Medium Effects and Determination of Primary and Secondary Standards for pH Measurements in (Glycerol + Water) Solvent Media at Normal and Subzero Temperatures, With Characterization of Appropriate Salt Bridges†

2009 ◽  
Vol 54 (2) ◽  
pp. 286-293 ◽  
Author(s):  
Luigi Falciola ◽  
Annamaria Fierro ◽  
Patrizia Romana Mussini ◽  
Torquato Mussini ◽  
Manuela Rossi ◽  
...  
2004 ◽  
Vol 76 (3) ◽  
pp. 528-535 ◽  
Author(s):  
Luigi Falciola ◽  
Patrizia R. Mussini ◽  
Torquato Mussini ◽  
Pasquale Pelle

Jurnal MIPA ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 23
Author(s):  
Engellita Maneking ◽  
Hanny Frans Sangian ◽  
Seni Herlina Juita Tongkukut

Penelitian ini bertujuan untuk membuat dan mengkarakterisasi bioplastik yang memanfaatkan biomassa singkong. Pembuatan bioplastik dilakukan dengan dua variasi campuran yaitu pati singkong sebagai bahan dasar, gliserol + air sebagai plasticizer, asam asetat (cuka) sebagai katalis dan variasi kedua dengan kombinasi yang sama dengan penambahan alkohol sebagai pembanding. Karakterisasi bioplastik meliputi pengamatan permukaan menggunakan SEM; kristalinitas menggunakan XRD; penentuan gugus fungsi menggunakan FTIR; serta menganalisis sifat termal menggunakan TGA dan DSC. Hasil karakterisasi menunjukkan bahwa bioplastik dengan kombinasi pati singkong+ gliserol + air + asam asetat (cuka) + alkohol mempunyai tingkat degradasi yang tinggi. Hal ini sesuai dengan analisis XRD dimana kombinasi ini memiliki nilai kristalinitas rendah. Hasil spektra IR menunjukkan adanya gugus C-H Alkana, C=O ester, dan C-H Alkena. Sementara hasil SEM memperlihatkan permukaan yang rata dan hasil analisis TGA/DSC yang memperlihatkan pengurangan massa sebesar 2,3234 mgThis study aims to create and characterize bioplastics that utilize cassava biomass. The making of bioplastics is carried out for two variations of mixture, namely cassava starch as the material-based, glycerol + water as plasticizer, acetic acid (vinegar) as a catalyst and the second variation with the same combination with the addition of alcohol as a comparison. Characterization of bioplastics includes surface observations using SEM; crystallinity using XRD; determination of functional groups using FTIR; and analyzing of thermal properties using TGA and DSC. The characterization results show that bioplastics with a combination of cassava starch + glycerol + water + acetic acid (vinegar) + alcohol have a high degree of degradation. This is in accordance with the XRD analysis where this combination has a low crystallinity value. IR spectra showed that the presence of C-H Alkana groups, C = O esters, and C-H alkenes. While the SEM results showed a flat surface and the results of the TGA / DSC analysis which showed a mass reduction of 2.3234 mg.This study aims to create and characterize bioplastics that utilize cassava biomass. The making of bioplastics is carried out for two variations of mixture, namely cassava starch as the material-based, glycerol + water as plasticizer, acetic acid (vinegar) as a catalyst and the second variation with the same combination with the addition of alcohol as a comparison. Characterization of bioplastics includes surface observations using SEM; crystallinity using XRD; determination of functional groups using FTIR; and analyzing of thermal properties using TGA and DSC. The characterization results show that bioplastics with a combination of cassava starch + glycerol + water + acetic acid (vinegar) + alcohol have a high degree of degradation. This is in accordance with the XRD analysis where this combination has a low crystallinity value. IR spectra showed that the presence of C-H Alkana groups, C = O esters, and C-H alkenes. While the SEM results showed a flat surface and the results of the TGA / DSC analysis which showed a mass reduction of 2.3234 mg.


2020 ◽  
Vol 11 (1) ◽  
pp. 93-99
Author(s):  
Abu Zakir Morshed ◽  
Sheikh Shakib ◽  
Tanzim Jahin

Corrosion of reinforcement is an important durability concern for the structures exposed to coastal regions. Since corrosion of reinforcement involves long periods of time, impressed current technique is usually used to accelerate the corrosion of reinforcement in laboratories. Characterization of impressed current technique was the main focus of this research,which involved determination of optimum chloride content and minimum immersion time of specimens for which the application of Faraday’s law could be efficient. To obtain optimum chloride content, the electrolytes in the corrosion cell were prepared similar to that of concrete pore solutions. Concrete prisms of 200 mm by 200 mm by 300 mm were used to determine the minimum immersion time for saturation. It was found that the optimum chloride content was 35 gm/L and the minimum immersion time for saturation was 140 hours. Accounting the results, a modified expression based on Faraday’s law was proposed to calculate weight loss due to corrosion. Journal of Engineering Science 11(1), 2020, 93-99


2008 ◽  
Vol 2 (2) ◽  
pp. 155-177 ◽  
Author(s):  
Eugene Brently Young
Keyword(s):  

Eternal return is the paradox that accounts for the interplay between difference and repetition, a dynamic at the heart of Deleuze's philosophy, and Blanchot's approach to this paradox, even and especially through what it elides, further illuminates it. Deleuze draws on Blanchot's characterisations of difference, forgetting, and the unlivable to depict the ‘sense’ produced via eternal return, which, for Blanchot, is where repetition implicates or ‘carries’ pure difference. However, for Deleuze, difference and the unlivable are also developed by the living repetition or ‘contraction’ of habit, which results in his distinctive characterization of ‘force’, ‘levity’, and sense in eternal return.


2018 ◽  
Author(s):  
D. Basak ◽  
L. H. Ponce

Abstract Two case-studies on uncommon metals whiskers, performed at the Reliability Analysis Laboratory (RAL) of Northrop Grumman Innovation Systems, are presented. The components analyzed are an Oven Controlled Crystal Oscillator (OCXO) and an Electromechanical Relay. Investigative techniques were used to determine the chemical and physical makeup of the metal whiskers and develop an understanding of the underlying effects and mechanisms that caused the conditions conducive to whisker growth.


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