Preparation and Properties of Layered SiC-Graphene Composites for EDM

Three and five-layered silicon carbide-based composites containing 0, 5, and 15 wt.% of graphene nanoplatelets (GNPs) were prepared with the aim to obtain a sufficiently high electrical conductivity in the surface layer suitable for electric discharge machining (EDM). The layer sequence in the asymmetric three-layered composites was SiC/SiC-5GNPs/SiC-15GNPs, while in the symmetric five-layered composite, the order of layers was SiC-15GNPs/SiC-5GNPs/SiC/SiC-5GNPs/SiC-15GNPs. The layered samples were prepared by rapid hot-pressing (RHP) applying various pressures, and it was shown that for the preparation of dense 3- or 5-layered SiC/GNPs composites, at least 30 MPa of the applied load was required during sintering. The electrical conductivity of 3-layered and 5-layered composites increased significantly with increasing sintering pressure when measured on the SiC surface layer containing 15 wt.% of GNPs. The increasing GNPs content had a positive influence on the electrical conductivity of individual layers, while their instrumented hardness and elastic modulus decreased. The scratch tests confirmed that the materials consisted of well-defined layers with straight interfaces without any delamination, which suggests good adhesion between the individual layers.

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Determination of the transverse shear stress in layered composites

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-2-44-53 ◽

2020 ◽

Vol 86 (2) ◽

pp. 44-53

Author(s):

Yu. I. Dudarkov ◽

M. V. Limonin

Keyword(s):

Shear Stress ◽

Transverse Shear ◽

Composite Beam ◽

Layered Composite ◽

Equivalent Model ◽

Shear Stresses ◽

Transverse Shear Stress ◽

Layered Composites ◽

Laminate Composites ◽

Transverse Shear Stresses

An engineering approach to estimation of the transverse shear stresses in layered composites is developed. The technique is based on the well-known D. I. Zhuravsky equation for shear stresses in an isotropic beam upon transverse bending. In general, application of this equation to a composite beam is incorrect due to the heterogeneity of the composite structure. According to the proposed method, at the first stage of its implementation, a transition to the equivalent model of a homogeneous beam is made, for which the Zhuravsky formula is valid. The transition is carried out by changing the shape of the cross section of the beam, provided that the bending stiffness and generalized elastic modulus remain the same. The calculated shear stresses in the equivalent beam are then converted to the stress values in the original composite beam from the equilibrium condition. The main equations and definitions of the method as well as the analytical equation for estimation of the transverse shear stress in a composite beam are presented. The method is verified by comparing the analytical solution and the results of the numerical solution of the problem by finite element method (FEM). It is shown that laminate stacking sequence has a significant impact both on the character and on the value of the transverse shear stress distribution. The limits of the applicability of the developed technique attributed to the conditions of the validity of the hypothesis of straight normal are considered. It is noted that under this hypothesis the shear stresses do not depend on the layer shear modulus, which explains the absence of this parameter in the obtained equation. The classical theory of laminate composites is based on the similar assumptions, which gives ground to use this equation for an approximate estimation of the transverse shear stresses in in a layered composite package.

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The Modification of Carbon Included Polyethylene Surface by Plasma Treatment for Metallizing Using a Low Pressure RF Discharge Plasma

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2005-0111 ◽

2005 ◽

Vol 8 (1) ◽

Author(s):

Jeou-Long Lee ◽

Chung-Ming Liu ◽

Kuen Ting ◽

Wei-Kung Cheng ◽

Takayoshi Tsuchida ◽

...

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Surface Layer ◽

Discharge Plasma ◽

Treatment Time ◽

Low Pressure ◽

Rf Discharge ◽

Nickel Layer ◽

Good Adhesion ◽

Polyethylene Surface

AbstractSurface modification of the carbon included polyethylene (semi-conductive PE) surface for metallizing using a low pressure RF discharge plasma has been carried out. The contact angle was used as a measure of the wettability of the PE surface. The roughness and the chemical bondings in PE surface layer were analized by DFM and XPS, respectively. Typical results show that the contact angle decreases from approximately 94° to below 10° after several minutes' treatment and recovers to a saturation value when it was put open to the air after treatment. The saturation value of the contact angle is smaller as the gas pressure for treatment is higher and the treatment time is longer but all are below approximately 60° which is still smaller than that of untreated. DFM and XPS results show that the surface roughness and the bondings C-O and C=O in the PE surface layer also increase with increasing the treatment time and seem to be responsible for improving the hydrophilic property of PE. After pretreatment process, nickel was coated on the PE sheet by electrodeposition method and a good adhesion between the nickel layer and the PE surface compared with that of untreated was obtained.

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The Tegument and Associated Structures of Fasciola Hepatica

Journal of Cell Science ◽

10.1242/jcs.s3-104.68.505 ◽

1963 ◽

Vol s3-104 (68) ◽

pp. 505-512

Author(s):

L. T. THREADGOLD

Keyword(s):

Electron Microscopy ◽

Surface Layer ◽

Light Microscopy ◽

Fasciola Hepatica ◽

Golgi Bodies ◽

New Knowledge ◽

Pinocytotic Vesicles ◽

The Individual ◽

And Function ◽

Internal Level

The cuticle of light microscopy is shown by electron microscopy to be a surface layer of protoplasm which is an extension of areas of nucleated protoplasm lying deep in the parenchyma. The cuticle therefore exists at two levels. The external level is syncytial, consisting of plateaux separated by branching valleys. This level contains apical pinocytotic vesicles, numerous mitochondria, endoplasmic membranes, large basal and other vacuoles, and dense spines. Tube-like evaginations from the base of the external level connect it to the individual areas of flask-shaped protoplasm which compose the internal level. Each of these areas of protoplasm contains a nucleus, great numbers of mitochondria, some vacuoles and diffuse inclusions, and the Golgi bodies. The histochemistry and function of the cuticle is discussed in the light of this new knowledge of cuticular ultrastructure, and a comparison is made between the cuticle of Cestoda and Trematoda.

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Quality of Educational Programs in Life-long Learning

Studia commercialia Bratislavensia ◽

10.2478/v10151-011-0003-2 ◽

2011 ◽

Vol 4 (13) ◽

pp. 102-110

Author(s):

Alica Lacková ◽

Marta Karkalíková

Keyword(s):

Quality Of Life ◽

Job Performance ◽

Quality Evaluation ◽

Systematic Approach ◽

Educational Programs ◽

Positive Influence ◽

Rational Approach ◽

Life Long Learning ◽

The Individual

Quality of Educational Programs in Life-long Learning The paper deals with a systematic approach to education as well as to other areas, which represents a tool ensuring that education was performed effectively and efficiently, that it had positive influence on the society and the individual and it had improved their job performance and quality of life. This rational approach to the development of educational programs, their execution and quality evaluation enables to reach strategic education aims successfully and in a way that they suit and stimulate the requirements of practice.

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Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline

Тонкие химические технологии ◽

10.32362/2410-6593-2021-16-2-138-147 ◽

2021 ◽

Vol 16 (2) ◽

pp. 138-147

Author(s):

S. A. Syrbu ◽

M. S. Fedorov ◽

E. A. Lapykina ◽

V. V. Novikov

Keyword(s):

Crystal Structure ◽

Electrical Conductivity ◽

Dielectric Constant ◽

Dielectric Properties ◽

Dielectric Anisotropy ◽

Specific Electrical Conductivity ◽

Conductivity Anisotropy ◽

Independent Molecules ◽

System Properties ◽

The Individual

Objectives. Our aim was to study the dielectric properties of the 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4’-methylaniline system and reveal how different concentrations of N-(4-n-butyloxybenzylidene)-4’-methylaniline additives affect the dielectric properties of 4-n-pentyloxybenzoic acid.Methods. System properties were investigated using polarization thermomicroscopy and dielcometry.Results. We found that dielectric anisotropy changes its sign from positive to negative at the transition temperature of the high-temperature nematic subphase to the low-temperature one. The anisotropy of the dielectric constant of N-4-n-butoxybenzylidene-4’-methylaniline has a positive value and increases as to the system approaches the crystalline phase. The crystal structure of the 4-n-pentyloxybenzoic acid contains dimers formed by two independent molecules due to a pair of hydrogen bonds. The crystal structure of N-(4-n-butoxybenzylidene)-4’-methylaniline contains associates formed by orientational interactions of two independent molecules. 4-n-Pentyloxybenzoic acid dimers (270 nm) and associates of N-4-n-butoxybenzylidene-4’- methylaniline (250 nm) proved to have approximately the identical length. Considering the close length values of the structural units of both compounds and the dielectric anisotropy sign, we assume that the N-4-n-butoxybenzylidene-4’-methylaniline associates are incorporated into the supramolecular structure of the 4-n-pentyloxybenzoic acid. The specific electrical conductivity of the compounds under study lies between 10−7 and 10−12 S∙cm−1. The relationship between the specific electrical conductivity anisotropy and the system composition in the nematic phase at the identical reduced temperature, obtained between 100 and 1000 Hz is symbatic. However, the electrical conductivity anisotropy values of the system obtained at 1000 Hz are lower compared to those obtained at 100 Hz. At N-(4-n-butoxybenzylidene)-4’-methylaniline concentrations between 30 and 60 mol %, the electrical conductivity anisotropy values are higher than those of the individual component.Conclusions. A change in the sign of the dielectric constant anisotropy of the 4-n-pentyloxybenzoic acid during nematic subphase transitions was established. We showed that the system has the highest dielectric constant anisotropy value when components have an equal number of moles. Highest electrical conductivity anisotropy values are observed when the concentration of the N-4-n-butoxybenzylidene-4᾽-methylaniline system lies between 30 and 60 mol %.

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THE EFFECT OF ENTEROSORPTION AND INTRATISSULAR ELECTROFORESIS OF ANTIBACTERIAL DRUGS ON PROGRESS OF BURN DISEASE

Kharkiv Surgical School ◽

10.37699/2308-7005.2.2020.36 ◽

2020 ◽

pp. 188-192

Author(s):

B. V. Petriuk ◽

I. I. Blуk ◽

О. V. Rоtаr ◽

L. P. Khomko ◽

T. A. Petriuk ◽

...

Keyword(s):

Electrical Conductivity ◽

Thermal Damage ◽

Positive Influence ◽

Reparative Regeneration ◽

Comprehensive Treatment ◽

Antibacterial Drugs ◽

Average Mass ◽

Thermal Burns ◽

Burn Disease ◽

Extensive Burns

Summary. The purpose of our research was to explore the appropriateness of combined usage of enterosorption amplification and intratissular electrophoresis (ITE) of antibiotics in cases of substantial thermal burns. The effect of intratissular electrophoresis (ITE) of antibacterial drugs and enterosorption was studied in 22 patients with dermal thermal burns from 28 to 54 % of their body surface. ITE of antibiotics started from the 3–4 day applying the direct current with density 0,03-0,05 mAh/cm² for 60 min. by the «POTOK-1» device. The authors determined the intoxication degree based on the leukocyte index, the number of average mass molecules and blood plasma electrical conductivity. Also, they observed the course of wound process, conducted bacteriological and cytological researches of the burn wounds in dynamics on 1–3, 6–7, 13–14 and 19–21 days of the burn disease progress. It was found that enterosorption usage in the comprehensive treatment of burn disease allows not only to reduce the level of endogenous intoxication but also to provide an indirect optimizing impact on the progressing of the wound process in the zone of thermal damage, stimulate the reparative regeneration. In the cases with extensive burns, combined usage of the enterosorption detoxification by Enterosgel with the ITE of antibacterial drugs contribute more qualitative positive influence on the wound process and burn disease in general.

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THE INFLUENCE OF INTENTION UTILIZATION AND USE OF ACCOUNTING SOFTWARE ON INDIVIDUAL PERFORMANCE: UNIFIED THEORY APPROACH OF ACCEPTANCE AND USE OF TECHNOLOGY (UTAUT) MODEL

Jurnal Akuntansi ◽

10.33369/j.akuntansi.6.1.85-100 ◽

2019 ◽

Vol 6 (1) ◽

pp. 85-100

Author(s):

Madani Hatta ◽

Fenny Marietza ◽

Rewa Yoke Desthomson

Keyword(s):

Social Influence ◽

Individual Performance ◽

Positive Influence ◽

Theory Approach ◽

Performance Expectation ◽

Use Of Technology ◽

Accounting Software ◽

Facilitating Conditions ◽

The Individual ◽

Significant Positive Influence

This study aims to determine the influence of utilization intention and use accounting software for individual performance by using a model unifiedtheory of acceptance and use of technology (UTAUT) consisted of performance expectation, effort expectation, social influence, facilitating conditions, the intention of the use of accounting software, the useof accounting software, and the individual performance. The sample in this study were 61 employees of the banking company in the city of Bengkulu who use accounting software in their working activity. The results showed that the performance expectation has significant positive influence to intention utilization accounting software, effort expectation has significant positive influence to the intention utilization accounting software, social influence has significant positive influence to the use of accounting software intention, facilitating condition has significant positive influence to the use of accounting software, accounting software utilization intention has significant positive influence to the use of accounting software and the use of accounting software has positive influence to the performance of the individual.Key words : Performance Expectation, Effort Expectation, Social Influence, The Facilitating Conditions, Intention Utilization, Use of Accounting Software, UTAUT.

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Printability and Properties of Conductive Inks on Primer-Coated Surfaces

International Journal of Polymer Science ◽

10.1155/2019/3874181 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8

Author(s):

Hector R. Mendez-Rossal ◽

Gernot M. Wallner

Keyword(s):

Electrical Conductivity ◽

Surface Roughness ◽

Electrical Resistivity ◽

Screen Printing ◽

Good Adhesion ◽

Laser Confocal Microscopy ◽

Conductive Inks ◽

Coated Metal ◽

Coated Surfaces ◽

Resistivity Testing

Conductive inks’ performance is affected by the printing conditions and the substrate’s properties. In this study, one graphite-, one polymer-, and two silver-based conductive inks were printed on four primer-coated metal substrates by screen printing. The compatibility and wettability between the inks and the primers were evaluated by infrared spectroscopy and surface energy measurements. The printed structures were characterized by laser confocal microscopy, peel-off tape testing, and four-point probe electrical resistivity testing. In general, silver inks exhibited the best performance in terms of printability and electrical conductivity. The graphite ink presented the worst printing, adhesion, and functional properties. The polymer-based ink revealed poor wettability but good adhesion and functionality. The surface roughness, energy, and polarity of the primer coating had no significant influence on the electrical conductivity of the printed inks.

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What Have the Bach Passions Ever Done for Jewish–Christian Relations?

European Judaism ◽

10.3167/ej.2020.530114 ◽

2020 ◽

Vol 53 (1) ◽

pp. 105-119

Author(s):

Alexandra Wright

Keyword(s):

Positive Influence ◽

Musical Expression ◽

Life And Death ◽

The Individual ◽

Universal Themes

Both the texts and music of Bach’s St Matthew and St John Passions portray the Jews in deeply negative ways, baying for the blood of Christ. While there are strong arguments against seeing these works as having any kind of positive influence on Jewish–Christian relations, there is also an argument for examining the different layers of texts – from the Gospels to contemporary Lutheran poetry – as well as diverse musical expression in both works in order to elicit and understand profound, universal themes of sin and repentance, confession and forgiveness, life and death. Public performances of the Passions need to be undertaken responsibly with detailed programme notes and talks that draw out the journey of the individual worshipper and tackle the difficult problems of the Gospel texts and the music.

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