scholarly journals DEVELOPMENT OF THE COMPONENT COMPOSITION OF THE BIODEGRADABLE LIQUID LUBRICANT FOR SAW CHAINS

2021 ◽  
Vol 3 (56) ◽  
pp. 70-82
Author(s):  
Viktor I. ZHORNIK ◽  
◽  
Andrey V. ZAPOLSKY ◽  
Anton V. IVAKHNIK ◽  
Alexander M. PARNITSKY ◽  
...  
Keyword(s):  
Kinematic Viscosity ◽  
Viscosity Index ◽  
Component Composition ◽  
Sedimentation Stability ◽  
Refined Oil ◽  
Group Iii ◽  
Liquid Lubricant ◽  
Calcium Sulfonate ◽  
Optimization Parameters ◽  
The Stability

The procedure of working out of the component composition of the biodegradable liquid lubricant for the saw chains is shown. The experimental statistical mathematical model is developed for the optimization of the formulation of the main base taking into account the necessary viscosity and temperature parameters. At the same time the kinematic viscosity of the base body at the temperature of 40 °C and its pure point are chosen as the optimization criteria and the following three factors are used as the optimization parameters: the content of vegetable (rapeseed) oil in the composition, the viscosity of mineral oil at the temperature of 40 °C and the content of an adhesive additive in the base composition. The component composition of the lubricant is adjusted to achieve the required level of tribological properties of the saw chain oil and to ensure the stability of all its characteristics during storage (at least 12 months) and operation at a given level of biodegradability (at least 90 %). In particular, the biodegradable calcium sulfonate grease OIMOL KSC BIO was selected as an additive to improve tribological parameters. The special adhesive additive for vegetable oils of the Petrolad 484BD brand is used to increase the sedimentation stability, and the highly refined oil of group III according to the API standard is recommended to use as a mineral component. The developed lubricant has the following characteristics: density at 15 °C — 926 kg/m3, kinematic viscosity at 40 °C — 47.3 mm2/s, kinematic viscosity at 100 °C — 9.9 mm2/s, viscosity index — 202, pour point — –28 °C, flash point — 272 °C, critical load — 872 N, welding load — 1,600 N, wear index at 200 N — 0.39 mm, biodegradability — 93 %.

scholarly journals Development of beverage technology for athletes with the addition of whey proteins

2020 ◽  
Vol 22 (94) ◽  
pp. 61-65
Author(s):  
O. Krasulya
Keyword(s):  
Whey Proteins ◽  
Viscosity Index ◽  
Experimental Studies ◽  
Component Composition ◽  
The Body ◽  
Theoretical Research ◽  
Whey Protein Concentrate ◽  
Model Sample ◽  
The Stability ◽  
Positive Effect

The article substantiates the relevance of developing a new drink technology for sports nutrition. The combination of milk base has an obvious positive effect on the body and enrichment with the necessary plant components. According to the formula of balanced nutrition of athletes engaged in strength sports, the daily amount of necessary macronutrients was calculated. The aim of the work was to develop a milk drink with nutrients. Their content in a portion of 500 g will cover the daily requirement by more than 10 %. Taking into account theoretical research, the component composition of the drink for athletes is substantiated. The expediency of adding whey protein concentrate obtained by ultrafiltration has been proved. According to the results of experimental studies of the dynamic viscosity index, a rational amount and type of carbohydrate component in the beverage has been established. With the addition of maltodextrin in the amount of 8 %, a viscous-fluid consistency of the model sample is observed. Тhe recommended limit on the amount of carbohydrates in beverages for athletes, namely an average of 10…12 %, taking into account the lactose content in milk-based about 4.0…4.5 %. The addition of soybean oil to the composition of the drink recipe for athletes is justified. A rational amount of lecithin emulsifier has been established to ensure the stability of the emulsion of the finished product. The composition of the milk drink recipe for athletes is given, which additionally includes a multivitamin premix, creatine monohydrate, dry extract of safflower leaflet, flavoring. The calculation of the nutritional and energy value of the developed drink was performed and the assessment of the satisfaction of the daily requirement for minerals and vitamins when drinking the drink in the amount of 500 g (1 serving) was performed. Consumption of the developed drink by the athlete who is engaged in power sports, in the amount of 500 g per day will provide the body with the necessary nutrients by more than 10 %.

scholarly journals Effects of photofunctionalization on early osseointegration of titanium dental implants in the maxillary posterior region: a randomized double-blinded clinical trial

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Bada Choi ◽  
Ye Chan Lee ◽  
Kyung Chul Oh ◽  
Jae Hoon Lee
Keyword(s):  
Clinical Trial ◽  
Resonance Frequency ◽  
Bone Quality ◽  
Frequency Analysis ◽  
Treated Group ◽  
Posterior Region ◽  
Resonance Frequency Analysis ◽  
Group Iii ◽  
The Stability ◽  
Double Blinded

Abstract Background This study aimed to investigate the effects of ultraviolet (UV) photofunctionalization on the stability of implants during the early phase in the posterior region of the maxilla. The study was a randomized double-blinded clinical trial. Half of the participants received conventional commercial implants while the other half received UV-irradiated implants. The surgical sites were classified into three bone quality groups (II, III, IV) based on the grayscale value measured on cone-beam computed tomography. The values obtained from resonance frequency analysis were recorded immediately after implant placement and at 4 weeks and at 4 months postoperatively. The marginal bone level of the implants was evaluated using periapical radiographs at 4 weeks, 4 months, and 1 year postoperatively. Results Fifty-seven implants placed in 34 participants were analyzed in this study. In group III, significant differences were observed in terms of the differences of resonance frequency analysis values at 4 weeks (p = 0.004) and 4 months (p = 0.017) postoperatively. In group II, the UV-treated group showed significantly lesser bone loss at 4 weeks post-operatively (p = 0.037). Conclusions Within the limitation of the present study, we concluded that UV surface treatment on implants may increase the initial stability in the region of the maxilla with poor bone quality.

On the Stability of Two Superposed Viscous-Viscoelastic (Walters B′) Fluids

2006 ◽  
Vol 129 (1) ◽  
pp. 116-119 ◽  
Author(s):  
Pardeep Kumar ◽  
Roshan Lal
Keyword(s):  
Viscous Fluid ◽  
Viscoelastic Fluid ◽  
Kinematic Viscosity ◽  
Taylor Instability ◽  
Stable Configuration ◽  
Stabilizing Effect ◽  
Unstable Configuration ◽  
Rayleigh Taylor Instability ◽  
Newtonian Viscous Fluid ◽  
The Stability

The Rayleigh-Taylor instability of a Newtonian viscous fluid overlying Walters B′ viscoelastic fluid is considered. For the stable configuration, the system is found to be stable or unstable under certain conditions. However, the system is found to be unstable for the potentially unstable configuration. Further it is found numerically that kinematic viscosity has a destabilizing effect, whereas kinematic viscoelasticity has a stabilizing effect on the system.

Physicochemical properties and tribological performance of motorbike lubricant dispersed with surface-modified WS2 nanoparticles

2019 ◽  
Vol 233 (9) ◽  
pp. 1379-1388 ◽  
Author(s):  
V Srinivas ◽  
RN Thakur ◽  
AK Jain ◽  
M Saratchandra Babu
Keyword(s):  
Physicochemical Properties ◽  
Fuel Consumption ◽  
Viscosity Index ◽  
Tribological Performance ◽  
Engine Oil ◽  
Engine Wear ◽  
Endurance Tests ◽  
The Stability ◽  
Surface Modified ◽  
Engine Components

This paper investigates the effect of dispersion of surface-modified WS2 nanoparticles on the tribological performance and physicochemical properties of motorbike lubricant. Surface-assisted WS2 nanoparticles were dispersed in motorbike engine oil and an optimum amount of surfactant for best stability of the lubricant suspension was found by investigating the changes in the physicochemical properties of lubricant. The stability analysis using light scattering techniques confirmed the stability of nanoparticles dispersed in lubricant medium and surface-modified WS2 nanoparticles remained stable for 180 days. The physicochemical properties were evaluated as per ASTM standards over a period of two months to check the state of lubricant and observable changes in the properties during this period. The tribological performance of the lubricants was assessed by conducting endurance tests on a 100 cc motor bike. The performance was evaluated by checking the wear of the engine components and fuel consumption. It was found that there were no abnormal changes in the physicochemical properties of lubricant up to a certain surfactant to nanoparticle ratio indicating its utility in automotive engines. However, if the amount of surfactant was increased beyond optimum quantity abnormal changes are seen in the viscosity index, leading to the deterioration of key lubricant properties. Lubricant dispersed with WS2 nanoparticles gave good performance characterized by the reduction in both engine wear and fuel consumption. Worn surfaces of the oil rings after the endurance test were assessed for deposits and it was found that a layer of WS2 deposited on the oil ring surface that reduced friction and wear.

scholarly journals Influence of optimal conditions of ultrasonic dispersion on the stability of suspensions of finely ground slags

2019 ◽  
Vol 265 ◽  
pp. 01017 ◽  
Author(s):  
Svetlana Samchenko ◽  
Irina Kozlova ◽  
Оlga Zemskova ◽  
Ekaterina Baskakova
Keyword(s):  
Aqueous Dispersion ◽  
Cement Composite ◽  
Cement Stone ◽  
Mechanical Mixing ◽  
Dispersion Parameters ◽  
Ultrasonic Dispersion ◽  
Sedimentation Stability ◽  
Granulated Blast Furnace Slag ◽  
The Stability ◽  
Furnace Slag

The preparation in the jet mill of finely ground slag (FGS) from the waste of metallurgical production granulated blast-furnace slag, the obtaining of slag suspensions, and the behavior of FGS particles in an aqueous dispersion medium are considered in the paper. It was found that FGS particles in the suspension form micelles of two types with negative (micelle 1) and positive (micelle 2) charges of FGS surface. To increase the aggregative and sedimentation stability of FGS particles in suspensions, studies were carried out using ultrasonic dispersion. The results of investigations on the detection of optimal dispersion parameters for slag suspensions are presented. It was found that in the absence of temperature control, the process of coagulation of slag particles is accelerated and aggregative and sedimentation stability of suspensions of FGS is reduced. The slag particles in the suspension form aggregates that lead to a deterioration of the strength characteristics of the cement stone using suspensions of FGS. Optimal parameters of ultrasonic dispersion of slag suspensions are established: the frequency of ultrasonic vibrations is equal to 44 kHz; the dispersion temperature is 25 ± 2 °C; the dispersion time is 15 min. It was found that the application of ultrasonic dispersion to slag suspensions with the observance of dispersion conditions can increase the aggregative and sedimentation stability of FGS suspension by 2-3 times in comparison with the mechanical mixing of suspensions. The strength of samples with suspensions of FGS prepared using UST under the recommended dispersing conditions increased by 19 to 39% in the first day; for 28 days of hardening - by 19 - 36%, which allows using slag suspensions in the production of cement composite materials and concretes based on them.

scholarly journals DEVELOPMENT OF THE METHOD AND OPTIMIZATION OF THE COMPOSITION AND MODES OF OBTAINING THE BIODEGRADABLE GREASE WITH THE LITHIUM-CALCIUM THICKENER

2021 ◽  
Vol 2 (55) ◽  
pp. 60-72
Author(s):  
V.I. Zhornik ◽  
◽  
A.V. Zapolsky ◽  
A.V. Ivakhnik ◽  
A.M. Parnitsky ◽  
...  
Keyword(s):  
Dispersion Medium ◽  
Prolonged Exposure ◽  
Component Composition ◽  
American Petroleum Institute ◽  
Treatment Temperature ◽  
Reaction Mass ◽  
Green Economy ◽  
Group Iii ◽  
Dropping Point ◽  
Lithium Hydroxide Monohydrate

It is noted that the development of biodegradable lubricants is an integral part of the development of a modern “green” economy. The distinctive features of the proposed method are described for producing a biodegradable grease on a mixed lithium-calcium thickener, providing for the introduction of alkaline initial components of the dispersed phase (lithium hydroxide monohydrate and calcium hydroxide) into the reaction mass not in the form of their aqueous solutions, but in a powdery state, and the exception of prolonged exposure to water and high temperature on a component of a dispersion medium of plant origin (rapeseed oil) in the process of lubricant synthesis. Along with this, it was proposed to use a highly refined oil of group III according to the API (American Petroleum Institute) standard as a mineral component of the dispersion medium. This provides, in aggregate, the higher stability of the rheological and tribological characteristics of the grease (for at least 12 months) at a given level of biodegradability. The experimental-statistical mathematical model of the process of obtaining the biodegradable lithium-calcium grease is developed, which makes it possible to determine the parameters of the component composition (the content of the mixed lithium-calcium thickener in the grease and the content of lithium stearate in the mixed thickener) and the synthesis modes (the heat treatment temperature of the reaction mass) to achieve the given level of the main characteristics of the finished grease (penetration, dropping point) while ensuring its biodegradability of at least 80 %.

scholarly journals DISCURSIVE TYPES OF RHYMES

2019 ◽  
pp. 293-305
Author(s):  
L. Movchun
Keyword(s):  
Creative Process ◽  
Component Composition ◽  
World Culture ◽  
Its Analysis ◽  
The Stability ◽  
Contextual Parameter

The article raises the problem of the rhyme classification, in particular, in the matter of supplementing it with actual parameters. Interpretation of the rhymed text as a creative process determines its analysis in two diametrically opposite aspects: individualauthorial and general-cultural. In the discourse of author’s creativity, the rhyme is analyzed in terms of the stability of the component composition, the compliance with the completed text, the mandatory employment. In the discourse of national and world culture, rhymes are analyzed on the basis of intertextuality. The rhyme transformation is described in the direction from the original rhyming compound to the result of its development in the new text. Intertextual rhymes are analyzed according to their perceptual potential, the accuracy of the reproduction of the original rhyme, as well as the contextual parameter.

scholarly journals Effect of Selected Stabilizers and Processing Aids on the Stability of a Double Emulsion Encapsulating Bitter Gourd Extract

2021 ◽  
Author(s):  
Urmila Choudhary ◽  
Latha Sabikhi
Keyword(s):  
Double Emulsion ◽  
Gum Arabic ◽  
Sodium Caseinate ◽  
Bitter Gourd ◽  
Whey Protein Concentrate ◽  
Physical Parameters ◽  
Sedimentation Stability ◽  
Double Emulsions ◽  
The Stability ◽  
Emulsion Matrix

Effect of three variables in differing concentrations [NaCl (3-5%), polyglycerol polyricinoleate (PGPR) (2-4%) and dairy protein-polysaccharide complexes (Whey protein concentrate(WPC-80)-gum Arabic(GA) and sodium caseinate(SC)-gum Arabic in 1:2 ratio)] on the stability of W1/O/W2 emulsion matrix that was used to encapsulate bitter gourd extract was evaluated. The double emulsion matrix was characterized by apparent viscosity, zeta potential, turbidity and sedimentation stability by visual appearance. The physical parameters of the double emulsion matrix were very highly significantly (p < 0.001) affected by all variables such as the concentration of salt, PGPR and complex (WPC-GA and SC-P) as well as their interactions. The double emulsions prepared with WPC-GA became unstable immediately after preparation or after one day of preparation. SC-GA stabilized double emulsions were found more stable than WPC-GA stabilized emulsions. A double emulsion containing 5% NaCl, 2% PGPR and 16.5% SC-GA were found most stable (10 days at 37°C) in comparison to other combinations used.

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