Chen, Min-Yi; Lin, Jin-Tai; Hsu, Chia-Shuo; Chang, Chung-Kai; Chiu, Ching-Wen; Chen, Hao Ming; Chou, Pi-Tai
2018-05-01
Colloidal perovskite quantum dots represent one of the most promising materials for applications in solar cells and photoluminescences. These devices require a low density of crystal defects and a high yield of photogenerated carriers, which are difficult to realize in tin-halide perovskite because of the intrinsic instability of tin during nucleation. Here, an enhancement in the luminescent property of tin-halide perovskite nanoplates (TPNPs) that are composed of strongly coupled layered structures with the chemical formula of PEA 2 SnX 4 (PEA = C 6 H 5 (CH 2 ) 2 NH 3 , X = Br, I) is reported. TPNPs (X = I) show an emission at a wavelength of 640 nm, with high quantum yield of 6.40 ± 0.14% and full width at half maximum (FWHM) as small as 36 nm. The presence of aliphatic carboxylic acid is found to play a key role in reducing the tin perovskite defect density, which significantly improves the emission intensity and stability of TPNPs. Upon mixing iodo- and bromo- precursors, the emission wavelength is successfully tuned from 640 nm (PEA 2 SnI 4 ) to 550 nm (PEA 2 SnBr 4 ), with a corresponding emission quantum yield and FWHM of 0.16-6.40% and 36-80 nm, respectively. The results demonstrate a major advance for the emission yield and tunability of tin-halide perovskites. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Binder, Mareike; Schrenk, Claudio; Block, Theresa; Pöttgen, Rainer; Schnepf, Andreas
2018-04-26
The most fruitful synthetic route to metalloid tin clusters applies the disproportionation reaction of metastable Sn(I) halide solutions, whereby Si(SiMe₃)₃ is mostly used as the stabilizing substituent. Here, we describe the synthesis and application of the slightly modified substituent Ge(SiMe₃)₃, which can be used for the synthesis of metalloid tin clusters to give the neutral cluster Sn 10 [Ge(SiMe₃)₃]₆ as well as the charged clusters {Sn 10 [Ge(SiMe₃)₃]₅} − and {Sn 10 [Ge(SiMe₃)₃]₄} 2− . The obtained metalloid clusters are structurally similar to their Si(SiMe₃)₃ derivatives. However, differences with respect to the stability in solution are observed. Additionally, a different electronic situation for the tin atoms is realized as shown by 119m Sn Mössbauer spectroscopy, giving further insight into the different kinds of tin atoms within the metalloid cluster {Sn 10 [Ge(SiMe₃)₃]₄} 2− . The synthesis of diverse derivatives gives the opportunity to check the influence of the substituent for further investigations of metalloid tin cluster compounds.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gong, Pifu; University of the Chinese Academy of Sciences, Beijing 100049; Luo, Siyang
A new alkali tin(II) halide compound, Na{sub 3}Sn{sub 2}F{sub 6}Cl, is synthesized by hydrothermal method. This compound crystallizes trigonally in space group of R-3c (167), and processes a zero-dimensional (0D) structure consisted of Na{sup +} cations, Cl{sup −} anions and the isolated [SnF{sub 3}]{sup -} trigonal pyramids in which the stereochemically active 5s{sup 2} lone pair electrons are attached to the Sn{sup 2+} cations. Interestingly, the [SnF{sub 3}]{sup −} trigonal pyramids are parallel arranged in the a-b plane, while oppositely arranged in line with rotation along the c- axis. Moreover, the energy bandgap, thermal stability and electronic structure of Na{submore » 3}Sn{sub 2}F{sub 6}Cl are characterized and the results reveal that this compound has and indirect bandgap of 3.88 eV and is stable under 270 °C. - Graphical abstract: A zero-dimensional alkaline tin halide compound, Na{sub 3}Sn{sub 2}F{sub 6}Cl, is synthesized by hydrothermal method. Interestingly, both the anions and cations coordinating polyhedra exhibit order arranged with the [SnF{sub 3}]{sup -} trigonal pyramids rotating along the c- axis.« less
Layered structures of organic/inorganic hybrid halide perovskites
NASA Astrophysics Data System (ADS)
Huan, Tran Doan; Tuoc, Vu Ngoc; Minh, Nguyen Viet
2016-03-01
Organic-inorganic hybrid halide perovskites, in which the A cations of an ABX3 perovskite are replaced by organic cations, may be used for photovoltaic and solar thermoelectric applications. In this contribution, we systematically study three lead-free hybrid perovskites, i.e., methylammonium tin iodide CH3NH3SnI3 , ammonium tin iodide NH4SnI3 , and formamidnium tin iodide HC (NH2)2SnI3 by first-principles calculations. We find that in addition to the commonly known motif in which the corner-shared SnI6 octahedra form a three-dimensional network, these materials may also favor a two-dimensional (layered) motif formed by alternating layers of the SnI6 octahedra and the organic cations. These two motifs are nearly equal in free energy and are separated by low barriers. These layered structures features many flat electronic bands near the band edges, making their electronic structures significantly different from those of the structural phases composed of three-dimension networks of SnI6 octahedra. Furthermore, because the electronic structures of HC (NH2)2SnI3 are found to be rather similar to those of CH3NH3SnI3 , formamidnium tin iodide may also be promising for the applications of methylammonium tin iodide.
Highly Efficient Broadband Yellow Phosphor Based on Zero-Dimensional Tin Mixed-Halide Perovskite.
Zhou, Chenkun; Tian, Yu; Yuan, Zhao; Lin, Haoran; Chen, Banghao; Clark, Ronald; Dilbeck, Tristan; Zhou, Yan; Hurley, Joseph; Neu, Jennifer; Besara, Tiglet; Siegrist, Theo; Djurovich, Peter; Ma, Biwu
2017-12-27
Organic-inorganic hybrid metal halide perovskites have emerged as a highly promising class of light emitters, which can be used as phosphors for optically pumped white light-emitting diodes (WLEDs). By controlling the structural dimensionality, metal halide perovskites can exhibit tunable narrow and broadband emissions from the free-exciton and self-trapped excited states, respectively. Here, we report a highly efficient broadband yellow light emitter based on zero-dimensional tin mixed-halide perovskite (C 4 N 2 H 14 Br) 4 SnBr x I 6-x (x = 3). This rare-earth-free ionically bonded crystalline material possesses a perfect host-dopant structure, in which the light-emitting metal halide species (SnBr x I 6-x 4- , x = 3) are completely isolated from each other and embedded in the wide band gap organic matrix composed of C 4 N 2 H 14 Br - . The strongly Stokes-shifted broadband yellow emission that peaked at 582 nm from this phosphor, which is a result of excited state structural reorganization, has an extremely large full width at half-maximum of 126 nm and a high photoluminescence quantum efficiency of ∼85% at room temperature. UV-pumped WLEDs fabricated using this yellow emitter together with a commercial europium-doped barium magnesium aluminate blue phosphor (BaMgAl 10 O 17 :Eu 2+ ) can exhibit high color rendering indexes of up to 85.
Brinkmann, K.O.; Zhao, J.; Pourdavoud, N.; Becker, T.; Hu, T.; Olthof, S.; Meerholz, K.; Hoffmann, L.; Gahlmann, T.; Heiderhoff, R.; Oszajca, M. F.; Luechinger, N. A.; Rogalla, D.; Chen, Y.; Cheng, B.; Riedl, T
2017-01-01
The area of thin-film photovoltaics has been overwhelmed by organometal halide perovskites. Unfortunately, serious stability concerns arise with perovskite solar cells. For example, methyl-ammonium lead iodide is known to decompose in the presence of water and, more severely, even under inert conditions at elevated temperatures. Here, we demonstrate inverted perovskite solar cells, in which the decomposition of the perovskite is significantly mitigated even at elevated temperatures. Specifically, we introduce a bilayered electron-extraction interlayer consisting of aluminium-doped zinc oxide and tin oxide. We evidence tin oxide grown by atomic layer deposition does form an outstandingly dense gas permeation barrier that effectively hinders the ingress of moisture towards the perovskite and—more importantly—it prevents the egress of decomposition products of the perovskite. Thereby, the overall decomposition of the perovskite is significantly suppressed, leading to an outstanding device stability. PMID:28067308
Ke, Weijun; Priyanka, Pragya; Vegiraju, Sureshraju; Stoumpos, Constantinos C; Spanopoulos, Ioannis; Soe, Chan Myae Myae; Marks, Tobin J; Chen, Ming-Chou; Kanatzidis, Mercouri G
2018-01-10
Developing dopant-free hole transporting layers (HTLs) is critical in achieving high-performance and robust state-of-the-art perovskite photovoltaics, especially for the air-sensitive tin-based perovskite systems. The commonly used HTLs require hygroscopic dopants and additives for optimal performance, which adds extra cost to manufacturing and limits long-term device stability. Here we demonstrate the use of a novel tetrakis-triphenylamine (TPE) small molecule prepared by a facile synthetic route as a superior dopant-free HTL for lead-free tin-based perovskite solar cells. The best-performing tin iodide perovskite cells employing the novel mixed-cation ethylenediammonium/formamidinium with the dopant-free TPE HTL achieve a power conversion efficiency as high as 7.23%, ascribed to the HTL's suitable band alignment and excellent hole extraction/collection properties. This efficiency is one of the highest reported so far for tin halide perovskite systems, highlighting potential application of TPE HTL material in low-cost high-performance tin-based perovskite solar cells.
Weidman, Mark C.; Seitz, Michael; Stranks, Samuel D.; ...
2016-07-29
Here, colloidal perovskite nanoplatelets are a promising class of semiconductor nanomaterials-exhibiting bright luminescence, tunable and spectrally narrow absorption and emission features, strongly confined excitonic states, and facile colloidal synthesis. Here, we demonstrate the high degree of spectral tunability achievable through variation of the cation, metal, and halide composition as well as nanoplatelet thickness. We synthesize nanoplatelets of the form L 2[ABX 3] n-1BX 4, where L is an organic ligand (octylammonium, butylammonium), A is a monovalent metal or organic molecular cation (cesium, methylammonium, formamidinium), B is a divalent metal cation (lead, tin), X is a halide anion (chloride, bromide, iodide),more » and n-1 is the number of unit cells in thickness. We show that variation of n, B, and X leads to large changes in the absorption and emission energy, while variation of the A cation leads to only subtle changes but can significantly impact the nanoplatelet stability and photoluminescence quantum yield (with values over 20%). Furthermore, mixed halide nanoplatelets exhibit continuous spectral tunability over a 1.5 eV spectral range, from 2.2 to 3.7 eV. The nanoplatelets have relatively large lateral dimensions (100 nm to 1 μm), which promote self-assembly into stacked superlattice structures-the periodicity of which can be adjusted based on the nanoplatelet surface ligand length. These results demonstrate the versatility of colloidal perovskite nanoplatelets as a material platform, with tunability extending from the deep-UV, across the visible, into the near-IR. In particular, the tin-containing nanoplatelets represent a significant addition to the small but increasingly important family of lead- and cadmium-free colloidal semiconductors.« less
Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas; ...
2017-07-13
Tin and lead iodide perovskite semiconductors of the composition AMX 3, where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX 6 octahedra or by simply contracting the lattice isotropically. The former effect tendsmore » to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. In conclusion, the mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas
Tin and lead iodide perovskite semiconductors of the composition AMX 3, where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX 6 octahedra or by simply contracting the lattice isotropically. The former effect tendsmore » to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. In conclusion, the mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.« less
Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas; Conings, Bert; Babayigit, Aslihan; Boyen, Hans-Gerd; Toney, Michael F; McGehee, Michael D
2017-08-16
Tin and lead iodide perovskite semiconductors of the composition AMX 3 , where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX 6 octahedra or by simply contracting the lattice isotropically. The former effect tends to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. The mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.
Organometal halide perovskite light-emitting diodes with laminated carbon nanotube electrodes
NASA Astrophysics Data System (ADS)
Shan, Xin; Bade, Sri Ganesh R.; Geske, Thomas; Davis, Melissa; Smith, Rachel; Yu, Zhibin
2017-08-01
Organometal halide perovskite light-emitting diodes (LEDs) with laminated carbon nanotube (CNT) electrodes are reported. The LEDs have an indium tin oxide (ITO) bottom electrode, a screen printed methylammonium lead tribromide (MAPbBr3)/polymer composite thin film as the emissive layer, and laminated CNT as the top electrode. The devices can be turned on at 2.2 V, reaching a brightness of 4,960 cd m-2 and a current efficiency of 1.54 cd A-1 at 6.9 V. The greatly simplified fabrication process in this work can potentially lead to the scalable manufacturing of large size and low cost LED panels in the future.
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
Conducting tin halides with a layered organic-based perovskite structure
NASA Astrophysics Data System (ADS)
Mitzi, D. B.; Feild, C. A.; Harrison, W. T. A.; Guloy, A. M.
1994-06-01
THE discovery1 of high-temperature superconductivity in layered copper oxide perovskites has generated considerable fundamental and technological interest in this class of materials. Only a few other examples of conducting layered perovskites are known; these are also oxides such as (La1-xSrx)n+1 MnnO3n+1 (ref. 2), Lan+1NinO3n+1 (ref. 3) and Ban+1PbnO3n+1 (ref. 4), all of which exhibit a trend from semiconducting to metallic behaviour with increasing number of perovskite layers (n). We report here the synthesis of a family of organic-based layered halide perovskites, (C4H9NH3)2(CH3NH3)n-1Snnl3n+1 which show a similar transition from semiconducting to metallic behaviour with increasing n. The incorporation of an organic modulation layer between the conducting tin iodide sheets potentially provides greater flexibility for tuning the electrical properties of the perovskite sheets, and we suggest that such an approach will prove valuable for exploring the range of transport properties possible with layered perovskites.
Low-Dimensional Organic Tin Bromide Perovskites and Their Photoinduced Structural Transformation.
Zhou, Chenkun; Tian, Yu; Wang, Mingchao; Rose, Alyssa; Besara, Tiglet; Doyle, Nicholas K; Yuan, Zhao; Wang, Jamie C; Clark, Ronald; Hu, Yanyan; Siegrist, Theo; Lin, Shangchao; Ma, Biwu
2017-07-24
Hybrid organic-inorganic metal halide perovskites possess exceptional structural tunability, with three- (3D), two- (2D), one- (1D), and zero-dimensional (0D) structures on the molecular level all possible. While remarkable progress has been realized in perovskite research in recent years, the focus has been mainly on 3D and 2D structures, with 1D and 0D structures significantly underexplored. The synthesis and characterization of a series of low-dimensional organic tin bromide perovskites with 1D and 0D structures is reported. Using the same organic and inorganic components, but at different ratios and reaction conditions, both 1D (C 4 N 2 H 14 )SnBr 4 and 0D (C 4 N 2 H 14 Br) 4 SnBr 6 can be prepared in high yields. Moreover, photoinduced structural transformation from 1D to 0D was investigated experimentally and theoretically in which photodissociation of 1D metal halide chains followed by structural reorganization leads to the formation of a more thermodynamically stable 0D structure. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
B-Site Metal Cation Exchange in Halide Perovskites
Eperon, Giles E.; Ginger, David S.
2017-05-02
Here, we demonstrate exchange of the B-site metal cation in hybrid organic-inorganic halide perovskite thin films. We exchange tin in formamidinium tin triiodide (NH 2) 2SnI 3' or FASnI 3) with lead at controllable levels, forming (CH- (NH 2) 2SnI xPB 1-xI 3 alloys with partial substitution and fully converting the film to CH(NH 2) 2PbI 3 with a large excess of Pb 2+. We observe no evidence for phase segregation or bilayered films, indicating that conversion is uniform throughout the film. This facile technique provides a new way to control composition independently from the crystallization processes, allowing formation ofmore » the black phase of CH(NH 2) 2PbI 3 at much lower temperatures than those previously reported while also opening the door to new morphology-composition combinations. The surprising observation that the B-site metal cations are mobile may also provide insight into the nature of transient processes in these materials, suggesting that they may be involved in ionic conduction, and will be a critical consideration for long-term stability.« less
B-Site Metal Cation Exchange in Halide Perovskites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eperon, Giles E.; Ginger, David S.
Here, we demonstrate exchange of the B-site metal cation in hybrid organic-inorganic halide perovskite thin films. We exchange tin in formamidinium tin triiodide (NH 2) 2SnI 3' or FASnI 3) with lead at controllable levels, forming (CH- (NH 2) 2SnI xPB 1-xI 3 alloys with partial substitution and fully converting the film to CH(NH 2) 2PbI 3 with a large excess of Pb 2+. We observe no evidence for phase segregation or bilayered films, indicating that conversion is uniform throughout the film. This facile technique provides a new way to control composition independently from the crystallization processes, allowing formation ofmore » the black phase of CH(NH 2) 2PbI 3 at much lower temperatures than those previously reported while also opening the door to new morphology-composition combinations. The surprising observation that the B-site metal cations are mobile may also provide insight into the nature of transient processes in these materials, suggesting that they may be involved in ionic conduction, and will be a critical consideration for long-term stability.« less
Non-hydrolytic Sol-gel Synthesis of Tin Sulfides
NASA Astrophysics Data System (ADS)
Kaur, Rajvinder
The non-hydrolytic sol-gel (NHSG) process is an effective low temperature route well known for preparing homogeneous metal oxides. Thermodynamically as well as kinetically favored products, which cannot be prepared with the traditional solid-state routes, can be produced using NHSG. This project is focused on the exploration of NHSG synthesis of binary tin sulfides. In the past few years, metal sulfides have been the subject of significant interest. Much effort has been devoted to understand these materials because of their potential applications in electronic, optical, and superconductor devices.4 Among these materials, tin sulfides are materials of technological importance, which are being explored as semiconductors, anode materials for Li ion batteries, photoconductors, photocatalysts and absorber layer materials in photovoltaic solar cell devices. All of these applications depend upon features like homogeneity, oxidation state, high surface area and purity of the materials. These properties can be difficult to achieve by employing traditional synthetic routes, which require high temperatures due to slow diffusion, limiting the products to thermodynamically stable phases and prohibiting control over properties like particle size and surface area. A variety of low temperature methods are being explored due to the increased demand for such advanced materials. This project is focused on exploring the NHSG approach to synthesize binary tin sulfides, with the main goal of establishing conditions for the targeted synthesis of different tin sulfide polymorphs with controlled particle size. Being non-oxide materials, tin sulfides can be air sensitive, which requires special attention in handling. All reactions were carried out in absence of oxygen. This project explores the reaction of tin halides with thioethers in a dry solvent medium, leading to the formation of tin sulfides. There are a number of synthetic parameters that can be varied for the NHSG approach. A systematic study was carried out to understand the influence of all reaction variables, which include tin halides, thioethers, solvents, time, temperature, stoichiometry and concentration. Fine tuning of all reaction variables was carried out. The crystallization and phase stability of the as-recovered products was further studied by heat treatments of the samples. A detailed investigation of synthetic variables during NHSG reactions resulted in controlled synthesis of two crystalline tin sulfide polymorphs, SnS and SnS2. A third polymorph, Sn2S3, could be obtained after heat treatments in the temperature range of 400 to 500 °C. Conditions for the targeted synthesis of particles with various sizes and morphologies were established. Samples were characterized by powder X-ray diffraction, electron microscopy in combination with EDS, CHNS analysis and thermo gravimetric/differential thermal analysis.
A yield-optimized access to double-helical SnIP via a Sn/SnI2 approach
NASA Astrophysics Data System (ADS)
Utrap, André; Xiang, Ng Yan; Nilges, Tom
2017-10-01
Herein we report on the optimized synthesis process of SnIP, the first inorganic double helix compound which shows high mechanical flexibility, a strong tendency for cleavage or delamination and intriguing electronic properties. In this work we analyzed the influence of SnI2 as a reaction promotor or mineralizer compound for the synthesis of SnIP. In previous studies Sn/SnI4 was used as a precursor and chemical transport agent for the SnIP synthesis but significant amounts of non-reacted tin halide (SnI2 and SnI4) remained after the formation of the target compound reducing its quality and yield. Significantly less tin halide residue can be observed which suggests a reduction of side-reactions. While the Sn/SnI4 couple works perfectly for the synthesis of the two-dimensional material phosphorene precursor black phosphorus the Sn/SnI2 couple is beneficial for the one-dimensional ternary polyphosphide SnIP. These results strongly encourage the theory of SnI2 as the important reaction intermediate in the synthesis of covalently-bonded polyphosphide substructures and element allotropes at elevated temperatures.
Fully Printed Halide Perovskite Light-Emitting Diodes with Silver Nanowire Electrodes.
Bade, Sri Ganesh R; Li, Junqiang; Shan, Xin; Ling, Yichuan; Tian, Yu; Dilbeck, Tristan; Besara, Tiglet; Geske, Thomas; Gao, Hanwei; Ma, Biwu; Hanson, Kenneth; Siegrist, Theo; Xu, Chengying; Yu, Zhibin
2016-02-23
Printed organometal halide perovskite light-emitting diodes (LEDs) are reported that have indium tin oxide (ITO) or carbon nanotubes (CNTs) as the transparent anode, a printed composite film consisting of methylammonium lead tribromide (Br-Pero) and poly(ethylene oxide) (PEO) as the emissive layer, and printed silver nanowires as the cathode. The fabrication can be carried out in ambient air without humidity control. The devices on ITO/glass have a low turn-on voltage of 2.6 V, a maximum luminance intensity of 21014 cd m(-2), and a maximum external quantum efficiency (EQE) of 1.1%, surpassing previous reported perovskite LEDs. The devices on CNTs/polymer were able to be strained to 5 mm radius of curvature without affecting device properties.
Jung, Young-Kwang; Lee, Ji-Hwan; Walsh, Aron; Soon, Aloysius
2017-04-11
CsSnI 3 is a potential lead-free inorganic perovskite for solar energy applications due to its nontoxicity and attractive optoelectronic properties. Despite these advantages, photovoltaic cells using CsSnI 3 have not been successful to date, in part due to low stability. We demonstrate how gradual substitution of Rb for Cs influences the structural, thermodynamic, and electronic properties on the basis of first-principles density functional theory calculations. By examining the effect of the Rb:Cs ratio, we reveal a correlation between octahedral distortion and band gap, including spin-orbit coupling. We further highlight the cation-induced variation of the ionization potential (work function) and the importance of surface termination for tin-based halide perovskites for engineering high-performance solar cells.
Effect of halide-mixing on the switching behaviors of organic-inorganic hybrid perovskite memory
NASA Astrophysics Data System (ADS)
Hwang, Bohee; Gu, Chungwan; Lee, Donghwa; Lee, Jang-Sik
2017-03-01
Mixed halide perovskite materials are actively researched for solar cells with high efficiency. Their hysteresis which originates from the movement of defects make perovskite a candidate for resistive switching memory devices. We demonstrate the resistive switching device based on mixed-halide organic-inorganic hybrid perovskite CH3NH3PbI3-xBrx (x = 0, 1, 2, 3). Solvent engineering is used to deposit the homogeneous CH3NH3PbI3-xBrx layer on the indium-tin oxide-coated glass substrates. The memory device based on CH3NH3PbI3-xBrx exhibits write endurance and long retention, which indicate reproducible and reliable memory properties. According to the increase in Br contents in CH3NH3PbI3-xBrx the set electric field required to make the device from low resistance state to high resistance state decreases. This result is in accord with the theoretical calculation of migration barriers, that is the barrier to ionic migration in perovskites is found to be lower for Br- (0.23 eV) than for I- (0.29-0.30 eV). The resistive switching may be the result of halide vacancy defects and formation of conductive filaments under electric field in the mixed perovskite layer. It is observed that enhancement in operating voltage can be achieved by controlling the halide contents in the film.
NASA Astrophysics Data System (ADS)
Cao, Duyen Hanh
Halide perovskites, AMX3 (A = monocation, B = Ge, Sn, or Pb, and X = halogen), present a versatile class of solution-processable semiconductors made from earth abundant materials with outstanding electrical and optical properties. Their solar cell efficiencies have dramatically increased from 9% to 22% in less than five years since 2012, a rate that has never been seen before in photovoltaic research. Critical to the final goal of commercializing perovskite solar cell technology is achieving device long-term stability and eliminating toxic elements in device components. This thesis uses 3D AMX 3 perovskites as a stand-in to develop a new class of lead-free, moisture stable, functional and highly tunable 2D Ruddlesden-Popper (BA) 2(MA)n-1SnnI3n+1 (n is an integer) perovskite semiconductors. Synthesis, thin film fabrication, extensive characterization, and solar cell device structure-performance relationships are presented throughout the entire thesis.
Catalyzed borohydrides for hydrogen storage
Au, Ming [Augusta, GA
2012-02-28
A hydrogen storage material and process is provided in which alkali borohydride materials are created which contain effective amounts of catalyst(s) which include transition metal oxides, halides, and chlorides of titanium, zirconium, tin, and combinations of the various catalysts. When the catalysts are added to an alkali borodydride such as a lithium borohydride, the initial hydrogen release point of the resulting mixture is substantially lowered. Additionally, the hydrogen storage material may be rehydrided with weight percent values of hydrogen at least about 9 percent.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Chenkun; Lin, Haoran; Shi, Hongliang
The synthesis and characterization is reported of (C 9NH 20) 2SnBr 4, a novel organic metal halide hybrid with a zero-dimensional (0D) structure, in which individual seesaw-shaped tin (II) bromide anions (SnBr 4 2-) are co-crystallized with 1-butyl-1-methylpyrrolidinium cations (C 9NH 20 +). Upon photoexcitation, the bulk crystals exhibit a highly efficient broadband deep-red emission peaked at 695 nm, with a large Stokes shift of 332 nm and a high quantum efficiency of around 46 %. Furthermore, the unique photophysical properties of this hybrid material are attributed to two major factors: 1) the 0D structure allowing the bulk crystals tomore » exhibit the intrinsic properties of individual SnBr 4 2- species, and 2) the seesaw structure then enables a pronounced excited state structural deformation as confirmed by density functional theory (DFT) calculations.« less
Direct X-ray detection with hybrid solar cells based on organolead halide perovskites
NASA Astrophysics Data System (ADS)
Gill, Hardeep Singh; Elshahat, Bassem; Sajo, Erno; Kumar, Jayant; Kokil, Akshay; Zygmanski, Piotr; Li, Lian; Mosurkal, Ravi
2014-03-01
Organolead halide perovskite materials are attracting considerable interest due to their exceptional opto-electronic properties, such as, high charge carrier mobilities, high exciton diffusion length, high extinction coefficients and broad-band absorption. These interesting properties have enabled their application in high performance hybrid photovoltaic devices. The high Z value of their constituents also makes these materials efficient for absorbing X-rays. Here we will present on the efficient use of hybrid solar cells based on organolead perovskite materials as X-ray detectors. Hybrid solar cells based on CH3NH3PbI3 were fabricated using facile processing techniques on patterned indium tin oxide coated glass substrates. The solar cells typically had a planar configuration of ITO/CH3NH3PbI3/P3HT/Ag. High sensitivity for X-rays due to high Z value, larger carrier mobility and better charge collection was observed. Detecting X-rays with energies relevant to medical oncology applications opens up the potential for diagnostic imaging applications.
Turkevych, Ivan; Kazaoui, Said; Ito, Eisuke; Urano, Toshiyuki; Yamada, Koji; Tomiyasu, Hiroshi; Yamagishi, Hideo; Kondo, Michio; Aramaki, Shinji
2017-10-09
Hybrid CPbX 3 (C: Cs, CH 3 NH 3 ; X: Br, I) perovskites possess excellent photovoltaic properties but are highly toxic, which hinders their practical application. Unfortunately, all Pb-free alternatives based on Sn and Ge are extremely unstable. Although stable and non-toxic C 2 ABX 6 double perovskites based on alternating corner-shared AX 6 and BX 6 octahedra (A=Ag, Cu; B=Bi, Sb) are possible, they have indirect and wide band gaps of over 2 eV. However, is it necessary to keep the corner-shared perovskite structure to retain good photovoltaic properties? Here, we demonstrate another family of photovoltaic halides based on edge-shared AX 6 and BX 6 octahedra with the general formula A a B b X x (x=a+3 b) such as Ag 3 BiI 6 , Ag 2 BiI 5 , AgBiI 4 , AgBi 2 I 7 . As perovskites were named after their prototype oxide CaTiO 3 discovered by Lev Perovski, we propose to name these new ABX halides as rudorffites after Walter Rüdorff, who discovered their prototype oxide NaVO 2 . We studied structural and optoelectronic properties of several highly stable and promising Ag-Bi-I photovoltaic rudorffites that feature direct band gaps in the range of 1.79-1.83 eV and demonstrated a proof-of-concept FTO/c-m-TiO 2 /Ag 3 BiI 6 /PTAA/Au (FTO: fluorine-doped tin oxide, PTAA: poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], c: compact, m: mesoporous) solar cell with photoconversion efficiency of 4.3 %. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Use of radiation in preparative chemistry
NASA Technical Reports Server (NTRS)
Philipp, W. H.; Marksik, S. J.; May, C. E.; Lad, R. A.
1971-01-01
A summary and updating of previous work on the use of radiation chemistry for the preparation of pure materials are presented. Work was chiefly concerned with the reduction of metal salts in solution to the free metal using 2 MeV electrons. Metals deposited from aqueous solution are copper, silver, zinc, cadmium, thallium, tin, lead, antimony, iron, nickel, cobalt, and palladium. Dry organic solvents were evaluated for the deposition of metals based on a study involving deposition of antimony from soltions of antimony (III) chloride. The use of organic liquids for the preparation of anhydrous metal halides is also presented. Reaction mechanisms for both organic liquids and aqueous system are discussed.
NASA Astrophysics Data System (ADS)
Huang, Shan; Pang, Guangming; Li, Xiangkui; Li, Jianping; Pan, Hongcheng
2017-12-01
Metal-hydroxyquinoline-halogen (MqX, M = Cd, Cu; q = 8-hydroxyquinoline; X = Cl, Br, I) nanowires are synthesized via a sonochemical-assisted method. The elemental analysis (EA), inductively coupled plasma-optical emission spectroscopy (ICP-AES), and X-ray photoelectron spectroscopy (XPS) support an M/q/X ratio of 1:1:1. The electron microscope images reveal a typical CdqX and CuqX nanowire diameter of 30-50 nm and a nanowire length of 400-600 nm. In addition, the synthesis of the MqX nanowires is only observed when there is an excess of halide ions (X/q molar ratio of 3 or greater). This halide deficiency results in the formation of micrometer-sized Mq2 sheets. We demonstrated the conversion of the MqX nanowires to Mq2 micro-sheets in an ultrasonic bath of 1 M 8-Hq ethanol solutions (50%, w/ w) at 50 °C for 2 h, but not vice versa. The MqX nanowires exhibited excellent properties for photoluminescence, electrochemiluminescence (ECL), and photoelectrochemistry (PEC). The CdqBr and CdqI nanowires were coated onto a glass carbon and a fluorine-doped tin oxide glass electrode to develop the above ECL and PEC methods for the detection of H2O2 and Cu2+, respectively. In the range of 2 to 14 μM, the ECL intensity of the CdqBr nanowires was inversely proportional to the concentration of H2O2 with a detection limit of 0.26 μM. For Cu2+ sensing, the photocurrent of the CdqI nanowires exhibited a linear response to Cu2+ over the range of 2 to 16 μM of which a detection limit of 0.2 μM was observed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gou, Gaoyang; Young, Joshua; Liu, Xian
2016-09-28
Owing to its ideal semiconducting band gap and good carrier transport properties, the fully inorganic perovskite CsSnI 3 has been proposed as a visible-light absorber for photovoltaic (PV) applications. However, compared to the organic inorganic lead halide perovskite CH 3NH 3PbI 3, CsSnI 3 solar cells display very low energy conversion efficiency. In this work, we propose a potential route to improve the PV properties of CsSnI 3. Using first-principles calculations, we examine the crystal structures and electronic properties of CsSnI 3, including its structural polymorphs. Next, we purposefully order Cs and Rb cations on the A site to createmore » the double perovskite (CsRb)Sn 2I 6. We find that a stable ferroelectric polarization arises from the nontrivial coupling between polar displacements and octahedral rotations of the SnI 6 network. These ferroelectric double perovskites are predicted to have energy band gaps and carrier effective masses similar to those of CsSnI 3. More importantly, unlike nonpolar CsSnI 3, the electric polarization present in ferroelectric (CsRb)Sn 2I 6 can effectively separate the photoexcited carriers, leading to novel ferroelectric PV materials with,potentially enhanced energy conversion efficiency.« less
Impact of Interfacial Layers in Perovskite Solar Cells.
Cho, An-Na; Park, Nam-Gyu
2017-10-09
Perovskite solar cells (PCSs) are composed of organic-inorganic lead halide perovskite as the light harvester. Since the first report on a long-term-durable, 9.7 % efficient, solid-state perovskite solar cell, organic-inorganic halide perovskites have received considerable attention because of their excellent optoelectronic properties. As a result, a power conversion efficiency (PCE) exceeding 22 % was certified. Controlling the grain size, grain boundary, morphology, and defects of the perovskite layer is important for achieving high efficiency. In addition, interfacial engineering is equally or more important to further improve the PCE through better charge collection and a reduction in charge recombination. In this Review, the type of interfacial layers and their impact on photovoltaic performance are investigated for both the normal and the inverted cell architectures. Four different interfaces of fluorine-doped tin oxide (FTO)/electron-transport layer (ETL), ETL/perovskite, perovskite/hole-transport layer (HTL), and HTL/metal are classified, and their roles are investigated. The effects of interfacial engineering with organic or inorganic materials on photovoltaic performance are described in detail. Grain-boundary engineering is also included because it is related to interfacial engineering and the grain boundary in the perovskite layer plays an important role in charge conduction, recombination, and chargecarrier life time. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Whisker Formation Induced by Component and Assembly Ionic Contamination
NASA Astrophysics Data System (ADS)
Snugovsky, Polina; Meschter, Stephan; Bagheri, Zohreh; Kosiba, Eva; Romansky, Marianne; Kennedy, Jeffrey
2012-02-01
This paper describes the results of an intensive whisker formation study on Pb-free assemblies with different levels of cleanliness. Thirteen types of as-received surface-mount and pin-through-hole components were cleaned and intentionally contaminated with solutions containing chloride, sulfate, bromide, and nitrate. Then the parts were assembled on double-sided boards that were also cleaned or intentionally contaminated with three fluxes having different halide contents. The assemblies were subjected to high-temperature/high-humidity testing (85°C/85% RH). Periodic examination found that contamination triggered whisker formation on both exposed tin and solder fillets. Whisker occurrence and parameters depending on the type and level of contamination are discussed. Cross-sections were used to assess the metallurgical aspects of whisker formation and the microstructural changes occurring during corrosion.
Ke, Weijun; Zhao, Dewei; Xiao, Chuanxiao; ...
2016-08-17
Both tin oxide (SnO 2) and fullerenes have been reported as electron selective layers (ESLs) for producing efficient lead halide perovskite solar cells. Here, we report that SnO 2 and fullerenes can work cooperatively to further boost the performance of perovskite solar cells. We find that fullerenes can be redissolved during perovskite deposition, allowing ultra-thin fullerenes to be retained at the interface and some dissolved fullerenes infiltrate into perovskite grain boundaries. The SnO 2 layer blocks holes effectively; whereas, the fullerenes promote electron transfer and passivate both the SnO 2/perovskite interface and perovskite grain boundaries. With careful device optimization, themore » best-performing planar perovskite solar cell using a fullerene passivated SnO 2 ESL has achieved a steady-state efficiency of 17.75% and a power conversion efficiency of 19.12% with an open circuit voltage of 1.12 V, a short-circuit current density of 22.61 mA cm -2, and a fill factor of 75.8% when measured under reverse voltage scanning. In conclusion, we find that the partial dissolving of fullerenes during perovskite deposition is the key for fabricating high-performance perovskite solar cells based on metal oxide/fullerene ESLs.« less
Charge-transport in tin-iodide perovskite CH3NH3SnI3: origin of high conductivity.
Takahashi, Yukari; Obara, Rena; Lin, Zheng-Zhong; Takahashi, Yukihiro; Naito, Toshio; Inabe, Tamotsu; Ishibashi, Shoji; Terakura, Kiyoyuki
2011-05-28
The structural and electrical properties of a metal-halide cubic perovskite, CH(3)NH(3)SnI(3), have been examined. The band structure, obtained using first-principles calculation, reveals a well-defined band gap at the Fermi level. However, the temperature dependence of the single-crystal electrical conductivity shows metallic behavior down to low temperatures. The temperature dependence of the thermoelectric power is also metallic over the whole temperature range, and the large positive value indicates that charge transport occurs with a low concentration of hole carriers. The metallic properties of this as-grown crystal are thus suggested to result from spontaneous hole-doping in the crystallization process, rather than the semi-metal electronic structure. The present study shows that artificial hole doping indeed enhances the conductivity.
Ma, Liang; Ju, Ming-Gang; Dai, Jun; Zeng, Xiao Cheng
2018-06-21
Despite their high power conversion efficiency, the commercial applications of hybrid organic-inorganic lead (Pb) halide perovskite based solar cells are still hampered by concerns about the toxicity of Pb and the structural stability in open air. Herein, based on density-functional theory computation, we show that lead-free tin (Sn) and germanium (Ge) based two-dimensional (2D) Ruddlesden-Popper hybrid organic-inorganic perovskites with a thickness of a few unit-cells, BA2MAn-1MnI3n+1 (M = Sn or Ge, n = 2-4), possess desirable electronic, excitonic and light absorption properties, thereby showing promise for photovoltaic and/or photoelectronic applications. In particular, we show that by increasing the layer thickness of the Sn-based 2D perovskites, the bandgap can be lowered towards the optimal range (0.9-1.6 eV) for solar cells. Meanwhile, the exciton binding energy is reduced to a more optimal value. In addition, theoretical assessment indicates that the thermodynamic stability of Sn-/Ge-based 2D perovskites is notably enhanced compared to that of their 3D analogues. These features render the Sn-/Ge-based 2D hybrid perovskites with a thickness of a few tens of unit cells promising lead-free perovskites with much improved structural stabilities for photovoltaic and/or photoelectronic applications.
High-Performance Flexible Perovskite Solar Cells on Ultrathin Glass: Implications of the TCO
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dou, Benjia; Miller, Elisa M.; Christians, Jeffrey A.
For halide perovskite solar cells (PSCs) to fulfill their vast potential for combining low-cost, high efficiency, and high throughput production they must be scaled using a truly transformative method, such as roll-to-roll processing. Bringing this reality closer to fruition, the present work demonstrates flexible perovskite solar cells with 18.1% power conversion efficiency on flexible Willow Glass substrates. Here, we highlight the importance of the transparent conductive oxide (TCO) layers on device performance by studying various TCOs. And while tin-doped indium oxide (ITO) and indium zinc oxide (IZO) based PSC devices demonstrate high photovoltaic performances, aluminum-doped zinc oxide (AZO) based devicesmore » underperformed in all device parameters. Analysis of X-ray photoemission spectroscopy data shows that the stoichiometry of the perovskite film surface changes dramatically when it is fabricated on AZO, demonstrating the importance of the substrate in perovskite film formation.« less
High-Performance Flexible Perovskite Solar Cells on Ultrathin Glass: Implications of the TCO
Dou, Benjia; Miller, Elisa M.; Christians, Jeffrey A.; ...
2017-09-27
For halide perovskite solar cells (PSCs) to fulfill their vast potential for combining low-cost, high efficiency, and high throughput production they must be scaled using a truly transformative method, such as roll-to-roll processing. Bringing this reality closer to fruition, the present work demonstrates flexible perovskite solar cells with 18.1% power conversion efficiency on flexible Willow Glass substrates. Here, we highlight the importance of the transparent conductive oxide (TCO) layers on device performance by studying various TCOs. And while tin-doped indium oxide (ITO) and indium zinc oxide (IZO) based PSC devices demonstrate high photovoltaic performances, aluminum-doped zinc oxide (AZO) based devicesmore » underperformed in all device parameters. Analysis of X-ray photoemission spectroscopy data shows that the stoichiometry of the perovskite film surface changes dramatically when it is fabricated on AZO, demonstrating the importance of the substrate in perovskite film formation.« less
Lead-Free, Two-Dimensional Mixed Germanium and Tin Perovskites.
Cheng, Pengfei; Wu, Tao; Liu, Junxue; Deng, Wei-Qiao; Han, Keli
2018-05-17
Hybrid two-dimensional (2D) organic-inorganic perovskites continue to draw increased attention in view of their outstanding performance in optoelectronic devices such as solar cells and light-emitting devices. Herein, for the first time, we report the synthesis and characterization of lead-free, 2D mixed Ge-Sn halide perovskites, (PEA) 2 Ge 1- x Sn x I 4 (where PEA = C 6 H 5 CH 2 CH 2 NH 3 + ), and demonstrate that the bandgaps decrease linearly with increasing Sn content. Most importantly, among them, (PEA) 2 Ge 0.5 Sn 0.5 I 4 possesses the smallest bandgap of 1.95 eV. Density functional theory calculations confirm that Sn substitution induces a smaller bandgap and more dispersed band structure, which are desirable characteristics of light-absorbing materials. In addition, conductivity and stability of (PEA) 2 Ge 0.5 Sn 0.5 I 4 have also been assessed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liang, Yangang; Zhang, Xiaohang; Gong, Yunhui
2016-01-15
We report on fabrication of organic-inorganic perovskite thin films using a hybrid method consisting of pulsed laser deposition (PLD) of lead iodide and spin-coating of methylammonium iodide. Smooth and highly crystalline CH{sub 3}NH{sub 3}PbI{sub 3} thin films have been fabricated on silicon and glass coated substrates with fluorine doped tin oxide using this PLD-based hybrid method. Planar perovskite solar cells with an inverted structure have been successfully fabricated using the perovskite films. Because of its versatility, the PLD-based hybrid fabrication method not only provides an easy and precise control of the thickness of the perovskite thin films, but also offersmore » a straightforward platform for studying the potential feasibility in using other metal halides and organic salts for formation of the organic-inorganic perovskite structure.« less
Lin, Ching Yeh; Peh, Jessie; Coote, Michelle L
2011-03-18
The chain carrier index (CCI), defined as the ratio of the bond dissociation free energies (BDFE) of corresponding chain carrier halides and hydrides, is proposed as a measure of the thermodynamic efficiency of chain carriers for radical dehalogenation. The larger this value is relative to the corresponding value of the organic substrate, the more thermodynamically efficient the process. The chloride and bromide CCIs were evaluated at the G3(MP2)-RAD(+) level of theory for 120 different R-groups, covering a broad range of carbon-centered and noncarbon-centered species; the effects of solvent and temperature have also been studied. The broad finding from this work is that successful chain carriers generally maximize the strength of their halide (versus hydride bonds) through charge-shift bonding. As a result, the thermodynamic efficiency of a chain carrier tends to increase down the periodic table, and also with the inclusion of stronger electron donating substituents. The CCIs of carbon-centered species fall into a relatively narrow range so that, even when the CCI is maximized through inclusion of lone pair donor OMe or NMe(2) groups, the thermodynamic driving force for dehalogenation of other organic substrates is modest at best, and the process is likely to be kinetically hampered. Among the noncarbon-centered species studied, bismuth- and borane-centered compounds have some of the highest CCI values and, although their kinetics requires further optimization, these classes of compounds would be worth further investigation as tin-free radical reducing agents.
Noble metal superparticles and methods of preparation thereof
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Yugang; Hu, Yongxing
A method comprises heating an aqueous solution of colloidal silver particles. A soluble noble metal halide salt is added to the aqueous solution which undergoes a redox reaction on a surface of the silver particles to form noble metal/silver halide SPs, noble metal halide/silver halide SPs or noble metal oxide/silver halide SPs on the surface of the silver particles. The heat is maintained for a predetermined time to consume the silver particles and release the noble metal/silver halide SPs, the noble metal halide/silver halide SPs or the noble metal oxide/silver halide SPs into the aqueous solution. The aqueous solution ismore » cooled. The noble metal/silver halide SPs, the noble metal halide/silver halide SPs or noble metal oxide/silver halide SPs are separated from the aqueous solution. The method optionally includes adding a soluble halide salt to the aqueous solution.« less
Laurita, Geneva; Fabini, Douglas H.; Stoumpos, Constantinos C.; Kanatzidis, Mercouri G.
2017-01-01
Hybrid halide perovskites combine ease of preparation and relatively abundant constituent elements with fascinating photophysical properties. Descriptions of the chemical and structural drivers of the remarkable properties have often focused on the potential role of the dynamic order/disorder of the molecular A-site cations. We reveal here a key aspect of the inorganic framework that potentially impacts the electronic, thermal, and dielectric properties. The temperature evolution of the X-ray pair distribution functions of hybrid perovskites ABX3 [A+ = CH3NH3 (MA) or CH(NH2)2 (FA); B2+ = Sn or Pb; X– = Br, or I] in their cubic phases above 300 K reveals temperature-activated displacement (off-centering) of the divalent group 14 cations from their nominal, centered sites. This symmetry-lowering distortion phenomenon, previously dubbed emphanisis in the context of compounds such as PbTe, is attributed to Sn2+ and Pb2+ lone pair stereochemistry. Of the materials studied here, the largest displacements from the center of the octahedral sites are found in tin iodides, a more moderate effect is found in lead bromides, and the weakest effect is seen in lead iodides. The A-site cation appears to play a role as well, with the larger FA resulting in greater off-centering for both Sn2+ and Pb2+. Dynamic off-centering, which is concealed within the framework of traditional Bragg crystallography, is proposed to play a key role in the remarkable defect-tolerant nature of transport in these semiconductors via its effect on the polarizability of the lattice. The results suggest a novel chemical design principle for future materials discovery. PMID:28989600
Large-Grain Tin-Rich Perovskite Films for Efficient Solar Cells via Metal Alloying Technique.
Tavakoli, Mohammad Mahdi; Zakeeruddin, Shaik Mohammed; Grätzel, Michael; Fan, Zhiyong
2018-03-01
Fast research progress on lead halide perovskite solar cells has been achieved in the past a few years. However, the presence of lead (Pb) in perovskite composition as a toxic element still remains a major issue for large-scale deployment. In this work, a novel and facile technique is presented to fabricate tin (Sn)-rich perovskite film using metal precursors and an alloying technique. Herein, the perovskite films are formed as a result of the reaction between Sn/Pb binary alloy metal precursors and methylammonium iodide (MAI) vapor in a chemical vapor deposition process carried out at 185 °C. It is found that in this approach the Pb/Sn precursors are first converted to (Pb/Sn)I 2 and further reaction with MAI vapor leads to the formation of perovskite films. By using Pb-Sn eutectic alloy, perovskite films with large grain sizes up to 5 µm can be grown directly from liquid phase metal. Consequently, using an alloying technique and this unique growth mechanism, a less-toxic and efficient perovskite solar cell with a power conversion efficiency (PCE) of 14.04% is demonstrated, while pure Sn and Pb perovskite solar cells prepared in this manner yield PCEs of 4.62% and 14.21%, respectively. It is found that this alloying technique can open up a new direction to further explore different alloy systems (binary or ternary alloys) with even lower melting point. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Shift Happens. How Halide Ion Defects Influence Photoinduced Segregation in Mixed Halide Perovskites
Yoon, Seog Joon; Kuno, Masaru; Kamat, Prashant V.
2017-06-01
Minimizing photoinduced segregation in mixed halide lead perovskites is important for achieving stable photovoltaic performance. The shift in the absorption and the rate of formation of iodide- and bromide-rich regions following visible excitation of mixed halide lead perovskites is found to strongly depend on the halide ion concentration. Slower formation and recovery rates observed in halide-deficient films indicate the involvement of defect sites in influencing halide phase segregation. At higher halide concentrations (in stoichiometric excess), segregation effects become less prominent, as evidenced by faster recovery kinetics. These results suggest that light-induced compositional segregation can be minimized in mixed halide perovskitemore » films by using excess halide ions. In conclusion, the findings from this study further reflect the importance of halide ion post-treatment of perovskite films to improve their solar cell performance.« less
Hybrid Lead Halide Layered Perovskites with Silsesquioxane Interlayers.
Kataoka, Sho; Kaburagi, Wako; Mochizuki, Hiroyuki; Kamimura, Yoshihiro; Sato, Kazuhiko; Endo, Akira
2018-01-01
Hybrid organic-lead halide perovskites exhibit remarkable properties as semiconductors and light absorbers. Here, we report the formation of silsesquioxane-lead halide hybrid layered perovskites. We prepared silsesquioxane with a cubic cage-like structure and fabricated hybrid silsesquioxane-lead halide layered perovskites in a self-assembled manner. It is demonstrated that the silsesquioxane maintain their cage-like structure between lead halide perovskite layers. The silsesquioxane-lead halide perovskites also show excitonic absorption and emission in the visible light region similar to typical lead halide layered perovskites.
Development of Perovskite-Type Materials for Thermoelectric Application.
Wu, Tingjun; Gao, Peng
2018-06-12
Oxide perovskite materials have a long history of being investigated for thermoelectric applications. Compared to the state-of-the-art tin and lead chalcogenides, these perovskite compounds have advantages of low toxicity, eco-friendliness, and high elemental abundance. However, because of low electrical conductivity and high thermal conductivity, the total thermoelectric performance of oxide perovskites is relatively poor. Variety of methods were used to enhance the TE properties of oxide perovskite materials, such as doping, inducing oxygen vacancy, embedding crystal imperfection, and so on. Recently, hybrid perovskite materials started to draw attention for thermoelectric application. Due to the low thermal conductivity and high Seebeck coefficient feature of hybrid perovskites materials, they can be promising thermoelectric materials and hold the potential for the application of wearable energy generators and cooling devices. This mini-review will build a bridge between oxide perovskites and burgeoning hybrid halide perovskites in the research of thermoelectric properties with an aim to further enhance the relevant performance of perovskite-type materials.
Assessing the toxicity of Pb- and Sn-based perovskite solar cells in model organism Danio rerio
NASA Astrophysics Data System (ADS)
Babayigit, Aslihan; Duy Thanh, Dinh; Ethirajan, Anitha; Manca, Jean; Muller, Marc; Boyen, Hans-Gerd; Conings, Bert
2016-01-01
Intensive development of organometal halide perovskite solar cells has lead to a dramatic surge in power conversion efficiency up to 20%. Unfortunately, the most efficient perovskite solar cells all contain lead (Pb), which is an unsettling flaw that leads to severe environmental concerns and is therefore a stumbling block envisioning their large-scale application. Aiming for the retention of favorable electro-optical properties, tin (Sn) has been considered the most likely substitute. Preliminary studies have however shown that Sn-based perovskites are highly unstable and, moreover, Sn is also enlisted as a harmful chemical, with similar concerns regarding environment and health. To bring more clarity into the appropriateness of both metals in perovskite solar cells, we provide a case study with systematic comparison regarding the environmental impact of Pb- and Sn-based perovskites, using zebrafish (Danio Rerio) as model organism. Uncovering an unexpected route of intoxication in the form of acidification, it is shown that Sn based perovskite may not be the ideal Pb surrogate.
Enhancing the Photovoltaic Performance of Perovskite Solar Cells with a Down-Conversion Eu-Complex.
Jiang, Ling; Chen, Wangchao; Zheng, Jiawei; Zhu, Liangzheng; Mo, Li'e; Li, Zhaoqian; Hu, Linhua; Hayat, Tasawar; Alsaedi, Ahmed; Zhang, Changneng; Dai, Songyuan
2017-08-16
Organometal halide perovskite solar cells (PSCs) have shown high photovoltaic performance but poor utilization of ultraviolet (UV) irradiation. Lanthanide complexes have a wide absorption range in the UV region and they can down-convert the absorbed UV light into visible light, which provides a possibility for PSCs to utilize UV light for higher photocurrent, efficiency, and stability. In this study, we use a transparent luminescent down-converting layer (LDL) of Eu-4,7-diphenyl-1,10-phenanthroline (Eu-complex) to improve the light utilization efficiency of PSCs. Compared with the uncoated PSC, the PSC coated with Eu-complex LDL on the reverse of the fluorine-doped tin oxide glass displayed an enhancement of 11.8% in short-circuit current density (J sc ) and 15.3% in efficiency due to the Eu-complex LDL re-emitting UV light (300-380 nm) in the visible range. It is indicated that the Eu-complex LDL plays the role of enhancing the power conversion efficiency as well as reducing UV degradation for PSCs.
23.6%-efficient monolithic perovskite/silicon tandem solar cells with improved stability
NASA Astrophysics Data System (ADS)
Bush, Kevin A.; Palmstrom, Axel F.; Yu, Zhengshan J.; Boccard, Mathieu; Cheacharoen, Rongrong; Mailoa, Jonathan P.; McMeekin, David P.; Hoye, Robert L. Z.; Bailie, Colin D.; Leijtens, Tomas; Peters, Ian Marius; Minichetti, Maxmillian C.; Rolston, Nicholas; Prasanna, Rohit; Sofia, Sarah; Harwood, Duncan; Ma, Wen; Moghadam, Farhad; Snaith, Henry J.; Buonassisi, Tonio; Holman, Zachary C.; Bent, Stacey F.; McGehee, Michael D.
2017-02-01
As the record single-junction efficiencies of perovskite solar cells now rival those of copper indium gallium selenide, cadmium telluride and multicrystalline silicon, they are becoming increasingly attractive for use in tandem solar cells due to their wide, tunable bandgap and solution processability. Previously, perovskite/silicon tandems were limited by significant parasitic absorption and poor environmental stability. Here, we improve the efficiency of monolithic, two-terminal, 1-cm2 perovskite/silicon tandems to 23.6% by combining an infrared-tuned silicon heterojunction bottom cell with the recently developed caesium formamidinium lead halide perovskite. This more-stable perovskite tolerates deposition of a tin oxide buffer layer via atomic layer deposition that prevents shunts, has negligible parasitic absorption, and allows for the sputter deposition of a transparent top electrode. Furthermore, the window layer doubles as a diffusion barrier, increasing the thermal and environmental stability to enable perovskite devices that withstand a 1,000-hour damp heat test at 85 ∘C and 85% relative humidity.
Simplified Perovskite Solar Cell with 4.1% Efficiency Employing Inorganic CsPbBr3 as Light Absorber.
Duan, Jialong; Zhao, Yuanyuan; He, Benlin; Tang, Qunwei
2018-05-01
Perovskite solar cells with cost-effectiveness, high power conversion efficiency, and improved stability are promising solutions to the energy crisis and environmental pollution. However, a wide-bandgap inorganic-semiconductor electron-transporting layer such as TiO 2 can harvest ultraviolet light to photodegrade perovskite halides, and the high cost of a state-of-the-art hole-transporting layer is an economic burden for commercialization. Here, the building of a simplified cesium lead bromide (CsPbBr 3 ) perovskite solar cell with fluorine-doped tin oxide (FTO)/CsPbBr 3 /carbon architecture by a multistep solution-processed deposition technology is demonstrated, achieving an efficiency as high as 4.1% and improved stability upon interfacial modification by graphene quantum dots and CsPbBrI 2 quantum dots. This work provides new opportunities of building next-generation solar cells with significantly simplified processes and reduced production costs. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Assessing the toxicity of Pb- and Sn-based perovskite solar cells in model organism Danio rerio
Babayigit, Aslihan; Duy Thanh, Dinh; Ethirajan, Anitha; Manca, Jean; Muller, Marc; Boyen, Hans-Gerd; Conings, Bert
2016-01-01
Intensive development of organometal halide perovskite solar cells has lead to a dramatic surge in power conversion efficiency up to 20%. Unfortunately, the most efficient perovskite solar cells all contain lead (Pb), which is an unsettling flaw that leads to severe environmental concerns and is therefore a stumbling block envisioning their large-scale application. Aiming for the retention of favorable electro-optical properties, tin (Sn) has been considered the most likely substitute. Preliminary studies have however shown that Sn-based perovskites are highly unstable and, moreover, Sn is also enlisted as a harmful chemical, with similar concerns regarding environment and health. To bring more clarity into the appropriateness of both metals in perovskite solar cells, we provide a case study with systematic comparison regarding the environmental impact of Pb- and Sn-based perovskites, using zebrafish (Danio Rerio) as model organism. Uncovering an unexpected route of intoxication in the form of acidification, it is shown that Sn based perovskite may not be the ideal Pb surrogate. PMID:26759068
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yoon, Seog Joon; Kuno, Masaru; Kamat, Prashant V.
Minimizing photoinduced segregation in mixed halide lead perovskites is important for achieving stable photovoltaic performance. The shift in the absorption and the rate of formation of iodide- and bromide-rich regions following visible excitation of mixed halide lead perovskites is found to strongly depend on the halide ion concentration. Slower formation and recovery rates observed in halide-deficient films indicate the involvement of defect sites in influencing halide phase segregation. At higher halide concentrations (in stoichiometric excess), segregation effects become less prominent, as evidenced by faster recovery kinetics. These results suggest that light-induced compositional segregation can be minimized in mixed halide perovskitemore » films by using excess halide ions. In conclusion, the findings from this study further reflect the importance of halide ion post-treatment of perovskite films to improve their solar cell performance.« less
Methods for producing single crystal mixed halide perovskites
Zhu, Kai; Zhao, Yixin
2017-07-11
An aspect of the present invention is a method that includes contacting a metal halide and a first alkylammonium halide in a solvent to form a solution and maintaining the solution at a first temperature, resulting in the formation of at least one alkylammonium halide perovskite crystal, where the metal halide includes a first halogen and a metal, the first alkylammonium halide includes the first halogen, the at least one alkylammonium halide perovskite crystal includes the metal and the first halogen, and the first temperature is above about 21.degree. C.
Gorin, Everett
1979-01-01
In a process for hydrocracking heavy polynuclear carbonaceous feedstocks to produce lighter hydrocarbon fuels by contacting the heavy feedstocks with hydrogen in the presence of a molten metal halide catalyst in a hydrocracking zone, thereafter separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide and thereafter regenerating the spent molten metal halide by incinerating the spent molten metal halide by combustion of carbon and sulfur compounds in the spent molten metal halide in an incineration zone, the improvement comprising: (a) contacting the heavy feedstocks and hydrogen in the presence of the molten metal halide in the hydrocracking zone at reaction conditions effective to convert from about 60 to about 90 weight percent of the feedstock to lighter hydrocarbon fuels; (b) separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide; (c) contacting the spent molten metal halide with oxygen in a liquid phase gasification zone at a temperature and pressure sufficient to vaporize from about 25 to about 75 weight percent of the spent metal halide, the oxygen being introduced in an amount sufficient to remove from about 60 to about 90 weight percent of the carbon contained in the spent molten metal halide to produce a fuel gas and regenerated metal halide; and (d) incinerating the spent molten metal halide by combusting carbon and sulfur compounds contained therein.
Systematic analysis of the unique band gap modulation of mixed halide perovskites.
Kim, Jongseob; Lee, Sung-Hoon; Chung, Choong-Heui; Hong, Ki-Ha
2016-02-14
Solar cells based on organic-inorganic hybrid metal halide perovskites have been proven to be one of the most promising candidates for the next generation thin film photovoltaic cells. Mixing Br or Cl into I-based perovskites has been frequently tried to enhance the cell efficiency and stability. One of the advantages of mixed halides is the modulation of band gap by controlling the composition of the incorporated halides. However, the reported band gap transition behavior has not been resolved yet. Here a theoretical model is presented to understand the electronic structure variation of metal mixed-halide perovskites through hybrid density functional theory. Comparative calculations in this work suggest that the band gap correction including spin-orbit interaction is essential to describe the band gap changes of mixed halides. In our model, both the lattice variation and the orbital interactions between metal and halides play key roles to determine band gap changes and band alignments of mixed halides. It is also presented that the band gap of mixed halide thin films can be significantly affected by the distribution of halide composition.
NASA Technical Reports Server (NTRS)
Schlosser, Herbert
1992-01-01
In this note we present two expressions relating the cohesive energy, E(sub coh), and the zero pressure isothermal bulk modulus, B(sub 0), of the alkali halides. Ag halides and TI halides, with the nearest neighbor distances, d(sub nn). First, we show that the product E(sub coh)d(sub 0) within families of halide crystals with common crystal structure is to a good approximation constant, with maximum rms deviation of plus or minus 2%. Secondly, we demonstrate that within families of halide crystals with a common cation and common crystal structure the product B(sub 0)d(sup 3.5)(sub nn) is a good approximation constant, with maximum rms deviation of plus or minus 1.36%.
TRANSURANIC METAL HALIDES AND A PROCESS FOR THE PRODUCTION THEREOF
Fried, S.
1951-03-20
Halides of transuranic elements are prepared by contacting with aluminum and a halogen, or with an aluminum halide, a transuranic metal oxide, oxyhalide, halide, or mixture thereof at an elevated temperature.
APPARATUS FOR THE PRODUCTION OF LITHIUM METAL
Baker, P.S.; Duncan, F.R.; Greene, H.B.
1961-08-22
Methods and apparatus for the production of high-purity lithium from lithium halides are described. The apparatus is provided for continuously contacting a molten lithium halide with molten barium, thereby forming lithium metal and a barium halide, establishing separate layers of these reaction products and unreacted barium and lithium halide, and continuously withdrawing lithium and barium halide from the reaction zone. (AEC)
Process and composition for drying of gaseous hydrogen halides
Tom, Glenn M.; Brown, Duncan W.
1989-08-01
A process for drying a gaseous hydrogen halide of the formula HX, wherein X is selected from the group consisting of bromine, chlorine, fluorine, and iodine, to remove water impurity therefrom, comprising: contacting the water impurity-containing gaseous hydrogen halide with a scavenger including a support having associated therewith one or more members of the group consisting of: (a) an active scavenging moiety selected from one or more members of the group consisting of: (i) metal halide compounds dispersed in the support, of the formula MX.sub.y ; and (ii) metal halide pendant functional groups of the formula -MX.sub.y-1 covalently bonded to the support, wherein M is a y-valent metal, and y is an integer whose value is from 1 to 3; (b) corresponding partially or fully alkylated compounds and/or pendant functional groups, of the metal halide compounds and/or pendant functional groups of (a); wherein the alkylated compounds and/or pendant functional groups, when present, are reactive with the gaseous hydrogen halide to form the corresponding halide compounds and/or pendant functional groups of (a); and M being selected such that the heat of formation, .DELTA.H.sub.f of its hydrated halide, MX.sub.y.(H.sub.2 O).sub.n, is governed by the relationship: .DELTA.H.sub.f .gtoreq.n.times.10.1 kilocalories/mole of such hydrated halide compound wherein n is the number of water molecules bound to the metal halide in the metal halide hydrate. Also disclosed is an appertaining scavenger composition and a contacting apparatus wherein the scavenger is deployed in a bed for contacting with the water impurity-containing gaseous hydrogen halide.
PROCESSING OF URANIUM-METAL-CONTAINING FUEL ELEMENTS
Moore, R.H.
1962-10-01
A process is given for recovering uranium from neutronbombarded uranium- aluminum alloys. The alloy is dissolved in an aluminum halide--alkali metal halide mixture in which the halide is a mixture of chloride and bromide, the aluminum halide is present in about stoichiometric quantity as to uranium and fission products and the alkali metal halide in a predominant quantity; the uranium- and electropositive fission-products-containing salt phase is separated from the electronegative-containing metal phase; more aluminum halide is added to the salt phase to obtain equimolarity as to the alkali metal halide; adding an excess of aluminum metal whereby uranium metal is formed and alloyed with the excess aluminum; and separating the uranium-aluminum alloy from the fission- productscontaining salt phase. (AEC)
Zgliczyński, J M; Stelmaszyńska, T; Olszowska, E; Krawczyk, A; Kwasnowska, E; Wróbel, J T
1983-01-01
It was found that all halides can compete with cyanide for binding with myeloperoxidase. The lower is the pH, the higher is the affinity of halides. The apparent dissociation constants (Kd) of myeloperoxidase-cyanide complex were determined in the presence of F-, Cl-, Br- and I- in the pH range of 4 to 7. In slightly acidic pH (4 - 6) fluoride and chloride exhibit a higher affinity towards the enzyme than bromide and iodide. Taking into account competition between cyanide and halides for binding with myeloperoxidase the dissociation constants of halide-myeloperoxidase complexes were calculated. All halides except fluoride can be oxidized by H2O2 in the presence of myeloperoxidase. However, since fluoride can bind with myeloperoxidase, it can competitively inhibit the oxidation of other halides. Fluoride was a competitive inhibitor with respect to other halides as well as to H2O2. Inhibition constants (Ki) for fluoride as a competitive inhibitor with respect to H2O2 increased from iodide oxidation through bromide to chloride oxidation.
RARE-EARTH METAL FISSION PRODUCTS FROM LIQUID U-Bi
Wiswall, R.H.
1960-05-10
Fission product metals can be removed from solution in liquid bismuth without removal of an appreciable quantity of uranium by contacting the liquid metal solution with fused halides, as for example, the halides of sodium, potassium, and lithium and by adding to the contacted phases a quantity of a halide which is unstable relative to the halides of the fission products, a specific unstable halide being MgCl/sub 3/.
Regeneration of zinc halide catalyst used in the hydrocracking of polynuclear hydrocarbons
Gorin, Everett
1978-01-01
Improved recovery of spent molten zinc halide hydro-cracking catalyst is achieved in the oxidative vapor phase regeneration thereof by selective treatment of the zinc oxide carried over by the effluent vapors from the regeneration zone with hydrogen halide gas under conditions favoring the reaction of the zinc oxide with the hydrogen halide, whereby regenerated zinc halide is recovered in a solids-free state with little loss of zinc values.
Morphology-Controlled Synthesis of Organometal Halide Perovskite Inverse Opals.
Chen, Kun; Tüysüz, Harun
2015-11-09
The booming development of organometal halide perovskites in recent years has prompted the exploration of morphology-control strategies to improve their performance in photovoltaic, photonic, and optoelectronic applications. However, the preparation of organometal halide perovskites with high hierarchical architecture is still highly challenging and a general morphology-control method for various organometal halide perovskites has not been achieved. A mild and scalable method to prepare organometal halide perovskites in inverse opal morphology is presented that uses a polystyrene-based artificial opal as hard template. Our method is flexible and compatible with different halides and organic ammonium compositions. Thus, the perovskite inverse opal maintains the advantage of straightforward structure and band gap engineering. Furthermore, optoelectronic investigations reveal that morphology exerted influence on the conducting nature of organometal halide perovskites. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Cation-Dependent Light-Induced Halide Demixing in Hybrid Organic–Inorganic Perovskites
Sutter-Fella, Carolin M.; Ngo, Quynh P.; Cefarin, Nicola; ...
2018-04-30
Mixed cation metal halide perovskites with increased power conversion efficiency, negligible hysteresis, and improved long-term stability under illumination, moisture, and thermal stressing have emerged as promising compounds for photovoltaic and optoelectronic applications. In this paper, we shed light on photoinduced halide demixing using in situ photoluminescence spectroscopy and in situ synchrotron X-ray diffraction (XRD) to directly compare the evolution of composition and phase changes in CH(NH 2) 2CsPb-halide (FACsPb-) and CH 3NH 3Pb-halide (MAPb-) perovskites upon illumination, thereby providing insights into why FACs-perovskites are less prone to halide demixing than MA-perovskites. We find that halide demixing occurs in both materials.more » However, the I-rich domains formed during demixing accumulate strain in FACsPb-perovskites but readily relax in MA-perovskites. The accumulated strain energy is expected to act as a stabilizing force against halide demixing and may explain the higher Br composition threshold for demixing to occur in FACsPb-halides. In addition, we find that while halide demixing leads to a quenching of the high-energy photoluminescence emission from MA-perovskites, the emission is enhanced from FACs-perovskites. This behavior points to a reduction of nonradiative recombination centers in FACs-perovskites arising from the demixing process and buildup of strain. FACsPb-halide perovskites exhibit excellent intrinsic material properties with photoluminescence quantum yields that are comparable to MA-perovskites. Finally, because improved stability is achieved without sacrificing electronic properties, these compositions are better candidates for photovoltaic applications, especially as wide bandgap absorbers in tandem cells.« less
Cation-Dependent Light-Induced Halide Demixing in Hybrid Organic-Inorganic Perovskites.
Sutter-Fella, Carolin M; Ngo, Quynh P; Cefarin, Nicola; Gardner, Kira L; Tamura, Nobumichi; Stan, Camelia V; Drisdell, Walter S; Javey, Ali; Toma, Francesca M; Sharp, Ian D
2018-06-13
Mixed cation metal halide perovskites with increased power conversion efficiency, negligible hysteresis, and improved long-term stability under illumination, moisture, and thermal stressing have emerged as promising compounds for photovoltaic and optoelectronic applications. Here, we shed light on photoinduced halide demixing using in situ photoluminescence spectroscopy and in situ synchrotron X-ray diffraction (XRD) to directly compare the evolution of composition and phase changes in CH(NH 2 ) 2 CsPb-halide (FACsPb-) and CH 3 NH 3 Pb-halide (MAPb-) perovskites upon illumination, thereby providing insights into why FACs-perovskites are less prone to halide demixing than MA-perovskites. We find that halide demixing occurs in both materials. However, the I-rich domains formed during demixing accumulate strain in FACsPb-perovskites but readily relax in MA-perovskites. The accumulated strain energy is expected to act as a stabilizing force against halide demixing and may explain the higher Br composition threshold for demixing to occur in FACsPb-halides. In addition, we find that while halide demixing leads to a quenching of the high-energy photoluminescence emission from MA-perovskites, the emission is enhanced from FACs-perovskites. This behavior points to a reduction of nonradiative recombination centers in FACs-perovskites arising from the demixing process and buildup of strain. FACsPb-halide perovskites exhibit excellent intrinsic material properties with photoluminescence quantum yields that are comparable to MA-perovskites. Because improved stability is achieved without sacrificing electronic properties, these compositions are better candidates for photovoltaic applications, especially as wide bandgap absorbers in tandem cells.
Cation-Dependent Light-Induced Halide Demixing in Hybrid Organic–Inorganic Perovskites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sutter-Fella, Carolin M.; Ngo, Quynh P.; Cefarin, Nicola
Mixed cation metal halide perovskites with increased power conversion efficiency, negligible hysteresis, and improved long-term stability under illumination, moisture, and thermal stressing have emerged as promising compounds for photovoltaic and optoelectronic applications. In this paper, we shed light on photoinduced halide demixing using in situ photoluminescence spectroscopy and in situ synchrotron X-ray diffraction (XRD) to directly compare the evolution of composition and phase changes in CH(NH 2) 2CsPb-halide (FACsPb-) and CH 3NH 3Pb-halide (MAPb-) perovskites upon illumination, thereby providing insights into why FACs-perovskites are less prone to halide demixing than MA-perovskites. We find that halide demixing occurs in both materials.more » However, the I-rich domains formed during demixing accumulate strain in FACsPb-perovskites but readily relax in MA-perovskites. The accumulated strain energy is expected to act as a stabilizing force against halide demixing and may explain the higher Br composition threshold for demixing to occur in FACsPb-halides. In addition, we find that while halide demixing leads to a quenching of the high-energy photoluminescence emission from MA-perovskites, the emission is enhanced from FACs-perovskites. This behavior points to a reduction of nonradiative recombination centers in FACs-perovskites arising from the demixing process and buildup of strain. FACsPb-halide perovskites exhibit excellent intrinsic material properties with photoluminescence quantum yields that are comparable to MA-perovskites. Finally, because improved stability is achieved without sacrificing electronic properties, these compositions are better candidates for photovoltaic applications, especially as wide bandgap absorbers in tandem cells.« less
40 CFR 721.530 - Substituted aliphatic acid halide (generic name).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted aliphatic acid halide... Specific Chemical Substances § 721.530 Substituted aliphatic acid halide (generic name). (a) Chemical... acid halide (PMN P-84-491) is subject to reporting under this section for the significant new uses...
40 CFR 721.530 - Substituted aliphatic acid halide (generic name).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted aliphatic acid halide... Specific Chemical Substances § 721.530 Substituted aliphatic acid halide (generic name). (a) Chemical... acid halide (PMN P-84-491) is subject to reporting under this section for the significant new uses...
PREPARATION OF URANIUM-ALUMINUM ALLOYS
Moore, R.H.
1962-09-01
A process is given for preparing uranium--aluminum alloys from a solution of uranium halide in an about equimolar molten alkali metal halide-- aluminum halide mixture and excess aluminum. The uranium halide is reduced and the uranium is alloyed with the excess aluminum. The alloy and salt are separated from each other. (AEC)
Sun, Haoxuan; Deng, Kaimo; Zhu, Yayun; Liao, Min; Xiong, Jie; Li, Yanrong; Li, Liang
2018-05-22
Lead halide perovskite solar cells (PSCs) with the high power conversion efficiency (PCE) typically use mesoporous metal oxide nanoparticles as the scaffold and electron-transport layers. However, the traditional mesoporous layer suffers from low electron conductivity and severe carrier recombination. Here, antimony-doped tin oxide nanorod arrays are proposed as novel transparent conductive mesoporous layers in PSCs. Such a mesoporous layer improves the electron transport as well as light utilization. To resolve the common problem of uneven growth of perovskite on rough surface, the dynamic two-step spin coating strategy is proposed to prepare highly smooth, dense, and crystallized perovskite films with micrometer-scale grains, largely reducing the carrier recombination ratio. The conductive mesoporous layer and high-quality perovskite film eventually render the PSC with a remarkable PCE of 20.1% with excellent reproducibility. These findings provide a new avenue to further design high-efficiency PSCs from the aspect of carrier transport and recombination. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Stroppa, Alessandro; di Sante, Domenico; Barone, Paolo; Bokdam, Menno; Kresse, Georg; Franchini, Cesare; Whangbo, Myung-Hwan; Picozzi, Silvia
2014-12-01
Ferroelectricity is a potentially crucial issue in halide perovskites, breakthrough materials in photovoltaic research. Using density functional theory simulations and symmetry analysis, we show that the lead-free perovskite iodide (FA)SnI3, containing the planar formamidinium cation FA, (NH2CHNH2)+, is ferroelectric. In fact, the perpendicular arrangement of FA planes, leading to a ‘weak’ polarization, is energetically more stable than parallel arrangements of FA planes, being either antiferroelectric or ‘strong’ ferroelectric. Moreover, we show that the ‘weak’ and ‘strong’ ferroelectric states with the polar axis along different crystallographic directions are energetically competing. Therefore, at least at low temperatures, an electric field could stabilize different states with the polarization rotated by π/4, resulting in a highly tunable ferroelectricity appealing for multistate logic. Intriguingly, the relatively strong spin-orbit coupling in noncentrosymmetric (FA)SnI3 gives rise to a co-existence of Rashba and Dresselhaus effects and to a spin texture that can be induced, tuned and switched by an electric field controlling the ferroelectric state.
Metal-metal bonds in f-element chemistry.
Liddle, Stephen T; Mills, David P
2009-08-07
The molecular chemistry of the f-elements is traditionally dominated by the use of carbon-, nitrogen-, oxygen-, or halide-ligands. However, the use of metal-based fragments as ligands is underdeveloped, which contrasts to the fields of d- and p-block metal-metal complexes that have developed extensively over the last fifty years. This perspective outlines the development of compounds, which possess polarised covalent or donor-acceptor f-element-metal bonds. For this review, the f-element is defined as (i) a group 3 or lanthanide metal: scandium, yttrium, lanthanum to lutetium, or (ii) an actinide metal: thorium, or uranium, and the metal is defined as a d-block transition metal, or a group 13 (aluminium or gallium), a group 14 (silicon, germanium, or tin), or a group 15 (antimony, or bismuth) metal. Silicon, germanium, and antimony are traditionally classified as metalloids but they are included for completeness. This review focuses mainly on complexes that have been structurally authenticated by single-crystal X-ray diffraction studies and we highlight novel aspects of their syntheses, properties, and reactivities.
Zhao, Dewei; Yu, Yue; Wang, Changlei; ...
2017-03-01
Tandem solar cells using only metal-halide perovskite sub-cells are an attractive choice for next-generation solar cells. However, the progress in developing efficient all-perovskite tandem solar cells has been hindered by the lack of high-performance low-bandgap perovskite solar cells. Here in this paper, we report efficient mixed tin-lead iodide low-bandgap (~1.25 eV) perovskite solar cells with open-circuit voltages up to 0.85 V and over 70% external quantum efficiencies in the infrared wavelength range of 700-900 nm, delivering a short-circuit current density of over 29 mA cm -2 and demonstrating suitability for bottom-cell applications in all-perovskite tandem solar cells. Our low-bandgap perovskitemore » solar cells achieve a maximum power conversion efficiency of 17.6% and a certified efficiency of 17.01% with a negligible current-voltage hysteresis. Finally, when mechanically stacked with a ~1.58 eV bandgap perovskite top cell, our best all-perovskite 4-terminal tandem solar cell shows a steady-state efficiency of 21.0%.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Dewei; Yu, Yue; Wang, Changlei
Tandem solar cells using only metal-halide perovskite sub-cells are an attractive choice for next-generation solar cells. However, the progress in developing efficient all-perovskite tandem solar cells has been hindered by the lack of high-performance low-bandgap perovskite solar cells. Here in this paper, we report efficient mixed tin-lead iodide low-bandgap (~1.25 eV) perovskite solar cells with open-circuit voltages up to 0.85 V and over 70% external quantum efficiencies in the infrared wavelength range of 700-900 nm, delivering a short-circuit current density of over 29 mA cm -2 and demonstrating suitability for bottom-cell applications in all-perovskite tandem solar cells. Our low-bandgap perovskitemore » solar cells achieve a maximum power conversion efficiency of 17.6% and a certified efficiency of 17.01% with a negligible current-voltage hysteresis. Finally, when mechanically stacked with a ~1.58 eV bandgap perovskite top cell, our best all-perovskite 4-terminal tandem solar cell shows a steady-state efficiency of 21.0%.« less
Electrolytic systems and methods for making metal halides and refining metals
Holland, Justin M.; Cecala, David M.
2015-05-26
Disclosed are electrochemical cells and methods for producing a halide of a non-alkali metal and for electrorefining the halide. The systems typically involve an electrochemical cell having a cathode structure configured for dissolving a hydrogen halide that forms the halide into a molten salt of the halogen and an alkali metal. Typically a direct current voltage is applied across the cathode and an anode that is fabricated with the non-alkali metal such that the halide of the non-alkali metal is formed adjacent the anode. Electrorefining cells and methods involve applying a direct current voltage across the anode where the halide of the non-alkali metal is formed and the cathode where the non-alkali metal is electro-deposited. In a representative embodiment the halogen is chlorine, the alkali metal is lithium and the non-alkali metal is uranium.
Cu-catalyzed Suzuki-Miyaura reactions of primary and secondary benzyl halides with arylboronates.
Sun, Yan-Yan; Yi, Jun; Lu, Xi; Zhang, Zhen-Qi; Xiao, Bin; Fu, Yao
2014-09-28
A copper-catalyzed Suzuki-Miyaura coupling of benzyl halides with arylboronates is described. Varieties of primary benzyl halides as well as more challenging secondary benzyl halides with β hydrogens or steric hindrance could be successfully converted into the corresponding products. Thus it provides access to diarylmethanes, diarylethanes and triarylmethanes.
Preparation of cerium halide solvate complexes
Vasudevan, Kalyan V; Smith, Nickolaus A; Gordon, John C; McKigney, Edward A; Muenchaussen, Ross E
2013-08-06
Crystals of a solvated cerium(III) halide solvate complex resulted from a process of forming a paste of a cerium(III) halide in an ionic liquid, adding a solvent to the paste, removing any undissolved solid, and then cooling the liquid phase. Diffusing a solvent vapor into the liquid phase also resulted in crystals of a solvated cerium(III) halide complex.
METHOD OF MAKING ALLOYS OF BERYLLIUM WITH PLUTONIUM AND THE LIKE
Runnals, O.J.C.
1959-02-24
The production of alloys of beryllium with one or more of the metals uranium, plutonium, actinium, americium, curium, thorium, and cerium are described. A halide salt of the metal to be alloyed with the beryllium is heated at 1300 deg C in the presence of beryllium to reduce the halide to metal and cause the latter to alloy directly with the beryllium. Although the heavy metal halides are more stable, thermodynamically, than the beryllium halides, the reducing reaction proceeds to completion if the beryllium halide product is continuously removed by vacuum distillation.
Shallow halogen vacancies in halide optoelectronic materials
NASA Astrophysics Data System (ADS)
Shi, Hongliang; Du, Mao-Hua
2014-11-01
Halogen vacancies (VH ) are usually deep color centers (F centers) in halides and can act as major electron traps or recombination centers. The deep VH contributes to the typically poor carrier transport properties in halides. However, several halides have recently emerged as excellent optoelectronic materials, e.g., C H3N H3Pb I3 and TlBr. Both C H3N H3Pb I3 and TlBr have been found to have shallow VH , in contrast to commonly seen deep VH in halides. In this paper, several halide optoelectronic materials, i.e., C H3N H3Pb I3 , C H3N H3Sn I3 (photovoltaic materials), TlBr, and CsPbB r3 (gamma-ray detection materials) are studied to understand the material chemistry and structure that determine whether VH is a shallow or deep defect in a halide material. It is found that crystal structure and chemistry of n s2 ions both play important roles in creating shallow VH in halides such as C H3N H3Pb I3 , C H3N H3Sn I3 , and TlBr. The key to identifying halides with shallow VH is to find the right crystal structures and compounds that suppress cation orbital hybridization at VH , such as those with large cation-cation distances and low anion coordination numbers and those with crystal symmetry that prevents strong hybridization of cation dangling bond orbitals at VH . The results of this paper provide insight and guidance to identifying halides with shallow VH as good electronic and optoelectronic materials.
A review of bacterial methyl halide degradation: biochemistry, genetics and molecular ecology
McDonald, I.R.; Warner, K.L.; McAnulla, C.; Woodall, C.A.; Oremland, R.S.; Murrell, J.C.
2002-01-01
Methyl halide-degrading bacteria are a diverse group of organisms that are found in both terrestrial and marine environments. They potentially play an important role in mitigating ozone depletion resulting from methyl chloride and methyl bromide emissions. The first step in the pathway(s) of methyl halide degradation involves a methyltransferase and, recently, the presence of this pathway has been studied in a number of bacteria. This paper reviews the biochemistry and genetics of methyl halide utilization in the aerobic bacteria Methylobacterium chloromethanicum CM4T, Hyphomicrobium chloromethanicum CM2T, Aminobacter strain IMB-1 and Aminobacter strain CC495. These bacteria are able to use methyl halides as a sole source of carbon and energy, are all members of the α-Proteobacteria and were isolated from a variety of polluted and pristine terrestrial environments. An understanding of the genetics of these bacteria identified a unique gene (cmuA) involved in the degradation of methyl halides, which codes for a protein (CmuA) with unique methyltransferase and corrinoid functions. This unique functional gene, cmuA, is being used to develop molecular ecology techniques to examine the diversity and distribution of methyl halide-utilizing bacteria in the environment and hopefully to understand their role in methyl halide degradation in different environments. These techniques will also enable the detection of potentially novel methyl halide-degrading bacteria.
10 CFR Appendix B to Subpart S to... - Certification Report for Metal Halide Lamp Ballasts
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 3 2011-01-01 2011-01-01 false Certification Report for Metal Halide Lamp Ballasts B... PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Metal Halide Lamp Ballasts and Fixtures Pt. 431, Subpt. S, App. B Appendix B to Subpart S to Part 431—Certification Report for Metal Halide Lamp Ballasts...
Method for recovering hydrocarbons from molten metal halides
Pell, Melvyn B.
1979-01-01
In a process for hydrocracking heavy carbonaceous materials by contacting such carbonaceous materials with hydrogen in the presence of a molten metal halide catalyst to produce hydrocarbons having lower molecular weights and thereafter recovering the hydrocarbons so produced from the molten metal halide, an improvement comprising injecting into the spent molten metal halide, a liquid low-boiling hydrocarbon stream is disclosed.
Investigation of surface halide modification of nitrile butadiene rubber
NASA Astrophysics Data System (ADS)
Sukhareva, K. V.; Mikhailov, I. A.; Andriasyan, Yu O.; Mastalygina, E. E.; Popov, A. A.
2017-12-01
The investigation is devoted to the novel technology of surface halide modification of rubber samples based on nitrile butadiene rubber (NBR). 1,1,2-trifluoro-1,2,2-trichlorethane was used as halide modifier. The developed technology is characterized by production stages reduction to one by means of treating the rubber compound with a halide modifier. The surface halide modification of compounds based on nitrile butadiene rubber (NBR) was determined to result in increase of resistance to thermal oxidation and aggressive media. The conducted research revealed the influence of modification time on chemical resistance and physical-mechanical properties of rubbers under investigation.
Method of making alloys of beryllium with plutonium and the like
Runnals, O J.C.
1959-02-24
The production or alloys of beryllium with one or more of the metals uranium, plutonium, actinium, americium, curium, thorium, and cerium is described. A halide salt or the metal to be alloyed with the beryllium is heated at l3O0 deg C in the presence of beryllium to reduce the halide to metal and cause the latter to alloy directly with the beryllium. Although the heavy metal halides are more stable, thermodynamically, than the beryllium halides, the reducing reaction proceeds to completion if the beryllium halide product is continuously removed by vacuum distillation.
Gorin, Everett
1979-01-01
In a process for hydrocracking heavy polynuclear carbonaceous feedstocks to produce lighter hydrocarbon fuels by contacting the heavy feedstocks with hydrogen in the presence of a molten metal halide catalyst, thereafter separating at least a substantial portion of the carbonaceous material associated with the reaction mixture from the spent molten metal halide and thereafter regenerating the metal halide catalyst, an improvement comprising contacting the spent molten metal halide catalyst after removal of a major portion of the carbonaceous material therefrom with an additional quantity of hydrogen is disclosed.
ELECTROLYTIC PROCESS FOR PRODUCING METALS
Kopelman, B.; Holden, R.B.
1961-06-01
A method is described for reducing beryllium halides to beryllium. The beryllfum halide fs placed in an eutectic mixture of alkali halides and alkaline earth halides. The constituents of this eutectic bath are so chosen that it has a melting point less than the boiling point of mercury, which acts as a cathode for the system. The beryllium metal is then deposited in the mercury upon electrolysis.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 12 2011-07-01 2009-07-01 true Emission Limits for Hydrogen Halide and... to Subpart FFFF of Part 63—Emission Limits for Hydrogen Halide and Halogen HAP Emissions or HAP... following table that applies to your process vents that contain hydrogen halide and halogen HAP emissions or...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Emission Limits for Hydrogen Halide and... to Subpart FFFF of Part 63—Emission Limits for Hydrogen Halide and Halogen HAP Emissions or HAP... following table that applies to your process vents that contain hydrogen halide and halogen HAP emissions or...
Code of Federal Regulations, 2011 CFR
2011-07-01
... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... Compliance Requirements § 63.2465 What requirements must I meet for process vents that emit hydrogen halide... section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you must...
Unraveling luminescence mechanisms in zero-dimensional halide perovskites
Han, Dan; Shi, Hongliang; Ming, Wenmei; ...
2018-01-01
Zero-dimensional (0D) halides perovskites, in which anionic metal-halide octahedra (MX 6 ) 4− are separated by organic or inorganic countercations, have recently shown promise as excellent luminescent materials.
Unraveling luminescence mechanisms in zero-dimensional halide perovskites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, Dan; Shi, Hongliang; Ming, Wenmei
Zero-dimensional (0D) halides perovskites, in which anionic metal-halide octahedra (MX 6 ) 4− are separated by organic or inorganic countercations, have recently shown promise as excellent luminescent materials.
Shallow halogen vacancies in halide optoelectronic materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, Hongliang; Du, Mao -Hua
2014-11-05
Halogen vacancies (V H) are usually deep color centers (F centers) in halides and can act as major electron traps or recombination centers. The deep V H contributes to the typically poor carrier transport properties in halides. However, several halides have recently emerged as excellent optoelectronic materials, e.g., CH 3NH 3PbI 3 and TlBr. Both CH 3NH 3PbI 3 and TlBr have been found to have shallow V H, in contrast to commonly seen deep V H in halides. In this paper, several halide optoelectronic materials, i.e., CH 3NH 3PbI 3, CH 3NH 3SnI 3 (photovoltaic materials), TlBr, and CsPbBrmore » 3, (gamma-ray detection materials) are studied to understand the material chemistry and structure that determine whether V H is a shallow or deep defect in a halide material. It is found that crystal structure and chemistry of ns 2 ions both play important roles in creating shallow V H in halides such as CH 3NH 3PbI 3, CH 3NH 3SnI 3, and TlBr. The key to identifying halides with shallow V H is to find the right crystal structures and compounds that suppress cation orbital hybridization at V H, such as those with long cation-cation distances and low anion coordination numbers, and those with crystal symmetry that prevents strong hybridization of cation dangling bond orbitals at V H. Furthermore, the results of this paper provide insight and guidance to identifying halides with shallow V H as good electronic and optoelectronic materials.« less
Unraveling luminescence mechanisms in zero-dimensional halide perovskites
Han, Dan; Shi, Hongliang; Ming, Wenmei; ...
2018-05-18
Here, zero-dimensional (0D) halides perovskites, in which anionic metal-halide octahedra (MX 6) 4– are separated by organic or inorganic countercations, have recently shown promise as excellent luminescent materials.
Luminescent zero-dimensional organic metal halide hybrids with near-unity quantum efficiency.
Zhou, Chenkun; Lin, Haoran; Tian, Yu; Yuan, Zhao; Clark, Ronald; Chen, Banghao; van de Burgt, Lambertus J; Wang, Jamie C; Zhou, Yan; Hanson, Kenneth; Meisner, Quinton J; Neu, Jennifer; Besara, Tiglet; Siegrist, Theo; Lambers, Eric; Djurovich, Peter; Ma, Biwu
2018-01-21
Single crystalline zero-dimensional (0D) organic-inorganic hybrid materials with perfect host-guest structures have been developed as a new generation of highly efficient light emitters. Here we report a series of lead-free organic metal halide hybrids with a 0D structure, (C 4 N 2 H 14 X) 4 SnX 6 (X = Br, I) and (C 9 NH 20 ) 2 SbX 5 (X = Cl), in which the individual metal halide octahedra (SnX 6 4- ) and quadrangular pyramids (SbX 5 2- ) are completely isolated from each other and surrounded by the organic ligands C 4 N 2 H 14 X + and C 9 NH 20 + , respectively. The isolation of the photoactive metal halide species by the wide band gap organic ligands leads to no interaction or electronic band formation between the metal halide species, allowing the bulk materials to exhibit the intrinsic properties of the individual metal halide species. These 0D organic metal halide hybrids can also be considered as perfect host-guest systems, with the metal halide species periodically doped in the wide band gap matrix. Highly luminescent, strongly Stokes shifted broadband emissions with photoluminescence quantum efficiencies (PLQEs) of close to unity were realized, as a result of excited state structural reorganization of the individual metal halide species. Our discovery of highly luminescent single crystalline 0D organic-inorganic hybrid materials as perfect host-guest systems opens up a new paradigm in functional materials design.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 13 2013-07-01 2012-07-01 true Emission Limits for Hydrogen Halide and..., Table 3 Table 3 to Subpart FFFF of Part 63—Emission Limits for Hydrogen Halide and Halogen HAP Emissions... limit in the following table that applies to your process vents that contain hydrogen halide and halogen...
Code of Federal Regulations, 2014 CFR
2014-07-01
... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... hydrogen halide and halogen HAP or HAP metals? (a) You must meet each emission limit in Table 3 to this...) of this section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you...
Code of Federal Regulations, 2013 CFR
2013-07-01
... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... hydrogen halide and halogen HAP or HAP metals? (a) You must meet each emission limit in Table 3 to this...) of this section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 13 2014-07-01 2014-07-01 false Emission Limits for Hydrogen Halide.... FFFF, Table 3 Table 3 to Subpart FFFF of Part 63—Emission Limits for Hydrogen Halide and Halogen HAP... limit in the following table that applies to your process vents that contain hydrogen halide and halogen...
Code of Federal Regulations, 2012 CFR
2012-07-01
... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... hydrogen halide and halogen HAP or HAP metals? (a) You must meet each emission limit in Table 3 to this...) of this section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 13 2012-07-01 2012-07-01 false Emission Limits for Hydrogen Halide.... FFFF, Table 3 Table 3 to Subpart FFFF of Part 63—Emission Limits for Hydrogen Halide and Halogen HAP... limit in the following table that applies to your process vents that contain hydrogen halide and halogen...
Deuterium separation by infrared-induced addition reaction
Marling, John B.
1977-01-01
A method for deuterium enrichment by the infrared-induced addition reaction of a deuterium halide with an unsaturated aliphatic compound. A gaseous mixture of a hydrogen halide feedstock and an unsaturated aliphatic compound, particularly an olefin, is irradiated to selectively vibrationally excite the deuterium halide contained therein. The excited deuterium halide preferentially reacts with the unsaturated aliphatic compound to produce a deuterated addition product which is removed from the reaction mixture.
Self-Organized Superlattice and Phase Coexistence inside Thin Film Organometal Halide Perovskite.
Kim, Tae Woong; Uchida, Satoshi; Matsushita, Tomonori; Cojocaru, Ludmila; Jono, Ryota; Kimura, Kohei; Matsubara, Daiki; Shirai, Manabu; Ito, Katsuji; Matsumoto, Hiroaki; Kondo, Takashi; Segawa, Hiroshi
2018-02-01
Organometal halide perovskites have attracted widespread attention as the most favorable prospective material for photovoltaic technology because of their high photoinduced charge separation and carrier transport performance. However, the microstructural aspects within the organometal halide perovskite are still unknown, even though it belongs to a crystal system. Here direct observation of the microstructure of the thin film organometal halide perovskite using transmission electron microscopy is reported. Unlike previous reports claiming each phase of the organometal halide perovskite solely exists at a given temperature range, it is identified that the tetragonal and cubic phases coexist at room temperature, and it is confirmed that superlattices composed of a mixture of tetragonal and cubic phases are self-organized without a compositional change. The organometal halide perovskite self-adjusts the configuration of phases and automatically organizes a buffer layer at boundaries by introducing a superlattice. This report shows the fundamental crystallographic information for the organometal halide perovskite and demonstrates new possibilities as promising materials for various applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Effect of halide ions on the photodegradation of ibuprofen in aqueous environments.
Li, Fuhua; Kong, Qingqing; Chen, Ping; Chen, Min; Liu, Guoguang; Lv, Wenying; Yao, Kun
2017-01-01
Typically contained within ambient surface waters and certain industrial wastewaters, are plentiful halide ions, which possess varying degrees of photosensitivity. The effects of halide ions on the photodegradation of ibuprofen (IBP) were investigated under UV irradiation using a 500 W mercury lamp as a light source. Studies of the mechanism of halide ions were inclusive of both their light shielding effects and quenching experiments. The results indicated that chloride ion has a slight inhibition against IBP photodegradation under neutral condition, and significant inhibition is observed with bromide ions and iodide ions. In addition to the observed increased rate of IBP photodegradation in conjunction with elevated pH in solution, the inhibitory effect of halide ions was different. When the pH value of the IBP solution was 5, chloride ions were seen to facilitate the photodegradation of IBP. Halide ions can inhibit IBP photodegradation by means of a light attenuation effect. All of the halide ions significantly facilitated the generation of 1 O 2 . Copyright © 2016 Elsevier Ltd. All rights reserved.
10 CFR 431.322 - Definitions concerning metal halide lamp ballasts and fixtures.
Code of Federal Regulations, 2010 CFR
2010-01-01
... is produced by radiation of metal halides and their products of dissociation, possibly in combination... electromagnetic ballast that starts a pulse-start metal halide lamp with high voltage pulses, where lamps shall be...
Effects of Halides on Plasmid-Mediated Silver Resistance in Escherichia coli
Gupta, Amit; Maynes, Maria; Silver, Simon
1998-01-01
Silver resistance of sensitive Escherichia coli J53 and resistance plasmid-containing J53(pMG101) was affected by halides in the growth medium. The effects of halides on Ag+ resistance were measured with AgNO3 and silver sulfadiazine, both on agar and in liquid. Low concentrations of chloride made the differences in MICs between sensitive and resistant strains larger. High concentrations of halides increased the sensitivities of both strains to Ag+. PMID:9835606
Effects of halides on plasmid-mediated silver resistance in Escherichia coli.
Gupta, A; Maynes, M; Silver, S
1998-12-01
Silver resistance of sensitive Escherichia coli J53 and resistance plasmid-containing J53(pMG101) was affected by halides in the growth medium. The effects of halides on Ag+ resistance were measured with AgNO3 and silver sulfadiazine, both on agar and in liquid. Low concentrations of chloride made the differences in MICs between sensitive and resistant strains larger. High concentrations of halides increased the sensitivities of both strains to Ag+.
Doane, Tennyson L.; Ryan, Kayla L.; Pathade, Laxmikant; ...
2016-05-05
The ability of cesium lead halide (CsPbX 3; X = Cl –, Br –, I –) perovskite nanoparticles (P-NPs) to participate in halide exchange reactions, to catalyze Finkelstein organohalide substitution reactions, and to colorimetrically monitor chemical reactions and detect anions in real time is described. With the use of tetraoctylammonium halide salts as a starting point, halide exchange with the P-NPs was performed to calibrate reactivity, stability, and extent of ion exchange. Also, the exchange of CsPbI 3 with Cl – or Br – causes a significant blue-shift in absorption and photoluminescence, whereas reacting I – with CsPbBr 3 causesmore » a red-shift of similar magnitudes. With the high local halide concentrations and the facile nature of halide exchange in mind, we then explored the ability of P-NPs to catalyze organohalide exchange in Finkelstein like reactions. Results indicate that the P-NPs serve as excellent halide reservoirs for substitution of organohalides in nonpolar media, leading to not only different organohalide products, but also a complementary color change over the course of the reaction, which can be used to monitor kinetics in a precise manner. Finally, the merits of using P-NP as spectrochemical probes for real time assaying is then expanded to other anions which can react with, or result in unique, classes of perovskites.« less
Code of Federal Regulations, 2011 CFR
2011-01-01
... Metal Halide Lamp Ballasts and Fixtures Energy Conservation Standards § 431.329 Enforcement. Process for Metal Halide Lamp Ballasts. This section sets forth procedures DOE will follow in pursuing alleged... with the following statistical sampling procedures for metal halide lamp ballasts, with the methods...
Ohmiya, Hirohisa; Tsuji, Takashi; Yorimitsu, Hideki; Oshima, Koichiro
2004-11-05
Details of cobalt-catalyzed cross-coupling reactions of alkyl halides with allylic Grignard reagents are disclosed. A combination of cobalt(II) chloride and 1,2-bis(diphenylphosphino)ethane (DPPE) or 1,3-bis(diphenylphosphino)propane (DPPP) is suitable as a precatalyst and allows secondary and tertiary alkyl halides--as well as primary ones--to be employed as coupling partners for allyl Grignard reagents. The reaction offers a facile synthesis of quaternary carbon centers, which has practically never been possible with palladium, nickel, and copper catalysts. Benzyl, methallyl, and crotyl Grignard reagents can all couple with alkyl halides. The benzylation definitely requires DPPE or DPPP as a ligand. The reaction mechanism should include the generation of an alkyl radical from the parent alkyl halide. The mechanism can be interpreted in terms of a tandem radical cyclization/cross-coupling reaction. In addition, serendipitous tandem radical cyclization/cyclopropanation/carbonyl allylation of 5-alkoxy-6-halo-4-oxa-1-hexene derivatives is also described. The intermediacy of a carbon-centered radical results in the loss of the original stereochemistry of the parent alkyl halides, creating the potential for asymmetric cross-coupling of racemic alkyl halides.
Gorin, Everett
1981-01-01
A method for hydrocracking a heavy polynuclear hydrocarbonaceous feedstock to produce lighter hydrocarbon fuels by contacting the feedstock with hydrogen in the presence of a molten metal halide catalyst, the method comprising: mixing the feedstock with a heavy naphtha fraction which has an initial boiling point from about 100.degree. to about 160.degree. C. with a boiling point difference between the initial boiling point and the final boiling point of no more than about 50.degree. C. to produce a mixture; thereafter contacting the mixture with partially spent molten metal halide and hydrogen under temperature and pressure conditions so that the temperature is near the critical temperature of the heavy naphtha fraction; separating at least a portion of the heavy naphtha fraction and lighter hydrocarbon fuels from the partially spent molten metal halide, unreacted feedstock and reaction products; thereafter contacting the partially spent molten metal halide, unreacted feedstock and reaction products with hydrogen and fresh molten metal halide in a hydrocracking zone to produce additional lighter hydrocarbon fuels and separating at least a major portion of the lighter hydrocarbon fuels from the spent molten metal halide.
NASA Astrophysics Data System (ADS)
Zhang, Lei; Yu, Fengxi; Chen, Lihong; Li, Jingfa
2018-06-01
Organic additives, such as the Lewis base thiophene, have been successfully applied to passivate halide perovskite surfaces, improving the stability and properties of perovskite devices based on CH3NH3PbI3. Yet, the detailed nanostructure of the perovskite surface passivated by additives and the mechanisms of such passivation are not well understood. This study presents a nanoscopic view on the interfacial structure of an additive/perovskite interface, consisting of a Lewis base thiophene molecular additive and a lead halide perovskite surface substrate, providing insights on the mechanisms that molecular additives can passivate the halide perovskite surfaces and enhance the perovskite-based device performance. Molecular dynamics study on the interactions between water molecules and the perovskite surfaces passivated by the investigated additive reveal the effectiveness of employing the molecular additives to improve the stability of the halide perovskite materials. The additive/perovskite surface system is further probed via molecular engineering the perovskite surfaces. This study reveals the nanoscopic structure-property relationships of the halide perovskite surface passivated by molecular additives, which helps the fundamental understanding of the surface/interface engineering strategies for the development of halide perovskite based devices.
Samu, Gergely F.; Janaky, Csaba; Kamat, Prashant V.
2017-07-24
Photoinduced segregation in mixed halide perovskites has a direct influence on decreasing the solar cell efficiency as segregated I-rich domains serve as charge recombination centers. Here, the changes in the external quantum efficiency mirror the spectral loss in the absorption; however, the time scale of the IPCE recovery in the dark is slower than the absorption recovery, showing the intricate nature of the photoinduced halide segregation and charge collection in solar cell devices.
NASA Astrophysics Data System (ADS)
Shibata, Mikihiro; Kandori, Hideki
2007-12-01
Bacteriorhodopsin (BR), a membrane protein found in Halobacterium salinarum, functions as a light-driven proton pump. The Schiff base region has a quadropolar structure with positive charges located at the protonated Schiff base and Arg82, and counterbalancing negative charges located at Asp85 and Asp212 (Figure 1A). It is known that BR lacks a proton-pumping activity if Asp85 or Asp212 is neutralized by mutation. On the other hand, binding of C1- brings different effects for pumping functions in mutants at D85 and D212 position. While C1--bound D85T and D85S pump C1-, photovoltage measurements suggested that C1--bound D212N pumps protons at low pH. In this study, we measured low-temperature FTIR spectra of D85S and D212N containing various halides to compare the halide binding site of both proteins. In the case of D85S, the N-D stretching vibrations of the Schiff base were halide-dependent. This result suggests that the halide is a hydrogen-bond acceptor of the Schiff base, being consistent with the X-ray crystal structure. On the other hand, no halide dependence was observed for vibrational bands of the retinal skeleton and the Schiff base in the D212N mutant. This result suggests that the halide does not form a hydrogen bond with the Schiff base directly, unlike the mutation at D85 position. Halide-dependent water bands in the Schiff base region also differ between D85S and D212N. From these results, halide binding site of both proteins and role of two negative charges in BR will be discussed.
Heat capacity of molten halides.
Redkin, Alexander A; Zaikov, Yurii P; Korzun, Iraida V; Reznitskikh, Olga G; Yaroslavtseva, Tatiana V; Kumkov, Sergey I
2015-01-15
The heat capacities of molten salts are very important for their practical use. Experimental investigation of this property is challenging because of the high temperatures involved and the corrosive nature of these materials. It is preferable to combine experimental investigations with empirical relationships, which allows for the evaluation of the heat capacity of molten salt mixtures. The isobaric molar heat capacities of all molten alkali and alkaline-earth halides were found to be constant for each group of salts. The value depends on the number of atoms in the salt, and the molar heat capacity per atom is constant for all molten halide salts with the exception of the lithium halides. The molar heat capacities of molten halides do not change when the anions are changed.
Investigation of a light fixture fire
Jurney, James D.; Cournoyer, Michael E.; Trujillo, Stanley; ...
2016-04-16
Metal-halide lamps produce light by discharging an electric arc through a gaseous mixture of vaporized mercury and metal halides. Metal-halide lamps for use in spaces with lower mounting heights can produce excessive visual glare in the normal, higher field-of-view unless they are equipped with prismatic lenses. Should the bulb fail, high internal operating pressure of the arc tube can launch fragments of arc tube at high velocity in all directions, striking the outer bulb of the lamp with enough force to cause the outer bulb to break. This article reports an investigation of a light fixture fire and reviews amore » case study of a metal-halide lamp fire. We reported on causal analysis of the metal-halide lamp fire uncovered contributing factors that created the environment in which the incident occurred. Latent organizational conditions that created error-likely situations or weakened defenses were identified and controlled. Lastly, effective improvements that reduce the probability or consequence of similar metal-halide lamp fire incidents were implemented.« less
Investigation of a light fixture fire
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jurney, James D.; Cournoyer, Michael E.; Trujillo, Stanley
Metal-halide lamps produce light by discharging an electric arc through a gaseous mixture of vaporized mercury and metal halides. Metal-halide lamps for use in spaces with lower mounting heights can produce excessive visual glare in the normal, higher field-of-view unless they are equipped with prismatic lenses. Should the bulb fail, high internal operating pressure of the arc tube can launch fragments of arc tube at high velocity in all directions, striking the outer bulb of the lamp with enough force to cause the outer bulb to break. This article reports an investigation of a light fixture fire and reviews amore » case study of a metal-halide lamp fire. We reported on causal analysis of the metal-halide lamp fire uncovered contributing factors that created the environment in which the incident occurred. Latent organizational conditions that created error-likely situations or weakened defenses were identified and controlled. Lastly, effective improvements that reduce the probability or consequence of similar metal-halide lamp fire incidents were implemented.« less
NASA Astrophysics Data System (ADS)
Jiao, Y.; Acdan, J.; Xu, R.; Deventer, M. J.; Rhew, R. C.
2017-12-01
A precise quantification of global methyl halide budgets is needed to evaluate the ozone depletion potential of these compounds and to predict future changes of stratospheric ozone. However, the global budgets of methyl halides are not balanced between currently identified and quantified sources and sinks. Our study re-evaluated the methyl bromide budget from global cultivated rapeseed (Brassica napus) through life-cycle flux measurements both in the greenhouse and in the field, yielding a methyl bromide emission rate that scales globally to 1.0 - 1.2 Gg yr-1. While this indicates a globally significant source, it is much smaller than the previously widely cited value of 5 - 6 Gg yr-1(Mead et al., 2008), even taking into account the near tripling of annual global yield of rapeseed since the previous evaluation was conducted. Our study also evaluated the methyl chloride and methyl iodide emission levels from rapeseed, yielding emission rates that scale to 5.4 Gg yr-1 for methyl chloride and 1.8 Gg yr-1 of methyl iodide. The concentrations of the methyl donor SAM (S-adenosyl methionine) and the resultant product SAH (S-Adenosyl-L-homocysteine) were also analyzed to explore their role in biogenic methyl halide formation. Halide gradient incubations showed that the magnitude of methyl halide emissions from rapeseed is highly correlated to soil halide levels, thus raising the concern that the heterogeneity of soil halide contents geographically should be considered when extrapolating to global budget.
Bu, Tongle; Shi, Shengwei; Li, Jing; Liu, Yifan; Shi, Jielin; Chen, Li; Liu, Xueping; Qiu, Junhao; Ku, Zhiliang; Peng, Yong; Zhong, Jie; Cheng, Yi-Bing; Huang, Fuzhi
2018-05-02
Organic-inorganic metal halide perovskite solar cells (PSCs) have been emerging as one of the most promising next generation photovoltaic technologies with a breakthrough power conversion efficiency (PCE) over 22%. However, aiming for commercialization, it still encounters challenges for the large-scale module fabrication, especially for flexible devices which have attracted intensive attention recently. Low-temperature processed high-performance electron-transporting layers (ETLs) are still difficult. Herein, we present a facile low-temperature synthesis of crystalline SnO 2 nanocrystals (NCs) as efficient ETLs for flexible PSCs including modules. Through thermal and UV-ozone treatments of the SnO 2 ETLs, the electron transporting resistance of the ETLs and the charge recombination at the interface of ETL/perovskite were decreased. Thus, the hysteresis-free highly efficient rigid and flexible PSCs were obtained with PCEs of 19.20 and 16.47%, respectively. Finally, a 5 × 5 cm 2 flexible PSC module with a PCE of 12.31% (12.22% for forward scan and 12.40% for reverse scan) was fabricated with the optimized perovskite/ETL interface. Thus, employing presynthesized SnO 2 NCs to fabricate ETLs has showed promising for future manufacturing.
THE DETERMINATION OF TOTAL ORGANIC HALIDE IN WATER: A COMPARATIVE STUDY OF TWO INSTRUMENTS
Total organic halide (TOX) analyzers are commonly used to measure the amount of dissolved halogenated organic byproducts in disinfected waters. ecause of the lack of information on the identity of disinfection byproducts, rigorous testing of the dissolved organic halide (DOX) pro...
10 CFR Appendix C to Part 20 - Quantities 1 of Licensed Material Requiring Labeling
Code of Federal Regulations, 2012 CFR
2012-01-01
... Indium-115 100 Indium-116m 1,000 Indium-117m 1,000 Indium-117 1,000 Indium-119m 1,000 Tin-110 100 Tin-111 1,000 Tin-113 100 Tin-117m 100 Tin-119m 100 Tin-121m 100 Tin-121 1,000 Tin-123m 1,000 Tin-123 10 Tin-125 10 Tin-126 10 Tin-127 1,000 Tin-128 1,000 Antimony-115 1,000 Antimony-116m 1,000 Antimony-116 1...
10 CFR 431.327 - Submission of data.
Code of Federal Regulations, 2011 CFR
2011-01-01
... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures Energy Conservation Standards § 431.327 Submission of data.... (2) Each manufacturer or private labeler of a basic model of metal halide lamp ballast shall file a... certification report for each of its metal halide lamp ballast basic models. The certification report (for which...
Total organic halide (TOX) analyzers are commonly used to measure the amount of dissolved halogenated organic byproducts in disinfected waters. Because of the lack of information on the identity of disinfection byproducts, rigorous testing of the dissolved organic halide (DOX) pr...
Silver-halide gelatin holograms
NASA Astrophysics Data System (ADS)
Chang, B. J.; Winick, K.
1980-05-01
The use of a silver-halide gelatin for volume phase holograms having a wide spectral response and lower exposure requirements than alternatives and using commercially available silver salts, is proposed. The main difference between the dichromated gelatin and silver-halide processes is the creation of a hologram latent image, which is given in the form of a hardness differential between exposed and unexposed regions in the silver halide hologram; the differential is in turn created by the reaction products of either tanning development or tanning bleach, which harden the gelatin with link-bonds between molecules.
New silver-halide-sensitized gelatin material: the influence of bleaches on holograms
NASA Astrophysics Data System (ADS)
Zhang, Weiping; Pang, Lin; Guo, Lurong
1996-12-01
A new high-resolution-silver-halide (HRSH-II) material was produced, which has proper initial hardness for fabricating silver halide sensitized gelatin (SHSG) holograms. That would avoid high noise by seeking the gelatin in hot water. With different alkali halide component in B solution and its concentration (the ratio B/A), experiments were presented about bleaching effect with R-10 on processing for SHSG derived from this new material. High diffraction efficiency, as high as 81%, was achieved. Some of the observations are discussed.
Lignos, Ioannis; Stavrakis, Stavros; Nedelcu, Georgian; Protesescu, Loredana; deMello, Andrew J; Kovalenko, Maksym V
2016-03-09
Prior to this work, fully inorganic nanocrystals of cesium lead halide perovskite (CsPbX3, X = Br, I, Cl and Cl/Br and Br/I mixed halide systems), exhibiting bright and tunable photoluminescence, have been synthesized using conventional batch (flask-based) reactions. Unfortunately, our understanding of the parameters governing the formation of these nanocrystals is still very limited due to extremely fast reaction kinetics and multiple variables involved in ion-metathesis-based synthesis of such multinary halide systems. Herein, we report the use of a droplet-based microfluidic platform for the synthesis of CsPbX3 nanocrystals. The combination of online photoluminescence and absorption measurements and the fast mixing of reagents within such a platform allows the rigorous and rapid mapping of the reaction parameters, including molar ratios of Cs, Pb, and halide precursors, reaction temperatures, and reaction times. This translates into enormous savings in reagent usage and screening times when compared to analogous batch synthetic approaches. The early-stage insight into the mechanism of nucleation of metal halide nanocrystals suggests similarities with multinary metal chalcogenide systems, albeit with much faster reaction kinetics in the case of halides. Furthermore, we show that microfluidics-optimized synthesis parameters are also directly transferrable to the conventional flask-based reaction.
2018-01-01
We propose here a new colloidal approach for the synthesis of both all-inorganic and hybrid organic–inorganic lead halide perovskite nanocrystals (NCs). The main limitation of the protocols that are currently in use, such as the hot injection and the ligand-assisted reprecipitation routes, is that they employ PbX2 (X = Cl, Br, or I) salts as both lead and halide precursors. This imposes restrictions on being able to precisely tune the amount of reaction species and, consequently, on being able to regulate the composition of the final NCs. In order to overcome this issue, we show here that benzoyl halides can be efficiently used as halide sources to be injected in a solution of metal cations (mainly in the form of metal carboxylates) for the synthesis of APbX3 NCs (in which A = Cs+, CH3NH3+, or CH(NH2)2+). In this way, it is possible to independently tune the amount of both cations and halide precursors in the synthesis. The APbX3 NCs that were prepared with our protocol show excellent optical properties, such as high photoluminescence quantum yields, low amplified spontaneous emission thresholds, and enhanced stability in air. It is noteworthy that CsPbI3 NCs, which crystallize in the cubic α phase, are stable in air for weeks without any postsynthesis treatment. The improved properties of our CsPbX3 perovskite NCs can be ascribed to the formation of lead halide terminated surfaces, in which Cs cations are replaced by alkylammonium ions. PMID:29378131
Imran, Muhammad; Caligiuri, Vincenzo; Wang, Mengjiao; Goldoni, Luca; Prato, Mirko; Krahne, Roman; De Trizio, Luca; Manna, Liberato
2018-02-21
We propose here a new colloidal approach for the synthesis of both all-inorganic and hybrid organic-inorganic lead halide perovskite nanocrystals (NCs). The main limitation of the protocols that are currently in use, such as the hot injection and the ligand-assisted reprecipitation routes, is that they employ PbX 2 (X = Cl, Br, or I) salts as both lead and halide precursors. This imposes restrictions on being able to precisely tune the amount of reaction species and, consequently, on being able to regulate the composition of the final NCs. In order to overcome this issue, we show here that benzoyl halides can be efficiently used as halide sources to be injected in a solution of metal cations (mainly in the form of metal carboxylates) for the synthesis of APbX 3 NCs (in which A = Cs + , CH 3 NH 3 + , or CH(NH 2 ) 2 + ). In this way, it is possible to independently tune the amount of both cations and halide precursors in the synthesis. The APbX 3 NCs that were prepared with our protocol show excellent optical properties, such as high photoluminescence quantum yields, low amplified spontaneous emission thresholds, and enhanced stability in air. It is noteworthy that CsPbI 3 NCs, which crystallize in the cubic α phase, are stable in air for weeks without any postsynthesis treatment. The improved properties of our CsPbX 3 perovskite NCs can be ascribed to the formation of lead halide terminated surfaces, in which Cs cations are replaced by alkylammonium ions.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-03
...-2009-BT-STD-0018] RIN 1904-AC00 Energy Conservation Program: Energy Conservation Standards for Metal... certain metal halide lamp fixtures. This document announces that the period for submitting comments on the... identify the Framework Document for energy conservation standards for metal halide lamp fixtures and...
PREPARATION OF HALIDES OF PLUTONIUM
Garner, C.S.; Johns, I.B.
1958-09-01
A dry chemical method is described for preparing plutonium halides, which consists in contacting plutonyl nitrate with dry gaseous HCl or HF at an elevated temperature. The addition to the reaction gas of a small quantity of an oxidizing gas or a reducing gas will cause formation of the tetra- or tri-halide of plutonium as desired.
Bulk assembly of organic metal halide nanotubes
Lin, Haoran; Zhou, Chenkun; Tian, Yu; ...
2017-10-16
The organic metal halide hybrids welcome a new member with a one-dimensional (1D) tubular structure. Herein we report the synthesis and characterization of a single crystalline bulk assembly of organic metal halide nanotubes, (C 6H 13N 4) 3Pb 2Br 7. In a metal halide nanotube, six face-sharing metal halide dimers (Pb 2Br 9 5–) connect at the corners to form rings that extend in one dimension, of which the inside and outside surfaces are coated with protonated hexamethylenetetramine (HMTA) cations (C 6H 13N 4 +). This unique 1D tubular structure possesses highly localized electronic states with strong quantum confinement, resultingmore » in the formation of self-trapped excitons that give strongly Stokes shifted broadband yellowish-white emission with a photoluminescence quantum efficiency (PLQE) of ~7%. Finally, having realized single crystalline bulk assemblies of two-dimensional (2D) wells, 1D wires, and now 1D tubes using organic metal halide hybrids, our work significantly advances the research on bulk assemblies of quantum-confined materials.« less
Genetic Control of Methyl Halide Production in Arabidopsis
NASA Astrophysics Data System (ADS)
Rhew, R. C.; Ostergaard, L.; Saltzman, E. S.; Yanofsky, M. F.
2003-12-01
Methyl chloride and methyl bromide are the primary carriers of natural chlorine and bromine to the stratosphere where they catalyze the destruction of ozone, whereas methyl iodide influences aerosol formation and ozone loss in the troposphere. Methyl bromide is also an agricultural fumigant whose use is scheduled to be phased out by international agreement. Despite the economic and environmental importance of these methyl halides, their natural sources and biological production mechanisms are poorly understood. Currently identified sources include oceans, biomass burning, industrial and agricultural use, fuel combustion, salt marshes, wetlands, rice paddies, certain terrestrial plants and fungi, and abiotic processes. We demonstrate that the model plant Arabidopsis thaliana produces and emits methyl halides and that the enzyme primarily responsible for the production is encoded by the HARMLESS TO OZONE LAYER (HOL) gene located on chromosome II. In mutant plants that have a disruption of the HOL gene, methyl halide production is largely eliminated. A phylogenetic analysis using the HOL gene suggests that the ability to produce methyl halides is widespread among vascular plants. This approach provides a genetic basis for understanding and predicting patterns of methyl halide production by plants.
Methods for improved growth of group III nitride semiconductor compounds
Melnik, Yuriy; Chen, Lu; Kojiri, Hidehiro
2015-03-17
Methods are disclosed for growing group III-nitride semiconductor compounds with advanced buffer layer technique. In an embodiment, a method includes providing a suitable substrate in a processing chamber of a hydride vapor phase epitaxy processing system. The method includes forming an AlN buffer layer by flowing an ammonia gas into a growth zone of the processing chamber, flowing an aluminum halide containing precursor to the growth zone and at the same time flowing additional hydrogen halide or halogen gas into the growth zone of the processing chamber. The additional hydrogen halide or halogen gas that is flowed into the growth zone during buffer layer deposition suppresses homogeneous AlN particle formation. The hydrogen halide or halogen gas may continue flowing for a time period while the flow of the aluminum halide containing precursor is turned off.
Mixed-Halide Perovskites with Stabilized Bandgaps.
Xiao, Zhengguo; Zhao, Lianfeng; Tran, Nhu L; Lin, Yunhui Lisa; Silver, Scott H; Kerner, Ross A; Yao, Nan; Kahn, Antoine; Scholes, Gregory D; Rand, Barry P
2017-11-08
One merit of organic-inorganic hybrid perovskites is their tunable bandgap by adjusting the halide stoichiometry, an aspect critical to their application in tandem solar cells, wavelength-tunable light emitting diodes (LEDs), and lasers. However, the phase separation of mixed-halide perovskites caused by light or applied bias results in undesirable recombination at iodide-rich domains, meaning open-circuit voltage (V OC ) pinning in solar cells and infrared emission in LEDs. Here, we report an approach to suppress halide redistribution by self-assembled long-chain organic ammonium capping layers at nanometer-sized grain surfaces. Using the stable mixed-halide perovskite films, we are able to fabricate efficient and wavelength-tunable perovskite LEDs from infrared to green with high external quantum efficiencies of up to 5%, as well as linearly tuned V OC from 1.05 to 1.45 V in solar cells.
Potturi, Hima K; Gurung, Ras K; Hou, Yuqing
2012-01-06
Aliphatic or aromatic N,N-disubstituted nitrosamine was generated in fair to excellent yield from the reaction of a secondary or tertiary amine with o-iodoxybenzoic acid (IBX) or o-iodosylbenzoic acid (IBA)/R(4)NX (X = halide) and nitromethane. The product yield was strongly influenced by both the halide of R(4)NX and iodanes. IBX gave a higher yield than IBA, while the halides follow F(-) > Cl(-) > Br(-) ∼ I(-). Nitrous acid formed in situ from nitromethane and IBX (or IBA)/halides is likely responsible for the observed reaction.
Adsorption of halogens on metal surfaces
NASA Astrophysics Data System (ADS)
Andryushechkin, B. V.; Pavlova, T. V.; Eltsov, K. N.
2018-06-01
This paper presents a review of the experimental and theoretical investigations of halogen interaction with metal surfaces. The emphasis was placed on the recent measurements performed with a scanning tunneling microscope in combination with density functional theory calculations. The surface structures formed on metal surface after halogen interaction are classified into three groups: chemisorbed monolayer, surface halide, bulk-like halide. Formation of monolayer structures is described in terms of surface phase transitions. Surface halide phases are considered to be intermediates between chemisorbed halogen and bulk halide. The modern theoretical approaches in studying the dynamics of metal halogenation reactions are also presented.
Code of Federal Regulations, 2010 CFR
2010-01-01
... efficiency of metal halide ballasts. 431.324 Section 431.324 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Metal Halide Lamp Ballasts and Fixtures Test Procedures § 431.324 Uniform test method for the measurement of energy efficiency of metal...
Continuous production of granular or powder Ti, Zr and Hf or their alloy products
White, Jack C.; Oden, Laurance L.
1993-01-01
A continuous process for producing a granular metal selected from the group consisting of Ti, Zr or Hf under conditions that provide orderly growth of the metal free of halide inclusions comprising: a) dissolving a reducing metal selected from the group consisting of Na, Mg, Li or K in their respective halide salts to produce a reducing molten salt stream; b) preparing a second molten salt stream containing the halide salt of Ti, Zr or Hf; c) mixing and reacting the two molten streams of steps a) and b) in a continuous stirred tank reactor; d) wherein steps a) through c) are conducted at a temperature range of from about 800.degree. C. to about 1100.degree. C. so that a weight percent of equilibrium solubility of the reducing metal in its respective halide salt varies from about 1.6 weight percent at about 900.degree. C. to about 14.4 weight percent at about 1062.degree. C.; and wherein a range of concentration of the halide salt of Ti, Zn or Hf in molten halides of Na, Mg, Li or K is from about 1 to about 5 times the concentration of Na, Mg, Li or K; e) placing the reacted molten stream from step c) in a solid-liquid separator to recover an impure granular metal product by decantation, centrifugation, or filtration; and f) removing residual halide salt impurity by vacuum evaporator or inert gas sweep at temperatures from about 850.degree. C. to 1000.degree. C. or cooling the impure granular metal product to ambient temperature and water leaching off the residual metal halide salt.
Nelson, Nya D; Dodson, Lois M; Escudero, Laura; Sukumar, Ann T; Williams, Christopher L; Mihalek, Ivana; Baldan, Alessandro; Baird, Duncan M; Bertuch, Alison A
2018-06-15
TIN2 is central to the shelterin complex, linking the telomeric proteins TRF1 and TRF2 with TPP1/POT1. Mutations in TINF2 , which encodes TIN2, that are found in dyskeratosis congenita (DC) result in very short telomeres and cluster in a region shared by the two TIN2 isoforms, TIN2S (short) and TIN2L (long). Here we show that TIN2L, but not TIN2S, is phosphorylated. TRF2 interacts more with TIN2L than TIN2S, and both the DC cluster and phosphorylation promote this enhanced interaction. The binding of TIN2L, but not TIN2S, is affected by TRF2-F120, which is also required for TRF2's interaction with end processing factors such as Apollo. Conversely, TRF1 interacts more with TIN2S than with TIN2L. A DC-associated mutation further reduces TIN2L-TRF1, but not TIN2S-TRF1, interaction. Cells overexpressing TIN2L or phosphomimetic TIN2L are permissive to telomere elongation, whereas cells overexpressing TIN2S or phosphodead TIN2L are not. Telomere lengths are unchanged in cell lines in which TIN2L expression has been eliminated by clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-mediated mutation. These results indicate that TIN2 isoforms are biochemically and functionally distinguishable and that shelterin composition could be fundamentally altered in patients with TINF2 mutations. Copyright © 2018 Nelson et al.
Non-hydrolytic metal oxide films for perovskite halide overcoating and stabilization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martinson, Alex B.; Kim, In Soo
A method of protecting a perovskite halide film from moisture and temperature includes positioning the perovskite halide film in a chamber. The chamber is maintained at a temperature of less than 200 degrees Celsius. An organo-metal compound is inserted into the chamber. A non-hydrolytic oxygen source is subsequently inserted into the chamber. The inserting of the organo-metal compound and subsequent inserting of the non-hydrolytic oxygen source into the chamber is repeated for a predetermined number of cycles. The non-hydrolytic oxygen source and the organo-metal compound interact in the chamber to deposit a non-hydrolytic metal oxide film on perovskite halide film.more » The non-hydrolytic metal oxide film protects the perovskite halide film from relative humidity of greater than 35% and a temperature of greater than 150 degrees Celsius, respectively.« less
Molecular dynamics simulations of the surface tension and structure of salt solutions and clusters.
Sun, Lu; Li, Xin; Hede, Thomas; Tu, Yaoquan; Leck, Caroline; Ågren, Hans
2012-03-15
Sodium halides, which are abundant in sea salt aerosols, affect the optical properties of aerosols and are active in heterogeneous reactions that cause ozone depletion and acid rain problems. Interfacial properties, including surface tension and halide anion distributions, are crucial issues in the study of the aerosols. We present results from molecular dynamics simulations of water solutions and clusters containing sodium halides with the interatomic interactions described by a conventional force field. The simulations reproduce experimental observations that sodium halides increase the surface tension with respect to pure water and that iodide anions reach the outermost layer of water clusters or solutions. It is found that the van der Waals interactions have an impact on the distribution of the halide anions and that a conventional force field with optimized parameters can model the surface tension of the salt solutions with reasonable accuracy. © 2012 American Chemical Society
Carlsten, R.W.; Nissen, D.A.
1973-03-06
The patent describes an improved thermal battery whose novel design eliminates various disadvantages of previous such devices. Its major features include a halide cathode, a solid metal halide electrolyte which has a substantially greater electrical conductance after a phase transition at some temperature, and a means for heating its electrochemical cells to activation temperature.
Nuclear radiation-warning detector that measures impedance
Savignac, Noel Felix; Gomez, Leo S; Yelton, William Graham; Robinson, Alex; Limmer, Steven
2013-06-04
This invention is a nuclear radiation-warning detector that measures impedance of silver-silver halide on an interdigitated electrode to detect light or radiation comprised of alpha particles, beta particles, gamma rays, X rays, and/or neutrons. The detector is comprised of an interdigitated electrode covered by a layer of silver halide. After exposure to alpha particles, beta particles, X rays, gamma rays, neutron radiation, or light, the silver halide is reduced to silver in the presence of a reducing solution. The change from the high electrical resistance (impedance) of silver halide to the low resistance of silver provides the radiation warning that detected radiation levels exceed a predetermined radiation dose threshold.
Alkali metal and alkali earth metal gadolinium halide scintillators
Bourret-Courchesne, Edith; Derenzo, Stephen E.; Parms, Shameka; Porter-Chapman, Yetta D.; Wiggins, Latoria K.
2016-08-02
The present invention provides for a composition comprising an inorganic scintillator comprising a gadolinium halide, optionally cerium-doped, having the formula A.sub.nGdX.sub.m:Ce; wherein A is nothing, an alkali metal, such as Li or Na, or an alkali earth metal, such as Ba; X is F, Br, Cl, or I; n is an integer from 1 to 2; m is an integer from 4 to 7; and the molar percent of cerium is 0% to 100%. The gadolinium halides or alkali earth metal gadolinium halides are scintillators and produce a bright luminescence upon irradiation by a suitable radiation.
Metal-halide mixtures for latent heat energy storage
NASA Technical Reports Server (NTRS)
Chen, K.; Manvi, R.
1981-01-01
Alkali metal and alkali halide mixtures are identified which may be suitable for thermal energy storage at temperatures above 600 C. The use of metal-halides is appropriate because of their tendency to form two immiscible melts with a density difference, which reduces scale formation and solidification on heat transfer surfaces. Also, the accumulation of phase change material along the melt interface is avoided by the self-dispersing characteristic of some metal-halides, in particular Sr-SrCl2, Ba-BaCl2, and Ba-BaBr2 mixtures. Further advantages lie in their high thermal conductivities, ability to cope with thermal shock, corrosion inhibition, and possibly higher energy densities.
Process for oxidation of hydrogen halides to elemental halogens
Lyke, Stephen E.
1992-01-01
An improved process for generating an elemental halogen selected from chlorine, bromine or iodine, from a corresponding hydrogen halide by absorbing a molten salt mixture, which includes sulfur, alkali metals and oxygen with a sulfur to metal molar ratio between 0.9 and 1.1 and includes a dissolved oxygen compound capable of reacting with hydrogen halide to produce elemental halogen, into a porous, relatively inert substrate to produce a substrate-supported salt mixture. Thereafter, the substrate-supported salt mixture is contacted (stage 1) with a hydrogen halide while maintaining the substrate-supported salt mixture during the contacting at an elevated temperature sufficient to sustain a reaction between the oxygen compound and the hydrogen halide to produce a gaseous elemental halogen product. This is followed by purging the substrate-supported salt mixture with steam (stage 2) thereby recovering any unreacted hydrogen halide and additional elemental halogen for recycle to stage 1. The dissolved oxygen compound is regenerated in a high temperature (stage 3) and an optical intermediate temperature stage (stage 4) by contacting the substrate-supported salt mixture with a gas containing oxygen whereby the dissolved oxygen compound in the substrate-supported salt mixture is regenerated by being oxidized to a higher valence state.
Effect of Halide Composition on the Photochemical Stability of Perovskite Photovoltaic Materials.
Misra, Ravi K; Ciammaruchi, Laura; Aharon, Sigalit; Mogilyansky, Dmitry; Etgar, Lioz; Visoly-Fisher, Iris; Katz, Eugene A
2016-09-22
The photochemical stability of encapsulated films of mixed halide perovskites with a range of MAPb(I 1-x Br x ) 3 (MA=methylammonium) compositions (solid solutions) was investigated under accelerated stressing using concentrated sunlight. The relevance of accelerated testing to standard operational conditions of solar cells was confirmed by comparison to degradation experiments under outdoor sunlight exposure. We found that MAPbBr 3 films exhibited no degradation, while MAPbI 3 and mixed halide MAPb(I 1-x Br x ) 3 films decomposed yielding crystallization of inorganic PbI 2 accompanied by degradation of the perovskite solar light absorption, with faster absorption degradation in mixed halide films. The crystal coherence length was found to correlate with the stability of the films. We postulate that the introduction of Br into the mixed halide solid solution stressed its structure and induced more structural defects and/or grain boundaries compared to pure halide perovskites, which might be responsible for the accelerated degradation. Hence, the cause for accelerated degradation may be the increased defect density rather than the chemical composition of the perovskite materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Baesman, S.M.; Miller, L.G.
2005-01-01
Large carbon kinetic isotope effects (KIEs) were measured for reactions of methyl bromide (MeBr), methyl chloride (MeCl), and methyl iodide (MeI) with various nucleophiles at 287 and 306 K in aqueous solutions. Rates of reaction of MeBr and MeI with H2O (neutral hydrolysis) or Cl- (halide substitution) were consistent with previous measurements. Hydrolysis rates increased with increasing temperature or pH (base hydrolysis). KIEs for hydrolysis were 51 ?? 6??? for MeBr and 38 ?? 8??? for MeI. Rates of halide substitution increased with increasing temperature and greater reactivity of the attacking nucleophile, with the fastest reaction being that of MeI with Br-. KIEs for halide substitution were independent of temperature but varied with the reactant methyl halide and the attacking nucleophile. KIEs were similar for MeBr substitution with Cl- and MeCl substitution with Br- (57 ?? 5 and 60 ?? 9??? respectively). The KIE for halide exchange of MeI was lower overall (33 ?? 8??? and was greater for substitution with Br- (46 ?? 6???) than with Cl- (29 ?? 6???). ?? Springer Science + Business Media, Inc. 2005.
Rationalizing the light-induced phase separation of mixed halide organic-inorganic perovskites.
Draguta, Sergiu; Sharia, Onise; Yoon, Seog Joon; Brennan, Michael C; Morozov, Yurii V; Manser, Joseph S; Kamat, Prashant V; Schneider, William F; Kuno, Masaru
2017-08-04
Mixed halide hybrid perovskites, CH 3 NH 3 Pb(I 1-x Br x ) 3 , represent good candidates for low-cost, high efficiency photovoltaic, and light-emitting devices. Their band gaps can be tuned from 1.6 to 2.3 eV, by changing the halide anion identity. Unfortunately, mixed halide perovskites undergo phase separation under illumination. This leads to iodide- and bromide-rich domains along with corresponding changes to the material's optical/electrical response. Here, using combined spectroscopic measurements and theoretical modeling, we quantitatively rationalize all microscopic processes that occur during phase separation. Our model suggests that the driving force behind phase separation is the bandgap reduction of iodide-rich phases. It additionally explains observed non-linear intensity dependencies, as well as self-limited growth of iodide-rich domains. Most importantly, our model reveals that mixed halide perovskites can be stabilized against phase separation by deliberately engineering carrier diffusion lengths and injected carrier densities.Mixed halide hybrid perovskites possess tunable band gaps, however, under illumination they undergo phase separation. Using spectroscopic measurements and theoretical modelling, Draguta and Sharia et al. quantitatively rationalize the microscopic processes that occur during phase separation.
Perovskite Solar Cells for High-Efficiency Tandems
DOE Office of Scientific and Technical Information (OSTI.GOV)
McGehee, Michael; Buonassisi, Tonio
The first monolithic perovskite/silicon tandem was made with a diffused silicon p-n junction, a tunnel junction made of n ++ hydrogenated amorphous silicon, a titania electron transport layer, a methylammonium lead iodide absorber, and a Spiro-OMeTAD hole transport layer (HTL). The power conversion efficiency (PCE) was only 13.7% due to excessive parasitic absorption of light in the HTL, limiting the matched current density to 11.5 mA/cm 2. Werner et al. 15 raised the PCE to a record 21.2% by switching to a silicon heterojunction bottom cell and carefully tuning layer thicknesses to achieve lower optical loss and a higher currentmore » density of 15.9 mA/cm 2. It is clear from these reports that minimizing parasitic absorption in the window layers is crucial to achieving higher current densities and efficiencies in monolithic tandems. To this end, the window layers through which light first passes before entering the perovskite and silicon absorber materials must be highly transparent. The front electrode must also be conductive to carry current laterally across the top of the device. Indium tin oxide (ITO) is widely utilized as a transparent electrode in optoelectronic devices such as flat-panel displays, smart windows, organic light-emitting diodes, and solar cells due to its high conductivity and broadband transparency. ITO is typically deposited through magnetron sputtering; however, the high kinetic energy of sputtered particles can damage underlying layers. In perovskite solar cells, a sputter buffer layer is required to protect the perovskite and organic carrier extraction layers from damage during sputter deposition. The ideal buffer layer should also be energetically well aligned so as to act as a carrier-selective contact, have a wide bandgap to enable high optical transmission, and have no reaction with the halides in the perovskite. Additionally, this buffer layer should act as a diffusion barrier layer to prevent both organic cation evolution and moisture penetration to overcome the often-reported thermal and environmental instability of metal halide perovskites. Previous perovskite-containing tandems utilized molybdenum oxide (MoO x) as a sputter buffer layer, but this has raised concerns over long-term stability, as the iodide in the perovskite can chemically react with MoO x. Mixed-cation perovskite solar cells have consistently outperformed their single-cation counterparts. The first perovskite device to exceed 20% PCE was fabricated with a mixture of methylammonium (MA) and formamidinium (FA). Recent reports have shown promising results with the introduction of cesium mixtures, enabling high efficiencies with improved photo-, moisture, and thermal stability. The increased moisture and thermal stability are especially important as they broaden the parameter space for processing on top of the perovskite, enabling the deposition of metal oxide contacts through atomic layer deposition (ALD) or chemical vapor deposition (CVD) that may require elevated temperatures or water as a counter reagent. Both titanium dioxide (TiO 2) and tin oxide (SnO 2) have consistently proven to be effective electron-selective contacts for perovskite solar cells and both can be deposited via ALD at temperatures below 150 °C. We introduced a bilayer of SnO 2 and zinc tin oxide (ZTO) that can be deposited by either low-temperature ALD or pulsed-CVD as a window layer with minimal parasitic absorption, efficient electron extraction, and sufficient buffer properties to prevent the organic and perovskite layers from damage during the subsequent sputter deposition of a transparent ITO electrode. We explored pulsed-CVD as a modified ALD process with a continual, rather than purely step-wise, growth component in order to considerably reduce the process time of the SnO 2 deposition process and minimize potential perovskite degradation. These layers, when used in an excellent mixed-cation perovskite solar cell atop a silicon solar cell tuned to the infrared spectrum, enable highly efficient perovskite-silicon tandem solar cells with enhanced thermal and environmental stability.« less
Huang, Guangguang; Wang, Chunlei; Xu, Shuhong; Zong, Shenfei; Lu, Ju; Wang, Zhuyuan; Lu, Changgui; Cui, Yiping
2017-08-01
Unlike widely used postsynthetic halide exchange for CsPbX 3 (X is halide) perovskite nanocrystals (NCs), cation exchange of Pb is of a great challenge due to the rigid nature of the Pb cationic sublattice. Actually, cation exchange has more potential for rendering NCs with peculiar properties. Herein, a novel halide exchange-driven cation exchange (HEDCE) strategy is developed to prepare dually emitting Mn-doped CsPb(Cl/Br) 3 NCs via postsynthetic replacement of partial Pb in preformed perovskite NCs. The basic idea for HEDCE is that the partial cation exchange of Pb by Mn has a large probability to occur as a concomitant result for opening the rigid halide octahedron structure around Pb during halide exchange. Compared to traditional ionic exchange, HEDCE is featured by proceeding of halide exchange and cation exchange at the same time and lattice site. The time and space requirements make only MnCl 2 molecules (rather than mixture of Mn and Cl ions) capable of doping into perovskite NCs. This special molecular doping nature results in a series of unusual phenomenon, including long reaction time, core-shell structured mid states with triple emission bands, and dopant molecules composition-dependent doping process. As-prepared dual-emitting Mn-doped CsPb(Cl/Br) 3 NCs are available for ratiometric temperature sensing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Oxidation of hydrogen halides to elemental halogens
Rohrmann, Charles A.; Fullam, Harold T.
1985-01-01
A process for oxidizing hydrogen halides having substantially no sulfur impurities by means of a catalytically active molten salt is disclosed. A mixture of the subject hydrogen halide and an oxygen bearing gas is contacted with a molten salt containing an oxidizing catalyst and alkali metal normal sulfates and pyrosulfates to produce an effluent gas stream rich in the elemental halogen and substantially free of sulfur oxide gases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sutter-Fella, Carolin M.; Li, Yanbo; Cefarin, Nicola
Organo-lead halide perovskites have recently attracted great interest for potential applications in thin-film photovoltaics and optoelectronics. Herein, we present a protocol for the fabrication of this material via the low-pressure vapor assisted solution process (LP-VASP) method, which yields ~19% power conversion efficiency in planar heterojunction perovskite solar cells. First, we report the synthesis of methylammonium iodide (CH 3NH 3I) and methylammonium bromide (CH 3NH 3Br) from methylamine and the corresponding halide acid (HI or HBr). Then, we describe the fabrication of pinhole-free, continuous methylammonium-lead halide perovskite (CH 3NH 3PbX 3 with X = I, Br, Cl and their mixture) filmsmore » with the LP-VASP. This process is based on two steps: i) spin-coating of a homogenous layer of lead halide precursor onto a substrate, and ii) conversion of this layer to CH 3NH 3PbI 3-xBr x by exposing the substrate to vapors of a mixture of CH 3NH 3I and CH 3NH 3Br at reduced pressure and 120 °C. Through slow diffusion of the methylammonium halide vapor into the lead halide precursor, we achieve slow and controlled growth of a continuous, pinhole-free perovskite film. The LP-VASP allows synthetic access to the full halide composition space in CH 3NH 3PbI 3-xBr x with 0 ≤ x ≤ 3. Depending on the composition of the vapor phase, the bandgap can be tuned between 1.6 eV ≤ E g ≤ 2.3 eV. In addition, by varying the composition of the halide precursor and of the vapor phase, we can also obtain CH 3NH 3PbI 3-xCl x. Films obtained from the LP-VASP are reproducible, phase pure as confirmed by X-ray diffraction measurements, and show high photoluminescence quantum yield. The process does not require the use of a glovebox.« less
Sutter-Fella, Carolin M.; Li, Yanbo; Cefarin, Nicola; ...
2017-09-08
Organo-lead halide perovskites have recently attracted great interest for potential applications in thin-film photovoltaics and optoelectronics. Herein, we present a protocol for the fabrication of this material via the low-pressure vapor assisted solution process (LP-VASP) method, which yields ~19% power conversion efficiency in planar heterojunction perovskite solar cells. First, we report the synthesis of methylammonium iodide (CH 3NH 3I) and methylammonium bromide (CH 3NH 3Br) from methylamine and the corresponding halide acid (HI or HBr). Then, we describe the fabrication of pinhole-free, continuous methylammonium-lead halide perovskite (CH 3NH 3PbX 3 with X = I, Br, Cl and their mixture) filmsmore » with the LP-VASP. This process is based on two steps: i) spin-coating of a homogenous layer of lead halide precursor onto a substrate, and ii) conversion of this layer to CH 3NH 3PbI 3-xBr x by exposing the substrate to vapors of a mixture of CH 3NH 3I and CH 3NH 3Br at reduced pressure and 120 °C. Through slow diffusion of the methylammonium halide vapor into the lead halide precursor, we achieve slow and controlled growth of a continuous, pinhole-free perovskite film. The LP-VASP allows synthetic access to the full halide composition space in CH 3NH 3PbI 3-xBr x with 0 ≤ x ≤ 3. Depending on the composition of the vapor phase, the bandgap can be tuned between 1.6 eV ≤ E g ≤ 2.3 eV. In addition, by varying the composition of the halide precursor and of the vapor phase, we can also obtain CH 3NH 3PbI 3-xCl x. Films obtained from the LP-VASP are reproducible, phase pure as confirmed by X-ray diffraction measurements, and show high photoluminescence quantum yield. The process does not require the use of a glovebox.« less
Improved catalytic properties of halohydrin dehalogenase by modification of the halide-binding site.
Tang, Lixia; Torres Pazmiño, Daniel E; Fraaije, Marco W; de Jong, René M; Dijkstra, Bauke W; Janssen, Dick B
2005-05-03
Halohydrin dehalogenase (HheC) from Agrobacterium radiobacter AD1 catalyzes the dehalogenation of vicinal haloalcohols by an intramolecular substitution reaction, resulting in the formation of the corresponding epoxide, a halide ion, and a proton. Halide release is rate-limiting during the catalytic cycle of the conversion of (R)-p-nitro-2-bromo-1-phenylethanol by the enzyme. The recent elucidation of the X-ray structure of HheC showed that hydrogen bonds between the OH group of Tyr187 and between the Odelta1 atom of Asn176 and Nepsilon1 atom of Trp249 could play a role in stabilizing the conformation of the halide-binding site. The possibility that these hydrogen bonds are important for halide binding and release was studied using site-directed mutagenesis. Steady-state kinetic studies revealed that mutant Y187F, which has lost both hydrogen bonds, has a higher catalytic activity (k(cat)) with two of the three tested substrates compared to the wild-type enzyme. Mutant W249F also shows an enhanced k(cat) value with these two substrates, as well as a remarkable increase in enantiopreference for (R)-p-nitro-2-bromo-1-phenylethanol. In case of a mutation at position 176 (N176A and N176D), a 1000-fold lower catalytic efficiency (k(cat)/K(m)) was obtained, which is mainly due to an increase of the K(m) value of the enzyme. Pre-steady-state kinetic studies showed that a burst of product formation precedes the steady state, indicating that halide release is still rate-limiting for mutants Y187F and W249F. Stopped-flow fluorescence experiments revealed that the rate of halide release is 5.6-fold higher for the Y187F mutant than for the wild-type enzyme and even higher for the W249F enzyme. Taken together, these results show that the disruption of two hydrogen bonds around the halide-binding site increases the rate of halide release and can enhance the overall catalytic activity of HheC.
Rationalizing the light-induced phase separation of mixed halide organic–inorganic perovskites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Draguta, Sergiu; Sharia, Onise; Yoon, Seog Joon
Mixed halide hybrid perovskites, CH 3NH 3Pb(I 1-xBrx) 3' represent good candidates for lowcost, high efficiency photovoltaic, and light-emitting devices. Their band gaps can be tuned from 1.6 to 2.3 eV, by changing the halide anion identity. Unfortunately, mixed halide perovskites undergo phase separation under illumination. This leads to iodide- and bromide-rich domains along with corresponding changes to the material’s optical/electrical response. Here, using combined spectroscopic measurements and theoretical modeling, we quantitatively rationalize all microscopic processes that occur during phase separation. Our model suggests that the driving force behind phase separation is the bandgap reduction of iodiderich phases. It additionallymore » explains observed non-linear intensity dependencies, as well as self-limited growth of iodide-rich domains. Most importantly, our model reveals that mixed halide perovskites can be stabilized against phase separation by deliberately engineering carrier diffusion lengths and injected carrier densities.« less
Rationalizing the light-induced phase separation of mixed halide organic–inorganic perovskites
Draguta, Sergiu; Sharia, Onise; Yoon, Seog Joon; ...
2017-08-04
Mixed halide hybrid perovskites, CH 3NH 3Pb(I 1-xBrx) 3' represent good candidates for lowcost, high efficiency photovoltaic, and light-emitting devices. Their band gaps can be tuned from 1.6 to 2.3 eV, by changing the halide anion identity. Unfortunately, mixed halide perovskites undergo phase separation under illumination. This leads to iodide- and bromide-rich domains along with corresponding changes to the material’s optical/electrical response. Here, using combined spectroscopic measurements and theoretical modeling, we quantitatively rationalize all microscopic processes that occur during phase separation. Our model suggests that the driving force behind phase separation is the bandgap reduction of iodiderich phases. It additionallymore » explains observed non-linear intensity dependencies, as well as self-limited growth of iodide-rich domains. Most importantly, our model reveals that mixed halide perovskites can be stabilized against phase separation by deliberately engineering carrier diffusion lengths and injected carrier densities.« less
Synthesis and Characterization of Tin(IV) Oxide Obtained by Chemical Vapor Deposition Method
NASA Astrophysics Data System (ADS)
Nagirnyak, Svitlana V.; Lutz, Victoriya A.; Dontsova, Tatiana A.; Astrelin, Igor M.
2016-07-01
The effect of precursors on the characteristics of tin oxide obtained by chemical vapor deposition (CVD) method was investigated. The synthesis of nanosized tin(IV) oxide was carried out with the use of two different precursors: tin(II) oxalate obtained using tin chloride(II) and oxalic acid; tin(II) oxalate obtained using tin chloride(II); and ammonium oxalate. The synthesized tin(IV) oxide samples were studied by electron microscopy, X-ray diffraction and optical spectra. The lattice parameters of tin(IV) oxide samples were defined, the bandgap of samples were calculated.
METHOD OF PREPARING METAL HALIDES
Hendrickson, A.V.
1958-11-18
The conversion of plutonium halides from plutonium peroxide can be done by washing the peroxide with hydrogen peroxide, drying the peroxide, passing a dry gaseous hydrohalide over the surface of the peroxide at a temperature of about lOO icient laborato C until the reaction rate has stabillzed, and then ralsing the reaction temperature to between 400 and 600 icient laborato C until the conversion to plutonium halide is substantially complete.
Anti-perovskite solid electrolyte compositions
Zhao, Yusheng; Daemen, Luc Louis
2015-12-26
Solid electrolyte antiperovskite compositions for batteries, capacitors, and other electrochemical devices have chemical formula Li.sub.3OA, Li.sub.(3-x)M.sub.x/2OA, Li.sub.(3-x)N.sub.x/3OA, or LiCOX.sub.zY.sub.(1-z), wherein M and N are divalent and trivalent metals respectively and wherein A is a halide or mixture of halides, and X and Y are halides.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Determination Procedure for Metal Halide Lamp Ballasts C Appendix C to Subpart S of Part 431 Energy DEPARTMENT... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures Pt. 431, Subpt. S, App. C Appendix C to Subpart S of Part..., and n1 is the total number of tests. (c) Compute the standard deviation (S1) of the measured energy...
Kempe, André; Lackner, Maximilian
2016-01-01
The influence of aqueous halide solutions on collagen coatings was tested. The effects on resistance against indentation/penetration on adhesion forces were measured by atomic force microscopy (AFM) and the change of Young's modulus of the coating was derived. Comparative measurements over time were conducted with halide solutions of various concentrations. Physical properties of the mesh-like coating generally showed large variability. Starting with a compact set of physical properties, data disperse after minutes. A trend of increase in elasticity and permeability was found for all halide solutions. These changes were largest in NaI, displaying a logical trend with ion size. However a correlation with concentration was not measured. Adhesion properties were found to be independent of mechanical properties. The paper also presents practical experience for AFM measurements of soft tissue under liquids, particularly related to data evaluation. The weakening in physical strength found after exposure to halide solutions may be interpreted as widening of the network structure or change in the chemical properties in part of the collagen fibres (swelling). In order to design customized surface coatings at optimized conditions also for medical applications, halide solutions might be used as agents with little impact on the safety of patients. PMID:27721994
International strategic minerals inventory summary report; tin
Sutphin, D.M.; Sabin, A.E.; Reed, B.L.
1990-01-01
The International Strategic Minerals Inventory tin inventory contains records for 56 major tin deposits and districts in 21 countries. These countries accounted for 98 percent of the 10 million metric tons of tin produced in the period 1934-87. Tin is a good alloying metal and is generally nontoxic, and its chief uses are as tinplate for tin cans and as solder in electronics. The 56 locations consist of 39 lode deposits and 17 placers and contain almost 7.5 million metric tons of tin in identified economic resources (R1E) and another 1.5 million metric tons of tin in other resource categories. Most of these resources are in major deposits that have been known for over a hundred years. Lode deposits account for 44 percent of the R1E and 87 percent of the resources in other categories. Placer deposits make up the remainder. Low-income and middle-income countries, including Bolivia and Brazil and countries along the Southeast Asian Tin Belt such as Malaysia, Thailand, and Indonesia account for 91 percent of the R1E resources of tin and for 61 percent of resources in other categories. The United States has less than 0.05 percent of the world's tin R1E in major deposits. Available data suggest that the Soviet Union may have about 4 percent of resources in this category. The industrial market economy countries of the United States, Japan, Federal Republic of Germany, and the United Kingdom are major consumers of tin, whereas the major tin-producing countries generally consume little tin. The Soviet Union and China are both major producers and consumers of tin. At the end of World War II, the four largest tin-producing countries (Bolivia, the Belgian Congo (Zaire), Nigeria, and Malaysia) produced over 80 percent of the world's tin. In 1986, the portion of production from the four largest producers (Malaysia, Brazil, Soviet Union, Indonesia) declined to about 55 percent, while the price of tin rose from about $1,500 to $18,000 per metric ton. In response to tin shortages during World War II, the United States began stockpiling refined tin metal from approximately 1946 to 1953 to ensure a strategic supply in the event of another war. Since World War II, there have been six International Tin Agreements to maintain price and supply stability between tin producers and consumers. Artificially high prices set by the tin-producing members and a tin glut brought on by independent producers like Brazil caused the collapse of the world tin market in late 1985; the International Tin Council exhausted its credit to support the market price. By the year 2025, Bolivia's underground lode mines will likely have insignificant production, as will those in the United Kingdom. Tin mines in the Southeast Asian Tin Belt will still be active. Brazil, which has risen from the eighth-ranked tin-producing country in 1982 to the largest producer in 1988, will likely be a major influence on world tin production well into the 21st century. The future mining activity of deposits presently inactive in Australia is impossible to predict.
40 CFR 421.290 - Applicability: Description of the secondary tin subcategory.
Code of Federal Regulations, 2012 CFR
2012-07-01
... secondary tin subcategory. 421.290 Section 421.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Tin Subcategory § 421.290 Applicability: Description of the secondary tin subcategory. The provisions of this subpart are applicable to discharges resulting from the production of tin at secondary tin...
40 CFR 421.290 - Applicability: Description of the secondary tin subcategory.
Code of Federal Regulations, 2010 CFR
2010-07-01
... secondary tin subcategory. 421.290 Section 421.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Tin Subcategory § 421.290 Applicability: Description of the secondary tin subcategory. The provisions of this subpart are applicable to discharges resulting from the production of tin at secondary tin...
40 CFR 421.290 - Applicability: Description of the secondary tin subcategory.
Code of Federal Regulations, 2013 CFR
2013-07-01
... secondary tin subcategory. 421.290 Section 421.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Tin Subcategory § 421.290 Applicability: Description of the secondary tin subcategory. The provisions of this subpart are applicable to discharges resulting from the production of tin at secondary tin...
40 CFR 421.290 - Applicability: Description of the secondary tin subcategory.
Code of Federal Regulations, 2011 CFR
2011-07-01
... secondary tin subcategory. 421.290 Section 421.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Tin Subcategory § 421.290 Applicability: Description of the secondary tin subcategory. The provisions of this subpart are applicable to discharges resulting from the production of tin at secondary tin...
40 CFR 421.290 - Applicability: Description of the secondary tin subcategory.
Code of Federal Regulations, 2014 CFR
2014-07-01
... secondary tin subcategory. 421.290 Section 421.290 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Tin Subcategory § 421.290 Applicability: Description of the secondary tin subcategory. The provisions of this subpart are applicable to discharges resulting from the production of tin at secondary tin...
Device simulation of lead-free CH3NH3SnI3 perovskite solar cells with high efficiency
NASA Astrophysics Data System (ADS)
Du, Hui-Jing; Wang, Wei-Chao; Zhu, Jian-Zhuo
2016-10-01
The lead-free perovskite solar cells (PSCs) have drawn a great deal of research interest due to the Pb toxicity of the lead halide perovskite. CH3NH3SnI3 is a viable alternative to CH3NH3PbX3, because it has a narrower band gap of 1.3 eV and a wider visible absorption spectrum than the lead halide perovskite. The progress of fabricating tin iodide PSCs with good stability has stimulated the studies of these CH3NH3SnI3 based cells greatly. In the paper, we study the influences of various parameters on the solar cell performance through theoretical analysis and device simulation. It is found in the simulation that the solar cell performance can be improved to some extent by adjusting the doping concentration of the perovskite absorption layer and the electron affinity of the buffer and HTM, while the reduction of the defect density of the perovskite absorption layer significantly improves the cell performance. By further optimizing the parameters of the doping concentration (1.3× 1016 cm-3) and the defect density (1× 1015 cm-3) of perovskite absorption layer, and the electron affinity of buffer (4.0 eV) and HTM (2.6 eV), we finally obtain some encouraging results of the J sc of 31.59 mA/cm2, V oc of 0.92 V, FF of 79.99%, and PCE of 23.36%. The results show that the lead-free CH3NH3SnI3 PSC is a potential environmentally friendly solar cell with high efficiency. Improving the Sn2 + stability and reducing the defect density of CH3NH3SnI3 are key issues for the future research, which can be solved by improving the fabrication and encapsulation process of the cell. Project supported by the Graduate Student Education Teaching Reform Project, China (Grant No. JG201512) and the Young Teachers Research Project of Yanshan University, China (Grant No. 13LGB028).
The thermo-elastic instability model of melting of alkali halides in the Debye approximation
NASA Astrophysics Data System (ADS)
Owens, Frank J.
2018-05-01
The Debye model of lattice vibrations of alkali halides is used to show that there is a temperature below the melting temperature where the vibrational pressure exceeds the electrostatic pressure. The onset temperature of this thermo-elastic instability scales as the melting temperature of NaCl, KCl, and KBr, suggesting its role in the melting of the alkali halides in agreement with a previous more rigorous model.
The role of halide ions on the electrochemical behaviour of iron in alkali solutions
NASA Astrophysics Data System (ADS)
Begum, S. Nathira; Muralidharan, V. S.; Basha, C. Ahmed
2008-02-01
Active dissolution and passivation of transition metals in alkali solutions is of technological importance in batteries. The performance of alkaline batteries is decided by the presence of halides as they influence passivation. Cyclic voltammetric studies were carried out on iron in different sodium hydroxide solutions in presence of halides. In alkali solutions iron formed hydroxo complexes and their polymers in the interfacial diffusion layer. With progress of time they formed a cation selective layer. The diffusion layer turned into bipolar ion selective layer consisted of halides, a selective inner sublayer to the metal side and cation selective outer layer to the solution side. At very high anodic potentials, dehydration and deprotonation led to the conversion of salt layer into an oxide.
Boogaard, Peter J; Boisset, Michel; Blunden, Steve; Davies, Scot; Ong, Teng Jin; Taverne, Jean-Pierre
2003-12-01
Tin is present in low concentrations in most canned foods and beverages, the highest levels being found in products packaged in unlacquered or partially lacquered tinplate cans. A limited number of case-reports of acute gastrointestinal disorders after consumption of food containing 100-500 mg/kg tin have been reported, but these reports suffer many insufficiencies. Controlled clinical studies on acute effects of tin migrated from packaging suggest a threshold concentration for adverse effects (AEs) of >730 mg/kg. Two separate randomised, single-centre, double-blind, crossover studies, enabling comparison of the tolerability of tin added as tin(II) chloride at concentrations of <0.5, 161, 264 and 529 mg/kg in 250 ml tomato juice in 20 volunteers (Study 1) and tin migrated from packaging at concentrations of <0.5, 201 and 267 mg/kg in 250 ml tomato soup in 24 volunteers (Study 2) were carried out. Distribution studies were conducted to get insight in the acute AEs of low molecular weight (<1000 Da) tin species in the soluble fraction of food products. Results show that the chemical form of tin and not the elemental concentration per se determines the severity of AEs. A clear dose-response relationship was only observed when tin was added as tin(II) chloride in tomato juice. No clinically significant AEs were reported in Study 2 and comparison of the incidence of tin-related AEs showed no difference between the dose levels (including control). Tin species of low molecular weight in supernatant represented 31-32% of total tin in canned tomato soup versus 56-61% in juice freshly spiked with tin(II) chloride. Differences in the incidence of AEs following administration of tomato juice with 161 and 264 mg of tin per kg and tomato soup with 201 and 267 mg of tin per kg likely results from differences in the concentration of low molecular weight tin species and in the nature of tin complexes formed. The results of this work demonstrate that tin levels up to 267 mg/kg in canned food cause no AEs in healthy adults and support the currently proposed tin levels of 200 mg/kg and 250 mg/kg for canned beverages and canned foods, respectively, as safe levels for adults in the general population.
Telomere dysfunction and cell survival: roles for distinctTIN2-containing complexes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Sahn-Ho; Davalos, Albert R.; Heo, Seok-Jin
Telomeres are maintained by three DNA binding proteins, TRF1, TRF2 and POT1, and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. These and two other proteins form a soluble complex that may be the core telomere-maintenance complex. It is not clear whether subcomplexes exist or function in vivo. Here, we provide evidence for two TIN2 subcomplexes with distinct functions in human cells. TIN2 ablation by RNA interference caused telomere uncapping and p53-independent cell death in all cells tested. However, we isolated two TIN2 complexes from cell lysates, each selectively sensitive to a TIN2 mutantmore » (TIN2-13, TIN2-15C). In cells with wild-type p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere uncapping and eventual growth arrest. In cells lacking p53 function, TIN215C more than TIN2-13 caused genomic instability and cell death. Thus, TIN2 subcomplexes likely have distinct functions in telomere maintenance, and may provide selective targets for eliminating cells with mutant p53.« less
Lanthanide doped strontium-barium cesium halide scintillators
Bizarri, Gregory; Bourret-Courchesne, Edith; Derenzo, Stephen E.; Borade, Ramesh B.; Gundiah, Gautam; Yan, Zewu; Hanrahan, Stephen M.; Chaudhry, Anurag; Canning, Andrew
2015-06-09
The present invention provides for a composition comprising an inorganic scintillator comprising an optionally lanthanide-doped strontium-barium, optionally cesium, halide, useful for detecting nuclear material.
Copper/amino acid catalyzed cross-couplings of aryl and vinyl halides with nucleophiles.
Ma, Dawei; Cai, Qian
2008-11-18
Copper-assisted Ullmann-type coupling reactions are valuable transformations for organic synthesis. Researchers have extensively applied these reactions in both academic and industrial settings. However, two important issues, the high reaction temperatures (normally above 150 degrees C) and the stoichiometric amounts of copper necessary, have greatly limited the reaction scope. To solve these problems, we and other groups have recently explored the use of special ligands to promote these coupling reactions. We first showed that the structure of alpha-amino acids can accelerate Cu-assisted Ullmann reactions, leading to the coupling reactions of aryl halides and alpha-amino acids at 80-90 degrees C. In response to these encouraging results, we also discovered that an l-proline ligand facilitated the following transformations: (1) coupling of aryl halides with primary amines, cyclic secondary amines, and N-containing heterocycles at 40-90 degrees C; (2) coupling of aryl halides with sulfinic acid salts at 80-95 degrees C; (3) azidation of aryl halides and vinyl halides with sodium azide at 40-95 degrees C; (4) coupling of aryl halides with activated methylene compounds at 25-50 degrees C. In addition, we found that N,N-dimethylglycine as a ligand facilitated Cu-catalyzed biaryl ether formation at 90 degrees C. Moreover, Sonogashira reactions worked in the absence of palladium and phosphine ligands, forming enamides from vinyl halides and amides at temperatures ranging from ambient temperature up to 80 degrees C. Furthermore, we discovered that an ortho-amide group can accelerate some Ullmann-type reactions. This functional group in combination with other ligand effects allowed for aryl amination or biaryl ether formation at ambient temperature. The coupling between aryl halides and activated methylene compounds even proceeded at -45 degrees C to enantioselectively form a quaternary carbon center. Taking advantage of these results, we developed several novel approaches for the synthesis of pharmaceutically important heterocycles: 1,2-disubstituted benzimidazoles, polysubstituted indoles, N-substituted 1,3-dihydrobenzimidazol-2-ones, and substituted 3-acyl oxindoles. Our results demonstrate that an l-proline or N,N-dimethylglycine ligand can facilitate most typical Ullmann-type reactions, with reactions occurring under relatively mild conditions and using only 2-20 mol % copper catalysts. These conveniently available and inexpensive catalytic systems not only accelerate the reactions but also tolerate many more functional groups. Thus, they should find considerable application in organic synthesis.
Kamilli, Robert J.; Kimball, Bryn E.; Carlin, James F.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.
2017-12-19
Tin (Sn) is one of the first metals to be used by humans. Almost without exception, tin is used as an alloy. Because of its hardening effect on copper, tin was used in bronze implements as early as 3500 B.C. The major uses of tin today are for cans and containers, construction materials, transportation materials, and solder. The predominant ore mineral of tin, by far, is cassiterite (SnO2).In 2015, the world’s total estimated mine production of tin was 289,000 metric tons of contained tin. Total world reserves at the end of 2016 were estimated to be 4,700,000 metric tons. China held about 24 percent of the world’s tin reserves and accounted for 38 percent of the world’s 2015 production of tin.The proportion of scrap used in tin production is between 10 and 25 percent. Unlike many metals, tin recycling is relatively efficient, and the fraction of tin in discarded products that get recycled is greater than 50 percent.Only about 20 percent of the world’s identified tin resources occur as primary hydrothermal hard-rock veins, or lodes. These lodes contain predominantly high-temperature minerals and almost invariably occur in close association with silicic, peraluminous granites. About 80 percent of the world’s identified tin resources occur as unconsolidated secondary or placer deposits in riverbeds and valleys or on the sea floor. The largest concentration of both onshore and offshore placers is in the extensive tin belt of Southeast Asia, which stretches from China in the north, through Thailand, Burma (also referred to as Myanmar), and Malaysia, to the islands of Indonesia in the south. Furthermore, tin placers are almost always found closely allied to the granites from which they originate. Other countries with significant tin resources are Australia, Bolivia, and Brazil.Most hydrothermal tin deposits belong to what can be thought of as a superclass of porphyry-greisen deposits. The hydrothermal tin deposits are all characterized by a close spatial, temporal, and genetic association with highly differentiated, peraluminous porphyritic granite intrusions. The intrusions form pegmatites; disseminated ore; parallel or subparallel, greisen-bordered sheeted veins that either cross-cut the intrusion or are peripheral to it; skarns; and (or) limestone replacements that contain different amounts of cassiterite, molybdenite, and wolframite.The tectonic settings of tin-bearing granites are relatively well understood and of limited variety. Tin and tungsten deposits and their associated igneous rocks are found mainly in continental settings.Historically, prospecting for tin has been carried out by the time-honored methods of panning, drilling, trenching, and assaying. Geophysical and geochemical surveys have been employed to cover large areas more rapidly, isolating areas of possible tin deposits so that drilling can be more effective and less costly. Elemental concentrations and relationships of the lithophile elements, especially barium, lithium, niobium, potassium, rubidium, and zirconium, are the most reliable chemical indicators of ore-forming processes and tin-bearing potential.The average human diet includes an intake of about 10 milligrams per day of tin. Ingestion of tin in significantly greater amounts than 10 milligrams per day may lead to a stomach ache, anemia, and liver and kidney problems. Exposure to some organo-tin compounds can interfere with brain and nervous system function and, in severe cases, can cause death. Extended inhalation of tin oxide—an issue mainly for those people who work in the tin industry—results in a higher potential to develop stannosis, which is a mild disease of the lungs caused by the inhalation of tin-bearing dust. Inorganic tin is poorly absorbed by the body, and no evidence exists for the carcinogenicity of metallic tin and tin compounds in humans.Most placer tin deposits are mined by open pit and (or) dredging methods. Mining of alluvial placers in modern streambeds and riverbeds is likely to increase the amount of sediment delivered downstream. This, combined with potential diversion of rivers and streams, may negatively affect downstream ecosystems. Many of the placer deposits located in Burma, Indonesia, Malaysia, and Thailand are located offshore. Most offshore placer tin deposits are mined by dredging methods, which have the potential to negatively affect benthic, midwater, and pelagic ecosystems.In a congressionally mandated U.S. Department of Defense study of strategic minerals published in 2013, tin has the greatest shortfall amount (insufficient supply to meet demand) at \\$416 million; this amount is more than twice that of antimony ($182 million), which is the strategic mineral with the next largest shortfall amount (U.S. Department of Defense, 2013). The United States imported 75 percent of its tin supply in 2015. During the period 2012–15, these imports were from, in descending order of amount imported, Peru, Indonesia, Malaysia, and Bolivia.A promising advancement concerning research into the origin of tin deposits is the recent development of a reliable method of analyzing tin isotopes in cassiterite. Although the mechanism of transport and deposition of tin is fairly well understood, the means by which tin is incorporated into the parent magma at the points of magma generation and ascent needs further investigation.Tin metallogenic provinces worldwide are well known. Consequently, any undiscovered tin deposits will likely be spatially close to known deposits or extensions of the same.
Balcerzyk, Anna; Schmidhammer, Uli; El Omar, Abdel Karim; Jeunesse, Pierre; Larbre, Jean-Philippe; Mostafavi, Mehran
2011-08-25
Recently we measured the amount of the single product, Br(3)(-), of steady-state radiolysis of highly concentrated Br(-) aqueous solutions, and we showed the effect of the direct ionization of Br(-) on the yield of Br(3)(-). Here, we report the first picosecond pulse-probe radiolysis measurements of ionization of highly concentrated Br(-) and Cl(-) aqueous solutions to describe the oxidation mechanism of the halide anions. The transient absorption spectra are reported from 350 to 750 nm on the picosecond range for halide solutions at different concentrations. In the highly concentrated halide solutions, we observed that, due to the presence of Na(+), the absorption band of the solvated electron is shifted to shorter wavelengths, but its decay, taking place during the spur reactions, is not affected within the first 4 ns. The kinetic measurements in the UV reveal the direct ionization of halide ions. The analysis of pulse-probe measurements show that after the electron pulse, the main reactions in solutions containing 1 M of Cl(-) and 2 M of Br(-) are the formation of ClOH(-•) and BrOH(-•), respectively. In contrast, in highly concentrated halide solutions, containing 5 M of Cl(-) and 6 M of Br(-), mainly Cl(2)(-•) and Br(2)(-•) are formed within the electron pulse without formation of ClOH(-•) and BrOH(-•). The results suggest that, not only Br(-) and Cl(-) are directly ionized into Br(•) and Cl(•) by the electron pulse, the halide atoms can also be rapidly generated through the reactions initiated by excitation and ionization of water, such as the prompt oxidation by the hole, H(2)O(+•), generated in the coordination sphere of the anion. © 2011 American Chemical Society
NASA Astrophysics Data System (ADS)
Cheng, Jing; Vianco, Paul T.; Li, James C. M.
2010-05-01
Tin whiskers have been an engineering challenge for over five decades. The mechanism has not been agreed upon thus far. This experiment aimed to identify a mechanism by applying compressive stresses to a tin film evaporated on silicon substrate with an adhesion layer of chromium in between. A phenomenon was observed in which hollow whiskers grew inside depleted areas. Using focused ion beam, the hollow whiskers were found to contain both tin and chromium. At the bottom of the depleted areas, thin tin/tin oxide film remained over the chromium layer. It indicates that tin transport occurred along the interface between tin and chromium layers.
2015-06-01
INVESTIGATION OF HEAVY OXIDE AND ALKALI-HALIDE SCINTILLATORS FOR POTENTIAL USE IN NEUTRON AND GAMMA DETECTION SYSTEMS by Jeremy S. Cadiente June...AND ALKALI- HALIDE SCINTILLATORS FOR POTENTIAL USE IN NEUTRON AND GAMMA DETECTION SYSTEMS 5. FUNDING NUMBERS 6. AUTHOR(S) Jeremy S. Cadiente 7...fast neutron detection efficiencies well over 40%, were investigated for potential use as highly efficient gamma- neutron radiation detectors. The
McNichols, Brett W.; Koubek, Joshua T.; Sellinger, Alan
2017-10-27
Here, we have developed a single step palladium-catalyzed Heck coupling of aryl halides with vinyl phosphonic acid to produce functionalized (E)-styryl phosphonic acids. This pathway utilizes a variety of commercially available aryl halides, vinyl phosphonic acid and Pd(P(tBu) 3) 2 as catalyst. These conditions produce a wide range of styryl phosphonic acids with high purities and good to excellent yields (31–80%).
Transfer Hydro-dehalogenation of Organic Halides Catalyzed by Ruthenium(II) Complex.
You, Tingjie; Wang, Zhenrong; Chen, Jiajia; Xia, Yuanzhi
2017-02-03
A simple and efficient Ru(II)-catalyzed transfer hydro-dehalogenation of organic halides using 2-propanol solvent as the hydride source was reported. This methodology is applicable for hydro-dehalogenation of a variety of aromatic halides and α-haloesters and amides without additional ligand, and quantitative yields were achieved in many cases. The potential synthetic application of this method was demonstrated by efficient gram-scale transformation with catalyst loading as low as 0.5 mol %.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McNichols, Brett W.; Koubek, Joshua T.; Sellinger, Alan
Here, we have developed a single step palladium-catalyzed Heck coupling of aryl halides with vinyl phosphonic acid to produce functionalized (E)-styryl phosphonic acids. This pathway utilizes a variety of commercially available aryl halides, vinyl phosphonic acid and Pd(P(tBu) 3) 2 as catalyst. These conditions produce a wide range of styryl phosphonic acids with high purities and good to excellent yields (31–80%).
Synthesis and luminescence of Mn-doped Cs2AgInCl6 double perovskites.
K, Nila Nandha; Nag, Angshuman
2018-05-17
Metal halide double perovskites (DPs) are being explored as stable and non-toxic alternatives of Pb-halide perovskites. Typically DPs exhibit a wide (>2.5 eV) and/or indirect bandgap, limiting their applications in the visible region. Here we impart the visible-light emission property in direct bandgap Cs2AgInCl6 DPs by doping Mn2+ ions. Synthesis, characterization and luminescence of metal halide double perovskites are reported.
Sladkevich, S; Gun, J; Prikhodchenko, P V; Gutkin, V; Mikhaylov, A A; Novotortsev, V M; Zhu, J X; Yang, D; Hng, H H; Tay, Y Y; Tsakadze, Z; Lev, O
2012-12-07
We describe a new, simple and low-temperature method for ultra-thin coating of graphene oxide (GO) by peroxostannate, tin oxide or a mixture of tin and tin oxide crystallites by different treatments. The technique is environmentally friendly and does not require complicated infrastructure, an autoclave or a microwave. The supported peroxostannate phase is partially converted after drying to crystalline tin oxide with average, 2.5 nm cassiterite crystals. Mild heat treatment yielded full coverage of the reduced graphene oxide by crystalline tin oxide. Extensive heat treatment in vacuum at >500 °C yielded a mixture of elemental tin and cassiterite tin oxide nanoparticles supported on reduced graphene oxide (rGO). The usefulness of the new approach was demonstrated by the preparation of two types of lithium ion anodes: tin oxide-rGO and a mixture of tin oxide and tin coated rGO composites (SnO(2)-Sn-rGO). The electrodes exhibited stable charge/discharge cyclability and high charging capacity due to the intimate contact between the conductive graphene and the very small tin oxide crystallites. The charging/discharging capacity of the anodes exceeded the theoretical capacity predicted based on tin lithiation. The tin oxide coated rGO exhibited higher charging capacity but somewhat lower stability upon extended charge/discharge cycling compared to SnO(2)-Sn-rGO.
Miller, L. B.; Donohoe, S. P.; Jones, M. H.; ...
2015-04-22
This article reports on the testing and comparison of a prototype hydrogen fuel cell light tower (H2LT) and a conventional diesel-powered metal halide light trailer for use in road maintenance and construction activities. The prototype was originally outfitted with plasma lights and then with light-emitting diode (LED) luminaires. Light output and distribution, lighting energy efficiency (i.e., efficacy), power source thermal efficiency, and fuel costs are compared. The metal halide luminaires have 2.2 and 3.1 times more light output than the plasma and LED luminaires, respectively, but they require more power/lumen to provide that output. The LED luminaires have 1.6 timesmore » better light efficacy than either the metal halide or plasma luminaires. The light uniformity ratios produced by the plasma and LED towers are acceptable. The fuel cell thermal efficiency at the power required to operate the plasma lights is 48%, significantly higher than the diesel generator efficiency of 23% when operating the metal halide lights. Due to the increased efficiency of the fuel cell and the LED lighting, the fuel cost per lumen-hour of the H2LT is 62% of the metal halide diesel light tower assuming a kilogram of hydrogen is twice the cost of a gallon of diesel fuel.« less
Intermediate Temperature Fluids Life Tests - Theory
NASA Technical Reports Server (NTRS)
Tarau, Calin; Sarraf, David B.; Locci, Ivan E.; Anderson, William G.
2008-01-01
There are a number of different applications that could use heat pipes or loop heat pipes (LHPs) in the intermediate temperature range of 450 to 750 K, including space nuclear power system radiators, and high temperature electronics cooling. Potential working fluids include organic fluids, elements, and halides, with halides being the least understood, with only a few life tests conducted. Potential envelope materials for halide working fluids include pure aluminum, aluminum alloys, commercially pure (CP) titanium, titanium alloys, and corrosion resistant superalloys. Life tests were conducted with three halides (AlBr3, SbBr3, and TiCl4) and water in three different envelopes: two aluminum alloys (Al-5052, Al-6061) and Cp-2 titanium. The AlBr3 attacked the grain boundaries in the aluminum envelopes, and formed TiAl compounds in the titanium. The SbBr3 was incompatible with the only envelope material that it was tested with, Al-6061. TiCl4 and water were both compatible with CP2-titanium. A theoretical model was developed that uses electromotive force differences to predict the compatibility of halide working fluids with envelope materials. This theory predicts that iron, nickel, and molybdenum are good envelope materials, while aluminum and titanium halides are good working fluids. The model is in good agreement with results form previous life tests, as well as the current life tests.
Exhaustive thin-layer cyclic voltammetry for absolute multianalyte halide detection.
Cuartero, Maria; Crespo, Gastón A; Ghahraman Afshar, Majid; Bakker, Eric
2014-11-18
Water analysis is one of the greatest challenges in the field of environmental analysis. In particular, seawater analysis is often difficult because a large amount of NaCl may mask the determination of other ions, i.e., nutrients, halides, and carbonate species. We demonstrate here the use of thin-layer samples controlled by cyclic voltammetry to analyze water samples for chloride, bromide, and iodide. The fabrication of a microfluidic electrochemical cell based on a Ag/AgX wire (working electrode) inserted into a tubular Nafion membrane is described, which confines the sample solution layer to less than 15 μm. By increasing the applied potential, halide ions present in the thin-layer sample (X(-)) are electrodeposited on the working electrode as AgX, while their respective counterions are transported across the perm-selective membrane to an outer solution. Thin-layer cyclic voltammetry allows us to obtain separated peaks in mixed samples of these three halides, finding a linear relationship between the halide concentration and the corresponding peak area from about 10(-5) to 0.1 M for bromide and iodide and from 10(-4) to 0.6 M for chloride. This technique was successfully applied for the halide analysis in tap, mineral, and river water as well as seawater. The proposed methodology is absolute and potentially calibration-free, as evidenced by an observed 2.5% RSD cell to cell reproducibility and independence from the operating temperature.
Xiao, Zewen; Du, Ke-Zhao; Meng, Weiwei; Mitzi, David B; Yan, Yanfa
2017-09-25
Recently, Cu I - and Ag I -based halide double perovskites have been proposed as promising candidates for overcoming the toxicity and instability issues inherent within the emerging Pb-based halide perovskite absorbers. However, up to date, only Ag I -based halide double perovskites have been experimentally synthesized; there are no reports on successful synthesis of Cu I -based analogues. Here we show that, owing to the much higher energy level for the Cu 3d 10 orbitals than for the Ag 4d 10 orbitals, Cu I atoms energetically favor 4-fold coordination, forming [CuX 4 ] tetrahedra (X=halogen), but not 6-fold coordination as required for [CuX 6 ] octahedra. In contrast, Ag I atoms can have both 6- and 4-fold coordinations. Our density functional theory calculations reveal that the synthesis of Cu I halide double perovskites may instead lead to non-perovskites containing [CuX 4 ] tetrahedra, as confirmed by our material synthesis efforts. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Meng, Weiwei; Wang, Xiaoming; Xiao, Zewen; Wang, Jianbo; Mitzi, David B; Yan, Yanfa
2017-07-06
Using density functional theory calculations, we analyze the optical absorption properties of lead (Pb)-free metal halide perovskites (AB 2+ X 3 ) and double perovskites (A 2 B + B 3+ X 6 ) (A = Cs or monovalent organic ion, B 2+ = non-Pb divalent metal, B + = monovalent metal, B 3+ = trivalent metal, X = halogen). We show that if B 2+ is not Sn or Ge, Pb-free metal halide perovskites exhibit poor optical absorptions because of their indirect band gap nature. Among the nine possible types of Pb-free metal halide double perovskites, six have direct band gaps. Of these six types, four show inversion symmetry-induced parity-forbidden or weak transitions between band edges, making them not ideal for thin-film solar cell applications. Only one type of Pb-free double perovskite shows optical absorption and electronic properties suitable for solar cell applications, namely, those with B + = In, Tl and B 3+ = Sb, Bi. Our results provide important insights for designing new metal halide perovskites and double perovskites for optoelectronic applications.
Global expression for representing cohesive-energy curves. II
NASA Technical Reports Server (NTRS)
Schlosser, Herbert; Ferrante, John
1993-01-01
Schlosser et al. (1991) showed that the R dependence of the cohesive energy of partially ionic solids may be characterized by a two-term energy relationship consisting of a Coulomb term arising from the charge transfer, delta-Z, and a scaled universal energy function, E*(a *), which accounts for the partially covalent character of the bond and for repulsion between the atomic cores for small R; a* is a scaled length. In the paper by Schlosser et al., the normalized cohesive-energy curves of NaCl-structure alkali-halide crystals were generated with this expression. In this paper we generate the cohesive-energy curves of several families of partially ionic solids with different crystal structures and differing degrees of ionicity. These include the CsCl-structure Cs halides, and the Tl and Ag halides, which have weaker ionic bonding than the alkali halides, and which have the CsCl and NaCl structures, respectively. The cohesive-energy-curve parameters are then used to generate theoretical isothermal compression curves for the Li, Na, K, Cs, and Ag halides. We find good agreement with the available experimental compression data.
Chang, Wei; Sun, Chunyan; Pang, Xibin; Sheng, Hua; Li, Yue; Ji, Hongwei; Song, Wenjing; Chen, Chuncheng; Ma, Wanhong; Zhao, Jincai
2015-02-09
An efficient redox reaction between organic substrates in solution and photoinduced h(+) vb /e(-) cb on the surface of photocatalysts requires the substrates or solvent to be adsorbed onto the surface, and is consequentially marked by a normal kinetic solvent isotope effect (KSIE ≥ 1). Reported herein is a universal inverse KSIE (0.6-0.8 at 298 K) for the reductive dehalogenation of aromatic halides which cannot adsorb onto TiO2 in a [D0 ]methanol/[D4 ]methanol solution. Combined with in situ ATR-FTIR spectroscopy investigations, a previously unknown pathway for the transformation of these aromatic halides in TiO2 photocatalysis was identified: a proton adduct intermediate, induced by released H(+) /D(+) from solvent oxidation, accompanies a change in hybridization from sp(2) to sp(3) at a carbon atom of the aromatic halides. The protonation event leads these aromatic halides to adsorb onto the TiO2 surface and an ET reaction to form dehalogenated products follows. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Slavney, Adam H.; Leppert, Linn; Bartesaghi, Davide; ...
2017-03-29
In this study, halide double perovskites have recently been developed as less toxic analogs of the lead perovskite solar-cell absorbers APbX 3 (A = monovalent cation; X = Br or I). However, all known halide double perovskites have large bandgaps that afford weak visible-light absorption. The first halide double perovskite evaluated as an absorber, Cs 2AgBiBr 6 (1), has a bandgap of 1.95 eV. Here, we show that dilute alloying decreases 1’s bandgap by ca. 0.5 eV. Importantly, time-resolved photoconductivity measurements reveal long-lived carriers with microsecond lifetimes in the alloyed material, which is very promising for photovoltaic applications. The alloyedmore » perovskite described herein is the first double perovskite to show comparable bandgap energy and carrier lifetime to those of (CH 3NH 3)PbI 3. By describing how energy- and symmetry-matched impurity orbitals, at low concentrations, dramatically alter 1’s band edges, we open a potential pathway for the large and diverse family of halide double perovskites to compete with APbX 3 absorbers.« less
Miscellaneous Lasing Actions in Organo-Lead Halide Perovskite Films.
Duan, Zonghui; Wang, Shuai; Yi, Ningbo; Gu, Zhiyuan; Gao, Yisheng; Song, Qinghai; Xiao, Shumin
2017-06-21
Lasing actions in organo-lead halide perovskite films have been heavily studied in the past few years. However, due to the disordered nature of synthesized perovskite films, the lasing actions are usually understood as random lasers that are formed by multiple scattering. Herein, we demonstrate the miscellaneous lasing actions in organo-lead halide perovskite films. In addition to the random lasers, we show that a single or a few perovskite microparticles can generate laser emissions with their internal resonances instead of multiple scattering among them. We experimentally observed and numerically confirmed whispering gallery (WG)-like microlasers in polygon shaped and other deformed microparticles. Meanwhile, owing to the nature of total internal reflection and the novel shape of the nanoparticle, the size of the perovskite WG laser can be significantly decreased to a few hundred nanometers. Thus, wavelength-scale lead halide perovskite lasers were realized for the first time. All of these laser behaviors are complementary to typical random lasers in perovskite film and will help the understanding of lasing actions in complex lead halide perovskite systems.
Telomere dysfunction and cell survival: Roles for distinct TIN2-containing complexes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Sahn-ho; Davalos, Albert R.; Heo, Seok-Jin
Telomeres are maintained by three DNA binding proteins (TRF1, TRF2 and POT1), and several associated factors. One factor, TIN2, binds TRF1 and TRF2 directly and POT1 indirectly. Along with two other proteins, TPP1 and hRap1, these form a soluble complex that may be the core telomere maintenance complex. It is not clear whether sub-complexes also exist in vivo. We provide evidence for two TIN2 sub-complexes with distinct functions in human cells. We isolated these two TIN2 sub-complexes from nuclear lysates of unperturbed cells and cells expressing TIN2 mutants TIN2-13, TIN2-15C, which cannot bind TRF2 or TRF1, respectively. In cells withmore » wild-type p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere uncapping and eventual growth arrest. In cells lacking p53 function, TIN2-15C was more potent than TIN2-13 in causing telomere dysfunction and cell death. Our findings suggest that distinct TIN2 complexes exist, and that TIN2-15C-sensitive subcomplexes are particularly important for cell survival in the absence of functional p53.« less
Positron Annihilation in Insulating Materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Asoka-Kumar, P; Sterne, PA
2002-10-18
We describe positron results from a wide range of insulating materials. We have completed positron experiments on a range of zeolite-y samples, KDP crystals, alkali halides and laser damaged SiO{sub 2}. Present theoretical understanding of positron behavior in insulators is incomplete and our combined theoretical and experimental approach is aimed at developing a predictive understanding of positrons and positronium annihilation characteristics in insulators. Results from alkali halides and alkaline-earth halides show that positrons annihilate with only the halide ions, with no apparent contribution from the alkali or alkaline-earth cations. This contradicts the results of our existing theory for metals, whichmore » predicts roughly equal annihilation contributions from cation and anion. We also present result obtained using Munich positron microprobe on laser damaged SiO{sub 2} samples.« less
NASA Astrophysics Data System (ADS)
Katan, Claudine; Mohite, Aditya D.; Even, Jacky
2018-05-01
Claudine Katan, Aditya D. Mohite and Jacky Even discuss the possible impact of various entropy contributions (stochastic structural fluctuations, anharmonicity and lattice softness) on the optoelectronic properties of halide perovskite materials and devices.
Strategies to Reduce Tin and Other Metals in Electronic Cigarette Aerosol
Williams, Monique; To, An; Bozhilov, Krassimir; Talbot, Prue
2015-01-01
Background Metals are present in electronic cigarette (EC) fluid and aerosol and may present health risks to users. Objective The objective of this study was to measure the amounts of tin, copper, zinc, silver, nickel and chromium in the aerosol from four brands of EC and to identify the sources of these metals by examining the elemental composition of the atomizer components. Methods Four brands of popular EC were dissected and the cartomizers were examined microscopically. Elemental composition of cartomizer components was determined using integrated energy dispersive X-ray microanalysis, and the concentrations of the tin, copper, zinc silver, nickel, and chromium in the aerosol were determined for each brand using inductively coupled plasma optical emission spectroscopy. Results All filaments were made of nickel and chromium. Thick wires were copper coated with either tin or silver. Wires were joined to each other by tin solder, brazing, or by brass clamps. High concentrations of tin were detected in the aerosol when tin solder joints were friable. Tin coating on copper wires also contributed to tin in the aerosol. Conclusions Tin concentrations in EC aerosols varied both within and between brands. Tin in aerosol was reduced by coating the thick wire with silver rather than tin, placing stable tin solder joints outside the atomizing chamber, joining wires with brass clamps or by brazing rather than soldering wires. These data demonstrate the feasibility of removing tin and other unwanted metals from EC aerosol by altering designs and using materials of suitable quality. PMID:26406602
METHOD OF ALLOYING REACTIVE METALS WITH ALUMINUM OR BERYLLIUM
Runnalls, O.J.C.
1957-10-15
A halide of one or more of the reactive metals, neptunium, cerium and americium, is mixed with aluminum or beryllium. The mass is heated at 700 to 1200 deg C, while maintaining a substantial vacuum of above 10/sup -3/ mm of mercury or better, until the halide of the reactive metal is reduced and the metal itself alloys with the reducing metal. The reaction proceeds efficiently due to the volatilization of the halides of the reducing metal, aluminum or beryllium.
THERMAL DECOMPOSITION OF URANIUM COMPOUNDS
Magel, T.T.; Brewer, L.
1959-02-10
A method is presented of preparing uranium metal of high purity consisting contacting impure U metal with halogen vapor at between 450 and 550 C to form uranium halide vapor, contacting the uranium halide vapor in the presence of H/sub 2/ with a refractory surface at about 1400 C to thermally decompose the uranium halides and deposit molten U on the refractory surface and collecting the molten U dripping from the surface. The entire operation is carried on at a sub-atmospheric pressure of below 1 mm mercury.
Oxidation of hydrogen halides to elemental halogens with catalytic molten salt mixtures
Rohrmann, Charles A.
1978-01-01
A process for oxidizing hydrogen halides by means of a catalytically active molten salt is disclosed. The subject hydrogen halide is contacted with a molten salt containing an oxygen compound of vanadium and alkali metal sulfates and pyrosulfates to produce an effluent gas stream rich in the elemental halogen. The reduced vanadium which remains after this contacting is regenerated to the active higher valence state by contacting the spent molten salt with a stream of oxygen-bearing gas.
Metal halides vapor lasers with inner reactor and small active volume.
NASA Astrophysics Data System (ADS)
Shiyanov, D. V.; Sukhanov, V. B.; Evtushenko, G. S.
2018-04-01
Investigation of the energy characteristics of copper, manganese, lead halide vapor lasers with inner reactor and small active volume 90 cm3 was made. The optimal operating pulse repetition rates, temperatures, and buffer gas pressure for gas discharge tubes with internal and external electrodes are determined. Under identical pump conditions, such systems are not inferior in their characteristics to standard metal halide vapor lasers. It is shown that the use of a zeolite halogen generator provides lifetime laser operation.
Ultrafast time-resolved spectroscopy of lead halide perovskite films
NASA Astrophysics Data System (ADS)
Idowu, Mopelola A.; Yau, Sung H.; Varnavski, Oleg; Goodson, Theodore
2015-09-01
Recently, lead halide perovskites which are organic-inorganic hybrid structures, have been discovered to be highly efficient as light absorbers. Herein, we show the investigation of the excited state dynamics and emission properties of non-stoichiometric precursor formed lead halide perovskites grown by interdiffusion method using steady-state and time-resolved spectroscopic measurements. The influence of the different ratios of the non-stoichiometric precursor solution was examined. The observed photoluminescence properties were correlated with the femtosecond transient absorption measurements.
Unique properties of halide perovskites as possible origins of the superior solar cell performance.
Yin, Wan-Jian; Shi, Tingting; Yan, Yanfa
2014-07-16
Halide perovskites solar cells have the potential to exhibit higher energy conversion efficiencies with ultrathin films than conventional thin-film solar cells based on CdTe, CuInSe2 , and Cu2 ZnSnSe4 . The superior solar-cell performance of halide perovskites may originate from its high optical absorption, comparable electron and hole effective mass, and electrically clean defect properties, including point defects and grain boundaries. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Baesman, S. M.; Miller, L. G.; Oremland, R. S.
2003-12-01
Methyl bromide (MeBr), methyl chloride (MeCl) and methyl iodide (MeI) are reactive trace gases that are produced and released to the atmosphere at the Earths surface. These methyl halides have the potential to influence ozone levels in the stratosphere. Current estimates of the relative contributions of natural and anthropogenic sources of these methyl halides are the subject of considerable debate. In addition, there is uncertainty in the magnitude of some of the largest sinks for these compounds. Hence, the atmospheric budgets of MeBr, MeCl and MeI, while uncertain at present, may be better constrained using stable isotope ratio (13C/12C) mass balances of sources and sinks. Our work has focused on characterizing the effects upon δ 13C values of methyl halides released after reactions which discriminate in favor of 12C during removal processes. Previously, we determined very large fractionations of carbon isotopes by pure cultures of soil bacteria. Further, we have documented large fractionations (kinetic isotope effects or KIEs) of methyl halides in live soils. In the case of MeBr and MeI, substantial fractionation also occurred in heat-killed soil, suggesting that chemical degradation resulted in a shift in the stable isotopic composition. At elevated concentrations, for instance during agricultural soil fumigations, the δ 13C value of MeBr or MeI released from soil can be determined by flux measurements or soil profiles. However, more information is needed regarding the processes responsible for isotope fractionation to be able to extrapolate to areas where the concentration is low or direct measurement is not otherwise possible. We report here on measurements of the fractionation of carbon isotopes in methyl halides during degradation by chemical processes that are likely to occur in soil or seawater. These processes include aqueous hydrolysis and halide exchange and the methylation of organic matter using humic acid as the model methyl acceptor. Results are compared with fractionation achieved during the uptake of methyl halides by live and heat-killed soils.
METHOD FOR JOINING ALUMINUM TO STAINLESS STEEL
Lemon, L.C.
1960-05-24
Aluminum may be joined to stainless steel without the use of flux by tinning the aluminum with a tin solder containing 1% silver and 1% lead, tinning the stainless steel with a 50% lead 50% tin solder, and then sweating the tinned surfaces together.
2015-09-01
ARL-TR-7448 ● SEP 2015 US Army Research Laboratory Raman Scattering from Tin by Patrick A Folkes, Patrick Taylor, Charles Rong...REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Raman Scattering from Tin 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c... tin as an analytical tool for discerning specific allotropic differences in ultra-thin tin films, and discerning differences between the tin and the
Electrochemical mechanism of tin membrane electrodeposition under ultrasonic waves.
Nan, Tianxiang; Yang, Jianguang; Chen, Bing
2018-04-01
Tin was electrodeposited from chloride solutions using a membrane cell under ultrasonic waves. Cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CHR), and chronopotentiometry were applied to investigate the electrochemical mechanism of tin electrodeposition under ultrasonic field. Chronoamperometry curves showed that the initial process of tin electrodeposition followed the diffusion controlled three-dimensional nucleation and grain growth mechanism. The analysis of the cyclic voltammetry and linear sweep voltammetry diagrams showed that the application of ultrasound can change the tin membrane electro-deposition reaction from diffusion to electrochemical control, and the optimum parameters for tin electrodeposition were H + concentration 3.5 mol·L -1 , temperature 35 °C and ultrasonic power 100 W. The coupling ultrasonic field played a role in refining the grain in this process. The growth of tin crystals showed no orientation preferential, and the tin deposition showed a tendency to form a regular network structure after ultrasonic coupling. While in the absence of ultrasonic coupling, the growth of tin crystals has a high preferential orientation, and the tin deposition showed a tendency to form tin whiskers. Ultrasonic coupling was more favorable for obtaining a more compact and smoother cathode tin layer. Copyright © 2017 Elsevier B.V. All rights reserved.
Electrochemical Doping of Halide Perovskites with Ion Intercalation.
Jiang, Qinglong; Chen, Mingming; Li, Junqiang; Wang, Mingchao; Zeng, Xiaoqiao; Besara, Tiglet; Lu, Jun; Xin, Yan; Shan, Xin; Pan, Bicai; Wang, Changchun; Lin, Shangchao; Siegrist, Theo; Xiao, Qiangfeng; Yu, Zhibin
2017-01-24
Halide perovskites have recently been investigated for various solution-processed optoelectronic devices. The majority of studies have focused on using intrinsic halide perovskites, and the intentional incoporation of dopants has not been well explored. In this work, we discovered that small alkali ions, including lithium and sodium ions, could be electrochemically intercalated into a variety of halide and pseudohalide perovskites. The ion intercalation caused a lattice expansion of the perovskite crystals and resulted in an n-type doping of the perovskites. Such electrochemical doping improved the conductivity and changed the color of the perovskites, leading to an electrochromism with more than 40% reduction of transmittance in the 450-850 nm wavelength range. The doped perovskites exhibited improved electron injection efficiency into the pristine perovskite crystals, resulting in bright light-emitting diodes with a low turn-on voltage.
Halogen radicals contribute to photooxidation in coastal and estuarine waters
Parker, Kimberly M.; Mitch, William A.
2016-01-01
Although halogen radicals are recognized to form as products of hydroxyl radical (•OH) scavenging by halides, their contribution to the phototransformation of marine organic compounds has received little attention. We demonstrate that, relative to freshwater conditions, seawater halides can increase photodegradation rates of domoic acid, a marine algal toxin, and dimethyl sulfide, a volatile precursor to cloud condensation nuclei, up to fivefold. Using synthetic seawater solutions, we show that the increased photodegradation is specific to dissolved organic matter (DOM) and halides, rather than other seawater salt constituents (e.g., carbonates) or photoactive species (e.g., iron and nitrate). Experiments in synthetic and natural coastal and estuarine water samples demonstrate that the halide-specific increase in photodegradation could be attributed to photochemically generated halogen radicals rather than other photoproduced reactive intermediates [e.g., excited-state triplet DOM (3DOM*), reactive oxygen species]. Computational kinetic modeling indicates that seawater halogen radical concentrations are two to three orders of magnitude greater than freshwater •OH concentrations and sufficient to account for the observed halide-specific increase in photodegradation. Dark •OH generation by gamma radiolysis demonstrates that halogen radical production via •OH scavenging by halides is insufficient to explain the observed effect. Using sensitizer models for DOM chromophores, we show that halogen radicals are formed predominantly by direct oxidation of Cl− and Br− by 3DOM*, an •OH-independent pathway. Our results indicate that halogen radicals significantly contribute to the phototransformation of algal products in coastal or estuarine surface waters. PMID:27162335
NASA Technical Reports Server (NTRS)
Paula, S.; Volkov, A. G.; Deamer, D. W.
1998-01-01
Two alternative mechanisms are frequently used to describe ionic permeation of lipid bilayers. In the first, ions partition into the hydrophobic phase and then diffuse across (the solubility-diffusion mechanism). The second mechanism assumes that ions traverse the bilayer through transient hydrophilic defects caused by thermal fluctuations (the pore mechanism). The theoretical predictions made by both models were tested for halide anions by measuring the permeability coefficients for chloride, bromide, and iodide as a function of bilayer thickness, ionic radius, and sign of charge. To vary the bilayer thickness systematically, liposomes were prepared from monounsaturated phosphatidylcholines (PC) with chain lengths between 16 and 24 carbon atoms. The fluorescent dye MQAE (N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide) served as an indicator for halide concentration inside the liposomes and was used to follow the kinetics of halide flux across the bilayer membranes. The observed permeability coefficients ranged from 10(-9) to 10(-7) cm/s and increased as the bilayer thickness was reduced. Bromide was found to permeate approximately six times faster than chloride through bilayers of identical thickness, and iodide permeated three to four times faster than bromide. The dependence of the halide permeability coefficients on bilayer thickness and on ionic size were consistent with permeation of hydrated ions by a solubility-diffusion mechanism rather than through transient pores. Halide permeation therefore differs from that of a monovalent cation such as potassium, which has been accounted for by a combination of the two mechanisms depending on bilayer thickness.
FRACTIONAL DISTILLATION SEPARATION OF PLUTONIUM VALUES FROM LIGHT ELEMENT VALUES
Cunningham, B.B.
1957-12-17
A process is described for removing light element impurities from plutonium. It has been found that plutonium contaminated with impurities may be purified by converting the plutonium to a halide and purifying the halide by a fractional distillation whereby impurities may be distilled from the plutonium halide. A particularly effective method includes the step of forming a lower halide such as the trior tetrahalide and distilling the halide under conditions such that no decomposition of the halide occurs. Molecular distillation methods are particularly suitable for this process. The apparatus may comprise an evaporation plate with means for heating it and a condenser surface with means for cooling it. The condenser surface is placed at a distance from the evaporating surface less than the mean free path of molecular travel of the material being distilled at the pressure and temperature used. The entire evaporating system is evacuated until the pressure is about 10/sup -4/ millimeters of mercury. A high temperuture method is presented for sealing porous materials such as carbon or graphite that may be used as a support or a moderator in a nuclear reactor. The carbon body is subjected to two surface heats simultaneously in an inert atmosphere; the surface to be sealed is heated to 1500 degrees centigrade; and another surface is heated to 300 degrees centigrade, whereupon the carbon vaporizes and flows to the cooler surface where it is deposited to seal that surface. This method may be used to seal a nuclear fuel in the carbon structure.
NASA Astrophysics Data System (ADS)
Guo, Yaguang; Saidi, Wissam A.; Wang, Qian
2017-09-01
Halide perovskites and van der Waals (vdW) heterostructures are both of current interest owing to their novel properties and potential applications in nano-devices. Here, we show the great potential of 2D halide perovskite sheets (C4H9NH3)2PbX4 (X = Cl, Br and I) that were synthesized recently (Dou et al 2015 Science 349 1518-21) as the channel materials contacting with graphene and other 2D metallic sheets to form van der Waals heterostructures for field effect transistor (FET). Based on state-of-the-art theoretical simulations, we show that the intrinsic properties of the 2D halide perovskites are preserved in the heterojunction, which is different from the conventional contact with metal surfaces. The 2D halide perovskites form a p-type Schottky barrier (Φh) contact with graphene, where tunneling barrier exists, and a negative band bending occurs at the lateral interface. We demonstrate that the Schottky barrier can be turned from p-type to n-type by doping graphene with nitrogen atoms, and a low-Φh or an Ohmic contact can be realized by doping graphene with boron atoms or replacing graphene with other high-work-function 2D metallic sheets such as ZT-MoS2, ZT-MoSe2 and H-NbS2. This study not only predicts a 2D halide perovskite-based FETs, but also enhances the understanding of tuning Schottky barrier height in device applications.
42 CFR 425.306 - Participation agreement and exclusivity of ACO participant TINs.
Code of Federal Regulations, 2014 CFR
2014-10-01
... participant TINs. 425.306 Section 425.306 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT... participant TINs. (a) For purposes of the Shared Savings Program, each ACO participant TIN is required to commit to a participation agreement with CMS. (b) Each ACO participant TIN upon which beneficiary...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-13
...-Services Registration TIN Matching--Application and Screens for TIN Matching Interactive AGENCY: Internal...(c)(2)(A)). Currently, the IRS is soliciting comments concerning e- Services registration TIN matching--application and screens for TIN matching interactive. DATES: Written comments should be received...
42 CFR 425.306 - Participation agreement and exclusivity of ACO participant TINs.
Code of Federal Regulations, 2013 CFR
2013-10-01
... participant TINs. 425.306 Section 425.306 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT... participant TINs. (a) For purposes of the Shared Savings Program, each ACO participant TIN is required to commit to a participation agreement with CMS. (b) Each ACO participant TIN upon which beneficiary...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-04
...-Services Registration TIN Matching--Application and Screens for TIN Matching Interactive AGENCY: Internal...(c)(2)(A)). Currently, the IRS is soliciting comments concerning e- Services Registration TIN Matching--Application and Screens for TIN Matching Interactive. DATES: Written comments should be received...
42 CFR 425.306 - Participation agreement and exclusivity of ACO participant TINs.
Code of Federal Regulations, 2012 CFR
2012-10-01
... participant TINs. 425.306 Section 425.306 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT... participant TINs. (a) For purposes of the Shared Savings Program, each ACO participant TIN is required to commit to a participation agreement with CMS. (b) Each ACO participant TIN upon which beneficiary...
Ratchford, Michael E.
2002-01-01
Boulder Basin is in a northwest-trending belt of allochthonous Paleozoic rocks in the Boulder Mountains of central Idaho. Regional Tertiary extension resulted in widespread normal faulting and coeval emplacement of shallow-level intrusions and extrusive rocks of the Challis Volcanic Group. Epigenetic lead-zinc-silver-antimony-tin-gold vein deposits formed during Tertiary extension and are hosted within Paleozoic strata. The major orebodies are in the lower plate of the Boulder Basin thrust fault, in massive quartzite of the Middle Pennsylvanian to Lower Permian Wood River Formation. Anomalous concentrations of tin are present in the base-metal mineral assemblage of the Boulder Basin ore deposits. The tin-bearing veins in Boulder Basin are strikingly similar to Bolivian tin deposits. The deposit model for Bolivian tin deposits identifies buried tin porphyry below the tin-bearing vein system.
Phonon Speed, Not Scattering, Differentiates Thermal Transport in Lead Halide Perovskites.
Elbaz, Giselle A; Ong, Wee-Liat; Doud, Evan A; Kim, Philip; Paley, Daniel W; Roy, Xavier; Malen, Jonathan A
2017-09-13
Thermal management plays a critical role in the design of solid state materials for energy conversion. Lead halide perovskites have emerged as promising candidates for photovoltaic, thermoelectric, and optoelectronic applications, but their thermal properties are still poorly understood. Here, we report on the thermal conductivity, elastic modulus, and sound speed of a series of lead halide perovskites MAPbX 3 (X = Cl, Br, I), CsPbBr 3 , and FAPbBr 3 (MA = methylammonium, FA = formamidinium). Using frequency domain thermoreflectance, we find that the room temperature thermal conductivities of single crystal lead halide perovskites range from 0.34 to 0.73 W/m·K and scale with sound speed. These results indicate that regardless of composition, thermal transport arises from acoustic phonons having similar mean free path distributions. A modified Callaway model with Born von Karmen-based acoustic phonon dispersion predicts that at least ∼70% of thermal conductivity results from phonons having mean free paths shorter than 100 nm, regardless of whether resonant scattering is invoked. Hence, nanostructures or crystal grains with dimensions smaller than 100 nm will appreciably reduce thermal transport. These results are important design considerations to optimize future lead halide perovskite-based photovoltaic, optoelectronic, and thermoelectric devices.
Advancement on Lead-Free Organic-Inorganic Halide Perovskite Solar Cells: A Review.
Sani, Faruk; Shafie, Suhaidi; Lim, Hong Ngee; Musa, Abubakar Ohinoyi
2018-06-14
Remarkable attention has been committed to the recently discovered cost effective and solution processable lead-free organic-inorganic halide perovskite solar cells. Recent studies have reported that, within five years, the reported efficiency has reached 9.0%, which makes them an extremely promising and fast developing candidate to compete with conventional lead-based perovskite solar cells. The major challenge associated with the conventional perovskite solar cells is the toxic nature of lead (Pb) used in the active layer of perovskite material. If lead continues to be used in fabricating solar cells, negative health impacts will result in the environment due to the toxicity of lead. Alternatively, lead free perovskite solar cells could give a safe way by substituting low-cost, abundant and non toxic material. This review focuses on formability of lead-free organic-inorganic halide perovskite, alternative metal cations candidates to replace lead (Pb), and possible substitutions of organic cations, as well as halide anions in the lead-free organic-inorganic halide perovskite architecture. Furthermore, the review gives highlights on the impact of organic cations, metal cations and inorganic anions on stability and the overall performance of lead free perovskite solar cells.
Octahedral tilting instabilities in inorganic halide perovskites
NASA Astrophysics Data System (ADS)
Bechtel, Jonathon S.; Van der Ven, Anton
2018-02-01
Dynamic instabilities, stabilized by anharmonic interactions in cubic and tetragonal halide perovskites at high temperature, play a role in the electronic structure and optoelectronic properties of halide perovskites. In particular, inorganic and hybrid perovskite materials undergo structural phase transitions associated with octahedral tilts of the metal-halide octahedra. We investigate the structural instabilities present in inorganic Cs M X3 perovskites with Pb or Sn on the metal site and Br or I on the X site. Defining primary order parameters in terms of symmetry-adapted collective displacement modes and secondary order parameters in terms of symmetrized Hencky strain components, we unravel the coupling between octahedral tilt modes and macroscopic strains as well as the role of A -site displacements in perovskite phase stability. Symmetry-allowed secondary strain order parameters are enumerated for the 14 unique perovskite tilt systems. Using first-principles calculations to explore the Born-Oppenheimer energy surface in terms of symmetrized order parameters, we find coupling between octahedral tilting and A -site displacements is necessary to stabilize P n m a ground states. Additionally, we show that the relative stability of an inorganic halide perovskite tilt system correlates with the volume decrease from the high-symmetry cubic phase to the low-symmetry distorted phase.
NASA Astrophysics Data System (ADS)
Nepal, Niraj K.; Ruzsinszky, Adrienn; Bates, Jefferson E.
2018-03-01
The ground state structural and energetic properties for rocksalt and cesium chloride phases of the cesium halides were explored using the random phase approximation (RPA) and beyond-RPA methods to benchmark the nonempirical SCAN meta-GGA and its empirical dispersion corrections. The importance of nonadditivity and higher-order multipole moments of dispersion in these systems is discussed. RPA generally predicts the equilibrium volume for these halides within 2.4% of the experimental value, while beyond-RPA methods utilizing the renormalized adiabatic LDA (rALDA) exchange-correlation kernel are typically within 1.8%. The zero-point vibrational energy is small and shows that the stability of these halides is purely due to electronic correlation effects. The rAPBE kernel as a correction to RPA overestimates the equilibrium volume and could not predict the correct phase ordering in the case of cesium chloride, while the rALDA kernel consistently predicted results in agreement with the experiment for all of the halides. However, due to its reasonable accuracy with lower computational cost, SCAN+rVV10 proved to be a good alternative to the RPA-like methods for describing the properties of these ionic solids.
Shape Evolution and Single Particle Luminescence of Organometal Halide Perovskite Nanocrystals
Zhu, Feng; Men, Long; Guo, Yijun; ...
2015-02-09
Organometallic halide perovskites CH 3NH 3PbX 3 (X = I, Br, Cl) have quickly become one of the most promising semiconductors for solar cells, with photovoltaics made of these materials reaching power conversion efficiencies of near 20%. Improving our ability to harness the full potential of organometal halide perovskites will require more controllable syntheses that permit a detailed understanding of their fundamental chemistry and photophysics. In our manuscript, we systematically synthesize CH 3NH 3PbX 3 (X = I, Br) nanocrystals with different morphologies (dots, rods, plates or sheets) by using different solvents and capping ligands. CH 3NH 3PbX 3 nanowiresmore » and nanorods capped with octylammonium halides show relatively higher photoluminescence (PL) quantum yields and long PL lifetimes. CH 3NH 3PbI 3 nanowires monitored at the single particle level show shape-correlated PL emission across whole particles, with little photobleaching observed and very few off periods. Our work highlights the potential of low-dimensional organometal halide perovskite semiconductors in constructing new porous and nanostructured solar cell architectures, as well as in applying these materials to other fields such as light-emitting devices and single particle imaging and tracking.« less
Determination of the structural phase and octahedral rotation angle in halide perovskites
NASA Astrophysics Data System (ADS)
dos Reis, Roberto; Yang, Hao; Ophus, Colin; Ercius, Peter; Bizarri, Gregory; Perrodin, Didier; Shalapska, Tetiana; Bourret, Edith; Ciston, Jim; Dahmen, Ulrich
2018-02-01
A key to the unique combination of electronic and optical properties in halide perovskite materials lies in their rich structural complexity. However, their radiation sensitive nature limits nanoscale structural characterization requiring dose efficient microscopic techniques in order to determine their structures precisely. In this work, we determine the space-group and directly image the Br halide sites of CsPbBr3, a promising material for optoelectronic applications. Based on the symmetry of high-order Laue zone reflections of convergent-beam electron diffraction, we identify the tetragonal (I4/mcm) structural phase of CsPbBr3 at cryogenic temperature. Electron ptychography provides a highly sensitive phase contrast measurement of the halide positions under low electron-dose conditions, enabling imaging of the elongated Br sites originating from the out-of-phase octahedral rotation viewed along the [001] direction of I4/mcm persisting at room temperature. The measurement of these features and comparison with simulations yield an octahedral rotation angle of 6.5°(±1.5°). The approach demonstrated here opens up opportunities for understanding the atomic scale structural phenomena applying advanced characterization tools on a wide range of radiation sensitive halide-based all-inorganic and hybrid organic-inorganic perovskites.
Ichikawa, Makoto; Ide, Nagatoshi; Shiraishi, Sumihiro; Ono, Kazuhisa
2005-06-01
Combination of cyanocobalamin (VB12) and ascorbic acid (VC) has been widely seen in pharmaceutical products and dietary supplements. However, VB12 has been reported that its behavior in stability in aqueous solution is quite different when VC is mixed. In the present study, we examined the stabilities of these vitamins in acetate buffer (pH 4.8) using high performance liquid chromatography. Degradation of VB12 was not observed in the absence of VC in the buffer. However, when VC was mixed in the VB12 solution, VB12 concentrations decreased in accordance with VC degradation. VB12 and VC degradations were inhibited by adding sodium halides to acetate buffer at pH 4.8. These stabilization effects were also observed in the range from pH 3.5 to 5.3 and by adding potassium, magnesium, and calcium halides. Furthermore, our data demonstrated that increases in the halide anion concentrations and atomic number (Cl-
Unraveling the Role of Monovalent Halides in Mixed-Halide Organic-Inorganic Perovskites.
Deepa, Melepurath; Ramos, F Javier; Shivaprasad, S M; Ahmad, Shahzada
2016-03-16
The performance of perovskite solar cells is strongly influenced by the composition and microstructure of the perovskite. A recent approach to improve the power conversion efficiencies utilized mixed-halide perovskites, but the halide ions and their roles were not directly studied. Unraveling their precise location in the perovskite layer is of paramount importance. Here, we investigated four different perovskites by using X-ray photoelectron spectroscopy, and found that among the three studied mixed-halide perovskites, CH3 NH3 Pb(I0.74 Br0.26 )3 and CH3 NH3 PbBr3-x Clx show peaks that unambiguously demonstrate the presence of iodide and bromide in the former, and bromide and chloride in the latter. The CH3 NH3 PbI3-x Clx perovskite shows anomalous behavior, the iodide content far outweighs that of the chloride; a small proportion of chloride, in all likelihood, resides deep within the TiO2 /absorber layer. Our study reveals that there are many distinguishable structural differences between these perovskites, and that these directly impact the photovoltaic performances. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Clues from defect photochemistry
NASA Astrophysics Data System (ADS)
De Angelis, Filippo; Petrozza, Annamaria
2018-05-01
Charge carriers in metal halide perovskites seem to be only marginally affected by defect-related trap states. Filippo De Angelis and Annamaria Petrozza suggest that the key to this behaviour lies in the redox chemistry of halide defects.
10 CFR 431.321 - Purpose and scope.
Code of Federal Regulations, 2012 CFR
2012-01-01
... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures § 431.321 Purpose and scope. This subpart contains energy conservation requirements for metal halide lamp ballasts and fixtures, pursuant to Part A of Title III of the...
10 CFR 431.321 - Purpose and scope.
Code of Federal Regulations, 2010 CFR
2010-01-01
... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures § 431.321 Purpose and scope. This subpart contains energy conservation requirements for metal halide lamp ballasts and fixtures, pursuant to Part A-1 of Title III of the...
10 CFR 431.321 - Purpose and scope.
Code of Federal Regulations, 2014 CFR
2014-01-01
... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures § 431.321 Purpose and scope. This subpart contains energy conservation requirements for metal halide lamp ballasts and fixtures, pursuant to Part A of Title III of the...
10 CFR 431.321 - Purpose and scope.
Code of Federal Regulations, 2013 CFR
2013-01-01
... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures § 431.321 Purpose and scope. This subpart contains energy conservation requirements for metal halide lamp ballasts and fixtures, pursuant to Part A of Title III of the...
10 CFR 431.321 - Purpose and scope.
Code of Federal Regulations, 2011 CFR
2011-01-01
... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures § 431.321 Purpose and scope. This subpart contains energy conservation requirements for metal halide lamp ballasts and fixtures, pursuant to Part A of Title III of the...
Thermodynamic reactivity, growth and characterization of mercurous halide crystals
NASA Technical Reports Server (NTRS)
Singh, N. B.; Gottlieb, M.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.; Singh, M.; Glicksman, M. E.; Paradies, C.
1992-01-01
Thermodynamic calculations were carried out for the Hg-X-O system (X = Cl, Br, I) to identify the potential sources of contamination and relative stability of oxides and oxy-halide phases. The effect of excess mercury vapor pressure on the optical quality of mercurous halide crystal was studied by growing several mercurous chloride crystals from mercury-rich composition. The optical quality of crystals was examined by birefringence interferometry and laser scattering studies. Crystals grown in slightly mercury-rich composition showed improved optical quality relative to stoichiometric crystals.
Environmental Effects on the Photophysics of Organic-Inorganic Halide Perovskites.
Galisteo-López, Juan F; Anaya, M; Calvo, M E; Míguez, H
2015-06-18
The photophysical properties of films of organic-inorganic lead halide perovskites under different ambient conditions are herein reported. We demonstrate that their luminescent properties are determined by the interplay between photoinduced activation and darkening processes, which strongly depend on the atmosphere surrounding the samples. We have isolated oxygen and moisture as the key elements in each process, activation and darkening, both of which involve the interaction with photogenerated carriers. These findings show that environmental factors play a key role in the performance of lead halide perovskites as efficient luminescent materials.
Environmental Effects on the Photophysics of Organic–Inorganic Halide Perovskites
2015-01-01
The photophysical properties of films of organic–inorganic lead halide perovskites under different ambient conditions are herein reported. We demonstrate that their luminescent properties are determined by the interplay between photoinduced activation and darkening processes, which strongly depend on the atmosphere surrounding the samples. We have isolated oxygen and moisture as the key elements in each process, activation and darkening, both of which involve the interaction with photogenerated carriers. These findings show that environmental factors play a key role in the performance of lead halide perovskites as efficient luminescent materials. PMID:26266592
Thallous halide materials for use in cryogenic applications
NASA Technical Reports Server (NTRS)
Lawless, William N. (Inventor)
1981-01-01
Thallous halides, either alone or in combination with other ceramic materials, are used in cryogenic applications such as heat exchange material for the regenerator section of a closed-cycle cryogenic refrigeration section, as stabilizing coatings for superconducting wires, and as dielectric insulating materials. The thallous halides possess unusually large specific heats at low temperatures, have large thermal conductivities, are nonmagnetic, and are nonconductors of electricity. They can be formed into a variety of shapes such as spheres, bars, rods, or the like and can be coated onto substrates.
26 CFR 1.6050S-0 - Table of contents.
Code of Federal Regulations, 2011 CFR
2011-04-01
... penalties for failures to include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN. (4) Failure to furnish TIN. (f) Effective date. § 1.6050S-2TElectronic... include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN...
26 CFR 1.6050S-0 - Table of contents.
Code of Federal Regulations, 2014 CFR
2014-04-01
... penalties for failures to include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN. (4) Failure to furnish TIN. (f) Effective date. § 1.6050S-2TElectronic... include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN...
26 CFR 1.6050S-0 - Table of contents.
Code of Federal Regulations, 2013 CFR
2013-04-01
... penalties for failures to include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN. (4) Failure to furnish TIN. (f) Effective date. § 1.6050S-2TElectronic... include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN...
78 FR 39644 - Information Reporting for Affordable Insurance Exchanges
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-02
... Exchange-- (i) The name, address, and taxpayer identification number (TIN), or date of birth if a TIN is... advance credit payments (taxpayer), and the name and TIN of the individual's spouse, if applicable; (ii) The name, address, and TIN, or date of birth if a TIN is not available, of an adult enrolling in...
26 CFR 1.6050S-0 - Table of contents.
Code of Federal Regulations, 2010 CFR
2010-04-01
... penalties for failures to include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN. (4) Failure to furnish TIN. (f) Effective date. § 1.6050S-2TElectronic... include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN...
26 CFR 1.6050S-0 - Table of contents.
Code of Federal Regulations, 2012 CFR
2012-04-01
... penalties for failures to include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN. (4) Failure to furnish TIN. (f) Effective date. § 1.6050S-2TElectronic... include a correct TIN. (i) In general. (ii) Acting in a responsible manner. (iii) Manner of soliciting TIN...
Nanostructure of propylammonium nitrate in the presence of poly(ethylene oxide) and halide salts
NASA Astrophysics Data System (ADS)
Stefanovic, Ryan; Webber, Grant B.; Page, Alister J.
2018-05-01
Nanoscale structure of protic ionic liquids is critical to their utility as molecular electrochemical solvents since it determines the capacity to dissolve salts and polymers such as poly(ethylene oxide) (PEO). Here we use quantum chemical molecular dynamics simulations to investigate the impact of dissolved halide anions on the nanostructure of an archetypal nanostructured protic ionic liquid, propylammonium nitrate (PAN), and how this impacts the solvation of a model PEO polymer. At the molecular level, PAN is nanostructured, consisting of charged/polar and uncharged/nonpolar domains. The charged domain consists of the cation/anion charge groups, and is formed by their electrostatic interaction. This domain solvophobically excludes the propyl chains on the cation, which form a distinct, self-assembled nonpolar domain within the liquid. Our simulations demonstrate that the addition of Cl- and Br- anions to PAN disrupts the structure within the PAN charged domain due to competition between nitrate and halide anions for the ammonium charge centre. This disruption increases with halide concentration (up to 10 mol. %). However, at these concentrations, halide addition has little effect on the structure of the PAN nonpolar domain. Addition of PEO to pure PAN also disrupts the structure within the charged domain of the liquid due to hydrogen bonding between the charge groups and the terminal PEO hydroxyl groups. There is little other association between the PEO structure and the surrounding ionic liquid solvent, with strong PEO self-interaction yielding a compact, coiled polymer morphology. Halide addition results in greater association between the ionic liquid charge centres and the ethylene oxide components of the PEO structure, resulting in reduced conformational flexibility, compared to that observed in pure PAN. Similarly, PEO self-interactions increase in the presence of Cl- and Br- anions, compared to PAN, indicating that the addition of halide salts to PAN decreases its utility as a molecular solvent for polymers such as PEO.
The prognostic value of tumor-infiltrating neutrophils in gastric adenocarcinoma after resection.
Zhao, Jing-jing; Pan, Ke; Wang, Wei; Chen, Ju-gao; Wu, Yan-heng; Lv, Lin; Li, Jian-jun; Chen, Yi-bing; Wang, Dan-dan; Pan, Qiu-zhong; Li, Xiao-dong; Xia, Jian-chuan
2012-01-01
Several pieces of evidence indicate that tumor-infiltrating neutrophils (TINs) are correlated to tumor progression. In the current study, we explore the relationship between TINs and clinicopathological features of gastric adenocarcinoma patients. Furthermore, we investigated the prognostic value of TINs. The study was comprised of two groups, training group (115 patients) and test group (97 patients). Biomarkers (intratumoral CD15+ neutrophils) were assessed by immunohistochemistry. The relationship between clinicopathological features and patient outcome were evaluated using Cox regression and Kaplan-Meier analysis. Immunohistochemical detection showed that the tumor-infiltrating neutrophils (TINs) in the training group ranged from 0.00-115.70 cells/high-power microscopic field (HPF) and the median number was 21.60 cells/HPF. Based on the median number, the patients were divided into high and low TINs groups. Chi-square test analysis revealed that the density of CD15+ TINs was positively associated with lymph node metastasis (p = 0.024), distance metastasis (p = 0.004) and UICC (International Union Against Cancer) staging (p = 0.028). Kaplan-Meier analysis showed that patients with a lower density of TINs had a better prognosis than patients with a higher density of TINs (p = 0.002). Multivariate Cox's analysis showed that the density of CD15+ TINs was an independent prognostic factor for overall survival of gastric adenocarcinoma patients. Using another 97 patients as a test group and basing on the median number of TINs (21.60 cells/HPF) coming from the training group, Kaplan-Meier analysis also showed that patients with a lower density of TINs had a better prognosis than patients with a higher density of TINs (p = 0.032). The results verify that the number of CD15+ TINs can predict the survival of gastric adenocarcinoma surgical patients. The presence of CD15+ TINs is an independent and unfavorable factor in the prognosis of gastric adenocarcinoma patients. Targeting CD15+ TINs may be a potential intervenient therapy in the future.
NASA Astrophysics Data System (ADS)
Rustandi, Andi; Wafa' Nawawi, Fuad; Pratesa, Yudha; Cahyadi, Agung
2018-01-01
Tin slag, a by-product of tin production has been used in cementitious application. The present investigation focuses on the suitability of tin slag as primary component in cement and as component that substitute some amount of Portland Cement. The tin slags studied were taken from Bangka, Indonesia. The main contents of the tin slag are SiO2, Al2O3, and Fe2O3 according to the XRF investigation. The aim of this article was to study the mechanical behaviour (compressive strength), microstructure and leaching behaviour of tin slag blended cement. This study used air-cooled tin slag that had been passed through 400# sieve to replace Portland Cement with ratio 0, 10, 20, 30, 40 by weight. Cement pastes and tin slag blended cement pastes were prepared by using water/cement ratio (W/C) of 0.40 by weight and hydrated for various curing ages of 3, 7, 14 days The microstructure of the raw tin slag was investigated using Scanning Electron Microscope (SEM). The phase composition of each cement paste was investigated using X-ray Diffraction (XRD). The aim of the leachability test was to investigate the environmental impacts of tin slag blended cement product in the range 4-8 pH by using static pH-dependent leaching test. The result show that the increase of the tin slag content decreasing the mortar compressive strength at early ages. The use of tin slag in cement provide economic benefits for all related industries.
Silver-halide photographic materials based on nanoporous glasses
NASA Astrophysics Data System (ADS)
Andreeva, O. V.; Obyknovennaya, I. E.; Gavrilyuk, E. R.; Paramonov, A. A.; Kushnarenko, A. P.
2005-12-01
This paper discusses the results of an investigation of the recording of composite nanoporous photographic materials with a photosensitive composite made from silver halide in gelatin, developed and created at S. I. Vavilov State Optical Institute.
SHSG processing for three-wavelength HOEs recording in silver halide materials
NASA Astrophysics Data System (ADS)
Kim, Jong Man; Choi, Yoon S.; Bjelkhagen, Hans I.; Phillips, Nicholas J.
2002-06-01
The recording and processing technique for color HOEs in ultrafine-grain panchromatic silver halide emulsions is presented. It is possible to obtain high diffraction efficiency employing the silver halide sensitized gelatin (SHSG) process. SHSG holograms are similar to holograms recorded in dichromated gelatin (DCG). The drawback of DCG is its low sensitivity and limited spectral response. Panchromatic silver halide materials from Slavich can be processed in such a way that the final holograms have properties like a DCG hologram. The processing method or microvoid technique has been optimized for three laser- wavelength recordings in Slavich PFG-03C emulsion. For example, applying this new processing technique high- efficiency white holographic reflectors can be manufactured. The technique is also suitable for producing efficiency color display holograms. In particular, masters for mass production of color holograms or color HOEs can be performed by contact-copying into photopolymer materials because the reconstruction wavelengths are identical to the recording wavelengths.
Local polar fluctuations in lead halide perovskite crystals
Yaffe, Omer; Guo, Yinsheng; Tan, Liang Z.; ...
2017-03-28
Hybrid lead-halide perovskites have emerged as an excellent class of photovoltaic materials. Recent reports suggest that the organic molecular cation is responsible for local polar fluctuations that inhibit carrier recombination. We combine low-frequency Raman scattering with first-principles molecular dynamics (MD) to study the fundamental nature of these local polar fluctuations. Our observations of a strong central peak in the cubic phase of both hybrid (CH 3NH 3PbBr 3) and all-inorganic (CsPbBr 3) lead-halide perovskites show that anharmonic, local polar fluctuations are intrinsic to the general lead-halide perovskite structure, and not unique to the dipolar organic cation. Furthermore, MD simulations indicatemore » that head-to-head Cs motion coupled to Br face expansion, occurring on a few hundred femtosecond time scale, drives the local polar fluctuations in CsPbBr 3.« less
Method for removing acid gases from a gaseous stream
Gorin, Everett; Zielke, Clyde W.
1981-01-01
In a process for hydrocracking a heavy aromatic polynuclear carbonaceous feedstock containing reactive alkaline constituents to produce liquid hydrocarbon fuels boiling below about 475.degree. C. at atmospheric pressure by contacting the feedstock with hydrogen in the presence of a molten metal halide catalyst, thereafter separating a gaseous stream containing hydrogen, at least a portion of the hydrocarbon fuels and acid gases from the molten metal halide and regenerating the molten metal halide, thereby producing a purified molten metal halide stream for recycle to the hydrocracking zone, an improvement comprising; contacting the gaseous acid gas, hydrogen and hydrocarbon fuels-containing stream with the feedstock containing reactive alkaline constituents to remove acid gases from the acid gas containing stream. Optionally at least a portion of the hydrocarbon fuels are separated from gaseous stream containing hydrogen, hydrocarbon fuels and acid gases prior to contacting the gaseous stream with the feedstock.
Jing, Qiang; Zhang, Mian; Huang, Xiang; Ren, Xiaoming; Wang, Peng; Lu, Zhenda
2017-06-08
In recent years, there has been an unprecedented rise in the research of halide perovskites because of their important optoelectronic applications, including photovoltaic cells, light-emitting diodes, photodetectors and lasers. The most pressing question concerns the stability of these materials. Here faster degradation and PL quenching are observed at higher iodine content for mixed-halide perovskite CsPb(Br x I 1-x ) 3 nanocrystals, and a simple yet effective method is reported to significantly enhance their stability. After selective etching with acetone, surface iodine is partially etched away to form a bromine-rich surface passivation layer on mixed-halide perovskite nanocrystals. This passivation layer remarkably stabilizes the nanocrystals, making their PL intensity improved by almost three orders of magnitude. It is expected that a similar passivation layer can also be applied to various other kinds of perovskite materials with poor stability issues.
2015-11-18
thickness of the film, or substrate. In this work, we report calculations for titanium nitride ( TiN ), a promising material for plasmonic applications...stoichiometric bulk TiN , as well as of the TiN (100), TiN (110), and TiN (111) outermost surfaces. Density functional theory (DFT) and many-body GW methods...and the band structure for bulk TiN were shown to be consistent with previous work. Calculated dielectric functions, plasma frequencies, reflectivity
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-29
...) number and a Taxpayer Identification Number (TIN); b. Register both your DUNS number and TIN with the... number and TIN on your application; and d. Maintain an active CCR registration with current information... a TIN from the Internal Revenue Service. If you are an individual, you can obtain a TIN from the...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-10
...) number and a Taxpayer Identification Number (TIN); b. Register both your DUNS number and TIN with the... number and TIN on your application; and d. Maintain an active CCR registration with current information... a TIN from the Internal Revenue Service. If you are an individual, you can obtain a TIN from the...
NASA Astrophysics Data System (ADS)
Schwartz, M. O.; Rajah, S. S.; Askury, A. K.; Putthapiban, P.; Djaswadi, S.
1995-07-01
The Southeast Asian Tin Belt is a north-south elongate zone 2800 km long and 400 km wide, extending from Burma (Myanmar) and Thailand to Peninsular Malaysia and the Indonesian Tin Islands. Altogether 9.6 million tonnes of tin, equivalent to 54% of the world's tin production is derived from this region. Most of the granitoids in the region can be grouped geographically into elongate provinces or belts, based on petrographic and geochronological features. - The Main Range Granitoid Province in western Peninsular Malaysia, southern Peninsular Thailand and central Thailand is almost entirely made up of biotite granite (184-230 Ma). Tin deposits associated with these granites contributed 55% of the historic tin production of Southeast Asia. - The Northern Granitoid Province in northern Thailand (0.1% of tin production) also has dominant biotite granite (200-269 Ma) but it is distinguished by abundant post-intrusion deformation. - The Eastern Granitoid Province extends from eastern Peninsular Malaysia to eastern Thailand. The Malaysian part is subdivided into the East Coast Belt (220-263 Ma), Boundary Range Belt (197-257 Ma) and Central Belt (79-219 Ma). The granitoids cover a wide compositional range from biotite granite to hornblende-biotite granite/granodiorite and diorite-gabbro. Tin deposits are associated with biotite granite in the East Coast Belt (3% of tin production). The granitoids in the other areas of the Eastern Granitoid Province are barren. - The Western Granitoid Province (22-149 Ma) in northern Peninsular Thailand, western Thailand and Burma has biotite granite and hornblende-biotite granite/granodiorite. Tin deposits are associated with biotite granite, which probably is the dominant phase (14% of tin production). The granitoids of the Indonesian Tin Islands (193-251 Ma) do not permit grouping into geographically distinct units. Main Range-type and Eastern Province-type plutons occur next to each other. Most of the tin deposits are associated with Main Range-type plutons (28% of tin production). Tin-mineralized plutons are characterized by high concentrations of SiO 2, K 2O, Rb, Sn, Th and U, whereas the concentrations of Fe 2O 3, MgO, CaO, Na 2O, Ba and Sr as well as the Fe2O3/FeO ratios are low. Tin-mineralized plutons are also distinguished by high initial 87Sr/86Sr ratios low magnetic susceptibilities.
Halide removal from aqueous solution by novel silver-polymeric materials.
A M S, Polo; I, Velo-Gala; M, Sánchez-Polo; U, von Gunten; J J, López-Peñalver; J, Rivera-Utrilla
2016-12-15
The objective of this study was to analyze the behavior of a new material, silver-doped polymeric cloth (Ag-cloth), in the removal of bromide and iodide from waters. Silver is immobilized on the cloth, guaranteeing selective adsorption of the halide ions as retained silver halides that therefore do not pass into the solution. Results indicate that Ag 0 reacts with H 2 O 2 in the first phases of the process, yielding Ag + and superoxide radical; however, as the process advances, this radical favors Ag + reduction. Increases in the concentration of H 2 O 2 augment the capacity of the Ag-cloth to remove halides from the medium up to a maximum concentration (55μM), above which the removal capacity remains constant (Xm≅1.3-1.8mg halide/g Ag-cloth). Thus, when there is excess H 2 O 2 in the medium, secondary competitive reactions that take place in the process guarantee a constant Ag + concentration, which defines the maximum adsorption capacity of Ag-cloth, reducing its ability to remove halides. Ag-cloth has a higher capacity to remove iodide than bromide, and the presence of organic matter or chloride reduces its capacity to remove iodide or bromide from water. The results obtained shown that the capacity of Ag 0 with H 2 O 2 significantly varies as a function of the medium pH from 1mg Br - /g Ag-cloth at very low pH to 1.6mg/g Ag-cloth at pH9. Copyright © 2016 Elsevier B.V. All rights reserved.
Myeloperoxidase-Halide-Hydrogen Peroxide Antibacterial System
Klebanoff, Seymour J.
1968-01-01
An antibacterial effect of myeloperoxidase, a halide, such as iodide, bromide, or chloride ion, and H2O2 on Escherichia coli or Lactobacillus acidophilus is described. When L. acidophilus was employed, the addition of H2O2 was not required; however, the protective effect of catalase suggested that, in this instance, H2O2 was generated by the organisms. The antibacterial effect was largely prevented by preheating the myeloperoxidase at 80 C or greater for 10 min or by the addition of a number of inhibitors; it was most active at the most acid pH employed (5.0). Lactoperoxidase was considerably less effective than was myeloperoxidase when chloride was the halide employed. Myeloperoxidase, at high concentrations, exerted an antibacterial effect on L. acidophilus in the absence of added halide, which also was temperature- and catalase-sensitive. Peroxidase was extracted from intact guinea pig leukocytes by weak acid, and the extract with peroxidase activity had antibacterial properties which were similar, in many respects, to those of the purified preparation of myeloperoxidase. Under appropriate conditions, the antibacterial effect was increased by halides and by H2O2 and was decreased by catalase, as well as by cyanide, azide, Tapazole, and thiosulfate. This suggests that, under the conditions employed, the antibacterial properties of a weak acid extract of guinea pig leukocytes is due, in part, to its peroxidase content, particularly if a halide is present in the reaction mixture. A heat-stable antibacterial agent or agents also appear to be present in the extract. PMID:4970226
Li, Yingjie; Qiao, Xianliang; Zhang, Ya-Nan; Zhou, Chengzhi; Xie, Huaijun; Chen, Jingwen
2016-10-01
The occurrence of sulfonamide antibiotics (SAs) in estuarine waters urges insights into their environmental fate for ecological risk assessment. Although many studies focused on the photochemical behavior of SAs, yet the effects of halide ions relevant to estuarine and marine environments on their photodegradation have been poorly understood. Here, we investigated the effects of halide ions on the photodegradation of SAs with sulfapyridine, sulfamethazine, and sulfamethoxazole as representative compounds. Results showed that halide ions did not significantly impact the photodegradation of sulfapyridine and sulfamethoxazole, while they significantly promoted the photodegradation of sulfamethazine. Further experiments found that ionic strength applied with NaClO4 significantly enhanced the photodegradation of the SAs, which was attributed to the decreased quenching rate constant of the triplet-excited SAs ((3)SA(∗)). Compared with ionic strength, specific Cl(-) effects retarded the photodegradation of the SAs. Our study found that triplet-excited sulfamethazine can oxidize halide ions to produce halogen radicals, subsequently leading to the halogenation of sulfamethazine, which was confirmed by the identification of both chlorinated and brominated intermediates. These results indicate that halide ions play an important role in the photochemical behavior of some SAs in estuarine waters and seawater. The occurrence of halogenation for certain organic pollutants can be predicted by comparing the oxidation potentials of triplet-excited contaminants with those of halogen radicals. Our findings are helpful in understanding the photochemical behavior and assessing the ecological risks of SAs and other organic pollutants in estuarine and marine environment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Persistent dopants and phase segregation in organolead mixed-halide perovskites
Rosales, Bryan A.; Men, Long; Cady, Sarah D.; ...
2016-07-25
Organolead mixed-halide perovskites such as CH 3NH 3PbX 3–aX' a (X, X' = I, Br, Cl) are interesting semiconductors because of their low cost, high photovoltaic power conversion efficiencies, enhanced moisture stability, and band gap tunability. Using a combination of optical absorption spectroscopy, powder X-ray diffraction (XRD), and, for the first time, 207Pb solid state nuclear magnetic resonance (ssNMR), we probe the extent of alloying and phase segregation in these materials. Because 207Pb ssNMR chemical shifts are highly sensitive to local coordination and electronic structure, and vary linearly with halogen electronegativity and band gap, this technique can provide the truemore » chemical speciation and composition of organolead mixed-halide perovskites. We specifically investigate samples made by three different preparative methods: solution phase synthesis, thermal annealing, and solid phase synthesis. 207Pb ssNMR reveals that nonstoichiometric dopants and semicrystalline phases are prevalent in samples made by solution phase synthesis. We show that these nanodomains are persistent after thermal annealing up to 200 °C. Further, a novel solid phase synthesis that starts from the parent, single-halide perovskites can suppress phase segregation but not the formation of dopants. Our observations are consistent with the presence of miscibility gaps and spontaneous spinodal decomposition of the mixed-halide perovskites at room temperature. This underscores how strongly different synthetic procedures impact the nanostructuring and composition of organolead halide perovskites. In conclusion, better optoelectronic properties and improved device stability and performance may be achieved through careful manipulation of the different phases and nanodomains present in these materials.« less
ESI-MS of Cucurbituril Complexes Under Negative Polarity.
Rodrigues, Maria A A; Mendes, Débora C; Ramamurthy, Vaidhyanathan; Da Silva, José P
2017-11-01
Electrospray ionization mass spectrometry (ESI-MS) is a powerful tool to study host-guest supramolecular interactions. ESI-MS can be used for detailed gas-phase reactivity studies, to clarify the structure, or simply to verify the formation of complexes. Depending on the structure of the host and of the guest, negative and/or positive ESI are used. Here we report the unexpected formation of host-guest complexes between cucurbit[n]urils (n = 7, 8, CB[n]) and amine, styryl pyridine, and styryl pyridine dimer cations, under negative ESI. Non-complexed CB[n] form double charged halide (Br - , Cl - , F - ) adducts. Under negative ESI, halide ions interact with CB[n] outer surface hydrogen atoms. One to one host-guest complexes (1:1) of CB[n] with positive charged guests were also observed as single and double charged ions under negative ESI. The positive charge of guests is neutralized by ion-pairing with halide anions. Depending on the number of positive charges guests retain in the gas phase, one or two additional halide ions are required for neutralization. Complexes 1:2 of CB[8] with styryl pyridines retain two halide ions in the gas phase, one per guest. Styryl pyridine dimers form 1:1 complexes possessing a single extra halide ion and therefore a single positive charge. Negative ESI is sensitive to small structural differences between complexes, distinguishing between 1:2 complexes of styryl pyridine-CB[8] and corresponding 1:1 complexes with the dimer. Negative ESI gives simpler spectra than positive ESI and allows the determination of guest charge state of CB[n] complexes in the gas phase. Graphical Abstract ᅟ.
Persistent dopants and phase segregation in organolead mixed-halide perovskites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rosales, Bryan A.; Men, Long; Cady, Sarah D.
Organolead mixed-halide perovskites such as CH 3NH 3PbX 3–aX' a (X, X' = I, Br, Cl) are interesting semiconductors because of their low cost, high photovoltaic power conversion efficiencies, enhanced moisture stability, and band gap tunability. Using a combination of optical absorption spectroscopy, powder X-ray diffraction (XRD), and, for the first time, 207Pb solid state nuclear magnetic resonance (ssNMR), we probe the extent of alloying and phase segregation in these materials. Because 207Pb ssNMR chemical shifts are highly sensitive to local coordination and electronic structure, and vary linearly with halogen electronegativity and band gap, this technique can provide the truemore » chemical speciation and composition of organolead mixed-halide perovskites. We specifically investigate samples made by three different preparative methods: solution phase synthesis, thermal annealing, and solid phase synthesis. 207Pb ssNMR reveals that nonstoichiometric dopants and semicrystalline phases are prevalent in samples made by solution phase synthesis. We show that these nanodomains are persistent after thermal annealing up to 200 °C. Further, a novel solid phase synthesis that starts from the parent, single-halide perovskites can suppress phase segregation but not the formation of dopants. Our observations are consistent with the presence of miscibility gaps and spontaneous spinodal decomposition of the mixed-halide perovskites at room temperature. This underscores how strongly different synthetic procedures impact the nanostructuring and composition of organolead halide perovskites. In conclusion, better optoelectronic properties and improved device stability and performance may be achieved through careful manipulation of the different phases and nanodomains present in these materials.« less
SOLVENT-FREE SONOCHEMICAL PREPARATION OF IONIC LIQUIDS
An ultrasound-assisted preparation of a series of ambient temperature ionic liquids, 1-alkyl-3-methylimidazolium (AMIM) halides, that proceeds via efficient reaction of 1-methyl imidazole with alkyl halides/terminal dihalides under solvent-free conditions, is described.
Gray, Thomas G
2009-03-02
Same but different: DFT calculations on hexanuclear tungsten(II) halide clusters [W(6)X(8)X'(6)](2-) (X, X'=Cl, Br, I) indicate a breakdown in the isoelectronic analogy between themselves and the isostructural rhenium(III) chalcogenide clusters [Re(6)S(8)X(6)](4-) (see figure).The hexanuclear tungsten(II) halide clusters and the sulfido-halide clusters of rhenium(III) are subsets of a broad system of 24-electron metal-metal bonded assemblies that share a common structure. Tungsten(II) halide clusters and rhenium(III) sulfide clusters luminesce from triplet excited states upon ultraviolet or visible excitation; emission from both cluster series has been extensively characterized elsewhere. Reported here are density-functional theory studies of the nine permutations of [W(6)X(8)X'(6)](2-) (X, X'=Cl, Br, I). Ground-state properties including geometries, harmonic vibrational frequencies, and orbital energy-level diagrams, have been calculated. Comparison is made to the sulfide clusters of rhenium(III), of which [Re(6)S(8)Cl(6)](4-) is representative. [W(6)X(8)X'(6)](2-) and [Re(6)S(8)Cl(6)](4-) possess disparate electronic structures owing to the greater covalency of the metal-sulfur bond and hence of the [Re(6)S(8)](2+) core. Low-lying virtual orbitals are raised in energy in [Re(6)S(8)Cl(6)](4-) with the result that the LUMO+7 (or LUMO+8 in some cases) of tungsten(II) halide clusters is the LUMO of [Re(6)S(8)Cl(6)](4-) species. An inversion of the HOMO and HOMO-1 between the two cluster series also occurs. Time-dependent density-functional calculations using asymptotically correct functionals do not recapture the experimentally observed periodic trend in [W(6)X(14)](2-) luminescence (E(em) increasing in the order [W(6)Cl(14)](2-) < [W(6)Br(14)](2-) < [W(6)I(14)](2-)), predicting instead that emission energies decrease with incorporation of the heavier halides. This circumstance is either a gross failure of the time-dependent formalism of DFT or it indicates extensive multistate emission in [W(6)X(8)X'(6)](2-) clusters. The inapplicability of isoelectronic analogies between clusters of Group 6 and Group 7 is emphasized.
Mineral resource of the month: tin
Carlin, James F.
2011-01-01
Tin was one of the earliest-known metals. Because of its hardening effect on copper, tin was used in bronze implements as early as 3500 B.C. Bronze, a copper-tin alloy that can be sharpened and is hard enough to retain a cutting edge, was used during the Bronze Age in construction tools as well as weapons for hunting and war. The geographical separation between tin-producing and tin-consuming nations greatly influenced the patterns of early trade routes. Historians think that as early as 1500 B.C., Phoenicians traveled by sea to the Cornwall district of England to obtain tin. The pure metal was not used unalloyed until about 600 B.C.
Tin recycling in the United States in 1998
Carlin, James F.
2001-01-01
This materials flow study includes a description of tin supply and demand factors for the United States to illustrate the extent of tin recycling and to identify recycling trends. Understanding the flow of materials from source to ultimate disposition can assist in improving the management of the use of natural resources in a manner that is compatible with sound environmental practices. The quantity of tin recycled in 1998 as a percentage of apparent tin supply was estimated to be about 22%, and recycling efficiency was estimated to be 75%. Of the total tin consumed in products for the U.S. market in 1998, an estimated 12% was consumed in products where the tin was not recyclable (dissipative uses).
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Reductive spectrophotometry of divalent tin sensitization on soda lime glass
NASA Astrophysics Data System (ADS)
Bejugam, Vinith; Wei, Xingfei; Roper, D. Keith
2016-07-01
Rapid and facile evaluation of tin (II) sensitization could lead to improved understanding of metal deposition in electroless (EL) plating. This report used a balanced redox reaction between 3,3‧,5,5‧-tetramethylbenzidine dihydrochloride (TMB-HCL) and N-bromosuccinimide (NBS) to evaluate effects of sensitization conditions (i.e., sensitization time, analyte concentration, aqueous immersion, and acid content) on the accumulated mass of surface-associated divalent tin ion. The accumulated mass of tin (II) increased as the sensitization time increased up to 30 s in proportion to aqueous tin (II) chloride concentrations between 2.6 and 26 mM at a trifluoroacetic acid (TFA) content of 68 mM. The average mass peaked at 7.3 nanomoles (nmol) per cm2 after a 5 s aqueous immersion post-sensitization, and then decreased with increasing aqueous immersion post-sensitization. The total average tin (II) + tin (IV) accumulated on soda lime glass measured by inductively coupled plasma optical emission spectrometry (ICP-OES) was 17% higher at 30 s sensitization, suggesting a fraction of the tin (II) present may have oxidized to tin (IV). These results indicated that in situ spectrophotometric evaluation of tin (II) could support development of EL plating for electronics, catalysis, and solar cells.
NASA Astrophysics Data System (ADS)
Rustandi, Andi; Cahyadi, Agung; Taruli Siallagan, Sonia; Wafa' Nawawi, Fuad; Pratesa, Yudha
2018-01-01
Tin slag is a byproduct of tin ore smelting process which is rarely utilized. The main purpose of this work is to investigate the use of tin slag for concrete cement material application compared to the industrial Ordinary Portland Cement (OPC). Tin slag composition was characterized by XRD and XRF analysis. The characterization results showed the similar chemical composition of tin slag and OPC. It also revealed the semi crystalline structure of tin slag sample. Several electrochemical tests were performed to evaluate corrosion behavior of tin slag, OPC and various mixed composition of both materials and the addition of CaO. The corrosion behavior of OPC and tin slag were evaluated by using Cyclic Polarization, Electrochemical Impedance Spectroscopy (EIS) and Electrochemical Frequency Modulation (EFM) methods. Aqueous sodium chloride (NaCl) solution with 3.5% w.t concentration which similar to seawater was used as the electrolyte in this work. The steel specimen used as the reinforce bar (rebar) material of the concrete was carbon steel AISI 1045. The rebar was embedded in the concrete cement which composed of OPC and the various composition of tin slag including slag without addition of CaO and slag mixed with addition of 50 % CaO. The electrochemical tests results revealed that tin slag affected its corrosion behavior which becoming more active and increasing the corrosion rate as well as decreasing the electrochemical impedance.
Wang, Zhenwei; Al-Jawhari, Hala A; Nayak, Pradipta K; Caraveo-Frescas, J A; Wei, Nini; Hedhili, M N; Alshareef, H N
2015-04-20
In this report, both p- and n-type tin oxide thin-film transistors (TFTs) were simultaneously achieved using single-step deposition of the tin oxide channel layer. The tuning of charge carrier polarity in the tin oxide channel is achieved by selectively depositing a copper oxide capping layer on top of tin oxide, which serves as an oxygen source, providing additional oxygen to form an n-type tin dioxide phase. The oxidation process can be realized by annealing at temperature as low as 190 °C in air, which is significantly lower than the temperature generally required to form tin dioxide. Based on this approach, CMOS inverters based entirely on tin oxide TFTs were fabricated. Our method provides a solution to lower the process temperature for tin dioxide phase, which facilitates the application of this transparent oxide semiconductor in emerging electronic devices field.
Corrosion resistance and mechanical properties of titanium nitride plating on orthodontic wires.
Sugisawa, Haruki; Kitaura, Hideki; Ueda, Kyosuke; Kimura, Keisuke; Ishida, Masahiko; Ochi, Yumiko; Kishikawa, Akiko; Ogawa, Saika; Takano-Yamamoto, Teruko
2018-03-30
Titanium nitride (TiN) coating by ion plating has properties such as high hardness, wear resistance, corrosion resistance, and surface lubricity, therefore TiN coating is often used in various dental appliances and materials. In this study, we evaluated the corrosion behaviors and mechanical properties of TiN coated stainless steel (SS) and nickel titanium (Ni-Ti) orthodontic wires prepared by ion plating. TiN coating by ion plating improves the corrosion resistance of orthodontic wires. The corrosion pitting of the TiN coated wire surface become small. The tensile strength and stiffness of SS wire were increased after TiN coating. In contrast, its elastic force, which is a property for Ni-Ti wire, was decreased. In addition, TiN coating provided small friction forces. The low level of friction may increase tooth movement efficiently. Therefore, TiN coated SS wire could be useful for orthodontics treatment.
Wang, Zhenwei; Al-Jawhari, Hala A.; Nayak, Pradipta K.; Caraveo-Frescas, J. A.; Wei, Nini; Hedhili, M. N.; Alshareef, H. N.
2015-01-01
In this report, both p- and n-type tin oxide thin-film transistors (TFTs) were simultaneously achieved using single-step deposition of the tin oxide channel layer. The tuning of charge carrier polarity in the tin oxide channel is achieved by selectively depositing a copper oxide capping layer on top of tin oxide, which serves as an oxygen source, providing additional oxygen to form an n-type tin dioxide phase. The oxidation process can be realized by annealing at temperature as low as 190°C in air, which is significantly lower than the temperature generally required to form tin dioxide. Based on this approach, CMOS inverters based entirely on tin oxide TFTs were fabricated. Our method provides a solution to lower the process temperature for tin dioxide phase, which facilitates the application of this transparent oxide semiconductor in emerging electronic devices field. PMID:25892711
Vibration-Resistant Support for Halide Lamps
NASA Technical Reports Server (NTRS)
Kiss, J.
1987-01-01
Lamp envelope protected against breakage. Old and new mounts for halide arc lamp sealed in housing with parabolic refector and quartz window. New version supports lamp with compliant garters instead of rigid brazed joint at top and dimensionally unstable finger stock at bottom.
Theoretical Studies in Chemical Kinetics - Annual Report, 1970.
DOE R&D Accomplishments Database
Karplus, Martin
1970-10-01
The research performed includes (a) Alkali-Halide, Alkali-Halide (MX, M?X?) Exchange Reactions; (b) Inversion Problem; (c) Quantum Mechanics of Scattering Processes, (d) Transition State Analysis of Classical Trajectories, (e) Differential Cross Sections from Classical Trajectories; and (f) Other Studies.
Methods for synthesizing alane without the formation of adducts and free of halides
Zidan, Ragaiy; Knight, Douglas A; Dinh, Long V
2013-02-19
A process is provided to synthesize an alane without the formation of alane adducts as a precursor. The resulting product is a crystallized .alpha.-alane and is a highly stable product and is free of halides.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dirian, J.; Saint-James, R.
1959-01-01
A collection is presented of references dealing with the physicochemical studies of fused salts, in partictular the alkali and alkali earth halides. Numerous binary, ternary and quaternary systems of these halides with those of uranium and thoriuna are examined, and the physical properties, density, viscosity, and vapor pressure going from the halides to the mixtures are also considered. References relating to the corrosion of materials by these salts are included and the treatment of the salts with a view to recovery after irradiation in a nuclear reactor is discussed. (auth)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sudheer,, E-mail: sudheer@rrcat.gov.in; Tiwari, P.; Rai, V. N.
The plasmonic responses of silver nanoparticles extracted from silver halide based electron microscope film are investigated. Photo-reduction process is carried out to convert the silver halide grains into the metallic silver. The centrifuge technique is used for separating the silver nanoparticles from the residual solution. Morphological study performed by field emission scanning electron microscope (FESEM) shows that all the nanoparticles have an average diameter of ~120 nm with a high degree of mono dispersion in size. The localized surface plasmon resonance (LSPR) absorption peak at ~537 nm confirms the presence of large size silver nanoparticles.
Plasmonic particles of colloidal silver in high-resolution recording media
NASA Astrophysics Data System (ADS)
Andreeva, O. V.; Andreeva, N. V.; Kuzmina, T. B.
2017-01-01
The optical properties of colloidal silver particles formed photographically in high-resolution silver halide photographic materials have been considered. The conditions that allow one to obtain exposed and developed light-sensitive silver halide particles in the form of colloidal particles of metallic silver having the properties of localized plasmons have been described. The results of the studies of the developed silver particles in traditional photographic materials for image holography and in nanoporous silver halide photographic materials for volume holography have been presented. The perspectives of using plasmonic silver nanoparticles produced photographically have been discussed.
Mahmoud, Abdallah G; Guedes da Silva, M Fátima C; Sokolnicki, Jerzy; Smoleński, Piotr; Pombeiro, Armando J L
2018-05-16
New hydrosoluble and air-stable Cu(i) halide compounds, viz. [CuX(DAPTA)3] (1) and (2), and [Cu(μ-X)(DAPTA)2]2 (3) and (4) (X = Br or I, in this order), have been prepared by reacting Cu(i) halide (i.e., bromide or iodide) with 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane (DAPTA) under mild conditions. They represent the first examples of Cu(i) halide complexes bearing the DAPTA ligand, which have been fully characterized by elemental analysis, IR, 1H, 13C{1H} and 31P{1H} NMR spectroscopies, ESI-MS+ and, for 4, also by single-crystal X-ray diffraction (SCXRD) analyses. Complexes 1-4 are efficient catalysts for the one-pot microwave assisted three-component (terminal alkyne, organic halide and NaN3) Huisgen cycloaddition reaction in aqueous media to afford the corresponding disubstituted triazoles. The catalysis proceeds with a broad alkyne substrate scope and according to "click rules". Photophysical studies of compound 4 showed an unusual reversible thermochromic behaviour exhibiting a blue emission at 298 K due to the halide-to-ligand charge transfer (3XLCT) and a red emission at 77 K because of the {Cu2I2} unit.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, L. B.; Donohoe, S. P.; Jones, M. H.
This article reports on the testing and comparison of a prototype hydrogen fuel cell light tower (H2LT) and a conventional diesel-powered metal halide light trailer for use in road maintenance and construction activities. The prototype was originally outfitted with plasma lights and then with light-emitting diode (LED) luminaires. Light output and distribution, lighting energy efficiency (i.e., efficacy), power source thermal efficiency, and fuel costs are compared. The metal halide luminaires have 2.2 and 3.1 times more light output than the plasma and LED luminaires, respectively, but they require more power/lumen to provide that output. The LED luminaires have 1.6 timesmore » better light efficacy than either the metal halide or plasma luminaires. The light uniformity ratios produced by the plasma and LED towers are acceptable. The fuel cell thermal efficiency at the power required to operate the plasma lights is 48%, significantly higher than the diesel generator efficiency of 23% when operating the metal halide lights. Due to the increased efficiency of the fuel cell and the LED lighting, the fuel cost per lumen-hour of the H2LT is 62% of the metal halide diesel light tower assuming a kilogram of hydrogen is twice the cost of a gallon of diesel fuel.« less
Determination of the structural phase and octahedral rotation angle in halide perovskites
dos Reis, Roberto; Yang, Hao; Ophus, Colin; ...
2018-02-12
A key to the unique combination of electronic and optical properties in halide perovskite materials lies in their rich structural complexity. However, their radiation sensitive nature limits nanoscale structural characterization requiring dose efficient microscopic techniques in order to determine their structures precisely. In this work, we determine the space-group and directly image the Br halide sites of CsPbBr 3, a promising material for optoelectronic applications. Based on the symmetry of high-order Laue zone reflections of convergent-beam electron diffraction, we identify the tetragonal (I4/mcm) structural phase of CsPbBr 3 at cryogenic temperature. Electron ptychography provides a highly sensitive phase contrast measurementmore » of the halide positions under low electron-dose conditions, enabling imaging of the elongated Br sites originating from the out-of-phase octahedral rotation viewed along the [001] direction of I4/mcm persisting at room temperature. The measurement of these features and comparison with simulations yield an octahedral rotation angle of 6.5°(±1.5°). Finally, the approach demonstrated here opens up opportunities for understanding the atomic scale structural phenomena applying advanced characterization tools on a wide range of radiation sensitive halide-based all-inorganic and hybrid organic-inorganic perovskites.« less
Stone, Emma Louise; Wakefield, Andrew; Harris, Stephen; Jones, Gareth
2015-01-01
Artificial light at night is a major feature of anthropogenic global change and is increasingly recognized as affecting biodiversity, often negatively. On a global scale, newer technology white lights are replacing orange sodium lights to reduce energy waste. In 2009, Cornwall County Council (UK) commenced replacement of existing low-pressure sodium (LPS) high intensity discharge (HID) street lights with new Phillips CosmoPolis white ceramic metal halide street lights to reduce energy wastage. This changeover provided a unique collaborative opportunity to implement a before-after-control-impact field experiment to investigate the ecological effects of newly installed broad spectrum light technologies. Activity of the bat species Pipistrellus pipistrellus, P. pygmaeus and Nyctalus/Eptesicus spp. was significantly higher at metal halide than LPS lights, as found in other studies of bat activity at old technology (i.e. mercury vapour) white light types. No significant difference was found in feeding attempts per bat pass between light types, though more passes overall were recorded at metal halide lights. Species-specific attraction of bats to the metal halide lights could have cascading effects at lower trophic levels. We highlight the need for further research on possible ecosystem-level effects of light technologies before they are installed on a wide scale. PMID:25780239
Fractionation of Cl/Br during fluid phase separation in magmatic-hydrothermal fluids
NASA Astrophysics Data System (ADS)
Seo, Jung Hun; Zajacz, Zoltán
2016-06-01
Brine and vapor inclusions were synthesized to study Cl/Br fractionation during magmatic-hydrothermal fluid phase separation at 900 °C and pressures of 90, 120, and 150 MPa in Li/Na/K halide salt-H2O systems. Laser ablation ICP-MS microanalysis of high-density brine inclusions show an elevated Cl/Br ratio compared to the coexisting low-density vapor inclusions. The degree of Cl/Br fractionation between vapor and brine is significantly dependent on the identity of the alkali metal in the system: stronger vapor partitioning of Br occurs in the Li halide-H2O system compared to the systems of K and Na halide-H2O. The effect of the identity of alkali-metals in the system is stronger compared to the effect of vapor-brine density contrast. We infer that competition between alkali-halide and alkali-OH complexes in high-temperature fluids might cause the Cl/Br fractionation, consistent with the observed molar imbalances of alkali metals compared to halides in the analyzed brine inclusions. Our experiments show that the identity of alkali metals controls the degrees of Cl/Br fractionation between the separating aqueous fluid phases at 900 °C, and suggest that a significant variability in the Cl/Br ratios of magmatic fluids can arise in Li-rich systems.
The Prognostic Value of Tumor-Infiltrating Neutrophils in Gastric Adenocarcinoma after Resection
Wang, Wei; Chen, Ju-gao; Wu, Yan-heng; Lv, Lin; Li, Jian-jun; Chen, Yi-bing; Wang, Dan-dan; Pan, Qiu-zhong; Li, Xiao-dong; Xia, Jian-chuan
2012-01-01
Background Several pieces of evidence indicate that tumor-infiltrating neutrophils (TINs) are correlated to tumor progression. In the current study, we explore the relationship between TINs and clinicopathological features of gastric adenocarcinoma patients. Furthermore, we investigated the prognostic value of TINs. Patients and Methods The study was comprised of two groups, training group (115 patients) and test group (97 patients). Biomarkers (intratumoral CD15+ neutrophils) were assessed by immunohistochemistry. The relationship between clinicopathological features and patient outcome were evaluated using Cox regression and Kaplan-Meier analysis. Results Immunohistochemical detection showed that the tumor-infiltrating neutrophils (TINs) in the training group ranged from 0.00–115.70 cells/high-power microscopic field (HPF) and the median number was 21.60 cells/HPF. Based on the median number, the patients were divided into high and low TINs groups. Chi-square test analysis revealed that the density of CD15+ TINs was positively associated with lymph node metastasis (p = 0.024), distance metastasis (p = 0.004) and UICC (International Union Against Cancer) staging (p = 0.028). Kaplan-Meier analysis showed that patients with a lower density of TINs had a better prognosis than patients with a higher density of TINs (p = 0.002). Multivariate Cox's analysis showed that the density of CD15+ TINs was an independent prognostic factor for overall survival of gastric adenocarcinoma patients. Using another 97 patients as a test group and basing on the median number of TINs (21.60 cells/HPF) coming from the training group, Kaplan-Meier analysis also showed that patients with a lower density of TINs had a better prognosis than patients with a higher density of TINs (p = 0.032). The results verify that the number of CD15+ TINs can predict the survival of gastric adenocarcinoma surgical patients. Conclusions The presence of CD15+ TINs is an independent and unfavorable factor in the prognosis of gastric adenocarcinoma patients. Targeting CD15+ TINs may be a potential intervenient therapy in the future. PMID:22442706
Moeller, Carina; Evers, Jochem B; Rebetzke, Greg
2014-01-01
Tillering is a core constituent of plant architecture, and influences light interception to affect plant and crop performance. Near-isogenic lines (NILs) varying for a tiller inhibition (tin) gene and representing two genetic backgrounds were investigated for tillering dynamics, organ size distribution, leaf area, light interception, red: far-red ratio, and chlorophyll content. Tillering ceased earlier in the tin lines to reduce the frequencies of later primary and secondary tillers compared to the free-tillering NILs, and demonstrated the genetically lower tillering plasticity of tin-containing lines. The distribution of organ sizes along shoots varied between NILs contrasting for tin. Internode elongation commenced at a lower phytomer, and the peduncle was shorter in the tin lines. The flag leaves of tin lines were larger, and the longest leaf blades were observed at higher phytomers in the tin than in free-tillering lines. Total leaf area was reduced in tin lines, and non-tin lines invested more leaf area at mid-canopy height. The tiller economy (ratio of seed-bearing shoots to numbers of shoots produced) was 10% greater in the tin lines (0.73-0.76) compared to the free-tillering sisters (0.62-0.63). At maximum tiller number, the red: far-red ratio (light quality stimulus that is thought to induce the cessation of tillering) at the plant-base was 0.18-0.22 in tin lines and 0.09-0.11 in free-tillering lines at levels of photosynthetic active radiation of 49-53% and 30-33%, respectively. The tin lines intercepted less radiation compared to their free-tillering sisters once genotypic differences in tiller numbers had established, and maintained green leaf area in the lower canopy later into the season. Greater light extinction coefficients (k) in tin lines prior to, but reduced k after, spike emergence indicated that differences in light interception between NILs contrasting in tin cannot be explained by leaf area alone but that geometric and optical canopy properties contributed. The careful characterization of specifically-developed NILs is refining the development of a physiology-based model for tillering to improve understanding of the value of architectural traits for use in cereal improvement.
Zhou, Lin; Xu, Le; Chen, Lingli; Fu, Qiang; Liu, Zheng; Chang, Yuan; Lin, Zongming; Xu, Jiejie
2017-01-01
Growing evidence shows tumor-infiltrating neutrophils (TINs) involvement in tumorigenesis. The objective of this study is to assess the prognostic effect of TINs and its impact on adjuvant chemotherapy benefits in muscle invasive bladder cancer (MIBC). A total of 142 MIBC patients from Zhongshan Hospital, 119 MIBC patients from FUSCC, and 405 MIBC patients from TCGA cohort were enrolled in the study. TINs were evaluated by immunohistochemical staining of CD66b or the CIBERSORT method. Patients with high TINs had a significantly poorer overall survival ( p = 0.001, p < 0.001, and p = 0.002, respectively) in the three sets. In the multivariate analysis, the presence of high TINs (HR = 2.122, p = 0.007; HR = 3.807, p < 0.001; HR = 2.104, p = 0.001; respectively) was identified as an independent prognostic factor for overall survival in the three sets. More importantly, Low TINs patients had significantly longer overall survival in patients without ACT in the three sets. Gene set enrichment analysis showed that lymphocyte activation ( p < 0.001) and T cell activation ( p = 0.008) were significantly enriched in the low TINs group. In addition, TINs were negatively correlated with CD8 + T cells, suggesting that the status of high-TINs was linked to the status of immunosuppression in MIBC. TINs could be used as independent prognostic factor. Low TINs identified a subgroup of MIBC patients who appeared to benefit from adjuvant chemotherapy. Incorporation of TINs into TNM system could further stratify patients with different prognosis.
Zhou, Lin; Xu, Le; Chen, Lingli; Fu, Qiang; Liu, Zheng; Chang, Yuan; Lin, Zongming; Xu, Jiejie
2017-01-01
ABSTRACT Growing evidence shows tumor-infiltrating neutrophils (TINs) involvement in tumorigenesis. The objective of this study is to assess the prognostic effect of TINs and its impact on adjuvant chemotherapy benefits in muscle invasive bladder cancer (MIBC). A total of 142 MIBC patients from Zhongshan Hospital, 119 MIBC patients from FUSCC, and 405 MIBC patients from TCGA cohort were enrolled in the study. TINs were evaluated by immunohistochemical staining of CD66b or the CIBERSORT method. Patients with high TINs had a significantly poorer overall survival (p = 0.001, p < 0.001, and p = 0.002, respectively) in the three sets. In the multivariate analysis, the presence of high TINs (HR = 2.122, p = 0.007; HR = 3.807, p < 0.001; HR = 2.104, p = 0.001; respectively) was identified as an independent prognostic factor for overall survival in the three sets. More importantly, Low TINs patients had significantly longer overall survival in patients without ACT in the three sets. Gene set enrichment analysis showed that lymphocyte activation (p < 0.001) and T cell activation (p = 0.008) were significantly enriched in the low TINs group. In addition, TINs were negatively correlated with CD8+ T cells, suggesting that the status of high-TINs was linked to the status of immunosuppression in MIBC. TINs could be used as independent prognostic factor. Low TINs identified a subgroup of MIBC patients who appeared to benefit from adjuvant chemotherapy. Incorporation of TINs into TNM system could further stratify patients with different prognosis. PMID:28507798
Skovager, Anne; Whitehead, Kathryn; Wickens, David; Verran, Joanna; Ingmer, Hanne; Arneborg, Nils
2013-09-01
Magnetron sputtering was used to produce nanocomposite TiN and TiN/Ag coatings on stainless steel surfaces. The surface chemistry (EDX), physicochemical properties (contact angles), topography and roughness parameters (WLP and AFM) of the fine polished stainless steel (FPSS), TiN and TiN/8.6 at.% Ag surfaces were examined. Real-time initial adhesion of two Listeria monocytogenes strains (EGDe and 64) to the three surfaces was determined under flow conditions, and their attachment strength after adhesion was measured using atomic force microscopy (AFM). The anti-listerial properties of the surfaces were determined using LIVE/DEAD staining. Our results demonstrate that FPSS, TiN and TiN/8.6 at.% Ag possessed different surface properties, which may influence both attachment strength and anti-listerial properties. There were no significant (p>0.05) differences in the initial adhesion of the two L. monocytogenes strains to the three different surfaces. Attachment studies showed that the two L. monocytogenes strains did not attach to FPSS under wetted conditions. However, both strains attached to TiN and TiN/8.6 at.% Ag surfaces, although with less strength to TiN/8.6 at.% Ag than to TiN surfaces. The TiN/8.6 at.% Ag surface showed marked anti-listerial properties as compared with FPSS and TiN. Initial adhesion, attachment strength and anti-listerial properties were found to be strain dependent. Copyright © 2013 Elsevier B.V. All rights reserved.
Tin recovery from tin slag using electrolysis method
NASA Astrophysics Data System (ADS)
Jumari, Arif; Purwanto, Agus; Nur, Adrian; Budiman, Annata Wahyu; Lerian, Metty; Paramita, Fransisca A.
2018-02-01
The process in industry, including in mining industry, would surely give negative effect such as waste polluting to the environment. Some of waste could be potentially reutilized to be a commodity with the higher economic value. Tin slag is one of them. The aim of this research was to recover the tin contained in tin slag. Before coming to the electrolysis, tin slag must be treated by dissolution. The grinded tin slag was dissolved into HCl solution to form a slurry. During dissolution, the slurry was agitated and heated, and finally filtered. The filtrate obtained was then electrolyzed. During the process of electrolysis, solid material precipitated on the used cathode. The precipitated solid was then separated and dried. The solid was then analyzed using XRD, XRF and SEM. The XRD analysis showed that the longest time of dissolution and electrolysis the highest the purity obtained in the product. The SEM analysis showed that the longest time of electrolysis the smallest tin particle obtained. Optimum time achieved in this research was 2 hours for the recovering time and 3 hours for the electrolysis time, with 9% tin recovered.
Zanon, Carlo; Tonini, Gian Paolo
2017-11-01
Chromosome instability has a pivotal role among the hallmarks of cancer, but its transcriptional counterpart is rarely considered a relevant factor in cell destabilization. To examine transcription instability (TIN), we first devised a metric we named TIN index and used it to evaluate TIN on a dataset containing more than 500 neuroblastoma samples. We found that metastatic tumors from high-risk (HR) patients are characterized by significantly different TIN index values compared to low/intermediate-risk patients. Our results indicate that the TIN index is a good predictor of neuroblastoma patient's outcome, and a related TIN index gene signature (TIN-signature) is also able to predict the neuroblastoma patient's outcome with high confidence. Interestingly, we find that TIN-signature genes have a strong positional association with superenhancers in neuroblastoma tumors. Finally, we show that TIN is linked to chromatin structural domains and interferes with their integrity in HR neuroblastoma patients. This novel approach to gene expression analysis broadens the perspective of genome instability investigations to include functional aspects. © 2017 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.
Carlin, James F.
2005-01-01
Tin was one of the first metals discovered by humans and, like most metals, tin is rarely used by itself. Most tin is used as a protective coating or as an alloy with other metals in a diverse range of commercial and defense applications.
NASA Technical Reports Server (NTRS)
Chamberlin, R.
2002-01-01
TIN is short for 'triangulated irregular network,' which is a piecewise planar model of a surface. If properly constructed, a TIN can be more than 30 times as efficient as a regular triangulation. In our project (a ground combat simulation to support U.S. Army training exercises), the TIN is used to represent the Earth's surface and is used primarily to determine whether line of sight is blocked by terrain. High efficiency requires accurate identification of ridgelines with as few triangles as possible. The work currently in progress is the implementation of a TINning process that we hope will produce superlative TINs. This presentation describes that process.
Tin whiskers in electronic circuits
NASA Astrophysics Data System (ADS)
Stupian, Gary W.
1992-12-01
Fibrous, conducting 'whiskers' often grow on pure tin plating. These tin whiskers have, for many years, been known to pose a reliability problem in electronic circuitry; therefore, the use of pure tin coatings in any critical electronic application is not recommended. Despite the warnings of the experts, tin plating is still found on electronic and mechanical components and problems with whiskers still arise. This document summarizes what is known about the growth of tin whiskers. A number of factors (e.g., coating thickness, plating conditions) are thought to be important in determining whether whiskers will grow. Although tin whiskers have been investigated from some decades, there is still disagreement on the effects of virtually every coating parameter. There is no disagreement, however, on the essential fact that it is very difficult to predict with certainty whether whiskers will grow on any specific tin-plated component, which of course is the basis of the 'experts' advice not to use pure tin plating. If tin-plated components are found in an electronic system, replacement is the safest policy. Some additional recommendations to minimize risk are presented here that may be of use in situations in which replacement of all suspect components is not the option of choice because of cost or schedule constraints.
Maximizing and stabilizing luminescence from halide perovskites with potassium passivation
NASA Astrophysics Data System (ADS)
Abdi-Jalebi, Mojtaba; Andaji-Garmaroudi, Zahra; Cacovich, Stefania; Stavrakas, Camille; Philippe, Bertrand; Richter, Johannes M.; Alsari, Mejd; Booker, Edward P.; Hutter, Eline M.; Pearson, Andrew J.; Lilliu, Samuele; Savenije, Tom J.; Rensmo, Håkan; Divitini, Giorgio; Ducati, Caterina; Friend, Richard H.; Stranks, Samuel D.
2018-03-01
Metal halide perovskites are of great interest for various high-performance optoelectronic applications. The ability to tune the perovskite bandgap continuously by modifying the chemical composition opens up applications for perovskites as coloured emitters, in building-integrated photovoltaics, and as components of tandem photovoltaics to increase the power conversion efficiency. Nevertheless, performance is limited by non-radiative losses, with luminescence yields in state-of-the-art perovskite solar cells still far from 100 per cent under standard solar illumination conditions. Furthermore, in mixed halide perovskite systems designed for continuous bandgap tunability (bandgaps of approximately 1.7 to 1.9 electronvolts), photoinduced ion segregation leads to bandgap instabilities. Here we demonstrate substantial mitigation of both non-radiative losses and photoinduced ion migration in perovskite films and interfaces by decorating the surfaces and grain boundaries with passivating potassium halide layers. We demonstrate external photoluminescence quantum yields of 66 per cent, which translate to internal yields that exceed 95 per cent. The high luminescence yields are achieved while maintaining high mobilities of more than 40 square centimetres per volt per second, providing the elusive combination of both high luminescence and excellent charge transport. When interfaced with electrodes in a solar cell device stack, the external luminescence yield—a quantity that must be maximized to obtain high efficiency—remains as high as 15 per cent, indicating very clean interfaces. We also demonstrate the inhibition of transient photoinduced ion-migration processes across a wide range of mixed halide perovskite bandgaps in materials that exhibit bandgap instabilities when unpassivated. We validate these results in fully operating solar cells. Our work represents an important advance in the construction of tunable metal halide perovskite films and interfaces that can approach the efficiency limits in tandem solar cells, coloured-light-emitting diodes and other optoelectronic applications.
Kobayashi, Makoto; Akiho, Hiroyuki
2017-12-01
Electricity production from coal fuel with minimizing efficiency penalty for the carbon dioxide abatement will bring us sustainable and compatible energy utilization. One of the promising options is oxy-fuel type Integrated Gasification Combined Cycle (oxy-fuel IGCC) power generation that is estimated to achieve thermal efficiency of 44% at lower heating value (LHV) base and provide compressed carbon dioxide (CO 2 ) with concentration of 93 vol%. The proper operation of the plant is established by introducing dry syngas cleaning processes to control halide and sulfur compounds satisfying tolerate contaminants level of gas turbine. To realize the dry process, the bench scale test facility was planned to demonstrate the first-ever halide and sulfur removal with fixed bed reactor using actual syngas from O 2 -CO 2 blown gasifier for the oxy-fuel IGCC power generation. Design parameter for the test facility was required for the candidate sorbents for halide removal and sulfur removal. Breakthrough test was performed on two kinds of halide sorbents at accelerated condition and on honeycomb desulfurization sorbent at varied space velocity condition. The results for the both sorbents for halide and sulfur exhibited sufficient removal within the satisfactory short depth of sorbent bed, as well as superior bed conversion of the impurity removal reaction. These performance evaluation of the candidate sorbents of halide and sulfur removal provided rational and affordable design parameters for the bench scale test facility to demonstrate the dry syngas cleaning process for oxy-fuel IGCC system as the scaled up step of process development. Copyright © 2017 Elsevier Ltd. All rights reserved.
Halide peroxidase in tissues that interact with bacteria in the host squid Euprymna scolopes.
Small, A L; McFall-Ngai, M J
1999-03-15
An enzyme with similarities to myeloperoxidase, the antimicrobial halide peroxidase in mammalian neutrophils, occurs abundantly in the light organ tissue of Euprymna scolopes, a squid that maintains a beneficial association with the luminous bacterium Vibrio fischeri. Using three independent assays typically applied to the analysis of halide peroxidase enzymes, we directly compared the activity of the squid enzyme with that of human myeloperoxidase. One of these methods, the diethanolamine assay, confirmed that the squid peroxidase requires halide ions for its activity. The identification of a halide peroxidase in a cooperative bacterial association suggested that this type of enzyme can function not only to control pathogens, but also to modulate the interactions of host animals with their beneficial partners. To determine whether the squid peroxidase functions under both circumstances, we examined its distribution in a variety of host tissues, including those that typically interact with bacteria and those that do not. Tissues interacting with bacteria included those that have specific cooperative associations with bacteria (i.e., the light organ and accessory nidamental gland) and those that have transient nonspecific interactions with bacteria (i.e., the gills, which clear the cephalopod circulatory system of invading microorganisms). These bacteria-associated tissues were compared with the eye, digestive gland, white body, and ink-producing tissues, which do not typically interact directly with bacteria. Peroxidase enzyme assays, immunocytochemical localization, and DNA-RNA hybridizations showed that the halide-dependent peroxidase is consistently expressed in high concentration in tissues that interact bacteria. Elevated levels of the peroxidase were also found in the ink-producing tissues, which are known to have enzymatic pathways associated with antimicrobial activity. Taken together, these data suggest that the host uses a common biochemical response to the variety of types of associations that it forms with microorganisms.
Maximizing and stabilizing luminescence from halide perovskites with potassium passivation.
Abdi-Jalebi, Mojtaba; Andaji-Garmaroudi, Zahra; Cacovich, Stefania; Stavrakas, Camille; Philippe, Bertrand; Richter, Johannes M; Alsari, Mejd; Booker, Edward P; Hutter, Eline M; Pearson, Andrew J; Lilliu, Samuele; Savenije, Tom J; Rensmo, Håkan; Divitini, Giorgio; Ducati, Caterina; Friend, Richard H; Stranks, Samuel D
2018-03-21
Metal halide perovskites are of great interest for various high-performance optoelectronic applications. The ability to tune the perovskite bandgap continuously by modifying the chemical composition opens up applications for perovskites as coloured emitters, in building-integrated photovoltaics, and as components of tandem photovoltaics to increase the power conversion efficiency. Nevertheless, performance is limited by non-radiative losses, with luminescence yields in state-of-the-art perovskite solar cells still far from 100 per cent under standard solar illumination conditions. Furthermore, in mixed halide perovskite systems designed for continuous bandgap tunability (bandgaps of approximately 1.7 to 1.9 electronvolts), photoinduced ion segregation leads to bandgap instabilities. Here we demonstrate substantial mitigation of both non-radiative losses and photoinduced ion migration in perovskite films and interfaces by decorating the surfaces and grain boundaries with passivating potassium halide layers. We demonstrate external photoluminescence quantum yields of 66 per cent, which translate to internal yields that exceed 95 per cent. The high luminescence yields are achieved while maintaining high mobilities of more than 40 square centimetres per volt per second, providing the elusive combination of both high luminescence and excellent charge transport. When interfaced with electrodes in a solar cell device stack, the external luminescence yield-a quantity that must be maximized to obtain high efficiency-remains as high as 15 per cent, indicating very clean interfaces. We also demonstrate the inhibition of transient photoinduced ion-migration processes across a wide range of mixed halide perovskite bandgaps in materials that exhibit bandgap instabilities when unpassivated. We validate these results in fully operating solar cells. Our work represents an important advance in the construction of tunable metal halide perovskite films and interfaces that can approach the efficiency limits in tandem solar cells, coloured-light-emitting diodes and other optoelectronic applications.
Klotz, K H; Benz, R
1993-01-01
Stationary and kinetic experiments were performed on lipid bilayer membranes to study the mechanism of iodine- and bromine-mediated halide transport in detail. The stationary conductance data suggested that four different 1:1 complexes between I2 and Br2 and the halides I- and Br- were responsible for the observed conductance increase by iodine and bromine (I3-, I2Br-, Br2I-, and Br3-). Charge pulse experiments allowed the further elucidation of the transport mechanism. Only two of three exponential voltage relaxations predicted by the Läuger model could be resolved under all experimental conditions. This means that either the heterogeneous complexation reactions kR (association) and kD (dissociation) were too fast to be resolved or that the neutral carriers were always in equilibrium within the membrane. Experiments at different carrier and halide concentrations suggested that the translocation of the neutral carrier is much faster than the other processes involved in carrier-mediated ion transport. The model was modified accordingly. From the charge pulse data at different halide concentrations, the translocation rate constant of the complexed carriers, kAS, the dissociation constant, kD, and the total surface concentration of charged carriers, NAS, could be evaluated from one single charge pulse experiment. The association rate of the complex, kR, could be obtained in some cases from the plot of the stationary conductance data as a function of the halide concentration in the aqueous phase. The translocation rate constant, kAS, of the different complexes is a function of the image force and of the Born charging energy. It increases 5000-fold from Br3- to I3- because of an enlarged ion radius. PMID:8312500
Friction and wear of tin and tin alloys from minus 100 C to 150 C
NASA Technical Reports Server (NTRS)
Buckley, D. H.
1975-01-01
Sliding friction experiments were conducted with an iron (110) single-crystal pin sliding on single and polycrystalline tin and tin alloys. Specimens were examined at various ambient temperatures from -100 to 150 C. Applied loads varied from 1 to 50 grams, and sliding velocity was constant at 0.7 mm/min. Results indicate that the crystal transformation of tin influences the friction coefficient. Friction was higher for the diamond structure (gray tin) than it was for the body-centered tetragonal structure (white tin). Bismuth arrested the crystal transformation, which resulted in constant friction over the temperature range -100 to 150 C. Both copper and aluminum enhanced the kinetics of transformation, with aluminum producing a nearly twofold change in friction with the crystal transformation.
A review of tin oxide-based catalytic systems: Preparation, characterization and catalytic behavior
NASA Technical Reports Server (NTRS)
Hoflund, Gar B.
1987-01-01
This paper reviews the important aspects of the preparation, characterization and catalytic behavior of tin oxide-based catalytic systems including doped tin oxide, mixed oxides which contain tin oxide, Pt supported on tin oxide and Pt/Sn supported on alumina. These systems have a broad range of applications and are continually increasing in importance. However, due to their complex nature, much remains to be understood concerning how they function catalytically.
Contributions of Stress and Oxidation on the Formation of Whiskers in Pb-free Solders
2016-01-29
environmental factors influencing formation of tin whiskers on electrodeposited lead free, tin coatings over copper (or copper containing) substrates is the...Oxidation on the Formation of Whiskers in Pb‐free Solders,” WP-1754 15. SUBJECT TERMS Tin Whiskers, Residual Stress, Environmental Degradation 16...showing the surface of a tin film with whisker .................... 2 Figure 2: SEM Micrograph of Tin film on Copper Substrate cross-sectioned by FIB
Synthesis of triazole-based and imidazole-based zinc catalysts
Valdez, Carlos A.; Satcher, Jr., Joe H.; Aines, Roger D.; Baker, Sarah E.
2013-03-12
Various methods and structures of complexes and molecules are described herein related to a zinc-centered catalyst for removing carbon dioxide from atmospheric or aqueous environments. According to one embodiment, a method for creating a tris(triazolyl)pentaerythritol molecule includes contacting a pentaerythritol molecule with a propargyl halide molecule to create a trialkyne molecule, and contacting the trialkyne molecule with an azide molecule to create the tris(triazolyl)pentaerythritol molecule. In another embodiment, a method for creating a tris(imidazolyl)pentaerythritol molecule includes alkylating an imidazole 2-carbaldehyde molecule to create a monoalkylated aldehyde molecule, reducing the monoalkylated aldehyde molecule to create an alcohol molecule, converting the alcohol molecule to create an alkyl halide molecule using thionyl halide, and reacting the alkyl halide molecule with a pentaerythritol molecule to create a tris(imidazolyl)pentaerythritol molecule. In another embodiment, zinc is bound to the tris(triazolyl)pentaerythritol molecule to create a zinc-centered tris(triazolyl)pentaerythritol catalyst for removing carbon dioxide from atmospheric or aqueous environments.
Yb-doped large-mode-area laser fiber fabricated by halide-gas-phase-doping technique
NASA Astrophysics Data System (ADS)
Peng, Kun; Wang, Yuying; Ni, Li; Wang, Zhen; Gao, Cong; Zhan, Huan; Wang, Jianjun; Jing, Feng; Lin, Aoxiang
2015-06-01
In this manuscript, we designed a rare-earth-halide gas-phase-doping setup to fabricate a large-mode-area fiber for high power laser applications. YbCl3 and AlCl3 halides are evaporated, carried respectively and finally mixed with usual host gas material SiCl4 at the hot zone of MCVD system. Owing to the all-gas-phasing reaction process and environment, the home-made Yb-doped fiber preform has a homogeneous large core and modulated refractive index profile to keep high beam quality. The drawn fiber core has a small numerical aperture of 0.07 and high Yb concentration of 9500 ppm. By using a master oscillator power amplifier system, nearly kW-level (951 W) laser output power was obtained with a slope efficiency of 83.3% at 1063.8 nm, indicating the competition and potential of the halide-gas-phase-doping technique for high power laser fiber fabrication.
Deciphering Halogen Competition in Organometallic Halide Perovskite Growth
Keum, Jong Kahk; Ovchinnikova, Olga S.; Chen, Shiyou; ...
2016-03-01
Organometallic halide perovskites (OHPs) hold great promise for next-generation, low-cost optoelectronic devices. During the chemical synthesis and crystallization of OHP thin films a major unresolved question is the competition between multiple halide species (e.g. I-, Cl-, Br-) in the formation of the mixed halide perovskite crystals. Whether Cl- ions are successfully incorporated into the perovskite crystal structure or alternatively, where they are located, is not yet fully understood. Here, in situ X-ray diffraction measurements of crystallization dynamics are combined with ex situ TOF-SIMS chemical analysis to reveal that Br- or Cl- ions can promote crystal growth, yet reactive I- ionsmore » prevent them from incorporating into the lattice of the final perovskite crystal structure. The Cl- ions are located in the grain boundaries of the perovskite films. These findings significantly advance our understanding of the role of halogens during synthesis of hybrid perovskites, and provide an insightful guidance to the engineering of high-quality perovskite films, essential for exploring superior-performance and cost-effective optoelectronic devices.« less
DeRosa, Christopher A.; Kerr, Caroline; Fan, Ziyi; Kolpaczynska, Milena; Mathew, Alexander S.; Evans, Ruffin E.; Zhang, Guoqing; Fraser, Cassandra L.
2015-01-01
The dual-emissive properties of solid-state difluoroboron β-diketonate-poly(lactic acid) (BF2bdkPLA) materials have been utilized for biological oxygen sensing. In this work, BF2dbm(X)PLA materials were synthesized, where X = H, F, Cl, Br, and I. The effects of changing the halide substituent and PLA polymer chain length on the optical properties in dilute CH2Cl2 solutions and solid-state polymer films were studied. These luminescent materials show fluorescence, phosphorescence, and lifetime tunability on the basis of molecular weight, as well as lifetime modulation via the halide substituent. Short BF2dbm(Br)PLA (6.0 kDa) and both short and long BF2dbm(I)PLA polymers (6.0 or 20.3 kDa) have fluorescence and intense phosphorescence ideal for ratiometric oxygen sensing. The lighter halide-dye polymers with hydrogen, fluorine, and chlorine substitution have longer phosphorescence lifetimes and can be utilized as ultrasensitive oxygen sensors. Photostability was also analyzed for the polymer films. PMID:26480236
Role of Halides in the Ordered Structure Transitions of Heated Gold Nanocrystal Superlattices
2015-01-01
Dodecanethiol-capped gold (Au) nanocrystal superlattices can undergo a surprisingly diverse series of ordered structure transitions when heated (Goodfellow, B. W.; Rasch, M. R.; Hessel, C. M.; Patel, R. N.; Smilgies, D.-M.; Korgel, B. A. Nano Lett.2013, 13, 5710–5714). These are the result of highly uniform changes in nanocrystal size, which subsequently force a spontaneous rearrangement of superlattice structure. Here, we show that halide-containing surfactants play an essential role in these transitions. In the absence of any halide-containing surfactant, superlattices of dodecanethiol-capped (1.9-nm-diameter) Au nanocrystals do not change size until reaching about 190–205 °C, at which point the gold cores coalesce. In the presence of halide-containing surfactant, such as tetraoctylphosphonium bromide (TOPB) or tetraoctylammounium bromide (TOAB), the nanocrystals ripen at much lower temperature and superlattices undergo various ordered structure transitions upon heating. Chloride- and iodide-containing surfactants induce similar behavior, destabilizing the Au–thiol bond and reducing the thermal stability of the nanocrystals. PMID:26013597
Deciphering Halogen Competition in Organometallic Halide Perovskite Growth
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keum, Jong Kahk; Ovchinnikova, Olga S.; Chen, Shiyou
Organometallic halide perovskites (OHPs) hold great promise for next-generation, low-cost optoelectronic devices. During the chemical synthesis and crystallization of OHP thin films a major unresolved question is the competition between multiple halide species (e.g. I-, Cl-, Br-) in the formation of the mixed halide perovskite crystals. Whether Cl- ions are successfully incorporated into the perovskite crystal structure or alternatively, where they are located, is not yet fully understood. Here, in situ X-ray diffraction measurements of crystallization dynamics are combined with ex situ TOF-SIMS chemical analysis to reveal that Br- or Cl- ions can promote crystal growth, yet reactive I- ionsmore » prevent them from incorporating into the lattice of the final perovskite crystal structure. The Cl- ions are located in the grain boundaries of the perovskite films. These findings significantly advance our understanding of the role of halogens during synthesis of hybrid perovskites, and provide an insightful guidance to the engineering of high-quality perovskite films, essential for exploring superior-performance and cost-effective optoelectronic devices.« less
NASA Astrophysics Data System (ADS)
Kim, Jong Man; Choi, Byung So; Kim, Sun Il; Kim, Jong Min; Bjelkhagen, Hans I.; Phillips, Nicholas J.
2001-02-01
Silver halide sensitized gelatin (SHSG) holograms are similar to holograms recorded in dichromated gelatin (DCG), the main recording material for holographic optical elements (HOE s). The drawback of DCG is its low sensitivity and limited spectral response. Silver halide materials can be processed in such a way that the final hologram will have properties like a DCG hologram. Recently this technique has become more interesting since the introduction of new ultra-high-resolution silver halide emulsions. An optimized processing technique for transmission HOE s recorded in these materials is introduced. Diffraction efficiencies over 90% can be obtained for transmissive diffraction gratings. Understanding the importance of the selective hardening process has made it possible to obtain results similar to conventional DCG processing. The main advantage of the SHSG process is that high-sensitivity recording can be performed with laser wavelengths anywhere within the visible spectrum. This simplifies the manufacturing of high-quality, large-format HOE s.
Fluorescent Properties of Manganese Halide Benzothiazole Inorganic-Organic Hybrids.
Yu, Hui; Mei, YingXuan; Wei, ZhenHong; Mei, GuangQuan; Cai, Hu
2016-11-01
The reaction of manganese (II) halides MnX 2 and benzothiazole (btz) in the concentrated acids HX (X = Cl, Br) at 80 °C resulted in the formation of two inorganic-organic hybrid complexes: [(btz) 2 (MnX 4 )]·2H 2 O (X = Cl, 1; X = Br, 2). Both compounds showed green luminescence and exhibited moderate quantum yields of 43.17 % for 1 and 26.18 % for 2, which were directly originated from the tetrahedral coordination of Mn 2+ ion. Two organic - inorganic hybrids [(btz) 2 (MnX 4 )]·2H 2 O based on MnCl 2 , benzothiazole and halide acids emitted green light with the moderate quantum efficiencies when excited by 365 nm light. Graphical abstract Two organic-inorganic hybrids [(btz) 2 (MnX 4 )]·2H 2 O based on MnCl 2 , benzothiazole and halide acids emitted green light with the moderate quantum efficiencies when excited by 365 nm light.
Chen, Mingming; Shan, Xin; Geske, Thomas; Li, Junqiang; Yu, Zhibin
2017-06-27
Ion migration has been commonly observed as a detrimental phenomenon in organometal halide perovskite semiconductors, causing the measurement hysteresis in solar cells and ultrashort operation lifetimes in light-emitting diodes. In this work, ion migration is utilized for the formation of a p-i-n junction at ambient temperature in single-crystalline organometal halide perovskites. The junction is subsequently stabilized by quenching the ionic movement at a low temperature. Such a strategy of manipulating the ion migration has led to efficient single-crystalline light-emitting diodes that emit 2.3 eV photons starting at 1.8 V and sustain a continuous operation for 54 h at ∼5000 cd m -2 without degradation of brightness. In addition, a whispering-gallery-mode cavity and exciton-exciton interaction in the perovskite microplatelets have both been observed that can be potentially useful for achieving electrically driven laser diodes based on single-crystalline organometal halide perovskite semiconductors.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false TINs. 204.7202-3 Section... OF DEFENSE GENERAL ADMINISTRATIVE MATTERS Contractor Identification 204.7202-3 TINs. Requirements for use of TINs are in FAR subpart 4.9. [64 FR 43100, Aug. 9, 1999] ...
40 CFR 421.296 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin Subcategory... wastewater pollutants in secondary tin process wastewater introduced into a POTW shall not exceed the following values: (a) Tin smelter SO2 scrubber. PSNS for the Secondary Tin Subcategory Pollutant or...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false TINs. 204.7202-3 Section... OF DEFENSE GENERAL ADMINISTRATIVE MATTERS Contractor Identification 204.7202-3 TINs. Requirements for use of TINs are in FAR subpart 4.9. [64 FR 43100, Aug. 9, 1999] ...
40 CFR 421.296 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin Subcategory... wastewater pollutants in secondary tin process wastewater introduced into a POTW shall not exceed the following values: (a) Tin smelter SO2 scrubber. PSNS for the Secondary Tin Subcategory Pollutant or...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false TINs. 204.7202-3 Section... OF DEFENSE GENERAL ADMINISTRATIVE MATTERS Contractor Identification 204.7202-3 TINs. Requirements for use of TINs are in FAR subpart 4.9. [64 FR 43100, Aug. 9, 1999] ...
40 CFR 421.296 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin Subcategory... wastewater pollutants in secondary tin process wastewater introduced into a POTW shall not exceed the following values: (a) Tin smelter SO2 scrubber. PSNS for the Secondary Tin Subcategory Pollutant or...
40 CFR 421.296 - Pretreatment standards for new sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin Subcategory... wastewater pollutants in secondary tin process wastewater introduced into a POTW shall not exceed the following values: (a) Tin smelter SO2 scrubber. PSNS for the Secondary Tin Subcategory Pollutant or...
40 CFR 421.296 - Pretreatment standards for new sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin Subcategory... wastewater pollutants in secondary tin process wastewater introduced into a POTW shall not exceed the following values: (a) Tin smelter SO2 scrubber. PSNS for the Secondary Tin Subcategory Pollutant or...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false TINs. 204.7202-3 Section... OF DEFENSE GENERAL ADMINISTRATIVE MATTERS Contractor Identification 204.7202-3 TINs. Requirements for use of TINs are in FAR subpart 4.9. [64 FR 43100, Aug. 9, 1999] ...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-25
... chemical substances rutile, tin zinc, calcium-doped (CAS No. 389623-01- 2) and rutile, tin zinc, sodium... substances rutile, tin zinc, calcium- doped (CAS No. 389623-01-2) and rutile, tin zinc, sodium-doped (CAS No...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false TINs. 204.7202-3 Section... OF DEFENSE GENERAL ADMINISTRATIVE MATTERS Contractor Identification 204.7202-3 TINs. Requirements for use of TINs are in FAR subpart 4.9. [64 FR 43100, Aug. 9, 1999] ...
NASA Astrophysics Data System (ADS)
Lei, Fengcai; Liu, Wei; Sun, Yongfu; Xu, Jiaqi; Liu, Katong; Liang, Liang; Yao, Tao; Pan, Bicai; Wei, Shiqiang; Xie, Yi
2016-09-01
Ultrathin metal layers can be highly active carbon dioxide electroreduction catalysts, but may also be prone to oxidation. Here we construct a model of graphene confined ultrathin layers of highly reactive metals, taking the synthetic highly reactive tin quantum sheets confined in graphene as an example. The higher electrochemical active area ensures 9 times larger carbon dioxide adsorption capacity relative to bulk tin, while the highly-conductive graphene favours rate-determining electron transfer from carbon dioxide to its radical anion. The lowered tin-tin coordination numbers, revealed by X-ray absorption fine structure spectroscopy, enable tin quantum sheets confined in graphene to efficiently stabilize the carbon dioxide radical anion, verified by 0.13 volts lowered potential of hydroxyl ion adsorption compared with bulk tin. Hence, the tin quantum sheets confined in graphene show enhanced electrocatalytic activity and stability. This work may provide a promising lead for designing efficient and robust catalysts for electrolytic fuel synthesis.
Platelet composite coatings for tin whisker mitigation
Rohwer, Lauren E. S.; Martin, James E.
2015-09-14
In this study, reliable methods for tin whisker mitigation are needed for applications that utilize tin-plated commercial components. Tin can grow whiskers that can lead to electrical shorting, possibly causing critical systems to fail catastrophically. The mechanisms of tin whisker growth are unclear and this makes prediction of the lifetimes of critical components uncertain. The development of robust methods for tin whisker mitigation is currently the best approach to eliminating the risk of shorting. Current mitigation methods are based on unfilled polymer coatings that are not impenetrable to tin whiskers. In this paper we report tin whisker mitigation results formore » several filled polymer coatings. The whisker-penetration resistance of the coatings was evaluated at elevated temperature and high humidity and under temperature cycling conditions. The composite coatings comprised Ni and MgF 2-coated Al/Ni/Al platelets in epoxy resin or silicone rubber. In addition to improved whisker mitigation, these platelet composites have enhanced thermal conductivity and dielectric constant compared with unfilled polymers.« less
Platelet Composite Coatings for Tin Whisker Mitigation
NASA Astrophysics Data System (ADS)
Rohwer, Lauren E. S.; Martin, James E.
2015-11-01
Reliable methods for tin whisker mitigation are needed for applications that utilize tin-plated commercial components. Tin can grow whiskers that can lead to electrical shorting, possibly causing critical systems to fail catastrophically. The mechanisms of tin whisker growth are unclear and this makes prediction of the lifetimes of critical components uncertain. The development of robust methods for tin whisker mitigation is currently the best approach to eliminating the risk of shorting. Current mitigation methods are based on unfilled polymer coatings that are not impenetrable to tin whiskers. In this paper we report tin whisker mitigation results for several filled polymer coatings. The whisker-penetration resistance of the coatings was evaluated at elevated temperature and high humidity and under temperature cycling conditions. The composite coatings comprised Ni and MgF2-coated Al/Ni/Al platelets in epoxy resin or silicone rubber. In addition to improved whisker mitigation, these platelet composites have enhanced thermal conductivity and dielectric constant compared with unfilled polymers.
Methyl halide fluxes from tropical plants under controlled radiation and temperature regimes
NASA Astrophysics Data System (ADS)
Blei, Emanuel; Yokouchi, Yoko; Saito, Takuya; Nozoe, Susumu
2015-04-01
Methyl halides (CH3Cl, CH3Br, CH3I) contribute significantly to the halogen burden of the atmosphere and have the potential to influence the stratospheric ozone layer through their catalytic effect in the Chapman cycle. As such they have been studied over the years, and many plants and biota have been examined for their potential to act as a source of these gases. One of the potentially largest terrestrial sources identified was tropical vegetation such as tropical ferns and Dipterocarp trees. Most of these studies concentrated on the identification and quantification of such fluxes rather than their characteristics and often the chambers used in these studies were either opaque or only partially transparent to the full solar spectrum. Therefore it is not certain to which degree emissions of methyl halides are innate to the plants and how much they might vary due to radiation or temperature conditions inside the enclosures. In a separate development it had been proposed that UV-radiation could cause live plant materials to be become emitters of methane even under non-anoxic conditions. As methane is chemically very similar to methyl halides and had been proposed to be produced from methyl-groups ubiquitously found in plant cell material there is a relatively good chance that such a production mechanism would also apply to methyl halides. To test whether radiation can affect elevated emissions of methyl halides from plant materials and to distinguish this from temperature effects caused by heat build-up in chambers a set of controlled laboratory chamber enclosures under various radiation and temperature regimes was conducted on four different tropical plant species (Magnolia grandiflora, Cinnamonum camphora, Cyathea lepifera, Angiopteris lygodiifolia), the latter two of which had previously been identified as strong methyl halide emitters. Abscised leaf samples of these species were subjected to radiation treatments such UV-B, UV-A and broad spectrum radiation similar to natural sunlight without the UV-component and the emissions were compared to dark enclosures. Parallel to this temperature effects were studied in dark enclosures as well. The presentation will discuss the outcome of these experiments and what conclusions can be drawn from them.
Polynucleotides encoding TRF1 binding proteins
Campisi, Judith; Kim, Sahn-Ho
2002-01-01
The present invention provides a novel telomere associated protein (Trf1-interacting nuclear protein 2 "Tin2") that hinders the binding of Trf1 to its specific telomere repeat sequence and mediates the formation of a Tin2-Trf1-telomeric DNA complex that limits telomerase access to the telomere. Also included are the corresponding nucleic acids that encode the Tin2 of the present invention, as well as mutants of Tin2. Methods of making, purifying and using Tin2 of the present invention are described. In addition, drug screening assays to identify drugs that mimic and/or complement the effect of Tin2 are presented.
Optical Properties and Plasmonic Performance of Titanium Nitride
Patsalas, Panos; Kalfagiannis, Nikolaos; Kassavetis, Spyros
2015-01-01
Titanium nitride (TiN) is one of the most well-established engineering materials nowadays. TiN can overcome most of the drawbacks of palsmonic metals due to its high electron conductivity and mobility, high melting point and due to the compatibility of its growth with Complementary Metal Oxide Semiconductor (CMOS) technology. In this work, we review the dielectric function spectra of TiN and we evaluate the plasmonic performance of TiN by calculating (i) the Surface Plasmon Polariton (SPP) dispersion relations and (ii) the Localized Surface Plasmon Resonance (LSPR) band of TiN nanoparticles, and we demonstrate a significant plasmonic performance of TiN.
Estimating the Probability of Electrical Short Circuits from Tin Whiskers. Part 2
NASA Technical Reports Server (NTRS)
Courey, Karim J.; Asfour, Shihab S.; Onar, Arzu; Bayliss, Jon A.; Ludwig, Larry L.; Wright, Maria C.
2009-01-01
To comply with lead-free legislation, many manufacturers have converted from tin-lead to pure tin finishes of electronic components. However, pure tin finishes have a greater propensity to grow tin whiskers than tin-lead finishes. Since tin whiskers present an electrical short circuit hazard in electronic components, simulations have been developed to quantify the risk of said short circuits occurring. Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that had an unknown probability associated with it. Note however that due to contact resistance electrical shorts may not occur at lower voltage levels. In our first article we developed an empirical probability model for tin whisker shorting. In this paper, we develop a more comprehensive empirical model using a refined experiment with a larger sample size, in which we studied the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From the resulting data we estimated the probability distribution of an electrical short, as a function of voltage.
NASA Astrophysics Data System (ADS)
Bae, Sang-Dae; Kwon, Soo-Hun; Jeong, Hwan-Seok; Kwon, Hyuck-In
2017-07-01
In this work, we investigated the effects of low-temperature argon (Ar)-plasma surface treatments on the physical and chemical structures of p-type tin oxide thin-films and the electrical performance of p-type tin oxide thin-film transistors (TFTs). From the x-ray photoelectron spectroscopy measurement, we found that SnO was the dominant phase in the deposited tin oxide thin-film, and the Ar-plasma treatment partially transformed the tin oxide phase from SnO to SnO2 by oxidation. The resistivity of the tin oxide thin-film increased with the plasma-treatment time because of the reduced hole concentration. In addition, the root-mean-square roughness of the tin oxide thin-film decreased as the plasma-treatment time increased. The p-type oxide TFT with an Ar-plasma-treated tin oxide thin-film exhibited excellent electrical performance with a high current on-off ratio (5.2 × 106) and a low off-current (1.2 × 10-12 A), which demonstrates that the low-temperature Ar-plasma treatment is a simple and effective method for improving the electrical performance of p-type tin oxide TFTs.
Aluminum Pitting Corrosion in Halide Media: A Quantum Model and Empirical Evidence
NASA Astrophysics Data System (ADS)
Lashgari, Mohsen; Kianpour, Effat; Mohammadi, Esmaeil
2013-12-01
The phenomenon of localized damage of aluminum oxide surface in the presence of halide anions was scrutinized at an atomistic level, through the cluster approach and density functional theory. The phenomenon was also investigated empirically through Tafel polarization plots and scanning electron microscopy. A distinct behavior witnessed in the fluoride medium was justified through the hard-soft acid-base principle. The atomistic investigations revealed the greatest potency for chloride entrance into the metal oxide lattice and rationalized to the severity of damage. The interaction of halide anions with the oxide surface causing some displacements on the position of Al atoms provides a mechanistic insight of the phenomenon.
PROCESS OF PRODUCING REFRACTORY URANIUM OXIDE ARTICLES
Hamilton, N.E.
1957-12-01
A method is presented for fabricating uranium oxide into a shaped refractory article by introducing a uranium halide fluxing reagent into the uranium oxide, and then mixing and compressing the materials into a shaped composite mass. The shaped mass of uranium oxide and uranium halide is then fired at an elevated temperature so as to form a refractory sintered article. It was found in the present invention that the introduction of a uraninm halide fluxing agent afforded a fluxing action with the uranium oxide particles and that excellent cohesion between these oxide particles was obtained. Approximately 90% of uranium dioxide and 10% of uranium tetrafluoride represent a preferred composition.
Reshaping and linking of molecules in ion-pair traps
NASA Astrophysics Data System (ADS)
Cochrane, Bryce; Naumkin, Fedor Y.
2016-01-01
A series of insertion complexes of small molecules trapped between alkali-halide counter-ions are investigated ab initio. The molecular shape is altered inside the complexes and varies in corresponding anions. Stabilities and charge distributions are investigated. Strong charge-transfer in the alkali-halide component effectively through the almost neutral molecule results in very large dipole moments. The most stable species is used to construct a dimer significantly bound via dipole-dipole interaction. Another complex with two alkali-halide diatoms trapping the molecule represents a unit of corresponding longer oligomer. This completes the array of systems with the molecule effectively in ion-pair, ion-dipole, dipole-pair electric fields.
High-Efficiency Flexible Solar Cells Based on Organometal Halide Perovskites.
Wang, Yuming; Bai, Sai; Cheng, Lu; Wang, Nana; Wang, Jianpu; Gao, Feng; Huang, Wei
2016-06-01
Flexible and light-weight solar cells are important because they not only supply power to wearable and portable devices, but also reduce the transportation and installation cost of solar panels. High-efficiency organometal halide perovskite solar cells can be fabricated by a low-temperature solution process, and hence are promising for flexible-solar-cell applications. Here, the development of perovskite solar cells is briefly discussed, followed by the merits of organometal halide perovskites as promising candidates as high-efficiency, flexible, and light-weight photovoltaic materials. Afterward, recent developments of flexible solar cells based on perovskites are reviewed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ding, Shunmin; Tian, Chengcheng; Zhu, Xiang; ...
2017-03-23
Transition-metal-catalyzed cyanation of aryl halides is a common route to benzonitriles, which are integral to many industrial procedures. However, traditional homogeneous catalysts for such processes are expensive and suffer poor recyclability, so a heterogeneous analogue is highly desired. A novel spatial modulation approach has been developed in this paper to fabricate a heterogeneous Pd-metalated nanoporous polymer, which catalyzes the cyanation of aryl halides without need for ligands. Finally, the catalyst displays high activity in the synthesis of benzonitriles, including high product yields, excellent stability and recycling, and broad functional-group tolerance.
Visible-Light-Promoted Trifluoromethylthiolation of Styrenes by Dual Photoredox/Halide Catalysis.
Honeker, Roman; Garza-Sanchez, R Aleyda; Hopkinson, Matthew N; Glorius, Frank
2016-03-18
Herein, we report a new visible-light-promoted strategy to access radical trifluoromethylthiolation reactions by combining halide and photoredox catalysis. This approach allows for the synthesis of vinyl-SCF3 compounds of relevance in pharmaceutical chemistry directly from alkenes under mild conditions with irradiation from household light sources. Furthermore, alkyl-SCF3-containing cyclic ketone and oxindole derivatives can be accessed by radical-polar crossover semi-pinacol and cyclization processes. Inexpensive halide salts play a crucial role in activating the trifluoromethylthiolating reagent towards photoredox catalysis and aid the formation of the SCF3 radical. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Allylic and Allenic Halide Synthesis via NbCl5- and NbBr5-Mediated Alkoxide Rearrangements
Ravikumar, P. C.; Yao, Lihua; Fleming, Fraser F.
2009-01-01
Addition of NbCl5, or NbBr5, to a series of magnesium, lithium, or potassium allylic or propargylic alkoxides directly provides allylic or allenic halides. Halogenation formally occurs through a metalla-halo-[3,3] rearrangement although concerted, ionic, and direct displacement mechanisms appear to operate competitively. Transposition of the olefin is equally effective for allylic alkoxides prepared by nucleophilic addition, deprotonation, or reduction. Experimentally, the niobium pentahalide halogenations are rapid, afford essentially pure E-allylic or allenic halides after extraction, and are applicable to a range of aliphatic and aromatic alcohols, aldehydes, and ketones. PMID:19739606
40 CFR 421.295 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin... existing sources. The mass of wastewater pollutants in secondary tin process wastewater introduced into a POTW must not exceed the following values: (a) Tin smelter SO2 scrubber. PSES for the Secondary Tin...
40 CFR 421.295 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin... existing sources. The mass of wastewater pollutants in secondary tin process wastewater introduced into a POTW must not exceed the following values: (a) Tin smelter SO2 scrubber. PSES for the Secondary Tin...
40 CFR 421.295 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin... existing sources. The mass of wastewater pollutants in secondary tin process wastewater introduced into a POTW must not exceed the following values: (a) Tin smelter SO2 scrubber. PSES for the Secondary Tin...
40 CFR 421.295 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin... existing sources. The mass of wastewater pollutants in secondary tin process wastewater introduced into a POTW must not exceed the following values: (a) Tin smelter SO2 scrubber. PSES for the Secondary Tin...
40 CFR 421.295 - Pretreatment standards for existing sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tin... existing sources. The mass of wastewater pollutants in secondary tin process wastewater introduced into a POTW must not exceed the following values: (a) Tin smelter SO2 scrubber. PSES for the Secondary Tin...
An Investigation of the Electrical Short Circuit Characteristics of Tin Whiskers
NASA Technical Reports Server (NTRS)
Courey, Karim J.
2008-01-01
In this experiment, an empirical model to quantify the probability of occurrence of an electrical short circuit from tin whiskers as a function of voltage was developed. This model can be used to improve existing risk simulation models FIB and TEM images of a tin whisker confirm the rare polycrystalline structure on one of the three whiskers studied. FIB cross-section of the card guides verified that the tin finish was bright tin.
Effect of Tin, Copper and Boron on the Hot Ductility of 20CrMnTi Steel between 650 °C and 1100 °C
NASA Astrophysics Data System (ADS)
Peng, Hong-bing; Chen, Wei-qing; Chen, Lie; Guo, Dong
2015-02-01
The hot ductility of 20CrMnTi steel with x% tin, y% copper and z ppm boron (x = 0, 0.02; y = 0, 0.2; z = 0, 60) was investigated. The results show that tin and copper in 20CrMnTi steel are detrimental to its hot ductility while adding boron can eliminate the adverse effect and enhance hot ductility greatly. Tin is found to segregate to the boundaries tested by EPMA in 20CrMnTi steel containing tin and copper and tin-segregation is suppressed by adding boron, moreover, copper was found not to segregate to boundaries, however, fine copper sulfide was found from carbon extraction replicas using TEM. The adverse effect of tin and copper on the hot ductility was due mainly to tin segregation and fine copper sulfide in the steel. The proeutectoid ferrite film precipitating along the austenite grain boundary causes the ductility trough of the three examined steels. Tin and copper in 20CrMnTi steel can retard the occurrence of dynamic recrystallization (DRX) while boron-addition can compensate for that change. The beneficial effect of boron on 20CrMnTi steel containing tin and copper might be ascribed to the fact that boron segregates to grain boundaries, accelerates onset of DRX, retards austenite/ferrite transformation and promotes intragranular nucleation of ferrite.
Precipitation Behaviors of TiN Inclusion in GCr15 Bearing Steel Billet
NASA Astrophysics Data System (ADS)
Tian, Qianren; Wang, Guocheng; Zhao, Yang; Li, Jing; Wang, Qi
2018-06-01
There are many types of non-metallic TiN-based inclusions observed in GCr15 bearing steel, including single-particle TiN, multi-particle polymerized TiN, and complex inclusions like TiN-MnS, TiN-MgO-MgAl2O4 (TiN-MgO-MA), and TiN-MgAl2O4-MnS (TiN-MA-MnS). Thermodynamic calculations suggest that single-particle TiN precipitates dominate the mushy zone of GCr15 bearing steel. Kinetic calculations regarding TiN growth suggest that the final size of the single-particle TiN ranges between 1 and 6 μm in the initial concentration range of [pct Ti] = 0.0060 to 0.0079 and [pct N] = 0.0049 to 0.0070, at 1620 to 1640 K and a local cooling rate of 0.5 to 10 K/s. The multi-particle polymerized TiN are formed by single TiN particles in three stages: single-particle TiN inclusions approach each other drawn by the cavity bridge force (CBF), local active angles consolidate, and neck region sintering occurs. Based on the thermodynamic calculations of TiN, MnS, and MgO precipitation, the formation behaviors of complex inclusions of TiN-MnS, TiN-MgO-MA, and TiN-MA-MnS were investigated.
IONIC LIQUID-CATALYZED ALKYLATION OF ISOBUTANE WITH 2-BUTENE
A detailed study of the alkylation of isobutane with 2-butene in ionic liquid media has been conducted using 1-alkyl-3-methylimidazolium halides?aluminum chloride encompassing various alkyl groups (butyl-, hexyl-, and octyl-) and halides (Cl, Br, and I) on its cations and anions,...
Perovskite Solar Cells | Photovoltaic Research | NREL
& Devices pages: High-Efficiency Crystalline PV Polycrystalline Thin-Film PV Perovskite and Organic -Defect Hybrid Organic/Inorganic Perovskite Films as PV Absorbers. (FY 2015FY 2016). In collaboration with organic metal halide perovskite (see article). Ultrahigh-Efficiency and Low-Cost Polycrystalline Halide
The Additive Coloration of Alkali Halides
ERIC Educational Resources Information Center
Jirgal, G. H.; and others
1969-01-01
Describes the construction and use of an inexpensive, vacuum furnace designed to produce F-centers in alkali halide crystals by additive coloration. The method described avoids corrosion or contamination during the coloration process. Examination of the resultant crystals is discussed and several experiments using additively colored crystals are…
Stone, Emma Louise; Wakefield, Andrew; Harris, Stephen; Jones, Gareth
2015-05-05
Artificial light at night is a major feature of anthropogenic global change and is increasingly recognized as affecting biodiversity, often negatively. On a global scale, newer technology white lights are replacing orange sodium lights to reduce energy waste. In 2009, Cornwall County Council (UK) commenced replacement of existing low-pressure sodium (LPS) high intensity discharge (HID) street lights with new Phillips CosmoPolis white ceramic metal halide street lights to reduce energy wastage. This changeover provided a unique collaborative opportunity to implement a before-after-control-impact field experiment to investigate the ecological effects of newly installed broad spectrum light technologies. Activity of the bat species Pipistrellus pipistrellus, P. pygmaeus and Nyctalus/Eptesicus spp. was significantly higher at metal halide than LPS lights, as found in other studies of bat activity at old technology (i.e. mercury vapour) white light types. No significant difference was found in feeding attempts per bat pass between light types, though more passes overall were recorded at metal halide lights. Species-specific attraction of bats to the metal halide lights could have cascading effects at lower trophic levels. We highlight the need for further research on possible ecosystem-level effects of light technologies before they are installed on a wide scale. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
Protesescu, Loredana; Yakunin, Sergii; Bodnarchuk, Maryna I; Krieg, Franziska; Caputo, Riccarda; Hendon, Christopher H; Yang, Ruo Xi; Walsh, Aron; Kovalenko, Maksym V
2015-06-10
Metal halides perovskites, such as hybrid organic-inorganic CH3NH3PbI3, are newcomer optoelectronic materials that have attracted enormous attention as solution-deposited absorbing layers in solar cells with power conversion efficiencies reaching 20%. Herein we demonstrate a new avenue for halide perovskites by designing highly luminescent perovskite-based colloidal quantum dot materials. We have synthesized monodisperse colloidal nanocubes (4-15 nm edge lengths) of fully inorganic cesium lead halide perovskites (CsPbX3, X = Cl, Br, and I or mixed halide systems Cl/Br and Br/I) using inexpensive commercial precursors. Through compositional modulations and quantum size-effects, the bandgap energies and emission spectra are readily tunable over the entire visible spectral region of 410-700 nm. The photoluminescence of CsPbX3 nanocrystals is characterized by narrow emission line-widths of 12-42 nm, wide color gamut covering up to 140% of the NTSC color standard, high quantum yields of up to 90%, and radiative lifetimes in the range of 1-29 ns. The compelling combination of enhanced optical properties and chemical robustness makes CsPbX3 nanocrystals appealing for optoelectronic applications, particularly for blue and green spectral regions (410-530 nm), where typical metal chalcogenide-based quantum dots suffer from photodegradation.
Infrared evanescent field sensing with quantum cascade lasers and planar silver halide waveguides.
Charlton, Christy; Katzir, Abraham; Mizaikoff, Boris
2005-07-15
We demonstrate the first midinfrared evanescent field absorption measurements with an InGaAs/AlInAs/InP distributed feedback (DFB) quantum cascade laser (QCL) light source operated at room temperature coupled to a free-standing, thin-film, planar, silver halide waveguide. Two different analytes, each matched to the emission frequency of a QCL, were investigated to verify the potential of this technique. The emission of a 1650 cm(-1) QCL overlaps with the amide absorption band of urea, which was deposited from methanol solution, forming urea crystals at the waveguide surface after solvent evaporation. Solid urea was detected down to 80.7 microg of precipitate at the waveguide surface. The emission frequency of a 974 cm(-1) QCL overlaps with the CH3-C absorption feature of acetic anhydride. Solutions of acetic anhydride in acetonitrile have been detected down to a volume of 0.01 microL (10.8 microg) of acetic anhydride solution after deposition at the planar waveguide (PWG) surface. Free-standing, thin-film, planar, silver halide waveguides were produced by press-tapering heated, cylindrical, silver halide fiber segments to create waveguides with a thickness of 300-190 microm, a width of 3 mm, and a length of 35 mm. In addition, Fourier transform infrared (FT-IR) evanescent field absorption measurements with planar silver halide waveguides and transmission absorption QCL measurements verify the obtained results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robinson, Sean W.; Mustoe, Chantal L.; White, Nicholas G.
The synthesis and anion binding properties of novel halogen-bonding (XB) bis-iodotriazole-pyridinium-containing acyclic and [2]catenane anion host systems are described. The XB acyclic receptor displays selectivity for acetate over halides with enhanced anion recognition properties compared to the analogous hydrogen-bonding (HB) acyclic receptor. A reversal in halide selectivity is observed in the XB [2]catenane, in comparison to the acyclic XB receptor, due to the interlocked host’s unique three-dimensional binding cavity, and no binding is observed for oxoanions. Notable halide anion association constant values determined for the [2]catenane in competitive organic–aqueous solvent mixtures demonstrate considerable enhancement of anion recognition as compared tomore » the HB catenane analogue. X-ray crystallographic analysis of a series of halide catenane complexes reveal strong XB interactions in the solid state. These interactions were studied using Cl and Br K-edge X-ray Absorption Spectroscopy (XAS) indicating intense pre-edge features characteristic of charge transfer from the halide to its bonding partner (σ AX←X–* ← X1s), and providing a direct measure of the degree of covalency in the halogen bond(s). Lastly, the data reveal that the degree of covalency is similar to that which is observed in transition metal coordinate covalent bonds. These results are supported by DFT results, which correlate well with the experimental data.« less
Watson, Kalinda; Farré, Maria José; Knight, Nicole
2015-01-01
The removal of both organic and inorganic disinfection by-product (DBP) precursors prior to disinfection is important in mitigating DBP formation, with halide removal being particularly important in salinity-impacted water sources. A matrix of waters of variable alkalinity, halide concentration and dissolved organic carbon (DOC) concentration were treated with enhanced coagulation (EC) followed by anion exchange (MIEX resin) or powdered activated carbon (PAC) and the subsequent disinfection by-product formation potentials (DBP-FPs) assessed and compared to DBP-FPs for untreated samples. Halide and DOC removal were also monitored for both treatment processes. Bromide and iodide adsorption by MIEX treatment ranged from 0 to 53% and 4-78%, respectively. As expected, EC and PAC treatments did not remove halides. DOC removal by EC/PAC was 70 ± 10%, while EC/MIEX enabled a DOC removal of 66 ± 12%. Despite the halide removals achieved by MIEX, increases in brominated disinfection by-product (Br-DBP) formation were observed relative to untreated samples, when favourable Br:DOC ratios were created by the treatment. However, the increases in formation were less than what was observed for the EC/PAC treated waters, which caused large increases in Br-DBP formation when high Br-DBP-forming water quality conditions occurred. The formation potential of fully chlorinated DBPs decreased after treatment in all cases.
Robinson, Sean W.; Mustoe, Chantal L.; White, Nicholas G.; ...
2014-12-05
The synthesis and anion binding properties of novel halogen-bonding (XB) bis-iodotriazole-pyridinium-containing acyclic and [2]catenane anion host systems are described. The XB acyclic receptor displays selectivity for acetate over halides with enhanced anion recognition properties compared to the analogous hydrogen-bonding (HB) acyclic receptor. A reversal in halide selectivity is observed in the XB [2]catenane, in comparison to the acyclic XB receptor, due to the interlocked host’s unique three-dimensional binding cavity, and no binding is observed for oxoanions. Notable halide anion association constant values determined for the [2]catenane in competitive organic–aqueous solvent mixtures demonstrate considerable enhancement of anion recognition as compared tomore » the HB catenane analogue. X-ray crystallographic analysis of a series of halide catenane complexes reveal strong XB interactions in the solid state. These interactions were studied using Cl and Br K-edge X-ray Absorption Spectroscopy (XAS) indicating intense pre-edge features characteristic of charge transfer from the halide to its bonding partner (σ AX←X–* ← X1s), and providing a direct measure of the degree of covalency in the halogen bond(s). Lastly, the data reveal that the degree of covalency is similar to that which is observed in transition metal coordinate covalent bonds. These results are supported by DFT results, which correlate well with the experimental data.« less
77 FR 32998 - Tin- and Chromium-Coated Steel Sheet From Japan
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-04
... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-860 (Second Review)] Tin- and Chromium... order on tin- and chromium-coated steel sheet from Japan would be likely to lead to continuation or... USITC Publication 4325 (May 2012), entitled Tin- and Chromium-Coated Steel Sheet from Japan...
40 CFR 471.10 - Applicability; description of the lead-tin-bismuth forming subcategory.
Code of Federal Regulations, 2014 CFR
2014-07-01
...-tin-bismuth forming subcategory. 471.10 Section 471.10 Protection of Environment ENVIRONMENTAL... METAL POWDERS POINT SOURCE CATEGORY Lead-Tin-Bismuth Forming Subcategory § 471.10 Applicability; description of the lead-tin-bismuth forming subcategory. This subpart applies to discharges of pollutants to...
26 CFR 31.3406(j)-1 - Taxpayer Identification Number (TIN) matching program.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 15 2013-04-01 2013-04-01 false Taxpayer Identification Number (TIN) matching... Number (TIN) matching program. (a) The matching program. Under section 3406(i), the Commissioner has the authority to establish Taxpayer Identification Number (TIN) matching programs. The Commissioner may...
26 CFR 31.3406(j)-1 - Taxpayer Identification Number (TIN) matching program.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 15 2011-04-01 2011-04-01 false Taxpayer Identification Number (TIN) matching... Number (TIN) matching program. (a) The matching program. Under section 3406(i), the Commissioner has the authority to establish Taxpayer Identification Number (TIN) matching programs. The Commissioner may...
26 CFR 31.3406(j)-1 - Taxpayer Identification Number (TIN) matching program.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 15 2012-04-01 2012-04-01 false Taxpayer Identification Number (TIN) matching... Number (TIN) matching program. (a) The matching program. Under section 3406(i), the Commissioner has the authority to establish Taxpayer Identification Number (TIN) matching programs. The Commissioner may...
40 CFR 471.10 - Applicability; description of the lead-tin-bismuth forming subcategory.
Code of Federal Regulations, 2012 CFR
2012-07-01
...-tin-bismuth forming subcategory. 471.10 Section 471.10 Protection of Environment ENVIRONMENTAL... METAL POWDERS POINT SOURCE CATEGORY Lead-Tin-Bismuth Forming Subcategory § 471.10 Applicability; description of the lead-tin-bismuth forming subcategory. This subpart applies to discharges of pollutants to...
40 CFR 471.10 - Applicability; description of the lead-tin-bismuth forming subcategory.
Code of Federal Regulations, 2011 CFR
2011-07-01
...-tin-bismuth forming subcategory. 471.10 Section 471.10 Protection of Environment ENVIRONMENTAL... POINT SOURCE CATEGORY Lead-Tin-Bismuth Forming Subcategory § 471.10 Applicability; description of the lead-tin-bismuth forming subcategory. This subpart applies to discharges of pollutants to waters of the...
40 CFR 471.10 - Applicability; description of the lead-tin-bismuth forming subcategory.
Code of Federal Regulations, 2013 CFR
2013-07-01
...-tin-bismuth forming subcategory. 471.10 Section 471.10 Protection of Environment ENVIRONMENTAL... METAL POWDERS POINT SOURCE CATEGORY Lead-Tin-Bismuth Forming Subcategory § 471.10 Applicability; description of the lead-tin-bismuth forming subcategory. This subpart applies to discharges of pollutants to...
40 CFR 471.10 - Applicability; description of the lead-tin-bismuth forming subcategory.
Code of Federal Regulations, 2010 CFR
2010-07-01
...-tin-bismuth forming subcategory. 471.10 Section 471.10 Protection of Environment ENVIRONMENTAL... POINT SOURCE CATEGORY Lead-Tin-Bismuth Forming Subcategory § 471.10 Applicability; description of the lead-tin-bismuth forming subcategory. This subpart applies to discharges of pollutants to waters of the...
26 CFR 31.3406(j)-1 - Taxpayer Identification Number (TIN) matching program.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 15 2014-04-01 2014-04-01 false Taxpayer Identification Number (TIN) matching... Number (TIN) matching program. (a) The matching program. Under section 3406(i), the Commissioner has the authority to establish Taxpayer Identification Number (TIN) matching programs. The Commissioner may...
26 CFR 31.3406(j)-1 - Taxpayer Identification Number (TIN) matching program.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Taxpayer Identification Number (TIN) matching... Number (TIN) matching program. (a) The matching program. Under section 3406(i), the Commissioner has the authority to establish Taxpayer Identification Number (TIN) matching programs. The Commissioner may...
NASA Technical Reports Server (NTRS)
Courey, Karim; Wright, Clara; Asfour, Shihab; Onar, Arzu; Bayliss, Jon; Ludwig, Larry
2009-01-01
In this experiment, an empirical model to quantify the probability of occurrence of an electrical short circuit from tin whiskers as a function of voltage was developed. This empirical model can be used to improve existing risk simulation models. FIB and TEM images of a tin whisker confirm the rare polycrystalline structure on one of the three whiskers studied. FIB cross-section of the card guides verified that the tin finish was bright tin.
Microwave plasma CVD of NANO structured tin/carbon composites
Marcinek, Marek [Warszawa, PL; Kostecki, Robert [Lafayette, CA
2012-07-17
A method for forming a graphitic tin-carbon composite at low temperatures is described. The method involves using microwave radiation to produce a neutral gas plasma in a reactor cell. At least one organo tin precursor material in the reactor cell forms a tin-carbon film on a supporting substrate disposed in the cell under influence of the plasma. The three dimensional carbon matrix material with embedded tin nanoparticles can be used as an electrode in lithium-ion batteries.
Preparation of textural lamellar tin deposits via electrodeposition
NASA Astrophysics Data System (ADS)
Wen, Xiaoyu; Pan, Xiaona; Wu, Libin; Li, Ruinan; Wang, Dan; Zhang, Jinqiu; Yang, Peixia
2017-06-01
Lamellar tin deposits were prepared by galvanostatical electroplating from the aqueous acidic-sulfate bath, with gelatin and benzalacetone dissolved in ethanol (ABA+EtOH) as additive, and their morphologies were investigated by scanning electron microscopy. Cathodic polarization curves revealed that the absorbability of ABA+EtOH on the cathode surface was higher than that of gelatin. X-ray diffraction analysis indicated preferred orientations of tin growth led to the formation of lamellar structure and distortion of tin lattice. The growth mechanism of lamellar tin was also discussed.
Hess, Wayne P.; Joly, Alan G.; Gerrity, Daniel P.; Beck, Kenneth M.; Sushko, Peter V.; Shlyuger, Alexander L.
2005-06-28
Energy tunable solid state sources of neutral particles are described. In a disclosed embodiment, a halogen particle source includes a solid halide sample, a photon source positioned to deliver photons to a surface of the halide, and a collimating means positioned to accept a spatially defined plume of hyperthermal halogen particles emitted from the sample surface.
10 CFR 429.54 - Metal halide lamp ballasts and fixtures.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 3 2014-01-01 2014-01-01 false Metal halide lamp ballasts and fixtures. 429.54 Section 429.54 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR... and tested to ensure that: (i) Any represented value of estimated energy efficiency calculated as the...
10 CFR 429.54 - Metal halide lamp ballasts and fixtures.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 3 2012-01-01 2012-01-01 false Metal halide lamp ballasts and fixtures. 429.54 Section 429.54 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR... and tested to ensure that: (i) Any represented value of estimated energy efficiency calculated as the...
10 CFR 429.54 - Metal halide lamp ballasts and fixtures.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 3 2013-01-01 2013-01-01 false Metal halide lamp ballasts and fixtures. 429.54 Section 429.54 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR... and tested to ensure that: (i) Any represented value of estimated energy efficiency calculated as the...
On the Boiling Points of the Alkyl Halides.
ERIC Educational Resources Information Center
Correia, John
1988-01-01
Discusses the variety of explanations in organic chemistry textbooks of a physical property of organic compounds. Focuses on those concepts explaining attractive forces between molecules. Concludes that induction interactions play a major role in alkyl halides and other polar organic molecules and should be given wider exposure in chemistry texts.…
Students' Understanding of Alkyl Halide Reactions in Undergraduate Organic Chemistry
ERIC Educational Resources Information Center
Cruz-Ramirez de Arellano, Daniel
2013-01-01
Organic chemistry is an essential subject for many undergraduate students completing degrees in science, engineering, and pre-professional programs. However, students often struggle with the concepts and skills required to successfully solve organic chemistry exercises. Since alkyl halides are traditionally the first functional group that is…
Students' Understanding of Alkyl Halide Reactions in Undergraduate Organic Chemistry
ERIC Educational Resources Information Center
Cruz-Ramírez de Arellano, Daniel; Towns, Marcy H.
2014-01-01
Organic chemistry is an essential subject for many undergraduate students completing degrees in science, engineering, and pre-professional programs. However, students often struggle with the concepts and skills required to successfully solve organic chemistry exercises. Since alkyl halides are traditionally the first functional group that is…
ERIC Educational Resources Information Center
Lash, Timothy D.; Berry, Donna
1985-01-01
Experiments involving the coupling of alkyl and aryl halides in the presence of lithium metal and ultrasound are described. The experiments illustrate classical Wurtz and Fittig reactions in addition to being a convenient application of organic sonochemistry. (JN)
Palladium-Catalyzed Conversion of Aryl and Vinyl Triflates to Bromides and Chlorides
Shen, Xiaoqiang; Hyde, Alan M.; Buchwald, Stephen L.
2010-01-01
The palladium-catalyzed conversion of aryl and vinyl triflates to aryl and vinyl halides (bromides and chlorides) has been developed using dialkylbiaryl phosphine ligands. A variety of aryl, heteroaryl and vinyl halides can be prepared via this method in good to excellent yields. PMID:20857936
NASA Astrophysics Data System (ADS)
Ganzherli, N. M.; Gulyaev, S. N.; Gurin, A. S.; Kramushchenko, D. D.; Maurer, I. A.; Chernykh, D. F.
2009-07-01
The formation of diffusers and microlens rasters on silver halide emulsions by holographic methods is considered. Two techniques for converting amplitude holographic recording to relief-phase recording, selective curing and irradiation of the emulsion gelatin by short-wavelength UV radiation, are compared.
Ab initio calculations of the lattice dynamics of silver halides
NASA Astrophysics Data System (ADS)
Gordienko, A. B.; Kravchenko, N. G.; Sedelnikov, A. N.
2010-12-01
Based on ab initio pseudopotential calculations, the results of investigations of the lattice dynamics of silver halides AgHal (Hal = Cl, Br, I) are presented. Equilibrium lattice parameters, phonon spectra, frequency densities and effective atomic-charge values are obtained for all types of crystals under study.
One-pot synthesis of magnetic silica supported copper catalyst has been described via in situ generated magnetic silica (Fe3O4@SiO2); the catalyst can be used for the efficacious amination of aryl halides in aqueous medium under microwave irradiation.
NASA GSFC Tin Whisker Homepage http://nepp.nasa.gov/whisker
NASA Technical Reports Server (NTRS)
Shaw, Harry
2000-01-01
The NASA GSFC Tin Whisker Homepage provides general information and GSFC Code 562 experimentation results regarding the well known phenomenon of tin whisker formation from pure tin plated substrates. The objective of this www site is to provide a central repository for information pertaining to this phenomenon and to provide status of the GSFC experiments to understand the behavior of tin whiskers in space environments. The Tin Whisker www site is produced by Code 562. This www site does not provide information pertaining to patented or proprietary information. All of the information contained in this www site is at the level of that produced by industry and university researchers and is published at international conferences.
Lee, Mi-Ri; Na, Seong-Hun; Park, Hwa-Sun; Suh, Su-Jeong
2014-12-01
The effect of thiourea on the electrochemical nucleation of tin on a copper substrate from a sulfate bath was studied using voltammetry, chronoamperometry, electrochemical impedance spectroscopy, and scanning electron microscopy. Without thiourea, electrodeposition of tin showed very poor surface coverage. However, re-nucleation and growth of tin occurred after the addition of thiourea. In particular, very rapid re-nucleation and growth behavior of tin were observed when up to 6 g/L of thiourea was added. Furthermore, impedance analysis allowed the estimation of the change in the growth behavior of tin when up to 6 g/L of thiourea was added.
Structural studies of supported tin catalysts
NASA Astrophysics Data System (ADS)
Nava, Noel; Viveros, Tomás
1999-11-01
Tin oxide was supported on aluminium oxide, titanium oxide, magnesium oxide and silicon oxide, and the resulting interactions between the components in the prepared samples and after reduction were characterized by Mössbauer spectroscopy. It was observed that in the oxide state, tin is present as SnO2 on alumina, magnesia and silica, but on titania tin occupies Ti sites in the structure. After hydrogen treatment at high temperatures, tin is reduced from Sn(4) to Sn(2) on alumina and titania; it is reduced from Sn(4) to Sn(0) on silica, and is practically not reduced on magnesia. These results reveal the degree of interaction between tin and the different supports studied.
Organic derivatives of tin (II/IV): Investigation of their structure
NASA Astrophysics Data System (ADS)
Szirtes, L.; Megyeri, J.; Kuzmann, E.; Beck, A.
2011-07-01
The structures of tin(II)-oxalate, tin(IV)Na-EDTA and tin(IV)Na 8-inositol hexaphosphate were investigated using XRD analysis. Samples were identified using the Mössbauer study, thermal analysis and FTIR spectrometry. The Mössbauer study determined two different oxidation states of tin atoms, and consequently two different tin surroundings in the end products. The tin oxalate was found to be orthorhombic with space group Pnma, a=9.2066(3) Å, b=9.7590(1) Å, c=13.1848(5) Å, V=1184.62 Å 3 and Z=8. SnNa-EDTA was found to be monoclinic with space group P2 1/c 1, a=10.7544(3) Å, b=10.1455(3) Å, c=16.5130(6) Å, β=98.59(2)°, V=1781.50(4) Å 3 and Z=4. Sn(C 6H 6Na 8O 24P 6) was found to be amorphous.
A charge optimized many-body potential for titanium nitride (TiN).
Cheng, Y-T; Liang, T; Martinez, J A; Phillpot, S R; Sinnott, S B
2014-07-02
This work presents a new empirical, variable charge potential for TiN systems in the charge-optimized many-body potential framework. The potential parameters were determined by fitting them to experimental data for the enthalpy of formation, lattice parameters, and elastic constants of rocksalt structured TiN. The potential does a good job of describing the fundamental physical properties (defect formation and surface energies) of TiN relative to the predictions of first-principles calculations. This potential is used in classical molecular dynamics simulations to examine the interface of fcc-Ti(0 0 1)/TiN(0 0 1) and to characterize the adsorption of oxygen atoms and molecules on the TiN(0 0 1) surface. The results indicate that the potential is well suited to model TiN thin films and to explore the chemistry associated with their oxidation.
Effect of doping of tin on optoelectronic properties of indium oxide: DFT study
NASA Astrophysics Data System (ADS)
Tripathi, Madhvendra Nath
2015-06-01
Indium tin oxide is widely used transparent conductor. Experimentally observed that 6% tin doping in indium oxide is suitable for optoelectronic applications and more doping beyond this limit degrades the optoelectronic property. The stoichiometry (In32-xSnxO48+x/2; x=0-6) is taken to understand the change in lattice parameter, electronic structure, and optical property of ITO. It is observed that lattice parameter increases and becomes constant after 6% tin doping that is in good agreement of the experimental observation. The electronic structure calculation shows that the high tin doping in indium oxide adversely affects the dispersive nature of the bottom of conduction band of pure indium oxide and decreases the carrier mobility. Optical calculations show that transmittance goes down upto 60% for the tin concentration more than 6%. The present paper shows that how more than 6% tin doping in indium oxide adversely affects the optoelectronic property of ITO.
77 FR 13156 - Carolina Power & Light Company; Shearon Harris Nuclear Power Plant, Unit 1; Exemption
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-05
... percent) and niobium (~1 percent). The elimination of tin has resulted in superior corrosion resistance and reduced irradiation-induced growth relative to both standard zircaloy (1.7 percent tin) and low-tin zircaloy (1.2 percent tin). The addition of niobium increases ductility, which is desirable to...
26 CFR 1.6050H-0 - Table of contents.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., 1989. (i) Failure to file return or to furnish statement. (ii) Failure to furnish TIN. (iii) Failure to...) Failure to furnish TIN. (iii) Failure to include correct information. (f) Requirement to request and to obtain TIN. (1) In general. (2) Manner of requesting TIN. (g) Effective date. (1) In general. (2) Points...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
78 FR 52802 - Tin T. Win, M.D., Dismissal of Proceeding
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-26
... DEPARTMENT OF JUSTICE Drug Enforcement Administration Tin T. Win, M.D., Dismissal of Proceeding On... Cause and Immediate Suspension of Registration to Tin T. Win, M.D. (hereinafter, Registrant), of Lake... order that the Order to Show Cause and Immediate Suspension of Registration issued to Tin T. Win, M.D...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-05
...) number and a Taxpayer Identification Number (TIN); b. Register both your DUNS number and TIN with the...), the Government's primary registrant database; c. Provide your DUNS number and TIN on your application... you are a corporate entity, agency, institution, or organization, you can obtain a TIN from the...
77 FR 27031 - Applications for New Awards; Centers for Independent Living
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-08
... Number (TIN); b. Register both your DUNS number and TIN with the Central Contractor Registry (CCR), the Government's primary registrant database; c. Provide your DUNS number and TIN on your application; and d..., agency, institution, or organization, you can obtain a TIN from the Internal Revenue Service. If you are...
38 CFR 61.12 - Capital grant application packages-threshold requirements.
Code of Federal Regulations, 2013 CFR
2013-07-01
... contains the Employer Identification Number or Taxpayer Identification Number (EIN/TIN) that corresponds to... must provide such an IRS determination letter, which includes their EIN/TIN. Applicants that apply under a group EIN/TIN must be identified by the parent EIN/TIN as a member or sub-unit of the parent EIN...
26 CFR 1.6050H-0 - Table of contents.
Code of Federal Regulations, 2014 CFR
2014-04-01
..., 1989. (i) Failure to file return or to furnish statement. (ii) Failure to furnish TIN. (iii) Failure to...) Failure to furnish TIN. (iii) Failure to include correct information. (f) Requirement to request and to obtain TIN. (1) In general. (2) Manner of requesting TIN. (g) Effective date. (1) In general. (2) Points...
38 CFR 61.12 - Capital grant application packages-threshold requirements.
Code of Federal Regulations, 2014 CFR
2014-07-01
... contains the Employer Identification Number or Taxpayer Identification Number (EIN/TIN) that corresponds to... must provide such an IRS determination letter, which includes their EIN/TIN. Applicants that apply under a group EIN/TIN must be identified by the parent EIN/TIN as a member or sub-unit of the parent EIN...
26 CFR 1.6050H-0 - Table of contents.
Code of Federal Regulations, 2011 CFR
2011-04-01
..., 1989. (i) Failure to file return or to furnish statement. (ii) Failure to furnish TIN. (iii) Failure to...) Failure to furnish TIN. (iii) Failure to include correct information. (f) Requirement to request and to obtain TIN. (1) In general. (2) Manner of requesting TIN. (g) Effective date. (1) In general. (2) Points...
7 CFR 3.44 - Centralized administrative offset.
Code of Federal Regulations, 2012 CFR
2012-01-01
... TINs of debtors who owe debts referred to Treasury under this section shall be compared to the names and TINs on payments to be made by Federal disbursing officials. Federal disbursing officials include... and TIN of a debtor match the name and TIN of a payee and all other requirements for offset have been...
26 CFR 1.6050H-0 - Table of contents.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., 1989. (i) Failure to file return or to furnish statement. (ii) Failure to furnish TIN. (iii) Failure to...) Failure to furnish TIN. (iii) Failure to include correct information. (f) Requirement to request and to obtain TIN. (1) In general. (2) Manner of requesting TIN. (g) Effective date. (1) In general. (2) Points...
40 CFR 721.10230 - Rutile, tin zinc, calcium doped.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Rutile, tin zinc, calcium doped. 721... Substances § 721.10230 Rutile, tin zinc, calcium doped. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as rutile, tin zinc, calcium-doped (PMN P-06...
40 CFR 721.10231 - Rutile, tin zinc, sodium-doped.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Rutile, tin zinc, sodium-doped. 721... Substances § 721.10231 Rutile, tin zinc, sodium-doped. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as rutile, tin zinc, sodium-doped (PMN P-06-37...
77 FR 34938 - Certain Tin Mill Products From Japan: Continuation of Antidumping Duty Order
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-12
... DEPARTMENT OF COMMERCE International Trade Administration [A-588-854] Certain Tin Mill Products... duty order on certain tin mill products from Japan would likely lead to continuation or recurrence of...: Background On August 28, 2000, the Department published the antidumping duty order on certain tin mill...
Code of Federal Regulations, 2012 CFR
2012-10-01
... under their ACO participant TIN as a group practice under the Physician Quality Reporting System Group... participant TIN, on behalf of its ACO supplier/provider participants who are eligible professionals, will... Physician Fee Schedule for that TIN. (4) ACO participant TINs and individual ACO providers/suppliers who are...
Code of Federal Regulations, 2013 CFR
2013-10-01
... under their ACO participant TIN as a group practice under the Physician Quality Reporting System Group... participant TIN, on behalf of its ACO supplier/provider participants who are eligible professionals, will... Physician Fee Schedule for that TIN. (4) ACO participant TINs and individual ACO providers/suppliers who are...
7 CFR 3.44 - Centralized administrative offset.
Code of Federal Regulations, 2010 CFR
2010-01-01
... TINs of debtors who owe debts referred to Treasury under this section shall be compared to the names and TINs on payments to be made by Federal disbursing officials. Federal disbursing officials include... and TIN of a debtor match the name and TIN of a payee and all other requirements for offset have been...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-18
... DEPARTMENT OF COMMERCE International Trade Administration [A-588-854] Certain Tin Mill Products... duty order covering certain tin mill products from Japan. The period of review is August 1, 2009... parties to request an administrative review of the antidumping duty order on certain tin mill products...
7 CFR 3.44 - Centralized administrative offset.
Code of Federal Regulations, 2011 CFR
2011-01-01
... TINs of debtors who owe debts referred to Treasury under this section shall be compared to the names and TINs on payments to be made by Federal disbursing officials. Federal disbursing officials include... and TIN of a debtor match the name and TIN of a payee and all other requirements for offset have been...
40 CFR 721.10231 - Rutile, tin zinc, sodium-doped.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Rutile, tin zinc, sodium-doped. 721... Substances § 721.10231 Rutile, tin zinc, sodium-doped. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as rutile, tin zinc, sodium-doped (PMN P-06-37...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-06
... DEPARTMENT OF COMMERCE International Trade Administration [A-588-854] Certain Tin Mill Products... duty order covering certain tin mill products from Japan. The period of review is August 1, 2010... parties to request an administrative review of the antidumping duty order on certain tin mill products...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
7 CFR 3.44 - Centralized administrative offset.
Code of Federal Regulations, 2013 CFR
2013-01-01
... TINs of debtors who owe debts referred to Treasury under this section shall be compared to the names and TINs on payments to be made by Federal disbursing officials. Federal disbursing officials include... and TIN of a debtor match the name and TIN of a payee and all other requirements for offset have been...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
26 CFR 1.6050H-0 - Table of contents.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., 1989. (i) Failure to file return or to furnish statement. (ii) Failure to furnish TIN. (iii) Failure to...) Failure to furnish TIN. (iii) Failure to include correct information. (f) Requirement to request and to obtain TIN. (1) In general. (2) Manner of requesting TIN. (g) Effective date. (1) In general. (2) Points...
40 CFR 721.10230 - Rutile, tin zinc, calcium doped.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Rutile, tin zinc, calcium doped. 721... Substances § 721.10230 Rutile, tin zinc, calcium doped. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as rutile, tin zinc, calcium-doped (PMN P-06...
76 FR 68512 - Carolina Power & Light Company; H. B. Robinson Steam Electric Plant, Unit 2; Exemption
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-04
... (~1 percent). The elimination of tin has resulted in superior corrosion resistance and reduced irradiation-induced growth relative to both standard zircaloy (1.7 percent tin) and low-tin zircaloy (1.2 percent tin). The addition of niobium increases ductility, which is desirable to avoid brittle failures...
7 CFR 3.44 - Centralized administrative offset.
Code of Federal Regulations, 2014 CFR
2014-01-01
... TINs of debtors who owe debts referred to Treasury under this section shall be compared to the names and TINs on payments to be made by Federal disbursing officials. Federal disbursing officials include... and TIN of a debtor match the name and TIN of a payee and all other requirements for offset have been...
Influence of Microstructure on the Electrical Properties of Heteroepitaxial TiN Films
NASA Astrophysics Data System (ADS)
Xiang, Wenfeng; Liu, Yuan; Zhang, Jiaqi
2018-05-01
Heteroepitaxial TiN films were deposited on Si substrates by pulse laser deposition at different substrate temperature. The microstructure and surface morphology of the films were investigated by X-ray diffraction (θ-2θ scan, ω-scan, and ϕ-scan) and atomic force microscopy. The electrical properties of the prepared TiN films were studied using a physical property measurement system. The experimental results showed that the crystallinity and surface morphology of the TiN films were improved gradually with increasing substrate temperature below 700 °C. Specially, single crystal TiN films were prepared when substrate temperature is above 700 °C; However, the quality of TiN films gradually worsened when the substrate temperature was increased further. The electrical properties of the films were directly correlated to their crystalline quality. At the optimal substrate temperature of 700 °C, the TiN films exhibited the lowest resistivity and highest mobility of 25.7 μΩ cm and 36.1 cm2/V s, respectively. In addition, the mechanism concerning the influence of substrate temperature on the microstructure of TiN films is discussed in detail.
NASA Astrophysics Data System (ADS)
Barraza-Lopez, Salvador; Rivero, Pablo; Yan, Jia-An; Garcia-Suarez, Victor Manuel; Ferrer, Jaime
2015-03-01
Tin fluoride has a vast literature. This material is stable in bulk form at room temperature and has commercial applications that include fluorinated toothpaste. Bulk tin fluoride has a pair of fluorine atoms bridging two tin atoms. In the recent past the electronic properties of 2D tin with honeycomb structure have been discussed thus generating a wealth of literature that emphasizes its non-topologically-trivial electronic properties due to the combination of a Dirac-like dispersion and a strong spin-orbit coupling given its large atomic mass. Nevertheless the stability of such freestanding structures has been contested recently. As it turns out, the most stable form of fluorinated tin does not possess a graphane-like structure either. In the most stable phase to be discussed here, fluorine atoms tilt away from (graphane-like) positions over/below tin atoms; in an atomistic arrangement similar to the one seen on their parent bulk structure. Electronic properties depend on atomistic coordination, and the most stable form of fluorinated tin does not possess non-trivial topological properties. Nevertheless it represents a new paradigm for valleytronics in 2D.
Organo-tins in sediments and mussels from the Sado estuarine system (Portugal).
Quevauviller, P; Lavigne, R; Pinel, R; Astruc, M
1989-01-01
Analyses of methyl- and butyl-tin levels in freshwater, estuarine and marine sediments from the Sado estuarine system, and in mussels (Mytilus galloprovincialis) from its adjacent coast, have been performed in order to detect the contaminated areas. The main inputs of tributyl-tin (TBT), along with degradation products di- and monobutyl-tin (DBT and MBT), were detected in the estuarine zone, due to high discharge from shipyards located in this area. These levels are sometimes very high, ranging from 235 to 12,200 ng g(-1) total butyl-tins in sediments. Such inputs lead to higher bioconcentration values in mussels in the estuarine zone, as well as in a harbour located along the adjacent coast. The bioconcentration of organo-tins in mussel tissues could be enhanced in estuarine turbid waters, due to an ingestion of butyl-tins adsorbed onto fine particles, in comparison with non-turbid coastal waters. Debutylation processes occur in both sediments and mussel tissues; in organisms, these processes may lead to the formation of inorganic tin, which may be methylated differently according to the period of the year.
Carbon/tin oxide composite electrodes for improved lithium-ion batteries
Li, Yunchao; Levine, Alan M.; Zhang, Jinshui; ...
2018-05-17
Tin and tin oxide-based electrodes are promising high-capacity anodes for lithium-ion batteries. However, poor capacity retention is the major issue with these materials due to the large volumetric expansion that occurs when lithium is alloyed with tin during lithiation and delithiation process. Here, a method to prepare a low-cost, scalable carbon and tin(II) oxide composite anode is reported. The composite material was prepared by ball milling of carbon recovered from used tire powders with 25 wt% tin(II) oxide to form lithium-ion battery anode. With the impact of energy from the ball milling, tin oxide powders were uniformly distributed inside themore » pores of waste-tire-derived carbon. During lithiation and delithiation, the carbon matrix can effectively absorb the volume expansion caused by tin, thereby minimizing pulverization and capacity fade of the electrodes. In conclusion, the as-synthesized anode yielded a capacity of 690 mAh g –1 after 300 cycles at a current density of 40 mA g –1 with a stable battery performance.« less
Carbon/tin oxide composite electrodes for improved lithium-ion batteries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Yunchao; Levine, Alan M.; Zhang, Jinshui
Tin and tin oxide-based electrodes are promising high-capacity anodes for lithium-ion batteries. However, poor capacity retention is the major issue with these materials due to the large volumetric expansion that occurs when lithium is alloyed with tin during lithiation and delithiation process. Here, a method to prepare a low-cost, scalable carbon and tin(II) oxide composite anode is reported. The composite material was prepared by ball milling of carbon recovered from used tire powders with 25 wt% tin(II) oxide to form lithium-ion battery anode. With the impact of energy from the ball milling, tin oxide powders were uniformly distributed inside themore » pores of waste-tire-derived carbon. During lithiation and delithiation, the carbon matrix can effectively absorb the volume expansion caused by tin, thereby minimizing pulverization and capacity fade of the electrodes. In conclusion, the as-synthesized anode yielded a capacity of 690 mAh g –1 after 300 cycles at a current density of 40 mA g –1 with a stable battery performance.« less
Pechini process-derived tin oxide and tin oxide-graphite composites for lithium-ion batteries
NASA Astrophysics Data System (ADS)
Zhang, R.; Lee, Jim Y.; Liu, Z. L.
The Pechini process [Ceram. Bull. 68 (1989) 1002] is used to obtain fine tin oxide powders that reduce the specific volume change in Li + insertion and extraction reactions. The suitability of these tin oxides as active materials for negative electrodes in lithium-ion batteries is investigated. From elemental analysis, it is found that the templating polymer network is almost completely obliterated after heating at 500 °C. The best tin oxide does not exhibit extensive crystallization of tin atoms even after 30 cycles of alloying and de-alloying reactions with Li. The structure and the specific capacity of the oxides are dependent on the heat treatment and remnants of the polymeric CH network can impose an unfavorable outcome. A capacity of 600 mAh g -1, which is unchanged for 30 cycles, can be obtained from tin oxide heat treated at 1000 °C. Composites of graphite and SnO 2 are also prepared and exhibit synergistic interactions between graphite and tin oxide which are similar to those reported previously [Electrochem. Solid State Lett. 3 (2000) 167].
Infrared Emissivity of Tin upon Release of a 25 GPa Shock into a LiF Window
DOE Office of Scientific and Technical Information (OSTI.GOV)
Turley, W. D., Holtkamp, D. B., Marshall, B. R., Stevens, G. D., Veeser, L. R.
We measured the emissivity of a tin sample at its interface with a lithium-fluoride window upon release of a 25 GPa shock wave from the tin into the window. Measurements were made over four wavelength bands between 1.2 and 5.4 μm. Thermal emission backgrounds from the tin, glue, and lithium fluoride were successfully removed from the reflectance signals. Emissivity changes for the sample, which was initially nearly specular, were small except for the longest wavelength band, where uncertainties were high because of poor signal-to-noise ratio at that wavelength. A thin glue layer, which bonds the sample to the window, wasmore » found to heat from reverberations of the shock wave between the tin and the lithium fluoride. At approximately 3.4 μm the thermal emission from the glue was large compared to the tin, allowing a good estimate of the glue temperature from the thermal radiance. The glue appears to remain slightly colder than the tin, thereby minimizing heat conduction into or out of the tin immediately after the shock passage.« less
Influence of silicon oxide on the performance of TiN bottom electrode in phase change memory
NASA Astrophysics Data System (ADS)
Gao, Dan; Liu, Bo; Xu, Zhen; Wang, Heng; Xia, Yangyang; Wang, Lei; Zhu, Nanfei; Li, Ying; Zhan, Yipeng; Song, Zhitang; Feng, Songlin
2016-10-01
The stability of TiN which is the preferred bottom electrode contact (BEC) of phase change memory (PCM) due to its low thermal conductivity and suitable electrical conductivity, is very essential to the reliability of PCM devices. In this work, in order to investigate the effect of high aspect ratio process (HARP) SiO2 on the performance of TiN, both TiN/SiO2, TiN/SiN thin films and TiN BEC device structures are analyzed. By combining transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS), we found that the TiN would be oxidized after the deposition of HARP SiO2 and there exist a thin ( 4 nm) oxidation interfacial layer between TiN and SiO2. Electrical measurements were performed on the 1R PCM test-key die with 7 nm and 10 nm BEC-only cells. The statistical initial resistances of BEC have wide distribution and it is confirmed that the non-uniform oxidation of TiN BEC affects the astringency of the resistance of TiN BEC. The experimental results help to optimize the process of TiN BEC, and SiN is recommended as a better choice as the linear layer.
Kanwar, Y S; Kumar, A; Yang, Q; Tian, Y; Wada, J; Kashihara, N; Wallner, E I
1999-09-28
Tubulointerstitial nephritis antigen (TIN-ag) is an extracellular matrix protein and is expressed in the renal tubular basement membranes. Its role in metanephric development was investigated. TIN-ag cDNA, isolated from the newborn mouse library, had an ORF of 1,425 nucleotides, a putative signal sequence, and an ATP/GTP-binding site. The translated sequence had approximately 80% identity with rabbit TIN-ag. Among various tissues, TIN-ag mRNA was primarily expressed in the newborn kidney. In the embryonic metanephros, TIN-ag expression was confined to the distal convolution or pole of the S-shaped body, the segment of the nascent nephron that is the progenitor of renal tubules. Treatment with TIN-ag antisense oligodeoxynucleotide induced dysmorphogenesis of the embryonic metanephroi, malformation of the S-shaped body, and a decrease in the tubular population, whereas the glomeruli were unaffected. Treatment also led to a decrease of TIN-Ag mRNA, de novo synthesis of TIN-ag protein, and its antibody reactivity. The mRNA expression of glomerular epithelial protein 1 (a marker for renal podocytes), anti-heparan-sulfate-proteoglycan antibody reactivity, and wheat germ agglutinin lectin staining of the metanephros were unaffected. The anti-TIN-ag antibody treatment also caused deformation of the S-shaped body and a reduction in the tubular population, whereas the glomeruli were unchanged. The data suggest that the TIN-ag, unlike other basement membrane proteins, selectively regulates tubulogenesis, whereas glomerulogenesis is largely unaffected.
NASA Astrophysics Data System (ADS)
Lee, Mun Hyung; Park, Joo Hyun
2018-06-01
The effect of nitrogen content on the formation of an equiaxed solidification structure of Fe-16Cr steel was investigated. Moreover, two different kinds of refractory materials, i.e., alumina and magnesia, were employed to control the type of oxide inclusion. The characteristics of TiN(-oxide) inclusions were quantitatively analyzed in both molten steel and solidified samples. When the melting was carried out in the alumina refractory, the grain size continuously decreased with increasing nitrogen content. However, a minimum grain size was observed at a specific nitrogen content (approx. 150 ppm) when the steel was melted in the magnesia refractory. Most of the single TiN particles had a cuboidal shape and fine irregularly shaped particles were located along the grain boundary due to the microsegregation of Ti at the grain boundary during solidification. The type of TiN-oxide hybrid inclusion was strongly affected by the refractory material where Al2O3-TiN and MgAl2O4-TiN hybrid-type inclusions were obtained in the alumina and magnesia refractory experiments, respectively. The formation of oxide inclusions was well predicted by thermochemical computations and it was commonly found that oxide particles were initially formed, followed by the nucleation and growth of TiN. When the nitrogen content increased, the number density of TiN linearly increased in the alumina refractory experiments. However, the number of TiN exhibits a maximum at about [N] = 150 ppm, at which a minimum grain size was obtained in the magnesia refractory experiments. Therefore, the larger the number density of TiN, the smaller the primary grain size after solidification. The number density of TiN in the steel melted in the magnesia refractory was greater than that in the steel melted in the alumina refractory at given Ti and N contents, which was due to the lower planar lattice disregistry of MgAl2O4-TiN interface rather than that of Al2O3-TiN interface. When Δ T TiN (= difference between the TiN precipitation temperature and the liquidus of the steel) was 20 K to 40 K, the number density of effective TiN was maximized and thus, the grain size was minimized after solidification. Finally, although most of the TiN particles were smaller than 1 μm in the molten steel samples irrespective of the nitrogen content, TiN particles larger than 10 μm were observed in the solidified samples when the nitrogen content was greater than 150 ppm. The growth of TiN particles during melting and solidification was well predicted by the combinatorial simulation of the `Ostwald ripening model' based on the Lifshitz-Slyozov-Wagner theory in conjunction with the `Diffusion controlled model' using Ohnaka's microsegregation equation.
NASA Astrophysics Data System (ADS)
Lee, Mun Hyung; Park, Joo Hyun
2018-03-01
The effect of nitrogen content on the formation of an equiaxed solidification structure of Fe-16Cr steel was investigated. Moreover, two different kinds of refractory materials, i.e., alumina and magnesia, were employed to control the type of oxide inclusion. The characteristics of TiN(-oxide) inclusions were quantitatively analyzed in both molten steel and solidified samples. When the melting was carried out in the alumina refractory, the grain size continuously decreased with increasing nitrogen content. However, a minimum grain size was observed at a specific nitrogen content (approx. 150 ppm) when the steel was melted in the magnesia refractory. Most of the single TiN particles had a cuboidal shape and fine irregularly shaped particles were located along the grain boundary due to the microsegregation of Ti at the grain boundary during solidification. The type of TiN-oxide hybrid inclusion was strongly affected by the refractory material where Al2O3-TiN and MgAl2O4-TiN hybrid-type inclusions were obtained in the alumina and magnesia refractory experiments, respectively. The formation of oxide inclusions was well predicted by thermochemical computations and it was commonly found that oxide particles were initially formed, followed by the nucleation and growth of TiN. When the nitrogen content increased, the number density of TiN linearly increased in the alumina refractory experiments. However, the number of TiN exhibits a maximum at about [N] = 150 ppm, at which a minimum grain size was obtained in the magnesia refractory experiments. Therefore, the larger the number density of TiN, the smaller the primary grain size after solidification. The number density of TiN in the steel melted in the magnesia refractory was greater than that in the steel melted in the alumina refractory at given Ti and N contents, which was due to the lower planar lattice disregistry of MgAl2O4-TiN interface rather than that of Al2O3-TiN interface. When ΔT TiN (= difference between the TiN precipitation temperature and the liquidus of the steel) was 20 K to 40 K, the number density of effective TiN was maximized and thus, the grain size was minimized after solidification. Finally, although most of the TiN particles were smaller than 1 μm in the molten steel samples irrespective of the nitrogen content, TiN particles larger than 10 μm were observed in the solidified samples when the nitrogen content was greater than 150 ppm. The growth of TiN particles during melting and solidification was well predicted by the combinatorial simulation of the `Ostwald ripening model' based on the Lifshitz-Slyozov-Wagner theory in conjunction with the `Diffusion controlled model' using Ohnaka's microsegregation equation.
Inhomogeneous degradation in metal halide perovskites
NASA Astrophysics Data System (ADS)
Yang, Rong; Zhang, Li; Cao, Yu; Miao, Yanfeng; Ke, You; Wei, Yingqiang; Guo, Qiang; Wang, Ying; Rong, Zhaohua; Wang, Nana; Li, Renzhi; Wang, Jianpu; Huang, Wei; Gao, Feng
2017-08-01
Although the rapid development of organic-inorganic metal halide perovskite solar cells has led to certified power conversion efficiencies of above 20%, their poor stability remains a major challenge, preventing their practical commercialization. In this paper, we investigate the intrinsic origin of the poor stability in perovskite solar cells by using a confocal fluorescence microscope. We find that the degradation of perovskite films starts from grain boundaries and gradually extend to the center of the grains. Firmly based on our findings, we further demonstrate that the device stability can be significantly enhanced by increasing the grain size of perovskite crystals. Our results have important implications to further enhance the stability of optoelectronic devices based on metal halide perovskites.
Development and melt growth of novel scintillating halide crystals
NASA Astrophysics Data System (ADS)
Yoshikawa, Akira; Yokota, Yuui; Shoji, Yasuhiro; Kral, Robert; Kamada, Kei; Kurosawa, Shunsuke; Ohashi, Yuji; Arakawa, Mototaka; Chani, Valery I.; Kochurikhin, Vladimir V.; Yamaji, Akihiro; Andrey, Medvedev; Nikl, Martin
2017-12-01
Melt growth of scintillating halide crystals is reviewed. The vertical Bridgman growth technique is still considered as very popular method that enables production of relatively large and commercially attractive crystals. On the other hand, the micro-pulling-down method is preferable when fabrication of small samples, sufficient for preliminary characterization of their optical and/or scintillation performance, is required. Moreover, bulk crystal growth is also available using the micro-pulling-down furnace. The examples of growths of various halide crystals by industrially friendly melt growth techniques including Czochralski and edge-defined film-fed growth methods are also discussed. Finally, traveling molten zone growth that in some degree corresponds to horizontal zone melting is briefly overviewed.
Adinolfi, Valerio; Peng, Wei; Walters, Grant; Bakr, Osman M; Sargent, Edward H
2018-01-01
Organometal halide perovskites are under intense study for use in optoelectronics. Methylammonium and formamidinium lead iodide show impressive performance as photovoltaic materials; a premise that has spurred investigations into light-emitting devices and photodetectors. Herein, the optical and electrical material properties of organometal halide perovskites are reviewed. An overview is given on how the material composition and morphology are tied to these properties, and how these properties ultimately affect device performance. Material attributes and techniques used to estimate them are analyzed for different perovskite materials, with a particular focus on the bandgap, mobility, diffusion length, carrier lifetime, and trap-state density. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Synthesis and spectral studies of platinum metal complexes of benzoin thiosemicarbazone
NASA Astrophysics Data System (ADS)
Offiong, Offiong E.
1994-11-01
The platinum metal chelates of benzoin thiosemicarbazone obtained with Ru(III), Rh(III), Ir(III), Pd(II) and Pt(II) were prepared from their corresponding halide salts. The complexes were characterized by elemental analysis, conductance measurement, IR, Raman, 1H-NMR, 13C-NMR and UV-visible spectra studies. Various ligand field parameters and nephelauxetic parameters were also calculated. The mode of bonding and the geometry of the ligand environment around the metal ion have been discussed in the light of the available data obtained. Complexes of Ru(III), Rh(III) and Ir(III) are six-coordinate octahedral, while Pd(II) and Pt(II) halide complexes are four-coordinated with halides bridging.
Alkali Halide Microstructured Optical Fiber for X-Ray Detection
NASA Technical Reports Server (NTRS)
DeHaven, S. L.; Wincheski, R. A.; Albin, S.
2014-01-01
Microstructured optical fibers containing alkali halide scintillation materials of CsI(Na), CsI(Tl), and NaI(Tl) are presented. The scintillation materials are grown inside the microstructured fibers using a modified Bridgman-Stockbarger technique. The x-ray photon counts of these fibers, with and without an aluminum film coating are compared to the output of a collimated CdTe solid state detector over an energy range from 10 to 40 keV. The photon count results show significant variations in the fiber output based on the materials. The alkali halide fiber output can exceed that of the CdTe detector, dependent upon photon counter efficiency and fiber configuration. The results and associated materials difference are discussed.
76 FR 17391 - Applications for New Awards; United States-Brazil Higher Education Consortia Program
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-29
... Number (TIN); b. Register both your DUNS number and TIN with the Central Contractor Registry (CCR), the Government's primary registrant database; c. Provide your DUNS number and TIN on your application; and d..., agency, institution, or organization, you can obtain a TIN from the Internal Revenue Service. If you are...
19 CFR 159.22 - Net weights and tares.
Code of Federal Regulations, 2013 CFR
2013-04-01
... tins imported from Spain: The following schedule drained weight shall be used as the Customs dutiable... in tins and such drained weight being the allowance made in liquidation for tare for water: Size can Drained weight 3 kilo 13.6 kilograms-case of 6 tins. 794 grams 16.7 kilograms-case of 24 tins. 425 grams 8...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-17
... (DUNS) number and a Taxpayer Identification Number (TIN); b. Register both your DUNS number and TIN with... (SAM), the Government's primary registrant database; c. Provide your DUNS number and TIN on your... you are a corporate entity, agency, institution, or organization, you can obtain a TIN from the...
76 FR 66855 - United States Savings Bonds, Series EE, HH and I
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-28
.... 351.43 to read as follows: Sec. 351.43 Are Taxpayer Identification Numbers (TINs) required for the... owner's TIN is not known, the TIN of the purchaser must be included in the registration of the bond. 0 6.... 359.28 Are Taxpayer Identification Numbers (TINs) required for the registration of definitive series I...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-20
... Number (TIN); b. Register both your DUNS number and TIN with the Central Contractor Registry (CCR), the Government's primary registrant database; c. Provide your DUNS number and TIN on your application; and d..., agency, institution, or organization, you can obtain a TIN from the Internal Revenue Service. If you are...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-27
... agency is required to furnish its Tax Identification Number (TIN) to that agency. 31 U.S.C. 3325(d... and submitted to a disbursing official, the TIN of the contractor receiving payment under the voucher... other information, its TIN. The TIN may be used by the Government to collect and report on any...
19 CFR 159.22 - Net weights and tares.
Code of Federal Regulations, 2012 CFR
2012-04-01
... tins imported from Spain: The following schedule drained weight shall be used as the Customs dutiable... in tins and such drained weight being the allowance made in liquidation for tare for water: Size can Drained weight 3 kilo 13.6 kilograms-case of 6 tins. 794 grams 16.7 kilograms-case of 24 tins. 425 grams 8...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-26
... agency is required to furnish its Tax Identification Number (TIN) to that agency. 31 U.S.C. 3325(d... and submitted to a disbursing official, the TIN of the contractor receiving payment under the voucher... other information, its TIN. The TIN may be used by the Government to collect and report on any...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-24
... full Tire Identification Number (TIN) on one sidewall but omit the partial serial number on the other....'' YTC explained its belief that the Tire Identification Number (TIN) and the partial TIN are used to... TIN is molded on the intended outboard sidewall of these tires and consumers could be directed to have...
21 CFR 184.1845 - Stannous chloride (anhydrous and dihydrated).
Code of Federal Regulations, 2014 CFR
2014-04-01
.... 7772-99-8) is the chloride salt of metallic tin. It is prepared by reacting molten tin with either chlorine or gaseous tin tetrachloride. Dihydrated stannous chloride (SnCl2·2H2O, CAS Reg. No. 10025-69-1) is the chloride salt of metallic tin that contains two molecules of water. It is prepared from...
19 CFR 159.22 - Net weights and tares.
Code of Federal Regulations, 2014 CFR
2014-04-01
... tins imported from Spain: The following schedule drained weight shall be used as the Customs dutiable... in tins and such drained weight being the allowance made in liquidation for tare for water: Size can Drained weight 3 kilo 13.6 kilograms-case of 6 tins. 794 grams 16.7 kilograms-case of 24 tins. 425 grams 8...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-20
... noncompliance is that the subject tires do not have full or partial Tire Identification Numbers (TIN) on one of their sidewalls. YTC explained that the intended outboard sidewall did have the complete TIN, but the opposite sidewall has no TIN or partial TIN. YTC stated its belief that the noncompliance is...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-21
... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-860 (Second Review)] Tin- and Chromium... Concerning the Antidumping Duty Order on Tin- and Chromium-Coated Steel Sheet From Japan AGENCY: United.... 1675(c)(5)) to determine whether revocation of the antidumping duty order on tin- and chromium-coated...
19 CFR 159.22 - Net weights and tares.
Code of Federal Regulations, 2010 CFR
2010-04-01
... tins imported from Spain: The following schedule drained weight shall be used as the Customs dutiable... in tins and such drained weight being the allowance made in liquidation for tare for water: Size can Drained weight 3 kilo 13.6 kilograms-case of 6 tins. 794 grams 16.7 kilograms-case of 24 tins. 425 grams 8...
19 CFR 159.22 - Net weights and tares.
Code of Federal Regulations, 2011 CFR
2011-04-01
... tins imported from Spain: The following schedule drained weight shall be used as the Customs dutiable... in tins and such drained weight being the allowance made in liquidation for tare for water: Size can Drained weight 3 kilo 13.6 kilograms-case of 6 tins. 794 grams 16.7 kilograms-case of 24 tins. 425 grams 8...
77 FR 42990 - Significant New Use Rules on Certain Chemical Substances
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-23
... Toxic Substances Control Act (TSCA) for the chemical substances rutile, tin zinc, calcium-doped (CAS No. 389623-01-2) and rutile, tin zinc, sodium-doped (CAS No. 389623-07-8) which were the subject of..., tin zinc, calcium-doped (PMN P-06-36; CAS No. 389623-01-2) and rutile, tin zinc, sodium-doped (PMN P...
Effect of alloying elements on the physicomechanical properties of copper and tin bronze
NASA Astrophysics Data System (ADS)
Ri, Kh.; Komkov, V. G.; Ri, E. Kh.
2014-09-01
The effect of alloying elements (Al, Si, Mn, Zn, Ni, As) on the physicomechanical properties of copper and tin bronze (6 wt % Sn) is studied. These alloying elements are found to increase the hardness and the microhardness of the structural constituents of Cu- X alloys due to hardening the α solid solution and eutectoid, and this effect of alloying elements is most effective in tin bronze. Alloyed copper and tin bronze have a lower thermal conductivity and corrosion resistance as compared to plain copper and tin bronze.
Cole, C. W. D.; Davies, J. V. S. A.; Kipling, M. D.; Ritchie, G. L.
1964-01-01
There have been no published reports of stannosis in tinners. In this paper its occurrence in hearth tinners is described. In hearth tinning molten tin is poured into heated iron hollow-ware and smoothed over the internal surface with a cork bat. Ammonium chloride powder is used as a flux. It is considered that fumes arising in the process from the reaction of the flux and the tin caused a concentration of tin compounds in the atmosphere, and this was the mechanism by which stannosis was produced. The literature on stannosis and tinning is reviewed. Images PMID:14180484
VO2 /TiN Plasmonic Thermochromic Smart Coatings for Room-Temperature Applications.
Hao, Qi; Li, Wan; Xu, Huiyan; Wang, Jiawei; Yin, Yin; Wang, Huaiyu; Ma, Libo; Ma, Fei; Jiang, Xuchuan; Schmidt, Oliver G; Chu, Paul K
2018-03-01
Vanadium dioxide/titanium nitride (VO 2 /TiN) smart coatings are prepared by hybridizing thermochromic VO 2 with plasmonic TiN nanoparticles. The VO 2 /TiN coatings can control infrared (IR) radiation dynamically in accordance with the ambient temperature and illumination intensity. It blocks IR light under strong illumination at 28 °C but is IR transparent under weak irradiation conditions or at a low temperature of 20 °C. The VO 2 /TiN coatings exhibit a good integral visible transmittance of up to 51% and excellent IR switching efficiency of 48% at 2000 nm. These unique advantages make VO 2 /TiN promising as smart energy-saving windows. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Molten tin reprocessing of spent nuclear fuel elements
Heckman, Richard A.
1983-01-01
A method and apparatus for reprocessing spent nuclear fuel is described. Within a containment vessel, a solid plug of tin and nitride precipitates supports a circulating bath of liquid tin therein. Spent nuclear fuel is immersed in the liquid tin under an atmosphere of nitrogen, resulting in the formation of nitride precipitates. The layer of liquid tin and nitride precipitates which interfaces the plug is solidified and integrated with the plug. Part of the plug is melted, removing nitride precipitates from the containment vessel, while a portion of the plug remains solidified to support the liquid tin and nitride precipitates remaining in the containment vessel. The process is practiced numerous times until substantially all of the precipitated nitrides are removed from the containment vessel.
ERIC Educational Resources Information Center
Gutow, Jonathan H.
2005-01-01
The time-resolved fluorescence experiment investigating the halide quenching of fluorescence from quinine sulfate in water is described. The objectives of the experiment include reinforcing student understanding of the kinetics of competing pathways, making connections with microscopic theories of kinetics through comparison of experimental and…
NREL Postdoc Awarded for Work on Breakthrough Solar Technology | News |
widespread, new research must further these trends. One type of materials-halide perovskites-shows promise to group of Joseph M. Luther, working to develop a better understanding of halide perovskite materials fostered," Christians said. "This fellowship gives me the freedom to interact with a wide group
Cathcart, Nicole; Frank, Andrew J; Kitaev, Vladimir
2009-12-14
We studied effects of halides on morphology of planar twinned silver nanoparticles and demonstrated application of these effects to precisely tune silver surface plasmon resonance maxima in a broad vis-NIR range using a reliable two-stage modification protocol.
10 CFR 431.325 - Units to be tested.
Code of Federal Regulations, 2011 CFR
2011-01-01
... EQUIPMENT Metal Halide Lamp Ballasts and Fixtures Test Procedures § 431.325 Units to be tested. For each basic model of metal halide lamp ballast selected for testing, a sample of sufficient size, no less than... energy efficiency calculated as the measured output power to the lamp divided by the measured input power...
36 CFR § 1254.108 - What are NARA's requirements for the microfilming process?
Code of Federal Regulations, 2013 CFR
2013-07-01
... you leave unattended. (j) We inspect the microform output at scheduled intervals during the project to... images, you must provide NARA with a silver halide duplicate negative upon completion of the project. When the project involves more than 10,000 images, you must provide a silver halide duplicate negative...
Semiempirical and DFT Investigations of the Dissociation of Alkyl Halides
ERIC Educational Resources Information Center
Waas, Jack R.
2006-01-01
Enthalpy changes corresponding to the gas phase heats of dissociation of 12 organic halides were calculated using two semiempirical methods, the Hartree-Fock method, and two DFT methods. These calculated values were compared to experimental values where possible. All five methods agreed generally with the expected empirically known trends in the…
10 CFR Appendix A to Subpart S of... - Compliance Statement for Metal Halide Lamp Ballasts
Code of Federal Regulations, 2011 CFR
2011-01-01
... Equipment: Metal Halide Lamp Ballasts Manufacturer's or Private Labeler's Name and Address: [Company name] (“the company”) submits this Compliance Statement under 10 CFR Part 431 (Energy Efficiency Program for... Reports submitted by or on behalf of this company. All information in such Certification Report(s) and in...
Method of Obtaining Uniform Coatings on Graphite
Campbell, I. E.
1961-04-01
A method is given for obtaining uniform carbide coatings on graphite bodies. According to the invention a metallic halide in vapor form is passed over the graphite body under such conditions of temperature and pressure that the halide reacts with the graphite to form a coating of the metal carbide on the surface of the graphite.
METHOD OF OBTAINING UNIFORM COATINGS ON GRAPHITE
Campbell, I.E.
1961-04-01
A method is given for obtaining uniform carbide coatings on graphite bodies. According to the invention a metallic halide in vapor form is passed over the graphite body under such conditions of temperature and pressure that the halide reacts with the graphite to form a coating of the metal carbide on the surface of the graphite.
10 CFR 431.322 - Definitions concerning metal halide lamp ballasts and fixtures.
Code of Federal Regulations, 2011 CFR
2011-01-01
... main functions. Ballast means a device used with an electric discharge lamp to obtain necessary circuit... purpose of controlling the ballast and putting the ballast in standby mode. Electronic ballast means a... instead starts lamps with high ballast open circuit voltage. Pulse-start metal halide ballast means an...
Infrared Dielectric Screening Determines the Low Exciton Binding Energy of Metal-Halide Perovskites.
Umari, Paolo; Mosconi, Edoardo; De Angelis, Filippo
2018-02-01
The performance of lead-halide perovskites in optoelectronic devices is due to a unique combination of factors, including highly efficient generation, transport, and collection of photogenerated charge carriers. The mechanism behind efficient charge generation in lead-halide perovskites is still largely unknown. Here, we investigate the factors that influence the exciton binding energy (E b ) in a series of metal-halide perovskites using accurate first-principles calculations based on solution of the Bethe-Salpeter equation, coupled to ab initio molecular dynamics simulations. We find that E b is strongly modulated by screening from low-energy phonons, which account for a factor ∼2 E b reduction, while dynamic disorder and rotational motion of the organic cations play a minor role. We calculate E b = 15 meV for MAPbI 3 , in excellent agreement with recent experimental estimates. We then explore how different material combinations (e.g., replacing Pb → Pb:Sn→ Sn; and MA → FA → Cs) may lead to different E b values and highlight the mechanisms underlying E b tuning.
Origin of Reversible Photoinduced Phase Separation in Hybrid Perovskites.
Bischak, Connor G; Hetherington, Craig L; Wu, Hao; Aloni, Shaul; Ogletree, D Frank; Limmer, David T; Ginsberg, Naomi S
2017-02-08
The distinct physical properties of hybrid organic-inorganic materials can lead to unexpected nonequilibrium phenomena that are difficult to characterize due to the broad range of length and time scales involved. For instance, mixed halide hybrid perovskites are promising materials for optoelectronics, yet bulk measurements suggest the halides reversibly phase separate upon photoexcitation. By combining nanoscale imaging and multiscale modeling, we find that the nature of halide demixing in these materials is distinct from macroscopic phase separation. We propose that the localized strain induced by a single photoexcited charge interacting with the soft, ionic lattice is sufficient to promote halide phase separation and nucleate a light-stabilized, low-bandgap, ∼8 nm iodide-rich cluster. The limited extent of this polaron is essential to promote demixing because by contrast bulk strain would simply be relaxed. Photoinduced phase separation is therefore a consequence of the unique electromechanical properties of this hybrid class of materials. Exploiting photoinduced phase separation and other nonequilibrium phenomena in hybrid materials more generally could expand applications in sensing, switching, memory, and energy storage.
Photon Transport in One-Dimensional Incommensurately Epitaxial CsPbX 3 Arrays
Wang, Yiping; Sun, Xin; Shivanna, Ravichandran; ...
2016-11-16
One-dimensional nanoscale epitaxial arrays serve as a great model in studying fundamental physics and for emerging applications. With an increasing focus laid on the Cs-based inorganic halide perovskite out of its outstanding material stability, we have applied vapor phase epitaxy to grow well aligned horizontal CsPbX 3 (X: Cl, Br, or I or their mixed) nanowire arrays in large scale on mica substrate. The as-grown nanowire features a triangular prism morphology with typical length ranging from a few tens of micrometers to a few millimeters. Structural analysis reveals that the wire arrays follow the symmetry of mica substrate through incommensuratemore » epitaxy, paving a way for a universally applicable method to grow a broad family of halide perovskite materials. We have studied the unique photon transport in the one-dimensional structure in the all-inorganic Cs-based perovskite wires via temperature dependent and spatially resolved photoluminescence. Furthermore, epitaxy of well oriented wire arrays in halide perovskite would be a promising direction for enabling the circuit-level applications of halide perovskite in high-performance electro-optics and optoelectronics.« less
Zhang, Taiyang; Dar, M. Ibrahim; Li, Ge; Xu, Feng; Guo, Nanjie; Grätzel, Michael; Zhao, Yixin
2017-01-01
Among various all-inorganic halide perovskites exhibiting better stability than organic-inorganic halide perovskites, α-CsPbI3 with the most suitable band gap for tandem solar cell application faces an issue of phase instability under ambient conditions. We discovered that a small amount of two-dimensional (2D) EDAPbI4 perovskite containing the ethylenediamine (EDA) cation stabilizes the α-CsPbI3 to avoid the undesirable formation of the nonperovskite δ phase. Moreover, not only the 2D perovskite of EDAPbI4 facilitate the formation of α-CsPbI3 perovskite films exhibiting high phase stability at room temperature for months and at 100°C for >150 hours but also the α-CsPbI3 perovskite solar cells (PSCs) display highly reproducible efficiency of 11.8%, a record for all-inorganic lead halide PSCs. Therefore, using the bication EDA presents a novel and promising strategy to design all-inorganic lead halide PSCs with high performance and reliability. PMID:28975149
Pressure-induced metallization of the halide perovskite (CH 3NH 3)PbI 3
Jaffe, Adam; Lin, Yu; Mao, Wendy L.; ...
2017-03-14
We report the metallization of the hybrid perovskite semiconductor (MA)PbI 3 (MA = CH 3NH 3 +) with no apparent structural transition. We tracked its bandgap evolution during compression in diamond-anvil cells using absorption spectroscopy and observed strong absorption over both visible and IR wavelengths at pressures above ca. 56 GPa, suggesting the imminent closure of its optical bandgap. The metallic character of (MA)PbI 3 above 60 GPa was confirmed using both IR reflectivity and variable-temperature dc conductivity measurements. The impressive semiconductor properties of halide perovskites have recently been exploited in a multitude of optoelectronic applications. Meanwhile, the study ofmore » metallic properties in oxide perovskites has revealed diverse electronic phenomena. Importantly, the mild synthetic routes to halide perovskites and the templating effects of the organic cations allow for fine structural control of the inorganic lattice. Lastly, pressure-induced closure of the 1.6 eV bandgap in (MA)PbI3 demonstrates the promise of the continued study of halide perovskites under a range of thermodynamic conditions, toward realizing wholly new electronic properties.« less
Pressure-Induced Metallization of the Halide Perovskite (CH 3 NH 3 )PbI 3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jaffe, Adam; Lin, Yu; Mao, Wendy L.
We report the metallization of the hybrid perovskite semiconductor (MA)PbI3 (MA = CH3NH3+) with no apparent structural transition. We tracked its bandgap evolution during compression in diamond-anvil cells using absorption spectroscopy and observed strong absorption over both visible and IR wavelengths at pressures above ca. 56 GPa, suggesting the imminent closure of its optical bandgap. The metallic character of (MA)PbI3 above 60 GPa was confirmed using both IR reflectivity and variable-temperature dc conductivity measurements. The impressive semiconductor properties of halide perovskites have recently been exploited in a multitude of optoelectronic applications. Meanwhile, the study of metallic properties in oxide perovskitesmore » has revealed diverse electronic phenomena. Importantly, the mild synthetic routes to halide perovskites and the templating effects of the organic cations allow for fine structural control of the inorganic lattice. Pressure-induced closure of the 1.6 eV bandgap in (MA)PbI3 demonstrates the promise of the continued study of halide perovskites under a range of thermodynamic conditions, toward realizing wholly new electronic properties.« less
Pressure-induced metallization of the halide perovskite (CH 3NH 3)PbI 3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jaffe, Adam; Lin, Yu; Mao, Wendy L.
We report the metallization of the hybrid perovskite semiconductor (MA)PbI 3 (MA = CH 3NH 3 +) with no apparent structural transition. We tracked its bandgap evolution during compression in diamond-anvil cells using absorption spectroscopy and observed strong absorption over both visible and IR wavelengths at pressures above ca. 56 GPa, suggesting the imminent closure of its optical bandgap. The metallic character of (MA)PbI 3 above 60 GPa was confirmed using both IR reflectivity and variable-temperature dc conductivity measurements. The impressive semiconductor properties of halide perovskites have recently been exploited in a multitude of optoelectronic applications. Meanwhile, the study ofmore » metallic properties in oxide perovskites has revealed diverse electronic phenomena. Importantly, the mild synthetic routes to halide perovskites and the templating effects of the organic cations allow for fine structural control of the inorganic lattice. Lastly, pressure-induced closure of the 1.6 eV bandgap in (MA)PbI3 demonstrates the promise of the continued study of halide perovskites under a range of thermodynamic conditions, toward realizing wholly new electronic properties.« less
Chen, Pei; Kuttipillai, Padmanaban S.; Wang, Lili; ...
2017-01-10
Here, we report the homoepitaxial growth of a metal halide on single crystals investigated with in situ reflection high-energy electron diffraction (RHEED) and ex situ atomic force microscopy (AFM). Epitaxial growth of NaCl on NaCl (001) is explored as a function of temperature and growth rate which provides the first detailed report of RHEED oscillations for metal halide growth. Layer-by-layer growth is observed at room temperature accompanied by clear RHEED oscillations while the growth mode transitions to an island (3D) mode at low temperature. At higher temperatures (>100 °C), RHEED oscillations and AFM data indicate a transition to a step-flowmore » growth mode. To show the importance of such metal halide growth, green organic light-emitting diodes (OLEDs) are demonstrated using a doped NaCl film with a phosphorescent emitter as the emissive layer. This study demonstrates the ability to perform in situ and non-destructive RHEED monitoring even on insulating substrates and could enable doped single crystals and crystalline substrates for a range of optoelectronic applications.« less
Banerjee, Abhinandan; Theron, Robin; Scott, Robert W J
2012-01-09
Gold and palladium nanoparticles were prepared by lithium borohydride reduction of the metal salt precursors in tetraalkylphosphonium halide ionic liquids in the absence of any organic solvents or external nanoparticle stabilizers. These colloidal suspensions remained stable and showed no nanoparticle agglomeration over many months. A combination of electrostatic interactions between the coordinatively unsaturated metal nanoparticle surface and the ionic-liquid anions, bolstered by steric protection offered by the bulky alkylated phosphonium cations, is likely to be the reason behind such stabilization. The halide anion strongly absorbs to the nanoparticle surface, leading to exceptional nanoparticle stability in halide ionic liquids; other tetraalkylphosphonium ionic liquids with non-coordinating anions, such as tosylate and hexafluorophosphate, show considerably lower affinities towards the stabilization of nanoparticles. Palladium nanoparticles stabilized in the tetraalkylphosphonium halide ionic liquid were stable, efficient, and recyclable catalysts for a variety of hydrogenation reactions at ambient pressures with sustained activity. Aerial oxidation of the metal nanoparticles occurred over time and was readily reversed by re-reduction of oxidized metal salts. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierce, R.; Peters, T.
2011-11-01
Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and the Savannah River Site (SRS) HB-Line Facility designed, developed, tested, and successfully deployed a production-scale system for the distillation of sodium chloride (NaCl) and potassium chloride (KCl) from plutonium oxide (PuO{sub 2}). Subsequent efforts adapted the vacuum salt distillation (VSD) technology for the removal of chloride and fluoride from less-volatile halide salts at the same process temperature and vacuum. Calcium chloride (CaCl{sub 2}), calcium fluoride (CaF{sub 2}), and plutonium fluoride (PuF{sub 3}) were of particular concern. To enable the use of the same operating conditions for themore » distillation process, SRNL employed in situ exchange reactions to convert the less-volatile halide salts to compounds that facilitated the distillation of halide without removal of plutonium. SRNL demonstrated the removal of halide from CaCl{sub 2}, CaF{sub 2} and PuF{sub 3} below 1000 C using VSD technology.« less
Reversible photo-induced trap formation in mixed-halide hybrid perovskites for photovoltaics.
Hoke, Eric T; Slotcavage, Daniel J; Dohner, Emma R; Bowring, Andrea R; Karunadasa, Hemamala I; McGehee, Michael D
2015-01-01
We report on reversible, light-induced transformations in (CH 3 NH 3 )Pb(Br x I 1- x ) 3 . Photoluminescence (PL) spectra of these perovskites develop a new, red-shifted peak at 1.68 eV that grows in intensity under constant, 1-sun illumination in less than a minute. This is accompanied by an increase in sub-bandgap absorption at ∼1.7 eV, indicating the formation of luminescent trap states. Light soaking causes a splitting of X-ray diffraction (XRD) peaks, suggesting segregation into two crystalline phases. Surprisingly, these photo-induced changes are fully reversible; the XRD patterns and the PL and absorption spectra revert to their initial states after the materials are left for a few minutes in the dark. We speculate that photoexcitation may cause halide segregation into iodide-rich minority and bromide-enriched majority domains, the former acting as a recombination center trap. This instability may limit achievable voltages from some mixed-halide perovskite solar cells and could have implications for the photostability of halide perovskites used in optoelectronics.
Steric engineering of metal-halide perovskites with tunable optical band gaps
NASA Astrophysics Data System (ADS)
Filip, Marina R.; Eperon, Giles E.; Snaith, Henry J.; Giustino, Feliciano
2014-12-01
Owing to their high energy-conversion efficiency and inexpensive fabrication routes, solar cells based on metal-organic halide perovskites have rapidly gained prominence as a disruptive technology. An attractive feature of perovskite absorbers is the possibility of tailoring their properties by changing the elemental composition through the chemical precursors. In this context, rational in silico design represents a powerful tool for mapping the vast materials landscape and accelerating discovery. Here we show that the optical band gap of metal-halide perovskites, a key design parameter for solar cells, strongly correlates with a simple structural feature, the largest metal-halide-metal bond angle. Using this descriptor we suggest continuous tunability of the optical gap from the mid-infrared to the visible. Precise band gap engineering is achieved by controlling the bond angles through the steric size of the molecular cation. On the basis of these design principles we predict novel low-gap perovskites for optimum photovoltaic efficiency, and we demonstrate the concept of band gap modulation by synthesising and characterising novel mixed-cation perovskites.
NASA Astrophysics Data System (ADS)
Ghosh, Pritam; Hazra, Abhijit; Ghosh, Meenakshi; Chandra Murmu, Naresh; Banerjee, Priyabrata
2018-04-01
Biologically relevant halide salts and its solution state structural properties are always been significant. In general, exposure of halide salts into polar solution medium results in solvation which in turn separates the cationic and anionic part of the salt. However, the conventional behaviour of salts might alter in presence of any secondary amine based compound, i.e.; moderately strong Lewis acid. In its consequence, to investigate the effect of secondary amine based compound in the salt solution, novel (E)-2-(4-bromobenzylidene)-1-(perfluorophenyl) hydrazine has been synthesized and used as secondary amine source. The secondary amine compound interestingly shows a drastic color change upon exposure to fluoride salts owing to hydrogen bonding interaction. Several experimental methods, e.g.; SCXRD, UV-Vis, FT-IR, ESI-MS and DLS together with modern DFT (i.e.; DFT-D3) have been performed to explore the structural properties of the halide salts upon exposure to secondary amine based compound. The effect of counter cation of the fluoride salt in binding with secondary amine source has also been investigated.
Transcending the slow bimolecular recombination in lead-halide perovskites for electroluminescence
Xing, Guichuan; Wu, Bo; Wu, Xiangyang; Li, Mingjie; Du, Bin; Wei, Qi; Guo, Jia; Yeow, Edwin K. L.; Sum, Tze Chien; Huang, Wei
2017-01-01
The slow bimolecular recombination that drives three-dimensional lead-halide perovskites' outstanding photovoltaic performance is conversely a fundamental limitation for electroluminescence. Under electroluminescence working conditions with typical charge densities lower than 1015 cm−3, defect-states trapping in three-dimensional perovskites competes effectively with the bimolecular radiative recombination. Herein, we overcome this limitation using van-der-Waals-coupled Ruddlesden-Popper perovskite multi-quantum-wells. Injected charge carriers are rapidly localized from adjacent thin few layer (n≤4) multi-quantum-wells to the thick (n≥5) multi-quantum-wells with extremely high efficiency (over 85%) through quantum coupling. Light emission originates from excitonic recombination in the thick multi-quantum-wells at much higher decay rate and efficiency than bimolecular recombination in three-dimensional perovskites. These multi-quantum-wells retain the simple solution processability and high charge carrier mobility of two-dimensional lead-halide perovskites. Importantly, these Ruddlesden-Popper perovskites offer new functionalities unavailable in single phase constituents, permitting the transcendence of the slow bimolecular recombination bottleneck in lead-halide perovskites for efficient electroluminescence. PMID:28239146
Transcending the slow bimolecular recombination in lead-halide perovskites for electroluminescence.
Xing, Guichuan; Wu, Bo; Wu, Xiangyang; Li, Mingjie; Du, Bin; Wei, Qi; Guo, Jia; Yeow, Edwin K L; Sum, Tze Chien; Huang, Wei
2017-02-27
The slow bimolecular recombination that drives three-dimensional lead-halide perovskites' outstanding photovoltaic performance is conversely a fundamental limitation for electroluminescence. Under electroluminescence working conditions with typical charge densities lower than 10 15 cm -3 , defect-states trapping in three-dimensional perovskites competes effectively with the bimolecular radiative recombination. Herein, we overcome this limitation using van-der-Waals-coupled Ruddlesden-Popper perovskite multi-quantum-wells. Injected charge carriers are rapidly localized from adjacent thin few layer (n≤4) multi-quantum-wells to the thick (n≥5) multi-quantum-wells with extremely high efficiency (over 85%) through quantum coupling. Light emission originates from excitonic recombination in the thick multi-quantum-wells at much higher decay rate and efficiency than bimolecular recombination in three-dimensional perovskites. These multi-quantum-wells retain the simple solution processability and high charge carrier mobility of two-dimensional lead-halide perovskites. Importantly, these Ruddlesden-Popper perovskites offer new functionalities unavailable in single phase constituents, permitting the transcendence of the slow bimolecular recombination bottleneck in lead-halide perovskites for efficient electroluminescence.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slavney, Adam H.; Leppert, Linn; Bartesaghi, Davide
In this study, halide double perovskites have recently been developed as less toxic analogs of the lead perovskite solar-cell absorbers APbX 3 (A = monovalent cation; X = Br or I). However, all known halide double perovskites have large bandgaps that afford weak visible-light absorption. The first halide double perovskite evaluated as an absorber, Cs 2AgBiBr 6 (1), has a bandgap of 1.95 eV. Here, we show that dilute alloying decreases 1’s bandgap by ca. 0.5 eV. Importantly, time-resolved photoconductivity measurements reveal long-lived carriers with microsecond lifetimes in the alloyed material, which is very promising for photovoltaic applications. The alloyedmore » perovskite described herein is the first double perovskite to show comparable bandgap energy and carrier lifetime to those of (CH 3NH 3)PbI 3. By describing how energy- and symmetry-matched impurity orbitals, at low concentrations, dramatically alter 1’s band edges, we open a potential pathway for the large and diverse family of halide double perovskites to compete with APbX 3 absorbers.« less
Ramkumar, Shwetha; Fan, Liang-Shih
2013-07-30
A process for producing hydrogen comprising the steps of: (i) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam, sulfur and halide contaminants in the form of H.sub.2S, COS, and HX, wherein X is a halide; (ii) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO.sub.2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO.sub.3, CaS and CaX.sub.2; (iii) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (iv) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO.sub.2, in the presence of synthesis gas, in the presence of H.sub.2 and O.sub.2, under partial vacuum, and combinations thereof.
Estimating the Probability of Electrical Short Circuits from Tin Whiskers. Part 2
NASA Technical Reports Server (NTRS)
Courey, Karim J.; Asfour, Shihab S.; Onar, Arzu; Bayliss, Jon A.; Ludwig, Larry L.; Wright, Maria C.
2010-01-01
To comply with lead-free legislation, many manufacturers have converted from tin-lead to pure tin finishes of electronic components. However, pure tin finishes have a greater propensity to grow tin whiskers than tin-lead finishes. Since tin whiskers present an electrical short circuit hazard in electronic components, simulations have been developed to quantify the risk of said short circuits occurring. Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that had an unknown probability associated with it. Note however that due to contact resistance electrical shorts may not occur at lower voltage levels. In our first article we developed an empirical probability model for tin whisker shorting. In this paper, we develop a more comprehensive empirical model using a refined experiment with a larger sample size, in which we studied the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From the resulting data we estimated the probability distribution of an electrical short, as a function of voltage. In addition, the unexpected polycrystalline structure seen in the focused ion beam (FIB) cross section in the first experiment was confirmed in this experiment using transmission electron microscopy (TEM). The FIB was also used to cross section two card guides to facilitate the measurement of the grain size of each card guide's tin plating to determine its finish .
NASA Technical Reports Server (NTRS)
Courey, Karim J.; Asfour, Shihab S.; Onar, Arzu; Bayliss, Jon A.; Ludwig, Larry L.; Wright, Maria C.
2009-01-01
To comply with lead-free legislation, many manufacturers have converted from tin-lead to pure tin finishes of electronic components. However, pure tin finishes have a greater propensity to grow tin whiskers than tin-lead finishes. Since tin whiskers present an electrical short circuit hazard in electronic components, simulations have been developed to quantify the risk of said short circuits occurring. Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that had an unknown probability associated with it. Note however that due to contact resistance electrical shorts may not occur at lower voltage levels. In our first article we developed an empirical probability model for tin whisker shorting. In this paper, we develop a more comprehensive empirical model using a refined experiment with a larger sample size, in which we studied the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From the resulting data we estimated the probability distribution of an electrical short, as a function of voltage. In addition, the unexpected polycrystalline structure seen in the focused ion beam (FIB) cross section in the first experiment was confirmed in this experiment using transmission electron microscopy (TEM). The FIB was also used to cross section two card guides to facilitate the measurement of the grain size of each card guide's tin plating to determine its finish.
Mir, Wasim J; Warankar, Avinash; Acharya, Ashutosh; Das, Shyamashis; Mandal, Pankaj; Nag, Angshuman
2017-06-01
Colloidal lead halide based perovskite nanocrystals (NCs) have been recently established as an interesting class of defect-tolerant NCs with potential for superior optoelectronic applications. The electronic band structure of thallium halides (TlX, where X = Br and I) show a strong resemblance to lead halide perovskites, where both Pb 2+ and Tl + exhibit a 6s 2 inert pair of electrons and strong spin-orbit coupling. Although the crystal structure of TlX is not perovskite, the similarities of its electronic structure with lead halide perovskites motivated us to prepare colloidal TlX NCs. These TlX NCs exhibit a wide bandgap (>2.5 eV or <500 nm) and the potential to exhibit a reduced density of deep defect states. Optical pump terahertz (THz) probe spectroscopy with excitation fluence in the range of 0.85-5.86 × 10 13 photons per cm 2 on NC films shows that the TlBr NCs possess high effective carrier mobility (∼220 to 329 cm 2 V -1 s -1 ), long diffusion length (∼0.77 to 0.98 μm), and reasonably high photoluminescence efficiency (∼10%). This combination of properties is remarkable compared to other wide-bandgap (>2.5 eV) semiconductor NCs, which suggests a reduction in the deep-defect states in the TlX NCs. Furthermore, the ultrafast carrier dynamics and temperature-dependent reversible structural phase transition together with its influence on the optical properties of the TlX NCs are studied.
Hoffman, Jacob B.; Schleper, A. Lennart; Kamat, Prashant V.
2016-06-20
All-inorganic cesium lead halide (CsPbX 3, X = Br –, I –) perovskites could potentially provide comparable photovoltaic performance with enhanced stability compared to organic–inorganic lead halide species. However, small-bandgap cubic CsPbI3 has been difficult to study due to challenges forming CsPbI 3 in the cubic phase. Here, a low-temperature procedure to form cubic CsPbI 3 has been developed through a halide exchange reaction using films of sintered CsPbBr 3 nanocrystals. The reaction was found to be strongly dependent upon temperature, featuring an Arrhenius relationship. Additionally, film thickness played a significant role in determining internal film structure at intermediate reactionmore » times. Thin films (50 nm) showed only a small distribution of CsPbBr xI 3–x species, while thicker films (350 nm) exhibited much broader distributions. Furthermore, internal film structure was ordered, featuring a compositional gradient within film. Transient absorption spectroscopy showed the influence of halide exchange on the excited state of the material. In thicker films, charge carriers were rapidly transferred to iodide-rich regions near the film surface within the first several picoseconds after excitation. Furthermore, this ultrafast vectorial charge-transfer process illustrates the potential of utilizing compositional gradients to direct charge flow in perovskite-based photovoltaics.« less
Electron detachment energies in high-symmetry alkali halide solvated-electron anions
NASA Astrophysics Data System (ADS)
Anusiewicz, Iwona; Berdys, Joanna; Simons, Jack; Skurski, Piotr
2003-07-01
We decompose the vertical electron detachment energies (VDEs) in solvated-electron clusters of alkali halides in terms of (i) an electrostatic contribution that correlates with the dipole moment (μ) of the individual alkali halide molecule and (ii) a relaxation component that is related to the polarizability (α) of the alkali halide molecule. Detailed numerical ab initio results for twelve species (MX)n- (M=Li,Na; X=F,Cl,Br; n=2,3) are used to construct an interpolation model that relates the clusters' VDEs to their μ and α values as well as a cluster size parameter r that we show is closely related to the alkali cation's ionic radius. The interpolation formula is then tested by applying it to predict the VDEs of four systems [i.e., (KF)2-, (KF)3-, (KCl)2-, and (KCl)3-] that were not used in determining the parameters of the model. The average difference between the model's predicted VDEs and the ab initio calculated electron binding energies is less than 4% (for the twelve species studied). It is concluded that one can easily estimate the VDE of a given high-symmetry solvated electron system by employing the model put forth here if the α, μ and cation ionic radii are known. Alternatively, if VDEs are measured for an alkali halide cluster and the α and μ values are known, one can estimate the r parameter, which, in turn, determines the "size" of the cluster anion.
Unraveling halide hydration: A high dilution approach.
Migliorati, Valentina; Sessa, Francesco; Aquilanti, Giuliana; D'Angelo, Paola
2014-07-28
The hydration properties of halide aqua ions have been investigated combining classical Molecular Dynamics (MD) with Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. Three halide-water interaction potentials recently developed [M. M. Reif and P. H. Hünenberger, J. Chem. Phys. 134, 144104 (2011)], along with three plausible choices for the value of the absolute hydration free energy of the proton (ΔG [minus sign in circle symbol]hyd[H+]), have been checked for their capability to properly describe the structural properties of halide aqueous solutions, by comparing the MD structural results with EXAFS experimental data. A very good agreement between theory and experiment has been obtained with one parameter set, namely LE, thus strengthening preliminary evidences for a ΔG [minus sign in circle symbol]hyd[H] value of -1100 kJ mol(-1) [M. M. Reif and P. H. Hünenberger, J. Chem. Phys. 134, 144104 (2011)]. The Cl(-), Br(-), and I(-) ions have been found to form an unstructured and disordered first hydration shell in aqueous solution, with a broad distribution of instantaneous coordination numbers. Conversely, the F(-) ion shows more ordered and defined first solvation shell, with only two statistically relevant coordination geometries (six and sevenfold complexes). Our thorough investigation on the effect of halide ions on the microscopic structure of water highlights that the perturbation induced by the Cl(-), Br(-), and I(-) ions does not extend beyond the ion first hydration shell, and the structure of water in the F(-) second shell is also substantially unaffected by the ion.
21 CFR 184.1845 - Stannous chloride (anhydrous and dihydrated).
Code of Federal Regulations, 2010 CFR
2010-04-01
.... Anhydrous stannous chloride (SnCl2, CAS Reg. No. 7772-99-8) is the chloride salt of metallic tin. It is prepared by reacting molten tin with either chlorine or gaseous tin tetrachloride. Dihydrated stannous chloride (SnCl2·2H2O, CAS Reg. No. 10025-0969-091) is the chloride salt of metallic tin that contains two...
21 CFR 189.301 - Tin-coated lead foil capsules for wine bottles.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Tin-coated lead foil capsules for wine bottles... Substances Prohibited From Indirect Addition to Human Food Through Food-Contact Surfaces § 189.301 Tin-coated lead foil capsules for wine bottles. (a) Tin-coated lead foil is composed of a lead foil coated on one...
21 CFR 189.301 - Tin-coated lead foil capsules for wine bottles.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tin-coated lead foil capsules for wine bottles. 189... Substances Prohibited From Indirect Addition to Human Food Through Food-Contact Surfaces § 189.301 Tin-coated lead foil capsules for wine bottles. (a) Tin-coated lead foil is composed of a lead foil coated on one...
21 CFR 189.301 - Tin-coated lead foil capsules for wine bottles.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Tin-coated lead foil capsules for wine bottles... Substances Prohibited From Indirect Addition to Human Food Through Food-Contact Surfaces § 189.301 Tin-coated lead foil capsules for wine bottles. (a) Tin-coated lead foil is composed of a lead foil coated on one...
Code of Federal Regulations, 2011 CFR
2011-07-01
... taxpayer identification number (TIN) when submitting a request for payment? 256.13 Section 256.13 Money and... BILLS Requesting Payments § 256.13 Are agencies required to supply a taxpayer identification number (TIN) when submitting a request for payment? Yes, agencies must include a valid TIN on all requests for...
21 CFR 184.1845 - Stannous chloride (anhydrous and dihydrated).
Code of Federal Regulations, 2013 CFR
2013-04-01
.... Anhydrous stannous chloride (SnCl2, CAS Reg. No. 7772-99-8) is the chloride salt of metallic tin. It is prepared by reacting molten tin with either chlorine or gaseous tin tetrachloride. Dihydrated stannous chloride (SnCl2·2H2O, CAS Reg. No. 10025-69-1) is the chloride salt of metallic tin that contains two...
Code of Federal Regulations, 2012 CFR
2012-07-01
... (TINs) required for registration of book-entry Series I savings bonds? 359.53 Section 359.53 Money and... Savings Bonds § 359.53 Are taxpayer identification numbers (TINs) required for registration of book-entry Series I savings bonds? The TIN of each person named in the registration is required to purchase a book...