scholarly journals Development and Physical Characterization of α-Glucan Nanoparticles

Molecules ◽  
2020 ◽  
Vol 25 (17) ◽  
pp. 3807
Author(s):  
Kervin O. Evans ◽  
Christopher Skory ◽  
David L. Compton ◽  
Ryan Cormier ◽  
Gregory L. Côté ◽  
...  
Keyword(s):  
High Pressure ◽  
Glass Transition ◽  
Transition Temperature ◽  
Leuconostoc Mesenteroides ◽  
Elevated Temperatures ◽  
High Pressure Homogenization ◽  
Hydrophobic Core ◽  
Fluorescence Measurements ◽  
Exposure Measurements

α-Glucans that were enzymatically synthesized from sucrose using glucansucrase cloned from Leuconostoc mesenteroides NRRL B-1118 were found to have a glass transition temperature of approximately 80 °C. Using high-pressure homogenization (~70 MPa), the α-glucans were converted into nanoparticles of ~120 nm in diameter with a surface potential of ~−3 mV. Fluorescence measurements using 1,6-diphenyl-1,3,5-hexatriene (DPH) indicate that the α-glucan nanoparticles have a hydrophobic core that remains intact from 10 to 85 °C. α-Glucan nanoparticles were found to be stable for over 220 days and able to form at three pH levels. Accelerated exposure measurements demonstrated that the α-glucan nanoparticles can endure exposure to elevated temperatures up to 60 °C for 6 h intervals.

Evaluation of TFR-Characteristics in aWide Temperature Range

2013 ◽  
Vol 2013 (CICMT) ◽  
pp. 000247-000251
Author(s):  
Uwe Partsch ◽  
Christian Lenz ◽  
Marco Wenzel ◽  
Markus Eberstein
Keyword(s):  
Thermal Expansion ◽  
Glass Transition ◽  
High Temperature ◽  
Transition Temperature ◽  
Elevated Temperatures ◽  
Electronic Packages ◽  
Electrical Characteristics ◽  
Sensor Applications ◽  
Thermal Range

Thick-Film Resistors (TFR) are applied for many years for the manufacturing of ceramic electronic packages as well as for mechanical or thermal sensors. The resistors characteristics (e.g. Rsqr, HTCR, CTCR) are guaranteed by paste suppliers for a thermal range of operation between −55 and 125°C. However, specific sensor applications require higher operation temperatures of up to 500°C. In the paper the results of the characterization of commercial TFR at elevated temperatures on alumina substrates are presented. Electrical characteristics (e.g. Rsqr, HTCR, CTCR, GF) are correlated with materials characteristics (TFR thermal expansion, glass transition temperature, microstructure). Different requirements are discussed regarding an improved high temperature applicability of TFR. Advantages and limits of the commercial TFR will be presented.

scholarly journals Design of an n-type low glass transition temperature radical polymer

2021 ◽  
Author(s):  
Teng Chi ◽  
Siddhartha Akkiraju ◽  
Zihao Liang ◽  
Ying Tan ◽  
Ho Joong Kim ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Synthesis And Characterization ◽  
Design Synthesis

We document the design, synthesis, and characterization of the first low glass transition temperature, n-type (i.e., preferentially-reduced) radical polymer.

scholarly journals Tribological Analysis of Contacts Between Glass and Tungsten Carbide Near the Glass Transition Temperature

2020 ◽  
Vol 68 (4) ◽  
Author(s):  
Petr Chizhik ◽  
Marcel Friedrichs ◽  
Dirk Dietzel ◽  
André Schirmeisen
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Tungsten Carbide ◽  
Elevated Temperatures ◽  
Surface Deformation ◽  
Soda Lime ◽  
Soda Lime Glass ◽  
Precision Glass Molding ◽  
Tribological Analysis

Abstract In recent years, the tribological contact between hard solids and glass at high temperatures has been identified as a crucial aspect in emerging technical applications like e.g., precision glass molding. To optimize such tribological systems, especially, the internal transformations of the glasses need to be considered, since these can determine which kind of energy dissipation channels become relevant, when the temperature of a glass is increasing and approaching the glass transition temperature. Here, we now introduce a new tribometer specifically developed for the analysis of glasses at elevated temperatures. Using this tribometer, we characterize friction of contacts between tungsten carbide (WC) and soda lime glass as a function of temperature, while additionally PMMA was analyzed for comparison. Our experiments reveal different tribological regimes where either simple sliding, surface fracturing, or surface deformation can be identified as relevant interface processes for the tribological behavior. Graphical Abstract

Research and Characterization of CaO-SiO2-B2O3-Al2O3-La2O3 Sealant with Different Alumina for ITSOFC

2013 ◽  
Vol 750-752 ◽  
pp. 562-565
Author(s):  
Biao Qian ◽  
Jian Jun Yang ◽  
Jie Yu ◽  
Wen Hui Ma ◽  
Bo Yu ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Anode Materials ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Crystal Temperature ◽  
Alumina Tube ◽  
Melting Method ◽  
Temperature Melting

The CaO-SiO2-B2O3-Al2O3-La2O3 sealants with different alumina contents were fabricated by high-temperature melting method for intermediate temperature solid oxide fuel cell (ITSOFC). The glass transition temperature (Tg) and crystal temperature (Ts) of the sealant with different alumina content was characterized by TG-DSC. And the composition phase of the sealant was detected by XRD. The resistivity of sealant tested by electrochemical workstation was higher than 22 kΩ·cm2, which met the requirement for ITSOFC. Through the detecting of the wetting angle, the adhesion of sealant and anode materials was very good, and the single cell sealed with alumina tube successfully.

scholarly journals Polarization and Piezoelectric Properties of a Nitrile Substituted Polyimide

1996 ◽  
Vol 459 ◽  
Author(s):  
Joycelyn Simpson ◽  
Zoubeida Ounaies ◽  
Catharine Fay
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Remanent Polarization ◽  
Piezoelectric Properties ◽  
Synthesis And Characterization

ABSTRACTThis research focuses on the synthesis and characterization of a piezoelectric (β-CN)-APB/ODPA polyimide. The remanent polarization and piezoelectric d31 and g33 coefficients are reported to assess the effect of synthesis variations. Each of the materials exhibits a level of piezoelectricity which increases with temperature. The remanent polarization is retained at temperatures close to the glass transition temperature of the polyimide.

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