene and phenol. This paper explores the effect of metal center and carboxylate ligand on the EUV reactivity of these EUV photoresists.

Rapid and sensitive determination of tellurium in soil and plant samples by sector-field inductively coupled plasma mass spectrometry.

PubMed

Yang, Guosheng; Zheng, Jian; Tagami, Keiko; Uchida, Shigeo

2013-11-15

In this work, we report a rapid and highly sensitive analytical method for the determination of tellurium in soil and plant samples using sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). Soil and plant samples were digested using Aqua regia. After appropriate dilution, Te in soil and plant samples was directly analyzed without any separation and preconcentration. This simple sample preparation approach avoided to a maximum extent any contamination and loss of Te prior to the analysis. The developed analytical method was validated by the analysis of soil/sediment and plant reference materials. Satisfactory detection limits of 0.17 ng g(-1) for soil and 0.02 ng g(-1) for plant samples were achieved, which meant that the developed method was applicable to studying the soil-to-plant transfer factor of Te. Our work represents for the first time that data on the soil-to-plant transfer factor of Te were obtained for Japanese samples which can be used for the estimation of internal radiation dose of radioactive tellurium due to the Fukushima Daiichi Nuclear Power Plant accident. Copyright © 2013 Elsevier B.V. All rights reserved.

Tellurium-nanowire-coated glassy carbon electrodes for selective and sensitive detection of dopamine.

PubMed

Tsai, Hsiang-Yu; Lin, Zong-Hong; Chang, Huan-Tsung

2012-05-15

Tellurium-nanowire-coated glassy carbon electrodes (TNGCEs) have been fabricated and employed for selective and sensitive detection of dopamine (DA). TNGCEs were prepared by direct deposition of tellurium nanowires, 600 ± 150 nm in length and 16 ± 3 nm in diameter, onto glassy carbon electrodes, which were further coated with Nafion to improve their selectivity and stability. Compared to the GCE, the TNGCE is more electroactive (by approximately 1.9-fold) for DA, and its selectivity toward DA over ascorbic acid (AA) and uric acid (UA) is also greater. By applying differential pulse voltammetry, at a signal-to-noise ratio of 3, the TNGCE provides a limit of detection of 1 nM for DA in the presence of 0.5mM AA and UA. Linearity (R(2)=0.9955) of the oxidation current at 0.19 V against the concentration of DA is found over the range 5 nM-1 μM. TNGCEs have been applied to determine the concentration of dopamine to be 0.59 ± 0.07 μM in PC12 cells. Copyright © 2012 Elsevier B.V. All rights reserved.

Aspects of a Distinct Cytotoxicity of Selenium Salts and Organic Selenides in Living Cells with Possible Implications for Drug Design.

PubMed

Estevam, Ethiene Castellucci; Witek, Karolina; Faulstich, Lisa; Nasim, Muhammad Jawad; Latacz, Gniewomir; Domínguez-Álvarez, Enrique; Kieć-Kononowicz, Katarzyna; Demasi, Marilene; Handzlik, Jadwiga; Jacob, Claus

2015-07-31

Selenium is traditionally considered as an antioxidant element and selenium compounds are often discussed in the context of chemoprevention and therapy. Recent studies, however, have revealed a rather more colorful and diverse biological action of selenium-based compounds, including the modulation of the intracellular redox homeostasis and an often selective interference with regulatory cellular pathways. Our basic activity and mode of action studies with simple selenium and tellurium salts in different strains of Staphylococcus aureus (MRSA) and Saccharomyces cerevisiae indicate that such compounds are sometimes not particularly toxic on their own, yet enhance the antibacterial potential of known antibiotics, possibly via the bioreductive formation of insoluble elemental deposits. Whilst the selenium and tellurium compounds tested do not necessarily act via the generation of Reactive Oxygen Species (ROS), they seem to interfere with various cellular pathways, including a possible inhibition of the proteasome and hindrance of DNA repair. Here, organic selenides are considerably more active compared to simple salts. The interference of selenium (and tellurium) compounds with multiple targets could provide new avenues for the development of effective antibiotic and anticancer agents which may go well beyond the traditional notion of selenium as a simple antioxidant.

Ultrafast synthesis of Te nanorods as cathode materials for lithium-tellurium batteries

NASA Astrophysics Data System (ADS)

Huang, Dekang; Li, Shu; Xiao, Xin; Cao, Minglei; Gao, Lin; Xiang, Yong-Gang; Chen, Hao; Shen, Yan

2017-12-01

Recently, tellurium has been regarded as a promising cathode material for rechargeable lithium-ion batteries due to its high theoretical volumetric capacity. However, a plethora of research are focusing on impregnating the tellurium into porous carbon materials by the thermal-diffusion method, which would consume large amounts of energy and take prolonged time. Herein, a carbon and binder-free cathode with 100% Te is fabricated by a facile galvanic replacement method on a nickle foam. Driven by the large electrochemical potential difference between Ni and Te, desirable amounts of Te can be obtained in just 10 min with no need of energy input. Li-Te batteries constructed by the as-obtained cathode show relatively good performance in DMSO solvent. To further elevate the performance of this battery especially at low current density, commercial carbon cloth is added between the separator and Te electrode as an interlayer. The cell with interlayer delivers a gravimetric capacity of 116.2 mAh g-1 after 70 cycles at the current density of 100 mA g-1, which is 2.8 times as high as that of a cell without interlayer (40.4 mAh g-1).

REDUCTION OF INORGANIC COMPOUNDS WITH MOLECULAR HYDROGEN BY MICROCOCCUS LACTILYTICUS I.

PubMed Central

Woolfolk, C. A.; Whiteley, H. R.

1962-01-01

Woolfolk, C. A. (University of Washington, Seattle) and H. R. Whiteley. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements. J. Bacteriol. 84:647–658. 1962.—Extracts of Micrococcus lactilyticus (Veillonella alcalescens) oxidize molecular hydrogen at the expense of certain compounds of arsenic, bismuth, selenium, tellurium, lead, thallium, vanadium, manganese, iron, copper, molybdenum, tungsten, osmium, ruthenium, gold, silver, and uranium, as well as molecular oxygen. Chemical and manometric data indicate that the following reductions are essentially quantitative: arsenate to arsenite, pentavalent and trivalent bismuth to the free element, selenite via elemental selenium to selenide, tellurate and tellurite to tellurium, lead dioxide and manganese dioxide to the divalent state, ferric to ferrous iron, osmium tetroxide to osmate ion, osmium dioxide and trivalent osmium to the metal, uranyl uranium to the tetravalent state, vanadate to the level of vanadyl, and polymolybdate ions to molybdenum blues with an average valence for molybdenum of +5. The results of a study of certain other hydrogenase-containing bacteria with respect to their ability to carry out some of the same reactions are also presented. PMID:14001842

Anisotropic Light Diffraction by Ultrasound in Crystals with Strong Acoustic Anisotropy

NASA Astrophysics Data System (ADS)

Voloshin, Andrey S.; Balakshy, Vladimir I.

In modern acousto-optics, crystalline materials are used predominantly for manufacturing acousto-optic instruments. Among these materials, such crystals as paratellurite, tellurium, calomel, TAS and some others occupy a prominent place, which are distinguished by exceptionally large anisotropy of acoustic properties. In this work, the influence of acoustic beam energy walk-off on characteristics of Bragg diffraction of light is studied by the example of tellurium crystal. It is shown that the walk-off can substantially change angular and frequency ranges, resulting in their narrowing or broadening subject to position of the operating point in the Bragg angle frequency characteristic. Coefficients of broadening are introduced for characterization of this effect.

Intrinsic two-dimensional states on the pristine surface of tellurium

NASA Astrophysics Data System (ADS)

Li, Pengke; Appelbaum, Ian

2018-05-01

Atomic chains configured in a helical geometry have fascinating properties, including phases hosting localized bound states in their electronic structure. We show how the zero-dimensional state—bound to the edge of a single one-dimensional helical chain of tellurium atoms—evolves into two-dimensional bands on the c -axis surface of the three-dimensional trigonal bulk. We give an effective Hamiltonian description of its dispersion in k space by exploiting confinement to a virtual bilayer, and elaborate on the diminished role of spin-orbit coupling. These intrinsic gap-penetrating surface bands were neglected in the interpretation of seminal experiments, where two-dimensional transport was otherwise attributed to extrinsic accumulation layers.

Effect of tellurium concentration on the structural, electronic and mechanical properties of beryllium sulphide: A DFT approach

NASA Astrophysics Data System (ADS)

Iyorzor, B. E.; Babalola, M. I.; Adetunji, B. I.; Bakare, F. O.

2018-05-01

The structural, electronic and mechanical properties of Be{S}1-xT{e}x are studied within the concentration range of 0≤slant x≤slant 1 using first-principles plane–wave Pseudopotential density functional theory (DFT) approach. We have used generalized gradient approximation (GGA) to treat the exchange-correlation potentials. The elastic constants, bulk, shear and Young’s moduli, Poisson’s ratio, and Zener’s anisotropic factors are calculated. The results were found to be in agreement with other available theoretical and experimental values. It was also observed that the existence and increase of Tellurium concentration decreases the hardness of the alloy.

Evaluation of excitation functions of proton and deuteron induced reactions on enriched tellurium isotopes with special relevance to the production of iodine-124.

PubMed

Aslam, M N; Sudár, S; Hussain, M; Malik, A A; Shah, H A; Qaim, S M

2010-09-01

Cross-section data for the production of medically important radionuclide (124)I via five proton and deuteron induced reactions on enriched tellurium isotopes were evaluated. The nuclear model codes, STAPRE, EMPIRE and TALYS, were used for consistency checks of the experimental data. Recommended excitation functions were derived using a well-defined statistical procedure. Therefrom integral yields were calculated. The various production routes of (124)I were compared. Presently the (124)Te(p,n)(124)I reaction is the method of choice; however, the (125)Te(p,2n)(124)I reaction also appears to have great potential.

Strong nonlinear photonic responses from microbiologically synthesized tellurium nanocomposites

USGS Publications Warehouse

Liao, K.-S.; Wang, Jingyuan; Dias, S.; Dewald, J.; Alley, N.J.; Baesman, S.M.; Oremland, R.S.; Blau, W.J.; Curran, S.A.

2010-01-01

A new class of nanomaterials, namely microbiologically-formed nanorods composed of elemental tellurium [Te(0)] that forms unusual nanocomposites when combined with poly(m-phenylenevinylene-co-2,5-dioctoxy-phenylenevinylene) (PmPV) is described. These bio-nanocomposites exhibit excellent broadband optical limiting at 532 and 1064 nm. Nonlinear scattering, originating from the laser induced solvent bubbles and microplasmas, is responsible for this nonlinear behavior. The use of bacterially-formed Te(0) when combined with an organic chemical host (e.g., PmPV) is a new green method of nanoparticle syntheses. This opens the possibilities of using unique, biologically synthesized materials to advance future nanoelectronic and nanophotonic applications. ?? 2009 Elsevier B.V. All rights reserved.

Cadmium telluride in tellurium—cadmium films consisting of ultradispersed particles

NASA Astrophysics Data System (ADS)

Tuleushev, Yu. Zh.; Volodin, V. N.; Migunova, A. A.; Lisitsyn, V. N.

2015-08-01

Solid solutions of tellurium in cadmium, cadmium in tellurium, and cadmium in cadmium telluride synthesized during sputtering are formed for the first time by ion-plasma sputtering and the codeposition of ultradispersed Te and Cd particle fluxes onto substrates moving with respect to the fluxes. This fact supports thermofluctuation melting and coalescence of small particles. The lattice parameter of cadmium telluride, which coexists with an amorphous solid solution of tellurium in cadmium in a coating, is smaller than the tabulated value and reaches it when the cadmium concentration in a coating increases to 70 at %. The lattice parameter of the fcc lattice of cadmium telluride increases with the cadmium concentration in a coating according to the linear relation a = 0.0002CCd + 0.6346 nm (where CCd is the cadmium concentration in the coating, at %), which is likely to indicate a certain broadening of the homogeneity area. The estimation of the particle size shows that the cadmium telluride grain size is 10-15 nm, which implies that the coatings are nanocrystalline. The absorption and transmission spectra of the tellurium—cadmium films at the fundamental absorption edge demonstrate that their energy gaps are larger than that of stoichiometric CdTe, which can be explained by the experimental conditions of crystal structure formation.

Tellurium as a valuable tool for studying the prokaryotic origins of mitochondria.

PubMed

Pontieri, Paola; De Stefano, Mario; Massardo, Domenica Rita; Gunge, Norio; Miyakawa, Isamu; Sando, Nobundo; Pignone, Domenico; Pizzolante, Graziano; Romano, Roberta; Alifano, Pietro; Del Giudice, Luigi

2015-04-01

Mitochondria are eukaryotic organelles which contain the own genetic material and evolved from free-living Eubacteria, namely hydrogen-producing Alphaproteobacteria. Since 1965, biologists provided, by research at molecular level, evidence for the prokaryotic origins of mitochondria. However, determining the precise origins of mitochondria is challenging due to inherent difficulties in phylogenetically reconstructing ancient evolutionary events. The use of new tools to evidence the prokaryotic origin of mitochondria could be useful to gain an insight into the bacterial endosymbiotic event that resulted in the permanent acquisition of bacteria, from the ancestral cell, that through time were transformed into mitochondria. Electron microscopy has shown that both proteobacterial and yeast cells during their growth in the presence of increasing amount of tellurite resulted in dose-dependent blackening of the culture due to elemental tellurium (Te(0)) that formed large deposits either along the proteobacterial membrane or along the yeast cell wall and mitochondria. Since the mitochondrial inner membrane composition is similar to that of proteobacterial membrane, in the present work we evidenced the black tellurium deposits on both, cell wall and mitochondria of ρ(+) and respiratory deficient ρ(-) mutants of yeast. A possible role of tellurite in studying the evolutionary origins of mitochondria will be discussed. Copyright © 2015. Published by Elsevier B.V.

Resource recovery from urban stock, the example of cadmium and tellurium from thin film module recycling

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

Simon, F.-G., E-mail: franz-georg.simon@bam.de; Holm, O.; Berger, W.

2013-04-15

Highlights: ► The semiconductor layer on thin-film photovoltaic modules can be removed from the glass-plate by vacuum blast cleaning. ► The separation of blasting agent and semiconductor can be performed using flotation with a valuable yield of 55%. ► PV modules are a promising source for the recovery of tellurium in the future. - Abstract: Raw material supply is essential for all industrial activities. The use of secondary raw material gains more importance since ore grade in primary production is decreasing. Meanwhile urban stock contains considerable amounts of various elements. Photovoltaic (PV) generating systems are part of the urban stockmore » and recycling technologies for PV thin film modules with CdTe as semiconductor are needed because cadmium could cause hazardous environmental impact and tellurium is a scarce element where future supply might be constrained. The paper describes a sequence of mechanical processing techniques for end-of-life PV thin film modules consisting of sandblasting and flotation. Separation of the semiconductor material from the glass surface was possible, however, enrichment and yield of valuables in the flotation step were non-satisfying. Nevertheless, recovery of valuable metals from urban stock is a viable method for the extension of the availability of limited natural resources.« less

Proceedings 43rd Stanford Geothermal Workshop

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

Simmons, Stuart; Kirby, Stefan; Verplanck, Philip

Herein we summarize the results of an investigation dealing with the concentrations and inventories of strategic, critical and valuable materials (SCVM) in produced fluids from geothermal and hydrocarbon reservoirs (50-250° C) in Nevada and Utah. Water samples were collected from thirty-four production wells across eight geothermal fields, the Uinta Basin oil/gas province in northeast Utah, and the Covenant oil field in southwestern Utah; additional water samples were collected from six hot springs in the Sevier Thermal Belt in southwestern Utah. Most SCVM concentrations in produced waters range from <0.1 to 100 µg/kg; the main exception is lithium, which has concentrationsmore » that range from <1000 to 25,000 ug/kg. Relatively high concentrations of gallium, germanium, scandium, selenium, and tellurium are measured too. Geothermal waters contain very low concentrations of REEs, below analytical detections limits (0.01 µg/kg), but the concentrations of lanthanum, cerium, and europium range from 0.05 to 5 µg/kg in Uinta basin waters. Among the geothermal fields, the Roosevelt Hot Spring reservoir appears to have the largest inventories of germanium and lithium, and Patua appears to have the largest inventories of gallium, scandium, selenium, and tellurium. By comparison, the Uinta basin has larger inventories of gallium. The concentrations of gallium, germanium, lithium, scandium, selenium, and tellurium in produced waters appear to be partly related to reservoir temperature and concentrations of total dissolved salts. The relatively high concentration and large inventory of lithium occurring at Roosevelt Hot Springs may be related to granitic-gneissic crystalline rocks, which host the reservoir. Analyses of calcite scales from Dixie Valley indicate enrichments in cobalt, gallium, gold, palladium, selenium and tellurium, and these metals appear to be depositing at deep levels in production wells due to boiling. Comparisons with SCVM mineral deposits suggest that brines in sedimentary basins, or derived from lacustrine evaporites, enable aqueous transport of gallium, germanium, and lithium.« less

Speciation and determination of ultra trace amounts of inorganic tellurium in environmental water samples by dispersive liquid-liquid microextraction and electrothermal atomic absorption spectrometry.

PubMed

Najafi, Nahid Mashkouri; Tavakoli, Hamed; Alizadeh, Reza; Seidi, Shahram

2010-06-18

A simple and powerful method has been developed for the rapid and selective determination of Te(IV) and Te(VI), employing dispersive liquid-liquid microextraction combined with electrothermal atomic absorption spectrometry using palladium as permanent modifier. Under acidic conditions pH 1, only Te(IV) can form a complex with ammonium pyrrolidine dithiocarbamate (APDC) and therefore be extracted into fine droplets of carbon tetrachloride (extraction solvent) which are dispersed with ethanol into the water sample solution. After centrifugation, Te(IV) was determined in the sedimented organic phase while Te(VI) remained in the aqueous phase. Total inorganic tellurium was determined after the reduction of the Te(VI) to Te(IV). Te(VI) was calculated as the difference between the measured total inorganic tellurium and Te(IV) content. The effective parameters for improving the efficiency of microextraction process were investigated by using experimental and central composite designs. Under optimal conditions the enrichment factor was 125 and the calibration graph was linear in the range of 0.015-1 ng mL(-1) with detection limit and characteristic mass of 0.004 ng mL(-1) and 0.033 pg, respectively. The relative standard deviation for 0.5 ng mL(-1) of tellurium measurement was 3.6% (n=6) at ash and atomization temperature, 900 and 2600 degrees C, respectively. The recoveries of spiked Te(IV) and Te(VI) to the environmental water samples were 89.6-101.3% and 96.6-99.1%, respectively. The accuracy is also evaluated by applying the proposed method to certified reference material (NIST SRM 1643e), for which the result was in a good agreement with the certified values reported for this CRM (95% confidence level). 2010 Elsevier B.V. All rights reserved.

Raman and Photoluminescence Spectroscopy of Er(3+) Doped Heavy Metal Oxide Glasses

NASA Technical Reports Server (NTRS)

Dyer, Keith; Pan, Zheng-Da; Morgan, Steve

1997-01-01

The potential applications of rare-earth ion doped materials include fiber lasers which can be pumped conveniently by infrared semiconductor laser diodes. The host material systems most widely studied are fluoride crystals and glasses because fluorides have low nonradiative relaxation rates due to their lower phonon energies. However, the mechanical strength, chemical durability and temperature stability of the oxide glasses are generally much better than fluoride glasses. The objective of this research was to investigate the optical and spectroscopic properties of Er(3+)-doped lead-germanate and lead-tellurium-germanate glasses. The maximum vibrational energy of lead-tellurium-germanate glasses are in the range of 740-820/cm, intermediate between those of silicate (1150/cm) and fluoride (530/cm) glasses.

Fabrication of Te and Te-Au Nanowires-Based Carbon Fiber Fabrics for Antibacterial Applications

PubMed Central

Chou, Ting-Mao; Ke, Yi-Yun; Tsao, Yu-Hsiang; Li, Ying-Chun; Lin, Zong-Hong

2016-01-01

Pathogenic bacteria that give rise to diseases every year remain a major health concern. In recent years, tellurium-based nanomaterials have been approved as new and efficient antibacterial agents. In this paper, we developed the approach to directly grow tellurium nanowires (Te NWs) onto commercial carbon fiber fabrics and demonstrated their antibacterial activity. Those Te NWs can serve as templates and reducing agents for gold nanoparticles (Au NPs) to deposit. Three different Te-Au NWs with varied concentration of Au NPs were synthesized and showed superior antibacterial activity and biocompability. These results indicate that the as-prepared carbon fiber fabrics with Te and Te-Au NWs can become antimicrobial clothing products in the near future. PMID:26861380

Silicon-Based Thermoelectrics: Harvesting Low Quality Heat Using Economically Printed Flexible Nanostructured Stacked Thermoelectric Junctions

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

None

2010-03-01

Broad Funding Opportunity Announcement Project: UIUC is experimenting with silicon-based materials to develop flexible thermoelectric devices—which convert heat into energy—that can be mass-produced at low cost. A thermoelectric device, which resembles a computer chip, creates electricity when a different temperature is applied to each of its sides. Existing commercial thermoelectric devices contain the element tellurium, which limits production levels because tellurium has become increasingly rare. UIUC is replacing this material with microscopic silicon wires that are considerably cheaper and could be equally effective. Improvements in thermoelectric device production could return enough wasted heat to add up to 23% to ourmore » current annual electricity production.« less

The Present, Mid-Term, and Long-Term Supply Curves for Tellurium; and Updates in the Results from NREL's CdTe PV Module Manufacturing Cost Model (Presentation)

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

Woodhouse, M.; Goodrich, A.; Redlinger, M.

2013-09-01

For those PV technologies that rely upon Te, In, and Ga, first-order observations and calculations hint that there may be resource constraints that could inhibit their successful deployment at a SunShot level. These are only first-order approximations, however, and the possibility for an expansion in global Te, In, and Ga supplies needs to be considered in the event that there are upward revisions in their demand and prices.In this study, we examine the current, mid-term, and long-term prospects of Tellurium (Te) for use in PV. We find that the current global supply base of Te would support <10 GW ofmore » annual traditional CdTe PV manufacturing production. But as for the possibility that the supply base for Te might be expanded, after compiling several preliminary cumulative availability curves we find that there may be significant upside potential in the supply base for this element - principally vis a vis increasing demand and higher prices. Primarily by reducing the Tellurium intensity in manufacturing and by increasing the recovery efficiency of Te in Cu refining processes, we calculate that it may prove affordable to PV manufacturers to expand the supply base for Te such that 100 GW, or greater, of annual CdTe PV production is possible in the 2030 - 2050 timeframe.« less

Development of bismuth tellurium selenide nanoparticles for thermoelectric applications via a chemical synthetic process

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

Kim, Cham; Department of Chemical Engineering, Pohang University of Science and Technology; Kim, Dong Hwan

2011-03-15

Research highlights: {yields} We synthesized a Bi{sub 2}Te{sub y}Se{sub 3-y} nano-compound via a chemical synthetic process. {yields} The compound was sintered to achieve an average grain size of about 300 nm. {yields} The resulting sintered body showed very low thermal conductivity. It is likely caused by the vigorous phonon scattering of the nano-sized grains. -- Abstract: Bismuth tellurium selenide (Bi{sub 2}Te{sub y}Se{sub 3-y}) nanoparticles for thermoelectric applications are successfully prepared via a water-based chemical reaction under atmospheric conditions. The nanostructured compound is prepared using a complexing agent (ethylenediaminetetraacetic acid) and a reducing agent (ascorbic acid) to stabilize the bismuth precursormore » (Bi(NO{sub 3}){sub 3}) in water and to favor the reaction with reduced sources of tellurium and selenium. The resulting powder is smaller than ca. 100 nm and has a crystalline structure corresponding to the rhombohedral Bi{sub 2}Te{sub 2.7}Se{sub 0.3}. The nanocrystalline powder is sintered via a spark plasma sintering process to obtain a sintered body composed of nano-sized grains. Important transport properties of the sintered body are measured to calculate its most important characteristic, the thermoelectric performance. The results demonstrate a relationship between the nanostructure of the sintered body and its thermal conductivity.« less

A totally phosphine-free synthesis of metal telluride nanocrystals by employing alkylamides to replace alkylphosphines for preparing highly reactive tellurium precursors.

PubMed

Yao, Dong; Liu, Yi; Zhao, Wujun; Wei, Haotong; Luo, Xintao; Wu, Zhennan; Dong, Chunwei; Zhang, Hao; Yang, Bai

2013-10-21

Despite the developments in the wet chemical synthesis of high-quality semiconductor nanocrystals (NCs) with diverse elemental compositions, telluride NCs are still irreplaceable materials owing to their excellent photovoltaic and thermoelectric performances. Herein we demonstrate the dissolution of elemental tellurium (Te) in a series of alkylamides by sodium borohydride (NaBH4) reduction at relatively low temperature to produce highly reactive precursors for hot-injection synthesis of telluride NCs. The capability to tune the reactivity of Te precursors by selecting injection temperature permits control of NC size over a broad range. The current preparation of Te precursors is simple, economical, and totally phosphine-free, which will promote the commercial synthesis and applications of telluride NCs.

Metalloid compounds as drugs

PubMed Central

Sekhon, B. S.

2013-01-01

The six elements commonly known as metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Metalloid containing compounds have been used as antiprotozoal drugs. Boron-based drugs, the benzoxaboroles have been exploited as potential treatments for neglected tropical diseases. Arsenic has been used as a medicinal agent and arsphenamine was the main drug used to treat syphilis. Arsenic trioxide has been approved for the treatment of acute promyelocytic leukemia. Pentavalent antimonials have been the recommended drug for visceral leishmaniasis and cutaneous leishmaniasis. Tellurium (IV) compounds may have important roles in thiol redox biological activity in the human body, and ammonium trichloro (dioxoethylene-O, O’-)tellurate (AS101) may be a promising agent for the treatment of Parkinson’s disease. Organosilicon compounds have been shown to be effective in vitro multidrug-resistance reverting agents. PMID:24019824

High-power density piezoelectric energy harvesting using radially strained ultrathin trigonal tellurium nanowire assembly.

PubMed

Lee, Tae Il; Lee, Sangmin; Lee, Eungkyu; Sohn, Sungwoo; Lee, Yean; Lee, Sujeong; Moon, Geondae; Kim, Dohyang; Kim, Youn Sang; Myoung, Jae Min; Wang, Zhong Lin

2013-06-04

A high-yield solution-processed ultrathin (<10 nm) trigonal tellurium (t-Te) nanowire (NW) is introduced as a new class of piezoelectric nanomaterial with a six-fold higher piezoelectric constant compared to conventional ZnO NWs for a high-volume power-density nanogenerator (NG). While determining the energy-harvesting principle in a NG consisting of t-Te NW, it is theoretically and experimentally found that t-Te NW is piezoelectrically activated only by creating strain in its radial direction, along which it has an asymmetric crystal structure. Based upon this mechanism, a NG with a monolayer consisting of well-aligned t-Te NWs and a power density of 9 mW/cm(3) is fabricated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tellurium(0) as a ligand: synthesis and characterization of 2-pyridyltellurolates of platinum(II) and structures of [Pt{2-Te-3-(R)C5H3N}2Te(PR'3)] (R = H or Me).

PubMed

Chauhan, Rohit Singh; Kedarnath, G; Wadawale, Amey; Muñoz-Castro, Alvaro; Arratia-Perez, Ramiro; Jain, Vimal K; Kaim, Wolfgang

2010-05-03

Treatment of toluene solutions of the ditellurides [Te(2){C(5)H(3)N(R)-3}(2)] (R = H or Me) with [Pt(PPh(3))(4)] yielded two types of complexes, [Pt{2-Te-3-(R)C(5)H(3)N}(2)(PPh(3))(2)] (1a-d) as the major products and [Pt{2-Te-3-(R)C(5)H(3)N}(2)Te(PPh(3))] (2a-d) as minor products. The above complexes can also be obtained by the reaction of [PtCl(2)(PR'(3))(2)] (PR'(3) = PPh(3) or PPh(2)(2-C(5)H(4)N)) with 2 equiv of Na(2-Te-C(5)H(3)R). The complexes were characterized by elemental analyses and UV-vis, NMR ((1)H and (31)P), and (in part) XPS spectroscopy. The molecular structures of [Pt(2-Te-C(5)H(4)N)(2)Te(PPh(3))] (2a) and [Pt{2-Te-C(5)H(3)(Me)N}(2)Te(PPh(3))] (2b) were established by single crystal X-ray diffraction. Both complexes exhibit a distorted square-planar configuration at the platinum(II) centers. The two mutually trans positioned 2-pyridinetellurolate ligands [2-Te-C(5)H(3)(R)N] coordinate to the central platinum atom in a monodentate fashion through the tellurium atoms. The tellurium(0) atom adopts a "bent T" configuration as it is bridging the 2-Te- C(5)H(3)(R)N molecules via N-Te-N bonds (166 degrees angle) and coordinates to Pt(II) in the trans position to PPh(3). The novel bis(pyridine)tellurium(0) arrangement resembles the bis(pyridine)iodonium structure. The calculated NICS indices and ELF functions clearly show that the compounds 2a and 2b are aromatic in the region defined by the Te-C-N-Te-Pt five-membered rings.

Publications - PIR 2016-2 | Alaska Division of Geological & Geophysical

Science.gov Websites

; Core Drilling; Cretaceous; Geologic Materials Center; Gold; Hayes Glacier Belt; Holocene; Intrusion ; Molybdenum; Placer Gold; Porphyry; Tellurium Top of Page Department of Natural Resources, Division of

Mossbauer studies of bulk and thin-film FeTe

NASA Technical Reports Server (NTRS)

Aggarwal, K.; Escue, W. T.; Mendiratta, R. G.

1978-01-01

In study, dependence of Mossbauer parameters on film thickness and film substrate was measured and related to iron tellurium structure. Report also describes film deposition technique (flash deposition) and Mossbauer apparatus.

Melt-gas phase equilibria and state diagrams of the selenium-tellurium system

NASA Astrophysics Data System (ADS)

Volodin, V. N.; Trebukhov, S. A.; Burabaeva, N. M.; Nitsenko, A. V.

2017-05-01

The partial pressures of saturated vapor of the components in the Se-Te system are determined and presented in the form of temperature-concentration dependences from which the boundaries of the melt-gas phase transition are calculated at atmospheric pressure and vacuums of 2000 and 100 Pa. The existence of azeotropic mixtures is revealed. It is found that the points of inseparably boiling melts correspond to 7.5 at % of Se and 995°C at 101325 Pa, 10.9 at % at 673°C and 19.5 at % at 522°C in vacuums of 2000 and 100 Pa, respectively. A complete state diagram is constructed, including the fields of gas-liquid equilibria at atmospheric and low pressures, the boundaries of which allow us to assess the behavior of selenium and tellurium upon distillation fractionation.

Frequency-resolved optical gating system with a tellurium crystal for characterizing free-electron lasers in the wavelength range of 10-30 {mu}m

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

Iijima, Hokuto; Nagai, Ryoji; Nishimori, Nobuyuki

2009-12-15

A second-harmonic generation frequency-resolved optical gating (SHG-FROG) system has been developed for the complete characterization of laser pulses in the wavelength range of 10-30 {mu}m. A tellurium crystal is used so that spectrally resolved autocorrelation signals with a good signal-to-noise ratio are obtained. Pulses (wavelength {approx}22 {mu}m) generated from a free-electron laser are measured by the SHG-FROG system. The SHG intensity profile and the spectrum obtained by FROG measurements are well consistent with those of independent measurements of the pulse length and spectrum. The pulse duration and spectral width determined from the FROG trace are 0.6 ps and 5.2 THzmore » at full width half maximum, respectively.« less

Comparison of Se and Te clusters produced by ion bombardment

NASA Astrophysics Data System (ADS)

Trzyna, Małgorzata

2017-01-01

Nanostructures based on tellurium and selenium are materials used as components for the manufacturing topological insulators. Therefore it is crucial to precisely characterize these materials. In this work the emission of selenium and tellurium cluster ions, sputtered by Bi+ primary ion guns, was investigated by using Time-of-Flight Secondary Ion Mass Spectrometry (TOF SIMS). It has been found that BixTex and BixSex clusters appear in addition to Sex and Tex clusters in the mass range up to 1300 m/z. Local maxima or minima (magic numbers) are observed in the ion intensity versus a number of atoms per cluster for both positive and negative ions spectra for all types of clusters and primary ions used. These extrema can be attributed to different yield and stability of certain clusters but also to fragmentation of high-mass clusters.

Tellurate enters Escherichia coli K-12 cells via the SulT-type sulfate transporter CysPUWA.

PubMed

Goff, Jennifer; Yee, Nathan

2017-12-29

Soluble forms of tellurium are environmental contaminants that are toxic to microorganisms. While tellurite [Te(IV)] is a well-characterized antimicrobial agent, little is known about the interactions of tellurate [Te(VI)] with bacterial cells. In this study, we investigated the role of sulfate transporters in the uptake of tellurate in Escherichia coli K-12. Mutant strains carrying a deletion of the cysW gene in the CysPUWA sulfate transporter system accumulated less cellular tellurium and exhibited higher resistance to tellurate compared with the wild-type strain. Complementation of the mutation restored tellurate sensitivity and uptake. These results indicate that tellurate enters E. coli cells to cause toxic effects via the CysPUWA sulfate transporter. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Extreme selenium and tellurium contamination in soils--an eighty year-old industrial legacy surrounding a Ni refinery in the Swansea Valley.

PubMed

Perkins, William T

2011-12-15

Elevated levels of selenium (maximum 200 mg/kg) and tellurium (maximum 11 mg/kg) are reported in topsoils (<5 cm) from around a long-established nickel refinery at Clydach in the Lower Swansea Valley, UK. Se and Te are correlated with each other and when these data are plotted as contour diagrams they show a concentric pattern centred on the refinery site. The origin of the Se and Te contamination is investigated. A review of the changes in the refinery practices at the site is presented and used to link the soil contamination to industrial pollution which took place over 80 years ago. The most recent air quality data available cannot rule out some Se contamination up to 2003. Copyright © 2011 Elsevier B.V. All rights reserved.

Some factors affecting efficiencies of n-CdS/p-CdTe thin film solar cells

NASA Astrophysics Data System (ADS)

Morris, G. C.; Das, S. K.; Tanner, P. G.

1992-02-01

Electrodeposited CdS and CdTe thin films have been fabricated into solar cells with a CdS/CdTe heterojunction. The CdTe films were made by varying two parameters, viz. the concentration of tellurium ions in the deposition solution and the quasi-rest potential (QRP) of the deposit. The properties of the completed cells were examined as a function of those preparation variables. Cell efficiency varied with both QRP and tellurium ion concentration. Whilst chemical analytic methods showed no compositional variation between cells, morphological studies showed that the most efficient cells had the largest grain size. Electrical and capacitance measurements were used to show that the density of interband states and of junction interface states increased with structural imperfection. The major losses in the solar cell parameters increased with increased polycrystalline structure.

Improved selectivity for Pb(II) by sulfur, selenium and tellurium analogues of 1,8-anthraquinone-18-crown-5: synthesis, spectroscopy, X-ray crystallography and computational studies.

PubMed

Mariappan, Kadarkaraisamy; Alaparthi, Madhubabu; Hoffman, Mariah; Rama, Myriam Alcantar; Balasubramanian, Vinothini; John, Danielle M; Sykes, Andrew G

2015-07-14

We report here a series of heteroatom-substituted macrocycles containing an anthraquinone moiety as a fluorescent signaling unit and a cyclic polyheteroether chain as the receptor. Sulfur, selenium, and tellurium derivatives of 1,8-anthraquinone-18-crown-5 (1) were synthesized by reacting sodium sulfide (Na2S), sodium selenide (Na2Se) and sodium telluride (Na2Te) with 1,8-bis(2-bromoethylethyleneoxy)anthracene-9,10-dione in a 1 : 1 ratio. The optical properties of the new compounds are examined and the sulfur and selenium analogues produce an intense green emission enhancement upon association with Pb(II) in acetonitrile. Selectivity for Pb(II) is markedly improved as compared to the oxygen analogue 1 which was also competitive for Ca(II) ion. UV-Visible and luminescence titrations reveal that 2 and 3 form 1 : 1 complexes with Pb(II), confirmed by single-crystal X-ray studies where Pb(II) is complexed within the macrocycle through coordinate covalent bonds to neighboring carbonyl, ether and heteroether donor atoms. Cyclic voltammetry of 2-8 showed classical, irreversible oxidation potentials for sulfur, selenium and tellurium heteroethers in addition to two one-electron reductions for the anthraquinone carbonyl groups. DFT calculations were also conducted on 1, 2, 3, 6, 6 + Pb(II) and 6 + Mg(II) to determine the trend in energies of the HOMO and the LUMO levels along the series.

Simultaneous speciation and preconcentration of ultra traces of inorganic tellurium and selenium in environmental samples by hollow fiber liquid phase microextraction prior to electrothermal atomic absorption spectroscopy determination.

PubMed

Ghasemi, Ensieh; Najafi, Nahid Mashkouri; Raofie, Farhad; Ghassempour, Alireza

2010-09-15

A simple and effective speciation and preconcentration method based on hollow fiber liquid phase microextraction (HF-LPME) was developed for simultaneous separation of trace inorganic tellurium and selenium in environmental samples prior to electrothermal atomic absorption spectroscopy (ETAAS) determination. The method involves the selective extraction of the Te (IV) and Se (IV) species by HF-LPME with the use of ammonium pyrrolidinecarbodithioate (APDC) as the chelating agent. The complex compounds were extracted into 10 microL of toluene and the solutions were injected into a graphite furnace for the determination of Te (IV) and Se (IV). To determine the total tellurium and selenium in the samples, first Te (VI) and Se (VI) were reduced to Te (IV) and Se (IV), and then the microextraction method was performed. The experimental parameters of HF-LPME were optimized using a central composite design after a 2(n-1) fractional factorial experimental design. Under optimum conditions, enrichment factors of up to 520 and 480 were achieved for Te (IV) and Se (IV), respectively. The detection limits were 4 ng L(-1) with 3.5% RSD (n=5, c=2.0 microg L(-1)) for Te (IV) and 5 ng L(-1) with 3.1% RSD for Se (IV). The applicability of the developed technique was evaluated by application to spiked, environmental water and soil samples. Copyright 2010 Elsevier B.V. All rights reserved.

Syntheses, crystal structures, and properties of six new lanthanide(III) transition metal tellurium(IV) oxyhalides with three types of structures.

PubMed

Shen, Yue-Ling; Mao, Jiang-Gao

2005-07-25

Solid-state reactions of lanthanide(III) oxide (and lanthanide(III) oxyhalide), transition metal halide (and transition metal oxide), and TeO(2) at high temperature lead to six new lanthanide transition metal tellurium(IV) oxyhalides with three different types of structures, namely, DyCuTe(2)O(6)Cl, ErCuTe(2)O(6)Cl, ErCuTe(2)O(6)Br, Sm(2)Mn(Te(5)O(13))Cl(2), Dy(2)Cu(Te(5)O(13))Br(2), and Nd(4)Cu(TeO(3))(5)Cl(3). Compounds DyCuTe(2)O(6)Cl, ErCuTe(2)O(6)Cl, and ErCuTe(2)O(6)Br are isostructural. The lanthanide(III) ion is eight-coordinated by eight oxygen atoms, and the copper(II) ion is five-coordinated by four oxygens and a halide anion in a distorted square pyramidal geometry. The interconnection of Ln(III) and Cu(II) ions by bridging tellurite anions results in a three-dimensional (3D) network with tunnels along the a-axis; the halide anion and the lone-pair electrons of the tellurium(IV) ions are oriented toward the cavities of the tunnels. Compounds Sm(2)Mn(Te(5)O(13))Cl(2) and Dy(2)Cu(Te(5)O(13))Br(2) are isostructural. The lanthanide(III) ions are eight-coordinated by eight oxygens, and the divalent transition metal ion is octahedrally coordinated by six oxygens. Two types of polymeric tellurium(IV) oxide anions are formed: Te(3)O(8)(4)(-) and Te(4)O(10)(4)(-). The interconnection of the lanthanide(III) and divalent transition metal ions by the above two types of polymeric tellurium(IV) oxide anions leads to a 3D network with long, narrow-shaped tunnels along the b-axis. The halide anions remain isolated and are located at the above tunnels. Nd(4)Cu(TeO(3))(5)Cl(3) features a different structure. All five of the Nd(III) ions are eight-coordinated (NdO(8) for Nd(1), Nd(2), Nd(4), and Nd(5) and NdO(7)Cl for Nd(3)), and the copper(I) ion is tetrahedrally coordinated by four chloride anions. The interconnection of Nd(III) ions by bridging tellurite anions resulted in a 3D network with large tunnels along the b-axis. The CuCl(4) tetrahedra are interconnected into a 1D two-unit repeating (zweier) chain via corner-sharing. These 1D copper(I) chloride chains are inserted into the tunnels of the neodymium(III) tellurite via Nd-Cl-Cu bridges. Luminescent studies show that ErCuTe(2)O(6)Cl and Nd(4)Cu(TeO(3))(5)Cl(3) exhibit strong luminescence in the near-IR region. Magnetic measurements indicate the antiferromagnetic interactions between magnetic centers in these compounds.

Alloys compatibility in molten salt fluorides: Kurchatov Institute related experience

NASA Astrophysics Data System (ADS)

Ignatiev, Victor; Surenkov, Alexandr

2013-10-01

In the last several years, there has been an increased interest in the use of high-temperature molten salt fluorides in nuclear power systems. For all molten salt reactor designs, materials selection is a very important issue. This paper summarizes results, which led to selection of materials for molten salt reactors in Russia. Operating experience with corrosion thermal convection loops has demonstrated good capability of the “nickel-molybdenum alloys + fluoride salt fueled by UF4 and PuF3 + cover gas” system up to 750 °C. A brief description is given of the container material work in progress. Tellurium corrosion of Ni-based alloys in stressed and unloaded conditions studies was also tested in different molten salt mixtures at temperatures up to 700-750 °C, also with measurement of the redox potential. HN80MTY alloy with 1% added Al is the most resistant to tellurium intergranular cracking of Ni-base alloys under study.

Systems and methods for the synthesis of high thermoelectric performance doped-SnTe materials

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

Ren, Zhifeng; Zhang, Qian; Chen, Gang

A thermoelectric composition comprising tin (Sn), tellurium (Te) and at least one dopant that comprises a peak dimensionless figure of merit (ZT) of 1.1 and a Seebeck coefficient of at least 50 .mu.V/K and a method of manufacturing the thermoelectric composition. A plurality of components are disposed in a ball-milling vessel, wherein the plurality of components comprise tin (Sn), tellurium (Te), and at least one dopant such as indium (In). The components are subsequently mechanically and thermally processed, for example, by hot-pressing. In response to the mechanical-thermally processing, a thermoelectric composition is formed, wherein the thermoelectric composition comprises a dimensionlessmore » figure of merit (ZT) of the thermoelectric composition is at least 0.8, and wherein a Seebeck coefficient of the thermoelectric composition is at least 50 .mu.V/K at any temperature.« less

Analysis of tellurium as n-type dopant in GaInP: Doping, diffusion, memory effect and surfactant properties

NASA Astrophysics Data System (ADS)

García, I.; Rey-Stolle, I.; Galiana, B.; Algora, C.

2007-01-01

The use of tellurium as n-type dopant for GaAs and InP has several advantages, including a high incorporation efficiency, the very high doping levels achievable and a low diffusion coefficient. However, its use to dope Ga xIn 1-xP is not straightforward, since it shows several problems like a remarkable memory effect and an acute inertia of the material to become Te-doped, which gives rise to gradual doping profiles. In this paper, all these phenomena are studied and quantified using secondary ion mass spectroscopy (SIMS) and electrochemical CV profiling (ECV) measurements. Concerning the gradual doping profiles, their origin is linked to the interaction of Te and In in the gas phase and on the growth surface. A phenomenological explanation is given for this effect although the exact physical processes behind remain to be defined.

Use of separate ZnTe interface layers to form OHMIC contacts to p-CdTe films

DOEpatents

Gessert, Timothy A.

1999-01-01

A method of improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurim-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact.

Electrochemical Deposition of Lanthanum Telluride Thin Films and Nanowires

NASA Astrophysics Data System (ADS)

Chi, Su (Ike); Farias, Stephen; Cammarata, Robert

2013-03-01

Tellurium alloys are characterized by their high performance thermoelectric properties and recent research has shown nanostructured tellurium alloys display even greater performance than bulk equivalents. Increased thermoelectric efficiency of nanostructured materials have led to significant interests in developing thin film and nanowire structures. Here, we report on the first successful electrodeposition of lanthanum telluride thin films and nanowires. The electrodeposition of lanthanum telluride thin films is performed in ionic liquids at room temperature. The synthesis of nanowires involves electrodepositing lanthanum telluride arrays into anodic aluminum oxide (AAO) nanoporous membranes. These novel procedures can serve as an alternative means of simple, inexpensive and laboratory-environment friendly methods to synthesize nanostructured thermoelectric materials. The thermoelectric properties of thin films and nanowires will be presented to compare to current state-of-the-art thermoelectric materials. The morphologies and chemical compositions of the deposited films and nanowires are characterized using SEM and EDAX analysis.

Stable surface passivation process for compound semiconductors

DOEpatents

Ashby, Carol I. H.

2001-01-01

A passivation process for a previously sulfided, selenided or tellurated III-V compound semiconductor surface. The concentration of undesired mid-gap surface states on a compound semiconductor surface is reduced by the formation of a near-monolayer of metal-(sulfur and/or selenium and/or tellurium)-semiconductor that is effective for long term passivation of the underlying semiconductor surface. Starting with the III-V compound semiconductor surface, any oxidation present thereon is substantially removed and the surface is then treated with sulfur, selenium or tellurium to form a near-monolayer of chalcogen-semiconductor of the surface in an oxygen-free atmosphere. This chalcogenated surface is then contacted with a solution of a metal that will form a low solubility chalcogenide to form a near-monolayer of metal-chalcogen-semiconductor. The resulting passivating layer provides long term protection for the underlying surface at or above the level achieved by a freshly chalcogenated compound semiconductor surface in an oxygen free atmosphere.

Synthesis, structure and imaging of oligodeoxyribonucleotides with tellurium-nucleobase derivatization.

PubMed

Sheng, Jia; Hassan, Abdalla E A; Zhang, Wen; Zhou, Jianfeng; Xu, Bingqian; Soares, Alexei S; Huang, Zhen

2011-05-01

We report here the first synthesis of 5-phenyl-telluride-thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNA duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation. © The Author(s) 2011. Published by Oxford University Press.

Polymerization of tellurophene derivatives via microwave-assisted palladium-catalyzed ipso-arylative polymerization**

PubMed Central

Park, Young S.; Wu, Qin; Nam, Chang-Yong; Grubbs, Robert B.

2014-01-01

We report the synthesis of a tellurophene-containing low bandgap polymer, PDPPTe2T, via microwave-assisted palladium-catalyzed ipso-arylative polymerization of 2,5-bis[(α-hydroxy-α,α-diphenyl)methyl]tellurophene with a diketopyrrolopyrrole (DPP) monomer. Compared with the corresponding thiophene analog, PDPPTe2T absorbs light of longer wavelengths and has a smaller bandgap. Bulk heterojunction solar cells prepared from PDPPTe2T and PC71BM show PCE values of up to 4.4%. External quantum efficiency measurements show that PDPPTe2T produces photocurrent at wavelengths up to 1 μm. DFT calculations suggest that the atomic substitution from sulfur to tellurium increases electronic coupling to decrease the length of the carbon-carbon bonds between the tellurophene and thiophene rings, which results in the red-shift in absorption upon substitution of tellurium for sulfur. PMID:25145499

Synthesis, structure and imaging of oligodeoxyribonucleotides with tellurium-nucleobase derivatization

PubMed Central

Sheng, Jia; Hassan, Abdalla E. A.; Zhang, Wen; Zhou, Jianfeng; Xu, Bingqian; Soares, Alexei S.; Huang, Zhen

2011-01-01

We report here the first synthesis of 5-phenyl–telluride–thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNA duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation. PMID:21245037

Heavily doped GaAs:Te layers grown by MOVPE using diisopropyl telluride as a source

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

Daniltsev, V. M.; Demidov, E. V.; Drozdov, M. N.

2016-11-15

The capabilities of GaAs epitaxial layers extremely heavily doped with tellurium by metal-organic vapor-phase epitaxy using diisopropyl telluride as a source are studied. It is shown that tellurium incorporation into GaAs occurs to an atomic concentration of 10{sup 21} cm{sup –3} without appreciable diffusion and segregation effects. Good carrier concentrations (2 × 10{sup 19} cm{sup –3}) and specific contact resistances of non-alloyed ohmic contacts (1.7 × 10{sup –6} Ω cm{sup 2}) give grounds to use such layers to create non-alloyed ohmic contacts in electronic devices. A sharp decrease in the electrical activity of Te atoms, a decrease in the electronmore » mobility, and an increase in the contact resistance at atomic concentrations above 2 × 10{sup 20} cm{sup –3} are detected.« less

Selenium- and tellurium-containing multifunctional redox agents as biochemical redox modulators with selective cytotoxicity.

PubMed

Jamier, Vincent; Ba, Lalla A; Jacob, Claus

2010-09-24

Various human diseases, including different types of cancer, are associated with a disturbed intracellular redox balance and oxidative stress (OS). The past decade has witnessed the emergence of redox-modulating compounds able to utilize such pre-existing disturbances in the redox state of sick cells for therapeutic advantage. Selenium- and tellurium-based agents turn the oxidizing redox environment present in certain cancer cells into a lethal cocktail of reactive species that push these cells over a critical redox threshold and ultimately kill them through apoptosis. This kind of toxicity is highly selective: normal, healthy cells remain largely unaffected, since changes to their naturally low levels of oxidizing species produce little effect. To further improve selectivity, multifunctional sensor/effector agents are now required that recognize the biochemical signature of OS in target cells. The synthesis of such compounds provides interesting challenges for chemistry in the future.

Synthesis Structure and Imaging of Oligodeoxyribonucleotides with Tellurium-nucleobase Derivatization

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

J Sheng; A Hassan; W Zhang

2011-12-31

We report here the first synthesis of 5-phenyl-telluride-thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNAmore » duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation.« less

Synthesis, structure and imaging of oligodeoxyribonucleotides with tellurium-nucleobase derivatization

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

Sheng, J.; Soares, A.; Hassan, A. E. A.

2011-05-01

We report here the first synthesis of 5-phenyl-telluride-thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNAmore » duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation.« less

Isolation, identification and characterization of highly tellurite-resistant, tellurite-reducing bacteria from Antarctica

NASA Astrophysics Data System (ADS)

Arenas, Felipe A.; Pugin, Benoit; Henríquez, Nicole A.; Arenas-Salinas, Mauricio A.; Díaz-Vásquez, Waldo A.; Pozo, María F.; Muñoz, Claudia M.; Chasteen, Thomas G.; Pérez-Donoso, José M.; Vásquez, Claudio C.

2014-03-01

The tellurium oxyanion, tellurite, is extremely noxious to most living organisms. Its toxicity has been mainly related to the generation of reactive oxygen species (ROS) as well as to an unbalancing of the thiol:redox buffering system. Nevertheless, a few bacteria are capable of thriving at high tellurite concentrations. One mechanism of resistance is the enzymatic and non-enzymatic reduction of tellurite to the less toxic elemental tellurium. This reduction generates nano- to micrometric tellurium crystals that display different shapes and sizes. To date, a very limited number of highly tellurite-resistant and tellurite-reducing bacterial species are available from international culture collections. In this work, we decided to look for tellurite-reducing bacteria from an extreme environment, Antarctica. This environment exhibits a combination of several extreme factors such as high UV-radiation and desiccation and freezing conditions that impact directly on the local biodiversity. Since, as does, all these factors induce ROS formation, we hypothesized that Antarctic bacteria could also exhibit tellurite-resistance. In this context, we isolated 123 tellurite-resistant bacteria, and characterized six new tellurite-resistant and tellurite-reducing bacterial strains from samples collected in Antarctica. These strains were identified according to their 16S rRNA gene sequence as Staphylococcus hameolyticus, Staphylococcus sciuri, Acinetobacter haemolyticus, Pseudomonas lini, and two strains of Psychrobacter immobilis. The isolates display tellurite-resistance about 35- to 500-fold higher than Escherichia coli (Te-sensitive organism), and a high level of tellurite reduction which might be interesting for an application in the field of bioremediation or nanoparticle biosynthesis.

Fundamental Studies on Donor-acceptor Conjugated Polymers Containing 'Heavy' Group 14 and Group 16 Elements

NASA Astrophysics Data System (ADS)

Gibson, Gregory Laird

One advantage of conjugated polymers as organic materials is that their properties may be readily tuned through covalent modifications. This thesis presents studies on the structure-property relationships resulting from single- and double-atom substitutions on an alternating donor-acceptor conjugated polymer. Specifically, single selenium and tellurium atoms have been incorporated into the acceptor monomer in place of sulfur; silicon and germanium atoms have been substituted in place of carbon at the donor monomer bridge position. The carbon-donor/ tellurium-acceptor polymer was synthesized by a post-polymerization reaction sequence and demonstrated the utility of heavy group 16 atoms to red shift a polymer absorption spectrum. Density functional theory calculations point to a new explanation for this result invoking the lower heavy atom ionization energy and reduced aromaticity of acceptor monomers containing selenium and tellurium compared to sulfur. Absorption and emission experiments demonstrate that both silicon and germanium substitutions in the donor slightly blue shift the polymer absorption spectrum. Polymers containing sulfur in the acceptor are the strongest light absorbers of all polymers studied here. Molecular weight and phenyl end capping studies show that molecular weight appears to affect polymer absorption to the greatest degree in a medium molecular weight regime and that these effects have a significant aggregation component. Solar cell devices containing either the silicon- or germanium-donor/selenium-acceptor polymer display improved red light harvesting or hole mobility relative to their structural analogues. Overall, these results clarify the effects of single atom substitution on donor-acceptor polymers and aid in the future design of polymers containing heavy atoms.

Determination of tellurium by hydride generation with in situ trapping flame atomic absorption spectrometry

NASA Astrophysics Data System (ADS)

Matusiewicz, Henryk; Krawczyk, Magdalena

2007-03-01

The analytical performance of coupled hydride generation — integrated atom trap (HG-IAT) atomizer flame atomic absorption spectrometry (FAAS) system was evaluated for determination of Te in reference material (GBW 07302 Stream Sediment), coal fly ash and garlic. Tellurium, using formation of H 2Te vapors, is atomized in air-acetylene flame-heated IAT. A new design HG-IAT-FAAS hyphenated technique that would exceed the operational capabilities of existing arrangements (a water-cooled single silica tube, double-slotted quartz tube or an "integrated trap") was investigated. An improvement in detection limit was achieved compared with using either of the above atom trapping techniques separately. The concentration detection limit, defined as 3 times the blank standard deviation (3 σ), was 0.9 ng mL - 1 for Te. For a 2 min in situ pre-concentration time (sample volume of 2 mL), sensitivity enhancement compared to flame AAS, was 222 fold, using the hydride generation — atom trapping technique. The sensitivity can be further improved by increasing the collection time. The precision, expressed as RSD, was 7.0% ( n = 6) for Te. The designs studied include slotted tube, single silica tube and integrated atom trap-cooled atom traps. The accuracy of the method was verified using a certified reference material (GBW 07302 Stream Sediment) by aqueous standard calibration curves. The measured Te contents of the reference material was in agreement with the information value. The method was successfully applied to the determination of tellurium in coal fly ash and garlic.

Double Beta Decay of Tellurium-130: Current Status

NASA Technical Reports Server (NTRS)

Meshik, A. P.; Hohenberg, C. M.; Pravdivtseva, O. V.; Bernatowicz, T. J.

2002-01-01

Geochemically measured values of Te-130 half-life form two distinct clusters. Two different experiments were performed to check two proposed explanations: Xe loss and Xe inheritance. Neither is observed. Additional information is contained in the original extended abstract.

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

Kathawa, J.; Fry, C.; Thoennessen, M., E-mail: thoennessen@nscl.msu.edu

Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is described here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

77 FR 64311 - Potential Market Impact of the Proposed Fiscal Year 2014 Annual Materials Plan; National Defense...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-19

...,000 (5) Cadmium Zinc Tellurium (CZT) substrates.. cm\\2\\ 24,000 (6) Lithium Cobalt Oxide (LCO) Kg 750 (6) Lithium Nickel Cobalt Aluminum Oxide kg 540 (6) (NCA). Mesocarbon Microbeads (MCMB) kg 648 (6...

Development of tellurium oxide and lead-bismuth oxide glasses for mid-wave infra-red transmission optics

NASA Astrophysics Data System (ADS)

Zhou, Beiming; Rapp, Charles F.; Driver, John K.; Myers, Michael J.; Myers, John D.; Goldstein, Jonathan; Utano, Rich; Gupta, Shantanu

2013-03-01

Heavy metal oxide glasses exhibiting high transmission in the Mid-Wave Infra-Red (MWIR) spectrum are often difficult to manufacture in large sizes with optimized physical and optical properties. In this work, we researched and developed improved tellurium-zinc-barium and lead-bismuth-gallium heavy metal oxide glasses for use in the manufacture of fiber optics, optical components and laser gain materials. Two glass families were investigated, one based upon tellurium and another based on lead-bismuth. Glass compositions were optimized for stability and high transmission in the MWIR. Targeted glass specifications included low hydroxyl concentration, extended MWIR transmission window, and high resistance against devitrification upon heating. Work included the processing of high purity raw materials, melting under controlled dry Redox balanced atmosphere, finning, casting and annealing. Batch melts as large as 4 kilograms were sprue cast into aluminum and stainless steel molds or temperature controlled bronze tube with mechanical bait. Small (100g) test melts were typically processed in-situ in a 5%Au°/95%Pt° crucible. Our group manufactured and evaluated over 100 different experimental heavy metal glass compositions during a two year period. A wide range of glass melting, fining, casting techniques and experimental protocols were employed. MWIR glass applications include remote sensing, directional infrared counter measures, detection of explosives and chemical warfare agents, laser detection tracking and ranging, range gated imaging and spectroscopy. Enhanced long range mid-infrared sensor performance is optimized when operating in the atmospheric windows from ~ 2.0 to 2.4μm, ~ 3.5 to 4.3μm and ~ 4.5 to 5.0μm.

Analysis of secondary cells with lithium anodes and immobilized fused-salt electrolytes

NASA Technical Reports Server (NTRS)

Cairns, E. J.; Rogers, G. L.; Shimotake, H.

1969-01-01

Secondary cells with liquid lithium anodes, liquid bismuth or tellurium cathodes, and fused lithium halide electrolytes immobilized as rigid pastes operate between 380 and 485 degrees. Applications include power sources in space, military vehicle propulsion and special commercial vehicle propulsion.

Manufacturing Methods and Technology. Project Summary Reports

DTIC Science & Technology

1979-06-01

Specification grade Composition C-4 was successfully made in the laboratory using n-octane as the lacquer solvent. A modification of the Wabash method was...lifetime. This is a significant milestone for sealed metal dewar systems for high density mercury- cadmium -tellurium detectors. Such dewars are

Ore Deposits Mined for Critical Elements

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

Verplanck, Philip; Kelley, Karen

Summary of deposit types containing critical elements, including, cobalt, gallium, germanium, indium, niobium, PGE, REE, rhenium, selenium, and tellurium. Includes information about ore deposit type, mineralogy, geologic setting, example deposits and districts, concentration ranges per reported resource, grade, and additional deposit notes. References are also included.

A thermodynamic database for tellurium-bearing systems relevant to nuclear technology

NASA Astrophysics Data System (ADS)

Chattopadhyay, G.; Juneja, J. M.

1993-06-01

A thermodynamic database for tellurium-bearing condensed phases and gaseous species which are relevant to nuclear technology is presented. It contains phase diagrams of the binary systems, PdTe, RhTe, PuTe, SmTe, CsTe, ZrTe, of the ternary systems, ZrTeO, MoTeO, AgTeO, UTeO, CsTeO, BaTeO as well as thermodynamic data for crystalline and liquid Te, for the solid phases Cs 2Te, Ag 2Te, SnTe, BaTe, CeTe, SmTe, RuTe 2, ZrTe 2, Fe 0.53Te 0.47, Mo 0.43Te 0.57, Cr 0.43Te 0.57, Ni 0.5Te 0.4, Cs 2TeO 3 and for the gaseous species, Te, Te 2, TeO, TeO 2, TeO(OH) 2, H 2Te, TeI, TeI 2, TeI 4, TeOI 2, SnTe, Sn 2Te 2, SnTe 2.

Ultrathin inorganic molecular nanowire based on polyoxometalates

PubMed Central

Zhang, Zhenxin; Murayama, Toru; Sadakane, Masahiro; Ariga, Hiroko; Yasuda, Nobuhiro; Sakaguchi, Norihito; Asakura, Kiyotaka; Ueda, Wataru

2015-01-01

The development of metal oxide-based molecular wires is important for fundamental research and potential practical applications. However, examples of these materials are rare. Here we report an all-inorganic transition metal oxide molecular wire prepared by disassembly of larger crystals. The wires are comprised of molybdenum(VI) with either tellurium(IV) or selenium(IV): {(NH4)2[XMo6O21]}n (X=tellurium(IV) or selenium(IV)). The ultrathin molecular nanowires with widths of 1.2 nm grow to micrometre-scale crystals and are characterized by single-crystal X-ray analysis, Rietveld analysis, scanning electron microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible spectroscopy, thermal analysis and elemental analysis. The crystals can be disassembled into individual molecular wires through cation exchange and subsequent ultrasound treatment, as visualized by atomic force microscopy and transmission electron microscopy. The ultrathin molecular wire-based material exhibits high activity as an acid catalyst, and the band gap of the molecular wire-based crystal is tunable by heat treatment. PMID:26139011

Structural and optical properties of electron-beam-evaporated ZnSe 1- x Te x Ternary compounds with various Te contents

NASA Astrophysics Data System (ADS)

Suthagar, J.; Suthan Kissinger, N. J.; Sharli Nath, G. M.; Perumal, K.

2014-01-01

ZnSe1- x Te x films with different tellurium (Te) contents were deposited by using an electron beam (EB) evaporation technique onto glass substrates for applications to optoelectronic devices. The structural and the optical properties of the ZnSe1- x Te x films were studied in the present work. The host material ZnSe1- x Te x , were prepared by using the physical vapor deposition method of the electron beam evaporation technique (PVD: EBE) under a pressure of 1 × 10-5 mbar. The X-ray diffractogram indicated that these alloy films had cubic structure with a strong preferential orientation of the crystallites along the (1 1 1) direction. The optical properties showed that the band gap (E g ) values varied from 2.73 to 2.41 eV as the tellurium content varied from 0.2 to 0.8. Thus the material properties can be altered and excellently controlled by controlling the system composition x.

Resource recovery from urban stock, the example of cadmium and tellurium from thin film module recycling.

PubMed

Simon, F-G; Holm, O; Berger, W

2013-04-01

Raw material supply is essential for all industrial activities. The use of secondary raw material gains more importance since ore grade in primary production is decreasing. Meanwhile urban stock contains considerable amounts of various elements. Photovoltaic (PV) generating systems are part of the urban stock and recycling technologies for PV thin film modules with CdTe as semiconductor are needed because cadmium could cause hazardous environmental impact and tellurium is a scarce element where future supply might be constrained. The paper describes a sequence of mechanical processing techniques for end-of-life PV thin film modules consisting of sandblasting and flotation. Separation of the semiconductor material from the glass surface was possible, however, enrichment and yield of valuables in the flotation step were non-satisfying. Nevertheless, recovery of valuable metals from urban stock is a viable method for the extension of the availability of limited natural resources. Copyright © 2013 Elsevier Ltd. All rights reserved.

Electrical properties of Pb{sub 1-x}Mn{sub x}Te single crystals with an excess of tellurium

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

Bagieva, G. Z., E-mail: bagieva-gjulandam@rambler.ru; Abdinova, G. D.; Mustafayev, N. B.

2013-03-15

The effect of excess Te atoms (as high as 0.5 at %) and thermal treatment at 473 K for 120 h on the electrical conductivity {sigma}, the thermopower coefficient {alpha}, and the Hall coefficient R of Pb{sub 0.96}Mn{sub 0.04}Te single crystals in the temperature range {approx}77-300 K is investigated. It is shown that excess atoms of tellurium predominantly act as acceptor impurity centers at low concentrations in unannealed samples and form antisite defects at relatively high concentrations (0.05 at % or higher) being located mainly in vacancies of the lead sublattice, and decrease the hole concentration. As a result ofmore » annealing, certain lattice defects (for example, deformational) are healed, and the accommodation process for Te atoms at lead-sublattice vacancies is intensified. These processes substantially affect the values of the electrical parameters, their temperature dependences, as well as the sign of the thermopower and Hall coefficients of the samples.« less

Defect chemistry and characterization Hg(1-x)Cd(x)Te

NASA Technical Reports Server (NTRS)

Vydyanath, H. R.; Donovan, J. C.

1981-01-01

Iodine doped single crystal samples of mercury cadmium telluride were annealed at temperatures varying from 450 C to 600 C in Hg vapor and quenched to room temperature. Hall effect measurements at 77 K on the crystals cooled to room temperature indicate the samples to be n-type after anneals at high Hg pressures whereas they turn p-type after anneals at low Hg pressures; the electron concentration increases with increase in Hg pressure. The results are explained on the basis that the crystals are saturated with (Hg,Cd)I2, with a fraction of the iodine being present as donor occupying tellurium lattice sites and a fraction being present as acceptors resulting from the iodine on tellurium lattice sites pairing with the doubly ionized native acceptor defects. The solubility of the donor species increases with increase in Hg pressure, whereas that of the acceptor species increases with decrease in Hg pressure. Equilibrium constants for the incorporation of the iodine species as well as the pairing reaction were established.

The Effect of Twin Boundaries on the Spectroscopic Performance of CdZnTe Detectors

NASA Technical Reports Server (NTRS)

Parker, Bradford H.; Stahle, C. M.; Roth, D.; Babu, S.; Tueller, Jack; Powers, Edward I. (Technical Monitor)

2001-01-01

Most single grains in cadmium zinc telluride (CdZnTe) grown by the high-pressure Bridgman (HPB) technique contain multiple twin boundaries. As a consequence, twin boundaries are one of the most common macroscopic material defects found in large area (400 to 700 sq mm) CdZnTe specimens obtained from HPB ingots. Due to the prevalence of twin boundaries, understanding their effect on detector performance is key to the material selection process. Twin boundaries in several 2 mm thick large area specimens were first, documented using infrared transmission imaging. These specimens were then fabricated into either 2 mm pixel or planar detectors in order to examine the effect of the twin boundaries on detector performance. Preliminary results show that twin boundaries, which are decorated with tellurium inclusions, produce a reduction in detector efficiency and a degradation in resolution. The extent of the degradation appears to be a function of the density of tellurium inclusions.

Calculation of 125Te NMR Chemical Shifts at the Full Four-Component Relativistic Level with Taking into Account Solvent and Vibrational Corrections: A Gateway to Better Agreement with Experiment.

PubMed

Rusakova, Irina L; Rusakov, Yuriy Yu; Krivdin, Leonid B

2017-06-29

Four-component relativistic calculations of 125 Te NMR chemical shifts were performed in the series of 13 organotellurium compounds, potential precursors of the biologically active species, at the density functional theory level under the nonrelativistic and four-component fully relativistic conditions using locally dense basis set scheme derived from relativistic Dyall's basis sets. The relativistic effects in tellurium chemical shifts were found to be of as much as 20-25% of the total calculated values. The vibrational and solvent corrections to 125 Te NMR chemical shifts are about, accordingly, 6 and 8% of their total values. The PBE0 exchange-correlation functional turned out to give the best agreement of calculated tellurium shifts with their experimental values giving the mean absolute percentage error of 4% in the range of ∼1000 ppm, provided all corrections are taken into account.

Surface Reactivity Enhancement on a Pd/Bi2Te3 Heterostructure through Robust Topological Surface States

PubMed Central

He, Qing Lin; Lai, Ying Hoi; Lu, Yao; Law, Kam Tuen; Sou, Iam Keong

2013-01-01

We present a study of the surface reactivity of a Pd/Bi2Te3 thin film heterostructure. The topological surface states from Bi2Te3, being delocalized and robust owing to their topological natures, were found to act as an effective electron bath that significantly enhances the surface reactivity of palladium in the presence of two oxidizing agents, oxygen and tellurium respectively, which is consistent with a theoretical calculation. The surface reactivity of the adsorbed tellurium on this heterostructure is also intensified possibly benefitted from the effective transfer of the bath electrons. A partially inserted iron ferromagnetic layer at the interface of this heterostructure was found to play two competing roles arising from the higher-lying d-band center of the Pd/Fe bilayer and the interaction between the ferromagnetism and the surface spin texture of Bi2Te3 on the surface reactivity and their characteristics also demonstrate that the electron bath effect is long-lasting against accumulated thickness of adsorbates. PMID:23970163

Celebrating Two Centuries of Research in Selenium Chemistry: State of the Art and New Prospective.

PubMed

Santi, Claudio; Bagnoli, Luana

2017-12-02

In 2017, the 200th anniversary of the discovery of selenium was celebrated. In 1817, the Swedish chemists, Berzelius and Gahn, on roasting 200 kg of sulfur from a pyrite from the Falun mine, obtained about 3 g of a precipitate that they first wrongly identified as tellurium. Berzelius doubted this result and repeated the analysis some months later realizing that a new element was in his hands and he named this element Selenium (Greek: Selene, moon) in consideration of its resemblance to Tellurium (Latin: Tellus, earth). Several events were organized in the year for this special celebration and this Special Issue would like to be an additional contribution to the success of a research that, especially during the last decades, rapidly grew in different fields: synthesis, medicinal chemistry, biology, material, and environment. These studies are strongly characterized by multi- and interdisciplinary connections, and, for this reason, we collected here contributions coming from different areas and disciplines, not exclusively synthetic organic chemistry.

Determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer quantum dots via spectral analysis of optical signature of the Aharanov-Bohm excitons

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

Ji, Haojie; Dhomkar, Siddharth; Roy, Bidisha

2014-10-28

For submonolayer quantum dot (QD) based photonic devices, size and density of QDs are critical parameters, the probing of which requires indirect methods. We report the determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer QDs, based on spectral analysis of the optical signature of Aharanov-Bohm (AB) excitons, complemented by photoluminescence studies, secondary-ion mass spectroscopy, and numerical calculations. Numerical calculations are employed to determine the AB transition magnetic field as a function of the type-II QD radius. The study of four samples grown with different tellurium fluxes shows that the lateral size of QDs increases by just 50%, evenmore » though tellurium concentration increases 25-fold. Detailed spectral analysis of the emission of the AB exciton shows that the QD radii take on only certain values due to vertical correlation and the stacked nature of the QDs.« less

An economical method for the continuous production of iodine-123

NASA Technical Reports Server (NTRS)

Blue, J. W.; Smith, W. R.; Sodd, V. J.

1968-01-01

Simple and inexpensive method produces iodine 123, in a conventional cyclotron. Tellurium 122, a stable isotope available in enrichments exceeding 95 percent, is held on a porous metal plate by a flowing stream of helium and bombarded with either alpha particles or helium 3.

ThP05 Biogeneration of Volatile Selenium Compounds in Biosolids/Biofuels and Quantification by VD/GC/ICPMS

EPA Science Inventory

A noval analytical approach that uses VD/GC/ICPMS for the on-line extraction and quantificationof volatile organopmetalloids is described. Several species of arsenic, selenium, antimony, bismuth and tellurium are amenable to this technique. Preliminary results of a study on the...

Countering China’s Dominance in the Rare Earth Element Market System

DTIC Science & Technology

2012-02-02

critical materials such as cadmium , tellurium, and helium, which will be required to maintain energy, economic, and defense material independence in...Defense Applications,‖ Paper presented at the 40th Forum on the Geology of Industrial Minerals, Bloomington, Indiana , May 2, 2004, 1. http

Composites comprising biologically-synthesized nanomaterials

DOEpatents

Curran, Seamus; Dias, Sampath; Blau, Werner; Wang, Jun; Oremland, Ronald S; Baesman, Shaun

2013-04-30

The present disclosure describes composite materials containing a polymer material and a nanoscale material dispersed in the polymer material. The nanoscale materials may be biologically synthesized, such as tellurium nanorods synthesized by Bacillus selenitireducens. Composite materials of the present disclosure may have optical limiting properties and find use in optical limiting devices.

Characterizing Semiconductor Alloys for Infrared Sensors

NASA Technical Reports Server (NTRS)

Lehoczky, B. S. L.; Szofran, F. R.; Martin, B. G.

1986-01-01

Report presents results of continuing program aimed at characterizing mercury/cadmium/tellurium alloys and eventually developing improved methods of preparing alloys for use as infrared sensors. Work covered by report includes series of differential thermal analysis (DTA) measurements of alloy compositions with x varied from 9 to 1 in 0.1 increments.

Alterations in antioxidant/oxidant gene expression and proteins following treatment of transformed and normal colon cells with tellurium compounds.

PubMed

Vij, Puneet; Hardej, Diane

2016-04-01

The current study evaluated the potential of TeCl4 and DPDT to accumulate within cells and cause oxidative stress. HO-1, antioxidant gene expression and protein alterations were studied. Copyright © 2016 Elsevier B.V. All rights reserved.

Optical characterization of wide-gap detector-grade semiconductors

NASA Astrophysics Data System (ADS)

Elshazly, Ezzat S.

Wide bandgap semiconductors are being widely investigated because they have the potential to satisfy the stringent material requirements of high resolution, room temperature gamma-ray spectrometers. In particular, Cadmium Zinc Telluride (Cd1-xZnxTe, x˜0.1) and Thallium Bromide (TlBr), due to their combination of high resistivity, high atomic number and good electron mobility, have became very promising candidates for use in X- and gamma-ray detectors operating at room temperature. In this study, carrier trapping times were measured in CZT and TlBr as a function of temperature and material quality. Carrier lifetimes and tellurium inclusion densities were measured in detector-grade Cadmium Zinc Telluride (CZT) crystals grown by the High Pressure Bridgman method and Modified Bridgman method. Excess carriers were produced in the material using a pulsed YAG laser with a 1064nm wavelength and 7ns pulse width. Infrared microscopy was used to measure the tellurium defect densities in CZT crystals. The electronic decay was optically measured at room temperature. Spatial mapping of lifetimes and defect densities in CZT was performed to determine the relationship between defect density and electronic decay. A significant and strong correlation was found between the volume fraction of tellurium inclusions and the carrier trapping time. Carrier trapping times and tellurium inclusions were measured in CZT in the temperature range from 300K to 110K and the results were analyzed using a theoretical trapping model. Spatial mapping of carrier trapping times and defect densities in CZT was performed to determine the relationship between defect density and electronic decay. While a strong correlation between trapping time and defect density of tellurium inclusions was observed, there was no significant change in the trap energy. Carrier trapping times were measured in detector grade thallium bromide (TlBr) and compared with the results for cadmium zinc telluride (CZT) in a temperature range from 300K to 110K. The experimental data was analyzed using a trapping model. In CZT, because the majority carrier concentration is close to the intrinsic carrier concentration, the trapping time increases exponentially as the temperature decreases below about 160K. While, in TlBr, the majority carrier concentration is many orders of magnitude greater than the intrinsic carrier concentration and the trapping time followed a 1T temperature dependence over the range of temperatures studied. The results of the model suggest that a moderately deep compensation center, located approximately 200 meV from the middle of the bandgap, could be used to significantly increase the room temperature trapping time in TlBr. The results of this model demonstrate that the room temperature trapping time in TlBr can, in principle, approach 0.1ms through the introduction of a moderately deep compensation level but without decreasing the overall trap concentration. This strategy is not possible in CZT, because the band gap is too small to use a moderately deep compensation level while still maintaining high material resistivity. Carrier trapping times were measured in three polycrystalline TlBr samples produced by melting commercial TlBr beads in a sealed quartz ampoule for two hours at three different temperatures near the melting point. The trapping time decreased with increasing melting temperature, presumably due to the thermal generation of a trap state.

Selenium and tellurium nanomaterials

NASA Astrophysics Data System (ADS)

Piacenza, Elena; Presentato, Alessandro; Zonaro, Emanuele; Lampis, Silvia; Vallini, Giovanni; Turner, Raymond J.

2018-04-01

Over the last 40 years, the rapid and exponential growth of nanotechnology led to the development of various synthesis methodologies to generate nanomaterials different in size, shape and composition to be applied in various fields. In particular, nanostructures composed of Selenium (Se) or Tellurium (Te) have attracted increasing interest, due to their intermediate nature between metallic and non-metallic elements, being defined as metalloids. Indeed, this key shared feature of Se and Te allows us the use of their compounds in a variety of applications fields, such as for manufacturing photocells, photographic exposure meters, piezoelectric devices, and thermoelectric materials, to name a few. Considering also that the chemical-physical properties of elements result to be much more emphasized when they are assembled at the nanoscale range, huge efforts have been made to develop highly effective synthesis methods to generate Se- or Te-nanomaterials. In this context, the present book chapter will explore the most used chemical and/or physical methods exploited to generate different morphologies of metalloid-nanostructures, focusing also the attention on the major advantages, drawbacks as well as the safety related to these synthetic procedures.

Improving the machinability of leaded free cutting steel through process optimization

NASA Astrophysics Data System (ADS)

Sathyamurthy, P.; Vetrivelmurugan, R.; Sooryaprakash, J.

2018-02-01

Free cutting steel grades are high sulphur grades which can be classified under two categories as Leaded and Non-Leaded. These grades are used for manufacturing components like Nuts, bolts, studs, hydraulic fittings, brake pistons where higher machining is required to get intricate shape. Machinability of these grades are affected by hard oxide inclusions and highly deformed manganese sulphide inclusions. At JSW, machinability of leaded free cutting steel is improved by various process modifications namely deoxidation through carbon and manganese, Tellurium (Rare earth element) addition and maintaining the oxygen level at 80- 120ppm. Former one avoids the formation of hard SiO2 and Al2O3 compounds, Tellurium addition forms PbTe compound at the tail of MnS inclusions which resists the deformation of MnS inclusions and increased oxygen level favours the formation of less deformable oxy- sulphide inclusions. Above process modifications have resulted in achieving the low silicate content, better aspect ratio of MnS inclusions in the final rolled product. They are assessed by the characteristics of chip formation and surface roughness of machined part.

Judd-Ofelt analysis and spectral properties of Dy3+ ions doped niobium containing tellurium calcium zinc borate glasses

NASA Astrophysics Data System (ADS)

Ravi, O.; Reddy, C. Madhukar; Reddy, B. Sudhakar; Deva Prasad Raju, B.

2014-02-01

Niobium containing tellurium calcium zinc borate (TCZNB) glasses doped with different concentrations of Dy3+ ions were prepared by the melt quenching method and their optical properties have been studied. The Judd-Ofelt (J-O) intensity parameters Ωt (t=2, 4 and 6) were calculated using the least square fit method. Based on the magnitude of Ω2 parameter the hypersensitivity of 6H15/2→6F11/2 has also been discussed. From the evaluated J-O intensity parameters as well as from the emission and lifetime measurements, radiative transition properties such as radiative transition probability rates and branching ratios were calculated for 4F9/2 excited level. It is found that for Dy3+ ion, the transition 4F9/2→6H13/2 shows highest emission cross-section at 1.0 mol% TCZNB glass matrix. From the visible luminescence spectra, yellow to blue (Y/B) intensity ratios and chromaticity color coordinates were also estimated. The TCZNB glasses exhibit good luminescence properties and are suitable for generation of white light.

Strain tuning of electronic properties of various dimension elemental tellurium with broken screw symmetry

NASA Astrophysics Data System (ADS)

Xue, Xiong-Xiong; Feng, Ye-Xin; Liao, Lei; Chen, Qin-Jun; Wang, Dan; Tang, Li-Ming; Chen, Keqiu

2018-03-01

We present a systematical study of atomic structures and electronic properties of various dimension tellurium (Te) with broken intrinsical screw symmetry by applying reasonable strain. It is demonstrated that (i) bulk trigonal Te has degenerate Weyl nodes around the H point near the Fermi energy, and this degeneracy will be broken by introducing the selenium (Se) atom through creating the inner unsymmetrical strain, instead of external shear strain. (ii) 2D structures of tetragonal Te (t-Te) and 1T-MoS2-like Te (1T-Te) show direct and indirect band gap, respectively. Under the uniform biaxial compressive (BC) strain, monolayer of t-Te shows the direct-to-indirect band gap transition, while 1T-Te monolayer has a band gap transition firstly from indirect to direct and then from direct to indirect. Their effective masses of hole and electron can be effectively tuned by BC strain. (iii) One-dimensional (1D) structures of single helix, triangular Te and hexagonal Te nanowires display the obvious quantum confinement effect on the band structure and different sensitivity to the effect of uniaxial compressive strain.

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

Clark, Richard A.; McNamara, Bruce K.; Barinaga, Charles J.

The first electron ionization mass spectrum of tellurium hexafluoride (TeF6) is reported. The starting material was produced by direct fluorination of Te metal or TeO2 with nitrogen trifluoride. Formation of TeF6 was confirmed through cryogenic capture of the tellurium fluorination product and analysis through Raman spectroscopy. The eight natural abundance isotopes were observed for each of the set of fragment ions: TeF5+, TeF4+ TeF3+, TeF2+, TeF1+, and Te+, Te2+. A trend in increasing abundance was observed for the even fluoride bearing ions: TeF1+ < TeF3+ < TeF5+, and a decreasing abundance was observed for the even fragment series: Te(0)+ >more » TeF2+ > TeF4+ > TeF6+, with the molecular ion TeF6+ not observed at all. Density functional theory based electronic structure calculations were used to calculate optimized ground state geometries of these gas phase species and their relative stabilities explain the trends in the data and the lack of observed signal for TeF6+.« less

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

Wang, Ying; Qi, Long; Wu, Yihong, E-mail: elewuyh@nus.edu.sg

Few-layer MoS{sub 2} field-effect transistors often show an n-type conduction behavior due to the presence of high-density sulfur vacancies. Here, we investigated the possibility of surface defect passivation of MoS{sub 2} by sulfur treatment in (NH{sub 4}){sub 2}S solution or coating with an ultrathin layer of selenium or tellurium. It was found that all three elements investigated are able to induce a p-doping effect through suppressing the residual electron concentration by an amount exceeding 0.5 × 10{sup 12 }cm{sup −2} in few-layer MoS{sub 2}. Among them, the sulfur-treatment exhibits the most superior thermal stability that survives thermal annealing at temperatures ≥120 °C for atmore » least 10 h. Tellurium exhibits the strongest p-doping effect due to electron trapping by physisorption-induced gap states near the valence band edge. On the other hand, selenium is highly volatile on MoS{sub 2}; it evaporates and desorbs easily due to Joule heating during electrical measurements in vacuum. The results of first-principles calculations support the experimental observations.« less

Characterizing Thermal Properties of Melting Te Semiconductor: Thermal Diffusivity Measurements and Simulation

NASA Technical Reports Server (NTRS)

Zhu, Shen; Li, C.; Su, Ching-Hua; Lin, B.; Ben, H.; Scripa, R. N.; Lehoczky, S. L.; Curreri, Peter A. (Technical Monitor)

2002-01-01

Tellurium is an element for many II-VI and I-III-VI(sub 2) compounds that are useful materials for fabricating many devices. In the melt growth techniques, the thermal properties of the molten phase are important parameter for controlling growth process to improve semiconducting crystal quality. In this study, thermal diffusivity of molten tellurium has been measured by a laser flash method in the temperature range from 500 C to 900 C. A pulsed laser with 1064 nm wavelength is focused on one side of the measured sample. The thermal diffusivity can be estimated from the temperature transient at the other side of the sample. A numerical simulation based on the thermal transport process has been also performed. By numerically fitting the experimental results, both the thermal conductivity and heat capacity can be derived. A relaxation phenomenon, which shows a slow drift of the measured thermal conductivity toward the equilibrium value after cooling of the sample, was observed for the first time. The error analysis and the comparison of the results to published data measured by other techniques will be discussed.

Characterizing Thermal Properties of Melting Te Semiconductor: Thermal Diffusivity Measurements and Simulation

NASA Technical Reports Server (NTRS)

Zhu, Shen; Su, Ching-Hua; Li, C.; Lin, B.; Ben, H.; Scripa, R. N.; Lehoczky, S. L.; Curreri, Peter A. (Technical Monitor)

2002-01-01

Tellurium is an element for many II-VI and I-III-VI(sub 2) compounds that are useful materials for fabricating many devises. In the melt growth techniques, the thermal properties of the molten phase are important parameter for controlling growth process to improve semiconducting crystal quality. In this study, thermal diffusivity of molten tellurium has been measured by a laser flash method in the temperature range from 500 C to 900 C. A pulsed laser with 1064 nm wavelength is focused on one side of the measured sample. The thermal diffusivity can be estimated from the temperature transient at the other side of the sample. A numerical simulation based on the thermal transport process has been also performed. By numerically fitting the experimental results, both the thermal conductivity and heat capacity can be derived. A relaxation phenomenon, which shows a slow drift of the measured thermal conductivity toward the equilibrium value after cooling of the sample, was observed for the first time. The error analysis and the comparison of the results to published data measured by other techniques will be discussed in the presentation.

Direct and Selective Synthesis of Hydrogen Peroxide over Palladium-Tellurium Catalysts at Ambient Pressure.

PubMed

Tian, Pengfei; Xu, Xingyan; Ao, Can; Ding, Doudou; Li, Wei; Si, Rui; Tu, Weifeng; Xu, Jing; Han, Yi-Fan

2017-09-11

Highly selective hydrogen peroxide (H 2 O 2 ) synthesis directly from H 2 and O 2 is a strongly desired reaction for green processes. Herein a highly efficient palladium-tellurium (Pd-Te/TiO 2 ) catalyst with a selectivity of nearly 100 % toward H 2 O 2 under mild conditions (283 K, 0.1 MPa, and a semi-batch continuous flow reactor) is reported. The size of Pd particles was remarkably reduced from 2.1 nm to 1.4 nm with the addition of Te. The Te-modified Pd surface could significantly weaken the dissociative activation of O 2 , leading to the non-dissociative hydrogenation of O 2 . Density functional theory calculations illuminated the critical role of Te in the selective hydrogenation of O 2 , in that the active sites composed of Pd and Te could significantly restrain side reactions. This work has made significant progress on the development of high-selectivity catalysts for the direct synthesis of H 2 O 2 at ambient pressure. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Theoretical studies of the electronic spectrum of tellurium monosulfide.

PubMed

Chattopadhyaya, Surya; Nath, Abhijit; Das, Kalyan Kumar

2013-08-01

Ab initio based multireference singles and doubles configuration interaction (MRDCI) study including spin-orbit coupling is carried out to explore the electronic structure and spectroscopic properties of tellurium monosulfide (TeS) molecule by employing relativistic effective core potentials (RECP) and suitable Gaussian basis sets of the constituent atoms. Potential energy curves correlating with the lowest and second dissociation limit are constructed and spectroscopic constants (T(e), r(e), and ω(e)) of several low-lying bound Λ-S electronic states up to 3.68 eV of energy are computed. The binding energies and electric dipole moments (μ(e)) of the ground and the low-lying excited Λ-S states are also computed. The effects of the spin-orbit coupling on the electronic spectrum of the species are studied in details and compared with the available data. The transition probabilities of some dipole-allowed and spin-forbidden transitions are computed and radiative lifetimes of some excited states at lowest vibrational level are estimated from the transition probability data. Copyright © 2013 Elsevier B.V. All rights reserved.

Sublimation-Condensation of Multiscale Tellurium Structures

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

Riley, Brian J.; Johnson, Bradley R.; Schaef, Herbert T.

This paper presents a simple technique for making tellurium (Te) nano and microtubes of widely varying dimensions with Multi-Scale Processing (MSP). In this process, the Te metal is placed in a reaction vessel (e.g., borosilicate or fused quartz), the vessel is evacuated, and then sealed under vacuum with a torch. The vessel is heat-treated in a temperature gradient where a portion of the tube that can also contain an additional substrate, is under a decreasing temperature gradient. Scanning and transmission electron microscopies have shown that multifaceted crystalline tubes have been formed extending from nano- up to micron-scale with diameters rangingmore » from 51.2 ± 5.9 to 1042 ± 134 nm between temperatures of 157 and 224 °C, respectively. One-dimensional tubular features are seen at lower temperatures, while three-dimensional features, at the higher temperatures. These features have been characterized with X-ray diffraction and found to be trigonal Te with space group P3121. Our results show that the MSP can adequately be described using a simple Arrhenius equation.« less

Biogenic tellurium nanorods as a novel antivirulence agent inhibiting pyoverdine production in Pseudomonas aeruginosa.

PubMed

Mohanty, Anee; Kathawala, Mustafa Hussain; Zhang, Jianhua; Chen, Wei Ning; Loo, Joachim Say Chye; Kjelleberg, Staffan; Yang, Liang; Cao, Bin

2014-05-01

While antibiotic resistance in bacteria is rapidly increasing, the development of new antibiotics has decreased in recent years. Antivirulence drugs disarming rather than killing pathogens have been proposed to alleviate the problem of resistance inherent to existing biocidal antibiotics. Here, we report a nontoxic biogenic nanomaterial as a novel antivirulence agent to combat bacterial infections caused by Pseudomonas aeruginosa. We synthesized, in an environmentally benign fashion, tellurium nanorods (TeNRs) using the metal-reducing bacterium Shewanella oneidensis, and found that the biogenic TeNRs could effectively inhibit the production of pyoverdine, one of the most important virulence factors in P. aeruginosa. Our results suggest that amyloids and extracellular polysaccharides Pel and Psl are not involved in the interactions between P. aeruginosa and the biogenic TeNRs, while flagellar movement plays an important role in the cell-TeNRs interaction. We further showed that the TeNRs (up to 100 µg/mL) did not exhibit cytotoxicity to human bronchial epithelial cells and murine macrophages. Thus, biogenic TeNRs hold promise as a novel antivirulence agent against P. aeruginosa. © 2013 Wiley Periodicals, Inc.

From elemental tellurium to Ge2Sb2Te5 melts: High temperature dynamic and relaxation properties in relationship with the possible fragile to strong transition

NASA Astrophysics Data System (ADS)

Flores-Ruiz, H.; Micoulaut, M.

2018-01-01

We investigate the dynamic properties of Ge-Sb-Te phase change melts using first principles molecular dynamics with a special emphasis on the effect of tellurium composition on melt dynamics. From structural models and trajectories established previously [H. Flores-Ruiz et al., Phys. Rev. B 92, 134205 (2015)], we calculate the diffusion coefficients for the different species, the activation energies for diffusion, the Van Hove correlation, and the intermediate scattering functions able to substantiate the dynamics and relaxation behavior of the liquids as a function of temperature and composition that is also compared to experiment whenever possible. We find that the diffusion is mostly Arrhenius-like and that the addition of Ge/Sb atoms leads to a global decrease of the jump probability and to an increase in activated dynamics for diffusion. Relaxation behavior is analyzed and used in order to evaluate the possibility of a fragile to strong transition that is evidenced from the calculated high fragility (M = 129) of Ge2Sb2Te5 at high temperatures.

Potential for improved extraction of tellurium as a byproduct of current copper mining processes

NASA Astrophysics Data System (ADS)

Hayes, S. M.; Spaleta, K. J.; Skidmore, A. E.

2016-12-01

Tellurium (Te) is classified as a critical element due to its increasing use in high technology applications, low average crustal abundance (3 μg kg-1), and primary source as a byproduct of copper extraction. Although Te can be readily recovered from copper processing, previous studies have estimated a 4 percent extraction efficiency, and few studies have addressed Te behavior during the entire copper extraction process. The goals of the present study are to perform a mass balance examining Te behavior during copper extraction and to connect these observations with mineralogy of Te-bearing phases which are essential first steps in devising ways to optimize Te recovery. Our preliminary mass balance results indicate that less than 3 percent of Te present in copper ore is recovered, with particularly high losses during initial concentration of copper ore minerals by flotation. Tellurium is present in the ore in telluride minerals (e.g., Bi-Te-S phases, altaite, and Ag-S-Se-Te phases identified using electron microprobe) with limited substitution into sulfide minerals (possibly 10 mg kg-1 Te in bulk pyrite and chalcopyrite). This work has also identified Te accumulation in solid-phase intermediate extraction products that could be further processed to recover Te, including smelter dusts (158 mg kg-1) and pressed anode slimes (2.7 percent by mass). In both the smelter dusts and anode slimes, X-ray absorption spectroscopy indicates that about two thirds of the Te is present as reduced tellurides. In anode slimes, electron microscopy shows that the remaining Te is present in an oxidized form in a complex Te-bearing oxidate phase also containing Pb, Cu, Ag, As, Sb, and S. These results clearly indicate that more efficient, increased recovery of Te may be possible, likely at minimal expense from operating copper processing operations, thereby providing more Te for manufacturing of products such as inexpensive high-efficiency solar panels.

Understanding Growth Rate Limitations in Production of Single-Crystal Cadmium Zinc Telluride (CZT) by the Traveling Heater Method (THM)

NASA Astrophysics Data System (ADS)

Peterson, Jeffrey H.

Cadmium telluride (CdTe) and cadmium zinc telluride (CZT) are important optoelectronic materials with applications ranging from medical imaging to nuclear materials monitoring. However, CZT and CdTe have long been plagued by second-phase particles, inhomogeneity, and other defects. The traveling heater method (THM) is a promising approach for growing CZT and other compound semiconductors that has been shown to grow detector-grade crystals. In contrast to traditional directional solidification, the THM consists of a moving melt zone that simultaneously dissolves a polycrystalline feed while producing a single-crystal of material. Additionally, the melt is highly enriched in tellurium, which allows for growth at lower temperatures, limiting the presence of precipitated tellurium second-phase particles in the final crystal. Unfortunately, the THM growth of CZT is limited to millimeters per day when other growth techniques can grow an order of magnitude faster. To understand these growth limits, we employ a mathematical model of the THM system that is formulated to realistically represent the interactions of heat and species transport, fluid flow, and interfacial dissolution and growth under conditions of local thermodynamic equilibrium and steady-state growth. We examine the complicated interactions among zone geometry, continuum transport, phase change, and fluid flow driven by buoyancy. Of particular interest and importance is the formation of flow structures in the liquid zone of the THM that arise from the same physical mechanism as lee waves in atmospheric flows and demonstrate the same characteristic Brunt-Vaisala scaling. We show that flow stagnation and reversal associated with lee-wave formation are responsible for the accumulation of tellurium and supercooled liquid near the growth interface, even when the lee-wave vortex is not readily apparent in the overall flow structure. The supercooled fluid is posited to result in morphological instability at growth rates far below the limit predicted by the classical criterion by Tiller et al. for constitutional supercooling.

Luminescent Photoelectrochemical Cells. 5. Multiple Emission from Tellurium-Doped Cadmium Sulfide Photoelectrodes and Implications Regarding Excited-State Communication.

DTIC Science & Technology

1980-12-03

essentially invariant. Similar effects were observed for n-type, ZnO -based PECs and ascribed to a deficiency in the electron concentration needed for...California 92152 Dr. J. J. Auborn Dr. C. E. Mueller Bell Laboratories The Electrochemistry Branch Murray Hill, New Jersey 07974 Materials Division

Study of the effect of doping on the temperature stability of the optical properties of germanium single crystals

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

Podkopaev, O. I.; Shimanskiy, A. F., E-mail: shimanaf@mail.ru; Kopytkova, S. A.

2016-10-15

The effect of doping on the optical transmittance of germanium single crystals is studied by infrared Fourier spectroscopy. It is established that the introduction of silicon and tellurium additives into germanium doped with antimony provides a means for improving the temperature stability of the optical properties of the crystals.

Reconnaissance wadi-sediment geochemical survey of the Bi'r Jarbuah area, Kingdom of Saudi Arabia

USGS Publications Warehouse

Samater, Rashid M.; Christian, Ralph P.; Walker, Bruce M.

1990-01-01

Most of the ancient gold mines are also located along this contact. Gold is associated with arsenic but not with silver. Five areas containing gold-anomalies areas and 6 areas containing tellurium anomalies and the contact zone between the diorite and the paragneiss are recommended for further investigation of precious-metals resources.

10 CFR 30.72 - Schedule C-Quantities of radioactive materials requiring consideration of the need for an...

Code of Federal Regulations, 2012 CFR

2012-01-01

...-127m .01 5,000 Tellurium-129m .01 5,000 Terbium-160 .01 4,000 Thulium-170 .01 4,000 Tin-113 .01 10,000 Tin-123 .01 3,000 Tin-126 .01 1,000 Titanium-44 .01 100 Vanadium-48 .01 7,000 Xenon-133 1.0 900,000...

10 CFR 30.72 - Schedule C-Quantities of radioactive materials requiring consideration of the need for an...

Code of Federal Regulations, 2013 CFR

2013-01-01

...-127m .01 5,000 Tellurium-129m .01 5,000 Terbium-160 .01 4,000 Thulium-170 .01 4,000 Tin-113 .01 10,000 Tin-123 .01 3,000 Tin-126 .01 1,000 Titanium-44 .01 100 Vanadium-48 .01 7,000 Xenon-133 1.0 900,000...

10 CFR 30.72 - Schedule C-Quantities of radioactive materials requiring consideration of the need for an...

Code of Federal Regulations, 2014 CFR

2014-01-01

...-127m .01 5,000 Tellurium-129m .01 5,000 Terbium-160 .01 4,000 Thulium-170 .01 4,000 Tin-113 .01 10,000 Tin-123 .01 3,000 Tin-126 .01 1,000 Titanium-44 .01 100 Vanadium-48 .01 7,000 Xenon-133 1.0 900,000...

THORIUM DISPERSION IN BISMUTH

DOEpatents

Bryner, J.S.

1961-07-01

The growth of thorium bismutaide particles, which are formed when thorium is suspended in liquid bismuth, is inhibited when the liquid metal suspension is being flowed through a reactor and through a heat exchanger in sequence. It involves the addition of as little as 1 part by weight of tellurium to 100 parts of thorium. This addition is sufficient to inhibit particle growth and agglomeration.

Acousto-optic control of internal acoustic reflection in tellurium dioxide crystal in case of strong elastic energy walkoff [Invited].

PubMed

Voloshinov, Vitaly; Polikarpova, Nataliya; Ivanova, Polina; Khorkin, Vladimir

2018-04-01

Peculiar cases of acoustic wave propagation and reflection may be observed in strongly anisotropic acousto-optical crystals. A tellurium dioxide crystal serves as a prime example of such media, since it possesses record indexes of acoustic anisotropy. We studied one of the unusual scenarios of acoustic incidence and reflection from a free crystal-vacuum boundary in paratellurite. The directions of the acoustic waves in the (001) plane of the crystal were determined, and their basic characteristics were calculated. The carried-out acousto-optic experiment at the wavelength of light 532 nm and the acoustic frequency 73 MHz confirmed the theoretical predictions. The effects examined in the paper include the acoustic wave propagation with the record walkoff angle 74°. We also observed the incidence of the wave on the boundary at the angle exceeding 90°. Finally, we registered the close-to-back reflection of acoustic energy following the incidence. One of the stunning aspects is the distribution of energy between the incident and the back-reflected wave. The unusual features of the acoustic wave reflections pointed out in the paper are valuable for their possible applications in acousto-optic devices.

Comparative Genomics Analysis of a New Exiguobacterium Strain from Salar de Huasco Reveals a Repertoire of Stress-Related Genes and Arsenic Resistance.

PubMed

Castro-Severyn, Juan; Remonsellez, Francisco; Valenzuela, Sandro L; Salinas, Cesar; Fortt, Jonathan; Aguilar, Pablo; Pardo-Esté, Coral; Dorador, Cristina; Quatrini, Raquel; Molina, Franck; Aguayo, Daniel; Castro-Nallar, Eduardo; Saavedra, Claudia P

2017-01-01

The Atacama Desert hosts diverse ecosystems including salt flats and shallow Andean lakes. Several heavy metals are found in the Atacama Desert, and microorganisms growing in this environment show varying levels of resistance/tolerance to copper, tellurium, and arsenic, among others. Herein, we report the genome sequence and comparative genomic analysis of a new Exiguobacterium strain, sp. SH31, isolated from an altiplanic shallow athalassohaline lake. Exiguobacterium sp. SH31 belongs to the phylogenetic Group II and its closest relative is Exiguobacterium sp. S17, isolated from the Argentinian Altiplano (95% average nucleotide identity). Strain SH31 encodes a wide repertoire of proteins required for cadmium, copper, mercury, tellurium, chromium, and arsenic resistance. Of the 34 Exiguobacterium genomes that were inspected, only isolates SH31 and S17 encode the arsenic efflux pump Acr3. Strain SH31 was able to grow in up to 10 mM arsenite and 100 mM arsenate, indicating that it is arsenic resistant. Further, expression of the ars operon and acr3 was strongly induced in response to both toxics, suggesting that the arsenic efflux pump Acr3 mediates arsenic resistance in Exiguobacterium sp. SH31.

A monotopic aluminum telluride with an Al=Te double bond stabilized by N-heterocyclic carbenes

PubMed Central

Franz, Daniel; Szilvási, Tibor; Irran, Elisabeth; Inoue, Shigeyoshi

2015-01-01

Aluminum chalcogenides are mostly encountered in the form of bulk aluminum oxides that are structurally diverse but typically consist of networks with high lattice energy in which the chalcogen atoms bridge the metal centres. This makes their molecular congeners difficult to synthesize because of a pronounced tendency for oligomerization. Here we describe the isolation of the monotopic aluminum chalcogenide (LDipN)AlTe(LEt)2 (LDip=1,3-(2,6-diisopropylphenyl)-imidazolin-2-imine, LEt=1,3-diethyl-4,5-dimethyl-imidazolin-2-ylidene). Unique features of (LDipN)AlTe(LEt)2 are the terminal position of the tellurium atom, the shortest aluminum–tellurium distance hitherto reported for a molecular complex and the highest bond order reported for an interaction between these elements, to the best of our knowledge. At elevated temperature (LDipN)AlTe(LEt)2 equilibrates with dimeric {(LDipN)AlTe(LEt)}2 in which the chalcogen atoms assume their common role as bridges between the metal centres. These findings demonstrate that (LDipN)AlTe(LEt)2 comprises the elusive Al=Te double bond in the form of an N-heterocyclic carbene-stabilized species. PMID:26612781

Growth of II-VI Solid Solutions in the Presence of a Rotating Magnetic Field

NASA Technical Reports Server (NTRS)

Gillies, D. C; Motakef, S.; Dudley, M.; Matyi, R.; Volz, H.

1999-01-01

The application of a rotating magnetic field (RMF)in the frequency range 60-400 Hz and field strength of the order of 2-8 mT to crystal growth has received increasing attention in recent years. To take full advantage of the control of fluid flow by the forces applied by the field, the liquid column must be electrically conducting. Also, the application of RMF to the directional solidification of a column of liquid can result in complete mixing in the resultant solid. Thus, the technique of RMF is suited to solvent zones and float zones where the composition of the liquid is more readily controlled. In the work we report on, numerical modeling has been applied to II-VI systems, particularly tellurium based traveling heater techniques (THM). Results for a spectrum of field strengths and acceleration levels will be presented. These show clearly the effects of competing buoyancy forces and electromagnetic stirring. Crystals of cadmium zinc telluride and mercury cadmium telluride have been grown terrestrially from a tellurium solvent zone. The effects of the RMF during these experiments will be demonstrated with micrographs showing etch pits, white beam x-ray synchrotron topographs and triple axis x-ray diffraction.

The Nature of Bonding in Bulk Tellurium Composed of One-Dimensional Helical Chains.

PubMed

Yi, Seho; Zhu, Zhili; Cai, Xiaolin; Jia, Yu; Cho, Jun-Hyung

2018-05-07

Bulk tellurium (Te) is composed of one-dimensional (1D) helical chains which have been considered to be coupled by van der Waals (vdW) interactions. However, on the basis of first-principles density functional theory calculations, we here propose a different bonding nature between neighboring chains: i.e., helical chains made of normal covalent bonds are connected together by coordinate covalent bonds. It is revealed that the lone pairs of electrons of Te atoms participate in forming coordinate covalent bonds between neighboring chains, where each Te atom behaves as both an electron donor to neighboring chains and an electron acceptor from neighboring chains. This ligand-metal-like bonding nature in bulk Te results in the same order of bulk moduli along the directions parallel and perpendicular to the chains, contrasting with the large anisotropy of bulk moduli in vdW crystals. We further find that the electron effective masses parallel and perpendicular to the chains are almost the same as each other, consistent with the observed nearly isotropic electrical resistivity. It is thus demonstrated that the normal/coordinate covalent bonds parallel/perpendicular to the chains in bulk Te lead to a minor anisotropy in structural and transport properties.

Antiparasitic activity of 1,3-dioxolanes containing tellurium in Trichomonas vaginalis.

PubMed

Sena-Lopes, Ângela; das Neves, Raquel Nascimento; Bezerra, Francisco Silvestre Brilhante; de Oliveira Silva, Mara Thais; Nobre, Patrick C; Perin, Gelson; Alves, Diego; Savegnago, Lucielli; Begnini, Karine Rech; Seixas, Fabiana Kommling; Collares, Tiago; Borsuk, Sibele

2017-05-01

The increased prevalence of metronidazole-resistant infections has resulted in a search for alternative drugs for the treatment of trichomoniasis. In the present study, we report the preparation and in vitro activity of three 1,3-dioxolanes that contain tellurium (PTeDOX 01, PTeDOX 02, and PTeDOX 03) against Trichomonas vaginalis. Six concentrations of these compounds were analyzed for in vitro activity against ATCC 30236 isolate of T. vaginalis. PTeDOX 01 reported a cytotoxic effect against 100% of T. vaginalis trophozoites at a final concentration of 90μM with an IC 50 of 60μM. The kinetic growth curve of trophozoites indicated that PTeDOX 01 reduced the growth by 22% at a concentration of 90μM after an exposure of 12h, and induced complete parasite death at 24h. It induced cytotoxicity of 44% at 90μM concentration but and had no effect in lower concentrations in a culture of CHO-K1 cells. These results confirmed that PTeDOX 01 is an important drug for the treatment of T. vaginalis, and should be evaluated in other infectious agents as well. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Gyrotropic effects in trigonal tellurium studied from first principles

NASA Astrophysics Data System (ADS)

Tsirkin, Stepan S.; Puente, Pablo Aguado; Souza, Ivo

2018-01-01

We present a combined ab initio study of several gyrotropic effects in p -doped trigonal tellurium (effects that reverse direction with the handedness of the spiral chains in the atomic structure). The key ingredients in our study are the k -space Berry curvature and intrinsic orbital magnetic moment imparted on the Bloch states by the chirality of the crystal structure. We show that the observed sign reversal with temperature of the circular photogalvanic effect can be explained by the presence of Weyl points near the bottom of the conduction band acting as sources and sinks of Berry curvature. The passage of a current along the trigonal axis induces a rather small parallel magnetization, which can nevertheless be detected by optical means (Faraday rotation of transmitted light) due to the high transparency of the sample. In agreement with experiment, we find that when infrared light propagates antiparallel to the current at low doping the current-induced optical rotation enhances the natural optical rotation. According to our calculations the plane of polarization rotates in the opposite sense to the bonded atoms in the spiral chains, in agreement with a recent experiment that contradicts earlier reports.

Structural modeling of djenkolic acid with sulfur replaced by selenium and tellurium.

PubMed

Melnikov, Petr; Nascimento, Valter A; Silva, Anderson F; Consolo, Lourdes Z Z

2014-04-17

The comparative structural modeling of djenkolic acid and its derivatives containing selenium and tellurium in chalcogen sites (Ch=Se, Te) has provided detailed information about the bond lengths and bond angles, filling the gap in what we know about the structural characteristics of these aminoacids. The investigation using the molecular mechanics technique with good approximation confirmed the available information on X-ray refinements for the related compounds methionine and selenomethionine, as well as for an estimate made earlier for telluromethionine. It was shown that the Ch-C(3) and Ch-C(4) bond lengths grow in parallel with the increasing anionic radii. Although the distances C-C, C-O, and C-N are very similar, the geometry of conformers is quite different owing to the possibility of rotation about four carbon atoms, hence the remarkable variability observed in dihedral angles. It was shown that the compounds contain a rigid block with two Ch atoms connected through a methylene group. The standard program Gaussian 03 with graphical interface Gaussview 4.1.2 has proved to be satisfactory tool for the structural description of less-common bioactive compositions when direct X-ray results are absent.

Biosynthesis of tellurium nanoparticles by Lactobacillus plantarum and the effect of nanoparticle-enriched probiotics on the lipid profiles of mice.

PubMed

Mirjani, Ruholah; Faramarzi, Mohammad Ali; Sharifzadeh, Mohammad; Setayesh, Neda; Khoshayand, Mohammad Reza; Shahverdi, Ahmad Reza

2015-10-01

Hypercholesterolemia is an important risk factor contributing to atherosclerosis and coronary heart disease. Lactic acid bacteria have attracted much attention regarding their promising effect on serum cholesterol levels. Tellurium (Te) is a rare element that has also gained considerable interest for its biological effects. There have been some recent in vivo reports on the reduction effect of Te on cholesterol content. In this study, Lactobacillus plantarum PTCC 1058 was employed for the intracellular biosynthesis of Te NPs. The UV-visible spectrum of purified NPs showed a peak at 214 nm related to the surface plasmon resonance of the Te NPs. Transmission electron microscopy showed that spherical nanoparticles without aggregation had the average size of 45.7 nm as determined by the laser scattering method. The energy dispersive X-ray pattern confirmed the presence of Te atoms without any impurities. A significant reduction was observed in group which received L. plantarum with or without Te NPs during propylthiouracil and cholesterol diet in compare with the control group which received just propylthiouracil and cholesterol. The levels of triglycerides also remarkably decrease (p<0.05) in mice given L. plantarum with intracellular Te NPs.

Harnessing Intracellular Biochemical Pathways for In Vitro Synthesis of Designer Tellurium Nanorods.

PubMed

Xiong, Ling-Hong; Cui, Ran; Zhang, Zhi-Ling; Tu, Jia-Wei; Shi, Yun-Bo; Pang, Dai-Wen

2015-10-28

Synthesizing nanomaterials of desired properties is a big challenge, which requires extremely harsh conditions and/or use of toxic materials. More recently developed in vivo methods have brought a different set of problems such as separation and purification of nanomaterials made in vivo. Here, a novel approach that harnesses cellular pathways for in vitro synthesis of high-quality tellurium nanorods with tunable lengths and optical properties is reported. It is first demonstrated that in vivo biochemical pathways could be used to synthesize Te nanorods via the intracellular reduction of TeO3(2-) in living Staphylococcus aureus cells. The pathways to set up a quasi-biological system for Te precursor formation are then utilized, which could further synthesize Te nanorods in vitro. This allows to successfully synthesize in vitro, under routine laboratory conditions, Te nanorods with uniform and tunable lengths, ranging from about 10 to 200 nm, and controllable optical properties with high molar extinction coefficients. The approach here should open new avenues for controllable, facile, and efficient synthesis of designer nanomaterials for diverse industrial and biomedical applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Explanation of the conductivity minimum in tin- and tellurium-doped bismuth

NASA Astrophysics Data System (ADS)

Roy, Arpita; Banerjee, Dipali; Bhattacharya, Ramendranarayan

1995-01-01

The presence of a minimum observed in the variation of conductivity of bismuth with impurity concentrations at a constant temperature (4.2 K) has remained unexplained for a long time. An attempt to explain this anomalous behavior is reported here. In order to do so, a calculation has been made to find the change in the number of free carriers in bismuth with the addition of impurities (donors or acceptors). The calculation has been made using simple parabolic bands. It is known that when tin or tellurium atoms are added as impurities to bismuth all of the atoms are ionized. It has been found here that the number of free carriers initially shows a slow rate of decrease (for donors) or a slow rate of increase (for acceptors) as the impurity concentration is increased, as long as the impurity concentration is small, i.e., as long as the shift of the Fermi level is small. For a higher impurity concentration the number of carriers increases at a rate equal to that of the impurity concentration. This finding, combined with the scattering by impurity ions, could explain the anomalous behavior satisfactorily.

Regenerable antioxidants-introduction of chalcogen substituents into tocopherols.

PubMed

Poon, Jia-Fei; Singh, Vijay P; Yan, Jiajie; Engman, Lars

2015-02-02

To improve the radical-trapping capacity of the natural antioxidants, alkylthio-, alkylseleno-, and alkyltelluro groups were introduced into all vacant aromatic positions in β-, γ- and δ-tocopherol. Reaction of the tocopherols with electrophilic chalcogen reagents generated by persulfate oxidation of dialkyl dichalcogenides provided convenient but low-yielding access to many sulfur and selenium derivatives, but failed in the case of tellurium. An approach based on lithiation of the appropriate bromo-tocopherol, insertion of chalcogen into the carbon-lithium bond, air-oxidation to a dichalcogenide, and final borohydride reduction/alkylation turned out to be generally applicable to the synthesis of all chalcogen derivatives. Whereas alkylthio- and alkylseleno analogues were generally poorer quenchers of lipid peroxyl radicals than the corresponding parents, all tellurium compounds showed a substantially improved radical-trapping activity. Introduction of alkyltelluro groups into the tocopherol scaffold also caused a dramatic increase in the regenerability of the antioxidant. In a two-phase lipid peroxidation system containing N-acetylcysteine as a water-soluble co-antioxidant the inhibition time was up to six-fold higher than that recorded for the natural antioxidants. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Enhancement of Thermoelectric Properties of PEDOT:PSS and Tellurium-PEDOT:PSS Hybrid Composites by Simple Chemical Treatment.

PubMed

Bae, Eun Jin; Kang, Young Hun; Jang, Kwang-Suk; Cho, Song Yun

2016-01-05

The thermoelectric properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PSS) and tellurium- PSS (Te- PSS) hybrid composites were enhanced via simple chemical treatment. The performance of thermoelectric materials is determined by their electrical conductivity, thermal conductivity, and Seebeck coefficient. Significant enhancement of the electrical conductivity of PSS and Te- PSS hybrid composites from 787.99 and 11.01 to 4839.92 and 334.68 S cm(-1), respectively was achieved by simple chemical treatment with H2SO4. The power factor of the developed materials could be effectively tuned over a very wide range depending on the concentration of the H2SO4 solution used in the chemical treatment. The power factors of the developed thermoelectric materials were optimized to 51.85 and 284 μW m(-1) K(-2), respectively, which represent an increase of four orders of magnitude relative to the corresponding parameters of the untreated thermoelectric materials. Using the Te- PSS hybrid composites, a flexible thermoelectric generator that could be embedded in textiles was fabricated by a printing process. This thermoelectric array generates a thermoelectric voltage of 2 mV using human body heat.

Enhanced Flexural Strength of Tellurium Nanowires/epoxy Composites with the Reinforcement Effect of Nanowires

NASA Astrophysics Data System (ADS)

Balguri, Praveen Kumar; Harris Samuel, D. G.; Aditya, D. B.; Vijaya Bhaskar, S.; Thumu, Udayabhaskararao

2018-02-01

Investigating the mechanical properties of polymer nanocomposite materials has been greatly increased in the last decade. In particular, flexural strength plays a major role in resisting bending and shear loads of a composite material. Here, one dimensional (1D) tellurium nanowires (TeNWs) reinforced epoxy composites have been prepared and the flexural properties of resulted TeNWs/epoxy nanocomposites are studied. The diameter and length of the TeNWs used to make TeNWs/epoxy nanocomposites are 21±2.5 nm and 697±87 nm, respectively. Plain and TeNWs/epoxy nanocomposites are characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). Furthermore, significant enhancement in the flexural strength of TeNWs/epoxy nanocomposite is observed in comparison to plain epoxy composite, i.e. flexural strength is increased by 65% with the addition of very little amount of TeNWs content (0.05 wt.%) to epoxy polymer. Structural details of plain and TeNWs/epoxy at micrometer scale were examined by scanning electron microscopy (SEM). We believe that our results provide a new type of semiconductor nanowires based high strength epoxy polymer nanocomposites.

Local bonding structure of tellurium and antimony in the phase change chalcogenides germanium-antimony-tellurium: A nuclear magnetic resonance study

NASA Astrophysics Data System (ADS)

Bobela, David C.

Recent technological applications of some chalcogenide materials, compounds containing a group VI atom, have prompted studies of the local atomic structure of the amorphous phase. In the case of Ge2Sb2Te 5, metastability in the local bonding structure is responsible for its usefulness as a phase-change memory material. There is no consensus on the exact phase-change mechanism, which is partly due to the inadequacy of standard scattering techniques to probe the structure of the amorphous phase. Nuclear magnetic resonance methods, on the other hand, are well suited to study local structural order even in the absence of a periodic lattice. In this technique, structural information is encoded as an oscillating voltage caused by the nuclear spin. For the tellurium isotope, 125Te (spin = 1/2 in the ground state), the dominant interaction comes from the core and valence electrons that carry angular momentum. This interaction is helpful in identifying Te sites of different local coordination since the number of neighboring atoms should markedly change the local electronic structure. The antimony isotope 125Sb has a spin = 5/2 in the ground state and possesses an asymmetric nuclear charge. This quadrupole moment will interact with an electric field gradient at the nuclear site, which is provided by an asymmetric electron cloud surrounding the nucleus. The frequency-space spectra will reflect the strength of the interaction as well as the symmetry of the local electronic environment. This work investigates the nuclear magnetic resonance spectrum of 125Te and 125Sb in the crystalline and amorphous forms of several GexSbyTe 1-x-y compounds where 0 < (x, y) < 1. Results from the crystalline phase 125Te data show a trend in the spectral position that can be related to the tellurium bonded to three and six neighbors. In the amorphous phase, the same trend is observed, and the nuclear magnetic resonance fingerprint of two-fold and three-fold coordinated tellurium is obtained. It is concluded, based upon this comparison that the Te atoms see a dramatically different bonding environment depending on which phase the lattice has. The 125Sb data for the crystalline phase indicate electric field gradients that are consistent with similarly bonded quadrupolar nuclei, such as Sb atoms in crystalline Sb or five-fold coordinated Sb in crystalline MnSb. The NMR data exemplify the consequences of combinatorial disorder on the spectra via the absence of certain line-shape features. In the amorphous phase, the electric field gradients are approximately seven times larger, and the fingerprints of both highly-symmetric and asymmetric antimony sites emerge. Details of field gradient, i.e. the magnitude and symmetry, are remarkably similar to those found in Sb containing compounds where the Sb sites are three-fold pyramidal, such as in crystalline Sb2X3 where X = O, S, or Se. The observations from the NMR data provide a critical litmus test for recent structural models of the amorphous phase. In particular, the amorphous phase data provides clear evidence that the Te atoms are two-fold and three-fold coordinated while the Sb atoms are most likely bonded in three-fold pyramidal configurations. These observations imply a structural model of the amorphous phase that agrees best with a models based upon the "8 minus n", or "8-n" rule for chemical bonding in amorphous semiconductors. Thus, the lattice of these compounds is arranged such that the constituent elements have enough bonds, on average, to satisfy their valence requirement. The implications of the NMR data on theoretical modeling data are immediate. Theoretical models of these systems must possess some aspect of the "8-n" mentality. With this idea as a foundation for physically realistic representations of the amorphous phase, the origin of the phase-change mechanism may be unraveled, which will ultimately speed the process of compositional optimization of phase-change materials.

Guided-Wave TeO2 Acousto-Optic Devices

DTIC Science & Technology

1991-01-12

In this research program, Guided-wave TeO2 Acousto - Optic Devices, the properties of surface acoustic waves on tellurium dioxide single crystal...surfaces has been studied for its potential applications as acousto - optic signal processing devices. Personal computer based numerical method has been...interaction with laser beams. Use of the acousto - optic probe, the surface acoustic wave velocity and field distribution have been obtained and compared

Simple, Fast, and Sensitive Method for Quantification of Tellurite in Culture Media▿

PubMed Central

Molina, Roberto C.; Burra, Radhika; Pérez-Donoso, José M.; Elías, Alex O.; Muñoz, Claudia; Montes, Rebecca A.; Chasteen, Thomas G.; Vásquez, Claudio C.

2010-01-01

A fast, simple, and reliable chemical method for tellurite quantification is described. The procedure is based on the NaBH4-mediated reduction of TeO32− followed by the spectrophotometric determination of elemental tellurium in solution. The method is highly reproducible, is stable at different pH values, and exhibits linearity over a broad range of tellurite concentrations. PMID:20525868

Aqueous synthesis of porous platinum nanotubes at room temperature and their intrinsic peroxidase-like activity.

PubMed

Cai, Kai; Lv, Zhicheng; Chen, Kun; Huang, Liang; Wang, Jing; Shao, Feng; Wang, Yanjun; Han, Heyou

2013-07-11

Platinum nanotubes (PtNTs) exhibiting high porosity were constructed by sacrificing the exterior of tellurium nanowires (TeNWs) and disintegrating the inner part spontaneously in aqueous solution at room temperature, in which the Kirkendall effect may play an important role. The present PtNTs exhibited intrinsic peroxidase-like activity in the presence of H2O2.

REMOVAL OF CERTAIN FISSION PRODUCT METALS FROM LIQUID BISMUTH COMPOSITIONS

DOEpatents

Dwyer, O.E.; Howe, H.E.; Avrutik, E.R.

1959-11-24

A method is described for purifying a solution of urarium in liquid bismuth containing at least one metal from the group consisting of selenium, tellurium, palladium, ruthenium, rhodium, niobium, and zirconium. The solution is contacted with zinc in an inert atmosphere to form a homogeneous melt, a solid zinc phase is formed, and the zinc phase containing the metal is separated from the melt.

In vivo and in vitro cloning and phenotype characterization of tellurite resistance determinant conferred by plasmid pTE53 of a clinical isolate of Escherichia coli.

PubMed

Burian, J; Tu, N; Kl'ucár, L; Guller, L; Lloyd-Jones, G; Stuchlík, S; Fejdi, P; Siekel, P; Turna, J

1998-01-01

A determinant encoding resistance against potassium tellurite (Te(r)) was discovered in a clinical isolate of Escherichia coli strain KL53. The strain formed typical black colonies on solid LB medium with tellurite. The determinant was located on a large conjugative plasmid designated pTE53. Electron-dense particles were observed in cells harboring pTE53 by electron microscopy. X-Ray identification analysis identified these deposits as elemental tellurium and X-ray diffraction analysis showed patterns typical of crystalline structures. Comparison with JCPDS 4-0554 (Joint Committee on Powder Diffraction Standards) reference data confirmed that these crystals were pure tellurium crystals. In common with other characterized Te(r) determinants, accumulation studies with radioactively labeled tellurite showed that reduced uptake of tellurite did not contribute to the resistance mechanism. Tellurite accumulation rates for E. coli strain AB1157 harboring pTE53 were twice higher than for the plasmid-free host strain. In addition, no efflux mechanism was detected. The potassium tellurite resistance determinant of plasmid pTE53 was cloned using both in vitro and in vivo techniques in low-copy-number vectors pACYC184 and mini-Mu derivative pPR46. Cloning of the functional Te(r) determinant into high-copy cloning vectors pTZ19R and mini-Mu derivatives pBEf and pJT2 was not successful. During in vivo cloning experiments, clones with unusual "white colony" phenotypes were found on solid LB with tellurite. All these clones were Mucts62 lysogens. Their tellurite resistance levels were in the same order as the wild type strains. Clones with the "white" phenotype had a 3.6 times lower content of tellurium than the tellurite-reducing strain. Transformation of a "white" mutant with a recombinant pACYC184 based Te(r) plasmid did not change the phenotype. However, when one clone was cured from Mucts62 the "white" phenotype reverted to the wild-type "black" phenotype. It was suggested that the "white" phenotype was the result of an insertional inactivation of an unknown chromosomal gene by Mucts62, which reduced the tellurite uptake.

Mineral resource of the month: tellurium

USGS Publications Warehouse

,

2013-01-01

The article offers information on tellerium, a rare and expensive metal. Tellerium is considered the 71st most abundant element in Earth's crust, along with platinum and palladium. The element belongs to the chalcogen chemical family, and is recovered as a byproduct of nonferrous metal mining. The global demand for tellerium has significantly increased due to the growth in solar cell production in the U.S. and Europe, and thermoplastics in China.

76 FR 16607 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Partial Rescission of Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-24

... phosphorus, more than 0.05 percent of selenium, or more than 0.01 percent of tellurium). Also excluded from....01 percent of aluminum, (3) 0.040 percent or less, in the aggregate, of phosphorus and sulfur, (4) 0... aggregate, of phosphorus and sulfur, (4) 0.008 percent or less of nitrogen, and (5) either not more than 0...

76 FR 67407 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Preliminary Results of Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-01

... percent of phosphorus, more than 0.05 percent of selenium, or more than 0.01 percent of tellurium). Also....01 percent of aluminum, (3) 0.040 percent or less, in the aggregate, of phosphorus and sulfur, (4) 0... phosphorus and sulfur, (4) 0.008 percent or less of nitrogen, and (5) either not more than 0.15 percent, in...

Statistical studies of selected trace elements with reference to geology and genesis of the Carlin gold deposit, Nevada

USGS Publications Warehouse

Harris, Michael; Radtke, Arthur S.

1976-01-01

Linear regression and discriminant analyses techniques were applied to gold, mercury, arsenic, antimony, barium, copper, molybdenum, lead, zinc, boron, tellurium, selenium, and tungsten analyses from drill holes into unoxidized gold ore at the Carlin gold mine near Carlin, Nev. The statistical treatments employed were used to judge proposed hypotheses on the origin and geochemical paragenesis of this disseminated gold deposit.

Raman scattering boson peak and differential scanning calorimetry studies of the glass transition in tellurium-zinc oxide glasses.

PubMed

Stavrou, E; Tsiantos, C; Tsopouridou, R D; Kripotou, S; Kontos, A G; Raptis, C; Capoen, B; Bouazaoui, M; Turrell, S; Khatir, S

2010-05-19

Raman scattering and differential scanning calorimetry (DSC) measurements have been carried out on four mixed tellurium-zinc oxide (TeO(2))(1 - x)(ZnO)(x) (x = 0.1, 0.2, 0.3, 0.4) glasses under variable temperature, with particular attention being given to the respective glass transition region. From the DSC measurements, the glass transition temperature T(g) has been determined for each glass, showing a monotonous decrease of T(g) with increasing ZnO content. The Raman study is focused on the low-frequency band of the glasses, the so-called boson peak (BP), whose frequency undergoes an abrupt decrease at a temperature T(d) very close to the respective T(g) values obtained by DSC. These results show that the BP is highly sensitive to dynamical effects over the glass transition and provides a means for an equally reliable (to DSC) determination of T(g) in tellurite glasses and other network glasses. The discontinuous temperature dependence of the BP frequency at the glass transition, along with the absence of such a behaviour by the high-frequency Raman bands (due to local atomic vibrations), indicates that marked changes of the medium range order (MRO) occur at T(g) and confirms the correlation between the BP and the MRO of glasses.

Comparative Genomics Analysis of a New Exiguobacterium Strain from Salar de Huasco Reveals a Repertoire of Stress-Related Genes and Arsenic Resistance

PubMed Central

Castro-Severyn, Juan; Remonsellez, Francisco; Valenzuela, Sandro L.; Salinas, Cesar; Fortt, Jonathan; Aguilar, Pablo; Pardo-Esté, Coral; Dorador, Cristina; Quatrini, Raquel; Molina, Franck; Aguayo, Daniel; Castro-Nallar, Eduardo; Saavedra, Claudia P.

2017-01-01

The Atacama Desert hosts diverse ecosystems including salt flats and shallow Andean lakes. Several heavy metals are found in the Atacama Desert, and microorganisms growing in this environment show varying levels of resistance/tolerance to copper, tellurium, and arsenic, among others. Herein, we report the genome sequence and comparative genomic analysis of a new Exiguobacterium strain, sp. SH31, isolated from an altiplanic shallow athalassohaline lake. Exiguobacterium sp. SH31 belongs to the phylogenetic Group II and its closest relative is Exiguobacterium sp. S17, isolated from the Argentinian Altiplano (95% average nucleotide identity). Strain SH31 encodes a wide repertoire of proteins required for cadmium, copper, mercury, tellurium, chromium, and arsenic resistance. Of the 34 Exiguobacterium genomes that were inspected, only isolates SH31 and S17 encode the arsenic efflux pump Acr3. Strain SH31 was able to grow in up to 10 mM arsenite and 100 mM arsenate, indicating that it is arsenic resistant. Further, expression of the ars operon and acr3 was strongly induced in response to both toxics, suggesting that the arsenic efflux pump Acr3 mediates arsenic resistance in Exiguobacterium sp. SH31. PMID:28377753

Microstructure and phase composition of hypoeutectic Te-Bi alloy as evaporation source for photoelectric cathode

NASA Astrophysics Data System (ADS)

Wang, Bao-guang; Yang, Wen-hui; Gao, Hong-ye; Tian, Wen-huai

2018-05-01

A hypoeutectic 60Te-40Bi alloy in mass percent was designed as a tellurium atom evaporation source instead of pure tellurium for an ultraviolet detection photocathode. The alloy was prepared by slow solidification at about 10-2 K·s-1. The microstructure, crystal structure, chemical composition, and crystallographic orientation of each phase in the as-prepared alloy were investigated by optical microscopy, scanning electron microscopy, X-ray diffraction, electron backscatter diffraction, and transmission electron microscopy. The experimental results suggest that the as-prepared 60Te-40Bi alloy consists of primary Bi2Te3 and eutectic Bi2Te3/Te phases. The primary Bi2Te3 phase has the characteristics of faceted growth. The eutectic Bi2Te3 phase is encased by the eutectic Te phase in the eutectic structure. The purity of the eutectic Te phase reaches 100wt% owing to the slow solidification. In the eutectic phases, the crystallographic orientation relationship between Bi2Te3 and Te is confirmed as {[0001]_{B{i_2}T{e_3}}}//{[1\\bar 21\\bar 3]_{Te}} and the direction of Te phase parallel to {[11\\bar 20]_{B{i_2}T{e_3}}} is deviated by 18° from Te N{(2\\bar 1\\bar 11)_{Te}}.

Walking Down the Chalcogenic Group of the Periodic Table: From Singlet to Triplet Organic Emitters.

PubMed

Kremer, Adrian; Aurisicchio, Claudia; De Leo, Federica; Ventura, Barbara; Wouters, Johan; Armaroli, Nicola; Barbieri, Andrea; Bonifazi, Davide

2015-10-19

The synthesis, X-ray crystal structures, ground- and excited-state UV/Vis absorption spectra, and luminescence properties of chalcogen-doped organic emitters equipped on both extremities with benzoxa-, benzothia-, benzoselena- and benzotellurazole (1X and 2X ) moieties have been reported for the first time. The insertion of the four different chalcogen atoms within the same molecular skeleton enables the investigation of only the chalcogenic effect on the organisation and photophysical properties of the material. Detailed crystal-structure analyses provide evidence of similar packing for 2O -2Se , in which the benzoazoles are engaged in π-π stacking and, for the heavier atoms, in secondary X⋅⋅⋅X and X⋅⋅⋅N bonding interactions. Detailed computational analysis shows that the arrangement is essentially governed by the interplay of van der Waals and secondary bonding interactions. Progressive quenching of the fluorescence and concomitant onset of phosphorescence features with gradually shorter lifetimes are detected as the atomic weight of the chalcogen heteroatom increases, with the tellurium-doped derivatives exhibiting only emission from the lowest triplet excited state. Notably, the phosphorescence spectra of the selenium and tellurium derivatives can be recorded even at room temperature; this is a very rare finding for fully organic emitters. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Current Status and Future Prospects of the SNO+ Experiment

DOE PAGES

Andringa, S.

2016-01-01

SNO+ ismore » a large liquid scintillator-based experiment located 2 km underground at SNOLAB, Sudbury, Canada. It reuses the Sudbury Neutrino Observatory detector, consisting of a 12 m diameter acrylic vessel which will be filled with about 780 tonnes of ultra-pure liquid scintillator. Designed as a multipurpose neutrino experiment, the primary goal of a search for the neutrinoless double-beta decay (0 ν β β ) of 130Te. In Phase I, the detector will be loaded with 0.3% natural tellurium, corresponding to nearly 800 kg of 130Te, with an expected effective Majorana neutrino mass sensitivity in the region of 55–133 meV, just above the inverted mass hierarchy. Recently, the possibility of deploying up to ten times more natural tellurium has been investigated, which would enable SNO+ to achieve sensitivity deep into the parameter space for the inverted neutrino mass hierarchy in the future. Additionally, SNO+ aims to measure reactor antineutrino oscillations, low energy solar neutrinos, and geoneutrinos, to be sensitive to supernova neutrinos, and to search for exotic physics. A first phase with the detector filled with water will begin soon, with the scintillator phase expected to start after a few months of water data taking. The 0 ν β β Phase I is foreseen for 2017.« less

Tellurium Distribution and Speciation in Contaminated Soils from Abandoned Mine Tailings: Comparison with Selenium.

PubMed

Qin, Hai-Bo; Takeichi, Yasuo; Nitani, Hiroaki; Terada, Yasuko; Takahashi, Yoshio

2017-06-06

The distribution and chemical species of tellurium (Te) in contaminated soil were determined by a combination of microfocused X-ray fluorescence (μ-XRF), X-ray diffraction (μ-XRD), and X-ray absorption fine structure (μ-XAFS) techniques. Results showed that Te was present as a mixture of Te(VI) and Te(IV) species, while selenium (Se) was predominantly present in the form of Se(IV) in the soil contaminated by abandoned mine tailings. In the contaminated soil, Fe(III) hydroxides were the host phases for Se(IV), Te(IV), and Te(VI), but Te(IV) could be also retained by illite. The difference in speciation and solubility of Se and Te in soil can result from different structures of surface complexes for Se and Te onto Fe(III) hydroxides. Furthermore, our results suggest that the retention of Te(IV) in soil could be relatively weaker than that of Te(VI) due to structural incorporation of Te(VI) into Fe(III) hydroxides. These findings are of geochemical and environmental significance for better understanding the solubility, mobility, and bioavailability of Te in the surface environment. To the best of our knowledge, this is the first study reporting the speciation and host phases of Te in field soil by the μ-XRF-XRD-XAFS techniques.

Synergetic effect of functional cadmium–tellurium quantum dots conjugated with gambogic acid for HepG2 cell-labeling and proliferation inhibition

PubMed Central

Xu, Peipei; Li, Jingyuan; Shi, Lixin; Selke, Matthias; Chen, Baoan; Wang, Xuemei

2013-01-01

We prepared and studied novel fluorescent nanocomposites based on gambogic acid (GA) and cadmium–tellurium (CdTe) quantum dots (CdTe QDs) modified with cysteamine for purpose of cancer cell labeling and combined treatment. The nanocomposites were denoted as GA-CdTe. Characterization results indicated that the CdTe QDs can readily bind onto cell plasma membranes and then be internalized into cancer cells for real-time labeling and tracing of human liver hepatocellular carcinoma cell line (HepG2) cells. GA-CdTe significantly enhanced drug accumulation in HepG2 cells and inhibited cancer cell proliferation. GA-CdTe nanocomposites also improved the drug action of GA molecules in HepG2 cells and induced the G2/M phase arrest of the cancer cell cycle, promoting cell apoptosis. Given the sensitive, pH-triggered release of GA-CdTe, the side effects of GA anticancer agents on normal cells/tissues in the blood circulation markedly decreased. Efficient drug release and accumulation in target tumor cells were also facilitated. Thus, the fluorescent GA-CdTe offered a new strategy for potential multimode cancer therapy and provided new channels for research into naturally-active compounds extracted from traditional Chinese medicinal plants. PMID:24109183

Synergetic effect of functional cadmium-tellurium quantum dots conjugated with gambogic acid for HepG2 cell-labeling and proliferation inhibition.

PubMed

Xu, Peipei; Li, Jingyuan; Shi, Lixin; Selke, Matthias; Chen, Baoan; Wang, Xuemei

2013-01-01

We prepared and studied novel fluorescent nanocomposites based on gambogic acid (GA) and cadmium-tellurium (CdTe) quantum dots (CdTe QDs) modified with cysteamine for purpose of cancer cell labeling and combined treatment. The nanocomposites were denoted as GA-CdTe. Characterization results indicated that the CdTe QDs can readily bind onto cell plasma membranes and then be internalized into cancer cells for real-time labeling and tracing of human liver hepatocellular carcinoma cell line (HepG2) cells. GA-CdTe significantly enhanced drug accumulation in HepG2 cells and inhibited cancer cell proliferation. GA-CdTe nanocomposites also improved the drug action of GA molecules in HepG2 cells and induced the G2/M phase arrest of the cancer cell cycle, promoting cell apoptosis. Given the sensitive, pH-triggered release of GA-CdTe, the side effects of GA anticancer agents on normal cells/tissues in the blood circulation markedly decreased. Efficient drug release and accumulation in target tumor cells were also facilitated. Thus, the fluorescent GA-CdTe offered a new strategy for potential multimode cancer therapy and provided new channels for research into naturally-active compounds extracted from traditional Chinese medicinal plants.

From selenium- to tellurium-based glass optical fibers for infrared spectroscopies.

PubMed

Cui, Shuo; Chahal, Radwan; Boussard-Plédel, Catherine; Nazabal, Virginie; Doualan, Jean-Louis; Troles, Johann; Lucas, Jacques; Bureau, Bruno

2013-05-10

Chalcogenide glasses are based on sulfur, selenium and tellurium elements, and have been studied for several decades regarding different applications. Among them, selenide glasses exhibit excellent infrared transmission in the 1 to 15 µm region. Due to their good thermo-mechanical properties, these glasses could be easily shaped into optical devices such as lenses and optical fibers. During the past decade of research, selenide glass fibers have been proved to be suitable for infrared sensing in an original spectroscopic method named Fiber Evanescent Wave Spectroscopy (FEWS). FEWS has provided very nice and promising results, for example for medical diagnosis. Then, some sophisticated fibers, also based on selenide glasses, were developed: rare-earth doped fibers and microstructured fibers. In parallel, the study of telluride glasses, which can have transmission up to 28 µm due to its atom heaviness, has been intensified thanks to the DARWIN mission led by the European Space Agency (ESA). The development of telluride glass fiber enables a successful observation of CO₂ absorption band located around 15 µm. In this paper we review recent results obtained in the Glass and Ceramics Laboratory at Rennes on the development of selenide to telluride glass optical fibers, and their use for spectroscopy from the mid to the far infrared ranges.

Quartz crystal microbalance detection of DNA single-base mutation based on monobase-coded cadmium tellurium nanoprobe.

PubMed

Zhang, Yuqin; Lin, Fanbo; Zhang, Youyu; Li, Haitao; Zeng, Yue; Tang, Hao; Yao, Shouzhuo

2011-01-01

A new method for the detection of point mutation in DNA based on the monobase-coded cadmium tellurium nanoprobes and the quartz crystal microbalance (QCM) technique was reported. A point mutation (single-base, adenine, thymine, cytosine, and guanine, namely, A, T, C and G, mutation in DNA strand, respectively) DNA QCM sensor was fabricated by immobilizing single-base mutation DNA modified magnetic beads onto the electrode surface with an external magnetic field near the electrode. The DNA-modified magnetic beads were obtained from the biotin-avidin affinity reaction of biotinylated DNA and streptavidin-functionalized core/shell Fe(3)O(4)/Au magnetic nanoparticles, followed by a DNA hybridization reaction. Single-base coded CdTe nanoprobes (A-CdTe, T-CdTe, C-CdTe and G-CdTe, respectively) were used as the detection probes. The mutation site in DNA was distinguished by detecting the decreases of the resonance frequency of the piezoelectric quartz crystal when the coded nanoprobe was added to the test system. This proposed detection strategy for point mutation in DNA is proved to be sensitive, simple, repeatable and low-cost, consequently, it has a great potential for single nucleotide polymorphism (SNP) detection. 2011 © The Japan Society for Analytical Chemistry

Enhancement of Thermoelectric Properties of PEDOT:PSS and Tellurium-PEDOT:PSS Hybrid Composites by Simple Chemical Treatment

PubMed Central

Jin Bae, Eun; Hun Kang, Young; Jang, Kwang-Suk; Yun Cho, Song

2016-01-01

The thermoelectric properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and tellurium-PEDOT:PSS (Te-PEDOT:PSS) hybrid composites were enhanced via simple chemical treatment. The performance of thermoelectric materials is determined by their electrical conductivity, thermal conductivity, and Seebeck coefficient. Significant enhancement of the electrical conductivity of PEDOT:PSS and Te-PEDOT:PSS hybrid composites from 787.99 and 11.01 to 4839.92 and 334.68 S cm−1, respectively was achieved by simple chemical treatment with H2SO4. The power factor of the developed materials could be effectively tuned over a very wide range depending on the concentration of the H2SO4 solution used in the chemical treatment. The power factors of the developed thermoelectric materials were optimized to 51.85 and 284 μW m−1 K−2, respectively, which represent an increase of four orders of magnitude relative to the corresponding parameters of the untreated thermoelectric materials. Using the Te-PEDOT:PSS hybrid composites, a flexible thermoelectric generator that could be embedded in textiles was fabricated by a printing process. This thermoelectric array generates a thermoelectric voltage of 2 mV using human body heat. PMID:26728992

Tellurium doping effect in avalanche-mode amorphous selenium photoconductive film

NASA Astrophysics Data System (ADS)

Park, Wug-Dong; Tanioka, Kenkichi

2014-11-01

Amorphous selenium (a-Se) high-gain avalanche rushing amorphous photoconductor (HARP) film has been used for highly sensitive imaging devices. To improve the spectral response of a-Se HARP photoconductive film at a long wavelength, the tellurium (Te) doping effect in an 8-μm-thick a-Se HARP film was investigated. The thickness of the Te-doped a-Se layer in the 8-μm-thick a-Se HARP films was varied from 60 to 120 nm. The signal current increases significantly due to the avalanche multiplication when the target voltage is increased over the threshold voltage. In the 8-μm-thick a-Se HARP film with a Te-doped layer, the spectral response at a long wavelength was improved in comparison with the a-Se HARP film without a Te-doped layer. In addition, the increase of the lag in the 8-μm-thick a-Se HARP target with a Te-doped layer of 120 nm is caused by the photoconductive lag due to the electrons trapped in the Te-doped layer. Based on the current-voltage characteristics, spectral response, and lag characteristics of the 8-μm-thick a-Se HARP targets, the Te-doped layer thickness of 90 nm is suitable for the 8-μm-thick a-Se HARP film.

Causes and Prevention of Structural Materials Failures in Naval Environments.

DTIC Science & Technology

1984-01-01

atomic hydrogen as the first step; (iii) creation of elastic-plastic zones near the crack tip region due to movement of dislocations under applied...sodium tellurate is added to the charging solution. There is a dramatic drop in hydrogen permeation current due to the reduction of the tellurate ...effect of tellurium which has been deposited. Thus it has been shown that the tellurate ion, an electron acceptor, can delay the production of hydrogen

The Influence of a Rotating Magnetic Field on Solidification from a Traveling Solvent Zone

NASA Technical Reports Server (NTRS)

Gillies, Donald C.

1997-01-01

Application of a high frequency rotating magnetic field (50-400Hz) (RMF) with a strength of the order of 1 mT can be used to influence the fluid flow in an electrically conductive melt. The advantage of the RMF during the traveling solvent zone method for growth of semiconductor materials will be discussed. Preliminary modeling results for cadmium telluride growth from a tellurium solvent zone will be discussed.

Two-Step Vapor/Liquid/Solid Purification

NASA Technical Reports Server (NTRS)

Holland, L. R.

1986-01-01

Vertical distillation system combines in single operation advantages of multiple zone refining with those of distillation. Developed specifically to load Bridgman-Stockbarger (vertical-solidification) growth ampoules with ultrapure tellurium and cadmium, system, with suitable modifications, serves as material refiner. In first phase of purification process, ampoule heated to drive off absorbed volatiles. Second phase, evaporator heated to drive off volatiles in charge. Third phase, slowly descending heater causes distillation from evaporator to growing crystal in ampoule.

Fluorine-Induced Chemiluminescence Detection of Biologically Methylated Tellurium, Selenium, and Sulfur Compounds and Methyldithiocarbhydrazide as a Formaldehyde Derivatization Reagent

NASA Astrophysics Data System (ADS)

Chasteen, Thomas Girard

1990-01-01

The first part of this dissertation describes capillary chromatography coupled to a fluorine-induced chemiluminescence detector as a sensitive method by which biologically methylated metalloids can be determined in the presence of high concentrations of potentially interfering molecules. With a wide linear range and excellent sensitivity, this method was applied to the detection of dimethyl selenide (DMSe), dimethyl diselenide (DMDSe), and dimethyl telluride (DMTe), often found in biological environments in the presence of interfering methylated sulfur gases, such as methanethiol, dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide. Detection limits for DMSe, DMDSe, and DMTe were 30, 9, and 7 picograms, respectively. This DMTe detection limit is the lowest reported to date for a volatile tellurium gas. A variety of selenium-resistant bacteria emitted mixtures of methylated sulfur/selenium gases when dosed with inorganic selenium salts in the presence of sulfur containing growth media. One of the gases detected was dimethyl selenenyl sulfide, CH_3SeSCH _3, reported here for the first time in headspace above microorganisms. In addition, this detector responded to reduced phosphorus compounds such as phosphine. The detection limit for this compound was 2.8 picograms. Detection limits for alkylated phosphines trimethyl and triethyl phosphine were 0.5 and 17 picograms respectively, based on the relative response of these compounds compared to dimethyl sulfide. This method can be used for the simultaneous determination of methylated sulfur, selenium, tellurium compounds found in biological systems. Part II of this dissertation describes work with methyldithiocarbhydrazide, a compound that has been synthesized for use as a derivatization reagent to capture formaldehyde in the gas phase. Chosen for its ability to react in a manner similar to 2,4-dinitrophenylhydrazine, this molecule was selected based on two structural characteristics: a hydrazine tag to react with and thereby capture carbonyls and a methyl sulfide group to allow for sensitive detection by fluorine-induced chemiluminescence. Although in the final analysis methyldithiocarbohydrazide failed as a successful means by which formaldehyde can be determined using gas chromatography in conjunction with fluorine-induced chemiluminescence, it did successfully derivatize formaldehyde in both solution and the gas phase without the need for low pH conditions.

Functions of MiRNA-128 on the regulation of head and neck squamous cell carcinoma growth and apoptosis.

PubMed

Hauser, Belinda; Zhao, Yuan; Pang, Xiaowu; Ling, Zhiqiang; Myers, Ernest; Wang, Paul; Califano, Joseph; Gu, Xinbin

2015-01-01

Incidence of head and neck squamous cell carcinoma (HNSCC) has continuously increased in past years while its survival rate has not been significantly improved. There is a critical need to better understand the genetic regulation of HNSCC tumorigenesis and progression. In this study, we comprehensively analyzed the function of miRNA-128 (miR-128) in the regulation of HNSCC growth and its putative targets in vitro and in vivo systems. The function and targets of miR-128 were investigated in human HNSCC cell lines (JHU-13 and JHU-22), which were stably transfected with the miR-128 gene using a lentiviral delivery system. The expression levels of miR-128 and its targeted proteins were analyzed with qRT-PCR, Western blotting and flow cytometry. The binding capacity of miRNA-128 to its putative targets was determined using a luciferase report assay. MTT, colony formation, and a tumor xenograft model further evaluated the effects of miR-128 on HNSCC growth. We generated two miR-128 stably transfected human HNSCC cell lines (JHU-13miR-128 and JHU-22miR-128). Enforced expression of miR-128 was detected in both cultured JHU-13miR-128 and JHU-22miR-128 cell lines, approximately seventeen to twenty folds higher than in vector control cell lines. miRNA-128 was able to bind with the 3'-untranslated regions of BMI-1, BAG-2, BAX, H3f3b, and Paip2 mRNAs, resulting in significant reduction of the targeted protein levels. We found that upregulated miR-128 expression significantly inhibited both JHU-13miR-128 and JHU-22miR-128 cell viability approximately 20 to 40%, and the JHU-22miR-128 tumor xenograft growth compared to the vector control groups. miR-128 acted as a tumor suppressor inhibiting the HNSCC growth by directly mediating the expression of putative targets. Our results provide a better understanding of miRNA-128 function and its potential targets, which may be valuable for developing novel diagnostic markers and targeted therapy.

Studies of the Electro-Optic Effect.

DTIC Science & Technology

1983-01-01

electro - optic effect in crystalline solids has been pursued by employing a tight-binding theory for dielectric susceptibilities. The electronic and lattice contributions to the second-order electro - optic susceptibility have been treated separately and the lattice response of a crystal to an external dc electric field has been investigated in a general formalism. The theory has been specifically applied to the compound, tellurium dioxide. In addition, an experimental determination of the electro - optic coefficient, re, in thallium

Chalcogenide Glasses. Part 3. Chalcogenide Glass-Forming Systems.

DTIC Science & Technology

1986-02-01

34.L •. - . . . . . . . . ....... * .- . -.. . .. .. 8. Ti - As - S 31 9. As - Sb - S and As - Sb - Se 37 10. As - Halogen - (S, Se or Te) 40 11. As...Glass Forming Region and Tg in Ge-Sb-Se System 54[Ref. 40 ] 30 Glass Forming Region in Ge-Bi-S System [Ref.78] 55 31 Glass Forming Region in Ge-Bi-Se...poise), indicating the presence of tellurium chains. * p.° ~ -7 .. . *. 2. . * . . -~ ?’ ~ ~ - .. -~. r; - - - -•.~ ~ ~ ~ ~ * . 40 However, it rapidly

Energetic Materials and Metals Contamination at CFB/ASU Wainwirght, Alberta Phase 1

DTIC Science & Technology

2008-11-01

Edmonton, Alberta). Metals analyzed for this study were silver (Ag), aluminium (Al), arsenic (As), boron (B), barium (Ba), beryllium (Be), bismuth 4...selenium (Se), antimony (Sb), tin (Sn), strontium (Sr), tellurium (Te), titanium (Ti), thallium (Tl), uranium (U), vanadium (V), zinc (Zn), and...mg/kg mg/kg mg/kg Aluminium - 9070 1040 Antimony 40 2 1 Arsenic 12 7 13.6 Barium 2000 177 73.4 Beryllium 8 40 40 Bismuth - 20 20 Boron - 10

Synthesis and Structural Characterization of New Light Molecular Weight Inorganic Oxidizers and Related Derivatives. Volume: 2

DTIC Science & Technology

1993-02-01

of the strong inductive effect of the five fluorine ligands attached to the tellurium atom. 34 It is prepared under anhydrous conditions according to...MOLECULAR WEIGHT INORGANIC OXIDIZERS AND RELATED DERIVATIVES. VOLUME: II Professor G. J. Schrobilgen McMaster University Department of Chemistry...C: F04611-91-K-0004 Molecular Weight Inorganic Oxidizers and Relative PE: 62302F SDerivatives: Volume II 1PR: 5730 6. AUTHOFR(S) TA: 0*( C

Development of F.T. Raman Spectroscopy

DTIC Science & Technology

1989-06-19

vibrations of. the OHO group. The work nears completion. ’a have examined a range of tellurium organometallics and their z_-plexes. The high quality of-the...chemistry. High oxidation states of Mo, VIv, MnVI. Curi , Fe r r’ and several others have been identified as problematic since absorption of the laser...polymers is in hand. In these, spectral charges through and above the melting point are of interest. Several fibre systems have been studied including

Semiconductive materials and associated uses thereof

DOEpatents

Lynn, Kelvin [Pullman, WA; Jones, Kelly [Colfax, WA; Ciampi, Guido [Waltham, MA

2011-11-01

High rate radiation detectors are disclosed herein. The detectors include a detector material disposed inside the container, the detector material containing cadmium, tellurium, and zinc, a first dopant containing at least one of aluminum, chlorine, and indium, and a second dopant containing a rare earth metal. The first dopant has a concentration of about 500 to about 20,000 atomic parts per billion, and the second dopant has a concentration of about 200 to about 20,000 atomic parts per billion.

Semiconductive materials and associated uses thereof

DOEpatents

Lynn, Kelvin; Jones, Kelly; Ciampi, Guido

2012-10-09

High rate radiation detectors are disclosed herein. The detectors include a detector material disposed inside the container, the detector material containing cadmium, tellurium, and zinc, a first dopant containing at least one of aluminum, chlorine, and indium, and a second dopant containing a rare earth metal. The first dopant has a concentration of about 500 to about 20,000 atomic parts per billion, and the second dopant has a concentration of about 200 to about 20,000 atomic parts per billion.

Secondary power-producing cell. [electrodes contain same two elements in different proportions

DOEpatents

Fischer, A.K.

1971-10-26

This cell consists of an anode and a cathode containing the same two elements in different proportions and an electrolyte which contains ions of the element which is to be transported through it. The electrodes consist of chromium, iron, lithium, sodium, cadmium, copper, or zinc and phosphorus, selenium, tellurium, sulfur, arsenic, or nitrogen. A method to heat the cathode in the regeneration cycle to transfer the electronegative component to the anode is provided. (RWR)

Catalytic antioxidants: regenerable tellurium analogues of vitamin E.

PubMed

Singh, Vijay P; Poon, Jia-fei; Engman, Lars

2013-12-20

In an effort to improve the chain-breaking capacity of the natural antioxidants, an octyltelluro group was introduced next to the phenolic moiety in β- and δ-tocopherol. The new vitamin E analogues quenched peroxyl radicals more efficiently than α-tocopherol and were readily regenerable by aqueous N-acetylcysteine in a simple membrane model composed of a stirring chlorobenzene/water two-phase system. The novel tocopherol analogues could also mimic the action of the glutathione peroxidase enzymes.

Tellurium - Should it be isotopically anomalous in the Allende meteorite

NASA Technical Reports Server (NTRS)

Heymann, D.; Dziczkaniec, M.

1981-01-01

Isotopically anomalous Te is a by-product of the nuclear processes in zones of supernovae that have been proposed as sources for isotopically anomalous Xe. The calculated composition of the anomalous Te is roughly consistent with the disputed measurements made by Ballad et at. (1979) and Oliver et al. (1979) of samples of the Allende meteorite, with the exception that the large Te-123 overabundance reported by Oliver et al. (1979) is not predicted by the theory.

Materials Characterization and Microelectronic Implementation of Metal-insulator Transition Materials and Phase Change Materials

DTIC Science & Technology

2015-03-26

appropriate. Group 16 (VI) contains the following elements: Oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and polonium (Po). They are shown...below in Figure 33. S, Se, and Te are referred to as chalcogens, and their compounds are chalcogenides [68]. Polonium is excluded from the chalcogen...temperature dots and paint were placed on samples on the substrate. Temperature dots are typically used in the transportation of goods such as food in order

Leaching of cadmium and tellurium from cadmium telluride (CdTe) thin-film solar panels under simulated landfill conditions

PubMed Central

Ramos-Ruiz, Adriana; Wilkening, Jean V.; Field, James A.; Sierra-Alvarez, Reyes

2017-01-01

A crushed non-encapsulated CdTe thin-film solar cell was subjected to two standardized batch leaching tests (i.e., Toxicity Characteristic Leaching Procedure (TCLP) and California Waste Extraction Test (WET)) and to a continuous-flow column test to assess cadmium (Cd) and tellurium (Te) dissolution under conditions simulating the acidic- and the methanogenic phases of municipal solid waste landfills. Low levels of Cd and Te were solubilized in both batch leaching tests (<8.2% and <3.6% of added Cd and Te, respectively). On the other hand, over the course of 30 days, 73% of the Cd and 21% of the Te were released to the synthetic leachate of a continuous-flow column simulating the acidic landfill phase. The dissolved Cd concentration was 3.24-fold higher than the TCLP limit (1 mg L-1), and 650-fold higher than the maximum contaminant level established by the US-EPA for this metal in drinking water (0.005 mg L-1). In contrast, the release of Cd and Te to the effluent of the continuous-flow column simulating the methanogenic phase of a landfill was negligible. The remarkable difference in the leaching behavior of CdTe in the columns is related to different aqueous pH and redox conditions promoted by the microbial communities in the columns, and is in agreement with thermodynamic predictions. PMID:28472709

New volatile selenium and tellurium species in fermentation gases produced by composting duck manure

NASA Astrophysics Data System (ADS)

Pinel-Raffaitin, P.; Pécheyran, C.; Amouroux, D.

The occurrence of volatile metal(loid) compounds is investigated in gases released from a compost composed of pine shavings, duck feathers and duck excreta. The fermentation gases were sampled using Tedlar bags, pre-concentrated with cryogenic trap and finally analysed by cryo-trapping followed by gas chromatography hyphenated to inductively coupled mass spectrometry (CT-GC-ICPMS). In addition to arsenic (As), bismuth (Bi), lead (Pb), antimony (Sb) and tin (Sn) volatile species, up to eight selenium (Se) and seven tellurium (Te) species, namely methylated, ethylated and mixed methyl-ethylated ones, are detected for the first time. Although few volatile species standards are available, their identification or semi-identification is established by using quantitative structure-activity relationship (QSAR) through the correlation between boiling point and retention time of each compound. Their semi-quantification highlights maximal concentrations ranging from 30 to 2300 ng m -3 for Se species and from 10 to 500 ng m -3 for Te species. The variations of their concentrations are examined by emphasizing the influences of both compost nature and compost maturation stage. Finally, the results obtained in this study outline the diversity and the quantity of Se and Te species especially in comparison with other fermentation gases. Their release could thus induce "olfactory pollution" and potential sanitary and environmental impacts if no effluent treatment is applied during the compost production.

The microstructure and composition of equilibrium phases formed in hypoeutectic Te-In alloy during solidification

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

Wang, Baoguang

As a key tellurium atoms evaporation source for ultraviolet detection photocathode, the hypoeutectic Te{sub 75}In{sub 25} alloy was prepared by employing a slow solidification speed of about 10{sup −2} K/s. The microstructure and chemical composition of the equilibrium phases formed in the as-prepared alloy were studied in this research work. The experimental results show that the as-prepared Te-In alloy was constituted by primary In{sub 2}Te{sub 5} phase and eutectic In{sub 2}Te{sub 5}/Te phases. The eutectic In{sub 2}Te{sub 5}/Te phases are distributed in the grain boundaries of primary In{sub 2}Te{sub 5} phase. With the slow solidification speed, a pure eutectic Temore » phase without any excessive indium solute was obtained, where Te content of eutectic Te phase is 100 mass%. Moreover, it can be considered that the stress between the In{sub 2}Te{sub 5} and Te phases plays an important role in reducing the tellurium vapor pressure in Te{sub 75}In{sub 25} alloy. - Highlights: • The microstructure of Te-In alloy as an evaporation source was analyzed. • A pure eutectic Te phase was obtained by using a slow solidification speed method. • The relation between vapor pressure and inner-stress in the alloy was discussed.« less

Enrichment and isolation of Bacillus beveridgei sp. nov., a facultative anaerobic haloalkaliphile from Mono Lake, California, that respires oxyanions of tellurium, selenium, and arsenic

USGS Publications Warehouse

Baesman, S.M.; Stolz, J.F.; Kulp, T.R.; Oremland, R.S.

2009-01-01

Mono Lake sediment slurries incubated with lactate and tellurite [Te(IV)] turned progressively black with time because of the precipitation of elemental tellurium [Te(0)]. An enrichment culture was established from these slurries that demonstrated Te(IV)-dependent growth. The enrichment was purified by picking isolated black colonies from lactate/Te(IV) agar plates, followed by repeated streaking and picking. The isolate, strain MLTeJB, grew in aqueous Te(IV)-medium if provided with a small amount of sterile solid phase material (e.g., agar plug; glass beads). Strain MLTeJB grew at high concentrations of Te(IV) (~8 mM) by oxidizing lactate to acetate plus formate, while reducing Te(IV) to Te(0). Other electron acceptors that were found to sustain growth were tellurate, selenate, selenite, arsenate, nitrate, nitrite, fumarate and oxygen. Notably, growth on arsenate, nitrate, nitrite and fumarate did not result in the accumulation of formate, implying that in these cases lactate was oxidized to acetate plus CO2. Strain MLTeJB is a low G + C Gram positive motile rod with pH, sodium, and temperature growth optima at 8.5-9.0, 0.5-1.5 M, and 40??C, respectively. The epithet Bacillus beveridgei strain MLTeJBT is proposed. ?? 2009 Springer.

Extracellular production of tellurium nanoparticles by the photosynthetic bacterium Rhodobacter capsulatus.

PubMed

Borghese, Roberto; Brucale, Marco; Fortunato, Gianuario; Lanzi, Massimiliano; Mezzi, Alessio; Valle, Francesco; Cavallini, Massimiliano; Zannoni, Davide

2016-05-15

The toxic oxyanion tellurite (TeO3(2-)) is acquired by cells of Rhodobacter capsulatus grown anaerobically in the light, via acetate permease ActP2 and then reduced to Te(0) in the cytoplasm as needle-like black precipitates. Interestingly, photosynthetic cultures of R. capsulatus can also generate Te(0) nanoprecipitates (TeNPs) outside the cells upon addition of the redox mediator lawsone (2-hydroxy-1,4-naphtoquinone). TeNPs generation kinetics were monitored to define the optimal conditions to produce TeNPs as a function of various carbon sources and lawsone concentration. We report that growing cultures over a 10 days period with daily additions of 1mM tellurite led to the accumulation in the growth medium of TeNPs with dimensions from 200 up to 600-700 nm in length as determined by atomic force microscopy (AFM). This result suggests that nucleation of TeNPs takes place over the entire cell growth period although the addition of new tellurium Te(0) to pre-formed TeNPs is the main strategy used by R. capsulatus to generate TeNPs outside the cells. Finally, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) analysis of TeNPs indicate they are coated with an organic material which keeps the particles in solution in aqueous solvents. Copyright © 2016 Elsevier B.V. All rights reserved.

Antifungal activity of biogenic tellurium nanoparticles against Candida albicans and its effects on squalene monooxygenase gene expression.

PubMed

Zare, Bijan; Sepehrizadeh, Zargham; Faramarzi, Mohammad Ali; Soltany-Rezaee-Rad, Mohammad; Rezaie, Sassan; Shahverdi, Ahmad Reza

2014-01-01

In this study, we evaluated the antifungal activity of biogenic tellurium nanoparticles (Te NPs) against Candida albicans (ATCC14053). In addition, the effect of these biogenic NPs on squalene monooxygenase activity and the squalene monooxygenase gene (ERG1) expression level was evaluated. Squalene monooxygenase is an important enzyme involved in the synthesis of ergosterol, cholesterol, and phytosterols. Because of the importance of the noted compound, the squalene monooxygenase gene could be considered a good antifungal target. Results showed that biogenic Te NPs had antifungal effect against C. albicans. The minimal fungicidal concentration-minimal inhibitory concentration ratios of the biogenic Te NPs revealed that these NPs exhibited fungicidal effects against the test strain. The results of an enzyme assay using quantitative high-performance liquid chromatography showed squalene accumulation in C. albicans cells because of enzyme inhibition. Real-time PCR analysis showed an increase in the expression of the ERG1 gene in C. albicans cells, which were treated with Te NPs (0.2 mg/mL). It is conclution that Te NPs can inhibit the squalene monooxygenase enzyme, and, as a result, this inhibition phenomenon can cause an increase in the expression level of the ERG1 gene. This is the first report of the anti-Candida effect of biogenic Te NPs and its possible mechanisms. © 2013 International Union of Biochemistry and Molecular Biology, Inc.

Evaluation of tellurium toxicity in transformed and non-transformed human colon cells.

PubMed

Vij, Puneet; Hardej, Diane

2012-11-01

Diphenyl ditelluride (DPDT) and tellurium tetrachloride (TeCl(4)) were evaluated for toxicity in transformed (HT-29, Caco-2) and non-transformed colon cells (CCD-18Co). Significant decreases in viability were observed with DPDT exposure in HT-29 (62.5-1000 μM), Caco-2 (31.25-1000 μM) and CCD-18Co cells (500-1000 μM) and with TeCl(4) in HT-29 (31.25-1000 μM), Caco-2 (31.25-1000 μM) and CCD-18Co cells (500-1000 μM). Light microscopy confirmed viability analysis. Significant increases in caspase 3/7 and 9 activity were observed with DPDT in HT-29 (500-1000 μM) and CCD-18Co cells (1000 μM) indicating apoptosis. No significant increases in caspases were seen with TeCl(4) indicating necrosis. Apoptosis or necrosis was confirmed with fluorescent staining (FITC-Annexin, Hoechst 33342 and Ethidium Homodimer). Significant decreases in GSH/GSSG ratio were observed with DPDT in HT-29 (62.5-1000 μM), and CCD-18Co cells (1000 μM) and with TeCl(4) in HT-29 (62.5-1000 μM) and CCD-18Co cells (250-1000 μM). We concluded that cells treated with DPDT resulted in apoptosis and TeCl(4) treatment in necrosis. GSH/GSSG ratio shifts indicate oxidative mechanisms are involved. Copyright © 2012 Elsevier B.V. All rights reserved.

Large Area Cd0.9Zn0.1Te Pixelated Detector: Fabrication and Characterization

NASA Astrophysics Data System (ADS)

Chaudhuri, Sandeep K.; Nguyen, Khai; Pak, Rahmi O.; Matei, Liviu; Buliga, Vladimir; Groza, Michael; Burger, Arnold; Mandal, Krishna C.

2014-04-01

Cd0.9Zn0.1Te (CZT) based pixelated radiation detectors have been fabricated and characterized for gamma ray detection. Large area CZT single crystals has been grown using a tellurium solvent method. A 10 ×10 guarded pixelated detector has been fabricated on a 19.5 ×19.5 ×5 mm3 crystal cut out from the grown ingot. The pixel dimensions were 1.3 ×1.3 mm2 and were pitched at 1.8 mm. A guard grid was used to reduce interpixel/inter-electrode leakage. The crystal was characterized in planar configuration using electrical, optical and optoelectronic methods prior to the fabrication of pixelated geometry. Current-voltage (I-V) measurements revealed a leakage current of 27 nA at an operating bias voltage of 1000 V and a resistivity of 3.1 ×1010 Ω-cm. Infrared transmission imaging revealed an average tellurium inclusion/precipitate size less than 8 μm. Pockels measurement has revealed a near-uniform depth-wise distribution of the internal electric field. The mobility-lifetime product in this crystal was calculated to be 6.2 ×10 - 3 cm2/V using alpha ray spectroscopic method. Gamma spectroscopy using a 137Cs source on the pixelated structure showed fully resolved 662 keV gamma peaks for all the pixels, with percentage resolution (FWHM) as high as 1.8%.

Tracing Tellurium and Its Nanostructures in Biology.

PubMed

Zare, Bijan; Nami, Mohammad; Shahverdi, Ahmad-Reza

2017-12-01

Tellurium (Te) is a semimetal rare element in nature. Together with oxygen, sulfur (S), and selenium (Se), Te is considered a member of chalcogen group. Over recent decades, Te applications continued to emerge in different fields including metallurgy, glass industry, electronics, and applied chemical industries. Along these lines, Te has recently attracted research attention in various fields. Though Te exists in biologic organisms such as microbes, yeast, and human body, its importance and role and some of its potential implications have long been ignored. Some promising applications of Te using its inorganic and organic derivatives including novel Te nanostructures are being introduced. Before discovery and straightforward availability of antibiotics, Te had considered and had been used as an antibacterial element. Antilishmaniasis, antiinflammatory, antiatherosclerotic, and immuno-modulating properties of Te have been described for many years, while the innovative applications of Te have started to emerge along with nanotechnological advances over the recent years. Te quantum dots (QDs) and related nanostructures have proposed novel applications in the biological detection systems such as biosensors. In addition, Te nanostructures are used in labeling, imaging, and targeted drug delivery systems and are tested for antibacterial or antifungal properties. In addition, Te nanoparticles show novel lipid-lowering, antioxidant, and free radical scavenging properties. This review presents an overview on the novel forms of Te, their potential applications, as well as related toxicity profiles.

Comparative Analysis of Supply Risk-Mitigation Strategies for Critical Byproduct Minerals: A Case Study of Tellurium.

PubMed

Bustamante, Michele L; Gaustad, Gabrielle; Alonso, Elisa

2018-01-02

Materials criticality assessment is a screening framework increasingly applied to identify materials of importance that face scarcity risks. Although these assessments highlight materials for the implicit purpose of informing future action, the aggregated nature of their findings make them difficult to use for guidance in developing nuanced mitigation strategy and policy response. As a first step in the selection of mitigation strategies, the present work proposes a modeling framework and accompanying set of metrics to directly compare strategies by measuring effectiveness of risk reduction as a function of the features of projected supply demand balance over time. The work focuses on byproduct materials, whose criticality is particularly important to understand because their supplies are inherently less responsive to market balancing forces, i.e., price feedbacks. Tellurium, a byproduct of copper refining, which is critical to solar photovoltaics, is chosen as a case study, and three commonly discussed byproduct-relevant strategies are selected: dematerialization of end-use product, byproduct yield improvement, and end-of-life recycling rate improvement. Results suggest that dematerialization will be nearly twice as effective at reducing supply risk as the next best option, yield improvement. Finally, due to its infrequent use at present and its dependence upon long product lifespans, recycling end-of-life products is expected to be the least effective option despite potentially offering other benefits (e.g., cost savings and environmental impact reduction).

Luminescent Photoelectrochemical Cells. 4. Electroluminescent Properties of Undoped and Tellurium-Doped Cadmium Sulfide Electrodes.

DTIC Science & Technology

1980-12-03

and/or Dist Special UnclassifiLed 26CURITY CLAIICATION OrY,.g PAWEWO 000 Ss~w" Introduction Anunderstanding of electrochemistry at semiconductor...studies: Electrolyte species capable of hole injection into the valence bands of n-type, semiconducting T102 SrTi’ 3 , CdS ,GaP ’ ZnO ,and GaAs...the denominator of (4) by using the total current as a measure of holes injected. If equations (1) and (2) truly describe the electrochemistry at the

GaAs High Breakdown Voltage Front and Back Side Processed Schottky Detectors for X-Ray Detection

DTIC Science & Technology

2007-11-01

front and back side processed, unintentionally doped bulk gallium -arsenic (GaAs) Schottky detectors and determined that GaAs detectors with a large...a few materials that fulfill these requirements are gallium -arsenic (GaAs) and cadmium-zinc-tellurium (CdZnTe or CZT). They are viable alternative...Whitehill, C.; Pospíšil, S.; Wilhem, I.; Doležal, Z.; Juergensen, H.; Heuken, M. Development of low-pressure vapour -phase epitaxial GaAs for medical imaging

Analysis of energy production with different photovoltaic technologies in the Colombian geography

NASA Astrophysics Data System (ADS)

Muñoz, Y.; Zafra, D.; Acevedo, V.; Ospino, A.

2014-06-01

This research has analyzed the photovoltaic technologies, Polycrystalline silicon, Monocrystalline Silicon, GIS, Cadmium Tellurium and Amorphous Silicon; in eight cities of the Colombian territory, in order to obtain a clear idea of what is the most appropriate for each city or region studied. PVsyst simulation software has been used to study in detail each photovoltaic technology, for an installed capacity of 100kW knowing the specific data of losses by temperature, mismatch, efficiency, wiring, angle inclination of the arrangement, among others

Bibliography of Soviet Laser Developments, Number 63, January-February 1983.

DTIC Science & Technology

1984-02-01

properties of oxide crystals free of iron ions. Crystal Research and Technology [GDR), no. 7, 1982, 885-889. (RZhF, 1/83, 1D941) 5. Lebedev, V.I., V.A...and Yu.F. Suslov (0). Tellurium films as coatings for output mirrors in CO 2 laser resonators. Sb 1, 36-37. (RZhR, 2/83, 2Ye228) 7. Detectors 185...T.V. Timofeyeva, T.M. Vember, and A.F. Kavtrev (0). Sensitized photorefraction in block polymethylmethacrylate .containing lightly oxidizing anthracene

Bibliography of Soviet Laser Developments, Number 48 July-August 1980.

DTIC Science & Technology

1981-07-01

equilibrium and thermodvnamic properties of alloys of erbium with tellurium in the solid state. Moskovskiv Cli. Vestnik. Khimiva, no. 4, 1980, 339-344. 3...processes in a gamma laser. Sb 12, 147-163. (RZhF, 7/80, 7DI140) 292. Vysotskiy, V.I., and R.N. Kuz’min (51,2). Focusing and channeling of neutrons and...metal-nitride- oxide - semiconductor structure and a laser CRT. KE, no. 7, 1980, 1585-1588. 55 359. Soroka, S.1., and S.I. Ratnikov (0). Hologram

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

Park Y. S.; Kale, T.; Wu, Q.

A series of diketopyrrolopyrrole(DPP)-based small molecules have been synthesized by palladium-catalyzed coupling reactions. Electron-donating moieties (benzothiophene, benzoselenophene, and benzotellurophene) are bridged by an electron-withdrawing DPP unit to generate donor-acceptor-donor (D-A-D) type molecules. We observe red-shifts in absorption spectra of these compounds by varying heteroatoms from sulfur to tellurium. In bulk heterojunction solar cells with [6,6]phenyl-C61-butyric acid methyl ester (PC61BM) as acceptor, we obtain power conversion efficiencies of 2.4% (benzothiophene), 4.1% (benzoselenophene), and 3.0% (benzotellurophene), respectively.

An Assessment of Binary Metallic Glasses: Correlations Between Structure, Glass Forming Ability and Stability (Preprint)

DTIC Science & Technology

2009-04-01

Cu, germanium and tellurium ," J. Mat. Sci., vol. 9, pp. 707-717, 1974. [29] A. Inoue, T. Zhang, K. Kita, and T. Masumoto, "Mechanical strengths...Toribuchi, K. Aoki, and T. Masumoto, "Formation of La-M- Cu (M=Ca, Sr or Ba) amorphous alloys and their oxidization and superconductivity," Trans. JIM...structure of Pd- Ge alloys glasses by pulsed neutron total scattering," presented at Proc. 4 th International Conference on Rapidly Quenched Metals

Design and Demonstration of an Acousto-Optic Time-Integrating Correlator with a Large a Parallel Gain

DTIC Science & Technology

1993-01-01

Deoxyribose nucleicacid DPP: Digital Post-Processor DREO Detence Research Establishment Ottawa RF: Radio Frequency TeO2 : tellurium dioxide TIC: Time... TeO2 is 620 m/s, a device with a 100-As aperture device is 62-mm long. To take advantage of the full interaction time of these Bragg cells, the whole...INCLUDED IN THE DIGITAL POST-PROCESSOR HARDWARE Characteristics of Bandwidth Center Frequency Bragg Cell glass (bulk 100 MHz 150 MHz interaction) iNbO3

Live-monitoring of Te inclusions laser-induced thermo-diffusion and annealing in CdZnTe crystals

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

Zappettini, A.; Zambelli, N.; Benassi, G.

2014-06-23

The presence of Te inclusions is one of the main factors limiting performances of CdZnTe crystals as X-ray detectors. We show that by means of infrared laser radiation it is possible to move and anneal tellurium inclusions exploiting a thermo-diffusion mechanism. The process is studied live during irradiation by means of an optical microscope equipment. Experimental conditions, and, in particular, energy laser fluence, for annealing inclusions of different dimensions are determined.

Collision attack against Tav-128 hash function

NASA Astrophysics Data System (ADS)

Hariyanto, Fajar; Hayat Susanti, Bety

2017-10-01

Tav-128 is a hash function which is designed for Radio Frequency Identification (RFID) authentication protocol. Tav-128 is expected to be a cryptographically secure hash function which meets collision resistance properties. In this research, a collision attack is done to prove whether Tav-128 is a collision resistant hash function. The results show that collisions can be obtained in Tav-128 hash function which means in other word, Tav-128 is not a collision resistant hash function.

Precise and absolute measurements of complex third-order optical susceptibility

NASA Astrophysics Data System (ADS)

Santran, Stephane; Canioni, Lionel; Cardinal, Thierry; Fargin, Evelyne; Le Flem, Gilles; Rouyer, Claude; Sarger, Laurent

2000-11-01

We present precise and absolute measurements of full complex third order optical susceptibility on different fused silica and original glasses composed of tellurium, titanium, niobium erbium. These materials are designed to be the key point for applications ranging form high power laser systems to optoelectronics, their nonlinear index of refraction is a major property and thus must be accurately known. Due to the accuracy and sensitivity of our technique, we have been able to find a large dispersion (more than 30%) of the non linear index of fused silica glasses as a function of their processing mode. On the other hand, measurements on tellurium glasses have shown very strong nonlinearities (40 times higher than fused silica), to be linked to the configurations of their cations and anions. Although the titanium and niobium glasses are less nonlinear, they can be promising matrices for addition of luminescent entities like erbium leading to very interesting laser amplification materials. The experimental set-up is a collinear pump-probe (orthogonally polarized) experiment using transient absorption technique. It is built with around a 100 femtosecond laser oscillator. A fast oscillating delay between the pump and the probe allows us to measure the electronic nonlinearity in quasi real-time. This experiment has the following specifications: an absolute measurement accuracy below 10% mainly due to the laser parameters characterization, a relative measurement accuracy of 1% and a resolution less than 5.10-24m2/V2(50 times less than fused silica).

Leaching of cadmium and tellurium from cadmium telluride (CdTe) thin-film solar panels under simulated landfill conditions.

PubMed

Ramos-Ruiz, Adriana; Wilkening, Jean V; Field, James A; Sierra-Alvarez, Reyes

2017-08-15

A crushed non-encapsulated CdTe thin-film solar cell was subjected to two standardized batch leaching tests (i.e., Toxicity Characteristic Leaching Procedure (TCLP) and California Waste Extraction Test (WET)) and to a continuous-flow column test to assess cadmium (Cd) and tellurium (Te) dissolution under conditions simulating the acidic- and the methanogenic phases of municipal solid waste landfills. Low levels of Cd and Te were solubilized in both batch leaching tests (<8.2% and <3.6% of added Cd and Te, respectively). On the other hand, over the course of 30days, 73% of the Cd and 21% of the Te were released to the synthetic leachate of a continuous-flow column simulating the acidic landfill phase. The dissolved Cd concentration was 3.24-fold higher than the TCLP limit (1mgL -1 ), and 650-fold higher than the maximum contaminant level established by the US-EPA for this metal in drinking water (0.005mgL -1 ). In contrast, the release of Cd and Te to the effluent of the continuous-flow column simulating the methanogenic phase of a landfill was negligible. The remarkable difference in the leaching behavior of CdTe in the columns is related to different aqueous pH and redox conditions promoted by the microbial communities in the columns, and is in agreement with thermodynamic predictions. Copyright © 2017 Elsevier B.V. All rights reserved.

Speciation and identification of tellurium-containing metabolites in garlic, Allium sativum.

PubMed

Anan, Yasumi; Yoshida, Miyuki; Hasegawa, Saki; Katai, Ryota; Tokumoto, Maki; Ouerdane, Laurent; Łobiński, Ryszard; Ogra, Yasumitsu

2013-09-01

Tellurium (Te) is a widely used metalloid in industry because of its unique chemical and physical properties. However, information about the biological and toxicological activities of Te in plants and animals is limited. Although Te is expected to be metabolized in organisms via the same pathway as sulfur and selenium (Se), no precise metabolic pathways are known in organisms, particularly in plants. To reveal the metabolic pathway of Te in plants, garlic, a well-known Se accumulator, was chosen as the model plant. Garlic was hydroponically cultivated and exposed to sodium tellurate, and Te-containing metabolites in the water extract of garlic leaves were identified using HPLC coupled with inductively coupled plasma mass spectrometry (ICP-MS) or electrospray tandem mass spectrometry (ESI-MS-MS). At least three Te-containing metabolites were detected using HPLC-ICP-MS, and two of them were subjected to HPLC-ESI-MS-MS for identification. The MS spectra obtained by ESI-MS-MS indicated that the metabolite was Te-methyltellurocysteine oxide (MeTeCysO). Then, MeTeCysO was chemically synthesized and its chromatographic behavior matched with that of the Te-containing metabolite in garlic. The other was assigned as cysteine S-methyltellurosulfide. These results suggest that garlic can assimilate tellurate, an inorganic Te compound, and tellurate is transformed into a Te-containing amino acid, the so-called telluroamino acid. This is the first report addressing that telluroamino acid is de novo synthesized in a higher plant.

Synthesis and structure of A4V6[Te2(4+)Te6+]O24 (A = K, Rb)-two new quaternary mixed-valent tellurium oxides.

PubMed

Zhu, Tianxiang; Qin, Jingui; Halasyamani, P Shiv

2011-09-14

Two new mixed-valent tellurium oxides with vanadium(V), A(4)V(6)[Te(2)(4+)Te(6+)]O(24) (A = K and Rb), have been synthesized by hydrothermal and conventional solid state techniques. Their structures were determined by single-crystal X-ray diffraction analysis. These two iso-structural compounds exhibit layered structural topologies consisting of [V(6)Te(3)O(24)](4-) anionic units. In these anionic structural units, a Te(6+)O(6) octahedron is connected to six VO(4) tetrahedra by corner-sharing to generate a [V(6)TeO(24)] unit, and each of these [V(6)TeO(24)] units are interconnected by sharing two Te(4+)O(3) polyhedra to complete the infinite [V(6)Te(3)O(24)](4-) sheets. Infrared spectroscopy, UV-Visible diffuse reflectance spectroscopy, and thermogravimetric analysis were also performed on these two compounds. Crystal data: K(4)V(6)Te(3)O(24), trigonal, space group R ̅3c (No. 167) with a = b = 9.7075(6) Å, c = 42.701(3) Å, V = 3484.9(4) Å(3), and Z = 6; Rb(4)V(6)Te(3)O(24), trigonal, space group R ̅3c (No. 167) with a = b = 9.8399(9) Å, c = 43.012(4) Å, V = 3606.6(6) Å(3), and Z = 6. This journal is © The Royal Society of Chemistry 2011

Tellurium speciation analysis using hydride generation in situ trapping electrothermal atomic absorption spectrometry and ruthenium or palladium modified graphite tubes.

PubMed

Yildirim, Emrah; Akay, Pınar; Arslan, Yasin; Bakirdere, Sezgin; Ataman, O Yavuz

2012-12-15

Speciation of tellurium can be achieved by making use of different kinetic behaviors of Te(IV) and Te(VI) upon their reaction with sodium borohydride using hydride generation. While Te(IV) can form H(2)Te, Te(VI) will not form any volatile species during the course of hydride formation and measurement by atomic absorption spectrometry. Quantitative reduction of Te(VI) was achieved through application of a microwave assisted prereduction of Te(VI) in 6.0 mol/L HCl solution. Enhanced sensitivity was achieved by in situ trapping of the generated H(2)Te species in a previously heated graphite furnace whose surface was modified using Pd or Ru. Overall efficiency for in situ trapping in pyrolytically coated graphite tube surface was found to be 15% when volatile analyte species are trapped for 60s at 300°C. LOD and LOQ values were calculated as 0.086 ng/mL and 0.29 ng/mL, respectively. Efficiency was increased to 46% and 36% when Pd and Ru surface modifiers were used, respectively. With Ru modified graphite tube 173-fold enhancement was obtained over 180 s trapping period with respect to ETAAS; the tubes could be used for 250 cycles. LOD values were 0.0064 and 0.0022 ng/mL for Pd and Ru treated ETAAS systems, respectively, for 180 s collection of 9.6 mL sample solution. Copyright © 2012 Elsevier B.V. All rights reserved.

Piezotronic effect in 1D van der Waals solid of elemental tellurium nanobelt for smart adaptive electronics

NASA Astrophysics Data System (ADS)

Gao, Shengjie; Wang, Yixiu; Wang, Ruoxing; Wu, Wenzhuo

2017-10-01

Emerging technologies in wearable systems demand that functional devices can adaptively interact with the human body, where mechanical stimuli are ubiquitous and abundant. However, the electrical manipulation of charge carriers underpins the operations of state-of-the-art devices, and the effective control of interfacial energetics for charge carriers by the dynamic mechanical stimuli is still a relatively unexplored degree of freedom for semiconductor nanodevices. Piezotronic effect in nanostructured piezoelectric semiconductors offers exciting opportunities in addressing the above challenges. Here we report the first experimental exploration of piezotronic effect in 1D van der Waals solid of p-type tellurium nanobelt and systematically investigate the strain-gated charge carriers transport properties. The strain-induced polarization charges at the [10\\bar{1}0] surfaces of Te nanobelt can modulate the electronic transport through the interfacial effect on the Schottky contacts and the volumetric effect on the conducting channel. The competing phenomenon between interfacial and volumetric effects has been studied for the first time in piezotronics. Our research allows the access to a broad range of characterization and application of Te nanomaterials for piezotronics and could guide the future study of piezotronic effect in other materials. This progress in piezotronics, together with emerging methods for deterministic production and assembly of nanomaterials, leads to compelling opportunities for research from basic studies of piezoelectricity and semiconductor properties in functional nanomaterials to the development of ‘smarter’ electronics and optoelectronics.

A Very Compact Rijndael S-Box

DTIC Science & Technology

2004-09-28

01101011 84 N4 108 6C 01101100 250 R 109 6D 01101101 133 s128 110 6E 01101110 61 S64 111 6F 01101111 186 n64 112 70 01110000 43 m 113 71 01110001 121...109 6D 01101101 133 s128 183 B7 10110111 134 C128 194 C2 11000010 135 T 128 93 5D 01011101 136 α8 231 E7 11100111 137 g128 50 32 00110010 138 N128 86

A Very Compact Rijndael S-box

DTIC Science & Technology

2005-05-17

6A 01101010 40 r8 107 6B 01101011 84 N4 108 6C 01101100 250 R 109 6D 01101101 133 s128 110 6E 01101110 61 S64 111 6F 01101111 186 n64 112 70 01110000...210 D2 11010010 132 l128 109 6D 01101101 133 s128 183 B7 10110111 134 C128 194 C2 11000010 135 T 128 93 5D 01011101 136 α8 231 E7 11100111 137 g128

MicroRNA-128b suppresses tumor growth and promotes apoptosis by targeting A2bR in gastric cancer

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

Wang, Ping; Guo, Xueyan; Zong, Wei

2015-11-27

MicroRNAs (miRNAs) play crucial roles in the development and progression of human cancers, including gastric cancer (GC). The discovery of miRNAs may provide a new and powerful tool for studying the mechanism, diagnosis, and treatment of GC. In this study, we aimed to investigate the role and mechanism of miR-128b in the development and progression of GC. Quantitative real-time PCR (qRT-PCR) was used to measure the expression level of miR-128b in GC tissues and cell lines. We found that miR-128b was significantly down-regulated in GC tissues and cell lines. In addition, over-expression of miR-128b inhibited GC cell proliferation, migration andmore » invasion of GC cells in vitro. Gain-of-function in vitro experiments further showed that the miR-128b mimic significantly promoted GC cell apoptosis. Subsequent dual-luciferase reporter assay identified one of the proto-oncogene A2bR as direct target of miR-128b. Therefore, our results indicate that miR-128b is a proto-oncogene miRNA that can suppresses GC proliferation and migration through down-regulation of the oncogene gene A2bR. Taken together, our results indicate that miR-128b could serve as a potential diagnostic biomarker and therapeutic option for human GC in the near future. - Highlights: • The expression of MiR-128b is significantly down-regulated in GC tissues and cell lines. • Ectopic expression of miR-128b directly affects cell proliferation, migration and invasion in vitro. • Overexpression of miR-128b increases apoptosis in GC cells. • A2bR is a candidate target gene of miR-128b. • MiR-128b represses cell proliferation, migration and invasion and promotes apoptosis by targeting A2bR in GC.« less

Results from the CUORE-0 experiment

DOE PAGES

Canonica, L.; Alduino, C.; Alfonso, K.; ...

2016-06-09

The CUORE-0 experiment searched for neutrinoless double beta decay in 130 Te using an array of 52 tellurium dioxide crystals, operated as bolometers at a temperature of 10 mK. It took data in the Gran Sasso National Laboratory (Italy) since March 2013 to March 2015. We present the results of a search for neutrinoless double beta decay in 9.8 kg-years 130 Te exposure that allowed us to set the most stringent limit to date on this half-life. The performance of the detector in terms of background and energy resolution is also reported.

Physical and structural properties of Sm3+ ions doped heavy metal oxide containing lanthanum-boro-telluirte glass

NASA Astrophysics Data System (ADS)

Madhu, A.; Eraiah, B.

2018-05-01

The structural studies of Tellurium oxide substituted by samarium oxide in lathanum-lead-boro-tellurite glass are successfully prepared with physical and optical parameters are determined. Due to the effect of increased number of non-bridging oxygen's in the glass samples few physical parameters are observed to be decreased. For the better structural analysis FTIR was carried out and transformation of BO3 → BO4 is observed. Most effective absorption coefficient OH- group was attained in the present work.

Growth of lead tin telluride crystals in gels

NASA Technical Reports Server (NTRS)

Barber, Patrick G.

1986-01-01

Improved gels and several geometries were investigated for use in growing crystals. The use of lead sulfide test crystals proved workable, but it was impossible to obtain and maintain a sufficiently concentrated telluride ion solution to successfully grow lead telluride crystals. It appears that oxygen in the solution is capable of oxidizing the telluride ion up to tellurium metal. The method may still be successful, but only if precautions are taken to eliminate dissolved oxygen from the gels and aqueous solutions and to maintain a suitable concentration of telluride, Te(2)-(aq.).

Building new discrete supramolecular assemblies through the interaction of iso-tellurazole N-oxides with Lewis acids and bases.

PubMed

Ho, Peter C; Jenkins, Hilary A; Britten, James F; Vargas-Baca, Ignacio

2017-10-13

The supramolecular macrocycles spontaneously assembled by iso-tellurazole N-oxides are stable towards Lewis bases as strong as N-heterocyclic carbenes (NHC) but readily react with Lewis acids such as BR 3 (R = Ph, F). The electron acceptor ability of the tellurium atom is greatly enhanced in the resulting O-bonded adducts, which consequently enables binding to a variety of Lewis bases that includes acetonitrile, 4-dimethylaminopyridine, 4,4'-bipyridine, triphenyl phosphine, a N-heterocyclic carbene and a second molecule of iso-tellurazole N-oxide.

7 CFR 1220.128 - Soybeans.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 10 2011-01-01 2011-01-01 false Soybeans. 1220.128 Section 1220.128 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.128 Soybeans. The term...

7 CFR 1220.128 - Soybeans.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Soybeans. 1220.128 Section 1220.128 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.128 Soybeans. The term...

MiRNA-128 regulates the proliferation and neurogenesis of neural precursors by targeting PCM1 in the developing cortex

PubMed Central

Zhang, Wei; Kim, Paul Jong; Chen, Zhongcan; Lokman, Hidayat; Qiu, Lifeng; Zhang, Ke; Rozen, Steven George; Tan, Eng King; Je, Hyunsoo Shawn; Zeng, Li

2016-01-01

During the development, tight regulation of the expansion of neural progenitor cells (NPCs) and their differentiation into neurons is crucial for normal cortical formation and function. In this study, we demonstrate that microRNA (miR)-128 regulates the proliferation and differentiation of NPCs by repressing pericentriolar material 1 (PCM1). Specifically, overexpression of miR-128 reduced NPC proliferation but promoted NPC differentiation into neurons both in vivo and in vitro. In contrast, the reduction of endogenous miR-128 elicited the opposite effects. Overexpression of miR-128 suppressed the translation of PCM1, and knockdown of endogenous PCM1 phenocopied the observed effects of miR-128 overexpression. Furthermore, concomitant overexpression of PCM1 and miR-128 in NPCs rescued the phenotype associated with miR-128 overexpression, enhancing neurogenesis but inhibiting proliferation, both in vitro and in utero. Taken together, these results demonstrate a novel mechanism by which miR-128 regulates the proliferation and differentiation of NPCs in the developing neocortex. DOI: http://dx.doi.org/10.7554/eLife.11324.001 PMID:26883496

Crew Meal in Node 1 Unity

NASA Image and Video Library

2009-09-07

S128-E-007979 (7 Sept. 2009) --- Crew members onboard the International Space Station share a meal in the Unity node while Space Shuttle Discovery remains docked with the station. Pictured from the left (bottom) are NASA astronauts Rick Sturckow, STS-128 commander; Tim Kopra and Jose Hernandez, both STS-128 mission specialists; along with Kevin Ford, STS-128 pilot; and John “Danny” Olivas, STS-128 mission specialist. Pictured from the left (top) are NASA astronaut Nicole Stott (mostly out of frame) and Canadian Space Agency astronaut Robert Thirsk, both Expedition 20 flight engineers; along with NASA astronaut Patrick Forrester, STS-128 mission specialist.

MicroRNA-128 inhibits proliferation and invasion of glioma cells by targeting COX-2.

PubMed

Lin, Yihai; Wu, Zhangyi

2018-06-05

MicroRNAs (miRNA), a class of small noncoding RNAs, regulates message RNA (mRNA) by targeting the 3'-untranslated region (3'-UTR) resulting in suppression of gene expression. In this study, we identified the expression and function of miR-128, which was found to be downregulated in glioma tissues and glioma cells by real time PCR. Overexpression of miR-128 mimics into LN229 and U251 cells could inhibit proliferation and invasion of glioma cells. However, the inhibitory effects of miR-128 mimics on the invasion and proliferation of glioma cells were reversed by overexpression of cyclooxygenase-2 (COX-2). Our data showed that COX-2 was a candidate target of miR-128. Luciferase activity of 3'-UTR of COX-2 was reduced in the presence of miR-128. Additionally, miR-128 obviously decreased COX-2 mRNA stability determined by real time PCR. Contrarily, we found that miR-128 inhibitor significantly increased the COX-2 mRNA expression, and elevated the protein expression of MMP9 and ki67, and promoted the proliferation of glioma cells. Furthermore, luciferase activity of the 3'-UTR was upregulated by miR-128 inhibitor. All of these results supported that miR-128 was a direct regulator of COX-2. Further studies proved that COX-2 was elevated in glioma tissues and its expression was negatively correlated with the levels of miR-128. These findings may establish miR-128 as a new potential target for the treatment of patients with gliomas. Copyright © 2018 Elsevier B.V. All rights reserved.

The novel mTORC1/2 dual inhibitor INK-128 suppresses survival and proliferation of primary and transformed human pancreatic cancer cells

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

Lou, Hai-zhou; Weng, Xiao-chuan; Pan, Hong-ming

Highlights: • INK-128 inhibits the survival and growth of human pancreatic cancer cells. • INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. • INK-128 blocks mTORC1/2 activation simultaneously in pancreatic cancer cells. • INK-128 down-regulates cyclin D1 and causes pancreatic cancer cell cycle arrest. • INK-128 significantly increases sensitivity of pancreatic cancer cells to gemcitabine. - Abstract: Pancreatic cancer has one of worst prognosis among all human malignancies around the world, the development of novel and more efficient anti-cancer agents against this disease is urgent. In the current study, we tested the potential effect of INK-128, a novel mammalianmore » target of rapamycin (mTOR) complex 1 and 2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells in vitro. Our results demonstrated that INK-128 concentration- and time-dependently inhibited the survival and growth of pancreatic cancer cells (both primary cells and transformed cells). INK-128 induced pancreatic cancer cell apoptosis and necrosis simultaneously. Further, INK-128 dramatically inhibited phosphorylation of 4E-binding protein 1 (4E-BP1), ribosomal S6 kinase 1 (S6K1) and Akt at Ser 473 in pancreatic cancer cells. Meanwhile, it downregulated cyclin D1 expression and caused cell cycle arrest. Finally, we found that a low concentration of INK-128 significantly increased the sensitivity of pancreatic cancer cells to gemcitabine. Together, our in vitro results suggest that INK-128 might be further investigated as a novel anti-cancer agent or chemo-adjuvant for pancreatic cancer treatment.« less

Bacteriophage-derived CHAP domain protein, P128, kills Staphylococcus cells by cleaving interpeptide cross-bridge of peptidoglycan.

PubMed

Sundarrajan, Sudarson; Raghupatil, Junjappa; Vipra, Aradhana; Narasimhaswamy, Nagalakshmi; Saravanan, Sanjeev; Appaiah, Chemira; Poonacha, Nethravathi; Desai, Srividya; Nair, Sandhya; Bhatt, Rajagopala Narayana; Roy, Panchali; Chikkamadaiah, Ravisha; Durgaiah, Murali; Sriram, Bharathi; Padmanabhan, Sriram; Sharma, Umender

2014-10-01

P128 is an anti-staphylococcal protein consisting of the Staphylococcus aureus phage-K-derived tail-associated muralytic enzyme (TAME) catalytic domain (Lys16) fused with the cell-wall-binding SH3b domain of lysostaphin. In order to understand the mechanism of action and emergence of resistance to P128, we isolated mutants of Staphylococcus spp., including meticillin-resistant Staphylococcus aureus (MRSA), resistant to P128. In addition to P128, the mutants also showed resistance to Lys16, the catalytic domain of P128. The mutants showed loss of fitness as shown by reduced rate of growth in vitro. One of the mutants tested was found to show reduced virulence in animal models of S. aureus septicaemia suggesting loss of fitness in vivo as well. Analysis of the antibiotic sensitivity pattern showed that the mutants derived from MRSA strains had become sensitive to meticillin and other β-lactams. Interestingly, the mutant cells were resistant to the lytic action of phage K, although the phage was able to adsorb to these cells. Sequencing of the femA gene of three P128-resistant mutants showed either a truncation or deletion in femA, suggesting that improper cross-bridge formation in S. aureus could be causing resistance to P128. Using glutathione S-transferase (GST) fusion peptides as substrates it was found that both P128 and Lys16 were capable of cleaving a pentaglycine sequence, suggesting that P128 might be killing S. aureus by cleaving the pentaglycine cross-bridge of peptidoglycan. Moreover, peptides corresponding to the reported cross-bridge of Staphylococcus haemolyticus (GGSGG, AGSGG), which were not cleaved by lysostaphin, were cleaved efficiently by P128. This was also reflected in high sensitivity of S. haemolyticus to P128. This showed that in spite of sharing a common mechanism of action with lysostaphin, P128 has unique properties, which allow it to act on certain lysostaphin-resistant Staphylococcus strains. © 2014 The Authors.

28 CFR 0.128 - Organization.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Organization. 0.128 Section 0.128 Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE DEPARTMENT OF JUSTICE 1-Foreign Claims Settlement Commission § 0.128 Organization. The Foreign Claims Settlement Commission of the United States is...

10 CFR 4.128 - New construction.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false New construction. 4.128 Section 4.128 Energy NUCLEAR... 1973, as Amended Discriminatory Practices § 4.128 New construction. (a) Design, construction, and... Federal Accessibility Standards. (1) Effective as of January 18, 1991, design, construction, or alteration...

10 CFR 4.128 - New construction.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false New construction. 4.128 Section 4.128 Energy NUCLEAR... 1973, as Amended Discriminatory Practices § 4.128 New construction. (a) Design, construction, and... Federal Accessibility Standards. (1) Effective as of January 18, 1991, design, construction, or alteration...

7 CFR 800.128 - Conflicts of interest.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Conflicts of interest. 800.128 Section 800.128 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD... Reinspection Services and Review of Weighing Services § 800.128 Conflicts of interest. Official personnel...

32 CFR 842.128 - Delegations of authority.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 6 2011-07-01 2011-07-01 false Delegations of authority. 842.128 Section 842.128 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE CLAIMS AND LITIGATION ADMINISTRATIVE CLAIMS Nonappropriated Fund Claims § 842.128 Delegations of authority. (a...

7 CFR 1703.128 - Submission of applications.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Submission of applications. 1703.128 Section 1703.128 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Grant Program § 1703.128 Submission of...

46 CFR 128.320 - Exhaust systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Exhaust systems. 128.320 Section 128.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Main and Auxiliary Machinery § 128.320 Exhaust systems. No diesel-engine exhaust system...

46 CFR 128.320 - Exhaust systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Exhaust systems. 128.320 Section 128.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Main and Auxiliary Machinery § 128.320 Exhaust systems. No diesel-engine exhaust system...

46 CFR 128.320 - Exhaust systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Exhaust systems. 128.320 Section 128.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Main and Auxiliary Machinery § 128.320 Exhaust systems. No diesel-engine exhaust system...

46 CFR 128.320 - Exhaust systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Exhaust systems. 128.320 Section 128.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Main and Auxiliary Machinery § 128.320 Exhaust systems. No diesel-engine exhaust system...

46 CFR 128.320 - Exhaust systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Exhaust systems. 128.320 Section 128.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Main and Auxiliary Machinery § 128.320 Exhaust systems. No diesel-engine exhaust system...

7 CFR 1703.128 - Submission of applications.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 11 2013-01-01 2013-01-01 false Submission of applications. 1703.128 Section 1703.128 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Grant Program § 1703.128 Submission of...

7 CFR 1703.128 - Submission of applications.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 11 2014-01-01 2014-01-01 false Submission of applications. 1703.128 Section 1703.128 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Grant Program § 1703.128 Submission of...

7 CFR 1703.128 - Submission of applications.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Submission of applications. 1703.128 Section 1703.128 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Grant Program § 1703.128 Submission of...

7 CFR 1703.128 - Submission of applications.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 11 2012-01-01 2012-01-01 false Submission of applications. 1703.128 Section 1703.128 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Grant Program § 1703.128 Submission of...

Crew Meal in Node 1 Unity

NASA Image and Video Library

2009-09-07

S128-E-007977 (7 Sept. 2009) --- Crew members onboard the International Space Station share a meal in the Unity node while Space Shuttle Discovery remains docked with the station. Pictured from the left (bottom) are NASA astronauts Rick Sturckow, STS-128 commander; Tim Kopra and Jose Hernandez, both STS-128 mission specialists; along with Kevin Ford, STS-128 pilot; and John “Danny” Olivas (mostly out of frame at right), STS-128 mission specialist. Pictured from the left (top, partially out of frame) are NASA astronaut Nicole Stott and Canadian Space Agency astronaut Robert Thirsk, both Expedition 20 flight engineers; along with NASA astronaut Patrick Forrester, STS-128 mission specialist.

41 CFR 128-1.8008 - Exemptions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Exemptions. 128-1.8008 Section 128-1.8008 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.80-Seismic Safety Program § 128-1.8008 Exemptions. The...

41 CFR 128-1.8007 - Reporting.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Reporting. 128-1.8007 Section 128-1.8007 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.80-Seismic Safety Program § 128-1.8007 Reporting. The...

7 CFR 762.128 - Environmental and special laws.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 7 2014-01-01 2014-01-01 false Environmental and special laws. 762.128 Section 762.128 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS GUARANTEED FARM LOANS § 762.128 Environmental and special laws. (a...

17 CFR 1.28 - Appraisal of instruments purchased with customer funds.

Code of Federal Regulations, 2010 CFR

2010-04-01

... purchased with customer funds. 1.28 Section 1.28 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION GENERAL REGULATIONS UNDER THE COMMODITY EXCHANGE ACT Customers' Money, Securities, and Property § 1.28 Appraisal of instruments purchased with customer funds. Futures commission merchants who...

10 CFR 4.128 - New construction.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false New construction. 4.128 Section 4.128 Energy NUCLEAR... 1973, as Amended Discriminatory Practices § 4.128 New construction. (a) Design, construction, and... Accessibility Standards. (1) Effective as of January 18, 1991, design, construction, or alteration of buildings...

10 CFR 4.128 - New construction.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false New construction. 4.128 Section 4.128 Energy NUCLEAR... 1973, as Amended Discriminatory Practices § 4.128 New construction. (a) Design, construction, and... Accessibility Standards. (1) Effective as of January 18, 1991, design, construction, or alteration of buildings...

28 CFR 0.128b - Regulations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Regulations. 0.128b Section 0.128b Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE DEPARTMENT OF JUSTICE 1-Foreign Claims Settlement Commission § 0.128b Regulations. All rules of practice and regulations applicable to the...

28 CFR 0.128b - Regulations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Regulations. 0.128b Section 0.128b Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE DEPARTMENT OF JUSTICE 1-Foreign Claims Settlement Commission § 0.128b Regulations. All rules of practice and regulations applicable to the...

15 CFR 923.128 - Revisions to assessments and strategies.

Code of Federal Regulations, 2010 CFR

2010-01-01

... strategies. 923.128 Section 923.128 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign... COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Coastal Zone Enhancement Grants Program § 923.128 Revisions to assessments and strategies. (a) A State, in consultation with the Assistant...

29 CFR 452.128 - Under-strength representation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 2 2010-07-01 2010-07-01 false Under-strength representation. 452.128 Section 452.128 Labor Regulations Relating to Labor OFFICE OF LABOR-MANAGEMENT STANDARDS, DEPARTMENT OF LABOR LABOR... AND DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members § 452.128 Under-strength...

29 CFR 452.128 - Under-strength representation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 2 2011-07-01 2011-07-01 false Under-strength representation. 452.128 Section 452.128 Labor Regulations Relating to Labor OFFICE OF LABOR-MANAGEMENT STANDARDS, DEPARTMENT OF LABOR LABOR... AND DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members § 452.128 Under-strength...

23 CFR 1.28 - Diversion of highway revenues.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 23 Highways 1 2012-04-01 2012-04-01 false Diversion of highway revenues. 1.28 Section 1.28 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GENERAL MANAGEMENT AND ADMINISTRATION GENERAL § 1.28 Diversion of highway revenues. (a) Reduction in apportionment. If the Secretary shall find...

Soil-to-crop transfer factors of tellurium.

PubMed

Yang, Guosheng; Zheng, Jian; Tagami, Keiko; Uchida, Shigeo

2014-09-01

Stable tellurium (Te) concentrations in 148 sets of agricultural soil and associated crop samples were measured in this study to obtain soil-to-crop transfer factor (TF) of Te. We used a recently developed simple method that applies digestion of samples with aqua regia and sector field inductively coupled plasma mass spectrometry to measure low Te levels in these samples. Geometric mean (GM) concentrations of Te in soil and crops were 75μgkg(-1)-dry (range: 15-850μgkg(-1)-dry) and 1.8μgkg(-1)-dry (range: 0.1-120μgkg(-1)-dry), respectively; the Te concentration range was significantly wider in crops than in soil. Using these data, we calculated TFs and obtained their range from 1.3×10(-3) to 1.1×10(-1). The GM of TF for upland field crops was calculated to be 2.0×10(-2) and for brown rice was 3.1×10(-2); all crop types had the similar GMs of their TF values. Data comparison for TF of Te was carried out with six elements, which are present in anionic forms in soil environment like Te is, i.e. P, Br, As, Se, Mo, and I. TFs of Te and I showed the highest correlation factor for upland field crops by t-test (r=0.577, p<0.001), but no correlation was found for brown rice. We considered it likely that different water management practices in upland fields and paddy fields affected the Te transfer from soil to crops. Copyright © 2014 Elsevier Ltd. All rights reserved.

Size distribution effects of cadmium tellurium quantum dots (CdS/CdTe) immunotoxicity on aquatic organisms.

PubMed

Bruneau, A; Fortier, M; Gagne, F; Gagnon, C; Turcotte, P; Tayabali, A; Davis, T L; Auffret, M; Fournier, M

2013-03-01

The increasing use of products derived from nanotechnology has raised concern about their potential toxicity to aquatic life. This study sought to examine the comparative immunotoxicity of capped cadmium sulphide/cadmium telluride (CdS/CdTe) quantum dots (QDs) and possible impact of particle/aggregate size on two bivalves (Mytilus edulis and Elliptio complanata) and a fish (Oncorhynchus mykiss). The QDs were dispersed in sterile water and fractionated using a series of micro/ultrafiltration membranes of decreasing pore size: 450 nm, 100 nm, 50 nm, 25 nm, 100 kDa (6.8 nm), 30 kDa (4.6 nm), 10 kDa (3.2 nm) and 1 kDa (1.5 nm). The total concentrations of cadmium and tellurium were determined for the filtered material and for that retained on the filters (retentate). The immunotoxicity was determined by measuring cell viability and phagocytosis. Results revealed that nanoparticles retained on the ultrafilters had a higher Cd/Te ratio compared to the permeate fraction (ratio of 5 and 2 respectively) which could indicate that the CdS core was not associated with the permeable fraction of Cd. Our results demonstrate that the toxicity of CdS/CdTe QDs was concentration and size dependent. Large CdS/CdTe QD aggregates (25 nm < size < 100 nm) reduced phagocytosis more than did smaller nanoparticles (<25 nm). Moreover, our results revealed that the different species responded differently to these fractions. Mytilus edulis hemocytes were less sensitive to CdS/CdTe QDs than the Oncorhynchus mykiss macrophage and Elliptio complanata hemocytes.

Formation of Tellurium Nanocrystals during Anaerobic Growth of Bacteria That Use Te Oxyanions as Respiratory Electron Acceptors▿

PubMed Central

Baesman, Shaun M.; Bullen, Thomas D.; Dewald, James; Zhang, Donghui; Curran, Seamus; Islam, Farhana S.; Beveridge, Terry J.; Oremland, Ronald S.

2007-01-01

Certain toxic elements support the metabolism of diverse prokaryotes by serving as respiratory electron acceptors for growth. Here, we demonstrate that two anaerobes previously shown to be capable of respiring oxyanions of selenium also achieve growth by reduction of either tellurate [Te(VI)] or tellurite [Te(IV)] to elemental tellurium [Te(0)]. This reduction achieves a sizeable stable-Te-isotopic fractionation (isotopic enrichment factor [ɛ] = −0.4 to −1.0 per ml per atomic mass unit) and results in the formation of unique crystalline Te(0) nanoarchitectures as end products. The Te(0) crystals occur internally within but mainly externally from the cells, and each microorganism forms a distinctly different structure. Those formed by Bacillus selenitireducens initially are nanorods (∼10-nm diameter by 200-nm length), which cluster together, forming larger (∼1,000-nm) rosettes composed of numerous individual shards (∼100-nm width by 1,000-nm length). In contrast, Sulfurospirillum barnesii forms extremely small, irregularly shaped nanospheres (diameter < 50 nm) that coalesce into larger composite aggregates. Energy-dispersive X-ray spectroscopy and selected area electron diffraction indicate that both biominerals are composed entirely of Te and are crystalline, while Raman spectroscopy confirms that they are in the elemental state. These Te biominerals have specific spectral signatures (UV-visible light, Raman) that also provide clues to their internal structures. The use of microorganisms to generate Te nanomaterials may be an alternative for bench-scale syntheses. Additionally, they may also generate products with unique properties unattainable by conventional physical/chemical methods. PMID:17277198

Formation of tellurium nanocrystals during anaerobic growth of bacteria that use Te oxyanions as respiratory electron acceptors

USGS Publications Warehouse

Baesman, S.M.; Bullen, T.D.; Dewald, J.; Zhang, Dongxiao; Curran, S.; Islam, F.S.; Beveridge, T.J.; Oremland, R.S.

2007-01-01

Certain toxic elements support the metabolism of diverse prokaryotes by serving as respiratory electron acceptors for growth. Here, we demonstrate that two anaerobes previously shown to be capable of respiring oxyanions of selenium also achieve growth by reduction of either tellurate [Te(VI)] or tellurite [Te(IV)] to elemental tellurium [Te(0)]. This reduction achieves a sizeable stable-Te-isotopic fractionation (isotopic enrichment factor [??] = -0.4 to -1.0 per ml per atomic mass unit) and results in the formation of unique crystalline Te(0) nanoarchitectures as end products. The Te(0) crystals occur internally within but mainly externally from the cells, and each microorganism forms a distinctly different structure. Those formed by Bacillus selenitireducens initially are nanorods (???10-nm diameter by 200-nm length), which cluster together, forming larger (???1,000-nm) rosettes composed of numerous individual shards (???100-nm width by 1,000-nm length). In contrast, Sulfurospirillium barnesii forms extremely small, irregularly shaped nanospheres (diameter < 50 nm) that coalesce into larger composite aggregates. Energy-dispersive X-ray spectroscopy and selected area electron diffraction indicate that both biominerals are composed entirely of Te and are crystalline, while Raman spectroscopy confirms that they are in the elemental state. These Te biominerals have specific spectral signatures (UV-visible light, Raman) that also provide clues to their internal structures. The use of microorganisms to generate Te nanomaterials may be an alternative for bench-scale syntheses. Additionally, they may also generate products with unique properties unattainable by conventional physical/chemical methods. Copyright ?? 2007, American Society for Microbiology. All Rights Reserved.

Lasing transition at 1.06 μm emission in Nd3+ -doped borate-based tellurium calcium zinc niobium oxide glasses for high-power solid-state lasers.

PubMed

Ravi, O; Prasad, K; Jain, Rajiv; Venkataswamy, M; Chaurasia, Shivanand; Deva Prasad Raju, B

2017-08-01

The spectroscopic properties of Tellurium Calcium Zinc Niobium oxide Borate (TCZNB) glasses of composition (in mol%) 10TeO 2  + 15CaO + 5ZnO + 10 Nb 2 O 5  + (60 - x)B 2 O 3  + Nd 2 O 3 (x = 0.1, 0.5, 1.0 or 1.5 mol%) have been investigated experimentally. The three phenomenological intensity parameters Ω 2 , Ω 4, Ω 6 have been calculated using the Judd-Ofelt theory and in turn radiative properties such as radiative transition probabilities, emission cross-sections, branching ratios and radiative lifetimes have been estimated. The trend found in the JO intensity parameter is Ω 2  > Ω 6  > Ω 4 If Ω 6  > Ω 4 , the glass system is favourable for the laser emission 4 F 3 /2  →  4 I 11 /2 in the infrared (IR) wavelength. The experimental values of branching ratio of 4 F 3 /2  →  4 I 11 /2 transition indicate favourable lasing action with low threshold power. The evaluated total radiative transition probabilities (A T ), stimulated emission cross-section (σ e ) and gain bandwidth parameters (σ e  × Δλ p ) were compared with earlier reports. An energy level analysis has been carried out considering the experimental energy positions of the absorption and emission bands. Copyright © 2016 John Wiley & Sons, Ltd.

41 CFR 128-1.152 - Citation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Citation. 128-1.152 Section 128-1.152 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.1-Regulation System § 128-1.152 Citation. The JPMR will be...

41 CFR 128-1.8005 - Seismic safety standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Seismic safety standards. 128-1.8005 Section 128-1.8005 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.80-Seismic Safety Program § 128-1.8005...

41 CFR 128-1.8000 - Scope.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Scope. 128-1.8000 Section 128-1.8000 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.80-Seismic Safety Program § 128-1.8000 Scope. This subpart...

41 CFR 128-1.101 - Justice Property Management Regulations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Justice Property Management Regulations. 128-1.101 Section 128-1.101 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.1-Regulation System § 128-1...

41 CFR 128-1.105 - Authority for JPMR.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Authority for JPMR. 128-1.105 Section 128-1.105 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.1-Regulation System § 128-1.105...

41 CFR 128-1.8002 - Definitions of terms.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Definitions of terms. 128-1.8002 Section 128-1.8002 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF JUSTICE 1-INTRODUCTION 1.80-Seismic Safety Program § 128-1.8002...

7 CFR 1.28 - Petitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Petitions. 1.28 Section 1.28 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Departmental Proceedings § 1.28 Petitions. Petitions by... filed with the official that issued or is authorized to issue the rule. All such petitions will be given...

22 CFR 128.8 - Hearings.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Hearings. 128.8 Section 128.8 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS ADMINISTRATIVE PROCEDURES § 128.8 Hearings. (a) A respondent who had not filed a timely written answer is not entitled to a hearing, and the case...

22 CFR 128.8 - Hearings.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Hearings. 128.8 Section 128.8 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS ADMINISTRATIVE PROCEDURES § 128.8 Hearings. (a) A respondent who had not filed a timely written answer is not entitled to a hearing, and the case...

22 CFR 128.8 - Hearings.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Hearings. 128.8 Section 128.8 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS ADMINISTRATIVE PROCEDURES § 128.8 Hearings. (a) A respondent who had not filed a timely written answer is not entitled to a hearing, and the case...

31 CFR 128.23 - Special survey reports.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Special survey reports. 128.23... § 128.23 Special survey reports. The Secretary may prescribe special survey reports with respect to.... Notice of special survey reports will be published in accordance with § 128.1(c). ...

41 CFR 128-1.5001 - Scope of subpart.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Scope of subpart. 128-1.5001 Section 128-1.5001 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5001 Scope of subpart. This subpart sets forth general definitions of...

41 CFR 128-1.5001 - Scope of subpart.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Scope of subpart. 128-1.5001 Section 128-1.5001 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5001 Scope of subpart. This subpart sets forth general definitions of...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

22 CFR 128.2 - Administrative Law Judge.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Administrative Law Judge. 128.2 Section 128.2... § 128.2 Administrative Law Judge. The Administrative Law Judge referred to in this part is an Administrative Law Judge appointed by the Department of State. The Administrative Law Judge is authorized to...

21 CFR 133.128 - Cottage cheese.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Cottage cheese. 133.128 Section 133.128 Food and... CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.128 Cottage cheese. (a) Cottage cheese is the soft uncured cheese prepared by mixing cottage...

21 CFR 133.128 - Cottage cheese.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Cottage cheese. 133.128 Section 133.128 Food and... CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.128 Cottage cheese. (a) Cottage cheese is the soft uncured cheese prepared by mixing cottage...

31 CFR 33.128 - Periodic evaluation requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 31 Money and Finance: Treasury 1 2012-07-01 2012-07-01 false Periodic evaluation requirements. 33.128 Section 33.128 Money and Finance: Treasury Office of the Secretary of the Treasury WAIVERS FOR STATE INNOVATION § 33.128 Periodic evaluation requirements. (a) The Secretary and the Secretary of...

31 CFR 33.128 - Periodic evaluation requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Periodic evaluation requirements. 33.128 Section 33.128 Money and Finance: Treasury Office of the Secretary of the Treasury WAIVERS FOR STATE INNOVATION § 33.128 Periodic evaluation requirements. (a) The Secretary and the Secretary of...

31 CFR 33.128 - Periodic evaluation requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Periodic evaluation requirements. 33.128 Section 33.128 Money and Finance: Treasury Office of the Secretary of the Treasury WAIVERS FOR STATE INNOVATION § 33.128 Periodic evaluation requirements. (a) The Secretary and the Secretary of...

22 CFR 128.2 - Administrative Law Judge.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Administrative Law Judge. 128.2 Section 128.2... § 128.2 Administrative Law Judge. The Administrative Law Judge referred to in this part is an Administrative Law Judge appointed by the Department of State. The Administrative Law Judge is authorized to...

22 CFR 128.11 - Consent agreements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Consent agreements. 128.11 Section 128.11... § 128.11 Consent agreements. (a) The Directorate of Defense Trade Controls and the respondent may, by agreement, submit to the Administrative Law Judge a proposal for the issuance of a consent order. The...

22 CFR 128.11 - Consent agreements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Consent agreements. 128.11 Section 128.11... § 128.11 Consent agreements. (a) The Directorate of Defense Trade Controls and the respondent may, by agreement, submit to the Administrative Law Judge a proposal for the issuance of a consent order. The...

22 CFR 128.11 - Consent agreements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Consent agreements. 128.11 Section 128.11... § 128.11 Consent agreements. (a) The Directorate of Defense Trade Controls and the respondent may, by agreement, submit to the Administrative Law Judge a proposal for the issuance of a consent order. The...

34 CFR 300.125-300.128 - [Reserved

Code of Federal Regulations, 2012 CFR

2012-07-01

... 34 Education 2 2012-07-01 2012-07-01 false [Reserved] 300.125-300.128 Section 300.125-300.128 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION... CHILDREN WITH DISABILITIES State Eligibility Additional Eligibility Requirements §§ 300.125-300.128...

34 CFR 300.125-300.128 - [Reserved

Code of Federal Regulations, 2014 CFR

2014-07-01

... 34 Education 2 2014-07-01 2013-07-01 true [Reserved] 300.125-300.128 Section 300.125-300.128 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION... CHILDREN WITH DISABILITIES State Eligibility Additional Eligibility Requirements §§ 300.125-300.128...

34 CFR 300.125-300.128 - [Reserved

Code of Federal Regulations, 2013 CFR

2013-07-01

... 34 Education 2 2013-07-01 2013-07-01 false [Reserved] 300.125-300.128 Section 300.125-300.128 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION... CHILDREN WITH DISABILITIES State Eligibility Additional Eligibility Requirements §§ 300.125-300.128...

9 CFR 2.128 - Inspection for missing animals.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Inspection for missing animals. 2.128 Section 2.128 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Miscellaneous § 2.128 Inspection for missing animals. Each dealer...

9 CFR 2.128 - Inspection for missing animals.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Inspection for missing animals. 2.128 Section 2.128 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Miscellaneous § 2.128 Inspection for missing animals. Each dealer...

9 CFR 2.128 - Inspection for missing animals.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Inspection for missing animals. 2.128 Section 2.128 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Miscellaneous § 2.128 Inspection for missing animals. Each dealer...

9 CFR 2.128 - Inspection for missing animals.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Inspection for missing animals. 2.128 Section 2.128 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Miscellaneous § 2.128 Inspection for missing animals. Each dealer...

9 CFR 2.128 - Inspection for missing animals.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Inspection for missing animals. 2.128 Section 2.128 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Miscellaneous § 2.128 Inspection for missing animals. Each dealer...

22 CFR 128.8 - Hearings.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Hearings. 128.8 Section 128.8 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS ADMINISTRATIVE PROCEDURES § 128.8 Hearings. (a) A respondent who had not filed a timely written answer is not entitled to a hearing, and the case...

41 CFR 128-1.5002-5 - Personal property.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Personal property. 128-1.5002-5 Section 128-1.5002-5 Public Contracts and Property Management Federal Property Management... Personal Property Management § 128-1.5002-5 Personal property. Property of any kind or interest therein...

9 CFR 354.128 - Certification of carcasses.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Certification of carcasses. 354.128 Section 354.128 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Inspection § 354.128 Certification of carcasses. Each carcass and all parts and organs thereof which are...

27 CFR 71.128 - What constitutes record.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false What constitutes record. 71.128 Section 71.128 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Miscellaneous Record § 71.128 What constitutes record. The transcript of testimony, pleadings and exhibits, all...

27 CFR 71.128 - What constitutes record.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false What constitutes record. 71.128 Section 71.128 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Miscellaneous Record § 71.128 What constitutes record. The transcript of testimony, pleadings and exhibits, all...

29 CFR 1917.128 - Signs and marking.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Signs and marking. 1917.128 Section 1917.128 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.128 Signs and marking. (a) General. Signs required by this part shall be clearly worded and...

40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... emissions from wood products industry sources. 49.128 Section 49.128 Protection of Environment ENVIRONMENTAL... Region 10 § 49.128 Rule for limiting particulate matter emissions from wood products industry sources. (a... emitted from certain wood products industry sources operating within the Indian reservation to control...

40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... emissions from wood products industry sources. 49.128 Section 49.128 Protection of Environment ENVIRONMENTAL... Region 10 § 49.128 Rule for limiting particulate matter emissions from wood products industry sources. (a... emitted from certain wood products industry sources operating within the Indian reservation to control...

31 CFR 128.13 - Special survey reports.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Special survey reports. 128.13... Transactions and Positions § 128.13 Special survey reports. The Secretary may prescribe special survey reports... respect to such data. Notice of special survey reports will be published in accordance with § 128.1(c). ...

7 CFR 60.128 - United States country of origin.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false United States country of origin. 60.128 Section 60.128... FOR FISH AND SHELLFISH General Provisions Definitions § 60.128 United States country of origin. United...: From fish or shellfish hatched, raised, harvested, and processed in the United States, and that has not...

7 CFR 60.128 - United States country of origin.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 3 2012-01-01 2012-01-01 false United States country of origin. 60.128 Section 60.128... FOR FISH AND SHELLFISH General Provisions Definitions § 60.128 United States country of origin. United...: From fish or shellfish hatched, raised, harvested, and processed in the United States, and that has not...

41 CFR 128-48.150 - Determination of type of property.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Determination of type of property. 128-48.150 Section 128-48.150 Public Contracts and Property Management Federal Property... § 128-48.150 Determination of type of property. If a bureau is unable to determine whether the personal...

41 CFR 128-48.150 - Determination of type of property.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Determination of type of property. 128-48.150 Section 128-48.150 Public Contracts and Property Management Federal Property... § 128-48.150 Determination of type of property. If a bureau is unable to determine whether the personal...

41 CFR 128-48.150 - Determination of type of property.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Determination of type of property. 128-48.150 Section 128-48.150 Public Contracts and Property Management Federal Property... § 128-48.150 Determination of type of property. If a bureau is unable to determine whether the personal...

41 CFR 128-48.150 - Determination of type of property.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Determination of type of property. 128-48.150 Section 128-48.150 Public Contracts and Property Management Federal Property... § 128-48.150 Determination of type of property. If a bureau is unable to determine whether the personal...

41 CFR 128-48.150 - Determination of type of property.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Determination of type of property. 128-48.150 Section 128-48.150 Public Contracts and Property Management Federal Property... § 128-48.150 Determination of type of property. If a bureau is unable to determine whether the personal...

7 CFR 1.28 - Petitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 1 2013-01-01 2013-01-01 false Petitions. 1.28 Section 1.28 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Departmental Proceedings § 1.28 Petitions. Petitions by interested persons in accordance with 5 U.S.C. 553(e) for the issuance, amendment or repeal of a rule may be...

29 CFR 570.128 - Good faith defense.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Good faith defense. 570.128 Section 570.128 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR... Provisions of the Fair Labor Standards Act of 1938, as Amended Enforcement § 570.128 Good faith defense. Link...

46 CFR 128.450 - Liquid-mud systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Liquid-mud systems. 128.450 Section 128.450 Shipping...: EQUIPMENT AND SYSTEMS Design Requirements for Specific Systems § 128.450 Liquid-mud systems. (a) Liquid-mud... this chapter. (b) Tanks for oil-based liquid mud must be fitted with tank vents equipped with flame...

46 CFR 128.230 - Penetrations of hulls and watertight bulkheads-materials and pressure design.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Penetrations of hulls and watertight bulkheads-materials and pressure design. 128.230 Section 128.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... § 128.230 Penetrations of hulls and watertight bulkheads—materials and pressure design. (a) Each piping...

24 CFR 1000.128 - Is income verification required for assistance under NAHASDA?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Is income verification required for assistance under NAHASDA? 1000.128 Section 1000.128 Housing and Urban Development Regulations Relating to... § 1000.128 Is income verification required for assistance under NAHASDA? (a) Yes, the recipient must...

33 CFR 110.128c - Island of Kauai, Hawaii.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Island of Kauai, Hawaii. 110.128c Section 110.128c Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.128c Island of Kauai, Hawaii. (a) Nawiliwili Bay. The...

33 CFR 110.128b - Island of Hawaii, Hawaii.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Island of Hawaii, Hawaii. 110.128b Section 110.128b Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.128b Island of Hawaii, Hawaii. (a) Hilo Bay...

33 CFR 110.128d - Island of Oahu, Hawaii. (Datum: OHD)

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Island of Oahu, Hawaii. (Datum: OHD) 110.128d Section 110.128d Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.128d Island of Oahu, Hawaii. (Datum...

46 CFR 128.120 - Plan approval.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Plan approval. 128.120 Section 128.120 Shipping COAST... AND SYSTEMS General § 128.120 Plan approval. The plans required by subchapter F of this chapter need not be submitted if the plans required by § 127.110(d) of this subchapter have been. ...

40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... emissions from wood products industry sources. 49.128 Section 49.128 Protection of Environment ENVIRONMENTAL... Region 10 § 49.128 Rule for limiting particulate matter emissions from wood products industry sources. (a... emitted from certain wood products industry sources operating within the Indian reservation to control...

The preclinical evaluation of the dual mTORC1/2 inhibitor INK-128 as a potential anti-colorectal cancer agent

PubMed Central

Li, Chen; Cui, Jian-Feng; Chen, Min-Bin; Liu, Chao-Ying; Liu, Feng; Zhang, Qian-De; Zou, Jian; Lu, Pei-Hua

2015-01-01

The colorectal cancer is the leading contributor of cancer-related mortality. Mammalian target of rapamycin (mTOR), existing in 2 complexes (mTORC1/2), is frequently dysregulated and constitutively activated in colorectal cancers. It represents an important drug target. Here we found that INK-128, the novel ATP-competitive kinase inhibitor of mTOR, blocked both mTORC1 and mTORC2 activation in colorectal cancer cells (both primary and transformed cells). The immunoprecipitation results showed that the assembly of mTORC1 (mTOR-Raptor association) and mTORC2 (mTOR-Rictor-Sin1 association) was also disrupted by INK-128. INK-128 inhibited colorectal cancer cell growth and survival, and induced both apoptotic and non-apoptotic cancer cell death. Further, INK-128 showed no effect on Erk/MAPK activation, while MEK/Erk inhibition by MEK-162 enhanced INK-128-induced cytotoxicity in colorectal cancer cells. Meanwhile, INK-128 downregulated Fascin1 (FSCN1)/E-Cadherin expressions and inhibited HT-29 cell in vitro migration. In vivo, daily INK-128 oral administration inhibited HT-29 xenograft growth in mice, which was further enhanced by MEK-162 administration. Finally, we found that INK-128 sensitized 5-fluorouracil-(5-FU)-mediated anti-HT-29 activity in vivo and in vitro. Thus, our preclinical studies strongly suggest that INK-128 might be investigated for colorectal cancer treatment in clinical trials. PMID:25692620

Antibiofilm Activity and Synergistic Inhibition of Staphylococcus aureus Biofilms by Bactericidal Protein P128 in Combination with Antibiotics

PubMed Central

Nair, Sandhya; Desai, Srividya; Poonacha, Nethravathi; Vipra, Aradhana

2016-01-01

P128 is an antistaphylococcal protein, comprising a cell wall-degrading enzymatic region and a Staphylococcus-specific binding region, which possesses specific and potent bactericidal activity against sensitive and drug-resistant strains of Staphylococcus aureus. To explore P128's ability to kill S. aureus in a range of environments relevant to clinical infection, we investigated the anti-S. aureus activity of P128 alone and in combination with standard-of-care antibiotics on planktonic and biofilm-embedded cells. P128 was found to have potent antibiofilm activity on preformed S. aureus biofilms as detected by CFU reduction and a colorimetric minimum biofilm inhibitory concentration (MBIC) assay. Scanning electron microscopic images of biofilms formed on the surfaces of microtiter plates and on catheters showed that P128 at low concentrations could destroy the biofilm structure and lyse the cells. When it was tested in combination with antibiotics which are known to be poor inhibitors of S. aureus in biofilms, such as vancomycin, gentamicin, ciprofloxacin, linezolid, and daptomycin, P128 showed highly synergistic antibiofilm activity that resulted in much reduced MBIC values for P128 and the individual antibiotics. The synergistic effect was seen for both sensitive and resistant isolates of S. aureus. Additionally, in an in vitro mixed-biofilm model mimicking the wound infection environment, P128 was able to prevent biofilm formation by virtue of its anti-Staphylococcus activity. The potent S. aureus biofilm-inhibiting activity of P128 both alone and in combination with antibiotics is an encouraging sign for the development of P128 for treatment of complicated S. aureus infections involving biofilms. PMID:27671070

Spatial and temporal activity of the foxtail millet (Setaria italica) seed-specific promoter pF128.

PubMed

Pan, Yanlin; Ma, Xin; Liang, Hanwen; Zhao, Qian; Zhu, Dengyun; Yu, Jingjuan

2015-01-01

pF128 drives GUS specifically expressed in transgenic seeds of foxtail millet and Zea mays with higher activity than the constitutive CaMV35S promoter and the maize seed-specific 19Z promoter. Foxtail millet (Setaria italica), a member of the Poaceae family, is an important food and fodder crop in arid regions. Foxtail millet is an excellent C4 crop model owing to its small genome (~490 Mb), self-pollination and availability of a complete genome sequence. F128 was isolated from a cDNA library of foxtail millet immature seeds. Real-time PCR analysis revealed that F128 mRNA was specifically expressed in immature and mature seeds. The highest F128 mRNA level was observed 5 days after pollination and gradually decreased as the seed matured. Sequence analysis suggested that the protein encoded by F128 is likely a protease inhibitor/seed storage protein/lipid-transfer protein. The 1,053 bp 5' flanking sequence of F128 (pF128) was isolated and fused to the GUS reporter gene. The corresponding vector was then transformed into Arabidopsis thaliana, foxtail millet and Zea mays. GUS analysis revealed that pF128 drove GUS expression efficiently and specifically in the seeds of transgenic Arabidopsis, foxtail millet and Zea mays. GUS activity was also detected in Arabidopsis cotyledons. Activity of pF128 was higher than that observed for the constitutive CaMV35S promoter and the maize seed-specific 19 Zein (19Z) promoter. These results indicate that pF128 is a seed-specific promoter. Its application is expected to be of considerable value in plant genetic engineering.

Efficient Killing of Planktonic and Biofilm-Embedded Coagulase-Negative Staphylococci by Bactericidal Protein P128

PubMed Central

Poonacha, Nethravathi; Nair, Sandhya; Desai, Srividya; Tuppad, Darshan; Hiremath, Deepika; Mohan, Thulasi; Vipra, Aradhana

2017-01-01

ABSTRACT Coagulase-negative staphylococci (CoNS) are the major causative agents of foreign-body-related infections, including catheter-related bloodstream infections. Because of the involvement of biofilms, foreign-body-related infections are difficult to treat. P128, a chimeric recombinant phage-derived ectolysin, has been shown to possess bactericidal activity on strains of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). We tested the killing potential of P128 on three clinically significant species of CoNS, S. epidermidis, S. haemolyticus, and S. lugdunensis, under a variety of physiological conditions representing growing and nongrowing states. The MIC90 and minimum bactericidal concentration at which 90% of strains tested are killed (MBC90) of P128 on 62 clinical strains of CoNS were found to be 16 and 32 μg/ml (0.58 and 1.16 μM), respectively, demonstrating the bactericidal nature of P128 on CoNS strains. Serum showed a potentiating effect on P128 inhibition, as indicated by 4- to 32-fold lower MIC values observed in serum. P128 caused a rapid loss of viability in all CoNS strains tested. Persisters of CoNS that were enriched in the presence of vancomycin or daptomycin were killed by P128 at 1× the MIC in a rapid manner. Low concentrations of P128 caused a 2- to 5-log reduction in CFU in stationary-phase or poorly metabolizing CoNS cultures. P128 at low concentrations eliminated CoNS biofilms in microtiter plates and on the surface of catheters. Combinations of P128 and standard-of-care (SoC) antibiotics were highly synergistic in inhibiting growth in preformed biofilms. Potent activity on planktonic cells, persisters, and biofilms of CoNS suggests that P128 is a promising candidate for the clinical development of treatments for foreign-body-related and other CoNS infections. PMID:28559263

Regulatory mechanism of microRNA-128 in osteosarcoma tumorigenesis and evolution through targeting SASH1

PubMed Central

Li, Zi; Ni, Jiangdong; Song, Deye; Ding, Muliang

2018-01-01

Osteosarcoma, which commonly occurs in young individuals, is a type of malignant tumor of growing bones. MicroRNAs (miRNAs) have been found to be involved in various cancer-related processes. In the present study, it was reported that miRNA-128 (miR-128) was overexpressed in pathological tissues from patients with osteosarcoma. The present study investigated the possible regulatory mechanism of miR-128 on the progression of osteosarcoma and offered a foundation for clinical therapeutics in osteosarcoma. First, the expressions levels of miR-128 and its target gene, SAM and SH3 domain-containing 1 (SASH1), were measured in tissues from patients with osteosarcoma, and their correlation with osteosarcoma in terms of the pathological level were examined. The effects of miR-128 on osteosarcoma cell proliferation and apoptosis were examined, and its regulation of the expression levels of SASH1 and associated proteins was analyzed. Subsequently, the association between SASH1 and miR-128 was evaluated using a dual luciferase gene reporter assay. Finally, an in vivo xenograft tumor mouse model of osteosarcoma was established to confirm the in vitro results. The results demonstrated a higher expression of miR-128 in pathological tissues, compared with that in normal tissues. From examining the patient osteosarcoma tissues, marked correlations were found between the expression of miR-128 and that of SASH1, particularly with tumor size, invasion depth, lymph node metastasis, and tumor-node-metastasis stage. Compared with the negative control group and blank control group, the results showed that the inhibition of miR-128 led to a lower cell proliferation rate and higher apoptotic rate in MG-63 cells (P<0.05). Additionally, the expression of B-cell lymphoma 2 (Bcl-2) was downregulated in the miR-128-inhibited group, compared with that in the control group, whereas the expression levels of SASH1, Bcl-2-associated X protein and caspase-3 were upregulated in the group with miR-128 inhibition (P<0.05). SASH1 was confirmed as a direct target of miR-128 using a dual luciferase gene reporter assay. Finally, the downregulation of miR-128 was found to induce tumor suppressive effects on xenograft tumor models of osteosarcoma in mice in vivo. The results of the present study suggested that miR-128 may regulate the tumorigenesis and evolution of osteosarcoma through targeting SASH1. PMID:29805606

Regulatory mechanism of microRNA-128 in osteosarcoma tumorigenesis and evolution through targeting SASH1.

PubMed

Li, Zi; Ni, Jiangdong; Song, Deye; Ding, Muliang

2018-06-01

Osteosarcoma, which commonly occurs in young individuals, is a type of malignant tumor of growing bones. MicroRNAs (miRNAs) have been found to be involved in various cancer-related processes. In the present study, it was reported that miRNA-128 (miR-128) was overexpressed in pathological tissues from patients with osteosarcoma. The present study investigated the possible regulatory mechanism of miR-128 on the progression of osteosarcoma and offered a foundation for clinical therapeutics in osteosarcoma. First, the expressions levels of miR-128 and its target gene, SAM and SH3 domain-containing 1 (SASH1), were measured in tissues from patients with osteosarcoma, and their correlation with osteosarcoma in terms of the pathological level were examined. The effects of miR-128 on osteosarcoma cell proliferation and apoptosis were examined, and its regulation of the expression levels of SASH1 and associated proteins was analyzed. Subsequently, the association between SASH1 and miR-128 was evaluated using a dual luciferase gene reporter assay. Finally, an in vivo xenograft tumor mouse model of osteosarcoma was established to confirm the in vitro results. The results demonstrated a higher expression of miR-128 in pathological tissues, compared with that in normal tissues. From examining the patient osteosarcoma tissues, marked correlations were found between the expression of miR-128 and that of SASH1, particularly with tumor size, invasion depth, lymph node metastasis, and tumor-node-metastasis stage. Compared with the negative control group and blank control group, the results showed that the inhibition of miR-128 led to a lower cell proliferation rate and higher apoptotic rate in MG-63 cells (P<0.05). Additionally, the expression of B-cell lymphoma 2 (Bcl-2) was downregulated in the miR-128-inhibited group, compared with that in the control group, whereas the expression levels of SASH1, Bcl-2-associated X protein and caspase-3 were upregulated in the group with miR-128 inhibition (P<0.05). SASH1 was confirmed as a direct target of miR-128 using a dual luciferase gene reporter assay. Finally, the downregulation of miR-128 was found to induce tumor suppressive effects on xenograft tumor models of osteosarcoma in mice in vivo . The results of the present study suggested that miR-128 may regulate the tumorigenesis and evolution of osteosarcoma through targeting SASH1.

46 CFR 128.440 - Bilge systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Bilge systems. 128.440 Section 128.440 Shipping COAST... AND SYSTEMS Design Requirements for Specific Systems § 128.440 Bilge systems. (a) Except as provided by this section, each bilge system must comply with §§ 56.50-50 and 56.50-55 of this chapter. (b) If...

46 CFR 128.440 - Bilge systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Bilge systems. 128.440 Section 128.440 Shipping COAST... AND SYSTEMS Design Requirements for Specific Systems § 128.440 Bilge systems. (a) Except as provided by this section, each bilge system must comply with §§ 56.50-50 and 56.50-55 of this chapter. (b) If...

12 CFR 128.5 - Equal Housing Lender Poster.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 1 2014-01-01 2014-01-01 false Equal Housing Lender Poster. 128.5 Section 128... REQUIREMENTS § 128.5 Equal Housing Lender Poster. (a) Each savings association shall post and maintain one or more Equal Housing Lender Posters, the text of which is prescribed in paragraph (b) of this section, in...

12 CFR 128.5 - Equal Housing Lender Poster.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 12 Banks and Banking 1 2013-01-01 2013-01-01 false Equal Housing Lender Poster. 128.5 Section 128... REQUIREMENTS § 128.5 Equal Housing Lender Poster. (a) Each savings association shall post and maintain one or more Equal Housing Lender Posters, the text of which is prescribed in paragraph (b) of this section, in...

12 CFR 128.5 - Equal Housing Lender Poster.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 12 Banks and Banking 1 2012-01-01 2012-01-01 false Equal Housing Lender Poster. 128.5 Section 128... REQUIREMENTS § 128.5 Equal Housing Lender Poster. (a) Each savings association shall post and maintain one or more Equal Housing Lender Posters, the text of which is prescribed in paragraph (b) of this section, in...

46 CFR 128.230 - Penetrations of hulls and watertight bulkheads-materials and pressure design.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Penetrations of hulls and watertight bulkheads-materials and pressure design. 128.230 Section 128.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.230 Penetrations of hulls and...

46 CFR 128.230 - Penetrations of hulls and watertight bulkheads-materials and pressure design.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Penetrations of hulls and watertight bulkheads-materials and pressure design. 128.230 Section 128.230 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.230 Penetrations of hulls and...

46 CFR 128.310 - Fuel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fuel. 128.310 Section 128.310 Shipping COAST GUARD... Main and Auxiliary Machinery § 128.310 Fuel. (a) Except as provided by paragraph (b) of this section..., must be driven by a fuel having a flashpoint of not lower than 43 °C (110 °F) as determined by ASTM D...

46 CFR 128.310 - Fuel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Fuel. 128.310 Section 128.310 Shipping COAST GUARD... Main and Auxiliary Machinery § 128.310 Fuel. (a) OSVs of less than 6,000 GT ITC (500 GRT if GT ITC is... main propulsion or for auxiliaries, must be driven by a fuel having a flashpoint of not lower than 43...

46 CFR 128.310 - Fuel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Fuel. 128.310 Section 128.310 Shipping COAST GUARD... Main and Auxiliary Machinery § 128.310 Fuel. (a) Except as provided by paragraph (b) of this section..., must be driven by a fuel having a flashpoint of not lower than 43 °C (110 °F) as determined by ASTM D...

46 CFR 128.310 - Fuel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Fuel. 128.310 Section 128.310 Shipping COAST GUARD... Main and Auxiliary Machinery § 128.310 Fuel. (a) Except as provided by paragraph (b) of this section..., must be driven by a fuel having a flashpoint of not lower than 43 °C (110 °F) as determined by ASTM D...

46 CFR 128.310 - Fuel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Fuel. 128.310 Section 128.310 Shipping COAST GUARD... Main and Auxiliary Machinery § 128.310 Fuel. (a) Except as provided by paragraph (b) of this section..., must be driven by a fuel having a flashpoint of not lower than 43 °C (110 °F) as determined by ASTM D...

A 128 x 128 InGaAs detector array for 1.0 - 1.7 microns

NASA Technical Reports Server (NTRS)

Olsen, G.; Joshi, A.; Lange, M.; Woodruff, K.; Mykietyn, E.; Gay, D.; Ackley, D.; Erickson, G.; Ban, V.; Staller, C.

1990-01-01

A two-dimensional 128 x 128 detector array for the 1.0 - 1.7 micron spectral region has been demonstrated with indium gallium arsenide. The 30 micron square pixels had 60 micron spacing in both directions and were designed to be compatible with a 2D Reticon multiplexer. Dark currents below 100 pA, capacitance near 0.1 pF, and quantum efficiencies above 80 percent were measured. Probe maps of dark current and quantum efficiency are presented along with pixel dropout data and wafer yield which was as high as 99.89 percent (7 dropouts) in an area of 6528 pixels and 99.37 percent (103 dropouts) over an entire 128 x 128 pixel region.

Photoelectrochemical cells including chalcogenophosphate photoelectrodes

NASA Technical Reports Server (NTRS)

Reichman, B.; Byvik, C. E. (Inventor)

1984-01-01

Photoelectrochemical cells employing chalcogenophosphate (MPX3) photoelectrodes are described where M is selected from the group of transition metal series of elements beginning with scandium (atomic number 21) through germanium (atomic number 32) yttrium (atomic number 39) through antimony (atomic number 51) and lanthanum (atomic number 57) through polonium (atomic number 84); P is phosphorus; and X is selected from the chalogenide series consisting of sulfur, selenium, and tellurium. These compounds have bandgaps in the desirable range from 2.0 eV to 2.2 eV for the photoelectrolysis of water and are stable when used as photoelectrodes for the same.

Ba 2TeO: A new layered oxytelluride

DOE PAGES

Besara, T.; Ramirez, D.; Sun, J.; ...

2015-02-01

For single crystals of the new semiconducting oxytelluride phase, Ba 2TeO, we synthesized from barium oxide powder and elemental tellurium in a molten barium metal flux. Ba 2TeO crystallizes in tetragonal symmetry with space group P4/nmm (#129), a=5.0337(1) Å, c=9.9437(4) Å, Z=2. The crystals were characterized by single crystal x-ray diffraction, heat capacity and optical measurements. Moreover, the optical measurements along with electronic band structure calculations indicate semiconductor behavior with a band gap of 2.93 eV. Resistivity measurements show that Ba 2TeO is highly insulating.

Calibration of the Multi-Spectral Solar Telescope Array multilayer mirrors and XUV filters

NASA Technical Reports Server (NTRS)

Allen, Maxwell J.; Willis, Thomas D.; Kankelborg, Charles C.; O'Neal, Ray H.; Martinez-Galarce, Dennis S.; Deforest, Craig E.; Jackson, Lisa; Lindblom, Joakim; Walker, Arthur B. C., Jr.; Barbee, Troy W., Jr.

1993-01-01

The Multi-Spectral Solar Telescope Array (MSSTA), a rocket-borne solar observatory, was successfully flown in May, 1991, obtaining solar images in eight XUV and FUV bands with 12 compact multilayer telescopes. Extensive measurements have recently been carried out on the multilayer telescopes and thin film filters at the Stanford Synchrotron Radiation Laboratory. These measurements are the first high spectral resolution calibrations of the MSSTA instruments. Previous measurements and/or calculations of telescope throughputs have been confirmed with greater accuracy. Results are presented on Mo/Si multilayer bandpass changes with time and experimental potassium bromide and tellurium filters.

Kinetically Controlled Synthesis of Pt-Based One-Dimensional Hierarchically Porous Nanostructures with Large Mesopores as Highly Efficient ORR Catalysts

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

Fu, Shaofang; Zhu, Chengzhou; Song, Junhua

2016-12-28

Rational design and construction of Pt-based porous nanostructures with large mesopores have triggered significant considerations because of their high surface area and more efficient mass transport. Hydrochloric acid-induced kinetic reduction of metal precursors in the presence of soft template F-127 and hard template tellurium nanowires has been successfully demonstrated to construct one-dimensional hierarchical porous PtCu alloy nanostructures with large mesopores. Moreover, the electrochemical experiments demonstrated that the resultant PtCu hierarchically porous nanostructures with optimized composition exhibit enhanced electrocatalytic performance for oxygen reduction reaction.

Skylab M518 multipurpose furnace convection analysis

NASA Technical Reports Server (NTRS)

Bourgeois, S. V.; Spradley, L. W.

1975-01-01

An analysis was performed of the convection which existed on ground tests and during skylab processing of two experiments: vapor growth of IV-VI compounds growth of spherical crystals. A parallel analysis was also performed on Skylab experiment indium antimonide crystals because indium antimonide (InSb) was used and a free surface existed in the tellurium-doped Skylab III sample. In addition, brief analyses were also performed of the microsegregation in germanium experiment because the Skylab crystals indicated turbulent convection effects. Simple dimensional analysis calculations and a more accurate, but complex, convection computer model, were used in the analysis.

An evaluation and geochemical survey of the Farah Garan East Prospect, Southeast Asir, Kingdom of Saudi Arabia

USGS Publications Warehouse

Bookstrom, Arthur A.; El Komi, Mohamed; Christian, Ralph P.; Bazzari, Maher A.

1990-01-01

Ore minerals in outcrops, and geochemically anomalous concentrations of gold, silver, copper, lead, zinc, arsenic, antimony, and tellurium are present in carbonate-rich rocks of the hot-spring assemblage. This indicates that the ore minerals and elements were deposited originally as constituents of the hot-spring assemblage. However, exposed ore-mineral occurrences are small and sparse, and geochemical anomalies are small, irregularly distributed, and of subeconomic grade. Furthermore, weak electromagnetic anomalies do not indicate the presence of subsurface bodies of concentrated, conductive ore minerals. Therefore, no drilling is recommended.

Thermal expansion and specific heat of La1-xTexCoO3

NASA Astrophysics Data System (ADS)

Thakur, Rasna; Thakur, Rajesh K.; Gaur, N. K.

2018-05-01

We present the specific heat and thermal expansion of La1-xTexCoO3 family using Modified Rigid Ion Model (MRIM). The effect of Te doping on the thermal and cohesive properties have been studied by an atomistic approach. The Debye temperature of these perovskite materials is also predicted. The effect of Tellurium doping on lattice specific heat (C), thermal expansion (α) of La1-xTexCoO3 (x= 0.05-0.25) as a function of temperature (1K≤T≤1000K) is reported probably for the first time.

Melt-Vapor Phase Diagram of the Te-S System

NASA Astrophysics Data System (ADS)

Volodin, V. N.; Trebukhov, S. A.; Kenzhaliyev, B. K.; Nitsenko, A. V.; Burabaeva, N. M.

2018-03-01

The values of partial pressure of saturated vapor of the constituents of the Te-S system are determined from boiling points. The boundaries of the melt-vapor phase transition at atmospheric pressure and in vacuum of 2000 and 100 Pa are calculated on the basis of partial pressures. A phase diagram that includes vapor-liquid equilibrium fields whose boundaries allow us to assess the behavior of elements upon distillation fractioning is plotted. It is established that the separation of elements is possible at the first evaporation-condensation cycle. Complications can be caused by crystallization of a sulfur solid solution in tellurium.

Properties and mutation studies of a bacteriophage-derived chimeric recombinant staphylolytic protein P128

PubMed Central

Saravanan, Sanjeev Rajagopalan; Paul, Vivek Daniel; George, Shilpa; Sundarrajan, Sudarson; Kumar, Nirmal; Hebbur, Madhavi; Kumar, Naveen; Veena, Ananda; Maheshwari, Uma; Appaiah, Chemira Biddappa; Chidambaran, Muralidharan; Bhat, Anuradha Gopal; Hariharan, Sukumar; Padmanabhan, Sriram

2013-01-01

P128 is a chimeric anti-staphylococcal protein having a catalytic domain from a Staphylococcus bacteriophage K tail associated structural protein and a cell wall targeting domain from the Staphylococcus bacteriocin-lysostaphin. In this study, we disclose additional properties of P128 and compared the same with lysostaphin. While lysostaphin was found to get inactivated by heat and was inactive on its parent strain S. simulans biovar staphylolyticus, P128 was thermostable and was lytic towards S. simulans biovar staphylolyticus demonstrating a difference in their mechanism of action. Selected mutation studies of the catalytic domain of P128 showed that arginine and cysteine, at 40th and 76th positions respectively, are critical for the staphylolytic activity of P128, although these amino acids are not conserved residues. In comparison to native P128, only the R40S mutant (P301) was catalytically active on zymogram gel and had a similar secondary structure, as assessed by circular dichroism analysis and in silico modeling with similar cell binding properties. Mutation of the arginine residue at 40th position of the P128 molecule caused dramatic reduction in the Vmax (∆OD600 [mg/min]) value (nearly 270 fold) and the recombinant lysostaphin also showed lesser Vmax value (nearly 1.5 fold) in comparison to the unmodified P128 protein. The kinetic parameters such as apparent Km (Km APP) and apparent Kcat (KcatAPP) of the native P128 protein also showed significant differences in comparison to the values observed for P301 and lysostaphin. PMID:24251076

MiR-128b is down-regulated in gastric cancer and negatively regulates tumour cell viability by targeting PDK1/Akt/NF-κB axis.

PubMed

Zhang, Ling; Lei, Jun; Fang, Zi-Ling; Xiong, Jian-Ping

2016-03-01

Gastric cancer (GC) is the fourth most prevalent type of cancer worldwide, which is usually caused by the interaction between environmental and genetic factors, or epigenetic aspects. Referring to the non-coding RNAs, miR-128b has been reported to be associated with many tumour cases, and exerts distinct functions in different types of cancers. However, the function of miR-128b in GC onset and progression largely remains unknown. In the present study, we found that miR-128b expression was down-regulated in tissues from 18 GC patients and 3 carcinoma cell lines. In turn, over-expression of miR-128b suppressed GC cell proliferation, invasion and promoted apoptosis. Moreover, miR-128b was predicted to bind the 3'UTR of PDK1 gene using bioinformatic target-screening tools. Accordingly, ectopic expression of miR-128b inhibited the PDK1 expression at both transcriptional and post-transcriptional levels, and furthermore, the expression of gene tailed by the 3'UTR of PDK1 gene was significantly decreased in a dualluciferase reporter assay, suggesting that PDK1 was a direct target of miR-128b in GC cells. In the conditon of miR- 128b over-expression, we also observed spontaneous inactivation of the Akt/NF-κB signalling, implying PDK1 was a potential regulator of this pathway. In conclusion, our study shed some novel light on miR-128b-PDK1/Akt/NF-κB axis on GC progression.

MicroRNA-128 targets myostatin at coding domain sequence to regulate myoblasts in skeletal muscle development.

PubMed

Shi, Lei; Zhou, Bo; Li, Pinghua; Schinckel, Allan P; Liang, Tingting; Wang, Han; Li, Huizhi; Fu, Lingling; Chu, Qingpo; Huang, Ruihua

2015-09-01

MicroRNAs (miRNAs or miRs) play a critical role in skeletal muscle development. In a previous study we observed that miR-128 was highly expressed in skeletal muscle. However, its function in regulating skeletal muscle development is not clear. Our hypothesis was that miR-128 is involved in the regulation of the proliferation and differentiation of skeletal myoblasts. In this study, through bioinformatics analyses, we demonstrate that miR-128 specifically targeted mRNA of myostatin (MSTN), a critical inhibitor of skeletal myogenesis, at coding domain sequence (CDS) region, resulting in down-regulating of myostatin post-transcription. Overexpression of miR-128 inhibited proliferation of mouse C2C12 myoblast cells but promoted myotube formation; whereas knockdown of miR-128 had completely opposite effects. In addition, ectopic miR-128 regulated the expression of myogenic factor 5 (Myf5), myogenin (MyoG), paired box (Pax) 3 and 7. Furthermore, an inverse relationship was found between the expression of miR-128 and MSTN protein expression in vivo and in vitro. Taken together, these results reveal that there is a novel pathway in skeletal muscle development in which miR-128 regulates myostatin at CDS region to inhibit proliferation but promote differentiation of myoblast cells. Copyright © 2015 Elsevier Inc. All rights reserved.

12 CFR 12.8 - Waivers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Waivers. 12.8 Section 12.8 Banks and Banking... SECURITIES TRANSACTIONS § 12.8 Waivers. A national bank may file a written request with the OCC for waiver of one or more of the requirements set forth in §§ 12.2 through 12.7, either in whole or in part. The OCC...

33 CFR 128.300 - What is required to be in a Terminal Security Plan?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false What is required to be in a Terminal Security Plan? 128.300 Section 128.300 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... for Terminal Security § 128.300 What is required to be in a Terminal Security Plan? (a) If your...

33 CFR 128.300 - What is required to be in a Terminal Security Plan?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false What is required to be in a Terminal Security Plan? 128.300 Section 128.300 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... for Terminal Security § 128.300 What is required to be in a Terminal Security Plan? (a) If your...

33 CFR 128.300 - What is required to be in a Terminal Security Plan?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false What is required to be in a Terminal Security Plan? 128.300 Section 128.300 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... for Terminal Security § 128.300 What is required to be in a Terminal Security Plan? (a) If your...

128Xe Lifetime Measurement Using the Coulex-Plunger Technique in Inverse Kinematics

NASA Astrophysics Data System (ADS)

Konstantinopoulos, T.; Lagoyannis, A.; Harissopulos, S.; Dewald, A.; Rother, W.; Ilie, G.; Jones, P.; Rakhila, P.; Greenlees, P.; Grahn, T.; Julin, R.; Balabanski, D. L.

2008-05-01

The lifetimes of the lowest collective yrast and non-yrast states in 128Xe were measured in a Coulomb excitation experiment using the recoil distance method (RDM) in inverse kinematics. Hereby, the Cologne plunger apparatus was employed together with the JUROGAM spectrometer. Excited states in 128Xe were populated using a 128Xe beam impinging on a natFe target with E(128Xe)~525 MeV. Recoils were detected by means of an array of solar cells placed at forward angles. Recoil-gated γ-spectra were measured at different plunger distances.

miR-128 modulates chemosensitivity and invasion of prostate cancer cells through targeting ZEB1.

PubMed

Sun, Xianglun; Li, Youkong; Yu, Jie; Pei, Hong; Luo, Pengcheng; Zhang, Jie

2015-05-01

Recent reports strongly suggest the profound role of miRNAs in cancer therapeutic response and progression, including invasion and metastasis. The sensitivity to therapy and invasion is the major obstacle for successful treatment in prostate cancer. We aimed to investigate the regulative effect of miR-128/zinc-finger E-box-binding homeobox 1 axis on prostate cancer cell chemosensitivity and invasion. The miR-128 expression pattern of prostate cancer cell lines and tissues was detected by real-time reverse transcriptase-polymerase chain reaction, while the mRNA and protein expression levels of zinc-finger E-box-binding homeobox 1 were measured by real-time reverse transcriptase-polymerase chain reaction and western blot assay, respectively. Dual-luciferase reporter gene assay was used to find the direct target of miR-128. Furthermore, prostate cancer cells were treated with miR-128 mimic or zinc-finger E-box-binding homeobox 1-siRNA, and then the cells' chemosensitivity and invasion were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and transwell assay, respectively. We found miR-128 expression obviously decreased in prostate cancer tissues compared with paired normal tissues. Restored miR-128 expression sensitized prostate cancer cells to cisplatin and inhibited the invasion. Furthermore, there was an inverse expression pattern between miR-128 and zinc-finger E-box-binding homeobox 1 in prostate cancer cells and tissues, and zinc-finger E-box-binding homeobox 1 was identified as a direct target of miR-128 in prostate cancer. Knockdown of zinc-finger E-box-binding homeobox 1 expression efficiently sensitized prostate cancer cells to cisplatin and inhibited the invasion. However, ectopic zinc-finger E-box-binding homeobox 1 expression impaired the effects of miR-128 on chemosensitivity and invasion in prostate cancer cells. miR-128 functions as a potential cancer suppressor in prostate cancer progression and rational therapeutic strategies for prostate cancer would be developed based on miR-128/zinc-finger E-box-binding homeobox 1 axis. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses.

PubMed

Schambach, B T; Berrang, M E; Harrison, M A; Meinersmann, R J

2014-09-01

Immersion chilling of broiler carcasses can be a site for cross-contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as an antimicrobial but can be overcome by organic material. A proprietary chlorine stabilizer (T-128) based on phosphoric acid-propylene glycol was tested as a chill tank additive in experiments simulating commercial broiler chilling. In bench-scale experiments, 0.5% T-128 was compared with plain water (control), 50 ppm of chlorine, and the combination of 0.5% T-128 with 50 ppm of chlorine to control transfer of Salmonella and Campylobacter from inoculated wing drummettes to co-chilled uninoculated drummettes. Both chlorine and T-128 lessened cross-contamination with Salmonella (P < 0.05); T-128 and T-128 with chlorine were significantly more effective (P < 0.05) than the control or plain chlorine for control of Campylobacter. T-128 treatments were noted to have a pH of less than 4.0; an additional experiment demonstrated that the antimicrobial effect of T-128 was not due merely to a lower pH. In commercial broiler chilling, a pH close to 6.0 is preferred to maximize chlorine effectiveness, while maintaining water-holding capacity of the meat. In a set of pilot-scale experiments with T-128, a near-ideal pH of 6.3 was achieved by using tap water instead of the distilled water used in bench-scale experiments. Pilot-scale chill tanks were used to compare the combination of 0.5% T-128 and 50 ppm of chlorine with 50 ppm of plain chlorine for control of cross-contamination between whole carcasses inoculated with Salmonella and Campylobacter and co-chilled uninoculated carcasses. The T-128 treatment resulted in significantly less crosscontamination by either direct contact or water transfer with both organisms compared with plain chlorine treatment. T-128 may have use in commercial broiler processing to enhance the effectiveness of chlorine in processing water.

Psychotropic effects of Lactobacillus plantarum PS128 in early life-stressed and naïve adult mice.

PubMed

Liu, Yen-Wenn; Liu, Wei-Hsien; Wu, Chien-Chen; Juan, Yi-Chen; Wu, Yu-Chen; Tsai, Huei-Ping; Wang, Sabrina; Tsai, Ying-Chieh

2016-01-15

Ingestion of specific probiotics, namely "psychobiotics", produces psychotropic effects on behavior and affects the hypothalamic-pituitary-adrenal axis and neurochemicals in the brain. We examined the psychotropic effects of a potential psychobiotic bacterium, Lactobacillus plantarum strain PS128 (PS128), on mice subjected to early life stress (ELS) and on naïve adult mice. Behavioral tests revealed that chronic ingestion of PS128 increased the locomotor activities in both ELS and naïve adult mice in the open field test. In the elevated plus maze, PS128 significantly reduced the anxiety-like behaviors in naïve adult mice but not in the ELS mice; whereas the depression-like behaviors were reduced in ELS mice but not in naïve mice in forced swimming test and sucrose preference test. PS128 administration also reduced ELS-induced elevation of serum corticosterone under both basal and stressed states but had no effect on naïve mice. In addition, PS128 reduced inflammatory cytokine levels and increased anti-inflammatory cytokine level in the serum of ELS mice. Furthermore, the dopamine level in the prefrontal cortex (PFC) was significantly increased in PS128 treated ELS and naïve adult mice whereas serotonin (5-HT) level was increased only in the naïve adult mice. These results suggest that chronic ingestion of PS128 could ameliorate anxiety- and depression-like behaviors and modulate neurochemicals related to affective disorders. Thus PS128 shows psychotropic properties and has great potential for improving stress-related symptoms. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

An Alternative Mechanism for the Methylation of Phosphoethanolamine Catalyzed by Plasmodium falciparum Phosphoethanolamine Methyltransferase*♦

PubMed Central

Saen-oon, Suwipa; Lee, Soon Goo; Jez, Joseph M.; Guallar, Victor

2014-01-01

The phosphobase methylation pathway catalyzed by the phosphoethanolamine methyltransferase in Plasmodium falciparum (PfPMT), the malaria parasite, offers an attractive target for anti-parasitic drug development. PfPMT methylates phosphoethanolamine (pEA) to phosphocholine for use in membrane biogenesis. Quantum mechanics and molecular mechanics (QM/MM) calculations tested the proposed reaction mechanism for methylation of pEA involving the previously identified Tyr-19–His-132 dyad, which indicated an energetically unfavorable mechanism. Instead, the QM/MM calculations suggested an alternative mechanism involving Asp-128. The reaction coordinate involves the stepwise transfer of a proton to Asp-128 via a bridging water molecule followed by a typical Sn2-type methyl transfer from S-adenosylmethionine to pEA. Functional analysis of the D128A, D128E, D128Q, and D128N PfPMT mutants shows a loss of activity with pEA but not with the final substrate of the methylation pathway. X-ray crystal structures of the PfPMT-D128A mutant in complex with S-adenosylhomocysteine and either pEA or phosphocholine reveal how mutation of Asp-128 disrupts a hydrogen bond network in the active site. The combined QM/MM, biochemical, and structural studies identify a key role for Asp-128 in the initial step of the phosphobase methylation pathway in Plasmodium and provide molecular insight on the evolution of multiple activities in the active site of the PMT. PMID:25288796

An alternative mechanism for the methylation of phosphoethanolamine catalyzed by Plasmodium falciparum phosphoethanolamine methyltransferase

DOE PAGES

Saen-oon, Suwipa; Lee, Soon Goo; Jez, Joseph M.; ...

2014-10-06

Here, the phosphobase methylation pathway catalyzed by the phosphoethanolamine methyltransferase in Plasmodium falciparum (PfPMT), the malaria parasite, offers an attractive target for anti-parasitic drug development. PfPMT methylates phosphoethanolamine (pEA) to phosphocholine for use in membrane biogenesis. Quantum mechanics and molecular mechanics (QM/MM) calculations tested the proposed reaction mechanism for methylation of pEA involving the previously identified Tyr-19–His-132 dyad, which indicated an energetically unfavorable mechanism. Instead, the QM/MM calculations suggested an alternative mechanism involving Asp-128. The reaction coordinate involves the stepwise transfer of a proton to Asp-128 via a bridging water molecule followed by a typical S n2-type methyl transfer frommore » S-adenosylmethionine to pEA. Functional analysis of the D128A, D128E, D128Q, and D128N PfPMT mutants shows a loss of activity with pEA but not with the final substrate of the methylation pathway. X-ray crystal structures of the PfPMT-D128A mutant in complex with S-adenosylhomocysteine and either pEA or phosphocholine reveal how mutation of Asp-128 disrupts a hydrogen bond network in the active site. The combined QM/MM, biochemical, and structural studies identify a key role for Asp-128 in the initial step of the phosphobase methylation pathway in Plasmodium and provide molecular insight on the evolution of multiple activities in the active site of the PMT.« less

An alternative mechanism for the methylation of phosphoethanolamine catalyzed by Plasmodium falciparum phosphoethanolamine methyltransferase

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

Saen-oon, Suwipa; Lee, Soon Goo; Jez, Joseph M.

Here, the phosphobase methylation pathway catalyzed by the phosphoethanolamine methyltransferase in Plasmodium falciparum (PfPMT), the malaria parasite, offers an attractive target for anti-parasitic drug development. PfPMT methylates phosphoethanolamine (pEA) to phosphocholine for use in membrane biogenesis. Quantum mechanics and molecular mechanics (QM/MM) calculations tested the proposed reaction mechanism for methylation of pEA involving the previously identified Tyr-19–His-132 dyad, which indicated an energetically unfavorable mechanism. Instead, the QM/MM calculations suggested an alternative mechanism involving Asp-128. The reaction coordinate involves the stepwise transfer of a proton to Asp-128 via a bridging water molecule followed by a typical S n2-type methyl transfer frommore » S-adenosylmethionine to pEA. Functional analysis of the D128A, D128E, D128Q, and D128N PfPMT mutants shows a loss of activity with pEA but not with the final substrate of the methylation pathway. X-ray crystal structures of the PfPMT-D128A mutant in complex with S-adenosylhomocysteine and either pEA or phosphocholine reveal how mutation of Asp-128 disrupts a hydrogen bond network in the active site. The combined QM/MM, biochemical, and structural studies identify a key role for Asp-128 in the initial step of the phosphobase methylation pathway in Plasmodium and provide molecular insight on the evolution of multiple activities in the active site of the PMT.« less

Isolation and initial characterization of the tellurite reducing moderately halophilic bacterium, Salinicoccus sp. strain QW6.

PubMed

Amoozegar, Mohammad Ali; Ashengroph, Morahem; Malekzadeh, Feridon; Reza Razavi, Mohamad; Naddaf, Saied; Kabiri, Mahboubeh

2008-01-01

Among the 49 strains of moderately halophilic bacteria isolated from the salty environments of Iran, a Gram-positive coccus designated as strain QW6 showed high capacity in the removal of toxic oxyanions of tellurium in a wide range of culture medium factors including pH (5.5-10.5), temperature (25-45 degrees C), various salts including NaCl, KCl, and Na(2)SO(4) (0.5-4 M), selenooxyanions (2-10 mM), and at different concentrations of potassium tellurite (0.5-1 mM) under aerobic condition. Phenotypic characterization and phylogenetic analyses based on 16S rDNA sequence comparisons indicated that this strain was a member of the genus Salinicoccus. The maximum tellurite removal was exhibited in 1.5M NaCl at 35 degrees C, while the activity reduced by 53% and 47% at 25 and 45 degrees C, respectively. The optimum pH for removal activity was shown to be 7.5, with 90% and 83% reduced removal capacities at the two extreme values of 5.5 and 10, respectively. The impact of different concentrations of selenooxyanions (2-10 mM) on tellurite removal by strain QW6 was evaluated. The ability of strain QW6 in the removal of tellurite in the presence of 6mM selenite increased by 25%. The concentration of toxic potassium tellurite in the supernatant of the bacterial culture medium decreased by 99% (from 0.5 to 0.005 mM) after 6 days and the color of the medium changed to black due to the formation of less toxic elemental tellurium.

Improvement of the physical properties of ZnO/CdTe core-shell nanowire arrays by CdCl2 heat treatment for solar cells

PubMed Central

2014-01-01

CdTe is an important compound semiconductor for solar cells, and its use in nanowire-based heterostructures may become a critical requirement, owing to the potential scarcity of tellurium. The effects of the CdCl2 heat treatment are investigated on the physical properties of vertically aligned ZnO/CdTe core-shell nanowire arrays grown by combining chemical bath deposition with close space sublimation. It is found that recrystallization phenomena are induced by the CdCl2 heat treatment in the CdTe shell composed of nanograins: its crystallinity is improved while grain growth and texture randomization occur. The presence of a tellurium crystalline phase that may decorate grain boundaries is also revealed. The CdCl2 heat treatment further favors the chlorine doping of the CdTe shell with the formation of chlorine A-centers and can result in the passivation of grain boundaries. The absorption properties of ZnO/CdTe core-shell nanowire arrays are highly efficient, and more than 80% of the incident light can be absorbed in the spectral range of the solar irradiance. The resulting photovoltaic properties of solar cells made from ZnO/CdTe core-shell nanowire arrays covered with CuSCN/Au back-side contact are also improved after the CdCl2 heat treatment. However, recombination and trap phenomena are expected to operate, and the collection of the holes that are mainly photo-generated in the CdTe shell from the CuSCN/Au back-side contact is presumably identified as the main critical point in these solar cells. PMID:24910576

Dietary exposure and health risk assessment for 14 toxic and essential trace elements in Yaoundé: the Cameroonian total diet study.

PubMed

Gimou, Marie-Madeleine; Pouillot, Régis; Charrondiere, U Ruth; Noël, Laurent; Guérin, Thierry; Leblanc, Jean-Charles

2014-01-01

Dietary exposure to trace elements (aluminium, antimony, barium, cadmium, lead, nickel, vanadium, copper, manganese, molybdenum, germanium, lithium, strontium and tellurium) was assessed by the total diet study (TDS) method. Sixty-four pooled samples representing 96.5% of the diet in Yaoundé, Cameroon, were prepared "as consumed" before analysis. Consumption data were sourced from a households' budget survey. Dietary exposures were compared with health-based guidance or nutritional values and to worldwide TDS results. The health-based guidance value was exceeded by ≤ 0.2% of the study population for aluminium, antimony, barium, cadmium, nickel and vanadium. For lead, the observed 95th percentile of exposure (3.05 µg kg(-1) body weight day(-1)) equals the critical value considered by JECFA for cardiovascular effects; therefore, risk to health cannot be excluded for certain consumer groups. The population at risk of excess intake for manganese, copper, molybdenum and nickel was considered to be low (≤ 0.3%). The prevalence of inadequate intake was estimated at 5.9% for copper and was nil for molybdenum. Due to the lack of toxicological and/or nutritional consistent data to perform a risk assessment, dietary exposures to germanium, lithium, strontium and tellurium were provided as supplementary data. The food groups highest contributors to exposure were "tubers and starches" for aluminium (27%), lead (39%) and copper (26%), "cereals and cereal products" for cadmium (54%) and manganese (35%), "fruits, vegetables and oilseeds" for barium (34%), molybdenum (49%) and nickel (31%), "beverages" for antimony (27%) and "fish" for vanadium (43% - lower bound). Measures should be recommended to maintain low levels of exposure before the problem could become an important health or trade issue.

Sorption characteristics and separation of tellurium ions from aqueous solutions using nano-TiO2.

PubMed

Zhang, Lei; Zhang, Min; Guo, Xingjia; Liu, Xueyan; Kang, Pingli; Chen, Xia

2010-12-15

Titanium dioxide nanoparticles (nano-TiO(2)) were employed for the sorption of Te(IV) ions from aqueous solution. A detailed study of the process was performed by varying the sorption time, pH, and temperature. The sorption was found to be fast, equilibrium was reached within 8 min. When the concentration of Te(IV) was below 40 mg L(-1), at least 97% of tellurium was adsorbed by nano-TiO(2) in the pH range of 1-2 and 8-9. The sorbed Te(IV) ions were desorbed with 2.0 mL of 0.5 mol L(-1) NaOH. The sorption data could be well interpreted by the Langmuir model with the maximum adsorption capacity of 32.75 mg g(-1) (20 ± 0.1 °C) of Te(IV) on nano-TiO(2). The kinetics and thermodynamics of the sorption of Te(IV) onto nano-TiO(2) were also studied. The kinetic experimental data properly correlated with the second-order kinetic model (k(2)=0.0368 g mg(-1)min(-1), 293 K). The overall rate process appeared to be influenced by both boundary layer diffusion and intra-particle diffusion. The mean energy of adsorption was calculated to be 17.41 kJ mol(-1) from the Dubinin-Radushkevich (D-R) adsorption isotherm at room temperature. Moreover, the thermodynamic parameters for the sorption were estimated, and the ΔH(0) and ΔG(0) values indicated the exothermic and spontaneous nature of the sorption process, respectively. Finally, Nano-TiO(2) as sorbent was successfully applied to the separation of Te(IV) from the environmental samples with satisfactory results (recoveries >95%, relative standard deviations was 2.0%). Copyright © 2010 Elsevier B.V. All rights reserved.

Effectiveness of the Novel Herbal Medicine, KIOM-MA, and Its Bioconversion Product, KIOM-MA128, on the Treatment of Atopic Dermatitis.

PubMed

Chung, Tae Ho; Kang, Tae Jin; Cho, Won-Kyung; Im, Ga Young; Lee, Geum Seon; Yang, Min Cheol; Cho, Chang-Won; Ma, Jin Yeul

2012-01-01

This study was conducted to determine if oral administration of the novel herbal medicine, KIOM-MA, and its Lactobacillus acidophilus-fermented product, KIOM-MA128, has therapeutic properties for the treatment of atopic dermatitis (AD). Using AD-induced BALB/c mice by Ovalbumin and aluminum hydroxide, the effectiveness of KIOM-MA and KIOM-MA128 on AD was evaluated. Oral administration of KIOM-MA and KIOM-MA128 reduced major clinical signs of AD including erythema/darkening, edema/papulation, excoriations, lichenification/prurigo, and dryness. Interestingly, KIOM-MA128 more significantly improved AD-related symptoms including decrease of IgE level in the plasma as well as reduction of scratching behavior, skin severity in the AD BALB/c model. HPLC analysis showed the significant changes in the constituent patterns between KIOM-MA and KIOM-MA128. Our results suggest that both KIOM-MA and KIOM-MA128 have potential for therapeutic reagent for the treatment of AD, and further, the efficacy is significantly enhanced by L. acidophilus fermentation via increases in its indicator molecule.

Effectiveness of the Novel Herbal Medicine, KIOM-MA, and Its Bioconversion Product, KIOM-MA128, on the Treatment of Atopic Dermatitis

PubMed Central

Chung, Tae Ho; Kang, Tae Jin; Cho, Won-Kyung; Im, Ga Young; Lee, Geum Seon; Yang, Min Cheol; Cho, Chang-Won; Ma, Jin Yeul

2012-01-01

This study was conducted to determine if oral administration of the novel herbal medicine, KIOM-MA, and its Lactobacillus acidophilus-fermented product, KIOM-MA128, has therapeutic properties for the treatment of atopic dermatitis (AD). Using AD-induced BALB/c mice by Ovalbumin and aluminum hydroxide, the effectiveness of KIOM-MA and KIOM-MA128 on AD was evaluated. Oral administration of KIOM-MA and KIOM-MA128 reduced major clinical signs of AD including erythema/darkening, edema/papulation, excoriations, lichenification/prurigo, and dryness. Interestingly, KIOM-MA128 more significantly improved AD-related symptoms including decrease of IgE level in the plasma as well as reduction of scratching behavior, skin severity in the AD BALB/c model. HPLC analysis showed the significant changes in the constituent patterns between KIOM-MA and KIOM-MA128. Our results suggest that both KIOM-MA and KIOM-MA128 have potential for therapeutic reagent for the treatment of AD, and further, the efficacy is significantly enhanced by L. acidophilus fermentation via increases in its indicator molecule. PMID:22454683

Sturckow uses Cycle Ergometer on Middeck (MDDK) during STS-128

NASA Image and Video Library

2009-08-29

S128-E-006315 (29 Aug. 2009) --- Astronaut Rick Sturckow, STS-128 commander, gives a “thumbs-up” signal while exercising on a bicycle ergometer on the middeck of the Earth-orbiting Space Shuttle Discovery.

Biological Control of Apple Anthracnose by Paenibacillus polymyxa APEC128, an Antagonistic Rhizobacterium

PubMed Central

Kim, Young Soo; Balaraju, Kotnala; Jeon, Yongho

2016-01-01

The present study investigated the suppression of the disease development of anthracnose caused by Colletotrichum gloeosporioides and C. acutatum in harvested apples using an antagonistic rhizobacterium Paenibacillus polymyxa APEC128 (APEC128). Out of 30 bacterial isolates from apple rhizosphere screened for antagonistic activity, the most effective strain was APEC128 as inferred from the size of the inhibition zone. This strain showed a greater growth in brain-heart infusion (BHI) broth compared to other growth media. There was a reduction in anthracnose symptoms caused by the two fungal pathogens in harvested apples after their treatment with APEC128 in comparison with non-treated control. This effect is explained by the increased production of protease and amylase by APEC128, which might have inhibited mycelial growth. In apples treated with different APEC128 suspensions, the disease caused by C. gloeosporioides and C. acutatum was greatly suppressed (by 83.6% and 79%, respectively) in treatments with the concentration of 1 × 108 colony forming units (cfu)/ml compared to other lower dosages, suggesting that the suppression of anthracnose development on harvested apples is dose-dependent. These results indicated that APEC128 is one of the promising agents in the biocontrol of apple anthracnose, which might help to increase the shelf-life of apple fruit during the post-harvest period. PMID:27298600

Biological Control of Apple Anthracnose by Paenibacillus polymyxa APEC128, an Antagonistic Rhizobacterium.

PubMed

Kim, Young Soo; Balaraju, Kotnala; Jeon, Yongho

2016-06-01

The present study investigated the suppression of the disease development of anthracnose caused by Colletotrichum gloeosporioides and C. acutatum in harvested apples using an antagonistic rhizobacterium Paenibacillus polymyxa APEC128 (APEC128). Out of 30 bacterial isolates from apple rhizosphere screened for antagonistic activity, the most effective strain was APEC128 as inferred from the size of the inhibition zone. This strain showed a greater growth in brain-heart infusion (BHI) broth compared to other growth media. There was a reduction in anthracnose symptoms caused by the two fungal pathogens in harvested apples after their treatment with APEC128 in comparison with non-treated control. This effect is explained by the increased production of protease and amylase by APEC128, which might have inhibited mycelial growth. In apples treated with different APEC128 suspensions, the disease caused by C. gloeosporioides and C. acutatum was greatly suppressed (by 83.6% and 79%, respectively) in treatments with the concentration of 1 × 10(8) colony forming units (cfu)/ml compared to other lower dosages, suggesting that the suppression of anthracnose development on harvested apples is dose-dependent. These results indicated that APEC128 is one of the promising agents in the biocontrol of apple anthracnose, which might help to increase the shelf-life of apple fruit during the post-harvest period.

Group I-III-VI.sub.2 semiconductor films for solar cell application

DOEpatents

Basol, Bulent M.; Kapur, Vijay K.

1991-01-01

This invention relates to an improved thin film solar cell with excellent electrical and mechanical integrity. The device comprises a substrate, a Group I-III-VI.sub.2 semiconductor absorber layer and a transparent window layer. The mechanical bond between the substrate and the Group I-III-VI.sub.2 semiconductor layer is enhanced by an intermediate layer between the substrate and the Group I-III-VI.sub.2 semiconductor film being grown. The intermediate layer contains tellurium or substitutes therefor, such as Se, Sn, or Pb. The intermediate layer improves the morphology and electrical characteristics of the Group I-III-VI.sub.2 semiconductor layer.

Geological structure and prospects of noble metal ore mineralization of the Khayrkhan gabbroid massif (Western Mongolia)

NASA Astrophysics Data System (ADS)

Kurumshieva, K. R.; Gertner, I. F.; Tishin, P. A.

2017-12-01

An analysis of the distribution of noble metals in zones of sulfide mineralization makes it possible to justify the isolation of four ore-bearing horizons with a specific geochemical zonation. A rise in the gold content relative to palladium and platinum is observed from the bottom upwards along the section of the stratified series of gabbroids. The study of the mineral phases of sulphides and the noble minerals itself indicates the evolution of hydrothermal solutions, which determines the different activity and mobility of the fluid (mercury, tellurium, sulfur) and ore (copper, nickel, iron, platinum, gold and silver) components.

Camel-back band-induced power factor enhancement of thermoelectric lead-tellurium from Boltzmann transport calculations

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

Wang, X. G., E-mail: wang2006@mail.ustc.edu.cn; Wang, L., E-mail: sqtb@mail.ustc.edu.cn; Liu, J., E-mail: jingliu@mail.ustc.edu.cn

2014-03-31

Band structures of PbTe can be abnormally bended via dual-doping on both the cationic and anionic sites to form camel-back multivalley energy band structures near the band edge. As a result, additional carrier pockets and strong intervalley scattering of carriers are introduced. Boltzmann transport calculations indicate that their contradictory effects yield remarkably enhanced power factor due to the improved thermopower and almost unchanged electrical conductivity in low temperature and high carrier concentration ranges. These findings prove dual-doping-induced band bending as an effective approach to improve the thermoelectric properties of PbTe and other similar materials.

Atomic-absorption determination of rhodium in chromite concentrates

USGS Publications Warehouse

Schnepfe, M.M.; Grimaldi, F.S.

1969-01-01

Rhodium is determined in chromite concentrates by atomic absorption after concentration either by co-precipitation with tellurium formed by the reduction of tellurite with tin(II) chloride or by fire assay into a gold bead. Interelement interferences in the atomic-absorption determination are removed by buffering the solutions with lanthanum sulphate (lanthanum concentration 1%). Substantial amounts of Ag, Al, Au, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ho, Hg, K, La, Mg, Mn, Mo, Na, Ni, Pb, Te, Ti, V, Y, Zn and platinum metals can be tolerated. A lower limit of approximately 0.07 ppm Rh can be determined in a 3-g sample. ?? 1969.

Selenium, tellurium and precious metal mineralogy in Uchalinsk copper-zinc-pyritic district, the Urals

NASA Astrophysics Data System (ADS)

Vikentev, I.

2016-04-01

During processing the most of Au, Ag, Se, Te, Pb, Bi, Sb, Hg as well as notable part of Cu, Zn and Cd fail for tailings and became heavy metal pollutants. Modes of occurrence of Au, Ag, Te and Se covers two giant VMS deposits: Uchaly (intensively deformed) and Uzelginsk (altered by late hydrothermal processes) as well as middle-sized Molodezn and West Ozern deposits (nondeformed) have been studied. Mineral forms of these elements as well as their presence in disperse mode in common ore minerals (pyrite, chalcopyrite, sphalerite) have been studied using SEM, EPMA, INAA, ICP-MS and LA-ICP-MS.

GILA WILDERNESS, NEW MEXICO.

USGS Publications Warehouse

Ratte, James C.; Stotelmeyer, Ronald B.

1984-01-01

Geologic, geochemical and geophysical indicators delineated during a study of the Gila Wilderness, New Mexico indicate that there are areas of probable and substantiated mineral-resource potential for gold, silver, tellurium, molybdenum, copper, lead, zinc, and fluorite. The areas which have resource potential lie along both sides of the western and southwestern boundaries of the wilderness, and adjacent to the access corridor to the Gila Cliff Dwellings National Monument in the eastern part of the wilderness. Areas marked by geothermal springs along Turkey Creek and Middle Fork of the Gila River have a probable potential for geothermal energy. No other energy-resource potential was identified within the study area.

Anomalous concentrations of gold, silver, and other metals in the Mill Canyon area, Cortez quadrangle, Eureka and Lander Counties, Nevada

USGS Publications Warehouse

Elliott, James E.; Wells, John David

1968-01-01

The Mill Canyon area is in the eastern part of the Cortez window of the Roberts Mountains thrust belt in the Cortez quadrangle, north-central Nevada. Gold and silver ores have been mined from fissure veins in Jurassic quartz monzonite and in the bordering Wenban Limestone of Devonian age. Geochemical data show anomalies of gold, silver, lead, zinc, copper, arsenic, antimony, mercury, and tellurium. Geologic and geochemical studies indicate that a formation favorable for gold deposition, the Roberts Mountains Limestone of Silurian age, may be found at depth near the mouth of Mill Canyon.

Viscosity Measurement for Tellurium Melt

NASA Technical Reports Server (NTRS)

Lin, Bochuan; Li, Chao; Ban, Heng; Scripa, Rosalia N.; Su, Ching-Hua; Lehoczky, Sandor L.

2006-01-01

The viscosity of high temperature Te melt was measured using a new technique in which a rotating magnetic field was applied to the melt sealed in a suspended ampoule, and the torque exerted by rotating melt flow on the ampoule wall was measured. Governing equations for the coupled melt flow and ampoule torsional oscillation were solved, and the viscosity was extracted from the experimental data by numerical fitting. The computational result showed good agreement with experimental data. The melt velocity transient initiated by the rotating magnetic field reached a stable condition quickly, allowing the viscosity and electrical conductivity of the melt to be determined in a short period.

Measurement of the BB Decay Half-Life of 130Te with the NEMO-3 Detector

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

A. J. Caffrey

2011-08-01

We report results from the NEMO-3 experiment based on an exposure of 1275 days with 661 g of 130Te in the form of enriched and natural tellurium foils. The double B decay rate of 130Te is found to be greater than zero with a significance of 7.7 standard deviations and the half-life is measured to be T2v 1/2 = [7.0 +/- 0.9(stat) +/- 1.1 (syst)] x 10{sup 20} yr. This represents the most precise measurement of this half-life yet published and the first real-time observation of this decay.

Kinetically Controlled Synthesis of Pt-Based One-Dimensional Hierarchically Porous Nanostructures with Large Mesopores as Highly Efficient ORR Catalysts.

PubMed

Fu, Shaofang; Zhu, Chengzhou; Song, Junhua; Engelhard, Mark H; Xia, Haibing; Du, Dan; Lin, Yuehe

2016-12-28

Rational design and construction of Pt-based porous nanostructures with large mesopores have triggered significant considerations because of their high surface area and more efficient mass transport. Hydrochloric acid-induced kinetically controlled reduction of metal precursors in the presence of soft template F-127 and hard template tellurium nanowires has been successfully demonstrated to construct one-dimensional hierarchical porous PtCu alloy nanostructures with large mesopores. Moreover, the electrochemical experiments demonstrated that the PtCu hierarchically porous nanostructures synthesized under optimized conditions exhibit enhanced electrocatalytic performance for oxygen reduction reaction in acid media.

Influence of tellurite on lifetime for samarium doped lanthanum lead borate glass

NASA Astrophysics Data System (ADS)

Madhu, A.; Eraiah, B.

2018-04-01

Samarium substituted tellurium lanthanum lead borate glass is prepared using melt quenching technique. Luminescence spectra have been recorded upon excitation with 402 nm various transitions from 4G5/2 level, for samarium doped tellurite glasses are studied and also lifetime for all the samples exhibit single exponential behaviour of decay curve. Luminescence spectra of present glasses show quenching effect due to cross-relation channels of samarium ions. The lifetime of glass samples decrease as the tellurite concentration is decreased. So, it evidences that to attain longer lifetime for lasing material one can tune the host by selecting concentration of tellurite.

Thoracic-abdominal imaging with a novel dual-layer spectral detector CT: intra-individual comparison of image quality and radiation dose with 128-row single-energy acquisition.

PubMed

Haneder, Stefan; Siedek, Florian; Doerner, Jonas; Pahn, Gregor; Grosse Hokamp, Nils; Maintz, David; Wybranski, Christian

2018-01-01

Background A novel, multi-energy, dual-layer spectral detector computed tomography (SDCT) is commercially available now with the vendor's claim that it yields the same or better quality of polychromatic, conventional CT images like modern single-energy CT scanners without any radiation dose penalty. Purpose To intra-individually compare the quality of conventional polychromatic CT images acquired with a dual-layer spectral detector (SDCT) and the latest generation 128-row single-energy-detector (CT128) from the same manufacturer. Material and Methods Fifty patients underwent portal-venous phase, thoracic-abdominal CT scans with the SDCT and prior CT128 imaging. The SDCT scanning protocol was adapted to yield a similar estimated dose length product (DLP) as the CT128. Patient dose optimization by automatic tube current modulation and CT image reconstruction with a state-of-the-art iterative algorithm were identical on both scanners. CT image contrast-to-noise ratio (CNR) was compared between the SDCT and CT128 in different anatomic structures. Image quality and noise were assessed independently by two readers with 5-point-Likert-scales. Volume CT dose index (CTDI vol ), and DLP were recorded and normalized to 68 cm acquisition length (DLP 68 ). Results The SDCT yielded higher mean CNR values of 30.0% ± 2.0% (26.4-32.5%) in all anatomic structures ( P < 0.001) and excellent scores for qualitative parameters surpassing the CT128 (all P < 0.0001) with substantial inter-rater agreement (κ ≥ 0.801). Despite adapted scan protocols the SDCT yielded lower values for CTDI vol (-10.1 ± 12.8%), DLP (-13.1 ± 13.9%), and DLP 68 (-15.3 ± 16.9%) than the CT128 (all P < 0.0001). Conclusion The SDCT scanner yielded better CT image quality compared to the CT128 and lower radiation dose parameters.

mTOR ATP-competitive inhibitor INK128 inhibits neuroblastoma growth via blocking mTORC signaling

PubMed Central

Zhang, Huiyuan; Dou, Jun; Yu, Yang; Zhao, Yanling; Fan, Yihui; Cheng, Jin; Xu, Xin; Liu, Wei; Guan, Shan; Chen, Zhenghu; shi, Yan; Patel, Roma; Vasudevan, Sanjeev A; Zage, Peter E; Zhang, Hong; Nuchtern, Jed G; Kim, Eugene S; Fu, Songbin; Yang, Jianhua

2015-01-01

High-risk neuroblastoma often develops resistance to high-dose chemotherapy. The mTOR signaling cascade is frequently deregulated in human cancers and targeting mTOR signaling sensitizes many cancer types to chemotherapy. Here, using a panel of neuroblastoma cell lines, we found that the mTOR inhibitor INK128 showed inhibitory effects on both anchorage-dependent and independent growth of neuroblastoma cells and significantly enhanced the cytotoxic effects of doxorubicin (Dox) on these cell lines. Treatment of neuroblastoma cells with INK128 blocked the activation of downstream mTOR signaling and enhanced Dox-induced apoptosis. Moreover, INK128 was able to overcome the established chemoresistance in the LA-N-6 cell line. Using an orthotopic neuroblastoma mouse model, we found that INK128 significantly inhibited tumor growth in vivo. In conclusion, we have shown that INK128-mediated mTOR inhibition possessed substantial antitumor activity and could significantly increase the sensitivity of neuroblastoma cells to Doxorubicin therapy. Taken together, our results indicate that using INK128 can provide additional efficacy to current chemotherapeutic regimens and represent a new paradigm in restoring drug sensitivity in neuroblastoma. PMID:25425103

STS-128 patch Pathd

NASA Image and Video Library

2009-04-14

STS128-S-001 (April 2009) --- The STS-128 patch symbolizes the 17A mission and represents the hardware, people and partner nations that contribute to the flight. The Space shuttle Discovery is shown in the orbit configuration with the Multi-Purpose Logistics Module (MPLM) Leonardo in the payload bay. Earth and the International Space Station wrap around the Astronaut Office symbol reminding us of the continuous human presence in space. The names of the STS-128 crew members border the patch in an unfurled manner. Included in the names is the expedition crew member who will launch on STS-128 and remain on board ISS, replacing another Expedition crew member who will return home with STS-128. The banner also completes the Astronaut Office symbol and contains the U.S. and Swedish flags representing the countries of the STS-128 crew. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA

ISBT 128 Standard for Coding Medical Products of Human Origin

PubMed Central

Ashford, Paul; Delgado, Matthew

2017-01-01

Background ISBT 128 is an international standard for the terminology, coding, labeling, and identification of medical products of human origin (MPHO). Full implementation of ISBT 128 improves traceability, transparency, vigilance and surveillance, and interoperability. Methods ICCBBA maintains the ISBT 128 standard through the activities of a network of expert volunteers, including representatives from professional scientific societies, governments and users, to standardize and maintain MPHO identification. These individuals are organized into Technical Advisory Groups and work within a structured framework as part of a quality-controlled standards development process. Results The extensive involvement of international scientific and professional societies in the development of the standard has ensured that ISBT 128 has gained widespread recognition. The user community has developed confidence in the ability of the standard to adapt to new developments in their fields of interest. The standard is fully compatible with Single European Code requirements for tissues and cells and is utilized by many European tissue establishments. ISBT 128's flexibility and robustness has allowed for expansions into subject areas such as cellular therapy, regenerative medicine, and tissue banking. Conclusion ISBT 128 is the internationally recognized standard for coding MPHO and has gained widespread use globally throughout the past two decades. PMID:29344013

7 CFR 993.128 - Nominations for membership.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Nominations for membership. 993.128 Section 993.128 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN...

7 CFR 993.128 - Nominations for membership.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Nominations for membership. 993.128 Section 993.128 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN...

7 CFR 993.128 - Nominations for membership.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Nominations for membership. 993.128 Section 993.128 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN...

Sturckow adds STS-128 crew patch to wall in Node 1 Unity

NASA Image and Video Library

2009-09-07

S128-E-007940 (7 Sept. 2009) --- NASA astronaut Rick Sturckow, STS-128 commander, adds his crew’s patch to the growing collection, in the Unity node, of insignias representing crews who have worked on the International Space Station.

Sturckow adds STS-128 crew patch to wall in Node 1 Unity

NASA Image and Video Library

2009-09-07

S128-E-007939 (7 Sept. 2009) --- NASA astronaut Rick Sturckow, STS-128 commander, adds his crew’s patch to the growing collection, in the Unity node, of insignias representing crews who have worked on the International Space Station.