Study of Drying Conditions of the Aerogel Obtained by the Sol-Gel Technique for Immobilization In Situ of Lipase Candida antarctica B

In the present research, [MG49-LiClO4]:[HNO3-THF/TiO2-SiO2] and [MG49-LiClO4]:[ClHNO2-THF/TiO2-SiO2] polymer electrolytes were first prepared through simple stepwise in situ techniques: sol-gel technique and solution-cast technique. [MG49-LiClO4]:[HNO3-THF/TiO2-SiO2] and [MG49-LiClO4]:[ClHNO2-THF/TiO2-SiO2] polymer electrolytes were then characterized through different experimental techniques. [MG49-LiClO4]:[HNO3-THF/TiO2-SiO2] and [MG49-LiClO4]:[ClHNO2-THF/TiO2-SiO2] polymer electrolytes had exhibited significant structural changes upon different salt concentrations. In the present investigation, [MG49-LiClO4]:[HNO3-THF/TiO2-SiO2] and [MG49-LiClO4]:[ClHNO2-THF/TiO2-SiO2] polymer electrolytes had attained maximum ionic conductivities (σ~10-7 S/cm at ambient temperature; 10−4 S/cm at 100°C) upon 25 wt.% salt insertion. [MG49-LiClO4]:[HNO3-THF/TiO2-SiO2] and [MG49-LiClO4]:[ClHNO2-THF/TiO2-SiO2] polymer electrolytes had exhibited distinct conduction mechanisms in similar experimental configuration. [MG49-LiClO4]:[HNO3-THF/TiO2-SiO2] and [MG49-LiClO4]:[ClHNO2-THF/TiO2-SiO2] polymer electrolytes had exhibited different stability characteristics over certain operational condition.

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Study of structural, electrical, optical and magnetic properties of Hexaferrite–Polyaniline nanocomposites

International Journal of Modern Physics B ◽

10.1142/s0217979219501340 ◽

2019 ◽

Vol 33 (13) ◽

pp. 1950134 ◽

Cited By ~ 1

Author(s):

Muhammad Ajmal ◽

M. U. Islam

Keyword(s):

Saturation Magnetization ◽

In Situ Polymerization ◽

Sol Gel ◽

Electric Polarization ◽

Room Temperature Resistivity ◽

Magnetic Studies ◽

Xrd Pattern ◽

Gel Technique ◽

Pani Matrix

Y-type hexagonal ferrite (CaBaCo2Ga[Formula: see text]Fe[Formula: see text]O[Formula: see text]) was synthesized by sol–gel technique. The ferrite–polymer composites (1−x)CaBaCo2Ga[Formula: see text]Fe[Formula: see text]O[Formula: see text]+(x)polyaniline (x=0.25, 0.50, 0.75, 1) namely PF1, PF2, PF3 and polyaniline (PANI) were synthesized by in situ polymerization. The synthesized samples were characterized by XRD, SEM, electrical and dielectric measurements, optical and magnetic studies. XRD pattern reveals a broad peak of polyaniline which is an indication of amorphous nature of PANI. Room-temperature resistivity increases from 2.14 × 101 [Formula: see text]cm to 2.78 × 10[Formula: see text]cm as ferrite content increases due to resistive behavior of the ferrite particles dispersed in the PANI matrix. The value of dielectric constant decreases at fixed frequency with increasing concentration of ferrite filler which is predominantly due to exchange of electrons between Fe[Formula: see text] and Fe[Formula: see text] ions that ultimately results in enhancement of electric polarization and conductivity. The optical bandgap increases with increasing amount of ferrite in the composites. The saturation magnetization and remanence increase with the increase of ferrite filler amount in PANI matrix whereas coercivity decreases. The decrease in coercivity and increase in saturation magnetization are related to Brown’s relation. The present nanocomposite samples may be the best candidates for electromagnetic shielding.

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Polyamide-6,6/in situ silica hybrid nanocomposites by sol–gel technique: synthesis, characterization and properties

Polymer ◽

10.1016/j.polymer.2005.02.104 ◽

2005 ◽

Vol 46 (10) ◽

pp. 3343-3354 ◽

Cited By ~ 102

Author(s):

Rajatendu Sengupta ◽

Abhijit Bandyopadhyay ◽

Sunil Sabharwal ◽

Tapan K. Chaki ◽

Anil K. Bhowmick

Keyword(s):

Sol Gel ◽

Hybrid Nanocomposites ◽

In Situ Silica ◽

Gel Technique ◽

Silica Hybrid

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Preparation and Properties of PVC-Silica Composites using Different Catalysts Via Sol-Gel Process

MRS Proceedings ◽

10.1557/proc-576-351 ◽

1999 ◽

Vol 576 ◽

Cited By ~ 5

Author(s):

Khan M. Asif ◽

M.I. Sarwar ◽

Z. Ahmad

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Sol Gel ◽

Silica Network ◽

Transparent Films ◽

Sol Gel Process ◽

Gel Technique ◽

In Situ Generation ◽

Scanning Electron

Novel micro-composites from Polyvinyl chloride (PVC) and silica were prepared using sol-gel technique. Different catalysts were used for the in-situ generation of silica network from tetraethylorthosilicate (TEOS) in the PVC matrix. Thin transparent films containing various proportions of silica in PVC were cast by the solvent elution technique. Mechanical properties of these films were studied. The results showed an increase in the value of Young's modulus and strain at rupture by the addition of small amount of silica in PVC. However, the stress at yields point and stress at rupture decreased with the addition of silica contents. Scanning electron microscopy (SEM-EDAX) studies were also performed on these samples.

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Immobilization of Candida antarctica B (CALB) in Silica Aerogel: Morphological Characteristics and Stability

Biointerface Research in Applied Chemistry ◽

10.33263/briac106.67446756 ◽

2020 ◽

Vol 10 (6) ◽

pp. 6744-6756 ◽

Cited By ~ 1

Keyword(s):

Sol Gel ◽

Morphological Characteristics ◽

Amorphous Structure ◽

Industrial Applications ◽

Candida Antarctica ◽

Type Iv ◽

Wide Range ◽

The Stability ◽

Immobilized Calb ◽

Candida Antarctica B

Enzymes have been extensively used due to their catalytic properties, and immobilization is a promising technique to enhance their catalytic activity and stability. Lipases are enzymes naturally efficient, can be employed for the production of many different molecules, and have a wide range of industrial applications thanks to their broad selectivity. The objective of the present study was to characterize the Candida antarctica B CALB immobilized obtained using the aerogel technique regarding the morphological characteristics of the aerogel silica and its stability. For this purpose, analyzes of XRD, adsorption-desorption isotherms, TGA, SEM, and stability (storage, operational, and thermal) were performed. The supports obtained have an amorphous structure and isotherm type IV. Regarding TGA, two distinct regions were obtained and studied. Aerogels showed an increase in thermal, storage, and operational stability in relation to the free enzyme and demonstrated between 8 and 12 cycles of reuse. The contribution of this work was to present the stability advantages of the immobilized CALB enzyme through the sol-gel technique.

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Tough hybrid hydrogels based on simultaneous dual in situ sol–gel technique and radical polymerization

Journal of Applied Polymer Science ◽

10.1002/app.47742 ◽

2019 ◽

Vol 136 (27) ◽

pp. 47742

Author(s):

Juan Du ◽

Xiaohong She ◽

Wenli Zhu ◽

Huaju Zhang ◽

Tao Deng ◽

...

Keyword(s):

Radical Polymerization ◽

Sol Gel ◽

Hybrid Hydrogels ◽

Gel Technique

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Development of a potential LPG sensor based on a PANI–Co3O4 nanocomposite that functions at room temperature

New Journal of Chemistry ◽

10.1039/c9nj03940f ◽

2019 ◽

Vol 43 (44) ◽

pp. 17340-17350 ◽

Cited By ~ 1

Author(s):

Neetu Singh ◽

Prabhat Kumar Singh ◽

Mridula Singh ◽

Debraj Gangopadhyay ◽

Saurabh Kumar Singh ◽

...

Keyword(s):

Room Temperature ◽

Sol Gel ◽

Lpg Sensor ◽

Gel Technique

Nanostructured Co3O4 was synthesized by a sol–gel technique while 30% & 40% Co3O4–PANI (polyaniline) nanocomposites were successfully prepared employing an in situ polymerization technique.

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Hybrid Adhesives Filled with Functionalized and Non Functionalized Silica Nanoparticles

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.875.9 ◽

2018 ◽

Vol 875 ◽

pp. 9-13

Author(s):

José de Jesús Figueroa-Lara ◽

Miguel Torres-Rodríguez ◽

Mirella Gutiérrez-Arzaluz

Keyword(s):

Silica Nanoparticles ◽

Sol Gel ◽

Functionalized Silica ◽

Adhesive Properties ◽

Chemical Treatments ◽

Strength Tests ◽

Gel Technique ◽

Physical And Chemical ◽

Zirconia Nanoparticles

Hybrid adhesives epoxy-silica-zirconia were prepared and applied to bond aluminum sheet specimens. Silica nanoparticles were synthesized with the sol-gel “in situ” technique utilizing two different precursors, namely tetraethyl orthosilicate (TEOS) and 3 glycidyloxypropyltrimethoxysilane (GPTMS). Zirconia nanoparticles were prepared also with sol-gel technique and added to the hybrid adhesives before curing. The adhesive properties of the prepared materials were improved after performing several physical and chemical treatments to the aluminium specimens. The best apparent shear strength tests were for the adhesive hybrid materials prepared at 100°C with TEOS.

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