Influence of alcohol on mechanical and electrical properties of thin organic films

AbstractStability of organic materials properties is essential for further applications and was intensely investigated in last few decades. The aim of this study is to detect the structural changes of dipalmitoyl-phosphatidylcholine (DPPC) monolayer as a model system of organic material under influence of alcohols solutions. As subphases of monolayers (Langmuir films), pure water, ethanol and methanol solutions were used. For detection of changes in charge states of the molecules as well as relation with structural and conformational changes, a contactless method employing Maxwell’s displacement currents (MDC) was used. In DPPC monolayer on the subphase of methanol-water, a gradual absorption of methanol molecules into the layer can appear. In DPPC monolayer on the subphase of ethanol-water adsorption of ethanol molecules on the layer can be observed. Influence of alcohols results in a significant change of mechanical and electrical properties as well as in the stability of thin films.

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Properties of Barium Cerate Thin Films Formed Using E-Beam Deposition

Crystals ◽

10.3390/cryst10121152 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1152

Author(s):

Monica Susana Campos Covarrubias ◽

Mantas Sriubas ◽

Kristina Bockute ◽

Piotr Winiarz ◽

Tadeusz Miruszewski ◽

...

Keyword(s):

Thin Films ◽

Phase Composition ◽

Electrical Properties ◽

Total Conductivity ◽

Barium Cerate ◽

Technological Parameters ◽

Thermal Expansion Coefficients ◽

Mechanical And Electrical Properties ◽

The Stability ◽

Strained Films

This article focuses on the properties of the BaCeO3 thin films formed by electron-beam vapor deposition and investigates the formation of barium cerates on supports with different thermal expansion coefficients (Stainless Steel, Invar, Glass Sealing, and Inconel substrates) and the influence of the technological parameters on the properties of the formed thin films with an emphasis on the stability of the films. Morphology and phase composition and mechanical and electrical properties were investigated. It was found that the main factors influencing the phase composition and morphology of the films are the temperature of the support and the deposition rate. However, the mechanical properties of the films are mostly influenced by strains introduced to thin films by using different supports. Two interesting features of the electrical properties of the studied strained films were noticed: the film with the highest in-plane tensile strain showed the lowest activation energy of total conductivity, whereas the film with the lowest strain showed the highest value of total conductivity.

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Effect of Nano-Clays on the Lubricity of Drilling Fluids

Volume 4: 21st Design for Manufacturing and the Life Cycle Conference; 10th International Conference on Micro- and Nanosystems ◽

10.1115/detc2016-59368 ◽

2016 ◽

Author(s):

Jamil Abdo ◽

Hamed Al-Sharji

Keyword(s):

Electrical Properties ◽

Rheological Properties ◽

Axial Force ◽

Drilling Fluids ◽

Structure And Morphology ◽

Mechanical And Electrical Properties ◽

Force Transfer ◽

Water Based ◽

The Stability

In this study, nano-sepiolite (NSP) was synthesized, dispersed and used as a replacement for regular additives in water-based drilling fluids to enhance its lubricity. Due to its structure and morphology the suspended sepiolite nanoparticles is expected to enhance the stability against segmentation along with better thermal, mechanical and electrical properties. The morphology of the nano-modified drilling fluids and the dispersion of the nano-sepiolite are characterized using XRD and SEM. The influences of various sizes and compositions of the NSP on the stability of drilling fluids on HTHP conditions are investigated. Results revealed that the drilling fluids lubricity and the drillstring axial force transfer were significantly improved by using NSP in the base drilling fluids. The investigations showed that the lubricity and rheological properties of the nano-modified drilling fluids depend on the size and composition of the NSP additive. The studies were performed on normal and HTHP conditions.

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An Insight on the Texture and Electrical Properties of Tomato Ketchup on a Temperature Scale

Handbook of Research on Manufacturing Process Modeling and Optimization Strategies - Advances in Logistics, Operations, and Management Science ◽

10.4018/978-1-5225-2440-3.ch019 ◽

2017 ◽

pp. 399-417

Author(s):

Indu Yadav ◽

Suraj Kumar Nayak ◽

Preeti Madhuri Pandey ◽

Dibyajyoti Biswal ◽

Arfat Anis ◽

...

Keyword(s):

Electrical Properties ◽

Stress Relaxation ◽

Equivalent Circuit ◽

Incubation Temperature ◽

Mechanical Stability ◽

Electrical Equivalent Circuit ◽

Mechanical And Electrical Properties ◽

Tomato Ketchup ◽

Lower Temperature ◽

The Stability

The current study delineates the effect of incubation temperature on mechanical and electrical properties of ketchup. The analysis was done in the temperature range of 5oC and 25oC. Microstructure analysis of ketchup suggested the presence of cell wall components. Mechanical properties of ketchup were analyzed by spreadability and stress relaxation studies. Electrical properties of ketchup were analyzed by measuring the impedance in the frequency range of 100 Hz and 15 KHz. Spreadability study showed a higher firmness and cohesiveness in samples incubated at a lower temperature. The stress relaxation study suggested that inherent mechanical stability of the samples reached a critical lower limit at 15oC. Stability of the electrical equivalent circuit of samples was highest at 5oC. An increase in temperature drastically compromised the stability of electrical equivalent circuit of the samples. In gist, a variation in incubation temperature of the tomato ketchup can allow modulating not only the mechanical and viscoelastic properties, but also the electrical properties of ketchup.

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Studies on Chlorinated Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3539741 ◽

1936 ◽

Vol 9 (2) ◽

pp. 311-317

Author(s):

Tatsumi Yamamoto

Keyword(s):

Water Vapor ◽

Carbon Tetrachloride ◽

Electrical Properties ◽

Beneficial Effect ◽

High Resistance ◽

High Stability ◽

Mechanical And Electrical Properties ◽

The Stability ◽

Short Time ◽

Experimental Stage

Abstract 1. In the chlorination of rubber, the products have different combined chlorine contents which depend on the time of chlorination, but the final chlorination product seems to be C10H13Cl7, i. e., contains 64.7 per cent of chlorine. The rubber molecules disaggregate with advancing chlorination and the viscosities diminish. Accordingly the viscosity of rubbers containing the same chlorine contents vary with different conditions of preparation. 2. The properties of chlorinated rubbers vary with differences in their combined chlorine content; for a product to be thermostable and have high resistance to chemicals, it must contain over 60 per cent of chlorine. 3. The best method is to dissolve the pale crepe or F. A. Q. sheet in carbon tetrachloride and pass chlorine through the solution continuously while heating at 70–80°, with agitation. The reaction product is then separated from the solvent by distillation until the last trace of the solvent is removed, and is then washed with water free from acid impurities. 4. Chlorinated rubber has a high resistance to acids and alkalies and, above all, the permeability of films to water vapor is less than that of benzylcellulose. Moreover, chlorinated rubber is not explosive, and burns with difficulty. 5. The stability of four commercial products was studied, and an imported sample which had high stability was found to contain a stabilizer. Among various stabilizers tested, urea had the most beneficial effect. 6. As to the value of chlorinated rubber for varnish, there are many reports, and it is still in an experimental stage; but it has many properties which give the hope that it may be used as a special varnish after further studies by manufacturers and consumers. 7. By molding powdered chlorinated rubber under pressure and heat, a plastic which was easily removed in a short time was made. Its mechanical and electrical properties were tested and it gave attractive products with many pigments. Chlorinated rubber can be used as substitutes for plastics such as Bakelite or ebonite.

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Influence of reduction conditions of NiO on its mechanical and electrical properties

Journal of Electrochemical Science and Engineering ◽

10.5599/jese.220 ◽

2016 ◽

Vol 6 (1) ◽

pp. 113 ◽

Cited By ~ 3

Author(s):

Yehor Brodnikovskyi ◽

Bogdan Vasyliv ◽

Viktoriya Podhurska ◽

Mariusz Andrzejczuk ◽

Nikkia McDonald ◽

...

Keyword(s):

Electrical Conductivity ◽

Electrical Properties ◽

Structural Changes ◽

Reduction Stage ◽

Mechanical And Electrical Properties ◽

Before And After ◽

Mechanical Durability ◽

And Performance ◽

The Impact ◽

Volume Decrease

Yttria stabilized zirconia with a nickel catalyst (Ni-YSZ) is the most developed, widely used cermet anode for manufacturing Solid Oxide Fuel Cells (SOFCs). Its electro-catalytic properties, mechanical durability and performance stability in hydrogen-rich environments makes it the state of the art fuel electrode for SOFCs. During the reduction stage in initial SOFC operation, the virgin anode material, a NiO-YSZ mixture, is reduced to Ni-YSZ. The volume decrease associated with the change from NiO-YSZ to Ni-YSZ creates voids and causes structural changes, which can influence the physical properties of the anode. In this work, the structural, mechanical and electrical properties of NiO samples before and after reduction in pure H2 and a mixture of 5 vol. % H2-Ar were studied. The NiO to Ni phase transformations that occur in the anode under reducing and Reduction-Oxidation (RedOx) cycling conditions and the impact on cell microstructure, strength and electrical conductivity have been examined. Results show that the RedOx treatment of the NiO samples influence on their properties controversially, due to structural transformation (formation of large amount of fine pores) of the reduced Ni. It strengthened the treated samples yielding the highest mechanical strength values of 25.7 MPa, but from another side it is resulting in lowest electrical conductivity value of 1.9×105 S m-1 among all reduced samples. The results of this investigation shows that reduction conditions of NiO is a powerful tool for influence on properties of the anode substrate.

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Protein-induced conformational changes in 16S rRNA during assembly of the Escherichia Coli 30S ribosomal subunit: A STEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128833 ◽

1987 ◽

Vol 45 ◽

pp. 910-911

Author(s):

M. Boublik ◽

V. Mandiyan ◽

J.F. Hainfeld ◽

J.S. Wall

Keyword(s):

16S Rrna ◽

Conformational Changes ◽

Ribosomal Proteins ◽

Structural Changes ◽

Ribosomal Subunit ◽

Compact Structure ◽

E Coli ◽

Freeze Dried ◽

16S Rna ◽

30S Subunit

The aim of this study is to understand the mechanism of 16S rRNA folding into the compact structure of the small 30S subunit of E. coli ribosome. The assembly of the 30S E. coli ribosomal subunit is a sequence of specific interactions of 16S rRNA with 21 ribosomal proteins (S1-S21). Using dedicated high resolution STEM we have monitored structural changes induced in 16S rRNA by the proteins S4, S8, S15 and S20 which are involved in the initial steps of 30S subunit assembly. S4 is the first protein to bind directly and stoichiometrically to 16S rRNA. Direct binding also occurs individually between 16S RNA and S8 and S15. However, binding of S20 requires the presence of S4 and S8. The RNA-protein complexes are prepared by the standard reconstitution procedure, dialyzed against 60 mM KCl, 2 mM Mg(OAc)2, 10 mM-Hepes-KOH pH 7.5 (Buffer A), freeze-dried and observed unstained in dark field at -160°.

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Effect of drying methods of alumina powder and grapheme oxide mixture on the mechanical and electrical properties of sintered composites obtained by spark plasma sintering

Perspektivnye Materialy ◽

10.30791/1028-978x-2018-1-74-82 ◽

2018 ◽

Author(s):

P. V. Fokin ◽

◽

N. W. Solis Pinargote ◽

E. V. Kuznetsova ◽

P.Y. Peretyagin ◽

...

Keyword(s):

Electrical Properties ◽

Spark Plasma Sintering ◽

Drying Methods ◽

Alumina Powder ◽

Oxide Mixture ◽

Mechanical And Electrical Properties ◽

Plasma Sintering ◽

Spark Plasma

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Study of mechanical and electrical properties of AlMgSi alloys

Annales de Chimie Science des Matériaux ◽

10.3166/acsm.35.59-69 ◽

2010 ◽

Vol 35 (1) ◽

pp. 59-69 ◽

Cited By ~ 4

Author(s):

Fares Serradj ◽

Rebal Guemini ◽

Hichem Farh ◽

Karim Djemmal

Keyword(s):

Electrical Properties ◽

Mechanical And Electrical Properties

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Influence of Ascorbic Acid on the Structure and Function of Alpha-2- macroglobulin: Investigations using Spectroscopic and Thermodynamic Techniques

Protein and Peptide Letters ◽

10.2174/0929866526666191002113525 ◽

2020 ◽

Vol 27 (3) ◽

pp. 201-209

Author(s):

Syed Saqib Ali ◽

Mohammad Khalid Zia ◽

Tooba Siddiqui ◽

Haseeb Ahsan ◽

Fahim Halim Khan

Keyword(s):

Ascorbic Acid ◽

Conformational Changes ◽

Structural Changes ◽

The Body ◽

Titration Calorimetry ◽

Spectroscopic Techniques ◽

Human Beings ◽

Plasma Ascorbic Acid ◽

Dietary Antioxidant ◽

And Function

Background: Ascorbic acid is a classic dietary antioxidant which plays an important role in the body of human beings. It is commonly found in various foods as well as taken as dietary supplement. Objective: The plasma ascorbic acid concentration may range from low, as in chronic or acute oxidative stress to high if delivered intravenously during cancer treatment. Sheep alpha-2- macroglobulin (α2M), a human α2M homologue is a large tetrameric glycoprotein of 630 kDa with antiproteinase activity, found in sheep’s blood. Methods: In the present study, the interaction of ascorbic acid with alpha-2-macroglobulin was explored in the presence of visible light by utilizing various spectroscopic techniques and isothermal titration calorimetry (ITC). Results: UV-vis and fluorescence spectroscopy suggests the formation of a complex between ascorbic acid and α2M apparent by increased absorbance and decreased fluorescence. Secondary structural changes in the α2M were investigated by CD and FT-IR spectroscopy. Our findings suggest the induction of subtle conformational changes in α2M induced by ascorbic acid. Thermodynamics signatures of ascorbic acid and α2M interaction indicate that the binding is an enthalpy-driven process. Conclusion: It is possible that ascorbic acid binds and compromises antiproteinase activity of α2M by inducing changes in the secondary structure of the protein.

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