The Induced Changes in the Bulk Etch Rate and the Thermal Stability of PADC by the Effect of Long Storing Time at Room Temperature and Heat Treatment

In this work, the thermal stability of the room temperature ionic liquid (RTIL) 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO4]) is investigated using infrared (IR) spectroscopy. Quantitative IR absorption spectral data are measured for heated [EMIM][EtSO4]. Spectra have been collected between 25 ℃ and 100 ℃ using a heated optical cell. Multiple samples and cell pathlengths are used to determine quantitative values for the molar absorptivity of [EMIM][EtSO4]. These results are compared to previous computational models of the ion pair. These quantitative spectra are used to measure the rate of thermal decomposition of [EMIM][EtSO4] at elevated temperatures. The spectroscopic measurements of the rate of decomposition show that thermogravimetric methods overestimate the thermal stability of [EMIM][EtSO4].

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Enhanced Thermal Stability of Esterified Lignin in Different Solvent Mediums

Polymers from Renewable Resources ◽

10.1177/204124791800900103 ◽

2018 ◽

Vol 9 (1) ◽

pp. 39-49 ◽

Cited By ~ 1

Author(s):

Sharifah Nurul Ain Syed Hashim ◽

Sarani Zakaria ◽

Chin Hua Chia ◽

Sharifah Nabihah Syed Jaafar

Keyword(s):

Thermal Stability ◽

Alkaline Solution ◽

Room Temperature ◽

Hydroxyl Groups ◽

Aqueous Alkaline Solution ◽

Alkali Lignin ◽

Weight Percentage ◽

H Nmr ◽

Ft Ir ◽

Thermal Stability Of

In this study, soda alkali lignin from oil palm empty fruit bunch (EFB-AL) and kenaf core (KC-AL) are esterified with maleic anhydride under two different conditions, namely i) pyridine at temperature of 120°C for 3h and ii) aqueous alkaline solution at room temperature for 4h. As a result, the weight percentage gain (WPG) of the esterified EFB-AL (EFB-EL) and esterified KC-AL (KC-EL) in pyridine demonstrated a higher compared to aqueous alkaline solution. The FT-IR results of EFB-EL and KC-EL in both solvents exhibited some changes at the carbonyl and hydroxyl groups. Furthermore, the esterification process induced the carboxylic peak to appear in both alkali lignin samples. The outcome is confirmed by conducting H-NMR analysis, which demonstrated ester and carboxylic acid peaks within the spectral analysis. Finally, the TGA results showed both EFB-EL and KC-EL that are exposed to aqueous alkaline actually possessed better thermal stability and higher activation energy (Ea) compared to the esterified samples in pyridine.

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Thermal Stability of Magnetic Properties in Dehydrogenated Triarylmethane Resins

MRS Proceedings ◽

10.1557/proc-173-71 ◽

1989 ◽

Vol 173 ◽

Author(s):

Michiya Otani ◽

Sugio Otani

Keyword(s):

Thermal Stability ◽

Magnetic Properties ◽

Magnetic Property ◽

Room Temperature ◽

Permanent Magnets ◽

Elevated Temperatures ◽

Mechanical Response ◽

The Stability ◽

Thermal Stability Of

ABSTRACTThe stability of the magnetic properties of dehydrogenated triaryl-methane resins was investigated both at room temperature and at elevated temperatures. A magnetic property different from that reported in a previous paper was found in the course of studying the reproducibility of synthesis. This new property was examined through a mechanical response of the resins to a set of permanent magnets.

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Effect of Pre-Strain Rolling on Annealing Behavior of Friction-Stir Welded AA6061-T6 Aluminum Alloy

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.385.355 ◽

2018 ◽

Vol 385 ◽

pp. 355-358 ◽

Cited By ~ 2

Author(s):

Sergey Mironov ◽

Sergey Malopheyev ◽

Igor Vysotskiy ◽

Daria Zhemchuzhnikova ◽

Rustam Kaibyshev

Keyword(s):

Heat Treatment ◽

Thermal Stability ◽

Aluminum Alloy ◽

Cold Rolling ◽

Grain Growth ◽

Rolling Schedule ◽

Annealing Behavior ◽

Friction Stir ◽

Welding Direction ◽

Thermal Stability Of

In this work, the effect of pre-strain cold rolling on thermal stability of friction-stir welded AA6061-T6 alloy was studied. The pre-strain rolling was found to be very effective in suppression of abnormal grain growth during standard post-weld T6 heat treatment. It was also shown that the efficiency of this approach essentially depends on rolling path and the rolling along welding direction was the most effective rolling schedule.

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Synthesis of Fe-rich Fe–Al nanocrystalline solid solutions using ball milling

Journal of Materials Research ◽

10.1557/jmr.1999.0238 ◽

1999 ◽

Vol 14 (5) ◽

pp. 1760-1770 ◽

Cited By ~ 18

Author(s):

H. G. Jiang ◽

H. M. Hu ◽

E. J. Lavernia

Keyword(s):

Heat Treatment ◽

Activation Energy ◽

Thermal Stability ◽

Intermetallic Compound ◽

Ball Milling ◽

Microstructural Evolution ◽

Solid Solutions ◽

Al Alloys ◽

Time Intervals ◽

Thermal Stability Of

The synthesis of nanocrystalline Fe, Fe–4 wt% Al, and Fe–10 wt% Al solid solutions by SPEX ball milling has been studied. The microstructural evolution during ball milling, as well as subsequent heat treatment, has been characterized. The results demonstrate that ball milling promotes the formation of αFe–4 wt% Al and αFe–10 wt% Al solid solutions by reducing the activation energy of these alloys and generating thermal energy during this process. For Fe–10 wt% Al powders milled for various time intervals up to approximately 20 min, the FeAl intermetallic compound is formed. For alloys annealed at temperatures ranging from 600 to 1000 °C, the addition of 10 wt% Al to Fe significantly enhances the thermal stability of the nanocrystalline Fe–Al alloys. Interestingly, the addition of Al within the range of 4–10 wt% seems to have little effect on the thermal stability of these alloys annealed under the same conditions. Also, the thermal stability improves for alloys milled in air as opposed to those processed using Ar.

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Improvement of Thermal Stability of Nd-Tb-Fe-Co-B Sintered Magnets by Additions of Pr, Ho, Al, and Cu

Physics Research International ◽

10.1155/2012/416717 ◽

2012 ◽

Vol 2012 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

A. A. Lukin ◽

E. I. Il'yashenko ◽

A. T. Skjeltorp ◽

G. Helgesen

Keyword(s):

Heat Treatment ◽

Thermal Stability ◽

Magnetic Properties ◽

Thermal Treatment ◽

Temperature Interval ◽

Magnetic Parameters ◽

Sintered Magnets ◽

Additional Doping ◽

As Solubility ◽

Thermal Stability Of

The present work investigates the influence of Pr, Al, Cu, B and Ho which were introduced into the Co-containing sintered magnets of Nd-Dy-Tb-Fe-Co-B type on the magnetic parameters (α, Hci, Br, BHmax⁡). The effect of heat treatment parameters on magnetic properties was also studied. It was revealed that the essential alloying of NdFeB magnets by such elements as Dy, Tb, Ho, Co as well as by boron-forming elements, for example, by titanium, may lead to reducing of F-phase quantity, and, as a consequence, to decreasing of magnetic parameters. It was also shown that additional doping of such alloys by Pr, B, Al and Cu leads to a significant increase of the quantity of F-phase in magnets as well as solubility of the Dy, Tb, Ho and Co in it. This promotes the increase of magnetic parameters. It was possible to attain the following properties for the magnets (Nd0,15Pr0,35Tb0,25Ho0,25)15(Fe0,71Co0,29)bal ⋅ Al0,9Cu0,1B8,5 (at. %) after optimal thermal treatment {1175 K (3,6–7,2 ks) with slow (12–16 ks) cooling to 675 K and subsequently remaining at T=775 K for 3,6 ks—hardening}: Br=0,88 T, Hci=1760 kA/m, BHmax⁡=144 kJ/m3, α<|0,01|%/K in the temperature interval 223–323 K.

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Effects of aluminum sulfate soaking pretreatment on dimensional stability and thermostability of heat-treated wood

European Journal of Wood and Wood Products ◽

10.1007/s00107-020-01616-8 ◽

2020 ◽

Author(s):

Lijie Qu ◽

Zhenyu Wang ◽

Jing Qian ◽

Zhengbin He ◽

Songlin Yi

Keyword(s):

Heat Treatment ◽

Thermal Stability ◽

Thermal Degradation ◽

Structural Changes ◽

Aluminum Sulfate ◽

Treated Wood ◽

Treatment Temperature ◽

Chinese Fir ◽

Heat Treated ◽

Thermal Stability Of

Abstract Acidic aluminum sulfate hydrolysis solutions can be used to catalyze the thermal degradation of wood in a mild temperature environment, and thus reduce the temperature required for heat treatment process. To improve the dimensional and thermal stability of Chinese fir during heat treatment at 120 °C, 140 °C and 160 °C, this study investigated the effects of soaking pretreatment with 5%, 10% and 15% aluminum sulfate on the chemical and structural changes of the heat-treated Chinese fir. The results indicated that the samples treated at 15% aluminum sulfate concentration and 160 °C heat treatment achieved the best dimensional and thermal stability. Chemical analyses by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) indicated that the catalysis of aluminum sulfate resulted in degradation of hemicelluloses during the heat treatment, and an increase in the soaking concentration and heat treatment temperature also affected the thermal degradation of celluloses. The scanning electron microscope (SEM) and mass changes test results proved that the hydrolyzed aluminum flocs mainly adhered to the inner wall of the wood tracheid as spherical precipitates, and when the soaking concentration reached 10% and 15%, a uniform soaking effect could be achieved. The thermogravimetric (TG) analysis revealed the soaking pretreatment effectively improved the thermal stability of the heat-treated wood by physically wrapping and promoting the formation of a carbon layer on the wood surface during heat treatment. Thus, aluminum sulfate soaking pretreatment exerted a great effect on the dimensional and thermal stability of wood, allowing heat treatment to be performed at a lower temperature.

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Dependence of Vickers Hardness on Annealing Temperature at Co/Cu Multilayered Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.2399 ◽

2007 ◽

Vol 561-565 ◽

pp. 2399-2402

Author(s):

Yoshihisa Kaneko ◽

H. Sakakibara ◽

Satoshi Hashimoto

Keyword(s):

Thermal Stability ◽

Vickers Hardness ◽

Room Temperature ◽

Annealing Temperature ◽

Copper Substrate ◽

The Other ◽

Multilayered Structures ◽

Multilayered Films ◽

Hardness Tests ◽

Thermal Stability Of

Co/Cu and Ni/Cu multilayers fabricated by electroplating technique were annealed at various temperatures in order to investigate thermal stability of multilayered structures. Vickers hardness tests on the annealed Co/Cu and Ni/Cu multilayers were conducted at room temperature. It was recognized that after the annealing at 1023K the Co/Cu multilayer still maintained the hardness of as-deposited state. On the other hand, the hardness of Ni/Cu multilayer was almost identical to copper substrate after the annealing at 903K.

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LiFePO4/Li Batteries with Mixtures of Carbonate and Ionic Liquid [EMIM]+[TFSI]- as High Properties and Safety Electrolyte

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.2375 ◽

2013 ◽

Vol 275-277 ◽

pp. 2375-2380 ◽

Cited By ~ 2

Author(s):

Fei Li ◽

Shao Jun Wang ◽

Li Wei ◽

Wei Na Tao ◽

Xue Yang Dong ◽

...

Keyword(s):

Thermal Stability ◽

Room Temperature ◽

Weight Ratio ◽

Transference Number ◽

Organic Electrolyte ◽

Mixed Electrolyte ◽

Coulomb Efficiency ◽

Li Batteries ◽

Thermal Stability Of ◽

First Discharge Capacity

The electrolyte optimum composition consists of 1mol/L LiTFSI in the [EMIM]+[TFSI]-mixed with EC and DMC in weight ratio of 60:20:20. The LiFePO4/Li cell using 1 mol/L LiTFSI/([EMIM]+[TFSI]-/EC/DMC) as electrolyte show that the first coulomb efficiency was 90% and the first discharge capacity was 168mAh g-1. The 15th reversible capacities were maintain 157mAh g-1at 0.2C. Compared with traditional organic electrolyte and pure IL electrolyte, IL-based mixed electrolyte have good coulomb efficiencies and higher charge and discharge performances. The lithium transference number of IL-based mixed electrolyte at room temperature are 0.59. Thermal stability of IL-based mixed electrolyte higher than traditional organic electrolyte, and show almost non-flammability by the burning tests.

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