T:Toxic;
11113-50-1Relevant articles and documents
Spielvogel, B. F.,Bratton, R. F.,Molerand, C. G.
, p. 8597 - 8598 (1972)
Architecture of lead oxide microcrystals in glass: A laser and etching based method
Almeida,Almeida,Hernandes,Mendon?a
, p. 5959 - 5964 (2016)
Lead oxide is an important glass modifier not only for affecting the chemical and mechanical stabilities of glasses, but also for improving their thermal and optical properties. Since specific properties are associated with the presence of PbO, its crystallization is important to enhance the material performance. Although considerable advances have been achieved regarding the fabrication of glass-ceramic from lead-based glasses, the spatial confinement of the crystallization remains challenging. Direct laser writing (DLW) has been considered an essential technique to overcome this issue, since material properties can be changed in localized and pre-determined regions. Although DLW with femtosecond laser pulses has been widely used for glass processing, its usage for phase transformations and control of the architecture of crystals has not been much exploited. This paper reports the design and control of β-PbO and 3PbO·H2O crystalline phases in a lead borate glass using fs-DLW followed by chemical etching at room temperature. We demonstrated that the etching in aqueous KOH solution is responsible for the glass crystallization, whereas the grooves produced by fs-laser pulses enable the selective crystallization in a pre-determined 2D pattern. The method described herein is important as it can control phase transformation at the micrometer scale and also permits the growth of lead oxide and lead oxide hydrate phases, which are not achieved by heat treatment. The morphologies of these microcrystals correspond to the structure of the respective compounds, being an octahedral euhedral crystal for 3PbO·H2O and thin sheets for β-PbO crystalline phases.
Kaczmarczyk, A.,Kolski, G. B.,Townsend, W. P.
, p. 1413 (1965)
Mongeot, H.,Tangi, A.,Bonnetot, B.
, p. 143 - 146 (1989)
Electrical and magnetic properties of nanocrystalline Fe100-xNix alloys
Vitta, Satish,Khuntia,Ravikumar,Bahadur
, p. 182 - 189 (2008)
The electrical and magnetic properties of nanocrystalline binary Fe100-xNix alloys, where x ranges from 0 to 100, prepared by a combination of aqueous and solid-state reduction processes have been studied vis-à-vis their microstructure. The microstructural studies indicate the formation of near-equilibrium phases in the alloys with crystallite size in the range 20-40 nm. The crystallite size in the case of pure Fe and Ni, however, is in the range 40-80 nm. The electrical transport in the temperature range 20-300 K exhibits a typical ferromagnetic metallic behavior in all the cases and the absolute resistivity of nanocrystalline Fe100-xNix alloys decreases monotonically with increasing Ni content. The saturation magnetization of the alloys on the other hand decreases progressively with Ni addition towards that of pure Ni value. The coercivity of alloys is found to be independent of temperature in the range 5-300 K except in the case of pure Ni wherein it increases from 30 Oe at 300 K to 65 Oe at 5 K. The electrical and magnetic properties of the nanocrystaline Fe-Ni alloys do not follow the predictions of simple itinerant band model for alloys. The temperature dependence of saturation magnetization in all the cases has a T3/2 Bloch variation while the average atomic moment of the alloys has an effective medium composition dependence.
Systematic study of Cr3+ substitution into octahedra-based microporous aluminoborates
Li, Qiaoqi,Lin, Cong,Zhou, Zhengyang,Ju, Jing,Li, Guobao,Lin, Jianhua,Gao, Wenliang,Cong, Rihong,Yang, Tao
, p. 5600 - 5608 (2014)
Single crystals of pure aluminoborate PKU-1 (Al3B 6O11(OH)5·nH2O) were obtained, and the structure was redetermined by X-ray diffraction. There are three independent Al atoms in the R3 structure model, and Al3 locates in a quite distorted octahedral environment, which was evidenced by 27Al NMR results. This distortion of Al3O6 octahedra release the strong static stress of the main framework and leads to a symmetry lowering from the previously reported R3 to the presently reported R3. We applied a pretreatment to prepare Al3+/Cr3+ aqueous solutions; as a consecquence, a very high Cr3+-to-Al3+ substitution content (50 atom %) in PKU-1 can be achieved, which is far more than enough for catalytic purposes. Additionally, the preference for Cr3+ substitution at the Al1 and Al2 sites was observed in the Rietveld refinements of the powder X-ray data of PKU-1:0.32Cr3+. We also systematically investigated the thermal behaviors of PKU-1:xCr3+ (0 ≥ x ≥ 0.50) by thermogravimetric-differential scanning calorimetry, in situ high-temperature XRD in vacuum, and postannealing experiments in furnace. The main framework of Cr3+-substituted PKU-1 could be partially retained at 1100 °C in vacuum. When 0.04 ≥ x ≥ 0.20, PKU-1:xCr3+ transferred to the PKU-5:xCr3+ (Al4B6O 15:xCr3+) structure at 750 °C by a 5 h annealing in air. Further elevating the temperature led to a decomposition into the mullite phase, Al4B2O9:xCr3+. For x > 0.20 in PKU-1:xCr3+, the heat treatment led to a composite of Cr 3+-substituted PKU-5 and Cr2O3, so the doping upper limit of Cr3+ in PKU-5 structure is around 20 atom %.
Preparation and properties of H2B2S5 and its decomposition products
Gates, Alfred S.,Edwards, Jimmie G.
, p. 2248 - 2252 (1977)
The preparation of solid H2B2S5 and its decomposition product H2S·xBS2, x = 4.84 ± 1.75, and observations of their properties by visual and chemical means and by x-ray, infrared, Raman, and mass spectrometry are reported. Metathioboric acid, (HBS2)3, was prepared by two methods and heated with sulfur in evacuated, sealed Vycor tubes to yield H2S·xBS2. Diiodotrithiadiborolane, I2B2S3, was prepared and treated with H2S to obtain H2B2S5 in benzene solution. Solid H2B2S5 decomposed and polymerized spontaneously to yield H2S·xBS2. X-ray, infrared, and Raman spectrometry revealed polymerization and extensive S-S bonding in the solid. Mass spectrometry of the vapor from the solid products gave predominantly H2B2S5+, H2S+, and their fragments at temperatures below 80°C and then high molecular weight ions up to B8S16+ at higher temperatures. Fragmentation of H2B2S5+ was shown to yield HBS3+ by identification of the corresponding metastable ion. A relationship of H2B2S5 to (BS2)n through polymerization and condensation is proposed.
Chatt,J. et al.
, p. 126 - 128 (1968)
1-(Chlorosilyl)pentaborane(9)
Geisler, Thomas C.,Norman, Arlan D.
, p. 2549 - 2550 (1972)
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Chemistry of boranes. VII. Octachlorononaborane-9 and its salts
Forstner,Haas,Muetterties
, p. 155 - 159 (1964)
Octachlorononaborane-9, B9Cl8H, is a volatile, solid pyrogenic product of H2B10Cl10·xH2O. In aqueous solution B9Cl8H is reduced to the dianion, B9Cl8H-2. Copyright 1964 by the American Chemical Society.
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McCusker,Makowski
, p. 5185,5186 (1957)
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Kelly, H. C.,Edwards, J. O.
, p. 4842 - 4846 (1960)
Keller
, p. 3078,3081, 3084, 3085 (1974)
Polarography of the tetrahydroborate ion. The effect of hydrolysis on the system
Gardiner, John A.,Collat, Justin W.
, p. 1208 - 1212 (1965)
A BH3-containing species, which is a relatively stable intermediate in the hydrolysis of sodium tetrahydroborate (NaBH4) solutions, has an important effect on the polarographic behavior of the system. Controlled potential electrolysis of solutions rich in this species has shown that it is responsible for the anodic polarographic wave at -0.64 v. vs. s.c.e. and that it is oxidized in a three-electron over-all process which yields hydrogen. The presence of an electrooxidizable hydrolysis product explains the abnormal polarographic behavior of unbuffered alkaline NaBH4 solutions and is consistent with other electrochemical studies and nuclear magnetic resonance spectroscopy of partially hydrolyzed solutions.
Reetz,T.,Katlafsky,B.
, p. 5036 - 5039 (1960)
Heal,Ramsay
, p. 950 (1974)
Brown, H. C.,Brown, C. A.
, p. 1494 - 1495 (1962)
The solid-state structure of diboronic acid, B2(OH)4
Baber, R. Angharad,Norman, Nicholas C.,Orpen, A. Guy,Rossi, Jean
, p. 773 - 775 (2003)
The crystal structure of diboronic acid contains molecules of B2(OH)4 hydrogen-bonded into two-dimensional sheets linked by B...O interactions.
Schlesinger, H. I.,Brown, H. C.,Finholt, A. E.,Gilbreath, J. R.,Hoekstra, H. R.,Hyde, E. K.
, p. 215 - 219 (1953)
DERIVES MONO ET BICYCLIQUES DU BORE TETRACOORDONNE ET DES α-AMINODIACIDES: REACTIONS AVEC DIVERS NUCLEOPHILES
Garrigues, Bernard,Mulliez, Michel
, p. 19 - 24 (1986)
Water, methanol and isopropylamine react mono- and bi-cyclic boroxazolidones (2a and 3a) by attacking the boron atom and not the CO group, with formation of aminodiacid and tricoordinated boron compounds.The boron compounds undergo successive B-C cleavage
Kinetics of Reduction of Silver(II) by Sodium Tetrahydroborate
Dasgupta, Manash,Mahanti, Mahendra K.
, p. 4133 - 4136 (1988)
The kinetics of reduction of silver(II) by sodium tetrahydroborate in aqueous acidic solution has been investigated.The reaction was observed to proceed in two steps, namely, (a) the formation of the intermediate AgI and (b) the subsequent conversion of AgI to Ag0.The activation parameters for the two steps have been separately calculated.The intermediate AgI species, and the final products, were characterized by chemical and spectral methods.A plausible mechanism for the reduction of AgII ions has been proposed.
Artsdalen, E. R. Van,Anderson, K. P.
, p. 579 - 581 (1951)
A novel profluorescent probe for detecting oxidative stress induced by metal and H2O2 in living cells
Wei, Yibin,Zhang, Yi,Liu, Zhiwei,Guo, Maolin
, p. 4472 - 4474 (2010)
A profluorescent probe that has no fluorescent response to H 2O2, iron or copper ions but can be readily activated in the presence of both H2O2 and Fe (or Cu) ion has been developed; the probe is capable of detecting oxidative stress promoted by Fe (or Cu) and H2O2 (i.e. the Fenton reaction conditions) in living cells.
Davis, R. E.,Bromels, E. B.,Kibby, C. L.
, p. 885 - 892 (1962)
Pretzer, W. R.,Rudolph, R. W.
, p. 1441 - 1447 (1976)
Acid- and Base-Catalyzed Hydrolytic Hydrogen Evolution from Diboronic Acid
Wang, Yi,Shen, Jialu,Huang, Yu,Liu, Xiang,Zhao, Qiuxia,Astruc, Didier
, p. 3013 - 3018 (2021/03/26)
The efficient production of H2 from hydrogen-rich sources, particularly from water, is a crucial task and a great challenge, both as a sustainable energy source and on the laboratory scale for hydrogenation reactions. Herein, a facile and effective synthesis of H2 and D2 from only acid- or base-catalyzed metal-free hydrolysis of B2(OH)4, a current borylation reagent, has been developed without any transition metal or ligand. Acid-catalyzed H2 evolution was completed in 4 min, whereas the base-catalyzed process needed 6 min. The large kinetic isotopic effects for this reaction with D2O, deuteration experiments and mechanistic studies have confirmed that both H atoms of H2 originate from water using either of these reactions. This new, metal-free catalytic system holds several advantages, such as high efficiency, simplicity of operation, sustainability, economy, and potential further use.
Detection of hydrogen peroxide using dioxazaborocanes: elucidation of the sensing mechanism at the molecular level by NMR and XPS measurements
Caron, Thomas,Palmas, Pascal,Frénois, Céline,Méthivier, Christophe,Pasquinet, Eric,Pradier, Claire-Marie,Serein-Spirau, Fran?oise,Hairault, Lionel,Montméat, Pierre
, p. 4114 - 4121 (2020/03/19)
A fluorescent dioxazaborocane was synthesised and characterized, in order to study its turn-off sensing process for hydrogen peroxide detection. The exposure of the dioxazaborocane to diluted vapours of H2O2 led to a strong non reversible quenching of the fluorescence. Both NMR and XPS analyses were carried out before and after exposure of dioxazaborocane to H2O2 vapours. They unequivocally show that the boron atom is oxidised in the film with cleavage of the N-B dative bond. Identification of products such as phenol and boric acid by NMR, supported by consistent XPS data, enabled the whole reaction sequence that explains the fluorescence quenching of dioxazaborocane upon H2O2 exposure to be described accurately. Direct hydrolysis of dioxazaborocane to diol, without oxidation, was only marginally observed.
