scholarly journals Changes in the structure and properties of ZrO2 detonation coatings during annealing

2020 ◽  
Vol 4 (4) ◽  
pp. 319-326
Author(s):  
B.K. Rakhadilov ◽  
D.N. Kakimzhanov ◽  
G. Botabaeva ◽  
D.B. Buitkenov ◽  
N. Kantai ◽  
...  
Keyword(s):  
Zirconium Dioxide ◽  
Microscopic Analysis ◽  
Thin Layers ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Detonation Spraying ◽  
Electron Microscopic ◽  
Before And After ◽  
New Generation ◽  
High Adhesive Strength

The article studied the effect of annealing on the structure and properties of zirconium dioxide coatings obtained by detonation spraying. Detonation spraying was realized on a computerized detonation spraying complex of the new generation CCDS2000. Determined that coatings made of zirconium dioxide are characterized by high adhesive strength of adherence to the substrate. Thermal annealing of coated samples was performed at temperatures of 900-1200◦ C. It was determined that the microhardness of zirconium dioxide coatings increases by 10-25% depending on the annealing temperature after annealing. The results of nanoindentation showed that the nanohardness of the coatings after annealing at 1000◦ C increases by 50%. It was determined that after annealing at 1000◦ C, the elastic modulus of the coatings increases, which indicates a decrease in plasticity and an increase in the strength of the coatings. X-ray diffraction analysis showed that the phase composition of coatings before and after annealing consists of t-ZrO2. After annealing occurs there is an increase in the degree of t-ZrO2 tetragonality. Electron microscopic analysis showed that an increase in the number and size of micro-continuity in the form of thin layers after annealing. Determined that increase the hardness of zirconium dioxide after annealing at 900-1200◦ C is associated with a higher degree of tetragonality t-ZrO2 phase.

Influence of Fly Ash Fineness on Autoclaved Energy Conservation Block's Performance and Hydration Products

2014 ◽  
Vol 599 ◽  
pp. 302-309 ◽  
Author(s):  
Bao Guo Ma ◽  
Li Xiong Cai ◽  
Shou Wei Jian ◽  
Lei Su
Keyword(s):  
Fly Ash ◽  
Microscopic Analysis ◽  
Production Performance ◽  
Strength Increase ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Specific Strength ◽  
Autoclaved Aerated Concrete ◽  
Aerated Concrete

This article discussed the influence of FA fineness on the production performance and usability through the autoclaved aerated concrete slurry gas foaming curve and basic physical properties of blocks; meanwhile, studied the influence of different fineness FA on the composition and morphology of hydration products through X-ray diffraction analysis and scanning electron microscopic analysis, The results show that in the cement-fly ash-lime system autoclaved aerated concrete, the higher fineness of FA, the more water it need, and more sensitive the slurry presents; when the FA residue decrease from 17.8% to 8% through a 0.045mm square hole sieve screen, its specific surface area enlarge from 325m2/Kg to 388m2/Kg, the autoclaved aerated concrete specific strength increase by 53.24% and 40.96% in the case of the same ratio of water and resemble extended degree, respectively. Keep on increasing FA fineness does harm to its specific strength. The crystallinity of tobermorite, which is the main hydration products of autoclaved aerated concrete decreases with the increasing of FA fineness, however, crystallite size become larger.

Grafting Polymerization of D,L-Lactide on the Surface of Halloysite Nanotubes

2013 ◽  
Vol 275-277 ◽  
pp. 1742-1745 ◽  
Author(s):  
Jing Jing Li ◽  
Bing Hong Luo ◽  
Jin Xi Zhang ◽  
Ru Qiu Huo ◽  
Chang Ren Zhou
Keyword(s):  
Ring Opening ◽  
Halloysite Nanotubes ◽  
Ring Opening Polymerization ◽  
Gravimetric Analysis ◽  
Structure And Properties ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Potential Measurement ◽  
X Ray ◽  
Before And After

Halloysite nanotubes (HNTs) surface-grafting poly(D,L-lactide) (g-HNTs) were synthesized by bulk ring-opening polymerization of D,L-lactide using stannous octoate as catalyst and HNTs as co-initiator. Fourier transform infrared (FTIR), thermal gravimetric analysis (TGA), X-ray diffraction (XRD) and zeta potential measurement were employed to elucidate the structure and properties of HNTs before and after grafting with D,L-lactide. FTIR spectrum certified the existence of poly(D,L-lactide) chains on the surface of g-HNTs. The amount of surface-grafted poly(D,L-lactide) measured by TGA was 4.6% in weight. The grafted poly(D,L-lactide) chains on the surfaces of HNTs can relieve the clustering effect of HNTs to some extents.

scholarly journals Effect of Alkaline Degumming on Structure and Properties of Lotus Fibers at Different Growth Period

2015 ◽  
Vol 10 (1) ◽  
pp. 155892501501000 ◽  
Author(s):  
Fengyan Li ◽  
Hongjun Fu
Keyword(s):  
Environmental Scanning Electron Microscopy ◽  
Growth Period ◽  
Bond Rupture ◽  
Environmental Scanning ◽  
Structure And Properties ◽  
Breaking Force ◽  
X Ray Diffraction ◽  
Elongation At Break ◽  
X Ray ◽  
Before And After

Lotus fibers are pulled from different period of lotus root. Alkaline was used as degumming agent to remove non-cellulose impurities of lotus fibers. Environmental scanning electron microscopy (ESEM), X-ray diffraction (XRD) and FTIR were used to characterize surface morphology and microscopic structure of lotus fibers before and after degumming. The effect of alkaline degumming on tensile properties of lotus fibers is investigated. The results show that impurities remove, hydrogen bond rupture, and crystallinity of partly armorphous chain occur during alkaline degumming. All of these changes play roles in influencing fiber tensile breaking force and elongation at break.

High Temperature MOVPE Growth of AlxGa1−xN (0.2-1) Layers on Sapphire and SiC Substrates for the Fabrication Deep UV Optical Devices

2006 ◽  
Vol 955 ◽  
Author(s):  
Balakrishnan Krishnan ◽  
Masataka Imura ◽  
Kazuyoshi Iida ◽  
Kentaro Nagamatsu ◽  
Hiroki Sugimura ◽  
...  
Keyword(s):  
High Temperature ◽  
Microscopic Analysis ◽  
Dislocation Loops ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Transmission Electron ◽  
Dislocation Densities ◽  
Transmission Electron Microscopic ◽  
Transmission Electron Microscopic Analysis

ABSTRACTSingle crystalline AlN epitaxial layers have been grown on and (0001) sapphire and 6H-SiC substrates by MOVPE technique at high temperatures in the range of 1340-1500°C. The structural qualities of the high temperature grown AlN layers were found to be good as evidenced by X-ray diffraction analyses results. By transmission electron microscopic analysis, dislocation densities of the layers were found to be 6.2 × 107 cm−2 or lower and the formation of dislocation loops was confirmed. High temperature bridge layers of AlN and AlxGa1−xN layers were grown on linear-groove patterned sapphire based AlN templates and 6H-SiC substrates. AlxGa1−xN bridge layers exhibited different growth behaviours depending on the direction of groove patterns on the sub-strates.

scholarly journals Transition Hausmannite Nanoparticles Embedded on Uniform Carbon Micro Spheres Synthesis for Electrochemical Examination

2019 ◽  
Vol 9 (2S2) ◽  
pp. 256-259
Keyword(s):  
Structural Parameters ◽  
Microscopic Analysis ◽  
Spectroscopic Technique ◽  
Maghemite Nanoparticles ◽  
Carbon Spheres ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Distribution Of Elements ◽  
Scanning Electron Microscopic Analysis ◽  
Charge Discharge

Carbon spheres wrapped by maghemite nanoparticles were synthesized through facile hydrothermal method. The structural parameters were analyzed through powder x-ray diffraction analysis. Functional groups were analyzed by Fourier transform infrared spectroscopic analysis. The prepared carbon spheres wrapped by maghemite nanoparticles morphology were investigated using scanning electron microscopic analysis. The elemental composition and distribution of elements were examined by energy dispersive spectroscopic technique with mapping. Redox property, charge discharge mechanism was done through cyclic voltammetry and galvanostatic charge-discharge studies.

scholarly journals Development of Alginate-Montmorillonite-Starch with Encapsulated Trichoderma harzianum and Evaluation of Conidia Shelf Life

2021 ◽  
Vol 26 (01) ◽  
pp. 87-96
Author(s):  
Fariz Adzmi
Keyword(s):  
Shelf Life ◽  
Trichoderma Harzianum ◽  
Microscopic Analysis ◽  
Threshold Value ◽  
Field Application ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic Analysis ◽  
Encapsulation Method ◽  
The Fourier Transform

Biological control agents, such as Trichoderma harzianum, are widely used in sustainable agriculture. However, commercialisation and mass production of biocontrol products have remained a challenge, especially in viability and efficiency in field application. The encapsulation method has emerged as a sophisticated technique to develop the formulation of T. harzianum. Hence, encapsulation through extrusion was used to prepare T. harzianum beads. The physical characteristics comprising weight, diameter, and swelling ability of the beads were significantly improved when the starch percentage was increased. Alginate-montmorillonite-starch (10%) revealed the lowest shrinkage and the highest swelling ability. The interaction within the functional groups of alginate, montmorillonite, and starch was confirmed by the Fourier-transform infrared spectroscopic (FTIR) study. Furthermore, scanning electron microscopic analysis exposed compatible scattering of montmorillonite particles and starch granules over the alginate linkages. Meanwhile, the X-ray diffraction analysis confirmed the exfoliation between starch and montmorillonite. Storage of T. harzianum beads at 5°C was more suitable than storage at 28°C. At low temperature, the encapsulated T. harzianum beads maintained their viability at 6.59 ± 0.12 log CFU g−1 for an effective threshold value for up to seven months. The current findings indicated that the combination of alginate, montmorillonite, and starch is the best formulation of encapsulated T. harzianum with improved conidia shelf life. © 2021 Friends Science Publishers

scholarly journals Effective Temperature of ZnO Nanoparticles

2020 ◽  
pp. 213-218
Author(s):  
San San Htwe ◽  
Sanda Win ◽  
Myint Myint Swe ◽  
Sandar Win
Keyword(s):  
Modern Science ◽  
Microscopic Analysis ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Zno Nps ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic ◽  
Different Temperatures ◽  
Scanning Electron Microscopic Analysis ◽  
Uv Visible

In modern science Nanotechnology is the field for the researchers. Nanoparticles have a size of 1-100 nm with a surrounding interfacial layer. Many researchers characterize significantly concerning medical chemistry, atomic physics, and all other known fields. Zinc oxide nanoparticles were synthesized with precipitation method after annealing the precursor at different temperatures. The effects of annealing temperatures for the precursors on the particle size of ZnO NPs were investigated. The structure and composition of the precursor and prepared ZnO NPs will study using X-ray diffraction (XRD), Scanning Electron Microscopic Analysis (SEM), and the optical properties of the ZnO NPs will characterize using UV-visible spectroscopy.

scholarly journals Формирование структуры гексагонального алмаза: ab initio расчеты

2019 ◽  
Vol 61 (10) ◽  
pp. 1926
Author(s):  
Е.А. Беленков ◽  
В.А. Грешняков
Keyword(s):  
Uniaxial Compression ◽  
Density Functional ◽  
Theoretical Calculations ◽  
Density Functional Theory Method ◽  
Microscopic Analysis ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Hexagonal Diamond ◽  
Molecular Layers

Modeling of the structure formation of hexagonal diamond from graphite and cubic diamond was performed using the density functional theory method. The transformation of orthorhombic AB graphite into hexagonal diamond can occur as a result of uniaxial compression at pressures above 61 GPa. For the formation of hexagonal diamond from AA graphite, the pressure must exceed 57 GPa. Another possible way to obtain hexagonal diamond is uniaxial compression of cubic diamond at pressures from 300 to 380 GPa. The data of theoretical calculations were used to interpret the diffraction data obtained as a result of X-ray diffraction and electron microscopic analysis of natural and synthetic diamond-like materials. It was found that crystals with the ideal cubic and hexagonal structure are not contained in diamond-like carbon materials, and their structure is characterized by random packing of molecular layers.

A Hydrophobic Bombyx Silk Preparation Using Sol-Gel Techniques

2011 ◽  
Vol 175-176 ◽  
pp. 276-279
Author(s):  
Yi Hu ◽  
Jing Hong Yuan
Keyword(s):  
Sol Gel ◽  
Fiber Surface ◽  
Microscopic Analysis ◽  
Lower Surface ◽  
Water Repellent ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Water Contact ◽  
Sol Gel Process ◽  
Silk Fabrics

A hydrophobic bombyx silk achieved by sol coating is characterized. The agent was firstly prepared by Dodecafluoroheptyl-propyl-trimethoxylsilane（DFS）hydrolysis, then through a sol–gel process, it coated and gelled on the fiber surface with lower surface free energy using bombyx silk fabrics as a substrate. The results of the wide-angle X-ray diffraction measurements (WAXD), TGA and DTG indicated that the thermal stability of the modified fiber was improved with the sol introduction. Scanning electron microscopic analysis (SEM) showed the morphology of the fibers in detail. The results indicated that the treated textiles had excellent water repellent property and water contact angle (CA) increased to 120.2 o.

scholarly journals Effects of Boron and Carbon Added Titanium Filler on Microstructure and Mechanical Properties of Ti-15-3 Alloy Weldments

2019 ◽  
Vol 7 (4.14) ◽  
pp. 538
Author(s):  
Izzul Adli Bin Mohd Arif ◽  
Mahesh Kumar Talari ◽  
N Kishore Babu ◽  
Ahmad Lutfi Bin Anis ◽  
Muhammad Hussain Ismail ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Grain Refinement ◽  
Microscopic Analysis ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Gas Tungsten Arc ◽  
Beta Titanium ◽  
Scanning Electron Microscopic ◽  
Scanning Electron Microscopic Analysis

Microstructural and mechanical properties beta Titanium (β-Ti) weldments can be improved by grain refinement and formation of insoluble precipitates in the weld. This paper reports the effect of Boron (B) and Carbon (C) addition to Ti-15V-3Cr-3Sn-3Al (Ti-15-3) fillers on the microstructural and mechanical properties of Ti-15-3 gas tungsten arc weldments. X-ray diffraction and scanning electron microscopic analysis revealed the presence of β-Ti phase in the weldments prepared without the filler modification, while additional TiB and TiC phases are observed in the weldments prepared with fillers modified with B and C, respectively. B and C addition to the fillers has resulted in the grain refinement of the weldments and the grain size reduction is seen to be higher with the increasing B and C addition. The formation of TiB, TiC and growth restriction effect due to the presence of B and C in the filler resulted in the decreased grain size of the β-Ti weldments. Mechanical properties such as hardness and tensile strength improved as the amount of B and C addition increased. The improvement of mechanical properties is contributed by the grain refinement and the formation of TiB and TiC precipitates in weldments. 

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