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Journal articles on the topic 'Alkali metal titanium oxides mixed'

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Published: 4 June 2021
Last updated: 2 February 2022

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1

Sakhnenko, Nykolay D., Maryna V. Ved’, and Ann V. Karakurkchi. "Effect of Doping Metals on the Structure of PEO Coatings on Titanium." International Journal of Chemical Engineering 2018 (June 19, 2018): 1–10. http://dx.doi.org/10.1155/2018/4608485.

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The structure and properties of the oxide films formed on titanium alloys by means of plasma-electrolytic oxidizing in alkali electrolytes based on pyrophosphates, borates, or acetates of alkali metals with the addition of dopants’ oxides or oxoanions of varying composition have been studied. Anodic polarization in the spark discharge (microarc) mode at application of interelectrode potential 90 to 160 V has been used to obtain mixed-oxide systems TiOx·WOy, TiOx·MoOy, TiOx·ZrO2, and TiOx·V2O5. The possibility to obtain the oxide layers containing the alloying elements by the modification of the composition of electrolytes has been stated. The chemical and phase composition as well as the topography, the microstructure, and the grain size of the formed layers depend on the applied current, interelectrode voltage, and the layer chemical composition. The effect of formed films composition on the resistance of titanium to corrosion has been discussed. Catalytic activity of mixed-oxide systems was determined in the model reaction of methyl orange dye MO photodestruction.
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2

IRICK, G., and P. N. MERCER. "ChemInform Abstract: Hydrogenations and Other Reactions on Titanium Mixed Metal Oxides." ChemInform 25, no. 18 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199418275.

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3

Rodtsevich, S. P., V. V. Tavgen’, and T. S. Minkevich. "Effect of alkali metal oxides on the properties of titanium containing glass enamels." Glass and Ceramics 64, no. 7-8 (July 2007): 244–46. http://dx.doi.org/10.1007/s10717-007-0061-0.

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4

Harada, Takuya, Cameron Halliday, Aqil Jamal, and T. Alan Hatton. "Molten ionic oxides for CO2 capture at medium to high temperatures." Journal of Materials Chemistry A 7, no. 38 (2019): 21827–34. http://dx.doi.org/10.1039/c9ta09122j.

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Molten ionic oxides based on sodium borate and mixed alkali-metal borates show remarkably fast sorption kinetics and intrinsic regenerability as liquid absorbents for CO2 capture at medium to high temperatures
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5

Zhao, Hong, Jin Hua Yao, Shu Bao Jin, and Li Jun Liang. "A New Synthetic Route to Nano Metal Oxides." Materials Science Forum 675-677 (February 2011): 223–26. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.223.

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Strong alkali anion exchange resin was employed as a hydroxyl source in the synthesis. OH- releasing rates were easily controlled by varying precursor salts, salt concentrations and temperatures, etc. The ratio between the nucleation speed and the speed of oxide crystallite growth was adjusted to favor the anisotropic growth of the crystal. Zinc and aluminum nano-sized oxide were obtained in various morphologies. X-ray diffraction (XRD), scanning electron microscope (SEM) and Energy Dispersion Spectroscopy (EDS) were employed to characterize the products. It is ascertained that the surface reaction on the resin and the mechanical grinding are the key steps in controlling the product morphology. The results show the flexibility and possibility of large scale production of various nano metal oxides and as well as mixed oxides.
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6

Sanchez-Segado, S., T. Makanyire, L. Escudero-Castejon, Y. Hara, and A. Jha. "Reclamation of reactive metal oxides from complex minerals using alkali roasting and leaching – an improved approach to process engineering." Green Chemistry 17, no. 4 (2015): 2059–80. http://dx.doi.org/10.1039/c4gc02360a.

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7

Kim, I. H., W. S. Kim, and D. S. Rhee. "Photocatalytic Activity of Fe/Ti Mixed Oxide for Degrading Humic Acid in Water." Advanced Materials Research 717 (July 2013): 95–100. http://dx.doi.org/10.4028/www.scientific.net/amr.717.95.

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The comparative experiments for removing humic acid as environmental pollutant were conducted by adsorption on iron oxide, photooxidation in the presence of titanium dioxide catalyst and combined adsorption-photooxidation by iron-titanium mixed metal oxides, where all these active components were immobilized on polypropylene granules. The main purpose of the work was the combination of adsorption and photocatalytic oxidation processes to remove humic acid. The granules with iron-titanium mixed oxide for treating humic acid gave much better results with 1.2~3 times higher removal rates comparing to the other two single coated oxides at certain pH values. And the order of removal efficiency according to pH was the same as for single iron oxide-coated granules. The ratio 1:2 of iron oxide/titanium dioxide was found optimal for maximal decolorization of humic acid solution. The total organic carbon decrease of humic acid in each experiments, when it was pre-equilibrated with mixed oxides-coated granules in the dark for 30 min and without pre-equilibration, was very similar. The results suggested that the mechanism of humic acid removal may be not only a respectively combined adsorption and photooxidation by iron oxide and titanium oxides, but an enhanced photooxidation reaction as a result of concentrating humic acid on titanium oxide surface by iron oxide.
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8

Berglund, Sean P., Son Hoang, Ryan L. Minter, Raymond R. Fullon, and C. Buddie Mullins. "Investigation of 35 Elements as Single Metal Oxides, Mixed Metal Oxides, or Dopants for Titanium Dioxide for Dye-Sensitized Solar Cells." Journal of Physical Chemistry C 117, no. 48 (November 22, 2013): 25248–58. http://dx.doi.org/10.1021/jp4073747.

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9

Wright, Christopher S., Richard I. Walton, David Thompsett, and Janet Fisher. "Investigation of Hydrothermal Routes to Mixed-Metal Cerium Titanium Oxides and Metal Oxidation State Assignment Using XANES." Inorganic Chemistry 43, no. 6 (March 2004): 2189–96. http://dx.doi.org/10.1021/ic035211u.

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10

Pacultová, K., V. Draštíková, Ž. Chromčáková, T. Bílková, K. Mamulová Kutláková, A. Kotarba, and L. Obalová. "On the stability of alkali metal promoters in Co mixed oxides during direct NO catalytic decomposition." Molecular Catalysis 428 (March 2017): 33–40. http://dx.doi.org/10.1016/j.molcata.2016.11.038.

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11

Zhao, Shunzheng, Honghong Yi, Xiaolong Tang, Shanxue Jiang, Fengyu Gao, Bowen Zhang, Yanran Zuo, and Zhixiang Wang. "The Hydrolysis of Carbonyl Sulfide at Low Temperature: A Review." Scientific World Journal 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/739501.

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Catalytic hydrolysis technology of carbonyl sulfide (COS) at low temperature was reviewed, including the development of catalysts, reaction kinetics, and reaction mechanism of COS hydrolysis. It was indicated that the catalysts are mainly involved metal oxide and activated carbon. The active ingredients which can load on COS hydrolysis catalyst include alkali metal, alkaline earth metal, transition metal oxides, rare earth metal oxides, mixed metal oxides, and nanometal oxides. The catalytic hydrolysis of COS is a first-order reaction with respect to carbonyl sulfide, while the reaction order of water changes as the reaction conditions change. The controlling steps are also different because the reaction conditions such as concentration of carbonyl sulfide, reaction temperature, water-air ratio, and reaction atmosphere are different. The hydrolysis of carbonyl sulfide is base-catalyzed reaction, and the force of the base site has an important effect on the hydrolysis of carbonyl sulfide.
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12

Bobylev, Andrey Nikolayevich, Sergey Yurievich Udovichenko, Alexander Nikolayevich Busygin, and Abdullah Haidar Ebrahim. "The Effect of Aluminum Dopant Amount in Titania Film on the Memristor Electrical Properties." Nano Hybrids and Composites 28 (February 2020): 59–64. http://dx.doi.org/10.4028/www.scientific.net/nhc.28.59.

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In a promising nanoelectronics device, namely, memristor based on metal oxides, there are many intermediate states with different conductivity between the limits of highly conductive and low-conducting states. These intermediate states can be used in the processes of associative learning of a neural network based on memristor synapses and simultaneous processing of input pulses, which consists in their weighing and summation in the neuroprocessor. By the method of simultaneous magnetron sputtering of two cathodes in a reactive oxygen environment, thin films of mixed oxides with a different mole ratio of titanium and aluminum were obtained. A method for obtaining a mixed oxide with a specified metal fractions by controlling the sputtering rates of cathodes using acoustic piezoelectric sensors is described. It is shown that the introduction of Al into titanium oxide improves the electrophysical characteristics of the memristor. The existence of an optimal fraction of Al dopant maximizing the memristor resistance ratio of the high-resistive and low-resistive states is established. The results indicate that the method of reactive magnetron deposition of mixed metal oxide by simultaneous sputtering of two cathodes provides a more uniform distribution of elements across the thickness of the active layer compared with the atomic layer deposition method. The uniform distribution is necessary to improve the stability of the memristor. It can be expected that in the memristors on mixed oxides TixSc1-xOy, HfxSc1-xOy, HfxY1-xOy, HfxLu1-xOy, ZrxSc1-xOy, ZrxY1-xOy, ZrxLu1-xOy an optimal dopant fraction corresponding to the maximally increased ratio of resistances in the high-resistance and low-resistance states will also be observed. Moreover, memristors on films with pure hafnium and zirconium oxides have a much larger range of resistive switching than titanium oxide.
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13

Wang, Xiaozhe, Zhiwu Yan, Rongrong Wang, Donghui Liu, Jianliang Zhang, and Zhengjian Liu. "Study of the enrichment characteristics of sinter by alkali metal vapors." Metallurgical Research & Technology 115, no. 3 (2018): 310. http://dx.doi.org/10.1051/metal/2018014.

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The existence forms and distributions of potassium (K) and sodium (Na) in sinter were studied by simulating the actual situations of K and Na cycle and enrichment in the blast furnace (BF). The results show that the K and Na vapor reacted with the main phase of the sinter and formed two “enrichment layers” in periphery, then the sinter samples were analyzed by means of XRD and SEM. The analysis results indicate that the main phases in light “enrichment layer” are K and Na compounds (ferrite, silicates and aluminates), iron oxide (Fe2O3) and silico-ferrite of calcium and aluminum (SFCA); while the dark “enrichment layer” mainly exists the potassium and sodium oxides. In addition, the adsorption of the sinter on K and Na vapor is the mixed adsorption of chemical and physical, and the chemical adsorption is the main adsorption method.
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14

Xiao, Zhuo Hao, An Xian Lu, and Fei Lu. "Relationship between the Thermal Expansion Coefficient and the Composition for R2O-MO-Al2O3-SiO2 System Glass." Advanced Materials Research 11-12 (February 2006): 65–68. http://dx.doi.org/10.4028/www.scientific.net/amr.11-12.65.

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The R2O-MO- Al2O3-SiO2 system glasses were prepared by conventional melt quenching technology. The composition mass fraction range of the glass is SiO2 (55%∼65%), MgO (0%∼15.2%), CaO (0%∼15.2%), SrO (0%∼15.2%), BaO (0%∼15.2%), Na2O (0%∼15.6%), K2O (0%∼15.6%). The relationship between the composition and the thermal expansion coefficient of the glass was investigated by comparing the thermal expansion coefficients of the glasses with different chemical composition. The results show that the thermal expansion coefficient of the glass increases sharply with the increase of alkali-metal oxide content and when K+, Na+ and Li+ exist simultaneously in the structure of the glass, the complex “mixed alkali effect” can be observed from the composition–thermal expansion coefficient curve. When introducing different kind but same quantity alkaline-earth metal oxide, the thermal expansion coefficient of the glasses increased obviously with the rising of the radius of alkaline-earth metal ions but the “mixed alkali effects” can also be observed for the glasses containing a few kinds of alkaline-earth metal oxides.
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15

Liu, Sha, Jianqiang Liu, Tong Wang, Chenglei Wang, Zhongwei Ge, Jie Liu, Xiaotao Hao, Na Du, and Hongdi Xiao. "Preparation and photovoltaic properties of dye-sensitized solar cells based on zinc titanium mixed metal oxides." Colloids and Surfaces A: Physicochemical and Engineering Aspects 568 (May 2019): 59–65. http://dx.doi.org/10.1016/j.colsurfa.2019.02.005.

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16

Luca, Vittorio, Galo J. A. A. Soler-Illia, Paula C. Angelomé, Paula Y. Steinberg, Elizabeth Drabarek, and Tracey L. Hanley. "Striving for order and compositional homogeneity in bulk mesoporous zirconium titanium mixed metal oxides from triblock copolymers and metal chlorides." Microporous and Mesoporous Materials 118, no. 1-3 (February 2009): 443–52. http://dx.doi.org/10.1016/j.micromeso.2008.09.037.

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17

Ishihara, A., M. Hamazaki, M. Arao, M. Matsumoto, H. Imai, Y. Kohno, K. Matsuzawa, S. Mitsushima, and K. Ota. "Titanium-Niobium Oxides Mixed with Ti4O7as Precious-Metal- and Carbon-Free Cathodes for Polymer Electrolyte Fuel Cells." Journal of The Electrochemical Society 163, no. 7 (2016): F603—F609. http://dx.doi.org/10.1149/2.0221607jes.

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18

PAN, Yan-fei, Ming FENG, Xian CUI, and Xiu-feng XU. "Catalytic activity of alkali metal doped Cu-Al mixed oxides for N2O decomposition in the presence of oxygen." Journal of Fuel Chemistry and Technology 40, no. 5 (May 2012): 601–7. http://dx.doi.org/10.1016/s1872-5813(12)60024-3.

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19

Chomiak, M., J. Trawczyński, and M. Zawadzki. "Effect of cobalt (nickel) oxide on the properties of zinc–titanium sorbents for high temperature desulphurization of model coal gas." Brazilian Journal of Chemical Engineering 38, no. 3 (July 6, 2021): 605–16. http://dx.doi.org/10.1007/s43153-021-00129-y.

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AbstractZn–Ti–Co(Ni) sorbents for H2S removal from model hot coal were prepared and characterized. Effects of cobalt (Co) and nickel (Ni) on the sorbents texture, structure, H2S sorption capacity and regeneration properties were determined. TiO2 formed mixed metal oxides with CoO and NiO in the fresh sorbents, while TiO2 and nanocrystalline sulfides of Zn, Co, Ni were found in sulphided ones. The oxidative regeneration of sulphided sorbents re-formed mixed oxides. Sorption capacity of studied materials increased along with an increase of the amount of added Co (Ni) and also with the number of work cycles. Co-doped Zn–Ti materials adsorbed up to 244% more sulfur than these of Zn–Ti, while Ni-doped materials adsorbed ca. twice more H2S than the corresponding Co-doped sorbents. The addition of Co (Ni) decreased the temperature of ZnS oxidation. The catalytic effect of the Co (Ni) oxides on the oxidation of ZnS was suggested.
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20

Amarilla, M., M. L. Veiga, C. Pico, M. Gaitan, and A. Jerez. "Synthesis and characterization of the new alkali metal germanium tellurium mixed oxides M2(GeTe)O6 (M = potassium, rubidium, cesium)." Inorganic Chemistry 28, no. 9 (May 1989): 1701–3. http://dx.doi.org/10.1021/ic00308a021.

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21

WU, Hai-peng, Wen-jing LI, Li GUO, Yan-fei PAN, and Xiu-feng XU. "Effect of promoter species and precursors on catalytic activity of alkali metal promoted NiAl mixed oxides for N2O decomposition." Journal of Fuel Chemistry and Technology 39, no. 7 (July 2011): 550–55. http://dx.doi.org/10.1016/s1872-5813(11)60034-0.

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22

Goudarzi, Mona, and Mohammad Ghorbani. "The Effect of Layer Number on the Nanostructural Ternary Mixed Oxide Containing Ti, Ru and Ir on Titanium." Advanced Materials Research 829 (November 2013): 638–42. http://dx.doi.org/10.4028/www.scientific.net/amr.829.638.

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Titanium anodes coated with noble metal oxides are widely used in chlorate industry. In fact, these anodes are dimensionally stable. In this article, the electrochemical characteristics of the ternary oxide coating created by sol-gel on titanium, which consisted of Ti, Ru and Ir, were investigated in the number of different layers. The electrochemical properties of anodes, morphology of samples, and phase analysis were investigated respectively by cyclic voltammetry and polarization measurements, Field Emission Scanning Electron Microscope (FESEM) and XRD. The result indicated that the application of the more layer number increases the rate of chlorine evolution. Also, The morphology of the coatings was cracked structures and cracks in the coating with six layers were distributed uniformly.
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23

Cao, Jiupeng, Yatong Zhu, Xiaoyu Yang, Yang Chen, Yuxiang Li, Hongdi Xiao, Wanguo Hou, and Jianqiang Liu. "The promising photo anode of graphene/zinc titanium mixed metal oxides for the CdS quantum dot-sensitized solar cell." Solar Energy Materials and Solar Cells 157 (December 2016): 814–19. http://dx.doi.org/10.1016/j.solmat.2016.08.003.

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24

Liu, Dong, Jianqiang Liu, Jie Liu, Sha Liu, Chenglei Wang, Zhongwei Ge, Xiaotao Hao, Na Du, and Hongdi Xiao. "The photovoltaic performance of CdS/CdSe quantum dots co-sensitized solar cells based on zinc titanium mixed metal oxides." Physica E: Low-dimensional Systems and Nanostructures 115 (January 2020): 113669. http://dx.doi.org/10.1016/j.physe.2019.113669.

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25

Liu, Jie, Chenglei Wang, Zhongwei Ge, Tong Wang, Lixin Xia, Yunhu Wu, Na Du, Hongdi Xiao, and Jianqiang Liu. "Investigation of the CdS quantum dot sensitized solar cells based on a series of zinc titanium mixed metal oxides." Optical Materials 107 (September 2020): 110059. http://dx.doi.org/10.1016/j.optmat.2020.110059.

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26

Hlavatý, Jaromír, and Jiří Volke. "Electrochemical Properties of Electrode Coatings Containing Highly Oxidatively Active Platinum Oxides." Collection of Czechoslovak Chemical Communications 57, no. 3 (1992): 429–38. http://dx.doi.org/10.1135/cccc19920429.

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By time-programmed anodic and cathodic polarization (galvanostatic conditions and undivided cell) chemically stable coatings of hydrated higher valency platinum oxides were deposited from a 10% aqueous solution of alkali hydroxide saturated with PtO2 on platinum, nickel, titanium, iron and glassy-carbon electrode supports. Their voltammograms yield anodic and cathodic peaks over the whole pH region (0.15 to 13.20). The peaks corresponding to the transformation of higher valency platinum oxides are developed at more positive values (cathodic peaks between +0.57 and -0.35 V, and anodic peaks from +0.88 to -0.23 V vs SCE). The peaks corresponding to the transformations of PtO2 are located in a more negative region. Upon adding toluene or its derivatives their electrocatalytic oxidation over the whole pH region is intensified by increasing the temperature to 80 °C. The preparative coatings of hydrated platinum oxides prepared by the same technique on platinum grids were only deposited on a part of the electrode surface. The preparative electrolytic oxidation of toluene on these coatings leads only to low material yields: in 0.5 M H2SO4 it gives 4% benzaldehyde and in 0.25 M NaOH even less, i.e. 3%. The linear dependence of the increase of peak currents in voltammograms of coatings plotted as a function of the cathodic polarization potential (applied in the preceding preparation in strongly acidic media) points to a liberation of alkali metal cations intercalated in the coating of hydrated higher valency platinum oxides during their deposition.
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27

Howell, Robert J., Luke A. Benson Marshall, Martin Jackson, and Brad P. Wynne. "A Method for the Production of Titanium-Tantalum Binary Alloys Using the Metalysis-FFC Process." MATEC Web of Conferences 321 (2020): 07012. http://dx.doi.org/10.1051/matecconf/202032107012.

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Titanium-tantalum alloys have historically been difficult to produce using conventional techniques due to the large difference in melting point and poor interdiffusivity rates of the two elements, leading to large levels of segregation. In this work we have investigated using the Metalysis-FFC process to overcome this problem. The Metalysis-FFC process is an electrochemical process where metal oxides are reduced by acting as a cathode in an electrolytic cell combined typically with a graphite anode and molten calcium chloride electrolyte. Previous work has proven that the process works when applied to mixed oxides to produce alloys. The reduction process is performed in the solid state and so negates the problems associated with traditional melting practices such as segregation and evaporation losses. In this work we have been able to successfully produce a range of Ti-Ta alloy powders from pure titanium to pure tantalum in 10 wt% increments using the Metalysis-FFC process. Moreover, energy dispersive spectroscopy analysis of the powders suggests uniform distribution of titanium and tantalum within all compositional ranges, suggesting the Metalysis-FFC process has the potential to be a transformative manufacturing methodology for producing titanium-tantalum alloys.
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28

Cao, Xiaozhou, Qiuyue Li, Yuanyuan Shi, Dong Wu, and Xiangxin Xue. "Preparation of V–4Cr–4Ti Alloys from Mixed Oxides via Electro-Deoxidation Process in Molten Salt." Metals 10, no. 8 (August 7, 2020): 1067. http://dx.doi.org/10.3390/met10081067.

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V–4Cr–4Ti alloys exhibit important advantages as a candidate structural materials for fusion reactor first-walls and blanket applications. V–4Cr–4Ti alloys were prepared by direct electrochemical reduction of the solid mixture of V2O3, Cr2O3 and TiO2 in the molten CaCl2–NaCl eutectic at 1073 K. The influence of cell voltage, sintering temperature and electrolysis time on the electrolysis process are reported. The microstructure and phase compositions of the products were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) during the electrolysis process. The results showed that V–4Cr–4Ti alloys can be obtained at the voltage of 3.1 V and the time of 0.5 h. Cr2O3 was first reduced to Cr metal, while V2O3 and TiO2 was reduced to low-valence oxide of vanadium and titanium. The reduction rate increases with increasing cell voltage, with much perovskite oxide formed during the electrolysis process.
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29

Yan, Qinghua, Yu Nie, Ruoyan Yang, Yuhan Cui, Dermot O’Hare, and Qiang Wang. "Highly dispersed Cu y AlO x mixed oxides as superior low-temperature alkali metal and SO 2 resistant NH 3 -SCR catalysts." Applied Catalysis A: General 538 (May 2017): 37–50. http://dx.doi.org/10.1016/j.apcata.2017.03.021.

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30

Zhao, Lizheng, Yanfei Du, Yusen Zeng, Zhizhong Kang, and Baomin Sun. "Sulfur Conversion of Mixed Coal and Gangue during Combustion in a CFB Boiler." Energies 13, no. 3 (January 23, 2020): 553. http://dx.doi.org/10.3390/en13030553.

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The construction of a power plant using a 660 MWe supercritical circulating fluidized bed (CFB) boiler with co-combustion of coal and gangue has been proposed in China. Therefore, this study simulated the distribution law and transformation mechanism of sulfur-containing phases using three low-calorific samples of gangue and coal mixtures under different conditions, based on the thermodynamic simulation software HSC Chemistry. The results showed that sulfur low in calorific value coal is mainly converted into gas phase SO2, solid phase alkali metal sulfate (Na2SO4 and K2SO4), and alkaline earth metal sulfate (CaSO4 and MgSO4) in an oxidizing atmosphere. Under a reductive atmosphere, sulfur in coal is mainly converted into gaseous H2S, COS (Carbon oxysulfide), and solid FeSx. With an increase in the O/C ratio, the distribution curve of sulfur-containing substances contracted to lower temperatures. It was established that the sulfur fixation capacity of coal ash depends on the relative amounts of basic oxides and sulfur present in it. Relevant conclusions were also verified and compared to those of the laboratory small-fluidized bed test bench and the 3 MWth CFB combustion test bench.
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31

Jirátová, Květa, Kateřina Pacultová, Jana Balabánová, Kateřina Karásková, Anna Klegová, Tereza Bílková, Věra Jandová, et al. "Precipitated K-Promoted Co–Mn–Al Mixed Oxides for Direct NO Decomposition: Preparation and Properties." Catalysts 9, no. 7 (July 9, 2019): 592. http://dx.doi.org/10.3390/catal9070592.

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Direct decomposition of nitric oxide (NO) proceeds over Co–Mn–Al mixed oxides promoted by potassium. In this study, answers to the following questions have been searched: Do the properties of the K-promoted Co–Mn–Al catalysts prepared by different methods differ from each other? The K-precipitated Co–Mn–Al oxide catalysts were prepared by the precipitation of metal nitrates with a solution of K2CO3/KOH, followed by the washing of the precipitate to different degrees of residual K amounts, and by cthe alcination of the precursors at 500 °C. The properties of the prepared catalysts were compared with those of the best catalyst prepared by the K-impregnation of a wet cake of Co–Mn–Al oxide precursors. The solids were characterized by chemical analysis, DTG, XRD, N2 physisorption, FTIR, temperature programmed reduction (H2-TPR), temperature programmed CO2 desorption (CO2-TPD), X-ray photoelectron spectrometry (XPS), and the species-resolved thermal alkali desorption method (SR-TAD). The washing of the K-precipitated cake resulted in decreasing the K amount in the solid, which affected the basicity, reducibility, and non-linearly catalytic activity in NO decomposition. The highest activity was found at ca 8 wt.% of K, while that of the best K-impregnated wet cake catalyst was at about 2 wt.% of K. The optimization of the cake washing conditions led to a higher catalytic activity.
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32

Imoisili, Patrick Ehi, Tien-Chien Jen, and Babak Safaei. "Microwave-assisted sol–gel synthesis of TiO2-mixed metal oxide nanocatalyst for degradation of organic pollutant." Nanotechnology Reviews 10, no. 1 (January 1, 2021): 126–36. http://dx.doi.org/10.1515/ntrev-2021-0016.

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Abstract Titanium dioxide (TiO2) is the most effective photocatalysts for low-cost degradation of organic pollutant; however, the wide band gap and the high recombination rate of the charge carriers are drawbacks that hinders it practical application. In this study, TiO2 and titanium mixed metal oxides ternary (V/Ag/TiO2) nanocatalyst was synthesized through a microwave-assisted sol–gel route using Ti(C4H9O)4, NH4VO3, and AgNO3 as precursors. The XRD analysis of the synthesized TiO2 and V/Ag/TiO2 depicts lattice fringes for rutile and anatase crystalline phases. Raman spectra indicate the formation of a mesoporous multiphase sample mixture of rutile and anatase phases. The spectrum shift to the visible light region was demonstrated by the UV-visible spectroscopy analysis. Diffuse reflectance spectroscopy (DRS) reveals a reduced band gap of 2.9 eV for TiO2 and 2.65 eV for V/Ag/TiO2. Brunauer–Emmett–Teller (BET) indicates a large surface area of 92.8 and 84.8 m2 g−1 for TiO2 and V/Ag/TiO2, respectively. Nitrogen adsorption–desorption isotherm exhibits type IV isotherm, signifying the presence of the mesoporous structure. SEM portrays a cluster of rod-like aggregate particles, while the HRTEM analysis illustrates nanoparticles of rod-like cylindrical shape with a homogeneous size diameter. The synthesized nanocatalyst demonstrated a significant photocatalytic ability in the degradation of methyl orange (MO) and methylene blue (MB). V/Ag/TiO2 shows higher activity in the visible region. Thus, the present report suggests efficient, suitable, and economical microwave-assisted sol–gel techniques to yield V/Ag/TiO2 nanocatalysts with harnessed photocatalytic performance for the degradation of toxic organic pollutants in the presence of visible light irradiation.
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33

Koverzin, A. M., V. G. Schipizyn, A. V. Vaschenko, A. S. Bliznyukov, M. R. Sadradinov, A. R. Makavetskas, and Yu A. Fischenko. "Study of scull and lining in the hearth of blast furnace No. 2 of JSC EVRAZ ZSMK (Report 1)." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information, no. 8 (September 1, 2018): 17–29. http://dx.doi.org/10.32339/0135-5910-2018-8-17-29.

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Results of study of lining and scull of the hearth of blast furnace No. 2 of JSC EVEAZ ZSMK presented, done after BF stop for major overhaul. It was determined, that the scull has a zonal structure, due to different conditions of the forming of it during the furnace running and blowing-down. The scull consists of isolations of graphite, metal and slag inclusions having distinctly lamellar structure. Number of slag inclusions in the scull of the hearth walls lower the hot metal tap hole is not big and sharply arises in samples at levels above the tap hole. In metal structure within the scull ferrite (a-Fe) prevails, also there are some lamellar graphite isolations and perlite. Quantity and thickness of metal isolations in the samples increases from the scull periphery to the center of blast furnace (from 20–30% and tens of microns to 70–90% (mass) and 30–50 microns correspondently) and decreases from the lower part of the hearth wall to the upper one. Titanium nitride (osbornite) TiN and titanium oxide (rutile) TiO2, sulfides of calcium, iron, manganese, silicon carbide SiC present in the scull in a small quantity (less 2%). In samples taken higher the hot metal tap hole, in the scull slag isolations there are a considerable amount of alkali metals oxides and sulfides, and phosphide and iron sulfides were exhibited in the metal phase. It speaks about considerable evaporation/sublimation of compositions of potassium, sodium, Sulphur and phosphorus in the blast furnace hearth following by their condensation/crystallization at the cooled lining of hearth walls.
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34

Ivetić, Tamara, Nina Finčur, Daniela Šojić Merkulov, Vesna Despotović, Dragana Četojević-Simin, Sanja Armaković, Maria Uzelac, et al. "Water-Active Titanium/Molybdenum/Mixed-Oxides: Removal Efficiency of Organic Water Pollutants by Adsorption and Photocatalysis and Toxicity Assessment." Catalysts 11, no. 9 (August 31, 2021): 1054. http://dx.doi.org/10.3390/catal11091054.

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A new titanium/molybdenum/mixed-oxides (TMO) contact-type heterojunction photocatalyst was prepared by a simple, low-cost, and environmentally-friendly mixing-calcination solid-state method. A microstructural investigation by scanning electron microscopy (SEM) showsirregularly shaped agglomerated morphology of TMO that consists of firmly connected globular TiO2 and rod-like MoO3 particles. The detailed structure and optical bandgap investigation by X-ray diffraction, Raman, and UV-Vis spectroscopy revealed the TMO’s composition of ~37 wt.% rutile TiO2, ~25 wt.% of anatase TiO2, and ~38 wt.% of molybdite MoO3 phase and an absorption threshold of around 380 nm, which implies more probability of desirable higher visible light absorption. The removal efficiency of pesticides quinmerac (QUI) and tembotrione (TEM), and pharmaceuticals metoprolol (MET), amitriptyline (AMI), ciprofloxacin (CIP),and ceftriaxone (CEF) from water in the presence of starting pure TiO2, MoO3, and prepared TMO were investigated under different pH values and UV irradiation/simulated sunlight (SS). Each starting metal-oxide precursors and prepared TMO showed a different affinity for adsorption of tested pesticides and pharmaceuticals, and, in general, better photocatalytic degradation efficiency under UV irradiation than under simulated sunlight. The highest photocatalytic degradation efficiency under UV irradiation was 81.6% for TEM using TMO; using TiO2 was 65.0% for AMI, and using MoO3 was 79.3% for CEF after 135 min. However, TMO showed a very high synergic adsorption/photocatalytic under-SS efficiency in the removal of CIP of almost 80% and under UV irradiation of 90% CIP removal after 75 min. The toxicity of catalysts, starting compounds, and their intermediates formed during the removal process was assessed using a rat hepatoma cell line (H-4-II-E). The highest hepatotoxic effects were obtained by using UV irradiated QUI and MET suspension with TMO for up to 60 min.
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35

Liu, Dong, Jianqiang Liu, Jie Liu, Sha Liu, Chenglei Wang, Zhongwei Ge, Xiaotao Hao, Na Du, and Hongdi Xiao. "The effect of CuS counter electrodes for the CdS/CdSe quantum dot co-sensitized solar cells based on zinc titanium mixed metal oxides." Journal of Materials Science 54, no. 6 (December 4, 2018): 4884–92. http://dx.doi.org/10.1007/s10853-018-03203-y.

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36

Liu, Jie, Jianqiang Liu, Chenglei Wang, Zhongwei Ge, Dali Wang, Lixin Xia, Liang Guo, Na Du, Xiaotao Hao, and Hongdi Xiao. "A novel ZnS/SiO2 double passivation layers for the CdS/CdSe quantum dots co-sensitized solar cells based on zinc titanium mixed metal oxides." Solar Energy Materials and Solar Cells 208 (May 2020): 110380. http://dx.doi.org/10.1016/j.solmat.2019.110380.

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37

Bykanova, V. V., V. A. Panasenko, and S. M. Bykanov. "SYNTHESIS AND PHOTOCATALYTIC ACTIVITY OF COATINGS TI/TINOM∙ZrO2 FOR PURIFICATION OF INDUSTRIAL WASTE WATER FROM ORGANIC AROMATIC CONTAMINANTS." Journal of Coal Chemistry 2 (2021): 33–40. http://dx.doi.org/10.31081/1681-309x-2021-0-2-33-40.

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It is shown that photocatalytic processes on semiconductor materials are promising for use in technologies for purifying industrial waste water and air from toxic organic impurities for solving important environmental problems. Studies on the formation of coatings with titanium(IV) oxide supplemented with zirconium(IV) oxide have been carried out. The Ti/TiO2 coverings were formed by anodic oxidation of technical alloys of VT1-0 grade titanium and E-125 zirconium from aqueous electrolyte solutions based on 0.5 M sulfuric acid and 1 M potassium pyrophosphate. To obtain mixed oxide coatings of the Ti/TinOm·ZrO2 composition, zirconium(IV) oxide of a given concentration was additionally introduced into the electrolyte solutions. The photocatalytic activity of the obtained systems was assessed by the phenol oxidation reaction. It is shown that, as a result of anodic oxidation of the VT1-0 alloy in sulfuric and pyrophosphate electrolytes, it is possible to obtain mixed oxide systems of the Ti/TinOm·ZrO2 composition with a porous and microcrystalline surface structure and a zirconium content of up to 2 % by weight. It was found that an increase in the pH of the electrolyte leads to a significant decrease in the content of zirconium in the coatings. It is shown that the contact masses Ti/TiO2, Zr/ZrO2, Ti/TinOm·ZrO2 are photocatalytically active in the oxidation of phenol under the action of UV radiation, and the mixed Ti/TinOm·ZrO2 coatings formed from a sulfuric acid electrolyte exhibit a higher catalytic activity with respect to compared with both individual oxides and Ti/TinOm·ZrO2 deposited from pyrophosphate electrolytes. The results obtained indicate the possibility of creating photocatalytic converters using mixed oxide systems formed on metal supports for purifying wastewater from organic aromatic compounds. Keywords: coatings, titanium(IV) oxide, electrochemical anodizing, photocatalytic activity, zirconium(IV) oxide, organic aromatic pollutants, phenol, waste water, purification. Corresponding author Panasenrj V.A. е-mail: office@niochim.kharkov.ua
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38

TSODIKOV, M. V., O. V. BUKHTENKO, O. G. ELLERT, V. V. MARKEVICH, YU V. MAKSIMOV, and S. M. LOKTEV. "ChemInform Abstract: Synthesis and Structure of Mixed Metal Oxides Obtained by Reaction of Iron and Nickel Acetylacetonates with Hydrolysis Products of Titanium and Zirconium Alcoholates." ChemInform 22, no. 31 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199131036.

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39

Молвинских, Вера, Vera Molvinskikh, Надежда Белоконова, Nadezhda Belokonova, Татьяна Еловикова, Tat'yana Elovicova, Дарья Киселева, et al. "CLINICAL AND EXPERIMENTAL SUBSTANTIATION OF THE CHOICE OF TOOTHPASTES ON THE BASIS OF MONITORING THE COMPOSITION OF THE ORAL FLUID IN THE INHABITANTS OF INDUSTRIAL AREAS." Actual problems in dentistry 15, no. 1 (May 6, 2019): 33–37. http://dx.doi.org/10.18481/2077-7566-2019-15-1-33-37.

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The inhabitants of industrial areas are influenced by anthropogenic factors. Harmful chemicals enter the body from the air, drinking water, food and are found in the oral fluid, hard tooth tissues, dental deposits, biopsy of tissue structures and contribute to the development of caries and inflammatory periodontal diseases. Toothpastes and mouthwashes are used for prevention of major dental diseases. The toothpastes contain a variety of abrasives: silicon dioxide, calcium carbonate, titanium dioxide, calcium bicarbonate, hydroxyapatite, which can act as adsorbents of heavy metal compounds. Biomonitoring using inductively coupled plasma mass spectrometry (ICP-MS) allows to determine the micro-quantities of metals in blood, urine, human milk, hair and oral fluid. The study of oral hygiene products showed that toothpastes and mouthwashes, used by patients for prevention and treatment of inflammatory periodontal diseases, have an adsorption activity for metal ions. The article evaluates the adsorption efficiency of medical and preventive toothpaste relative to the metal ions (chromium, manganese, cadmium, lead, etc.) in the oral fluid of the inhabitants of industrial areas. The use of adsorption-effective toothpaste twice a day for two weeks showed a significant decrease in the concentration of metal ions in the mixed saliva of the inhabitants which are under the influence of unfavorable environmental factors. When using a toothpaste containing silicon and titanium oxides, the concentration of manganese, chromium, arsenic, lead and cadmium ions in the oral fluid decreases within 2 weeks. The modern method of ISP-MS is advisable to use for high-precision monitoring of the oral fluid ion composition in patients living in the industrial areas.
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40

Antonov, V. N., L. V. Bekenov, and A. N. Yaresko. "Electronic Structure of Strongly Correlated Systems." Advances in Condensed Matter Physics 2011 (2011): 1–107. http://dx.doi.org/10.1155/2011/298928.

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The article reviews the rich phenomena of metal-insulator transitions, anomalous metalicity, taking as examples iron and titanium oxides. The diverse phenomena include strong spin and orbital fluctuations, incoherence of charge dynamics, and phase transitions under control of key parameters such as band filling, bandwidth, and dimensionality. Another important phenomena presented in the article is a valence fluctuation which occur often in rare-earth compounds. We consider some Ce, Sm, Eu, Tm, and Yb compounds such as Ce, Sm and Tm monochalcogenides, Sm and Yb borides, mixed-valent and charge-ordered Sm, Eu and Yb pnictides and chalcogenides R4X3and R3X4(R = Sm, Eu, Yb; X = As, Sb, Bi), intermediate-valence YbInCu4and heavy-fermion compounds YbMCu4(M = Cu, Ag, Au, Pd). Issues addressed include the nature of the electronic ground states, the metal-insulator transition, the electronic and magnetic structures. The discussion includes key experiments, such as optical and magneto-optical spectroscopic measurements, x-ray photoemission and x-ray absorption, bremsstrahlung isochromat spectroscopy measurements as well as x-ray magnetic circular dichroism.
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41

Vettraino, M., M. Trudeau, and D. M. Antonelli. "Synthesis and Characterization of a New Family of Electroactive Alkali Metal Doped Mesoporous Nb, Ta, and Ti Oxides and Evidence for an Anderson Transition in Reduced Mesoporous Titanium Oxide." Inorganic Chemistry 40, no. 9 (April 2001): 2088–95. http://dx.doi.org/10.1021/ic0011359.

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42

Lewis III, D., M. Ashraf Imam, Arne W. Fliflet, Ralph W. Bruce, L. K. Kurihara, A. K. Kinkead, M. Lombardi, and Steven H. Gold. "Recent Advances in Microwave and Millimeter-Wave Processing of Materials." Materials Science Forum 539-543 (March 2007): 3249–54. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.3249.

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We are using 2.45 GHz (S-Band) microwave systems and an 83-GHz, gytrotron-based, millimeter-wave beam system in material processing and other areas. We use one 2.45 GHz system in preparation of nanophase metals, metal mixtures and metal oxides, via the patented continuous microwave polyol process, with potential for large scale, low cost production. Of interest are precious metals, mixtures of magnetic and nonmagnetic metals, and mixed metal oxides for ceramic precursors. The other S-Band systems are used to develop repair techniques for ceramic matrix composites where the repairs are heated to 200-1000°C. A portable, battery-powered system is being developed for field repairs, and promises to be much more practical than alternative approaches (e.g., heating blankets). The 83-GHz system is being used in rapid sintering of polycrystalline ceramic materials intended for use in high power solid state lasers, where the requirement if for sintering to transparency with high optical quality and good lasing efficiency. Transparent Yb-doped yttria has been produced with hybrid conventional/millimeter-wave sintering of nanophase powders, as well as theoretically dense YAG. Another application for the millimeterwave beam system is in consolidation and bonding of hard coatings to light alloys, such as SiC on titanium, where the beam system allows heating of the coating to very high temperatures without overheating the metallic substrate. Finally, the millimeter-wave system is being used in the development of millimeter-wave plasma-assisted diamond deposition, where the quasi-optical system has significant advantages over conventional microwave plasma-assisted diamond deposition. Results for these various areas will be presented and discussed.
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43

Crochet, Aurelien, Jean-Pierre Brog, and Katharina Fromm. "Cr(II) complex: water reductant and starting compound for new Cr(III) compounds." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1385. http://dx.doi.org/10.1107/s2053273314086148.

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The use of alkali aryloxide reagents in organo-metallic synthesis often depends on their solubility, a property derived from their structure. The regain of interest of alkali aryloxides also originates from the discovery of high-temperature superconducting compounds, which has generated a great interest in the formation of oxide materials and other ceramics. Thus, many alkoxides of yttrium and copper are common precursors for oxide materials. Moreover, the synthesis of heterobimetallic alkoxides has provided a facile route for obtaining soluble, volatile, and generally monomeric species. These heterobimetallic complexes can thus serve as valuable precursors for making metal oxides but it is not the only possible application for this type of compounds. These complexes can be used as starting compounds for syntheses of more complex structures. In this work, the salt elimination and ligand exchange reaction of chromium(II) chloride with lithium phenoxide yields a mixed metal lithium-chromium(II) phenoxide. Using this latter as intermediately formed starting material and combining the substitution reaction with an oxidation process, we have gained access to new polynuclear chromium(III) aryloxide complexes. While a 1D coordination polymer based on chromium(III) is obtained in a first reaction by serendipity, the controlled addition of water to the Cr(II) complex leads to three new discrete chromium(III) cluster compounds. The use of deuterated species allowed to confirm the oxidation based on the addition of water by detection of H2, HD and D2. During these investigations, we have also identified a THF-adduct of chromium(II) chloride, used in the literature as precursor in numerous syntheses, but with a hitherto unknown structure. Figure 1: Oxidation of a Cr(II) complex by water and formation of a new Cr(III) complex.
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44

Molina, J., C. Zúñiga, M. Moreno, W. Calleja, P. Rosales, R. Ambrosio, F. J. De la Hidalga, et al. "Physical and electrical characterization of TiO2 particles after high temperature processing and before and after ultraviolet irradiation." Canadian Journal of Physics 92, no. 7/8 (July 2014): 832–37. http://dx.doi.org/10.1139/cjp-2013-0603.

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In this work, rutile-phase TiO2 particles (r-TiO2, about 360 nm in size) are embedded within a silicon oxide matrix using different concentration ratios of r-TiO2 with respect to SiO2:H2O, so that suspensions of mixed TiO2:SiO2 oxides were obtained and analyzed. These TiO2:SiO2 suspensions were deposited on previously-cleaned crystalline silicon and quartz substrates so that thin films of TiO2:SiO2 were obtained. All films were then exposed to relatively high-temperature thermal treatments in nitrogen and different characterization techniques were used to determine their physical and electrical properties before and after ultraviolet (UV) irradiation. Before high thermal treatment, X-ray diffraction patterns show that the main diffraction peaks for the obtained TiO2:SiO2 films correspond to the crystalline phase of rutile-TiO2. Infrared analyses before and after thermal treatment show significant changes in the chemical bonding of the final films relative to the temperatures used during annealing. Also, UV–visible spectra provide a constant optical band gap for the films, independent of different TiO2 concentrations as expected. On the other hand, atomic-force microscopy measurements before and after UV irradiation show an appreciable difference in the grain size and surface morphology of the resulting TiO2:SiO2 oxides annealed at 1000 °C. Finally, photoelectrical I–V properties were obtained for all TiO2:SiO2 films by depositing ultrathin titanium stripes on top of the photoactive material and then, measuring the total current flowing through the metal electrode before and after UV irradiation. From these last measurements, a detectable increase in the I–V slope (lower resistance of the titanium stripe) is found for all samples during UV exposure, thus making this device to act as a simple photoresistor based on r-TiO2 particles.
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45

Hurley, John P., Carl Kelley, Norman Bornstein, and Ian G. Wright. "Corrosion of MA754 and MA956 in a Commercial Aluminum Melter." Materials Science Forum 595-598 (September 2008): 611–19. http://dx.doi.org/10.4028/www.scientific.net/msf.595-598.611.

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The University of North Dakota Energy & Environmental Research Center is working with Oak Ridge National Laboratory to test two oxide dispersion-strengthened alloys that could be used to construct very high-temperature heat recuperators for the aluminum-melting industry. For the initial tests, uncooled rings of MA754 and MA956 piping were exposed for 5½ months to gases leaving an aluminum melter furnace at 1200°–1290°C. The MA956 suffered spotty areas of severe corrosion and lost 25% of its weight. Scanning electron microscopy showed that there were small spots of alkali-rich corrosion products on the alloy surfaces, indicating the impact of droplets of fluxing agents. The corrosion products in these areas were mixed Fe, Cr, and Al oxides, which were depleted in Cr near the gas surface. However, Al concentrations in the remaining metal were typically between 3.5% and 4.0%, so there was a sufficient reservoir of Al remaining in the alloy to prevent simple breakaway corrosion which could have occurred if the Al were significantly depleted. The MA754 lost approximately 15% of its weight and showed void formation within 2 mm of the gas–metal surfaces. Within the porous area, the Cr had largely segregated into oxide precipitates up to 50 9m in diameter, leaving the remaining metal Ni-rich. Below the porous layer, the alloy composition was relatively unchanged. Remains of Na- and Al-rich particles that had impacted the surface sporadically were visible but had not obviously affected the surface scale as they had with the MA956.
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46

Lewicka, Ewa, and Anita Trenczek-Zajac. "Investigations of Feldspar-Quartz Raw Materials After Firing: Effect of Various Na2O/K2O Ratio and Synthetic Pigments Addition." Minerals 10, no. 7 (July 21, 2020): 646. http://dx.doi.org/10.3390/min10070646.

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Different techniques (chemical analysis, X-ray diffraction, Mössbauer spectroscopy, UV-Vis-NIR spectrophotometry and chromaticity measurements) were used to study the color variation of feldspathic raw materials after firing at 1200 °C. Two varieties of feldspar-quartz grits (with Na2O or K2O prevalence) doped with synthetic pigments (hematite and rutile) were heat-treated in an oxidizing atmosphere. The results obtained indicate that the color of the ceramic body after firing may not only depend on the presence and analytical content of coloring elements (such as iron and titanium), but on their valence state and the chemical characteristics of the melt itself. The prevalence of larger alkali K+ ions over Na+ ions may cause the reduction of the coordination number of iron. This has a significant effect on the length of the Fe–O bond, which in turn influences the capacity for light absorption of a specific wavelength. The results of spectrophotometric measurements showed pronounced disparity between the raw materials and samples doped with coloring oxides. The introduction of synthetic pigments caused clear changes in the spectral dependence of the total absorbance. The absorbance increased in the whole measuring range, in particular in the visible part of the spectrum. Furthermore, a red-shift of the absorption bands towards longer wavelengths attributed to oxygen-metal charge transfer (OMCT) interactions between Fe3+ and O2− ions as well as to d-d transitions within Fe3+ ions was observed.
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47

Zinner, Ernst. "Stardust in meteorites: A link between stars and the Solar System." Proceedings of the International Astronomical Union 4, S251 (February 2008): 341–42. http://dx.doi.org/10.1017/s174392130802190x.

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AbstractUltimately, all of the solids in the Solar System, including ourselves, consist of elements that were made in stars by stellar nucelosynthesis. However, most of the material from many different stellar sources that went into the making of the Solar System was thoroughly mixed, obliterating any information about its origin. An exception are tiny grains of preserved stardust found in primitive meteorites, micrometeorites, and interplanetary dust particles. These μm- and sub-μm-sized presolar grains are recognized as stardust by their isotopic compositions, which are completely different from those of the Solar System. They condensed in outflows from late-type stars and in SN ejecta and were included in meteorites, from which they can be isolated and studied for their isotopic compositions in the laboratory. Thus these grains constitute a link between us and our stellar ancestors. They provide new information on stellar evolution, nucleosynthesis, mixing processes in asymptotic giant branch (AGB) stars and supernovae, and galactic chemical evolution. Red giants, AGB stars, Type II supernovae, and possibly novae have been identified as stellar sources of the grains. Stardust phases identified so far include silicates, oxides such as corundum, spinel, and hibonite, graphite, silicon carbide, silicon nitride, titanium carbide, and Fe-Ni metal.
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48

Mantyi, H. C., L. A. Cornish, Lesley H. Chown, and I. Alain Mwamba. "Investigating the High Temperature Oxidation Behavior of TiAl-Based Alloys with Nickel and Ruthenium Additions." Advanced Materials Research 1019 (October 2014): 294–301. http://dx.doi.org/10.4028/www.scientific.net/amr.1019.294.

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Pure powders of titanium, aluminium, nickel and ruthenium were mechanically alloyed and melted in a button arc furnace under an argon atmosphere to produce two alloys of composition Ti-52.5Al-10.0Ni (at.%) and Ti-52.5Al-10.0Ni-0.2Ru (at.%). The alloys were then cut and metallographically prepared. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were used to characterize the samples. Thermogravimetric analysis (TGA) was used to analyze the oxidation behavior from room temperature up to 1050°C. The alloys were also oxidized in air at 1050°C for 120 hours. The Ti-52.5Al-10.0Ni (at.%) alloy formed dendrites of γ-TiAl (55.6 at.% Al) surrounded by a eutectic of γ-TiAl + Al3NiTi2 (τ3) phases. The Ti-52.5Al-10.0Ni-0.2Ru (at.%) alloy formed dendrites of γ-TiAl (53.6 at.% Al) surrounded by a eutectic of γ-TiAl + Al3NiTi2 (τ3). The ruthenium was mostly in solid solution (0.3 at.%) in the Al3NiTi2 (τ3) phase, although traces of it were present in the dendrites (0.1 at.% Ru). When oxidized in air from room temperature to 1050°C, the as-cast Ti-52.5Al-10.0Ni-0.2Ru (at.%) had a mass gain of 0.60% and the as-cast Ti-52.5Al-10.0Ni (at.%) had a mass gain of 0.97%. Isothermal oxidation of both alloys at 1050°C for 120 hours formed mixed metal oxides of TiO2+Al2O3 on the surface.
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49

Levytska, Svitlana, and Artur Mylin. "CATALYTIC SYNTHESIS OF GLYCOLIC ACID AND ITS METHYL ESTER FROM GLYOXAL." Ukrainian Chemistry Journal 86, no. 12 (January 15, 2021): 134–45. http://dx.doi.org/10.33609/2708-129x.86.12.2020.134-145.

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Glycolic acid is practically non-toxic to humans, has bactericidal properties and a weak odor, which makes it widely used in food (as a flavoring and preservative) textile (as a dye and tanning agent), cosmetics and pharmaceuticals (as a keratolytic and a skin care agen). Glycolic acid can also be converted to biodegradable polymer with good mechanical properties and excellent biocompatibility, wich is used for different medical applications. In industry, glycolic acid is obtained by carbonylation of formaldehyde using as catalysts quite aggressive acids (H2SO4, HCl, HF), hydrolysis of hydroxyacetonitrile under the influence of acids (H2SO3, H3PO3) or the enzyme nitrilase and saponification of chloroacetic acid with a double excess of alkali (NaOH, KOH). In addition to the non-ecological nature of used raw materials for this process there is a problem associated of purification of the product especially from homogeneous catalysts. The process of obtaining glycolic acid and its methyl ester from glyoxal over a number of solid acid and basic catalysts based on mixed oxides of aluminum, tin, titanium, zirconium, and magnesium has been studied. In study, commercially available 40% aqueous solution of glyoxal, anhydrous glyoxal trimer (Sigma-Aldrich, 95%) and methanol (99%, Merck) were used. Catalytic experiments were carried out in rotated steel autoclave (60 rpm) for 0.5–5 hours at temperatures of 100–170 °C. It is shown that the synthesized oxide catalysts after 5 h of reaction at 100 °C provide up to 98% conversion of an aqueous solution of glyoxal to glycolic acid with a selectivity of 83–100%.It was found that over the studied basic catalysts the undesirable oligomerization process of the formed glycolic acid occurred to a lesser extent and as a result the yield of monoglycolic acid was much higher (60–69%) than over acid catalysts (28–40%). The most selective MgO-ZrO2 catalyst after 1 h of the reaction at 150 °C of methanolicglyoxal solution provides almost 100% yield of methyl glycolate.
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50

Chandler, Clive D., Mark J. Hampden-Smith, and Jeffrey Brinker. "Synthetic Routes to Perovskite Phase Mixed Metal Oxides." MRS Proceedings 243 (1991). http://dx.doi.org/10.1557/proc-243-237.

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AbstractWe are developing strategies to form single-component precursors to perovskite phase mixed metal oxides where the stoichiometry of the precursor is fixed at the molecular level to be that of the final desired phase. These strategies ean be applied to the formation of perovskite phase thin films. Two such methods are described herein, relying on ester elimination and alcohol elimination reactions. We have found the reaction between lead(II) acetate and titanium(IV) isopropoxide in ethanol results in ligand redistribution at room temperature. Reactions between (β-diketonate)2M(OR)2 where M = Ti, Zr and Sn and lead(II) acetate do not result in any detectable ester elimination under the reaction conditions employed, and this approach was not successful. Alcohol elimination experiments have been explored as an alternative strategy using a bifunctional glycolate ligand. Lead carbonate reacted with glycolic acid to form the corresponding lead glycolate complex Pb(O2CCH2OH)2. This compound reacted with (β-diketonate)2M(OR)2, M = Ti and Sn, to eliminate two equivalents of alcohol and form the corresponding single component (β-diketonate)2M(OCH2CO2)2Pb complexes. These complexes start to thermally decompose at 150°C and loss of weight is complete by 450°C to yield a product whose weight loss corresponds to the formation of PbTiO3 for M = Ti. Bulk thermolysis of a sample of (dpm)2Ti(OCH2CO2)2Pb at 400°C resulted in formation of crystalline perovskite phase lead titanate together with PbO, massicot and α-PbO phases.
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