Journal articles: 'Ferrate technologies'

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Peng, Hao, Jing Guo, Gang Li, Qinzhe Cheng, Yuju Zhou, Zuohua Liu, and Changyuan Tao. "Highly efficient oxidation of chromium (III) with hydrogen peroxide in alkaline medium." Water Science and Technology 79, no. 2 (January 15, 2019): 366–74. http://dx.doi.org/10.2166/wst.2019.056.

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Abstract Many technologies have been proposed to oxidize chromium, such as roasting-water leaching technology and hydrometallurgical methods such as pressure oxidative leaching coupled with oxygen, ozone, permanganate and ferrate, but the problems associated with the high temperature, low overall resource utilization efficiency, high energy consumption, and the environmental pollution, still remain unsolved. This paper focuses on the oxidation process of chromium (III) with hydrogen peroxide (H2O2) in an alkaline medium. The effect of parameters including dosage of H2O2, dosage of NaOH, reaction time, reaction temperature and stirring rate on the oxidation efficiency of chromium were investigated. The oxidation efficiency was significantly affected by the dosage of H2O2 and NaOH, reaction time and reaction temperature took second place; last was the stirring rate. Oxidation efficiency was nearly 100% under the optimal conditions: volume ratio of H2O2 to mass of Cr2(SO4)3 of 2.4 mL/g, mass ratio of NaOH to Cr2(SO4)3 0.6 g/g, reaction time of 90 min, reaction temperature of 90 °C and stirring rate of 500 rpm.

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Thames, Hudson T., and Anuraj Theradiyil Sukumaran. "A Review of Salmonella and Campylobacter in Broiler Meat: Emerging Challenges and Food Safety Measures." Foods 9, no. 6 (June 11, 2020): 776. http://dx.doi.org/10.3390/foods9060776.

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Poultry is one of the largest sources of animal-based protein in the United States. Poultry processing has grown from a small local network of plants to nearly 500 plants nationwide. Two of the most persistent bacteria in poultry processing are Salmonella and Campylobacter. It was not until the introduction of Hazard Analysis and Critical Control Point systems in 1996 that major efforts to reduce bacterial contamination were developed. Traditionally, chlorine has been the industry standard for decontaminating chicken meat. However, antimicrobials such as peracetic acid, cetylpyridinium chloride, and acidified sodium chlorite have replaced chlorine as primary antimicrobials. Despite current interventions, the emergence of stress-tolerant and biofilm-forming Salmonella and Campylobacter is of primary concern. In an effort to offset growing tolerance from microbes, novel techniques such as cold plasma treatment, electrostatic spraying, and bacteriophage-based applications have been investigated as alternatives to conventional treatments, while new chemical antimicrobials such as Amplon and sodium ferrate are investigated as well. This review provides an overview of poultry processing in the United States, major microbes in poultry processing, current interventions, emerging issues, and emerging technologies in antimicrobial treatments.

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Wang, Ao, Chenshuo Lin, Zhen Shen, Zhigang Liu, Hang Xu, Jiapei Cheng, and Xin Wen. "Effects of Pre-Oxidation on Haloacetonitrile and Trichloronitromethane Formation during Subsequent Chlorination of Nitrogenous Organic Compounds." International Journal of Environmental Research and Public Health 17, no. 3 (February 7, 2020): 1046. http://dx.doi.org/10.3390/ijerph17031046.

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The reaction between organic matter and disinfectants leads to the formation of disinfection byproducts (DBPs) in drinking water. With the improvement of detection technology and in-depth research, more than 1000 kinds of DBPs have been detected in drinking water. Nitrogenous DBPs (N-DBPs) are more genotoxic and cytotoxic than the regulated DBPs. The main methods are enhanced coagulation, pretreatment, and depth technologies which based are on conventional technology. Amino acids (AAs) are widely found in surface waters and play an important role by providing precursors from which toxic nitrogenous disinfection by-products (N-DBPs) are generated in chlorinated drinking water. The formation of N-DBPs, including dichloroacetonitrile, trichloroacetonitrile, and trichloronitromethane (TCNM), was investigated by analyzing chlorinated water using ozone (OZ), permanganate (PM), and ferrate (Fe(VI)) pre-oxidation processes. This paper has considered the control of pre-oxidation over N-DBPs formation of AAs, OZ, PM, and Fe(VI) pre-oxidation reduced the haloacetonitrile formation in the downstream chlorination. PM pre-oxidation decreased the TCNM formation during the subsequent chlorination, while Fe(VI) pre-oxidation had no significant influence on the TCNM formation, and OZ pre-oxidation increased the formation. OZ pre-oxidation formed the lowest degree of bromine substitution during subsequent chlorination of aspartic acid in the presence of bromide. Among the three oxidants, PM pre-oxidation was expected to be the best choice for reducing the estimated genotoxicity and cytotoxicity of the sum of the measured haloacetonitriles (HANs) and TCNM without bromide. Fe(VI) pre-oxidation had the best performance in the presence of bromide.

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Węgrzyn, T., J. Piwnik, and D. Hadryś. "Acicular Ferrite in Micro Welding Technologies." Archives of Metallurgy and Materials 59, no. 2 (June 1, 2014): 581–83. http://dx.doi.org/10.2478/amm-2014-0096.

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Abstract Laser is widely applied in micro welding. Apart from that method, welding with micro-jet cooling could be treated as another important method for thin structure welding. Until that moment micro-jet technology is not very popular. An article presents actual information about innovate welding technology with micro-jet cooling in comparison with standard laser welding. There were given information about influence of both micro welding method on metallographic structure of thin steel welds. Amount of AF was tested in two cases.

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Kmita, A., A. Pribulova, M. Holtzer, P. Futas, and A. Roczniak. "Use of Specific Properties of Zinc Ferrite in Innovative Technologies." Archives of Metallurgy and Materials 61, no. 4 (December 1, 2016): 2141–46. http://dx.doi.org/10.1515/amm-2016-0289.

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Abstract Zinc ferrite ZnFe2O4 both in the micro and nano scale is widely used in various fields. The article discusses the structure of this compound and its properties in the nanoscale, which is clearly different from those which the ferrite shows in the microscale. The properties of dust generated electric arc furnace, which can contain up to 40% zinc, substantially in the form of ZnFe2O4 are disscused here. Specific properties (electric, magnetic, thermal) of zinc ferrite nanoparticles determine the very wide possibilities of their use, inter alia as catalysts, absorbents, gas sensors, and a tool to combat cancer.

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Ma, Shao Jian, Gui Fang Wang, Jin Lin Yang, Shao Juan Que, Li Qun Tang, and Jin Peng Feng. "Study on Preparation Process of Zinc Ferrite." Advanced Materials Research 201-203 (February 2011): 1736–40. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.1736.

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Zinc ferrite is usually formed during the roasting of zinc sulfide concentrate with high content of iron and reduces zinc recovery during the leaching of zinc calcine. Because it is difficult to find pure zinc ferrite in nature ore resources or in chemicals market, which impedes the investigation of the reaction characteristics of zinc ferrite and the seek of new technologies for zinc ferrite dissolution, so it is of significance to obtain relatively pure zinc ferrite for further research on zinc calcine leaching. This article investigated the preparation process of zinc ferrite based on the dissolution characteristics of a zinc calcine with 19.38% iron and put forward a method to judge the reaction end point during the leaching of zinc calcine to produce zinc ferrite. The results show that the product of zinc ferrite could be prepared through recovering the leaching residue during leaching the zinc calcine under the initial H2SO4 concentration equal to or larger than 160g/L, and that the leaching end point can be judged by comparing the experimental curve of Zn leaching with the zinc theoretical dissolvability curve.

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Sharma, Virender K., Radek Zboril, and Rajender S. Varma. "Ferrates: Greener Oxidants with Multimodal Action in Water Treatment Technologies." Accounts of Chemical Research 48, no. 2 (February 10, 2015): 182–91. http://dx.doi.org/10.1021/ar5004219.

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Kisic, Milica, Nelu Blaz, Kalman Babkovic, Andrea Maric, Goran Radosavljevic, Ljiljana Zivanov, and Mirjana Damnjanovic. "Performance analysis of a flexible polyimide based device for displacement sensing." Facta universitatis - series: Electronics and Energetics 28, no. 2 (2015): 287–96. http://dx.doi.org/10.2298/fuee1502287k.

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In this work, two variations of the displacement sensor, based on the heterogeneous integration process of traditional fabrication technologies PCB (Printed Circuit Board) and LTCC (Low Temperature Co-fired Technology) with a flexible polyimide foil are presented. The proposed sensor uses the coil as an essential part, spacer and a polyimide foil as a flexible membrane with a piece of ferrite attached to it. With the displacement of the polyimide foil, the ferrite gets closer to the coil causing an increase in its inductance and a decrease of the resonant frequency of the system (coil, ferrite and antenna). Simulation results showed that sensors with equal outer dimensions but different internal structures exhibit different performances. Two prototypes of the sensor with different ferrite dimensions are designed, fabricated and characterized. Finally, their performances are compared.

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Liu, Jie. "SLC Technologies for Ferroalloy Part Surface Modification." Advanced Materials Research 941-944 (June 2014): 2194–97. http://dx.doi.org/10.4028/www.scientific.net/amr.941-944.2194.

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Experiments on selective laser sintering of iron based alloy and nano-Al2O3 ceramic bulk materials are carried out and effect of sintering parameters on the process is analyzed systematically. A reasonable selective laser sintering technique which can be used to fabricate parts with free shape is obtained and verified with a multilayer sintering experiment. The component and the microstructure of the sintering production is tested. The influences of parameters and the amount of nano-Al2O3 on microstructure and microhardness of the sintering parts are studied. Laser sintering iron-based alloy experiments show that: microhardness has been noticeably improved. It is indicated that with the selective laser sintering technique obtained above, nano-alumina can be processed to manufacture three-dimension parts with free shape. With the addition of Al2O3 and the increase of composite parts of the grain gradually thinning, microhardness gradually improved nanocomposite parts for the microstructure of the dendrite skeleton-shaped crystal and the plane together, the internal Al2O3 dispersion organizations to strengthen the implicit crystal martensite and ferrite mixed organizations.

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Pan, An Xia. "Toughness and Internal Friction of Weld Metal Welded by High-Current MAG Welding." Advanced Materials Research 328-330 (September 2011): 1077–81. http://dx.doi.org/10.4028/www.scientific.net/amr.328-330.1077.

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Low-temperature impact test on four different kinds of weld metal welded by different technologies of high-current MAG welding was carried out in this paper. The results show that different materials and different welding parameters have different effect on impact energy. As the chemical analysis and observation from the optical microscope show that When welding material contains appropriate C, Si, Ti, fine acicular ferrite forms in it; on the contrary, crisp and thick bainite appears. Compares to acicular ferrite which has an Akv>27J at -27°C and better toughness, bainite has a poor toughness and an Akv<27J. The internal friction experiments show that there are two internal friction peaks - Snoek and SKK. The peak is clear when the microstructure is bainite, on the other side, the microstructure is acicular ferrite.

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Kolbasnikov, Nicolay G., Oleg G. Zotov, and Aleksey A. Lukyanov. "Investigation of the Operational Reliability of the Rolled Rails According to the Various Technologies." Key Engineering Materials 651-653 (July 2015): 317–21. http://dx.doi.org/10.4028/www.scientific.net/kem.651-653.317.

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Based on experimental studies of the complex mechanical properties and microstructure, as well as simulation of rails rolling modes made from different steel manufacturers are shown the main technological approaches to obtain rails with high operational reliability . Found that, under the current production technology of domestic steel rails the adjustment of the chemical composition, temperature-deformation modes of rolling and cooling speed rate of the rails is suitable for reducing the negative free ferrite influence on rails durability.

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Li, Congwei, Jialei Zhu, Zhihai Cai, Le Mei, Xiangdong Jiao, Xian Du, and Kai Wang. "Microstructure and Corrosion Resistance of Underwater Laser Cladded Duplex Stainless Steel Coating after Underwater Laser Remelting Processing." Materials 14, no. 17 (August 31, 2021): 4965. http://dx.doi.org/10.3390/ma14174965.

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Combined with the technologies of underwater local dry laser cladding (ULDLC) and underwater local dry laser remelting (ULDLR), a duplex stainless steel (DSS) coating has been made in an underwater environment. The phase composition, microstructure, chemical components and electrochemical corrosion resistance was studied. The results show that after underwater laser remelting, the phase composition of DSS coating remains unchanged and the phase transformation from Widmanstätten austenite + intragranular austenite + (211) ferrite to (110) ferrite occurred. The ULDLR process can improve the corrosion resistance of the underwater local dry laser cladded coating. The corrosion resistance of remelted coating at 3 kW is the best, the corrosion resistance of remelted coating at 1kW and 5kW is similar and the corrosion resistance of (110) ferrite phase is better than grain boundary austenite phase. The ULDLC + ULDLR process can meet the requirements of efficient underwater maintenance, forming quality control and corrosion resistance. It can also be used to repair the surface of S32101 duplex stainless steel in underwater environment.

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Hsiang, Hsing-I., Jui-Fu Chueh, and Liang-Fang Fan. "Key Technology and Materials for the Development of DC-DC Converter Module." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2015, CICMT (September 1, 2015): 000246–57. http://dx.doi.org/10.4071/cicmt-wp23.

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Portable devices are often powered by batteries and DC-DC converters are used to convert battery energy to supply power for microprocessors and integrated circuits. Portable electronic devices are required to be compact and, hence, space for converters is very limited. Therefore, the demand for integrating individual components into modules to reduce the size and increase the power density of DC-DC converters is increasing. It is important to develop a low temperature sintering NiCuZn ferrites with a superior DC-bias-superposition characteristic; the nonmagnetic materials co-fired with the magnetic NiCuZn ferrites, and the low-pressure assisted constrained sintering process for the large area NiCuZn ferrites substrates for the DC-DC converter modules. This study successfully developed the key technologies and materials for the development of DC-DC converter module. It integrated the magnetic NiCuZn ferrites with superior DC-bias superposition characteristic and nonmagnetic ferrite materials using multilayer ceramic processing and low-pressure assisted constrained sintering technologies to prepare a large area NiCuZn ferrite substrate for DC-DC converter module.

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Yue, Lu You, Zhong Fu Huang, Zhen Liang He, Man Guo Jiang, and Wei Chen. "Microstructure Evolution and Numerical Simulation of DP Steel TWBs During Warm Tensile Deformation." Advanced Materials Research 418-420 (December 2011): 1222–27. http://dx.doi.org/10.4028/www.scientific.net/amr.418-420.1222.

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The tensile tests of DP590 dual-phase steel tailor-welded blanks were carried out at different temperatures and strain rates. Quantitative analysis of metallographic was utilized to study the microstructure evolution of the base metal area and the weld zone of the tensile fracture. By combining the microstructure evolution model with the secondary development technologies of ABAQUS, the microstructure evolution of dual-phase steel tailor-welded blanks was simulated during warm tensile tests. The results show that, with the temperature increasing and strain rate decreasing, the dynamic recrystallization volume fraction of ferrite increases, and the martensite transform into equiaxed ferrite gradually. The results of microstructure simulation are in good agreement with experimental results.

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Tatarus, Alina, Claudia Maria Simionescu, Roxana Elena Scutariu, Vasile Ion Iancu, Florinela Pirvu, Diana Puiu, and Toma Galaon. "HPLC detection of synthetic dyes in residual waters from wastewater treatment using adsorption on magnetic materials." Romanian Journal of Ecology & Environmental Chemistry 2, no. 2 (October 14, 2020): 22–29. http://dx.doi.org/10.21698/rjeec.2020.203.

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Surface water contamination by synthetic dyes generates human and wildlife adverse health effects and causes photosynthesis decrease due to intense sun-light absorption of these pollutants. 50% of total discharged industrial effluents contain azo dyes. Congo Red is a benzidine based anionic azo dye that is usually employed in rubber, paper and plastic industries. Congo Red can cause eye and skin irritation and is potentially carcinogenic in nature. This study explores the development of a new HPLC method to detect synthetic dyes in residual waters coming from wastewater treatment technologies based on magnetic material adsorption. Cobalt ferrite (CoFe2O4) and chitosan-coated cobalt ferrite (CoFe2O4-Chit) prepared by a simple co-precipitation method were tested as adsorbents for Congo Red (CR). Effect of contact time, solution pH, and initial dye concentration were studied with respect to Congo Red adsorption efficiency. The adsorption experiments were performed at pH = 4.5 and 10.8. The highest value for the removal efficiency using the magnetic material of cobalt ferrite coated with chitosan (CoFe2O4-Chit) was obtained at pH 10.8.

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Lima Santos, Willian, Anne Alilma Silva Souza Ferrete, and Rosana Maria Santos Torres Marcondes. "Interactive interfaces applied to education: (re)creating a virtual learning scenario." Conjecturas 22, no. 2 (February 24, 2022): 122–36. http://dx.doi.org/10.53660/conj-634-601.

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Digital information and communication technologies (DICT), in an accelerated process of evolution, have been reconfiguring the way people live in society, improving communication, modifying culture and enhancing educational training processes. Constantly, new interfaces have emerged, promoting network interaction and, when used pedagogically, they can be combined to the educational process by allowing the creation of virtual learning scenarios. This study aims to present a proposal of learning scenario linked to the aspects of virtuality present in interfaces, considering its applicability in online contexts. This is a bibliographic research, which has used as theoretical contribution the studies of Dias (2012), Matos (2014), Barros, Romero and Moreira (2014), Perdigão and Santos (2018), Barros (2018), Piedade, Pedro and Matos (2018), Santos, Ferrete and Alves (2020), Santos and Ferrete (2021), Santos (2021), Santos, Ferrete and Alves (2021) to support the theme of Virtual Learning Scenarios, with a focus on the elements of interactivity, collaboration and information sharing. As a result, this study presents a scenario proposal that may be adapted to both online and offline contexts, through the devices and interfaces available in each educational reality.

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Kučerová, Ludmila, Hana Jirková, and Bohuslav Mašek. "Various Approaches to Accelerated Carbide Spheroidization of 54SiCr Steel." Key Engineering Materials 647 (May 2015): 3–8. http://dx.doi.org/10.4028/www.scientific.net/kem.647.3.

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Changing the lamellar morphology of pearlite to a globular morphology significantly enhances the formability of pearlite-ferrite steels. This change is conventionally achieved by soft annealing. Annealed structures possess low yield strength and excellent ductility and this ensures their good cold formability. The problems of these technologies lie not only in long processing times, but also in high energy consumption which makes the final product quite expensive. The time necessary for cementite spheroidization can be shortened by unconventional heat treatment around Ac1 temperature combined with deformation applied at various processing stages. Several processing methods were utilized for spring steel 54SiCr with ferrite-pearlite original microstructure and lamellar pearlite morphology. The hardness of this structure reached 290 HV10. Three main strategies were tested in this work, using either tensile and compression deformation with following hold applied at heating temperature, temperature cycling around AC1 temperature, or deformation cycles applied at heating temperature. First of all, various heating temperatures in the region of 680-740°C were tested to determine the most suitable heating temperature for this steel. Subsequently, the influence of the character and intensity of applied deformations on cementite spheroidization and ferrite grain refinement were investigated. Carbide morphology and distribution were determined by the means of light and scanning electron microscopy and mechanical properties were determined by hardness measurement. Spheroidized carbides evenly distributed in fine ferrite matrix were obtained after the optimization of processing parameters.

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Li, Yun Tao, Juan Ye, Ji Shun Song, Jian Zhang, and Guang Da Liu. "Formability of Tailor-Welded Blanks for Steel with Different Thickness and Materials." Materials Science Forum 704-705 (December 2011): 1504–11. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.1504.

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With the demands of environmental protection and energy conservation, increasing resources and improving environment, TWB (Tailor Weld Blank) as one of green re-manufacturing technologies will be a guiding orientation in industry. In this study, microstructure of welded joint、tensile test、fracture surface、cupping test of the TWB were carried out. Results show that the microstructure of weld is acicular ferrite and plate pearlite. The microstructure of HAZ beside SAPH440 is pearlite and grain ferrite, and the microstructure of HAZ beside DP600 is numbly pearlite and plate ferrite. The results of tensile test show that the shape of the materials after drawing is not easy to be rebounded, plastic deformation of the blanks is excellent, and the SEM of fracture morphology shows that the fracture is ductile and cleavage when the weld line parallels tensile axis. When the weld perpendicular to tensile axial, the deformation of the TWB is uneven, the plastic deformation is poor and the fracture is typical ductile rupture. The research results of the cupping test suggest that the bulging formability of the TWB is worse than that of base materials, and the bigger proportion of the thin blank in the TWB, the better bulging formability of the TWB. Introduction

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Strečková, Magdaléna, Mária Fáberová, Radovan Bureš, and Pavel Kurek. "The Preparation of Soft Magnetic Composites Based on FeSi and Ferrite Fibers." Powder Metallurgy Progress 16, no. 2 (December 1, 2016): 107–16. http://dx.doi.org/10.1515/pmp-2016-0009.

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Abstract The fields of soft magnetic composites and powder metallurgy technologies have a powerful potential to redesign the way of electric motor preparation, and will continue to grow for years to come. A design of the novel soft microcomposite material composed of spherical FeSi particles and Ni0.3Zn0.7Fe2O4 ferrite nanofibers is reported together with a characterization of basic mechanical and electrical properties. The needle-less electrospinning method was used for a preparation of Ni0.3Zn0.7Fe2O4 ferrite nanofibers, which has a spinel-type crystal structure as verified by XRD and TEM analysis. The dielectric coating was prepared by mixing of nanofibers with glycerol and ethanol because of safe manipulation with fumed fibers and homogeneous distribution of the coating around the FeSi particle surface. The final microcomposite samples were prepared by a combination of the traditional PM compaction technique supplemented with a conventional sintering process of the prepared green compacts. The composition and distribution of the secondary phase formed by the spinel ferrite fibers were examined by SEM. It is demonstrated that the prepared composite material has a tight arrangement without any significant porosity, which manifest itself through superior mechanical properties (high mechanical hardness, Young modulus, and transverse rupture strength) and specific electric resistivity compared to the related composite materials including resin as the organic binder.

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Delman, Keith A., Meredith C. Mason, and Michael C. Lowe. "Ford Versus Ferrari: Novel Technologies in the Setting of a Reliable Standard." Annals of Surgical Oncology 29, no. 2 (November 10, 2021): 758–59. http://dx.doi.org/10.1245/s10434-021-11047-1.

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Lin, Wei Ping, Ya Jun Fan, Zhan Ling Zhang, Jie Wu Zhu, and Yong Ning Liu. "Microstructure and Mechanical Properties of A Ultra-High Carbon Steel." Key Engineering Materials 324-325 (November 2006): 907–10. http://dx.doi.org/10.4028/www.scientific.net/kem.324-325.907.

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A ultrahigh carbon steels (UHCS) containing 1.6 wt pct carbon was studied. Through spheroidizing process by divorced-eutectoid transformation (DET), the forged microstructure was spheroidized and the microstructure was fine carbide particles distributed in ferrite matrix. Second-time heat treatment included two kinds of technologies: normalizing and quenching + tempering. Finally, the UHCS obtained ideal mechanical properties. The yield strength and tensile strength of the UHCS were higher than that of 40CrNiMo, moreover plasticity of the UHCS was equal to that of 40CrNiMo. So the UHCS was an excellent structural material.

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Yaya, D., D. Allassem, M. Youssouf, A. Siblini, J. P. Chatelon, and J. J. Rousseau. "Design, Manufacturing and characterization of integrated inductors with magnetic layers for DC-DC converter." Advanced Electromagnetics 1, no. 2 (October 8, 2012): 58. http://dx.doi.org/10.7716/aem.v1i2.47.

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This paper presents the conception, fabrication and characterization of integrated inductors containing magnetic layers. We require different steps of micro-technologies: preparation of glass and ferrite substrates, RF sputtering, photolithography, etching and finally electroplating techniques for copper and gold films. The geometrical magnitudes are determined by using HFSS simulator software. The measurements performed at low and high frequencies (up to 1 GHz) permit to verify the correlation between experiment and simulation results. The inductance of the manufactured spiral inductor is about 200 nH and it is constant from low frequency up to 0.9 GHz.

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Ion, Rodica-Mariana, Lorena Iancu, Ramona Marina Grigorescu, and Madalina Elena David. "Adsorption Processes Coupled with Photochemical Depolution of Waters Contaminated with Direct Orange-26 Azo Dye." Scientific Bulletin of Valahia University - Materials and Mechanics 18, no. 18 (April 1, 2022): 33–37. http://dx.doi.org/10.2478/bsmm-2022-0005.

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Abstract The present work aims to study the adsorption processes and the photochemical depollution of the waters contaminated with Direct Orange textile dyes - 26 released into the water. Also, the paper shows the polysulfone (PSf) membranes, used for adsorption processes of the textile dyes azo - direct-orange-26, presenting the kinetics and experimental adsorption conditions for such processes. Advanced oxidation processes (AOP) processes used in photochemical depollution technologies are studied for water contaminated with Direct Orange 26 textile dye, after a preliminary adsorption process, with ZnFe2O4 ferrite photocatalysts.

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Astafurov, Sergey, and Elena Astafurova. "Phase Composition of Austenitic Stainless Steels in Additive Manufacturing: A Review." Metals 11, no. 7 (June 30, 2021): 1052. http://dx.doi.org/10.3390/met11071052.

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Additive manufacturing (AM) is among the novel industrial technologies for fast prototyping of complex parts made from different constructional and functional materials. This review is focused on phase composition of additively manufactured chromium-nickel austenitic stainless steels. Being produced by conventional methods, they typically have single-phase austenitic structure, but phase composition of the steels could vary in AM. Comprehensive analysis of recent studies shows that, depending on AM technique, chemical composition, and AM process parameters, additively manufactured austenitic stainless steels could be characterized by both single-phase austenitic and multiphase structures (austenite, ferrite, σ-phase, and segregations of alloying elements). Presence of ferrite and other phases in AM steels strongly influences their properties, in particular, could increase strength characteristics and decrease ductility and corrosion resistance of the steels. Data in review give a state-of-art in mutual connection of AM method, chemical composition of raw material, and resultant phase composition of AM-fabricated Cr-Ni steels of 300-series. The possible directions for future investigations are discussed as well.

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Pullar, Robert C. "Hexagonal Ferrite Fibres and Nanofibres." Solid State Phenomena 241 (October 2015): 1–68. http://dx.doi.org/10.4028/www.scientific.net/ssp.241.1.

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Hexagonal ferrites, or hexaferrites, are hugely important materials commercially and technologically, with common applications as permanent magnets, magnetic recording and data storage media, components in electrical devices operating at wireless frequencies, and as GHz electromagnetic wave absorbers for EMC, RAM and stealth technologies. Hexaferrites are all ferrimagnetic materials, and their magnetic properties are intrinsically linked to their crystalline structures, all having a strong magnetocrystalline anisotropy; that is the induced magnetisation has a preferred orientation within the crystal structure. They can be divided into two main groups: those with an easy axis of magnetisation (known as uniaxial), the hard hexaferrites, and those with an easy plane (or cone) of magnetisation (known as ferroxplana or hexaplana), soft ferrites. The common hexaferrite members are:M-type ferrites, such as BaFe12O19and SrFe12O19Z-type ferrites (Ba3Me2Fe24O41)Y-type ferrites (Ba2Me2Fe12O22)W-type ferrites (BaMe2Fe16O27)X-type ferrites (Ba2Me2Fe28O46)U-type ferrites (Ba4Me2Fe36O60)where Me = a small 2+ion such as cobalt, nickel or zinc, and Ba can be fully substituted by Sr. Generally, the M ferrites are hard, the Y, Z and U ferrites are soft, and the W and X ferrites can very between these two extremes, but all have large magnetisation (M) values.There is currently increasing interest in composite materials containing hexaferrite fibres. It had been predicted that properties such as thermal and electrical conductivity, and magnetic, electrical and optical behaviour will be enhanced in material in fibrous form. This is because a continuous fine fibre can be considered as effectively one-dimensional, and it does not behave as a homogeneously distributed solid. Although the intrinsic magnetisation of the material is unaffected, the effective magnetisation of an aligned fibre sample should be greater when a field is applied parallel with fibre alignment compared to when applied perpendicularly to fibre alignment. This feature was first demonstrated by the author for aligned hexaferrite fibres in 2006. This chapter will deal with progress in the manufacture and properties of hexaferrite fibres, from the first syntheses of BaM, SrM,Co2Y,Co2Z, Co2W, Co2X and Co2U micron-scale fibres by the author 12-15 years ago, to recent developments in M ferrite hollow fibres and nanofibres, and hexaferrite-coated CNTs (carbon nanotubes).The relative properties of all reported hexaferrite fibres are compared and summarised at the end of this chapter.

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Łabanowski, Jerzy, Dariusz Fydrych, Grzegorz Rogalski, and Krzysztof Samson. "Underwater Welding of Duplex Stainless Steel." Solid State Phenomena 183 (December 2011): 101–6. http://dx.doi.org/10.4028/www.scientific.net/ssp.183.101.

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The present work was conducted to assess the weldability of duplex stainless steel at underwater conditions. Interest of underwater welding of this steel grade is connected with necessity of preparing welding repair technologies for subsea pipelines widely used in offshore oil and gas industry. The GMA local cavity welding method was used in the investigations. Welded beads were performed underwater at 0.5 m depth and in the air. Metallographic examinations of welds, ferrite content assessment in microstructure and hardness test were performed. The good weldability at underwater conditions of duplex stainless with the use of GMA local cavity method was confirmed.

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BOLSHAKOV, V. I., Т. О. DERHACH, and D. A. SUKHOMLYN. "SMOOTH AND REDUCED OIL AND GAS PIPES WITH INCREASED CORROSION RESISTANCE." Physical Metallurgy and Heat Treatment of Metals, no. 3 (September 28, 2021): 7–18. http://dx.doi.org/10.30838/j.pmhtm.2413.010721.7.777.

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Formulation of the problem. Corrosion of pipes used in the oil and gas industry leads to significant economic losses, therefore, increasing their corrosion resistance and durability is an urgent task. Purpose: generalization of results of developments of technologies of manufacturing and research of qualitative characteristics of oil and gas pipelines (smooth) and pump-compressor (threaded) pipes of the increased and high corrosion resistance and giving recommendations on their application in oil and gas industry in environments of various corrosion aggressiveness. Methodology. The microstructure of tubular steels and protective coatings was studied by light metallography and electron microscopy. Complex corrosion studies included laboratory tests of samples in model chloride and hydrogen sulfide-containing media, the resistance to sulfide corrosion cracking under stress (SCCS) and hydrogen cracking (НС) according to the methods of NACE TM 0177 and NACE TM 0284 as well as operational tests at the oil fields of Ukraine. Mechanical properties for stretching and impact bending of samples by standard methods. Results. The results of the development of production technologies and the study of the qualitative characteristics of oil and gas pipelines and tubing with increased and high corrosion resistance in aggressive oil and gas production environments are summarized. The influence of the chemical composition of steels and protective coatings, as well as pipe manufacturing technologies on their microstructure, corrosion resistance in various media, and mechanical properties is shown. Scientific novelty. For the first time, the presence of special low-energy boundaries in the ferrite of low-alloy ferrite-pearlite and high-alloy ferritic-austenitic steels was established, their number and energy level were estimated. The high operational reliability of threaded pipes with a protective coating is substantiated. Practical value. The results of the work and recommendations for the rational use of oil and gas pipes with increased corrosion resistance can be used to increase the economic efficiency of production in the oil and gas industry.

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Gu, Yu, Furen Xiao, Liumin Luo, Xiaoyu Zhou, Xiaodong Zhou, Jin Li, and Zhi Li. "Bacterial Disinfection by CuFe2O4 Nanoparticles Enhanced by NH2OH: A Mechanistic Study." Nanomaterials 10, no. 1 (December 19, 2019): 18. http://dx.doi.org/10.3390/nano10010018.

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Many disinfection technologies have emerged recently in water treatment industry, which are designed to inactivate water pathogens with extraordinary efficiency and minimum side effects and costs. Current disinfection processes, including chlorination, ozonation, UV irradiation, and so on, have their inherent drawbacks, and have been proven ineffective under certain scenarios. Bacterial inactivation by noble metals has been traditionally used, and copper is an ideal candidate as a bactericidal agent owing to its high abundance and low cost. Building on previous findings, we explored the bactericidal efficiency of Cu(I) and attempted to develop it into a novel water disinfection platform. Nanosized copper ferrite was synthesized, and it was reduced by hydroxylamine to form surface bound Cu(I) species. Our results showed that the generated Cu(I) on copper ferrite surface could inactivate E. coli at a much higher efficiency than Cu(II) species. Elevated reactive oxygen species’ content inside the cell primarily accounted for the strong bactericidal role of Cu(I), which may eventually lead to enhanced oxidative stress towards cell membrane, DNA, and functional proteins. The developed platform in this study is promising to be integrated into current water treatment industry.

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Marrocchino, Elena, Chiara Telloli, Sara Caraccio, Chiara Guarnieri, and Carmela Vaccaro. "Medieval Glassworks in the City of Ferrara (North Eastern Italy): The Case Study of Piazza Municipale." Heritage 3, no. 3 (July 17, 2020): 819–37. http://dx.doi.org/10.3390/heritage3030045.

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Compositional and structural characterization was carried out on transparent glass fragments found in a brick rubbish pit discovered in basal floor of the ducal palace of Ferrara, during the excavation of Piazza Municipale. This study aims to identify raw materials and glass-working techniques through X-Ray Fluorescence (XRF) quantitative chemical analyses and semi-quantitative Scanning Electron Microscopy (SEM) observations. The studied fragments were produced using siliceous-lime sands with natron as flux, and allowed us to better understand the production technologies in a historical period of great innovation for European glass art. The numerous findings of glass fragments discovered in brick underground cellars built for the specific purpose of household rubbish of wealthy complexes in Ferrara testify a consolidated system of separate discharge of solid waste into underground containers, which were closed and sealed once filled. The high volume of the finds indicates the absence of recycling of accumulated materials due to the well-being of the city. Compositional analysis confirmed the local production of glass shops in Ferrara during the late Middle Ages, characterized by differences with the glasses of the nearby city of Venice. Morphological analyses also defined the nature and relative abundance of the products, exploring the types and compositions of the Ferrara glass art.

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Kušnierová, Maria, Vladimír Šepelák, and Ol'ga Šestinová. "Bio-chemical methods in wasteprocessing." Polish Journal of Chemical Technology 11, no. 1 (January 1, 2009): 24–27. http://dx.doi.org/10.2478/v10026-009-0007-0.

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Bio-chemical methods in wasteprocessing The mineral biotechnologies, the domain of which is primary raw material processing, are increasingly diversifying into some metallurgical areas. The presented results of the research carried out with metallurgical wastes from aluminium production, lead waste remaking and desulphurization zinc-ferrite-based sorbents regeneration prove the possibility of the use of bio-chemical methods. The results obtained and the proposed technologies applying bio-chemical processes enable a complex processing and use of waste sludge from aluminium production and the use of wastes from matte-based copper production for the production of hematite pigments. The use of microorganisms in the desulphurization sorbent regeneration processes allows to increase sorbent's efficiency and its repeated recycling.

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Kuc, D., J. Szala, and I. Bednarczyk. "Quantitative Evaluation of the Microstructure and Mechanical Properties of Hot Rolled 23MnB4 Steel Grade for Cold Upsetting." Archives of Metallurgy and Materials 62, no. 2 (June 1, 2017): 551–56. http://dx.doi.org/10.1515/amm-2017-0081.

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AbstractThe article presents the results of tests of influence of the thermo-mechanical treatment parameters on the mechanical properties and microstructure of steel 23MnB4 for cold-upsetting. Measurements of the ferrite grains and pearlite colonies were conducted with the use of Met-Ilo program supplemented by additional procedures dedicated to structure analysis of ferritic-pearlitic steel. The process of rolling was conducted in simulation in semi-continuous finishing train arrangement with different temperature and cooling rate. Elaborated procedure of quantitative analysis of microstructure and conducted mechanical properties tests will be used during preparations of modified technologies of wire rod rolling to prepare products made of steel, the microstructure of which is characterised higher utility properties.

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32

Sim, Jaeyong, Sang-Hyeok Kim, Jin-Yong Kim, Ki Bong Lee, Sung-Chan Nam, and Chan Young Park. "Enhanced Carbon Dioxide Decomposition Using Activated SrFeO3−δ." Catalysts 10, no. 11 (November 3, 2020): 1278. http://dx.doi.org/10.3390/catal10111278.

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Today, climate change caused by global warming has become a worldwide problem with increasing greenhouse gas (GHG) emissions. Carbon capture and storage technologies have been developed to capture carbon dioxide (CO2); however, CO2 storage and utilization technologies are relatively less developed. In this light, we have reported efficient CO2 decomposition results using a nonperovskite metal oxide, SrFeCo0.5Ox, in a continuous-flow system. In this study, we report enhanced efficiency, reliability under isothermal conditions, and catalytic reproducibility through cyclic tests using SrFeO3−δ. This ferrite needs an activation process, and 3.5 vol% H2/N2 was used in this experiment. Activated oxygen-deficient SrFeO3−δ can decompose CO2 into carbon monoxide (CO) and carbon (C). Although SrFeO3−δ is a well-known material in different fields, no studies have reported its use in CO2 decomposition applications. The efficiency of CO2 decomposition using SrFeO3−δ reached ≥90%, and decomposition (≥80%) lasted for approximately 170 min. We also describe isothermal and cyclic experimental data for realizing commercial applications. We expect that these results will contribute to the mitigation of GHG emissions.

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Lokhande, Anirudha Pramod. "Review of Static and Dynamic Wireless Electric Vehicle Charging System." International Journal for Research in Applied Science and Engineering Technology 10, no. 2 (February 28, 2022): 127–37. http://dx.doi.org/10.22214/ijraset.2022.40201.

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Abstract: Electrified transportation will contribute to the reduction of greenhouse gas emissions and the stabilization of gasoline costs. To promote the adoption of electrified transportation, a diverse network of charging stations must be established in a userfriendly environment. Wireless electric vehicle charging systems (WEVCS) have the potential to be a viable alternative technology for charging electric cars (EVs) that do not need a plug. This article discusses the present state of wireless power transfer technologies for electric vehicles. Additionally, it contains wireless transformer constructions that have been studied using a range of ferrite forms. WEVCS are linked with health and safety concerns, which have been addressed in recent international standard development. Two main applications, static and dynamic WEVCS, are discussed, and current development is documented using features from research labs, universities, and industry. Additionally, future concepts-based WEVCS are evaluated and studied, including "vehicle-to-grid (V2G)" and "in-wheel" wireless charging systems (WCS), with qualitative comparisons to other current technologies Keywords: Combustion, Diesel Engine, Turmeric Oil, Vibration Analysis, Methyl Ester, and Blends

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Xu, Yang, Ren Bo Song, Yi Su Jia, Guo Fu Li, and Shuai Huang. "Failure Analysis of Tower Axle in the Wet Drawing Machine." Applied Mechanics and Materials 395-396 (September 2013): 782–86. http://dx.doi.org/10.4028/www.scientific.net/amm.395-396.782.

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The paper presents a failure analysis of tower axle in the water tank wire drawing machine. Material of the tower axle is 40Cr steel. In order to analyze the failure reasons of tower axle in the water tank wire drawing machine, we take experimental means such as morphological analysis, mechanical property testing, micro-metallography and scanning electron microscopy (SEM) of fracture observation, etc. The results show that the fracture of tower axle belongs to brittle fracture. The content of inclusions is more, and the composition is complex in the material. The heat treatment technology is improper. Improper quenched and tempered processing technologies cause more reticular and blocky ferrite in the steel. These are the main reasons for fracture of the tower axle.

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35

Sudarmanto, Sudarmanto. "PENGARUH PENAMBAHAN NIKEL TERHADAP KEKUATAN TARIK DAN KEKERASAN PADA BESI TUANG NODULAR 50." Angkasa: Jurnal Ilmiah Bidang Teknologi 8, no. 2 (August 25, 2017): 41. http://dx.doi.org/10.28989/angkasa.v8i2.117.

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Nodular cast iron is the cast iron that has nodular graphite spherical structure distributed in ferrite or pearlite matrix or in both of them. Recently, this material is used widely in industries because its low cost and better performance. The advanced metal industries nowadays have found some new technologies in order to improve the properties of materials. One of them is the addition of another elements into the base metals, such as nickel. The effects of the addition 1wt %, 2wt % and 3wt % nickel into nodular cast iron 50 on tensile and hardness properties were investigated in this study. The experimental results show that the best amount of nickel that added into nodular cast iron is 3% wt, which has the best tensile and hardness properties

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Dougherty, Deborah. "Managers Fail to Innovate and Academics Fail to Explain How." Management and Organization Review 14, no. 1 (March 2018): 229–39. http://dx.doi.org/10.1017/mor.2018.4.

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I am stunned by the failure of so many organizations to create the capability for generating streams of new products and services over time. Organizations capable of ongoing innovation can create more profits, more value, more employment, more growth, and more adaptability to transformations in technologies and markets (BCG study of investor returns). Generating streams of innovation is even more important now, especially for organizations in emerging economies, because industrial transformations and global grand challenges (Ferraro, Etzion, & Gehman, 2015) demand continuous innovations in products, programs, business processes, and strategies. For example, digitalization is transforming business models from vertical industrial silos such as consumer goods, materials, or financials to horizontal platforms that orchestrate networks, create technologies, and provide services (think Amazon, Alibaba). New markets and technologies emerge unpredictably but will produce major economic and social changes. Emerging economies more directly face grand challenge complexities of poverty, water scarcity, inequality, and climate changes. Innovations in emerging economy organizations are also very complex, since they often include innovations in sales, distribution, and business models along with rigorous product design and development processes.

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O’Connell, CP, SY Hyun, SH Gruber, and P. He. "Effects of barium-ferrite permanent magnets on great hammerhead shark Sphyrna mokarran behavior and implications for future conservation technologies." Endangered Species Research 26, no. 3 (January 22, 2015): 243–56. http://dx.doi.org/10.3354/esr00629.

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Hirano, Tatsumi, Daiko Takamatsu, Kosuke Kuwabara, Shuo Yuan Zhang, Takahisa Shobu, Ayumi Shiro, and Masugu Sato. "In Situ Stress Measurements during Welding Process." Materials Science Forum 905 (August 2017): 137–42. http://dx.doi.org/10.4028/www.scientific.net/msf.905.137.

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Welding technologies are indispensable for fabricating various industrial structures and must be highly reliable. Since tensile residual stresses at surface after welding cause crack progress, it is important to understand how stresses built up during the welding process in order to optimize final residual stresses as reduced tensile or introduced compressive stresses. Therefore, we conducted in-situ measurements of phase transformations, stresses and temperatures during tungsten inert gas (TIG) welding to understand how stresses built up. X-ray diffraction rings were detected per 0.1 sec during TIG welding by using a large-area two-dimensional detector and the accuracy of the stress analysis was estimated to be 8 MPa using the sin2ψ technique. In this paper, we described the phase transformations of ferrite low-carbon rolled steel and the changes in stresses during TIG welding.

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Ren, Gui Hua, and Zhi Song Yu. "Synthesis of Monodisperse Fe₃O₄ and MnFe₂O₄ Nanospheres by Using a Solvothermal Reduction Method." Solid State Phenomena 181-182 (November 2011): 393–96. http://dx.doi.org/10.4028/www.scientific.net/ssp.181-182.393.

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The spinel ferrites, MFe2O4(where M=Fe, Mn, Co, Ni, Zn, Mg, etc.) have attracted considerable interest during the last few decades due to their potential applications in high frequency transformers, filters, high density storage devices, and microwave applications. In the latest several years, many synthesis technologies such as sol-gel, auto-combustion, thermal decomposition methods and hydrothermal reaction have been developed to prepare spinel ferrite nanoparticles. In this paper, the spinel ferrites Fe3O4and MnFe2O4nanoparticles were synthesized by using a solvothermal reduction method. X-ray diffraction (XRD) and Raman analysis shows that all the peaks are close to the data for Fe3O4and MnFe2O4, indicating the prepared particles are single phase. The scan electronic microscopy (SEM) shows that the prepared Fe3O4and MnFe2O4are monodisperse nanospheres and with the average size of around 300nm.

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Barth, St, F. Kastner, M. Rößler, R. Wentorp, J. Töpfer, and Th Bartnitzek. "Low firing functional materials for application in power electronics." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2012, CICMT (September 1, 2012): 000664–69. http://dx.doi.org/10.4071/cicmt-2012-tha46.

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In the past significant effort has been obtained on the miniaturization of electronic devices, for example in the field of cellular phones or other portables devices. Mainspring of this process is the huge success that has been obtained with giant integration densities on chip level. In contrast passive components are actually the most important bottlenecks in the upcoming miniaturization process, first of all for applications in power electronics. Especially in the field of electric mobility and innovative lighting technologies an increasing demand arises for miniaturized transformers and converters. Miniaturization of power electronic devices concentrates however the dissipation heat in a smaller volume, leading in most cases to higher operation temperatures. LTCC (Low-Temperature-Cofiring-Ceramic) as a ceramic multilayer interconnection technology has been employed for the development of 3D-high integrated electronic modules, marked by an excellent thermal robustness. Actual integration of inductors or capacitors in LTCC-boards is restricted to SMD's, limiting further miniaturization in an important manner. Hence the monolithic integration of inductors and capacitors into ceramic multilayer circuit boards is a straightforward approach to gain higher integration levels in power electronics. We report on the preparation and processing of low sintering materials for the implementation of ferrite cores into LTCC multilayer boards. Different semi-finished products based on ferrite powders have been elaborated. Sintering behavior of these materials has been studied and material compatibility with different standard LTCC materials was tested.

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Nduwamungu, Aphrodis, Etienne Ntagwirumugara, Francis Mulolani, and Waqar Bashir. "Fault Ride through Capability Analysis (FRT) in Wind Power Plants with Doubly Fed Induction Generators for Smart Grid Technologies." Energies 13, no. 16 (August 17, 2020): 4260. http://dx.doi.org/10.3390/en13164260.

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Faults in electrical networks are among the key factors and sources of network disturbances. Control and automation strategies are among the key fault clearing techniques responsible for the safe operation of the system. Several researchers have revealed various constraints of control and automation strategies such as a slow dynamic response, the inability to switch the network on and off remotely, a high fault clearing time and loss minimization. For a system with wind energy technologies, if the power flow of a wind turbine is perturbed by a fault, the intermediate circuit voltage between the machine side converter and line side converter will rise to unacceptably high values due to the accumulation of energy in the DC link capacitor. To overcome the aforementioned issues, this paper used MATLAB simulations and experiments to analyze and validate the results. The results revealed that fault ride through capability with Supervisory Control and Data Acquisition (SCADA) viewer software, Active Servo software and wind sim packages are more adaptable to the variations of voltage sag, voltage swell and wind speed and avoid loss of synchronism and improve power quality. Furthermore, for protection purposes, a DC chopper and a crowbar should be incorporated into the management of excess energy during faults and a ferrite device included for the reduction of the electromagnetic field.

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42

Kairakbaev, A. K., E. S. Abdrakhimova, and V. Z. Abdrakhimov. "The Use of Waste from the Processing of Copper-Zinc Concentrates of the East Kazakhstan Region in the Production of Non-Fired Refractory Composites." Key Engineering Materials 887 (May 2021): 511–15. http://dx.doi.org/10.4028/www.scientific.net/kem.887.511.

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Creating waste-free technologies for the production of materials with high physical and thermal properties for the lining structures of thermal units is among the important environmental issues. Studies have shown that the waste of processing copper-zinc concentrates – ferrite-calcium slag crushed to pass through a sieve No. 0063 (the sieve residue is 1.2 % max.) can be used as a finely ground component of an iron phosphate binder. Studies have shown that under normal curing conditions at one-day age, refractory concretes based on an iron phosphate binder acquire strength sufficient for stripping, transportation, and installation of structures. At 7-day age, they acquire final strength, the value of which is determined by the aggregate properties. The iron phosphate binder refractoriness is 1,300 °C, and the working temperature of the concrete lining using expanded clay as coarse aggregate is 1,000 °C.

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43

Meng, Qingpu, Fuguang Huo, Song Teng, Zushan Ding, Tun Gu, and Chuang Cao. "An Autonomous Vibration-Sensing System for Power Transmission Lines Monitoring." Journal of Physics: Conference Series 2095, no. 1 (November 1, 2021): 012014. http://dx.doi.org/10.1088/1742-6596/2095/1/012014.

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Abstract An autonomous vibration-sensing system including of ring magnetoelectric energy scavenger, an energy management module, a plurality of wireless acceleration sensor nodes and APP mobile terminal for power transmission lines monitoring was presented. The ring-type ferrite/piezoelectric composite with strong magnetoelectric couplings and a coil wound around it is used to scavenge the electromagnetic energy around the conductor, and the energy management module successively fulfill the functions of inductive/capacitive resonance matching, rectification and voltage stabilization and storage/release of the scavenged electric energy, and then provides driving power for signal acquisition and data transmission of 4G wireless acceleration sensor nodes. Testing results show that the collected energy can fulfill the power-supplying requirements of ADXL345, and the real-time as well as historical data curves within a specified time can be acquired through 4G and narrowband internet of things technologies.

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44

Padinjarethil, Aiswarya Krishnakumar, Fiammetta Rita Bianchi, Barbara Bosio, and Anke Hagen. "Degradation of Ni-YSZ and Ni-GDC fuel cells after 1000 h operation: Analysis of different overpotential contributions according to electrochemical and microstructural characterization." E3S Web of Conferences 334 (2022): 04011. http://dx.doi.org/10.1051/e3sconf/202233404011.

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Solid Oxide Fuel Cell (SOFC) technologies are emerging as potential power generation units with limited environmental impacts. However, the main challenges towards large scale commercial applications are high costs and low lifetime compared to currently used technologies. The present study aims at understanding degradation mechanisms in SOFCs through both experimental and modelling approaches. For this purpose, two state of the art fuel cell configurations based on Ni cermet fuel electrode (either YSZ-Yttrium Stabilised Zirconia or GDC-Gadolinium Doped Ceria), YSZ electrolyte and LSCF (Lanthanum Strontium Cobalt Ferrite oxide) air electrode were chosen. The cells were tested for 1000 hours with H2 rich mixture as fuel feed and air as oxidant. Cells were characterised at several H2/H2O ratios and temperatures with air or oxygen fed to the air electrode using different techniques. These allowed the identification of kinetic parameters to be implemented in an in-house 2D Fortran based model. The model was able to successfully simulate global cell behaviour as a function of local features, and it was validated with experimental I-V curves recorded prior and post durability operation. Moreover, post-mortem microstructure characterisation was also performed to fine-tune the model towards a more accurate prediction of the degradation influence on cell performance.

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45

Flores, Ariadna, Karina Nesprias, Paula Vitale, Julia Tasca, Araceli Lavat, Nora Eyler, and Adriana Cañizo. "Heterogeneous Photocatalytic Discoloration/Degradation of Rhodamine B with H2O2 and Spinel Copper Ferrite Magnetic Nanoparticles." Australian Journal of Chemistry 67, no. 4 (2014): 609. http://dx.doi.org/10.1071/ch13435.

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The discoloration/degradation of the artificial dye Rhodamine B (RhB) was investigated using advanced oxidation technologies. Aqueous solutions of RhB containing spinel copper ferrites (CuFe2O4) as a heterogeneous catalyst were exposed to UV irradiation/hydrogen peroxide. Under these experimental conditions the discoloration/degradation of RhB is strongly promoted by copper ferrites, reaching 95 % discoloration of the dye in 10 min and 97 % degradation in 200 min. The influence of the catalyst amount, H2O2 concentration, light source, and UV light intensity were studied. Optimum concentrations of H2O2 and catalyst dosage were found for the RhB degradation reaction. The catalyst had high magnetic sensitivity under an external magnetic field, which allowed its magnetic separation from water avoiding secondary pollution processes, and its recycling. A markedly synergetic effect of spinel copper ferrite and UV light irradiation was observed for the RhB discoloration/degradation with H2O2 as a green oxidant.

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46

Shilyaev, P. V., S. V. Denisov, P. A. Stekanov, O. V. Sych, E. I. Khlusova, V. L. Kornilov, F. V. Kaptsan, et al. "Development and mastering of technologies of production at PJSC MMK a new generation steel rolled stock for m a in pipelines." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 77, no. 7 (August 1, 2021): 791–803. http://dx.doi.org/10.32339/0135-5910-2021-7-791-803.

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In view of arising needs of Russian oil and gas sectors, elaboration and implementation into series production competitive pipe products became an actual task for domestic enterprises of metallurgical industry. Generalized results of elaboration of chemical compositions and automated technologies of sheet rolled stock of new generation production from low-alloyed pipe steels of various strength classes at PJSC MMK presented. It was shown that the selected chemical compositions ensure forming finedispersed ferrite-bainite structure with bainite of granular morphology in a wide range of cooling rates. The elaborated technological modes of sheet rolled stock production from pipe steels stipulate for elimination considerable growth of austenite grain at heating before the rolling, refinement of austenite grains due to recrystallization processes, forming of extensive subgrain structure of austenite at plastic deformation, forming disperse structures during phase transformation in the process of controlled accelerated cooling; forming of extensive fragmented structure in а-phase. The level of strength, tough-plastic properties and resistance against brittle destruction (based on results of tests with a falling weight with determination of tough component share in the break of full-thickness samples) of sheet rolled stock of pipe steels with various chemical composition of PJSC MMK production was demonstrated. Results of study of tests the sheet rolled stock of high-strength steels for pipes of large diameter presented. Objects of the elaborated pipe steels implementation indicated.

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47

Jagielinski, Tomasz. "Materials for Future High Performance Magnetic Recording Heads." MRS Bulletin 15, no. 3 (March 1990): 36–44. http://dx.doi.org/10.1557/s0883769400060164.

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Recording in the 1990s will be high density, high frequency, in-contact recording on high coercivity media. Today's state-of-the-art head materials, NiFe, Sendust and amorphous alloys, will be used in some applications. However, layered structured and artificial superlattices will become the key head technologies of the future. Use of advanced preparation techniques will allow “true” materials engineering and the fabrication of devices to incredibly accurate specifications.These very high density recording systems will require optimal inter-play between all the components—media, head, and head/media interface. Future media will be very smooth, high coercivity, large moment thin films. The head/media spacing will be less than 50 nm, and recording at more than 100 MHz will be required. Single-track heads will be replaced by very narrow track-width multitrack devices in high data rate recorders. Thin film heads will provide the answer to most of the problems of large recording fields and high frequency response. These changes will define new requirements for head materials, some of which cannot be met by currently used materials. Conventional ferrite heads will not be found in high performance recording systems; thin film inductive and magnetoresistive (MR) heads (Figure 1) will be widely used. Thin films, metals and alloys, both crystalline and amorphous, layered structures and artificial superlattices will be the key head technologies in the future. New material preparation technologies, MBE (molecular beam epitaxy), MOCVD (molecular chemical vapor deposition), sputtering, and ion beam deposition are becoming increasingly available and less expensive. These methods will be used to fabricate future devices to incredibly accurate specifications.

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48

Hernández, Felix, and Alex Fragoso. "Fabrication of a Stainless-Steel Pump Impeller by Integrated 3D Sand Printing and Casting: Mechanical Characterization and Performance Study in a Chemical Plant." Applied Sciences 12, no. 7 (March 30, 2022): 3539. http://dx.doi.org/10.3390/app12073539.

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The emergence of additive manufacturing is renovating the landscape of available production technologies. In this paper, we describe the fabrication of a closed vane pump impeller (ϕ 206 mm, height 68 mm, weight 4 kg) by binder jetting 3D printing of a sand mould followed by casting using stainless steel 316 to create an identical copy of a part in service in a chemical plant in Tarragona, Spain. The original part was reverse engineered and used to create a sand mould by binder jetting 3D printing on which new impellers were fabricated by casting. Metallographic studies showed an austenitic matrix with 6.3% of ferritic phase and 40 μm × 8 μm ferrite grains without precipitated carbides. The impeller was put into operation in a centrifugal pump at a polyol/polyglycol plant belonging to Dow Chemical Ibérica SL from October 2020 to April 2021. Process variables related to the pump behaviour were compared with the same variables obtained in previous cycles with the original impeller for three different product viscosities (30, 180, and 500 cSt). At 500 cSt, the average current consumption was 9.34 A as compared with the 9.41 A measured with the original impeller. Similarly, the pump pressure remained essentially constant during process operation with both impellers (3.97 bar with the new impeller vs. 3.99 bar with the old). Other monitored parameters (product flow, tank level) were similar in both cases, validating the fabrication strategy from an operational point of view. This work further demonstrated that the implementation of additive manufacturing technologies in chemical process engineering is a useful solution to fabricate spare parts that are difficult to replicate with other technologies, providing consequent economic benefits.

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Pereira, F. M. M., and A. S. B. Sombra. "A Review on Ba_xSr_1-xFe₁₂O₁₉ Hexagonal Ferrites for use in Electronic Devices." Solid State Phenomena 202 (May 2013): 1–64. http://dx.doi.org/10.4028/www.scientific.net/ssp.202.1.

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The Ferrite term is used to refer to all magnetic oxides containing iron as major metallic component which has great to technological applications because of their ferromagnetic and insulating properties at room temperature. Among such ferrites, the hexagonal ones (hexaferrites) have long been used for permanent magnets and are of interest for microwave applications. The hexaferrite M-type has a structure built up from the S blocks interposed by the R block and are symbolically described as RSR*S*. In the last decades there has been great interest in the hexaferrites M-Type for applications as electronic components for mobile and wireless communications at microwave/GHz frequencies, electromagnetic wave absorbers for electromagnetic compatibility (EMC), radar absorting material (RAM) and stealth technologies and as composite materials. This review aimed study the structure, magnetic and dielectric properties of the hexaferrite BaxSr1-xFe12O19, which is a promising material for electronic devices and for small dielectric resonator antennas (MRA).The outline of this Review Paper is as follows:

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Le Petitcorps, Y., B. Guillaume, G. Campet, D. Rochier, E. Boullonnois, and B. Gufflet. "La recherche de matériaux modernes et l'utilisation de nouvelles technologies pour le confort des chevaux et du maréchal ferrant." Matériaux & Techniques 93, no. 3-4 (2005): 67–72. http://dx.doi.org/10.1051/mattech/200593067.

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Journal articles on the topic 'Ferrate technologies'

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