Artykuły w czasopismach: „TiO2”

1

Wang, Zhen, Qifeng Shu i Kuochih Chou. "Study on Structure Characteristics of B2O3 and TiO2-bearing F-Free Mold Flux by Raman Spectroscopy". High Temperature Materials and Processes 32, nr 3 (14.06.2013): 265–73. http://dx.doi.org/10.1515/htmp-2012-0137.

Pełny tekst źródła

Streszczenie:

AbstractStructure characteristics of fluoride-Free mold flux containing simultaneously B2O3 and TiO2 have been investigated by Raman spectroscopy in this work. Raman spectra for glass samples with different basicities, different contents of TiO2 and B2O3 were recorded during the experiments. According to the experiments results, increase of TiO2 content leads to the appearance of [TiO4] and [TiO6] structure groups, and [TiO4] becomes the main structure unit in the system. TiO2 produces a certain destructive effect on Si-O-Si network structure as well as large borate group and conducive to the formation of some other complex structure groups, such as (Si,Ti) coupling in sheet unit. It can be concluded that, with the increase of B2O3, the ratio of mixing of the Q0 structure unit and [TiO4] structural group decrease and the ratio of sheet structure unit increase, and there forms large borate group. Existence of B2O3 increases polymerization degree of the slag system. In addition, increasing basicity causes to the decrease of Q2 and sheet structure unit and increase of mixing of the Q0 structure unit and [TiO4] structural group, and weakening the large borate group. It could be concluded that the increase of basicity reduces the degree of polymerization of the system.

Style APA, Harvard, Vancouver, ISO itp.

2

Liu, Xiongzhang, Xixi Li, Xue Lei, Deping Zhang, Zhijun Liu, Xueyuan Long i Rongzhou Gong. "Research on dielectric and microwave absorbing properties of TiO₂/TiB₂/Thermoplastic polyurethanes (TPU) composite materials". Journal of Physics: Conference Series 2248, nr 1 (1.04.2022): 012012. http://dx.doi.org/10.1088/1742-6596/2248/1/012012.

Pełny tekst źródła

Streszczenie:

Abstract TiO2/TiB2 materials are prepared by the carbothermal method and high-temperature calcination. Further, the phase composition, microstructure, dielectric and electromagnetic (EM) wave absorption characteristics are investigated. The results display that the product is composed of TiO2, TiB2 and impurity phases. The complex permittivity increases at elevated TiO2/TiB2 loading and slowly decreases with rising frequency in 2-18 GHz. When the TiO2/TiB2 content is 45 wt%, the minimum reflection loss (RLmin ) reaches -43.12 dB at 11.68 GHz with a thickness of 1.9 mm. The effective absorption band (EAB, RL<-10 dB) can reach 3.68 GHz at 2.3 mm as the TiO2/TiB2 content is 30 wt%. The enhanced EM wave absorption owes to the strong polarization loss and high conductivity loss. It goes without saying that TiO2/TiB2 materials can acquire important breakthroughs in the development of novel EM wave absorbers with outstanding absorption loss, wider EAB and smaller thicknesses.

Style APA, Harvard, Vancouver, ISO itp.

3

Zhu, He Guo, Jin Min, Da Chu i Huan Wang. "Study on the Reaction Mechanism of (α-Al₂O₃+TiB₂+TiC)/Al Composites Fabricated by Al-TiO₂-B₄C System". Advanced Materials Research 150-151 (październik 2010): 84–87. http://dx.doi.org/10.4028/www.scientific.net/amr.150-151.84.

Pełny tekst źródła

Streszczenie:

The composites (-Al2O3+TiB2+TiC)/Al has been fabricated by using exothermic dispersion synthesis. Thermodynamic analysis indicated that the reaction between the Al and TiO2 can spontaneously occur due to the negative Gibbs free energy of the Al-TiO2 reaction system. With the increase of B4C/TiO2 mole ratios, the exothermic peaks increase move to the higher temperature and the corresponding ignite temperatures also increase. The reaction results indicate that when the B4C/TiO2＝0, the reinforcements are composed of -Al2O3, Al3Ti, with the increase of B4C/TiO2, the amount of Al3Ti decreases and the TiC and TiB2 form simultaneously. When the B4C/TiO2 increases to 1/3, the Al3Ti almost disappear and the reinforcements of the composites are consisted of -Al2O3, TiC and TiB2.

Style APA, Harvard, Vancouver, ISO itp.

4

Kim, Sang-Cheol, Sung-Hong Hahn, Eui-Jung Kim, Chung-Woo Lee, Jong-Hyun Joo i Goo-Cheol Kim. "Characteristics of TiO2 and Ag/TiO2 optical thin film by Co-sputtering method". Korean Journal of Optics and Photonics 16, nr 2 (1.02.2005): 168–73. http://dx.doi.org/10.3807/kjop.2005.16.2.168.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

5

Zhu, De Gui, Hong Liang Sun, Yu Shu Wang i Liang Hui Wang. "Oxidation Behaviors of TiB₂-TiC_X and TiB₂-TiC_X/15SiC Ceramics". Advanced Materials Research 105-106 (kwiecień 2010): 179–83. http://dx.doi.org/10.4028/www.scientific.net/amr.105-106.179.

Pełny tekst źródła

Streszczenie:

Fully dense samples of TiB2-TiCX and TiB2-TiCX/15SiC ceramic composites were fabricated by in-situ synthesis under hot isostatic pressing from TiH2, B4C and SiC powders. Their oxidized behaviors at different temperatures were tested. Optical micrograph studies and thermo-gravimetric analyses show that the highest effective temperature of oxidation resistance is 700°C for TiB2-TiCX, and 1100°C for TiB2-TiCX/15SiC. The weight gain of TiB2-TiCX/15SiC below 1100°C is quite low, and it rises up suddenly when the temperature reaches 1200°C. Thus, the highest effective temperature of oxidation resistance is 1100°C for TiB2-TiCX/15SiC. The oxidation dynamic curves of TiB2-TiCX/15SiC ceramics accord with the parabola’s law. The activation energy of TiB2-TiCx/15SiC (189.87kJ.mol-1) is higher than that of TiB2-TiCx (96.44kJ.mol-1). In the oxidation process of TiB2-TiCx/15SiC, TiB2 reacts with oxygen and generates TiO2 and B2O3 at first. A layer of whole homogeneous oxide film cannot be formed, in the mean time, the oxidation of TiC begins. When temperature goes up to 1000°C, TiC phase is totally oxidized. SiC is oxidized to SiO2 at about 900°C, Meanwhile, TiO2 forms denser film than B2O3, which grows and covers the surface of the material, and gives better property of oxidation resistance.

Style APA, Harvard, Vancouver, ISO itp.

6

Huang, Fei, Zheng Yi Fu, Ai Hua Yan, Tie Kun Jia, Wei Min Wang, Hao Wang, Yu Cheng Wang i Jin Yong Zhang. "Effect of Hydrogen Peroxide on TiB₂-Based Materials". Advanced Materials Research 66 (kwiecień 2009): 222–25. http://dx.doi.org/10.4028/www.scientific.net/amr.66.222.

Pełny tekst źródła

Streszczenie:

TiO2/TiB2 heterostructures were successfully synthesized by a facile hydrothermal approach in an aqueous solution of hydrogen peroxide (H2O2). The influence of H2O2 on TiB2-based materials was systematically investigated using X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that TiB2 is prone to oxidize in the presence of H2O2. TiO2/TiB2 heterostructure which high-density anatase-TiO2 stand on the surface can be gained in the presence of H2O2 solvent and the final composition can be controlled by the temperature and time. The investigation may provide a path to further understand the chemical property of TiB2-based materials and synthesis method of heterostructure.

Style APA, Harvard, Vancouver, ISO itp.

7

Svec, Pavol, i L’ubomír Caplovic. "Microstructure and mechanical properties of b4c-tib2 composites reactive sintered from B4C + TiO2 precursors". Processing and Application of Ceramics 16, nr 4 (2022): 358–66. http://dx.doi.org/10.2298/pac2204358s.

Pełny tekst źródła

Streszczenie:

Ceramic composites consisting of a boron carbide (B4C) matrix and titanium diboride (TiB2) secondary phase were obtained by reactive sintering from boron carbide powder with 40 and 50wt.% of titanium dioxide (TiO2) additive. The same sintering temperature of 1850?C and pressure of 35MPa, but different sintering times from 15 to 60min, were applied during reactive hot pressing of the composites in vacuum. The effects of TiO2 content and sintering time on phase compositions, microstructures and mechanical properties of the composites were studied. The TiO2 additive enhanced densification of the B4C-TiB2 ceramic composites. Both Vickers hardness and the fracture toughness of the composites increased with prolongation of sintering time. The highest hardness of 29.8GPa was achieved for the composite with 29.6 vol.% of TiB2 obtained by sintering of the precursor with 40wt.% of TiO2 additive for 60min. The fracture toughness reached a maximum value of 7.5MPa?m1/2 for the composite containing 40.2 vol.% of TiB2, which was fabricated by reactive sintering of the precursor with 50wt.% of TiO2 additive for 60min.

Style APA, Harvard, Vancouver, ISO itp.

8

Gao, Ji Wei, Qian Hong Shen, Ming Fang, Ping Wang i Li Li. "Preparation and Investigation of TiO₂ Sol Containing Nanometer Anatase Crystalline Grains". Key Engineering Materials 336-338 (kwiecień 2007): 2350–52. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.2350.

Pełny tekst źródła

Streszczenie:

TiO2 sol containing nano anatase crystalline grains was prepared using Ti(OC4H9)4 as a precursor in a water-excessive reaction system. The processes of hydrolytic-polymeric reactions and the structures of the products were analyzed. It was found that the -OC4H9 radicals previously linked to Ti atom in Ti (OC4H9) 4 molecular are broken, and there is no organic radicals linked to Ti atoms in the final sol. The structure of particles in the sol changes along with time from tetrahedral [TiO4] to octahedral [TiO6], with the coordination number changing from 3.14 to 5.18, accordingly. Therefore, the structure becomes closer to an anatase, which is octahedral [TiO6] with a coordination number of 6.0. Transmission electron microscope micrograph also reveals the foursquare projection shape of crystalline grains with a size of 200 nm in the sol. As the particles in the sol have a quasi anatase structure, the TiO2 sol can directly photodegrade Rhodamine B under Ultraviolet illumination with a rate of 62.35%.

Style APA, Harvard, Vancouver, ISO itp.

9

Gnedenkov, S. V., D. P. Opra, V. G. Kuryavyi, S. L. Sinebryukhov, A. Yu Ustinov i V. I. Sergienko. "Nanostructured TiO2–TiOF2 composite as anode material for Li-ion battery". Electrochemical Energetics 14, nr 2 (2014): 68–77. http://dx.doi.org/10.18500/1608-4039-2014-14-2-68-77.

Pełny tekst źródła

Streszczenie:

TiO2–TiOF2 composite has been synthesized in plasma by the unique method of pulsed high-voltage discharge due to the destruction of Ti electrodes and polytetrafluoroethylene wire. TiO2–TiOF2 features have been investigated by scanning electron microscopy, X-ray diffraction, infrared spectroscopy, energy-dispersive X-ray analysis, Raman spectroscopy, and X-ray photoelectron spectroscopy. It has been shown that composite with a porous surface morphology includes the nanocrystallites of sizes ranging from 40 to 200 nm. The average diameter of the pore is 3–5 nm. Electrochemical characterization of the nanostructured porous TiO2–TiOF2 composite was carried out in view of its application as an anode-active material for Li-ion battery. The initial high specific capacity of the composite is equal up to 1370 mAh g−1 at a rate of 20 mA g−1. It is higher (due to the TiO2 presence) in comparison with up-to-date TiOF2 anode materials. Galvanostatic charge–discharge cycling of the Li/TiO2–TiOF2 cell in the range of 3.0–0.005 V yields 205 mAh g−1 after 20 cycles.

Style APA, Harvard, Vancouver, ISO itp.

10

Chan, Chao Chin, Chean Cheng Su, Chien Chen Diao i Cheng Fu Yang. "Low Temperature Sintering (Ba_1-xSr_x)TiO₃ Ceramics by Using CuO-TiO₂ Mixture as Sintering Aid". Key Engineering Materials 336-338 (kwiecień 2007): 62–65. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.62.

Pełny tekst źródła

Streszczenie:

1wt% CuO-TiO2 (molar ratio, CuO/TiO2= 1) mixture is added as the liquid phase sintering aid to develop the sintering and dielectric characteristics of (Ba1-xSrx)TiO3 (x=0, 0.1, and 0.2) ceramics. The crystal characteristics of calcined (Ba1-xSrx)TiO3 powders and sintered (Ba1-xSrx)TiO3 ceramics are developed by using X-ray diffraction method. The calcined (Ba1-xSrx)TiO3 powders and 1050oC-sintered (Ba1-xSrx)TiO3 ceramics reveal a tetragonal or pseudo-cubic structure and the 1150oC-sintered(Ba1-xSrx)TiO3 ceramics reveal a tetragonal structure. Sintered at 1100oC, the (Ba1-xSrx)TiO3 ceramics present a porous structure; Sintered at 1150oC, the (Ba1-xSrx)TiO3 ceramics present a uniform growth. The grain size decreases with the increase of SrO content. In this study, the dielectric characteristics of CuO-TiO2 mixture-fluxed (Ba1-xSrx)TiO3 ceramics are also developed.

Style APA, Harvard, Vancouver, ISO itp.

11

Wang, Gui Song, i Lin Geng. "Microstructure Formation Mechanism of (Al₂O₃+TiB₂+Al₃Ti)/Al Composites Fabricated by Reactive Hot Pressing". Key Engineering Materials 353-358 (wrzesień 2007): 1439–42. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.1439.

Pełny tekst źródła

Streszczenie:

The two (Al2O3+TiB2+Al3Ti)/Al composites were fabricated from Al-B2O3-TiO2 and Al-B-TiO2 raw powders by reactive hot pressing, respectively. The microstructure of in situ two composites was analyzed by OM, SEM and TEM. The results showed that coarse Al3Ti blocks with several tens of micrometers size were formed during hot pressing. The equiaxed Al2O3 particulates and hexagonal TiB2 particulates with finer sizes were formed in the composites simultaneously. The microstructure formation mechanism of (Al2O3+TiB2+Al3Ti)/Al composites were discussed. The results showed that Al2O3 reinforcements were formed on the surface of TiO2 or B2O3 powder and TiB2 particles were formed on B or B2O3 powders. The formation of coarse Al3Ti block is result from continuous diffusion of Ti in liquid Al during reactive hot pressing. In addition, there are fine Al3Ti precipitates exist in the composite fabricated from Al-B-TiO2 powders. This contributes to the improved mechanical properties in terms of yield and ultimate stresses and Young’s modulus of the composite.

Style APA, Harvard, Vancouver, ISO itp.

12

Riyani, Kapti, i Tien Setyaningtyas. "PEMANFAATAN FOTOKATALIS TiO2 UNTUK MEREDUKSI ION TIMBAL". Molekul 4, nr 1 (1.05.2009): 6. http://dx.doi.org/10.20884/1.jm.2009.4.1.57.

Pełny tekst źródła

Streszczenie:

TiO2 photocatalyst can be used to reduce heavy metal ions into common metal ion or metal ion with lower coordination number. This research aimed to (1) study the influence of pH on the photoreduction activity of Pb2+ion by TiO2, (2) study the influence of hole scavenger on the photoreduction activity of Pb2+ ion by TiO2, (3) study the influence of light source on the photoreduction activity of Pb2+ ion by TiO2. The method used on this research is laboratory experiment consist of the making of TiO2 thin film, standard Pb2+ photoreduction with the variation of pH, standard Pb2+ photoreduction with the variation of light source. The results of Pb2+ photoreduction are analyzed by Atomic Absorption Spectroscopy. The result of the research showed that the activity of TiO2 to reduce Pb2+ can be optimum at pH 6, oxalic acid as hole scavenger and UV lamp use. The sunlight can also be used as the light source to reduce Pb2+ by TiO2 photocatalyst.

Style APA, Harvard, Vancouver, ISO itp.

13

Chen, Chin Sheng, H. C. Cheng, S. Y. Lee, Chaung Chih Chan i K. L. Ou. "Effect of Nanostructured TiH₂ on the Formation of Multimeshworked and Nanoporous TiO₂ by Cathodic-Anodization Treatment". Key Engineering Materials 339 (maj 2007): 463–68. http://dx.doi.org/10.4028/www.scientific.net/kem.339.463.

Pełny tekst źródła

Streszczenie:

Cathodic-anodization process was performed to treat titanium sheets to improve biocompatible performance. Grazing incident X-ray diffraction, transmission electron microscopy, scanning electron microscopy and electrochemical measurement were used to evaluate the influence of hydrogen on the formation of nanoporous TiO2. Multimeshworked and nanoporous TiO2 was observed after treatment with cathodic-anodization process. The nanoporous oxide layer is hard to form without nano-TiH2. The nano-TiH2 plays an important role in forming multimeshworked and nanostructured TiO2 layer. Hydrogen charging by cathodization is believed to enhance the formation of nanoporous oxide film and thus promote biocompatibility.

Style APA, Harvard, Vancouver, ISO itp.

14

Gambini, Marco, Roberto Montanari, Maria Richetta, Tommaso Stilo, Alessandra Varone i Michela Vellini. "Hydrogen Release from Oxidized Titanium Hydride". Materials Science Forum 941 (grudzień 2018): 2203–8. http://dx.doi.org/10.4028/www.scientific.net/msf.941.2203.

Pełny tekst źródła

Streszczenie:

Hydrogen storage is one of the most important industrial applications of titanium hydride (TiH2). A critical issue is the hydrogen release rate that strongly depends on the surface structure of TiH2 particles. This work reports the results of an experimental campaign carried out on TiH2 powders submitted to heat treatments in air at different temperatures and treatment times. After each heat treatment the TiH2 powders were examined by X-ray diffraction (XRD) and the results evidenced that the surface layer consists of TiO2 and Ti2O. Titanium oxide formation has been monitored by XRD at high temperature. Hydrogen release during heating of oxidized powders was investigated through temperature programmed desorption (TPD). Residual hydrogen in TiH2 depends on the specific treatment: higher temperature and soaking time of the treatment, lower its content.

Style APA, Harvard, Vancouver, ISO itp.

15

Goshkoderya, M. E., T. I. Bobkova, S. P. Bogdanov, A. V. Krasikov, M. V. Staritsyn i A. A. Kashirina. "Spraying wear-resistant coatings from clad powders TiB2/Ti and HfB2/Ti". Izvestiya. Ferrous Metallurgy 66, nr 1 (20.02.2023): 27–34. http://dx.doi.org/10.17073/0368-0797-2023-1-27-34.

Pełny tekst źródła

Streszczenie:

The present work considers the results on synthesis of composite clad powder systems with the “core-shell” type of structure for spraying wear-resistant metal-ceramic coatings. Powders of highly hard TiB2 and HfB2 borides were used as a core for the synthesis of a composite powder, and titanium was used to create coating on their surface. The cladding layer is synthesized by the iodine transport method. Powder cladding uses the method of detecting one component on another gas transport path, the agent of which is contact iodine. The deposition of composite clad powders of the TiB2 /Ti and HfB2 /Ti systems is implemented by the microplasma method, which, in contrast to the classical plasma deposition, makes it possible to dissolve transformations in composite powders due to thermal action. In the study of transverse microsections of sprayed coatings, it was found that during microplasma spraying, titanium is saturated with oxygen, forming a titanium dioxide phase, as a result of which the clad composite powder of systems TiB2 /Ti and HfB2 /Ti are converted into coatings from systems TiB2 (TiB)/Ti(TiO2 ) and HfB2 /Ti(TiO2 ). Features of the composition in terms of coating thickness were revealed. The study of hardness shows that the integral value of microhardness for a coating based on titanium diboride is 1300 HV. Coating based on hafnium diboride has integral microhardness of about 1600 HV. When checking the wear resistance, pairs with TiB2 (TiB)/Ti(TiO2 ) and HfB2 /Ti(TiO2 ) coatings were mated with a counterbody from the 45Kh sample without coatings and together with each other. Despite the lower microhardness, the most wear-resistant is coating of TiB2 (TiB)/Ti(TiO2 ) system.

Style APA, Harvard, Vancouver, ISO itp.

16

Sundaram, V., K. V. Logan i R. F. Speyer. "Reaction path in the magnesium thermite reaction to synthesize titanium diboride". Journal of Materials Research 12, nr 10 (październik 1997): 2657–64. http://dx.doi.org/10.1557/jmr.1997.0355.

Pełny tekst źródła

Streszczenie:

TiB2, along with MgO and Mg3B2O6, was formed by a thermite reaction between Mg, amorphous B2O3, and TiO2 powders in argon. The mixture 5Mg–TiO2–B2O3 along with binary mixtures and single components were analyzed using differential thermal analysis (DTA) and x-ray diffraction (XRD). Large (25 g) specimens were also ignited in bulk using a resistance-heated nichrome wire. The reaction path in forming TiB2 in the three component mixture was deduced. Mg reduces TiO2 and B2O3 to form Ti and MgB2, respectively, which in turn react to form TiB2. In an oxidizing atmosphere, the significant speed of the reaction permitted solid state reaction to form TiB2 before atmospheric oxygen could diffuse into the powder mass and react to form oxide phases. Thermite reactions in air have the advantage (over furnace heating in air) of not providing time at elevated temperatures for Mg and intermediate products to become consumed in the formation of oxides, nor time for oxidation degradation of TiB2.

Style APA, Harvard, Vancouver, ISO itp.

17

Arutanti, Osi, Sandra Sundari Nurmala, Khairurrijal i Mikrajuddin Abdullah. "Design of Hot Roll Press to Fabricate TiO₂-Coated Fiber for Decomposing Rhodamine B in Water". Materials Science Forum 737 (styczeń 2013): 33–36. http://dx.doi.org/10.4028/www.scientific.net/msf.737.33.

Pełny tekst źródła

Streszczenie:

We have designed new coating equipment for applying nanoparticles of TiO2 on nylon fiber surfaces. A roll hot press with a motor speed of 1740 rpm was able to synthesis ±227 cm/min coated fibers. This equipment is simple and does not require any adhesive materials for attaching Ti02 nanoparticles on the fiber surface. The fiber was passed through a dispersion of TiO2 nanoparticles and then passed through a roll hot press at heating temperature between 600C and 700C. The TiO2-coated fibers were then used for decomposing rhodB-solutions under solar illumination. We observed the TiO2-coated fibers did not affect to properties of TiO2 as catalyst in photocatalysis. The best result was observed when 0,5 gr TiO2-coated fibers were suspended into 250 ml of rhodB-solution in water with a concentration of 1,6 %w/v.

Style APA, Harvard, Vancouver, ISO itp.

18

Nature, Science. "The Influence of Calcination Temperatures in TiO2 Impregnated Ouw’s Natural Clay on Its Degradation Activity of Methylene Blue Dye". SCIENCE NATURE 1, nr 1 (13.12.2018): 008–14. http://dx.doi.org/10.30598/snvol1iss1pp008-014year2018.

Pełny tekst źródła

Streszczenie:

The influence of calcination temperatures in TiO2 impregnated Ouw’s natural clay on its degradation activity of methylene blue dye has been done. Calcination process was conducted at various temperatures of 200, 300, and 400 oC. The characterization of TiO2 impregnated clay’s structure was examined by IR analysis. The result showed that Ouw’s natural clay has characterized vibrations of montmorillonite and thermal effect didn’t affect the structure of TiO2 impregnated clay. The highest result of methylene blue’s degradation occurred in the addition of TiO2 impregnated clay calcinated at 200 oC (98.69%). This result was found that calcination temperatures of impregnation process were significantly affect the degradation activity of TiO2 impregnated clays.

Style APA, Harvard, Vancouver, ISO itp.

19

Nature, Science. "The Influence of Calcination Temperatures in TiO2 Impregnated Ouw’s Natural Clay on Its Degradation Activity of Methylene Blue Dye". SCIENCE NATURE 1, nr 1 (13.12.2018): 008–14. http://dx.doi.org/10.30598/vol1iss1pp008-014year2018.

Pełny tekst źródła

Streszczenie:

The influence of calcination temperatures in TiO2 impregnated Ouw’s natural clay on its degradation activity of methylene blue dye has been done. Calcination process was conducted at various temperatures of 200, 300, and 400 oC. The characterization of TiO2 impregnated clay’s structure was examined by IR analysis. The result showed that Ouw’s natural clay has characterized vibrations of montmorillonite and thermal effect didn’t affect the structure of TiO2 impregnated clay. The highest result of methylene blue’s degradation occurred in the addition of TiO2 impregnated clay calcinated at 200 oC (98.69%). This result was found that calcination temperatures of impregnation process were significantly affect the degradation activity of TiO2 impregnated clays.

Style APA, Harvard, Vancouver, ISO itp.

20

Astuti, Astuti, i Sulastriya Ningsi. "Sintesis Dan Karakterisasi Nanopartikel Titanium Dioksida (TiO2) Menggunakan Metode Sonokimia". JURNAL ILMU FISIKA | UNIVERSITAS ANDALAS 9, nr 1 (23.03.2017): 26–32. http://dx.doi.org/10.25077/jif.9.1.26-32.2017.

Pełny tekst źródła

Streszczenie:

Telah dilakukan sintesis dan karakterisasi nanopartikel Titanium dioksida (TiO2) menggunakan metode sonokimia dengan larutan induk TiCl4. Sintesis dilakukan dengan variasi waktu kalsinasi di dalam tanur 1 jam, 2 jam, 3 jam, dan 6 jam. Identifikasi sifat-sifat dari TiO2 hasil sintesis melalui SEM (Scanning Electron Microscopy) dan XRD (X-ray Diffraction). Didapatkan bahwa waktu pada proses kalsinasi mempengaruhi ukuran dan morfologi partikel TiO2. Morfologi permukaan yang paling seragam terdapat pada sampel D(6 jam kalsinasi) dan kandungan anatase terbesar pada sampel B (2 jam kalsinasi). Nanopartikel TiO2 hasil sintesis tersebut berpotensi untuk diaplikasikan sebagai fotokatalis pada sel surya DSSC. Kata kunci: Nanopartikel TiO2, kalsinasi, dan sonokimia

Style APA, Harvard, Vancouver, ISO itp.

21

Han, Aiguo, Mei Li, Shengbo Zhang, Xinli Zhu, Jinyu Han, Qingfeng Ge i Hua Wang. "Ti3+ Defective SnS2/TiO2 Heterojunction Photocatalyst for Visible-Light Driven Reduction of CO2 to CO with High Selectivity". Catalysts 9, nr 11 (6.11.2019): 927. http://dx.doi.org/10.3390/catal9110927.

Pełny tekst źródła

Streszczenie:

In recent years, defective TiO2-based composite nanomaterials have received much attention in the field of photocatalysis. In this work, TiB2 was used as a precursor to successfully prepare Ti3+ defective TiO2 (TiO2-B) with a truncated bipyramidal structure by a one-step method. Then, the SnS2 nanosheets were assembled onto the as-prepared TiO2-B through simple hydrothermal reaction. TiO2-B exhibits strong visible light absorption properties, but the recombination rate of the photo-generated electron-hole pair was high and does not exhibit ideal photocatalytic performance. Upon introducing SnS2, the heterojunction catalyst SnS2-Ti3+ defective TiO2 (SnS2/TiO2-B) not only possesses the strong light absorption from UV to visible light region, the lowest photo-generated charge recombination rate but also achieves a more negative conduction band potential than the reduction potential of CO2 to CO, and thereby, exhibits the significantly enhanced selectivity and yield of CO in photocatalytic CO2 reduction. Notably, SnS2/TiO2-B produces CO at a rate of 58 µmol·h−1·g−1 with CO selectivity of 96.3% under visible light irradiation, which is 2 and 19 times greater than those of alone TiO2-B and SnS2, respectively. Finally, a plausible photocatalytic mechanism on SnS2/TiO2-B was proposed that the electron transfer between TiO2 and SnS2 follows the Z-scheme mode. Our results present an effective way to gain highly efficient TiO2 based photocatalysts for CO2 reduction by combining different modification methods of TiO2 and make full use of the synergistic effects.

Style APA, Harvard, Vancouver, ISO itp.

22

WANG, X. H., M. ZHANG, B. S. DU i S. LI. "MICROSTRUCTURE AND WEAR PROPERTIES OF LASER CLAD TiB2 + TiC/Fe COMPOSITE COATING". Surface Review and Letters 19, nr 05 (październik 2012): 1250052. http://dx.doi.org/10.1142/s0218625x12500527.

Pełny tekst źródła

Streszczenie:

Iron-based composite coatings reinforced with TiB2–TiC multiple ceramic have been fabricated from a precursor of B4C , TiO2 and Al powders by laser cladding. The effect of TiO2 and Al on the microstructure and wear properties of the coatings was investigated. The results showed that the volume fraction, type and size of the reinforcements were influenced by the content of TiO2 and Al . TiB2 and TiC were evenly distributed in the coating; however, most of Al2O3 were ejected from the coatings, only few of them retained in the coating acting as nucleation core of reinforcement or inclusion. The microhardness and wear resistance of the coatings were improved, whereas the friction coefficients of the coatings were considerably lower than that of substrate.

Style APA, Harvard, Vancouver, ISO itp.

23

Sundaram, V., K. V. Logan i R. F. Speyer. "Aluminothermic reaction path in the synthesis of a TiB2–Al2O3 composite". Journal of Materials Research 12, nr 7 (lipiec 1997): 1681–84. http://dx.doi.org/10.1557/jmr.1997.0230.

Pełny tekst źródła

Streszczenie:

Differential thermal analysis, in air and argon, in concert with x-ray diffraction, was performed on 2- and 3-component mixtures of Al, B2O3, and TiO2, to foster an understanding of the reaction path involved in the TiB2-forming thermite reaction. In argon, aluminum reacted with B2O3 to form elemental boron, and reacted with TiO2 to form AlTi3. These two products reacted just after boron was made available at ∼1060 °C to form TiB2. Formation of Al18B4O33 by reaction between B2O3 reactant and Al2O3 product attenuated the yield of TiB2, but facilitated its formation by extraction of Al2O3 reaction barriers.

Style APA, Harvard, Vancouver, ISO itp.

24

Du, Yi-en, Xianjun Niu, Wanxi Li, Jing An, Yufang Liu, Yongqiang Chen, Pengfei Wang, Xiaojing Yang i Qi Feng. "Microwave-Assisted Synthesis of High-Energy Faceted TiO2 Nanocrystals Derived from Exfoliated Porous Metatitanic Acid Nanosheets with Improved Photocatalytic and Photovoltaic Performance". Materials 12, nr 21 (4.11.2019): 3614. http://dx.doi.org/10.3390/ma12213614.

Pełny tekst źródła

Streszczenie:

A facile one-pot microwave-assisted hydrothermal synthesis of rutile TiO2 quadrangular prisms with dominant {110} facets, anatase TiO2 nanorods and square nanoprisms with co-exposed {101}/[111] facets, anatase TiO2 nanorhombuses with co-exposed {101}/{010} facets, and anatase TiO2 nanospindles with dominant {010} facets were reported through the use of exfoliated porous metatitanic acid nanosheets as a precursor. The nanostructures and the formation reaction mechanism of the obtained rutile and anatase TiO2 nanocrystals from the delaminated nanosheets were investigated. The transformation from the exfoliated metatitanic nanosheets with distorted hexagonal cavities to TiO2 nanocrystals involved a dissolution reaction of the nanosheets, nucleation of the primary [TiO6]8− monomers, and the growth of rutile-type and anatase-type TiO2 nuclei during the microwave-assisted hydrothermal reaction. In addition, the photocatalytic activities of the as-prepared anatase nanocrystals were evaluated through the photocatalytic degradation of typical carcinogenic and mutagenic methyl orange (MO) under UV-light irradiation at a normal temperature and pressure. Furthermore, the dye-sensitized solar cell (DSSC) performance of the synthesized anatase TiO2 nanocrystals with various morphologies and crystal facets was also characterized. The {101}/[111]-faceted pH2.5-T175 nanocrystal showed the highest photocatalytic and photovoltaic performance compared to the other TiO2 samples, which could be attributed mainly to its minimum particle size and maximum specific surface area.

Style APA, Harvard, Vancouver, ISO itp.

25

Shi, Qingying, Chen Yang, Bingjie Zhang, Dongxiao Chen, Fuping Lu i Huabing Zhao. "Bacillus coagulans Alleviates Intestinal Damage Induced by TiO2 Nanoparticles in Mice on a High-Fat Diet". Foods 11, nr 21 (26.10.2022): 3368. http://dx.doi.org/10.3390/foods11213368.

Pełny tekst źródła

Streszczenie:

Titanium dioxide nanoparticles (TiO2 NPs) are generally added in considerable amounts to food as a food additive. Oral exposure to TiO2 NPs could induce intestinal damage, especially in obese individuals with a high-fat diet. The probiotic Bacillus coagulans (B. coagulans) exhibits good resistance in the gastrointestinal system and is beneficial to intestinal health. In this study, B. coagulans was used to treat intestinal damage caused by TiO2 NPs in high-fat-diet mice via two intervention methods: administration of TiO2 NPs and B. coagulans simultaneously and administration of TiO2 NPs followed by that of B. coagulans. The intervention with B. coagulans was found to reduce the inflammatory response and oxidative stress. A 16S rDNA sequencing analysis revealed that B. coagulans had increased the diversity of gut microbiota and optimized the composition of gut microbiota. Fecal metabolomics analysis indicated that B. coagulans had restored the homeostasis of sphingolipids and amino acid metabolism. The intervention strategy of administering TiO2 NPs followed by B. coagulans was found to be more effective. In conclusion, B. coagulans could alleviate intestinal damage induced by TiO2 NPs in high-fat-diet mice TiO2B. coagulans. Our results suggest a new avenue for interventions against intestinal damage induced by TiO2 NPs.

Style APA, Harvard, Vancouver, ISO itp.

26

Niyomwas, Sutham. "Synthesis of TiO₂-B₂O₃-Al Based Porous Composites". Advanced Materials Research 626 (grudzień 2012): 1–5. http://dx.doi.org/10.4028/www.scientific.net/amr.626.1.

Pełny tekst źródła

Streszczenie:

The TiB2-Al2O3 porous composites were obtained in situ by self-propagating high temperature synthesis (SHS) of TiO2-B2O3-Al System. The reaction was carried out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The effects of increasing aluminum mole ratio to the precursor mixture of TiO2, B2O3 and Al were investigated. XRD and SEM analyses indicate complete reaction of precursors to yield TiB2-Al2O3 as product composite

Style APA, Harvard, Vancouver, ISO itp.

27

Zhao, Zhiyuan, Xiaobo Duan, Lei Zhang, Zhiwei Che, Kun Wang, Bin Zheng i Xiaogang Wang. "Elevated electrochemical performances enabled by a core–shell titanium hydride coated separator in lithium–sulphur batteries". RSC Advances 11, nr 49 (2021): 30755–62. http://dx.doi.org/10.1039/d1ra04281e.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

28

Hasmin, Hudya Fitra, i Elvaswer Elvaswer. "Karakterisasi Arus-Tegangan Sensor Gas Hidrogen dari Bahan Komposit TiO2-SrCO3". Jurnal Fisika Unand 8, nr 1 (2.01.2019): 26–33. http://dx.doi.org/10.25077/jfu.8.1.26-33.2019.

Pełny tekst źródła

Streszczenie:

Telah dilakukan karakterisasi sensor gas hidrogen berupa pelet dengan bahan komposit TiO2-SrCO3. Pelet sensor gas hidrogen dibuat dengan komposisi yang berbeda untuk setiap sampel. Proses pembuatan sensor gas hidrogen diawali dengan pencampuran bahan, kalsinasi pada temperatur 500°C selama 4 jam, penggerusan, kompaksi dan sintering pada temperatur 700°C selama 4 jam dengan mengunakan metode reaksi dalam keadaan padat. Sensor gas hidrogen diuji pada temperatur ruang dengan pengukuran karakteristik I-V, nilai sensitivitas, selektivitas, konduktivitas, waktu respon, dan karakterisasi XRD. Berdasarkan pengukuran karakteristik I-V diperoleh bahwa bahan dengan komposisi 70% mol TiO2 + 30% mol SrCO3 memiliki sensitivitas dan selektivitas tertinggi. Nilai sensitivitas yang diperoleh yaitu 4,4 pada tegangan 24 volt, sedangkan nilai selektivitas yaitu 3,26 pada tegangan 24 volt. Nilai konduktivitas tertinggi dimiliki bahan dengan komposisi 70% mol TiO2 + 30% mol SrCO3 yaitu 8.44 x 10-4/Ωm pada lingkungan hidrogen. Waktu respon bahan dengan komposisi 70% mol TiO2 + 30% mol SrCO3 terhadap gas hidrogen adalah 43 s dan waktu respon terhadap gas oksigen adalah 49 s pada tegangan 24 volt. Hasil XRD menunjukkan ukuran kristal 100% TiO2 yaitu 149,01 nm, ukuran kristal 100% SrCO3 yaitu 127,128 nm, dan ukuran kristal 70% TiO2 + 30% SrCO3 adalah 159, 315 nm. Campuran TiO2 didoping SrCO3 telah terbentuk senyawa baru yaitu Sr2(TiO4). Kata kunci: sensor, TiO2-SrCO3, gas hidrogen, sensitivitas, waktu respon

Style APA, Harvard, Vancouver, ISO itp.

29

Lin, Wen Churng, Rui Liu i Wein Duo Yang. "Effect of Iron (III)-Doping on the Photocatalytic Activity of Titanium Dioxide Catalysts for Methylene Blue Degradation". Applied Mechanics and Materials 117-119 (październik 2011): 1088–91. http://dx.doi.org/10.4028/www.scientific.net/amm.117-119.1088.

Pełny tekst źródła

Streszczenie:

Iron-doped TiO2 photocatalyst powders were prepared by the sol–gel method and characterized by Brunauer–Emmett–Teller (BET)-specific surface area, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Ultraviolet–Visible (UV-Vis) spectroscopy. Fe3+ doping in the TiO2 decreases the crystal grain size, increases the specific surface areas of powders, extends the absorption to visible light regions (400~500 nm), and lowers the photocatalytic activity for methylene blue (MB) degradation under UV irradiation. The photocatalytic degradation of MB in water was investigated as a function of the Fe3+ content in TiO2. It was found that under the irradiation of visible light, a small amount of Fe3+ dopant in TiO22 powders could obviously enhance the photocatalytic activity. When the Fe3+ content was in the range of 0.03–0.1 mol%, the photocatalytic activity of the samples was higher than that of undoped TiO2. Appropriate content of Fe-doping is an effective means to improve the photocatalytic activity of TiO2 for MB degradation under visible light irradiation.

Style APA, Harvard, Vancouver, ISO itp.

30

Welham, Nicholas J. "Formation of Nanometric TiB2 from TiO2". Journal of the American Ceramic Society 83, nr 5 (21.12.2004): 1290–92. http://dx.doi.org/10.1111/j.1151-2916.2000.tb01372.x.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

31

Zhao, Shu Mao, i Ling Ran Zhao. "Mechanical Properties of Hot-Pressed B4C-TiB2 Composites Synthesized from B4C-TiO2 and B4C-TiC". Key Engineering Materials 902 (29.10.2021): 81–86. http://dx.doi.org/10.4028/www.scientific.net/kem.902.81.

Pełny tekst źródła

Streszczenie:

In this study, B4C-TiB2 ceramic composites were manufactured by hot pressing method. The raw materials for the in-situ synthesis of TiB2 were TiO2 and TiC. After being sintered at 1900°C for 60min under a pressure of 30MPa, compact composites samples with a TiB2 volume fraction range from 0 to 11.05% were prepared. The relative density, fracture toughness and flexural strength of different sample were tested. Microstructures on the fracture surface were studied by SEM. The result shows that B4C-TiB2 ceramic composites sintered from B4C-TiC had a better mechanical property than the one sintered from B4C-TiO2. When the content of TiB2 (reacted from TiC) was 11.05vol.%, the strength and toughness of B4C-TiB2 ceramics can reach 598MPa and 6.45MPa·m1/2. The toughening mechanisms of B4C-TiB2 composites include micro-crack toughening and energy consumption by the pulling out process of second phase.

Style APA, Harvard, Vancouver, ISO itp.

32

Shi, Zhuo, Lianlai Sun, Kun Liu, Yingying Zhang, Weiyuan Wang i Wei Jiang. "Two-Step Hydrothermal Synthesis of Well-Dispersed (Na0.5Bi0.5)TiO3 Spherical Powders". Journal of Nanomaterials 2019 (24.02.2019): 1–8. http://dx.doi.org/10.1155/2019/4768069.

Pełny tekst źródła

Streszczenie:

(Na0.5Bi0.5)TiO3 (NBT) powders that have well-dispersed, uniform particle size and well-developed spherical shape were successfully prepared by a two-step hydrothermal synthesis method. Nanosized TiO2 powders were firstly synthesized by a hydrothermal method, and then the TiO2 particles are used as a raw material to synthesize NBT powders. It was found that by using the TiO2 nanoparticles as Ti source, the well-dispersed spherical NBT powders with about 200 nm in size could be obtained at 200°C for 4 h with a low mineralizer concentration of 6 mol/L NaOH in the second step. The formation of spherical NBT powders can be explained by first generating nuclei on the surface of TiO2 nanoparticles via in situ crystallization mechanism and then crystal growing and agglomerating by dissolution-recrystallization mechanism.

Style APA, Harvard, Vancouver, ISO itp.

33

Wang, Guo Feng, Ji Hong Zhang, Chunping Zhang i Kai Feng Zhang. "Densification and Mechanical Properties of B₄C Based Composites Sintered by Reaction Hot-Pressing". Key Engineering Materials 434-435 (marzec 2010): 24–27. http://dx.doi.org/10.4028/www.scientific.net/kem.434-435.24.

Pełny tekst źródła

Streszczenie:

Boron carbide (B4C) possesses unique physical and thermal properties. In this paper, B4C based composites toughened by TiB2 were fabricated by in-situ reaction sintering with the original microcrystalline powders B4C, TiO2 and glucose. The influences of sintering temperature and content of TiO2 on the sintering behavior and mechanical properties were investigated. (TiB2, Al2O3)/B4C and (TiB2,SiC)/B4C composites with almost fully dense were fabricated by using additives of Al2O3 and Si powders and sintering at 1950°C and 1900°C, the fracture toughness of composites reach to 7.09 and 6.35 MPa•m1/2 respectively. The analysis of microstructure shows that the main toughen mechanism is the crack deflection due to the existence of residual stress.

Style APA, Harvard, Vancouver, ISO itp.

34

Kang, Shin Hyuk, Beom Seob Kim i Deug Joong Kim. "The Atmosphere Effect on Synthesis of TiB₂ Particles by Carbothermal Reduction". Materials Science Forum 534-536 (styczeń 2007): 145–48. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.145.

Pełny tekst źródła

Streszczenie:

The carbothermal reduction synthesis process of titanium diboride (TiB2) particles was studied. In the synthesis of TiB2 using carbothermal reduction from a mixture of TiO2, B2O3 and carbon, solid-solid reactions occur. TiO2 particles rapidly react with carbon to TiC, which then reacts with boron oxide and carbon to TiB2. In the vacuum condition, TiB2 particles were formed within 10 minutes at temperature of 1300oC. It seems that a high exothermic reaction eventually results in the increase of reaction rate. In flowing argon atmosphere, TiB2 particles were formed at temperature of 1550oC after a reaction of 0 minute and it showed a finer particle size than that in the vacuum condition. This is attributed to the faster heat elimination due to the flowing argon. In high atmospheric pressure of argon gas such as 20 atm in reaction or cooling state, the synthesized TiB2 particles shows a mixture of diverse sized particles.

Style APA, Harvard, Vancouver, ISO itp.

35

Yeh, Chun-Liang, i Fu-You Zheng. "Formation of TiB2–MgAl2O4 Composites by SHS Metallurgy". Materials 16, nr 4 (15.02.2023): 1615. http://dx.doi.org/10.3390/ma16041615.

Pełny tekst źródła

Streszczenie:

TiB2–MgAl2O4 composites were fabricated by combustion synthesis involving metallothermic reduction reactions. Thermite reagents contained Al and Mg as dual reductants and TiO2 or B2O3 as the oxidant. The reactant mixtures also comprised elemental Ti and boron, as well as a small amount of Al2O3 or MgO to serve as the combustion moderator. Four reaction systems were conducted and all of them were exothermic enough to proceed in the mode of self-propagating high-temperature synthesis (SHS). The reaction based on B2O3/Al/Mg thermite and diluted with MgO was the most exothermic, while that containing TiO2/Al/Mg thermite and Al2O3 as the diluent was the least. Depending on different thermites and diluents, the combustion front temperatures in a range from 1320 to 1720 °C, and combustion wave velocity from 3.9 to 5.7 mm/s were measured. The XRD spectra confirmed in situ formation of TiB2 and MgAl2O4. It is believed that MgAl2O4 was synthesized through a combination reaction between Al2O3 and MgO, both of which can be totally or partially produced from the metallothermic reduction of B2O3 or TiO2. The microstructure of the TiB2–MgAl2O4 composite exhibited fine TiB2 crystals surrounded by large densified MgAl2O4 grains. This study demonstrated an energy-saving and efficient route for fabricating MgAl2O4-containing composites.

Style APA, Harvard, Vancouver, ISO itp.

36

Hui, Yang, Zhang Jiaqi i He Huan. "Preparation of carbon nanotubes/TiO₂-polyvinylidene fluoride nanocomposites and composite films". Journal of Physics: Conference Series 2263, nr 1 (1.04.2022): 012001. http://dx.doi.org/10.1088/1742-6596/2263/1/012001.

Pełny tekst źródła

Streszczenie:

Abstract In this paper, PVDF membrane was discussed, many modified materials were found from the shortage of materials, and finally carbon nanotubes/TiO2 hybrid materials were synthesized. The preparation methods and synthesis conditions of carbon nanotubes/TiO2-polyvinylidene fluoride nano composite ultrafiltration membrane were studied, and the advanced membrane treatment technology was prospected. Secondly, multi-walled carbon nanotubes/Ti02 hybrid materials were synthesized by hydrothermal method and sol-gel method.

Style APA, Harvard, Vancouver, ISO itp.

37

Mironyuk, Ivan, Igor Mykytyn i Hanna Vasylyeva. "Structural and morphological properties of titanium dioxide nanoparticles dopped by Boron atoms". Physics and Chemistry of Solid State 23, nr 3 (19.09.2022): 542–49. http://dx.doi.org/10.15330/pcss.23.3.542-549.

Pełny tekst źródła

Streszczenie:

The phase composition and morphology of boron-containing TiO2 nanoparticles obtained by the sol-gel method were investigated. The solution of titanium aqua complex [Ti (OH2)6]3+‧3Cl- was used as a precursor. Borate acid Н3ВО3 (promoter of the formation of rutile) was used as a modified reagent. A single-phase rutile TiO2 was obtained at a concentration of borate acid in the reaction mixture, which causes the formation of a 0.5В-TiO2 sample. The particles of 0.5В-TiO2 samples were in the villi-form, with a diameter of 0.8-1.2 nm, and a length of 16-24 nm. With an increase of the Н3ВО3 concentration in the reaction mixture, synthesized oxide materials (samples of 1.0В-TiO2 and 1.5В-TiO2) contain 70 % and 57% of anatase respectively, in addition to rutile phase. Titanium-borate monodentate molecules Ti(OH)3OB(OH)2‧2Н2О were formed during the synthesis of the 0.5B-TiO2 rutile sample. The interatomic distance of Ti-O in these particles is commensurate with the average length of the Ti-O – bond of TiO6 rutile octahedra. During the polycondensation process, the distance of the Ti-O molecule-promoter was reproduced as a pattern in the following octahedra of rutile crystals. Two types of titanium-borate molecules are formed in the reaction medium, during the synthesis of 1.0В-TiO2 and 1.5В-TiO2 samples. Molecules with a bidentate mononuclear structure Ті(ОН)2О2ВОН‧2Н2О in which the interatomic distance of Ti-O is commensurate with the average length of the Ti-O –bond in the anatase octahedra was formed. Therefore, titanium-borate molecules of the second type act as a promoter of the formation of the TiO2 anatase phase.

Style APA, Harvard, Vancouver, ISO itp.

38

Cherniakova, Iryna, Svitlana Zdolnik i Vitaly Petrovsky. "Effect of cooling rate after hot pressing on electrical conductivity of Si3N4-ceramics with TiO2 and TiH2 additives". Processing and Application of Ceramics 4, nr 2 (2010): 63–68. http://dx.doi.org/10.2298/pac1002063c.

Pełny tekst źródła

Streszczenie:

It has been established that cooling rate after hot pressing has influence on microstructure, electrical conductivity and charge storage in Si3N4 ceramics with TiO2 and TiH2 additives, which can be used as substrates for the large capacity micro assemblies by Flip-Chip technology. It was shown that the critical cooling rate is 30?C/min for the Si3N4-TiO2 and 50?C/min for the Si3N4-TiH2 ceramics. Electrical conductivity is structurally sensitive property, strongly connected with evolution of Si3N4 microstructure. The best properties are typical for Si3N4 ceramics characterized by mono-trap state level with the activation energy of about 0.8 eV, obtained at the characteristic cooling rates. .

Style APA, Harvard, Vancouver, ISO itp.

39

Yeh, Chun-Liang, i Chen Chen. "In Situ Formation of Titanium Diboride/Magnesium Titanate Composites by Magnesiothermic-Based Combustion Synthesis". Processes 12, nr 3 (24.02.2024): 459. http://dx.doi.org/10.3390/pr12030459.

Pełny tekst źródła

Streszczenie:

In situ formation of TiB2–Mg2TiO4 composites was investigated by combustion synthesis involving the solid-state reaction of Ti with boron and magnesiothermic reduction of B2O3. Certain amounts of MgO and TiO2 were added to the reactant mixtures of Ti/B/Mg/B2O3 to act as the moderator of highly exothermic combustion and a portion of the precursors to form Mg2TiO4. Two combustion systems were designed to ensure that synthesis reactions were sufficiently energetic to carry on self-sustainably, that is, in the mode of self-propagating high-temperature synthesis (SHS). Consistent with thermodynamic analyses, experimental results indicated that the increase in pre-added MgO and TiO2 decreased the combustion temperature and propagation velocity of the flame front. MgO was shown to have a stronger dilution effect on combustion exothermicity than TiO2, because the extent of magnesiothermic reduction of B2O3 was reduced in the MgO-added samples. In situ formation of the TiB2–Mg2TiO4 composite was achieved from both types of samples. It is believed that, in the course of the SHS progression, Mg2TiO4 was produced through a combination reaction between MgO and TiO2, both of which were entirely or partially generated from the metallothermic reduction of B2O3. The microstructure of the products exhibited fine TiB2 crystals in the shape of short rods and thin platelets that existed within the gaps of Mg2AlO4 grains. Both constituent phases were well distributed. A novel and efficient synthesis route, which is energy- and time-saving, for producing Mg2TiO4-containing composites was demonstrated.

Style APA, Harvard, Vancouver, ISO itp.

40

Shan, L. L., R. M. Fan, Y. Sun, F. P. Zhang, G. L. Zhang i G. Q. Qin. "Oxygen Dependence of Formation, Electronic State Transition, and Spin Polarization for Anatase TiO2: A Comprehensive Study". Advances in Condensed Matter Physics 2022 (11.04.2022): 1–14. http://dx.doi.org/10.1155/2022/4709525.

Pełny tekst źródła

Streszczenie:

The stability, geometry, microstructure, and specie combination together with the electronic states of the anatase TiO2 with oxygen defect content of 0%, 3.125%, 6.25%, and 12.5% have been intensively studied within the framework of the density functional theory method. The results show that the TiO2 with an oxygen defect is not as stable as intrinsic TiO2. The compound formation enthalpy Ef and the oxygen defect formation energy value tend to be larger for a higher defect content, and the oxygen defect gets harder to be formed. The bonds within the TiO6 polyhedron are different and not geometrically symmetrical. The bond strengths show distinct diversity, and the primitive cell of anatase TiO2 show spatial expansion when there are oxygen defects. All bands moved down to the low energy region, and two impurity energy band levels emerged for the anatase TiO2 with oxygen defect. The energy band gap is decreased from 3.085 eV to 1.165 eV, 1.0015 eV, and 0.43 eV. There are generally 7 peaks for the spin density of states function, corresponding to their 5 main bands. For the anatase TiO2 with an oxygen defect content of 12.5%, the spin density of states functions are not horizontal ordinate symmetrical near −1.12 eV and 0.31 eV. They are formed by oxygen defect energy levels, which is the result of the Ti d and O p state electron polarization. Transitions from weak paramagnetic to antiferromagnetic are found for the anatase TiO2 with oxygen defect.

Style APA, Harvard, Vancouver, ISO itp.

41

Furqonita, Annisa, Anthoni B. Aritonang i M. Agus Wibowo. "SINTESIS TiO2 TERDOPING Bi3+ DAN UJI AKTIVITAS FOTOKATALISIS ANTIBAKTERI E.coli DENGAN BANTUAN SINAR TAMPAK (SYNTHESIS OF Bi3+ DOPED TiO2 AND PHOTOCATALYSIS ACTIVITY TEST OF E.coli ANTIBACTERIA UNDER VISIBLE IRRADIATION)". Indonesian Journal of Pure and Applied Chemistry 4, nr 2 (31.08.2021): 69. http://dx.doi.org/10.26418/indonesian.v4i2.46976.

Pełny tekst źródła

Streszczenie:

The synthesis of Bi3+ doped TiO2 was carried out using the sol-gel method with the precursor solution of titanium tetraisopropoxide (TTiP). Bi3+ cation dopant is done to reduce the energy of the TiO2 band gap so that it can be active in the visible light region. The synthesized Bi(III) –TiO2 photocatalyst was characterized using DRS UV-Vis, FTIR, and EDX. The results of the DRS UV-Vis analysis showed that 1% Bi(III) –TiO2 photocatalyst had a bandgap energy of 2.79 eV or equivalent to a wavelength of 469.97 nm. Infrared spectra show that there is a unique absorption at the wave number 956,56 cm-1 which is the absorption of the vibration Bi-O-Ti group. Photocatalyst Bi(III) -TiO2 was then tested for antibacterial activity against E. coli in polluted water. The activity test was carried out using the turbidimetric method by UV-vis spectrophotometry. The results of the activity test for 120 minutes with the help of visible light showed that the photocatalyst Bi(III) –TiO21% had the best antibacterial activity. The decrease in the number of E. coli in the water reached 48.54%.

Style APA, Harvard, Vancouver, ISO itp.

42

Peng, Gow-Weng, Shou-Kang Chen i Hok-Shing Liu. "Infrared Absorption Spectra and Their Correlation with the Ti-O Bond Length Variations for TiO2 (Rutile), Na-Titanates, and Na-Titanosilicate (Natisite, Na2TiOSiO4)". Applied Spectroscopy 49, nr 11 (listopad 1995): 1646–51. http://dx.doi.org/10.1366/0003702953965786.

Pełny tekst źródła

Streszczenie:

The mid-infrared absorption spectra (400–1200 cm−1) of four TiO2-bearing crystalline solids, in the form of rutile (TiO2), Na-titanates (Na2Ti6O13/ Na2Ti3O7), and natisite (Na2TiOSiO4), are presented, providing a clear illustration of their differences in IR band structure (band pattern). Two sharp characteristic peaks of IR absorption bands of natisite have been noted at 725 and 624 cm−1, representing the internal vibration modes of TiO5 (normal) and SiO4 structural units, respectively, and obtainable by comparison with that of Ca-titanosilicate (CaTiOSiO4), NTS glass (Na2O-TiO2-SiO2), and low-cristobalite (SiO2). The tested series of TiO2-bearing crystalline solids has been helpful in presenting a case study in support for the generalization of IR spectra/structure correlations, showing that vibrational spectroscopy can be useful for understanding the crystal chemistry of crystalline solids in terms of the geometric setting of molecular structural units and chemical bonds. It has been qualitatively demonstrated that the Ti-O bond length variations may be broadly correlated with the complexity of IR absorption bands of four TiO2-bearing solids having great diversity in both chemical composition and crystalline structure.

Style APA, Harvard, Vancouver, ISO itp.

43

Mansurov, Z. A., D. S. Abdulkarimova, O. Odawara, A. Gubarevich, A. S. Rogachev, N. F. Shkodich i N. N. Kochetov. "Peculiarities of Self-Propagating High-Temperature Synthesis and Structure Formation of TiB2-Al2O3 and CrB2-Al2O3 Composites". Eurasian Chemico-Technological Journal 13, nr 3-4 (22.12.2011): 161. http://dx.doi.org/10.18321/ectj.80.

Pełny tekst źródła

Streszczenie:

Preparation of TiB2-Al2O3 and CrB2-Al2O3 composites with a broad range of phase composition was conducted by self-propagating high-temperature synthesis (SHS) involving reaction of different types. The formation of fibrous crystals of aluminum oxide with length of about 10-25 microns and with diameter of 200-500 nm at self-propagating high-temperature synthesis in the system 2B2O3-Cr2O3-6A1 was established. Thermite mixtures of Al-TiO2 and Al-TiO2-B2O3 were incorporated with the Ti-B combustion system to produce the composites of TiB2-Al2O3, within which the increase of the thermite mixture for a higher content of Al2O3 decreased the reaction temperature and combustion wave velocity. This implies that the thermite reaction of Al with TiO2 reduces the exothermicity of the overall SHS process. It was found that adoption of B2O3 as one of the thermite reagents improved the product formation effectively. For investigate the combustion wave in 0.75TiO2-0.25Ti-2B-Al system the «quenching» method was used. The XRD analysis shows that the final products containing diborides and aluminium oxide.

Style APA, Harvard, Vancouver, ISO itp.

44

Yan, Yong Jie, Zheng Ren Huang, Shao Ming Dong i Dong Liang Jiang. "Carbothermal Preparation of Ultra-Fine TiB₂ Powders Using Solution-Derived Precursors via Sol-Gel Method". Key Engineering Materials 336-338 (kwiecień 2007): 944–47. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.944.

Pełny tekst źródła

Streszczenie:

Ultra-fine titanium diboride (TiB2) powders have been prepared by carbothermal reduction reactions in TiO2-B2O3-C system using tetrabutyl titanate, boric acid and phenolic resin as the solution-derived precursors. The reactions were substantially completed at relatively lower temperature (<1400°C) and the resulting products had a smaller average crystallite size (< 200 nm). However, below 1100°C, titanium carbide was the predominant phase and the relative content decreased with the rise of temperature. The thermodynamic change in TiO2-B2O3-C system was mainly studied by TG-DTA and the mechanism of synthesis of TiB2 was discussed. The crystallite size and morphology of the synthesized powders were characterized by SEM and TEM.

Style APA, Harvard, Vancouver, ISO itp.

45

Квеглис, Л. И., А. В. Павлов i А. В. Джес. "ИССЛЕДОВАНИЕ ВЛИЯНИЯ НАНОРАЗМЕРНЫХ ЧАСТИЦ TiO2 НА ФИЗИКО-МЕХАНИЧЕСКИЕ СВОЙСТВА, СТРУКТУРУ И ФАЗОВЫЙ СОСТАВ (ВеО + TiO2)-КЕРАМИКИ". Фундаментальные проблемы современного материаловедения, nr 1 (31.03.2022): 41–49. http://dx.doi.org/10.25712/astu.1811-1416.2022.01.005.

Pełny tekst źródła

Streszczenie:

В настоящем исследовании представлены результаты влияния количества нано размерных частиц TiO2 (0,1-2,0 мас.%) и температуры обжига на физико-механические свойства, структуру и фазовый состав оксидно-бериллиевой керамики состава (ВеО + TiO2) изготовленной из порошков микронного размера. Показано, что присутствие наночастиц TiO2 способствует увеличению плотности спеченной керамики. Данный эффект достигается вследствие взаимопроникновения фаз ВеО – TiO2 и увеличения дефектности структуры. Понижение энергии активации процессов обмена мест в зоне границы зерен может быть объяснено связью между диффузией и дефектами строения решетки. Диффузия вдоль границы зерен происходит быстрее, чем в ненарушенной. Присутствие наночастиц также способствует самозалечиванию микропор, что может быть объяснено блокированием наночастицами определенной доли границ раздела между частицами ВеО и созданием диффузионного барьера. Инжекция вакансий внутрь кристалла, повышает свободную энергию системы, делает термодинамически невыгодным его рост, в определенном интервале размеров. Как показано в настоящем исследовании, повышение температуры спекания керамики, способствует трансформации кристаллической структуры TiO2в более проводящую Ti3O5 с орторомбической структурой. Возникновение электропроводящей фазы, как правило, сопровождается поглощением электромагнитного излучения. Синтезированная керамика актуальна для нужд радио-электронной промышленности: электровакуумные приборы СВЧ – ЭВП, усилители, лампы бегущей и обратной волны, клистроны, клистроды, гироприборы; твердотельные приборы СВЧ; модули СВЧ; комплексированные изделия СВЧ с применением в своем составе ЭВП СВЧ, твердотельных дискретных приборов и модулей СВЧ.

Style APA, Harvard, Vancouver, ISO itp.

46

Koivisto, Antti Joonas, Benedetta Del Secco, Sara Trabucco, Alessia Nicosia, Fabrizio Ravegnani, Marko Altin, Joan Cabellos i in. "Quantifying Emission Factors and Setting Conditions of Use According to ECHA Chapter R.14 for a Spray Process Designed for Nanocoatings—A Case Study". Nanomaterials 12, nr 4 (10.02.2022): 596. http://dx.doi.org/10.3390/nano12040596.

Pełny tekst źródła

Streszczenie:

Spray coatings’ emissions impact to the environmental and occupational exposure were studied in a pilot-plant. Concentrations were measured inside the spray chamber and at the work room in Near-Field (NF) and Far-Field (FF) and mass flows were analyzed using a mechanistic model. The coating was performed in a ventilated chamber by spraying titanium dioxide doped with nitrogen (TiO2N) and silver capped by hydroxyethylcellulose (Ag-HEC) nanoparticles (NPs). Process emission rates to workplace, air, and outdoor air were characterized according to process parameters, which were used to assess emission factors. Full-scale production exposure potential was estimated under reasonable worst-case (RWC) conditions. The measured TiO2-N and Ag-HEC concentrations were 40.9 TiO2-μg/m3 and 0.4 Ag-μg/m3 at NF (total fraction). Under simulated RWC conditions with precautionary emission rate estimates, the worker’s 95th percentile 8-h exposure was ≤171 TiO2 and ≤1.9 Ag-μg/m3 (total fraction). Environmental emissions via local ventilation (LEV) exhaust were ca. 35 and 140 mg-NP/g-NP, for TiO2-N and Ag-HEC, respectively. Under current situation, the exposure was adequately controlled. However, under full scale production with continuous process workers exposure should be evaluated with personal sampling if recommended occupational exposure levels for nanosized TiO2 and Ag are followed for risk management.

Style APA, Harvard, Vancouver, ISO itp.

47

Hatimah, Husnul. "Pengaruh Ion Hg(II) Terhadap Efektivitas Fotoreduksi Ion Cu(II) Terkatalisis TiO2 dalam Limbah Cair Industri Kerajinan Perak di Desa Ungga Kec. Praya Lombok Tengah". Hydrogen: Jurnal Kependidikan Kimia 6, nr 1 (4.01.2019): 75. http://dx.doi.org/10.33394/hjkk.v6i1.1602.

Pełny tekst źródła

Streszczenie:

In this study a study of the effect of TiO2 photocatalysts and Hg (II) ions in thewastewater of the silver industry in Ungga Village, Kec. PrayaKab. CentralLombok to the effectiveness of Cu (II) photoreduction which is catalyzed byTiO2. The photoreduction process is carried out by irradiating liquid wastecontaining Cu (II) and Hg (II) ions without or by adding TiO2 photocatalystpowder in a closed reactor equipped with UV light. The condition of thephotoreduction process is 50 mL of silver waste containing Cu (II) and Hg (II)with a reaction time of 24 hours and a mass of TiO2 20 mg at 10 ppm Cu (II) ionconcentration. Photoreduction results are determined based on the difference inthe concentration of Cu (II) ions with the concentration of residual Cu (II) ionsin silver waste without the addition of TiO2 photocatalysts. Furthermore, thedata obtained compared to the results of Cu (II) photoreduction catalyzed bypure TiO2 laboratory scale. The amount of metal in the mixture was determinedby the Atomic Absorption Spectrophotometry (AAS) method. The results showedthat in silver handicrafts containing Cu (II) and Hg (II) ions the addition of TiO2can increase the effectiveness of Cu (II) photoreduction from 6.57% to 33.38%,which begins with the adsorption process. Hg (II) in silver handicraft wastecauses inter-metal reduction competition so that it can reduce the effectiveness ofCu (II) ion photoreduction catalyzed by TiO2 by 9.84% when compared to thepercentage of Cu (II) ion Ti2O scale scale laboratory testing.

Style APA, Harvard, Vancouver, ISO itp.

48

Utomo, Arya Dwi Cahyo, i Muh Nur Khoiru Wihadi. "Preparation of ZnO/TiO2 Nanocomposite Sensitized Mangosteen Rind (Garcinia mangostana L) Dye for Light Harvesting Efficiency in Solar Cell". Indo. J. Chem. Res. 10, nr 2 (29.09.2022): 68–73. http://dx.doi.org/10.30598//ijcr.2022.10-ary.

Pełny tekst źródła

Streszczenie:

The preparation of ZnO/TiO2 nanocomposite is done using the sol-gel method for light harvesting in dye-sensitized solar cell (DSSC). The titanium dioxide (TiO2) compound was added with different ratios to the ZnO matrix and measured its effect on solar cells based on the DSSC system. The powder X-ray diffractions of nanocomposite revealed anatase (TiO2) and wurtzite (ZnO) phases have the highest peak at 25.26° and 36.97°, respectively. The energy gap was observed by diffuse reflectance-ultra violet (DR-UV) spectroscopy and it revealed that the optimum performance of nanocomposite was 3.16 eV for the 1:2 ratio. The optimum power efficiency was 2.4% with 3.6 cm2 active area, Voc= 788 mV and Isc=3.39 mA, respectively. The scanning electron microscope-energy dispersive X-ray (SEM-EDX) demonstrated the diversity of surface morphology depends on the ratio of TiO2 in the nanocomposite. This shows the addition of TiO2 to the ZnO matrix influenced the structure of the nanocomposite, which can be applied as DSSC electrodes.

Style APA, Harvard, Vancouver, ISO itp.

49

Mobasheri, Raouf, Abdel Aitouche, Sadegh Pourtaghi Yousefdeh i Abbas Zarenezhad Ashkezari. "Assessing the Impact of Ethanol/Biodiesel/Diesel Blends and Nanoparticle Fuel Additives on Performance and Emissions in a DI Diesel Engine with EGR Integration: An Experimental Study". Processes 11, nr 4 (19.04.2023): 1266. http://dx.doi.org/10.3390/pr11041266.

Pełny tekst źródła

Streszczenie:

In this paper, the effect of nano-particles along with EGR rates was experimentally assessed on the performance and emission of a DI diesel engine fueled by biodiesel and ethanol. For this purpose, three levels of TiO2 nanoparticles (0, 40, and 60 ppm) were added to biodiesel/diesel blends in the proportions of 0, 10, and 20% biodiesel with ethanol at levels of 0, 4, and 6%. EGR rates were used at 0, 20, and 30%. A total of 31 fuel samples with different ethanol, biodiesel, TiO2 nano-additives, and EGR rates were tested at different speeds. The equation for this combination is BxEy + EGRw + TiO2z, where x, y, w, and z are the percentages of biodiesel, ethanol, EGR, and TiO2. The results showed that the mixture of B10E4 + EGR20 + TiO260, reduced the amount of NOx, CO, and HC by 10, 12.4, and 17%. Moreover, due to the significant reduction of emissions and performance improvement, the combinatory method of EGR–TiO2 nano-additives can be used as an effective formula for diesel engines fueled with ethanol/biodiesel/diesel blends.

Style APA, Harvard, Vancouver, ISO itp.

50

Shi, Dan, Zhi Li Zhang, De Cai Li, Qi Han i Tie Peng Xing. "Preparation and Photo-Catalysis Properties of Fe₃O₄/TiO₂ Nanocomposite". Key Engineering Materials 512-515 (czerwiec 2012): 187–90. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.187.

Pełny tekst źródła

Streszczenie:

As a Kind of Most Common Used Photocatalyst, TiO2 Nanomaterials Existing Disadvantages on Low Light Energy Utilization in Visible Light Range and Difficulty on Recycle. in Our Study, Different Proportions of Fe3+ and Fe2+ Ion Were Doped with Nano-Ti02 Particles in Structure of Rutile Type through Method of Chemical Precipitation. the Result Showed that Nano-Composites Formed by TiO2 Coexist with Fe3O4, with the Average Size of the Composite Particles Nearly 20 Nm. the Photo-Catalyst Performances of the Composite Have Improved Largely, and so the Relatively Optimized Preparation Conditions Were Presented.

Style APA, Harvard, Vancouver, ISO itp.

Artykuły w czasopismach na temat „TiO2”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych