Synthesis and Characterization of Multi-Angular Branched ZnO Microstructures and Peculiar Nanopushpins Obtained by Thermal Treatment from Compacted ZnS Powder

2019 ◽  
Vol 286 ◽  
pp. 23-30
Author(s):  
J.R. Mora ◽  
Gregorio Flores-Carrasco ◽  
Mauricio Pacio ◽  
T.G. Díaz-Rodríguez ◽  
Hector Juárez
Keyword(s):  
Thermal Treatment ◽  
Treatment Process ◽  
Treatment Temperature ◽  
Complex Structures ◽  
Wurtzite Phase ◽  
Free Process ◽  
Different Temperatures ◽  
Short Time ◽  
Hexagonal Wurtzite Phase

Multi-angular branched ZnO microstructures with rods-shaped tips and nanopushpins with hexagonal cap on top have been synthesized by a simple thermal treatment process of compacted ZnS powder used as starting material and substrate. The structures have been grown at different temperatures (800, 900 and 1000 °C) for 60 min, in a constant nitrogen environment at atmospheric pressure via a catalyst-free process. XRD results of the as-grown products from ZnS powder show a significant reduction in the cubic zincblende phase to the hexagonal wurtzite phase with the increase of treatment temperature, as compared to the bulk value. Post-anneal analyses indicated that the transformation of morphologies of the as-grown structures also depends strongly on the treatment temperature. The proposed method represents an easy and economical way to grow complex structures of ZnO, with a relatively short time, furthermore, without the neediness of use an external substrate to grow. These new and interesting nanostructures have potential in applications such as optoelectronics.

Effect of manufacturing parameters and thermal treatment on the properties of tubular braids and tubular knits

2016 ◽  
Vol 36 (4) ◽  
pp. 421-430
Author(s):  
Ching-Wen Lou ◽  
Po-Ching Lu ◽  
Jin-Jia Hu ◽  
Jia-Horng Lin
Keyword(s):  
Thermal Treatment ◽  
Three Dimensional ◽  
Textile Composites ◽  
Treatment Temperature ◽  
Test Results ◽  
Thermal Treatment Temperature ◽  
Medical Textiles ◽  
Different Temperatures ◽  
Conductive Textile ◽  
Manufacturing Parameters

Abstract Textile techniques can be applied to create two-dimensional or three-dimensional tubular fabrics. Three-dimensional tubular knits can be used in many fields, such as for medical textiles, conductive textile, composites, and tissue engineering. This study aimed to examine the effects of different yarn types on various fabrics and of different temperatures on the variations in the properties of textiles. Four types of wrapped yarn (P150, P75, S140, and S70) were made into tubular braids and knits, after which the products were thermally treated at various temperatures (120°C, 140°C, and 160°C). A shrinkage measurement, a porosity test, a braid angle test, and a tensile test were performed to evaluate the tubular braids and knits. The test results indicated that the thermal treatment temperature did not affect the porosity of the tubular braids and tubular knits. The porosity of the tubular braids was between 40.32% and 48.27%, while that of the tubular knits was between 10.15% and 35.57%. In addition, the tensile strength of both fabric types increased by 40–50%, while their displacement increased by 200–250%. In the future, the efficacy of tubular braids and tubular knits for use as vascular grafts will be examined.

scholarly journals The Effect of Short Time Thermal Treatment on Swelling of Field Maple (Acer campestre L.) and Fir (Abies alba Mill.)

2020 ◽  
Vol 68 (3) ◽  
pp. 483-490
Author(s):  
Holta Çota ◽  
Leonidha Peri ◽  
Entela Lato ◽  
Hektor Thoma ◽  
Doklea Quku ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Thermal Treatment ◽  
Mass Loss ◽  
Abies Alba ◽  
Untreated Wood ◽  
Wood Industry ◽  
Time Duration ◽  
Acer Campestre ◽  
Different Temperatures ◽  
Short Time

From the immemorial time wood is highly abundant and well-performing material. Further one due to practical use the wood heat treatment, as a process for improving its properties has been enhanced in the recent tim. Abies alba Mill and Acer campestre L. are among the most wide spread species in Albanian forest and among the most useful types of wood in Albanian wood industry. The objective of this study is to investigate the influence of short time heat treatment on dimensional stability and the mass loss of these two species. Wood samples are treated in three different temperatures (180 ℃, 200 ℃, 220 ℃) and two different time durations of 15 and 30 minutes. After the heat treatment, the mass loss is determined for treated samples. Treated and untreated samples are immersed in water and the swelling is determined. According to the results obtained, wood swelling undergoes a considerable reduction in the case of wood treatment at a temperature of 220 ℃ for the longest time duration of 30 minutes. The higher percentage of weight loss after the thermal treatment (9.66% for the maple and 10.77% for the fir) was measured in the samples treated in a 220 ℃ for 30 minutes. The results of both treated and untreated wood were given for comparative purposes.

scholarly journals INFLUENCE OF COMMERCIAL THERMAL TREATMENT ON Eucalyptus grandis Hill ex Maiden WOOD PROPERTIES

2021 ◽  
Vol 45 ◽  
Author(s):  
Carolina Aparecida Barros Oliveira ◽  
Karina Aparecida de Oliveira ◽  
Julio Cesar Molina ◽  
Vinicius Borges de Moura Aquino ◽  
André Luis Christoforo
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Thermal Treatment ◽  
Eucalyptus Grandis ◽  
Treated Wood ◽  
Wood Properties ◽  
Treatment Temperature ◽  
Saturated Steam ◽  
Physical Chemical ◽  
Different Temperatures

ABSTRACT This study aimed to evaluate the influence of commercial thermal treatment on Eucalyptus grandis considering its physical, chemical, and mechanical properties. The wood samples were heat-treated in an autoclave with saturated steam and pressure application at four different temperatures: 155, 165, 175, and 185 ºC. The physical, chemical, and mechanical properties were altered due to the heat treatment. The extractives content varied between 6.06% and 28.75%; lignin between 28.93% and 37.96%; holocellulose between 65.01% and 38.12%. The mechanical properties reduced significantly with the increase of the heat treatment temperature. Through the set of data obtained, it was possible to generate significant and high precision regression models capable of estimating such properties for heat treatment temperatures not studied experimentally, enabling the determination of the most suitable temperature of heat treatment to achieve a certain property value of the treated wood.

Synthesis and Characterization of Co3O4 Nanoparticles by Thermal Treatment Process

2012 ◽  
Vol 23 (2) ◽  
pp. 557-565 ◽  
Author(s):  
Afsaneh Khansari ◽  
Masoud Salavati-Niasari ◽  
Ali Kazemi Babaheydari
Keyword(s):  
Thermal Treatment ◽  
Treatment Process ◽  
Synthesis And Characterization ◽  
Co3o4 Nanoparticles

Characterization of Sludge after Thermal Treatment

2006 ◽  
Vol 530-531 ◽  
pp. 715-719
Author(s):  
L.C. Morais ◽  
Jo Dweck ◽  
E.M. Gonçalves ◽  
Pedro M. Büchler
Keyword(s):  
Electron Microscopy ◽  
Thermal Treatment ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Different Temperatures ◽  
Physical And Chemical ◽  
Scanning Electron ◽  
And Chemical Properties

The aim of this paper was to study the characterization of sludge affected by different thermal treatment, on selected physical and chemical properties. Sludge incinerated ash has been fired at different temperatures. This material was fired at 1050 °C for 3 h and until a peak of 1010°C. After thermal treatment the ash were screened at 200 mesh. The ash was characterized by X-ray fluorescence and trace elements like Cr, Pb, Zn, Cu, and some oxides like quartz(SiO2), Al2O3, P2O5, Fe2O3 were found. Scanning electron microscopy (SEM) has shown one change of particle between 2μm at 90μm and apparent porosity.

EXELFS Studies of Carbon Fibers

1990 ◽  
Vol 48 (2) ◽  
pp. 72-73
Author(s):  
V. Serin ◽  
K. Hssein ◽  
G. Zanchi ◽  
J. Sévely
Keyword(s):  
Carbon Fibers ◽  
Energy Analysis ◽  
Electron Excitation ◽  
Complex Structures ◽  
High Modulus ◽  
Promising Technique ◽  
X Ray ◽  
Fine Structures ◽  
X Ray Absorption

The present developments of electron energy analysis in the microscopes by E.E.L.S. allow an accurate recording of the spectra and of their different complex structures associated with the inner shell electron excitation by the incident electrons (1). Among these structures, the Extended Energy Loss Fine Structures (EXELFS) are of particular interest. They are equivalent to the well known EXAFS oscillations in X-ray absorption spectroscopy. Due to the EELS characteristic, the Fourier analysis of EXELFS oscillations appears as a promising technique for the characterization of composite materials, the major constituents of which are low Z elements. Using EXELFS, we have developed a microstructural study of carbon fibers. This analysis concerns the carbon K edge, which appears in the spectra at 285 eV. The purpose of the paper is to compare the local short range order, determined by this way in the case of Courtauld HTS and P100 ex-polyacrylonitrile carbon fibers, which are high tensile strength (HTS) and high modulus (HM) fibers respectively.

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

2019 ◽  
Author(s):  
Priya Prakash ◽  
Travis Lantz ◽  
Krupal P. Jethava ◽  
Gaurav Chopra
Keyword(s):  
Amyloid Beta ◽  
Western Blots ◽  
Force Microscopy ◽  
E Coli ◽  
Atomic Force ◽  
Set Up ◽  
Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

Synthesis and Characterization of Nanocrystalline ZnO Powders by a Direct Thermal Decomposition Route Using Zinc Nitrate Hexahydrate

2013 ◽  
Vol 770 ◽  
pp. 68-71 ◽  
Author(s):  
Supphadate Sujinnapram ◽  
Uraiphorn Termsuk ◽  
Atcharawan Charoentam ◽  
Sutthipoj Sutthana
Keyword(s):  
Thermal Decomposition ◽  
Crystallization Temperature ◽  
Zinc Nitrate ◽  
Zinc Nitrate Hexahydrate ◽  
Absorption Peak ◽  
Synthesis And Characterization ◽  
Nitrate Hexahydrate ◽  
Different Temperatures ◽  
Zno Powders

The nanocrystalline ZnO powders were synthesized by a direct thermal decomposition using zinc nitrate hexahydrate as starting materials. The precursor was characterized by TG-DTA to determine the thermal decomposition and crystallization temperature which was found to be at 325 oC. The precursors were calcined at different temperatures of 400, 500, and 600°C for 4 h. The structure of the prepared samples was studied by XRD, confirming the formation of wurtzite structure. The synthesized powders exhibited the UV absorption below 400 nm (3.10 eV) with a well defined absorption peak at around 285 nm (4.35 eV). The estimated direct bandgaps were obtained to be 3.19, 3.16, and 3.14 eV for the ZnO samples thermally decomposed at 400, 500, and 600°C, respectively.

scholarly journals Synthesis and characterization of Cu(OH)2-NWs-PVA-AC Nano-composite and its use as an efficient adsorbent for removal of methylene blue

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sivarama Krishna Lakkaboyana ◽  
Khantong Soontarapa ◽  
Nabel Kalel Asmel ◽  
Vinay Kumar ◽  
Ravi Kumar Marella ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Kinetic Models ◽  
Batch Reactor ◽  
Maximum Adsorption Capacity ◽  
Nano Composite ◽  
Adsorption Processes ◽  
Intra Particle Diffusion ◽  
Short Time ◽  
Efficient Adsorbent

AbstractThe present study focused on the synthesis of copper hydroxide nanowires decorated on activated carbon (Cu(OH)2-NWs-PVA-AC). The obtained Cu(OH)2-NWs-PVA-AC Nano-composite was distinguished by XRD, SEM, EDX, BET, FTIR and XPS respectively. Besides, different variables such as solution pH, and initial dye concentration, contact time, and temperature were performed on the adsorption efficiency of MB in a small batch reactor. Further, the experimental results are analyzed by various kinetic models via PFO, PSO, intra-particle diffusion and Elovich models, and the results revealed that among the kinetic models, PSO shows more suitability. In addition, different adsorption isotherms were applied to the obtained experimental data and found that Langmuir–Freundlich and Langmuir isotherm were best fits with the maximum adsorption capacity of 139.9 and 107.6 mg/g, respectively. The Nano-composite has outstanding MB removal efficiency of 94–98.5% with a span of 10 min. and decent adsorption of about 98.5% at a pH of 10. Thermodynamic constants like Gibbs free energy, entropy, and enthalpy were analyzed from the temperature reliance. The results reveal the adsorption processes are spontaneous and exothermic in nature. The high negative value of ΔG° (− 44.11 to − 48.86 kJ/mol) and a low negative value of ΔH° (− 28.96 kJ/mol) show the feasibility and exothermic nature of the adsorption process. The synthesized dye was found to be an efficient adsorbent for the potential removal of cationic dye (methylene blue) from wastewater within a short time.

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