Impact of Thermal Treatment on the Surface of Na0.5Bi0.5TiO3-Based Ceramics

Thermal etching is a widely accepted surface treatment method for studying microstructure in Na0.5Bi0.5TiO3-based compositions. Surprisingly, besides the flat pattern of grains (suitable for evaluating ceramics’ microstructure), images illustrating well-expressed relief and even microstructure consisting of partly bonded cubic-shaped grains are also found among the micrographs presented in various publications. The present paper shows that this different surface character in Eu-modified Na0.5Bi0.5TiO3 can be obtained through thermal treatment across a wide range of temperatures. At higher temperatures, remarkable growth of cubic-shaped grains on the surface is observed. This growth affects the grain size distribution on the surface more than it does within the bulk of a sample. Such micrographs cannot be used to characterise the microstructure of dense ceramics. Intensive growth of TiO2 inclusions at high thermal treatment temperatures is also observed, revealing substantial evaporation of Bi and Na from the surface of a ceramic sample, but not from its core part.

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Mechanisms of thermal treatment on two dominant copepod species in O3/BAC processing of drinking water

Ecotoxicology ◽

10.1007/s10646-021-02392-8 ◽

2021 ◽

Author(s):

Wei Jiang ◽

Sheng Dong ◽

Fangfang Xu ◽

Jing Chen ◽

Chen Gong ◽

...

Keyword(s):

Drinking Water ◽

Thermal Treatment ◽

Southern China ◽

Paraffin Section ◽

Treatment Method ◽

Severe Damage ◽

Internal Organs ◽

Biological Activated Carbon ◽

Processing Plants ◽

Hatching Rates

AbstractPhyllodiaptomus tunguidus and Heliodiaptomus falxus are dominant copepods species in drinking water processing plants in southern China. With a potential penetration risk, the breeding and leakage of copepods are drawing more and more attention in recent years. The current study provided a thermal treatment method to control copepods and their eggs. Results showed that: (1) the immediate death rates of P. tunguidus and H. falxus after heated to 34–40 °C for 5 min are positively correlated to the treatment temperatures (P < 0.01), and all individuals of the both species were eliminated after heated at 40 °C for 5 min; (2) overall hatching rates of P. tunguidus eggs were negatively correlated with treatment temperatures (P < 0.01) between 39–45 °C, with zero percent hatched after treatment at 45 °C for 5 min; (3) hatching rates of H. falxus were negatively correlated with treatment temperatures (P < 0.01) between 37–41 °C, with no nauplii hatched when treated at 41 °C for 5 min; (4) paraffin section histological examination indicated that thermal treatment caused severe damage to internal organs and egg structure. Finally, based on the experimental data, the application of the thermal treatment method was discussed in ozonation combined with biological activated carbon (O3/BAC) processing of drink water treatment.

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Influence of Calcination Temperature on Crystal Growth and Optical Characteristics of Eu3+ Doped ZnO/Zn2SiO4 Composites Fabricated via Simple Thermal Treatment Method

Crystals ◽

10.3390/cryst11020115 ◽

2021 ◽

Vol 11 (2) ◽

pp. 115

Author(s):

Suhail Huzaifa Jaafar ◽

Mohd Hafiz Mohd Zaid ◽

Khamirul Amin Matori ◽

Sidek Hj. Ab Aziz ◽

Halimah Mohamed Kamari ◽

...

Keyword(s):

Thermal Treatment ◽

Band Gap ◽

Calcination Temperature ◽

Emission Intensity ◽

Emission Spectra ◽

Treatment Method ◽

Absorption Bands ◽

Vis Spectroscopy ◽

Doped Zno ◽

Zno Crystal

This research paper proposes the usage of a simple thermal treatment method to synthesis the pure and Eu3+ doped ZnO/Zn2SiO4 based composites which undergo calcination process at different temperatures. The effect of calcination temperatures on the structural, morphological, and optical properties of ZnO/Zn2SiO4 based composites have been studied. The XRD analysis shows the existence of two major phases which are ZnO and Zn2SiO4 crystals and supported by the finding in the FT-IR. The FESEM micrograph further confirms the existence of both ZnO and Zn2SiO4 crystal phases, with progress in the calcination temperature around 700–800 °C which affects the existence of the necking-like shape particle. Absorption humps discovered through UV-Vis spectroscopy revealed that at the higher calcination temperature effects for higher absorption intensity while absorption bands can be seen at below 400 nm with dropping of absorption bands at 370–375 nm. Two types of band gap can be seen from the energy band gap analysis which occurs from ZnO crystal and Zn2SiO4 crystal progress. It is also discovered that for Eu3+ doped ZnO/Zn2SiO4 composites, the Zn2SiO4 crystal (5.11–4.71 eV) has a higher band gap compared to the ZnO crystal (3.271–4.07 eV). While, for the photoluminescence study, excited at 400 nm, the emission spectra of Eu3+ doped ZnO/Zn2SiO4 revealed higher emission intensity compared to pure ZnO/Zn2SiO4 with higher calcination temperature exhibit higher emission intensity at 615 nm with 700 °C being the optimum temperature. The emission spectra also show that the calcination temperature contributed to enhancing the emission intensity.

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Genome-wide association study and gene network analyses reveal potential candidate genes for high night temperature tolerance in rice

Scientific Reports ◽

10.1038/s41598-021-85921-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Raju Bheemanahalli ◽

Montana Knight ◽

Cherryl Quinones ◽

Colleen J. Doherty ◽

S. V. Krishna Jagadish

Keyword(s):

Grain Size ◽

Candidate Genes ◽

Gene Network ◽

Genome Wide Association ◽

Potential Candidate ◽

Genetic Loci ◽

Stay Green ◽

Yield And Quality ◽

Genome Wide ◽

Wide Range

AbstractHigh night temperatures (HNT) are shown to significantly reduce rice (Oryza sativa L.) yield and quality. A better understanding of the genetic architecture of HNT tolerance will help rice breeders to develop varieties adapted to future warmer climates. In this study, a diverse indica rice panel displayed a wide range of phenotypic variability in yield and quality traits under control night (24 °C) and higher night (29 °C) temperatures. Genome-wide association analysis revealed 38 genetic loci associated across treatments (18 for control and 20 for HNT). Nineteen loci were detected with the relative changes in the traits between control and HNT. Positive phenotypic correlations and co-located genetic loci with previously cloned grain size genes revealed common genetic regulation between control and HNT, particularly grain size. Network-based predictive models prioritized 20 causal genes at the genetic loci based on known gene/s expression under HNT in rice. Our study provides important insights for future candidate gene validation and molecular marker development to enhance HNT tolerance in rice. Integrated physiological, genomic, and gene network-informed approaches indicate that the candidate genes for stay-green trait may be relevant to minimizing HNT-induced yield and quality losses during grain filling in rice by optimizing source-sink relationships.

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The effects and roles of PVP on the phase composition, morphology and magnetic properties of cobalt ferrite nanoparticles prepared by thermal treatment method

Fibers and Polymers ◽

10.1007/s12221-012-0831-3 ◽

2012 ◽

Vol 13 (7) ◽

pp. 831-836 ◽

Cited By ~ 10

Author(s):

Mahmoud Goodarz Naseri ◽

Elias B. Saion ◽

Saeed Setayeshi

Keyword(s):

Magnetic Properties ◽

Phase Composition ◽

Thermal Treatment ◽

Cobalt Ferrite ◽

Treatment Method ◽

Ferrite Nanoparticles ◽

Cobalt Ferrite Nanoparticles

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A Study on The Phase Transformation and Exchange-Coupling of (Nd0 95La0 05)9 5FebalCo5Nb2B10.5 Nanocomposites

MRS Proceedings ◽

10.1557/proc-577-209 ◽

1999 ◽

Vol 577 ◽

Author(s):

Q. Chen ◽

B. M. Ma ◽

B. Lu ◽

M. Q. Huang ◽

D. E. Laughlin

Keyword(s):

Grain Size ◽

Magnetic Properties ◽

Phase Transformation ◽

Thermal Treatment ◽

Grain Growth ◽

Exchange Coupling ◽

Phase Distribution ◽

Maximum Energy ◽

Treatment Temperature ◽

Phase Identification

ABSTRACTThe phase transformation and the exchange coupling in (Ndo095Lao005)9.5FebaICOsNb 2BI05 have been investigated. Nanocomposites were obtained by treating amorphous precursors at temperatures ranging from 650TC to 9500C for 10 minutes. The magnetic properties were characterized via the vibrating sample magnetometer (VSM). X-ray diffraction (XRD), thermomagnetic analysis (TMA), and transmission electron microscopy (TEM) were used to perform phase identification, measure grain size, and analyze phase distribution. The strength of the exchange coupling between the magnetically hard and soft phases in the corresponding nanocomposite was analyzed via the AM-versus-H plot. It was found that the remanence (Br), coercivity (Hci), and maximum energy product (BHmax) obtained were affected by the magnetic phases present as well as the grain size of constituent phases and their distribution. The optimal magnetic performance, BHm, occurred between 700°C to 750°C, where the crystallization has completed without excessive grain growth. TMA and TEM indicated that the system was composed of three phases at this point, Nd2(Fe Co) 14B, ca-Fe, and Fe3B. The exchange coupling interaction among these phases was consistently described via the AM-versus-H plot up to 750°C. The Br, Hci, and BHmax degraded severely when the thermal treatment temperature increased from 750°C. This degradation may be attributed to the grain growth of the main phases, from 45 to 68nm, and the development of precipitates, which grew from 5nm at 750°C to 12nm at 850°C. Moreover, the amount of the precipitates was found to increase with the thermal treatment temperatures. The precipitates, presumably borides, may cause a decrease in the amount of the a-Fe and Fe 3B and result in a redistribution of the Co in the nanocomposites. The increase of the Co content in the Nd 2(Fe Co) 14B may explain the increase of its Curie temperature with the thermal treatment temperatures. In this paper, we examine the impacts of these factors on the magnetic properties of (Ndo 95Lao 05)9 5FebaICosNb2B10.5 nanocomposite.

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The Processing of Ultrafine-Grained Materials Using High-Pressure Torsion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.558-559.1283 ◽

2007 ◽

Vol 558-559 ◽

pp. 1283-1294 ◽

Cited By ~ 1

Author(s):

Cheng Xu ◽

Z. Horita ◽

Terence G. Langdon

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

High Pressure ◽

High Pressure Torsion ◽

Metallic Materials ◽

Grain Sizes ◽

Ultrafine Grained ◽

Wide Range ◽

Ultrafine Grained Materials ◽

Thin Disks

It is now well-established that processing through the application of severe plastic deformation (SPD) leads to a significant reduction in the grain size of a wide range of metallic materials. This paper examines the fabrication of ultrafine-grained materials using high-pressure torsion (HPT) where this process is attractive because it leads to exceptional grain refinement with grain sizes that often lie in the nanometer or submicrometer ranges. Two aspects of HPT are examined. First, processing by HPT is usually confined to samples in the form of very thin disks but recent experiments demonstrate the potential for extending HPT also to bulk samples. Second, since the strains imposed in HPT vary with the distance from the center of the disk, it is important to examine the development of inhomogeneities in disk samples processed by HPT.

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Increasing Hardness of Surface Layer of Low-Carbon Steel by Account of Plasma Treatment of Coating Modification

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.316.794 ◽

2021 ◽

Vol 316 ◽

pp. 794-802

Author(s):

Andrey E. Balanovsky ◽

Van Trieu Nguyen

Keyword(s):

Surface Layer ◽

Thermal Treatment ◽

Plasma Treatment ◽

Plasma Heating ◽

High Surface ◽

Surface Hardness ◽

High Hardness ◽

Diffusion Region ◽

Low Carbon ◽

Wide Range

The Purpose of paper is to conduct studies to assess the possibility of increasing the hardness of the surface layer of steel St3 grade by plasma heating of the applied surface coating containing powder alloy PR-N80X13S2R. Mixtures of pasta were divided into 2 groups: for furnace chemical-thermal treatment and plasma surface melting. The study of the microstructure showed a difference in the depth of the saturated layer, depending on the processing method, during chemical-thermal treatment-1 mm, plasma fusion - 2 mm. The results of measuring the surface micro-hardness showed that, the obtained coating from a mixture of PR-N80X13S2R + Cr2O3 + NH4Cl has a uniform high surface hardness (31-64 HRC), from a mixture of only PR-N80X13S2R - the surface hardness varies in a wide range (15-60 HRC). The study of the microhardness of the cross section of the surface layer showed that, the diffusion region: from a mixture of powder PR-N80X13S2R + Cr2O3 + NH4Cl has uniform hardness (450-490 HV); from a mixture of PR-N80X13S2R - hardness increases in the depth of the molten region (from 300 to 600 HV), and sharply decreases in the heat affected zone (210-170 HV). The use of PR-N80X13S2R alloy powder as the main component in the composition of the paste deposited on the St3 surface during plasma treatment leads to the formation of a doped surface layer with high hardness.

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Life Cycle Comparison of Two Options for MSW Management in Puerto Rico: Thermal Treatment vs. Modern Landfilling

16th Annual North American Waste-to-Energy Conference ◽

10.1115/nawtec16-1928 ◽

2008 ◽

Cited By ~ 1

Author(s):

Giselle Balaguer-Da´tiz ◽

Nikhil Krishnan

Keyword(s):

Puerto Rico ◽

Life Cycle ◽

Thermal Treatment ◽

Waste Management ◽

Life Cycle Inventory ◽

Landfill Gas ◽

The Body ◽

Waste To Energy ◽

Msw Management ◽

Wide Range

The management of municipal solid wastes (MSW) in Puerto Rico is becoming increasingly challenging. In recent years, several of the older landfills have closed due to lack of compliance with federal landfill requirements. Puerto Rico is an island community and there is limited space for construction of new landfills. Furthermore, Puerto Rico residents generate more waste per capita than people living on the continental US. Thermal treatment, or waste to energy (WTE) technologies are therefore a promising option for MSW management. It is critical to consider environmental impacts when making decisions related to MSW management. In this paper we quantify and compare the environmental implications of thermal treatment of MSW with modern landfilling for Puerto Rico from a life cycle perspective. The Caguas municipality is currently considering developing a thermal treatment plant. We compare this to an expansion of a landfill site in the Humacao municipality, which currently receives waste from Caguas. The scope of our analysis includes a broad suite of activities associated with management of MSW. We include: (i) the transportation of MSW; (ii) the impacts of managing waste (e.g., landfill gas emissions and potential aqueous run-off with landfills; air emissions of metals, dioxins and greenhouse gases) and (iii) the implications of energy and materials offsets from the waste management process (e.g., conversion of landfill gas to electricity, electricity produced in thermal treatment, and materials recovered from thermal treatment ash). We developed life cycle inventory models for different waste management processes, incorporating information from a wide range of sources — including peer reviewed life cycle inventory databases, the body of literature on environmental impact of waste management, and site-specific factors for Puerto Rico (e.g. waste composition, rainfall patterns, electricity mix). We managed uncertainty in data and models by constructing different scenarios for both technologies based on realistic ranges of emission factors. The results show that thermal treatment of the unrecyclable part of the waste stream is the preferred option for waste management when compared to modern landfilling. Furthermore, Eco-indicator 99 method is used to investigate the human health, ecosystem quality and resource use impact categories.

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Application of Electron Backscatter Diffraction (EBSD) for Crystallographic Characterization of Aluminum-Doped Zinc Oxide Sputtered Films

Microscopy and Microanalysis ◽

10.1017/s143192761300113x ◽

2013 ◽

Vol 19 (S4) ◽

pp. 103-104

Author(s):

C.B. Garcia ◽

E. Ariza ◽

C.J. Tavares

Keyword(s):

Electron Microscopy ◽

Grain Size ◽

Zinc Oxide ◽

Electron Backscatter Diffraction ◽

Wide Range ◽

Electron Backscatter ◽

Aluminum Doped Zinc Oxide ◽

Ebsd Technique ◽

Backscatter Diffraction

Zinc Oxide is a wide band-gap compound semiconductor that has been used in optoelectronic and photovoltaic applications due to its good electrical and optical properties. Aluminium has been an efficient n-type dopant for ZnO to produce low resistivity films and high transparency to visible light. In addition, the improvement of these properties also depends on the morphology, crystalline structure and deposition parameters. In this work, ZnO:Al films were produced by d.c. pulsed magnetron sputtering deposition from a ZnO ceramic target (2.0 wt% Al2O3) on glass substrates, at a temperature of 250 ºC.The crystallographic orientation of aluminum doped zinc oxide (ZnO:Al) thin films has been studied by Electron Backscatter Diffraction (EBSD) technique. EBSD coupled with Scanning Electron Microscopy (SEM) is a powerful tool for the microstructural and crystallographic characterization of a wide range of materials.The investigation by EBSD technique of such films presents some challenges since this analysis requires a flat and smooth surface. This is a necessary condition to avoid any shadow effects during the experiments performed with high tilting conditions (70º). This is also essential to ensure a good control of the three dimensional projection of the crystalline axes on the geometrical references related to the sample.Crystalline texture is described by the inverse pole figure (IPF) maps (Figure 1). Through EBSD analysis it was observed that the external surface of the film presents a strong texture on the basal plane orientation (grains highlighted in red colour). Furthermore it was possible to verify that the grain size strongly depends on the deposition time (Figure 1 (a) and (b)). The electrical and optical film properties improve with increasing of the grain size, which can be mainly, attributed to the decrease in scattering grain boundaries which leads to an increasing in carrier mobility (Figure 2).The authors kindly acknowledge the financial support from the Portuguese Foundation for Science and Technology (FCT) scientific program for the National Network of Electron Microscopy (RNME) EDE/1511/RME/2005.

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