The VO Defect in Electron Irradiated Czochralski Silicon

2014 ◽  
Vol 1004-1005 ◽  
pp. 293-296
Author(s):  
Li Li Cai ◽  
Hui Bin Wang ◽  
Cui Ju Feng ◽  
Gui Feng Chen
Keyword(s):  
Thermal Stability ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Oxygen Content ◽  
Irradiation Dose ◽  
Linear Increase ◽  
Interstitial Oxygen ◽  
Low Oxygen ◽  
High Oxygen Content ◽  
Czochralski Silicon

The Czochralski silicon (CZ-Si) samples were irradiated with 1.5 MeV electrons and annealed at 200 - 450 °C. It was investigated the effect of irradiation dose and interstitial oxygen content [Oi] on VO concentration by Fourier transform infrared spectroscopy (FTIR). The results show that VO concentration increases with irradiation dose but not linear increase. The interstitial oxygen content has no effect on VO concentration. The VO intensity increases firstly and then decreases after annealing in samples with low oxygen content. The VO disappears at 450 °C. In high oxygen content samples, VO exhibits thermal stability and disappears at 400 °C.

The Effect of Oxygen on the Thermal Stability of Si1−xGex Strained Layers Grown by Limited Reaction Processing

1991 ◽  
Vol 220 ◽  
Author(s):  
D. B. Noble ◽  
J. L. Hoyt ◽  
P. Kuo ◽  
W. D. Nix ◽  
J. F. Gibbons ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Solid Solution ◽  
Oxygen Content ◽  
Low Oxygen ◽  
Strained Layers ◽  
High Oxygen Content ◽  
Solid Solution Strengthening ◽  
Solution Strengthening ◽  
Effect Of Oxygen ◽  
Content Support

ABSTRACTSi1−xGex layers containing 2×1020 oxygen atoms/cm3 exhibit an enhancement in thermal stability when compared to similar films (comparable Ge content and thickness) with 2 orders of magnitude less oxygen. X-ray measurements of the lattice constants in the strained films indicate that the oxygen does not substantially change the amount of strain in the layers. A prediction of the effect of oxygen based on solid solution strengthening theory is shown to be consistent with experimental annealing results. In addition, experimental measurements of slower misfit dislocation velocities in the layers with high oxygen content compared to those measured in films with low oxygen content, support the idea of solid solution strengthening. It is therefore likely that oxygen impedes the kinetics of dislocation formation.

Surface Modification of Bacterial Cellulose Sheets With Various Fire Retardants

2020 ◽  
Vol 13 (2) ◽  
Author(s):  
Eser Sözen ◽  
Gökhan Gündüz ◽  
Deniz Aydemir ◽  
Ahmet Can
Keyword(s):  
Thermal Stability ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Thermogravimetric Analysis ◽  
Phosphoric Acid ◽  
Bacterial Cellulose ◽  
Weight Percent Gain ◽  
Weight Percent ◽  
Fire Retardants ◽  
Freeze Dried

Abstract This study investigated the effects of various fire retardants including Firetex®, phosphoric acid, and nanoboron nitride on the thermal and morphological properties of bacterial cellulose (BC) sheets. Hestrin and Schramm medium was inoculated with Gluconacetobacter hansenii and the medium with the bacteria was incubated for 14 days. The obtained BC sheets were freeze-dried and then the dried sheets were immersed with Firetex®, phosohoric acid, and nanoboron nitride for a day. The sheets were once again freeze-dried and weight percent gain (WPG) of the sheets was calculated by using wet and dried weights. The morphological characterization, thermal properties, and structural changes of the obtained sheets were also investigated with scanning electron microscopy (SEM), thermogravimetric analysis, and Fourier-transform infrared spectroscopy, respectively. The weight percent gain was found to increase 31% for the samples with boron nitride and 1040% for the samples with phosphoric acid after the impregnation. The thermogravimetric analysis showed that the impregnation improved the thermal stability of the BC films. The sheets with nanoboron nitride exhibited the best thermal stability, whereas the sheets with Firetex were determined to have the worst thermal stability. The Fourier-transform infrared spectroscopy showed some changes in the structural properties of the all BC sheets with fire retardants. As a result, it can be said that nanoboron nitride at low temperatures (25–250 °C) and Firetex and phosphoric acid at higher temperatures (600–900 °C) showed better thermal stability.

Production and characterization of boron nitride-doped nanofiber mats created through electrospinning

2016 ◽  
Vol 47 (6) ◽  
pp. 993-1005 ◽  
Author(s):  
Yasemin Cakmak ◽  
M Fatih Canbolat ◽  
Enes Cakmak ◽  
Mehmet Dayik
Keyword(s):  
Thermal Stability ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Thermogravimetric Analysis ◽  
Boron Nitride ◽  
Fourier Transform Infrared Spectroscopy ◽  
Fourier Transform Infrared ◽  
Electrospinning Method ◽  
The Fourier Transform ◽  
Nanofiber Mats

The aim of this study was to produce advanced nanofiber mats by adding boron nitride to poly (ɛ-caprolactone) polymer using an electrospinning method and to characterize the resultant structures. Pure poly (ɛ-caprolactone) nanofiber mats and boron nitride-doped nanofiber mats prepared at different concentrations were compared. The morphological structures of the nanofiber mats were examined under a scanning electron microscope, spectroscopic analyses were conducted using Fourier transform infrared spectroscopy, and thermal stability was analyzed using a thermogravimetric analysis method. Successful electrospinning of boron nitride-doped nanofibers at lower voltages was achieved. The thermogravimetric analysis test found that the thermal stability of boron nitride-doped nanofiber mats is higher than that of pure nanofibers, which suggests that the produced composite material could be preferable in applications involving insulation and high temperature. On the other hand, the Fourier transform infrared spectroscopy results indicated that no chemical reaction occurred between boron nitride and the poly (ɛ-caprolactone) nanofibers.

scholarly journals Morphological and thermal properties of composites prepared with poly(lactic acid), poly(ethylene-alt-maleic anhydride), and biochar from microwave-pyrolyzed jatropha seeds

BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 3171-3185
Author(s):  
Perry Law Nyuk Khui ◽  
Rezaur Rahman ◽  
Abu Saleh Ahmed ◽  
Kuok King Kuok ◽  
Muhammad Khusairy Bin Bakri ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Fourier Transform ◽  
Thermal Properties ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Filler Content ◽  
Scanning Calorimetry ◽  
Jatropha Seeds ◽  
Properties Of Composites

The morphological and thermal properties of composites containing a bioplastic blend and micro/nano-sized biochar from pyrolyzed jatropha seeds from microwave pyrolyzed jatropha seeds were investigated using scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The biocomposite samples exhibited a brittle structure with a slightly ductile chip-like appearance. The Fourier transform infrared spectroscopy results for the PLA/PEMA/BC bio-composites were comparable to the PLA/BC biocomposites. A lower bio-filler content had more pronounced peak intensities than the higher bio-filler content biocomposites. The added PEMA compatibilizer in the PLA/PEMA/BC biocomposite showed more pronounced peaks, which indicated slightly improved bonding/interaction between the bio-filler and the matrix. Overall, increasing bio-filler content did not drastically affect the functional groups of the biocomposites. Thermogravimetric and differential scanning calorimetry analysis showed the developed biocomposites had a slight improvement in thermal stability, in comparison to the PLA sample. Improvements in the thermal stability of the PLA/PEMA/BC biocomposite could be attributed to the additional hydroxyl group, which was due to the added PEMA in the PLA and PLA/BC. According to the results of the analysis of the developed biocomposites, the biocomposites were more brittle and had reasonable thermal stability.

scholarly journals Experimental Study of Bentonite-Free Water Based Mud Reinforced with Carboxymethylated Tapioca Starch: Rheological Modeling and Optimization Using Response Surface Methodology (RSM)

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3320
Author(s):  
Imtiaz Ali ◽  
Maqsood Ahmad ◽  
Tarek Ganat
Keyword(s):  
Thermal Stability ◽  
Response Surface Methodology ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Yield Point ◽  
Modified Starch ◽  
X Ray Diffraction ◽  
Tapioca Starch ◽  
X Ray ◽  
Water Based

Drilling mud’s rheological characteristics, such as plastic viscosity and yield point, are adversely affected with an inappropriate mud formulation. Native starch is one of the most important components in water-based mud because it improves the rheological and filtration characteristics of the mud. The native starch stability under various temperature and exposure time regimes is an important concern for utilizing starch in oil and gas drilling operations. In this work, tapioca starch was modified using carboxymethylation for the first time in order to improve its performance in non-damaging water-based muds. The modified starch was characterized by Fourier-transform infrared spectroscopy and X-ray diffraction. The thermal stability was tested using thermal gravimetric analysis. Various mud blends were formulated based on the experimental design using response surface methodology (RSM) to investigate their performance at various temperature conditions. Thirty experimental runs were carried out based on the selected factors and responses considering the optimal (custom) design, and the results were analyzed through ANOVA. The Fourier-transform infrared spectroscopy and X-ray diffraction results confirmed the carboxymethylation of starch. The TGA analysis revealed strong thermal stability after modification. Additionally, the Power law model (PLM) described the obtained rheological data for the selected formulations, resulting in determination coefficients of more than 0.95. Furthermore, the examined samples showed a reduction in the flow behavior index from 0.30 to 0.21 and an increase in the consistency index from 5.6 to 15.1. Optimization and confirmation results revealed the adequacy of the generated empirical models for both plastic viscosity and yield point. The obtained consistency index values provided a direct relationship with the modified starch concentration, indicating an improvement in the cutting carrying capacity of mud. Based on the current literature survey, the studied formulation has not been reported in the literature.

Synthesis, Characterization and Flame Retardancy of Two Novels Amino Phosphate

2012 ◽  
Vol 554-556 ◽  
pp. 110-114
Author(s):  
Da Ming Ban ◽  
Yang Min ◽  
Yong Hang Zhang ◽  
Ou Zhao
Keyword(s):  
Thermal Stability ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Flame Retardant ◽  
Elemental Analysis ◽  
Flame Retardancy ◽  
Spectroscopic Data ◽  
Polyamide 6 ◽  
Phosphorus Containing ◽  
Thermal Stability Of

Two phosphorus-containing flame retardant (FR) were synthesized and incorporated in the backbone of polyamide 6(PA6) by polymerization. The structure and spectroscopic data of these flame retardant were determined by Fourier Transform Infrared Spectroscopy (FTIR) and Elemental analysis. Flame-retardancy and thermal property of PA6 modified with CEP, and MMP were examined by LOI and TGA. The LOI value of PA6 shows ascending trend by adding FRs, and it rise from 24 to 31%. TGA data revealed that FR improves thermal stability of PA6. The on-set temperature was added at least 20°C.

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