bluuebunny/crossref_metadata_2025_split huggingface dataset:
Formation of Diphosphate in the Presence of Vanadium(IV)–tpen Complex
Authors: Sato Kyouhei , Tsuge Kiyoshi , Kanamori Kan 
Published: November 2012

Abstract
The reaction of VOBr2 with N,N,N′N′-tetrakis(2-pyridylmethyl)ethylenediamine (tpen) and NaH2PO4 (2:1:2 molar ratio) in an aqueous/ethanolic solution yielded purple crystals. X-ray crystal structure analyses revealed that the purple complex was a dinuclear vanadium(IV) complex bridged by a diphosphate anion, [(VIVO)2(µ-P2O7)(µ-tpen)]·10H2O. This indicates that a condensation reaction occurred between two phosphate ions during the reaction to form a phosphate–phosphate bond. A probable mechanism is proposed for the condensation reaction of two phosphate anions.
Respiratory Symptoms and Patterns of Pulmonary Dysfunction among Roofing Fiber Cement Workers in the South of Thailand
Authors: Thepaksorn Phayong , Pongpanich Sathirakorn , Siriwong Wattasit , Chapman Robert S. , Taneepanichskul Surasak 
Published: November 2012

Respiratory Symptoms and Patterns of Pulmonary Dysfunction among Roofing Fiber Cement Workers in the South of Thailand: Phayong THEPAKSORN, et al. College of Public Health Sciences, Chulalongkorn University, Thailand—ObjectiveThis study examined the associations between respiratory symptoms and patterns of pulmonary dysfunction of 115 male roofing cement workers compared with 134 unexposed subjects.MethodsA cross‐sectional study was conducted. Environmental samplings and spirometry measurements were also collected.ResultsThe exposed workers had higher respiratory dust exposure levels (0.65 mg/m3) compared with the unexposed groups (0.32 mg/m3). The exposed group had significantly higher prevalence than the unexposed group for shortness of breath (OR=2.19). The exposed group also had higher but insignificant prevalence of chronic cough (OR=1.34), chest tightness (OR=1.64), and wheezing (OR=1.89). The ventilatory respiratory function values (FEV1 and FVC) were slightly lower for the exposed group.ConclusionAn association between higher cement dust levels and a decline in ventilatory function among roofing fiber cement workers suggests that the respiratory health of roofing cement workers should be protected through policies or work standards.
Graphene materials and devices in terahertz science and technology
Authors: Otsuji Taiichi , Boubanga Tombet Stephane Albon , Satou Akira , Fukidome Hirokazu , Suemitsu Maki , Sano Eiichi , Popov Vyacheslav , Ryzhii Maxim , Ryzhii Victor 
Published: November 2012

Abstract
Phase Transitions in Pure Plutonium
Authors: Mitchell Jeremy N. , Freibert Franz, J. , Schwartz Daniel S. 
Published: November 2012

ABSTRACTThe five solid-solid phase transformations of pure Pu are typically represented in idealized thermal expansion plots as having sharp onsets and finishes with linear expansion behavior between the transitions. These behaviors are in reality less common, and the various transitions may have bursting behavior, curved onsets and finishes, and non-linear thermal expansion. In this presentation we will review the transformation behavior of diverse set of pure Pu types. These types include zone-refined pure Pu, electro-refined pure Pu, pure Pu doped with 1000 appm Ga, and alpha-phase Pu within an as-cast 1.9 atomic. % Ga alloy.
Actinide Response under Pressure Probed by Inelastic X-ray Scattering
Authors: Rueff J.-P. 
Published: November 2012

ABSTRACTThe electronic response of actinide systems under high-pressure conditions is undoubtedly of broad scientific interest but simultaneously very difficult to qualify. We will focus here on the use of inelastic x-ray scattering and its significance for actinides research through recent examples. IXS indeed combines several advantages that turn it into a powerful probe of the electronic and valence properties of f-electron systems. Besides element and orbital selectivity, resonant IXS can overcome core-hole lifetime broadening thus providing sharper spectral features and finer details about the electronic structure. Second, non-dipolar transitions are allowed in non-resonant IXS at high momentum transfer; thus “giant dipolar” Fano-like resonances that overwhelms the electron response at the O4,5 edges can be avoided. Recent results of IXS under pressure in Am and U under pressure are presented along with perspectives for actinides research at SOLEIL synchrotron.
Influence of Carbonate on Uranium Solubility in the WIPP
Authors: Lucchini Jean-Francois , Ballard Sally , Khaing Hnin 
Published: November 2012

ABSTRACTIn the performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP), the solubility of uranium (VI) was conservatively set at 10-3 M for all expected WIPP conditions, including the potential and likely effects of carbonate complexation [1]. Under WIPP-relevant conditions, long-term experiments were performed to establish the uranium (VI) solubility limits in WIPP-simulated brine over a broad range of pCH+ values [7.5-12.5] and to evaluate the contribution of carbonate complexation and hydrolysis to uranium (VI) speciation. Data obtained in carbonate-free ERDA-6 brine, a simulated WIPP brine, were reported earlier [2]. In the absence of carbonate, uranium solubility approached 10-7 M at the expected pCH+ in the WIPP (~ 9.5). In the presence of a significant amount of carbonate (millimole levels), recent experimental results showed that uranium (VI) concentrations will not exceed 10-4M. This measured solubility limit is an order of magnitude lower than the uranium solubility value currently used in the WIPP PA [3]. A small effect of borate complexation was found in the pCH+ range [7.5-10]. At pCH+ ≥ 10, hydrolysis overwhelmed carbonate effects, and no amphoteric effect was observed.
Silicon Carbide Waveguides for Optogenetic Neural Stimulation
Authors: Register Joseph , Muller Andreas , King Justin , Weeber Edwin , Frewin Christopher L. , Saddow Stephen E. 
Published: November 2012

ABSTRACTIn this paper we present a microfabricated SiC based alternative to glass-fiber optogenetic stimulation. The glass fiber system currently used for stimulation has numerous drawbacks. First, the very presence of glass can evoke an immune response in cortical tissue that can impede the light-to-neuron optical interface. This glial scarring of brain tissue effectively lowers the spatial resolution and power output of the system. Second, the fragility of an implanted glass fiber is a problem that has yet to be fully addressed. Using SiC the proposed optical structure will address these problems by significantly lowering the amount glial scarring and astrocytic activity expressed as a result of the implant. In addition, single crystal SiC allows for a flexible device that can move with the surrounding tissue without fracturing. Finally, the current glass fibers tend be single channel devices with a single ended emitter. The proposed microfabricated device will allow for multiple channels, multiple wavelengths of stimulation, and electrical feedback on each channel improving upon the current standard.
Characterization of 3C-SiC (100) as a platform for detecting the onset of acute myocardial infarction (AMI)
Authors: Oliveros Alexandra , Guiseppi-Elie Anthony , Jaroszeski Mark , Saddow Stephen E. 
Published: November 2012

ABSTRACTIn this work we describe the characterization of anti-myoglobin immobilization on 3C-SiC (100) by means of surface modification with 3-aminopropyltriethoxysilane (APTES). Surface water contact angle measurements were used to compare the wettability of 3C-SiC (100) before (16 ±3°) and after APTES layer formation (61 ±1°). Atomic force microscopy (AFM) was used to confirm the homogenous formation of APTES and anti-myoglobin immobilization with EDC-sulfo NHS coupling. For the APTES surfaces no significant change in the surface roughness was obtained whereas with anti-myoglobin surfaces, particles on the order of ∼60 nm in diameter with a globular shape were observed.
Polymeric Nanospheres Containing Rare Earth Complexes and Colloidal Crystals with Luminescent Properties
Authors: Yang Xudong , Zhao Zixi , Shen Bowen , Lin Quan , Yang Bai 
Published: November 2012

ABSTRACTColloidal particles (CPs) have been the subject of intensive studies and have attracted increasing attention from the scientific community. In this contribution, we present the design and synthesis of luminescent colloidal crystal films. Rare earth complexes as the photoluminescent source is introduced into the polymeric nanospheres system, the diameter can be controlled by changing the polymeric reaction condition, which can act as building blocks to prepare diverse functional materials. Further, three-dimensional (3-D) colloidal crystal films with excellent fluorescent properties are fabricated by self-organization of the monodispersed polymeric nanospheres. The colloidal crystal film indicates a photonic band gap, which depends on the diameter and size-dispersing of the nanospheres building blocks. It shows potential applications in fabricating optical devices, data storage, chemical and biological sensors, and color displays.
Uncooled microbolometers with hydrogenated amorphous germanium-silicon films: Different device configurations and improvements on the thermosensing films
Authors: Moreno Mario , Torres Alfonso , Ambrosio Roberto , Rosales Pedro , Kosarev Andrey , Reyes Claudia , Zuniga Carlos , Calleja Wilfrido , de la Hidalga Wade Francisco J. , Dominguez Miguel A. 
Published: November 2012

ABSTRACTWe report our main results on the development of un-cooled microbolometers based on hydrogenated amorphous Germanium-Silicon (a-GexSiy:H) thermo-sensing films deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD). Our research has been conducted to improve both, the structure of the devices (pixels) and the performance characteristics of the amorphous Germanium-Silicon thermosensing films.Our motivation is to produce microbolometers with much better performance characteristics (larger thermal coefficient of resistance, larger conductivity and better stability) than those available in commercial microbolometer arrays, based on boron doped hydrogenated amorphous silicon (a-Si:H,B).As part of our latest research, we also report the study of what we believe is the next generation of thermosensing films based on Silicon and Geranium amorphous films with embedded nanocrystals in the amorphous matrix (polymorphous films). Those materials have several advantages over amorphous, as a lower defect density, better stability and better transport properties.
Longevity of Plutonium 238 Heat Sources
Authors: Mulford Roberta N. , Richardson Paul D. , Hickey Joseph , Chavarria Rene 
Published: November 2012

ABSTRACTPlutonium oxide heat sources are used to power space missions. The heat produced by alpha decay of the 238 isotope of Pu is converted to electricity in a thermopile, providing electricity during a substantial fraction of the 88 year half-life of the isotope. Decay of the Pu produces helium and uranium, and a fraction of the evolved helium is captured in the oxide matrix. All of the helium produced in decay can in principle be contained in the oxide lattice, where it occupies the tetrahedral sites. Some helium diffuses out at a rate that is somewhat dependent on the form and morphology of the fuel. Rates have previously been measured for oxide aged about 1 year. Current measurements on sealed heat sources as old as 34 years indicate that the rate of diffusion has changed only slightly over time. Possible mechanisms for helium release include bubble diffusion, point defect migration, agglomeration and movement of He at grain boundaries, and volume diffusion through the lattice sites. We observe primarily diffusion from site to site within the lattice, with an activation energy of 18.7 kcal/mole, independent of point defect movement, despite the rising concentration of helium in the lattice over time and the accumulation of radiation damage within the lattice. Because of the slow diffusion of helium from the fuel to the headspace, heat sources are anticipated to be stable over a long lifetime.
Synthesis of FeS2 Nano Crystals for Ink-Based Solar Cells
Authors: Ganta Lakshmi Kanth , Dhakal Tara P. , Rajendran Surya , Westgate Charles R. 
Published: November 2012

ABSTRACTAlthough pyrite (FeS2) is abundant, getting a single-phase pyrite thin film is difficult due to the coexistence of various phases of iron and sulfur in nature. We propose an ink-based process for attaining the pyrite phase of iron sulfide. This work involves degassing Iron (II) chloride in an octadecylamine solution and later reflux with addition of sulfur in diphenyl ether at 200°C. The process yielded phase-pure single crystalline pyrite nanocrystals which were later cleaned and dispersed in chloroform for uniform suspension. Thus obtained nanocrystals were deposited as thin films using drop casting and spin coating. Solar cells were fabricated using CdS as an n-type window layer in a superstrate configuration. When tested, the superstrate type FeS2 nanoparticle cell showed 0.03% with high Voc of 565 mV.
Pulmonary Toxicity of Indium Tin Oxide and Copper Indium Gallium Diselenide
Authors: Tanaka Akiyo , Hirata Miyuki , Koga Kazunori , Nakano Makiko , Omae Kazuyuki , Kiyohara Yutaka 
Published: November 2012

ABSTRACTThe aim of this review is to introduce the adverse health effects of indium compounds. This review consists of 2 parts: (1) a study of the toxic effects in indium compounds in humans, and (2) a study of the toxic effects of indium tin oxide (ITO) and copper indium gallium diselenide (CIGS) in animals.To date, 4 epidemiological surveys have been conducted of indium-handling workers in Japan, and all who were studied showed that exposure to indium compounds caused pulmonary interstitial and emphysematous changes. There were clear dose-response and dose-effect relationships between the serum indium levels and the levels of Krebs von den Lungen-6 (KL-6), which is a serological indicator of interstitial pneumonia up until 2011, 8 cases of interstitial pneumonia in Japanese indium-exposed workers, 2 cases of pulmonary alveolar proteinosis (PAP) in US indium-exposed workers, and 1 case of PAP in a Chinese indium-exposed worker have been reported.In animals studies, it has been clearly demonstrated that ITO and CIGS particles cause pulmonary toxicity and that the dissolution of ITO and CIGS particles in the lungs is considerably slow when repeated intratracheal instillations were given to experimental animals.Thus, more studies are needed on the effects of human exposure to indium compounds.
Magnetic Hardening of Mechanically Alloyed Pr2Co7
Authors: Bessais L. , Fersi R. , Cabié M. , Mliki N. 
Published: November 2012

ABSTRACTThe Pr2Co7 alloys are known to crystallize in two polymorphic forms: a hexagonal of the Ce2Ni7 type structure and a rhombohedral of the Gd2Co7 one. They were synthesized by mechanical milling and subsequent annealing in high vacuum. In this work, we focus on the structural study of these phases using X-ray diffraction and transmission electron microscopy. Also, we present the evolution of magnetic properties of these compounds vs the annealing temperature. The coercivity increases with annealing temperature reaching a maximum for TA = 800 °C. The highest is equal to 18 kOe at 293 K and 23 kOe at 10 K. The high magnetic properties observed in these nanostructured Pr2Co7 intermetallic alloys have their origin in its relatively high uniaxial magnetocrystalline anisotropy field, and in the homogeneous nanostructure developed by mechanical milling process and subsequent annealing. This high coercivity is attributed to the high anisotropy field of the Pr2Co7 phase and its nanoscale grain size. This leads to the formation of a magnetically hard Pr2Co7 phase.
Sb-Te Phase-change Nanowires by Templated Electrodeposition
Authors: Ihalawela C. A. , Cook R. E. , Lin X. M. , Wang H. H. , Chen G. 
Published: November 2012

ABSTRACTPhase-change memory materials (PCMMs) are semiconductors that exhibit rapid order-disorder transition under electrical or optical pulse excitation. Currently thin-film-based PCMMs play a dominant role in fabrication of non-volatile memory devices. In contrast, phase-change nanowires (PCNWs) have the potential to overcome future challenges such as high data density and low power consumption. Among the various methods to synthesize PCNWs, the vapor-liquid-solid method has been reported previously. In this paper, we report synthesis of Sb-Te PCNWs using a templated electrochemical method. Nanoporous anodic aluminum oxide (AAO) was used as a template for the growth of nanowires. Sb-Te PCNWs with different compositions, diameters and aspect ratios were grown inside the AAO template by electrodeposition. Composition and structure of these nanowires were characterized by energy dispersive X-ray spectroscopy, X-ray diffraction, and scanning and transmission electron microscopy. It is found that electrodeposition through nanosized channels results in materials that are quite different from those electrodeposited on unrestricted surface. The mechanism of nanowire formation inside the channels of AAO template is discussed.
Localization vs delocalization of 5f electrons in actinides: Dual nature and electron spectroscopies
Authors: Zwicknagl Gertrud 
Published: November 2012

ABSTRACTIntermetallic compounds containing actinide ions exhibit a broad spectrum of different physical phenomena at low temperatures. The latter include heavy quasiparticles, unconventional superconductivity and various forms of magnetic ordering. The complex and sometimes enigmatic properties of these compounds derive from the strong correlations among the 5f electrons. Previous model calculations suggested that the intra-atomic Hund’s rule-type correlations may lead to partial localization which is reflected e. g. in the co-existence of itinerant 5f-derived heavy quasiparticles and local magnetic excitations. The conjectured "dual nature" of 5f electrons which is closely related to the question of the 5f valence of the actinide ions is not directly probed by ground state properties and the low-energy excitations. Here we present microscopic calculations for core-level spectroscopy emphasizing the consequences of strong intra-atomic correlations of the 5f shell.
Synchrotron Topography Studies of Growth and Deformation-Induced Dislocations in 4H-SiC
Authors: Dudley M. , Wang H. , Wu F. , Byrappa S. , Shun S. , Raghothamachar B. , Sanchez E. K. , Chung G. , Hansen D. , Mueller S. G. , Loboda M. J. 
Published: November 2012

ABSTRACTSynchrotron topography studies are presented of the behavior of growth dislocations and deformation-induced dislocations in 4H-SiC single crystals. The growth dislocations include those in threading orientation with line directions approximately along c with Burgers vectors of a, c, and na+mc (where n and m are integers) while the deformation-induced dislocations include those with line directions confined to the basal plane with Burgers vectors of a and Shockley partial dislocations with Burgers vectors of 1/3<1-100> as well as those with line directions in the {1-100} prismatic planes with Burgers vectors of a. Processes leading to the nucleation of the growth dislocations are discussed as well as their deflection onto the basal plane during crystal growth in a reversible process. This latter process can lead to the conversion of segments of the deflected growth dislocations into deformation induced dislocations. In some cases this can lead to dislocation multiplication via the Hopping Frank-Read source mechanism and in others to the motion of single Shockley partial dislocations leading to Shockley stacking fault expansion. Studies are also presented of interactions between threading growth dislocations with c-component of Burger’s vector facilitated by climb processes which are mediated by interactions with non-equilibrium concentrations of vacancies. This can lead to reactions whereby complete or partial dislocation Burgers vector annihilation occurs.
Highly resolved synchrotron-based investigations related to nuclear waste disposal
Authors: Denecke Melissa A. , Borchert Manuela , Denning Robert G. , de Nolf Wout , Falkenberg Gerald , Hönig Susanne , Klinkenberg Martina , Kvashnina Kristina , Neumeier Stefan , Patommel Jens , Petersmann Tobias , Pruessmann Tim , Ritter Stephan , Schroer Christian G. , Stephan Sandra , Villanova Julie , Vitova Tonya , Wellenreuther Gerd 
Published: November 2012

ABSTRACTSynchrotron-based X-ray techniques are used increasingly to characterize actinide element speciation in heterogeneous media related to nuclear waste disposal safety. Especially techniques offering added temporal, spatial and energy resolved information are advancing our understanding of f-element physics and chemistry in general and of actinide element waste disposal in particular. Examples of investigations of uranium containing systems using both highly (energy) resolved X-ray emission spectroscopy (HRXES) techniques and spatially resolved techniques with focused X-ray beams are presented in this paper: polarization dependent partial fluorescence yield X-ray absorption near edge structure (PD-PFY-XANES) spectroscopic studies of a single Cs2UO2Cl4 crystal, which experimentally reveal a splitting of the σ, π, and δ components of the 6d valence states [1], and characterization of UO2/Mo thin films prepared on different substrates using a combination of techniques (2D and 3D micro- and nano-X-ray fluorescence, XANES and both holographic and ptychographic tomography).
Models of Mixed Metal-Oxide Interfaces for Atomistic Materials Simulations
Authors: Valone Steven M. 
Published: November 2012

ABSTRACTNuclear fuels and materials present special problems to atomistic-scale modeling. At a metal-metal-oxide interface, the metal centers are charged on the oxide side, but neutral on the metallic side. The intimate contact necessitates that atomistic models for these materials be both compatible and consistent with one another at some level. A new "fragment’’ Hamiltonian (FH) model, at the atomistic level, is presented that reduces qualitatively to existing, successful models for metals, such as the embedded atom method, and ceramics, such as the charge equilibration models. Moreover, the FH model possesses both electron hopping and fundamental gaps that appear as separate terms in a generalized embedding function. The electron hopping contributions come from both one-electron and two-electron sources. These contributions appear as a result of the FH point of view, rather than being postulated. The model obeys certain wellknown theoretical limits that come from the nonlinearity of electron hopping processes as the volume of a crystal is changed. The generalized notion of embedding entails two variables instead of one. The ability to account for multiple charge states in the cations leads to the capability within the model to distinguish the qualitative differences among metallic, ionic, and covalent bonding environments. The details of all of these energies, among with fragmentfragment interactions, combine to determine the state of the atom in the material.
Oxygen potentials of PuO2-x
Authors: Komeno Akira , Kato Masato , Hirooka Shun , Sunaoshi Takeo 
Published: November 2012

ABSTRACTOxygen potentials of PuO2-x were measured at temperatures of 1473 - 1873 K by thermo-gravimetry. The oxygen potentials were determined by in situ analysis as functions of oxygen-to-metal ratio and temperature. The measurement data were analyzed on the basis of defect chemistry and an approximate equation was derived to represent the relationship among temperature, oxygen partial pressure, and deviation x in PuO2-x.