Influence Of Mixture Composition Research Articles

Influence of Mixture Composition on Electrophysical Parameters and Emission Spectra of Trifluoromethane Plasma with Oxygen and Argon

Influence of Mixture Composition on Electrophysical Parameters and Emission Spectra of Trifluoromethane Plasma with Oxygen and Argon

Influence of Mixture Composition on Electrophysical Parameters and Emission Spectra of Tetrafluoromethane and Trifluoromethane Plasma with Nitrogen

Influence of Mixture Composition on Electrophysical Parameters and Emission Spectra of Tetrafluoromethane and Trifluoromethane Plasma with Nitrogen

Influence of Mixture Composition on Electrophysical Parameters and Emission Spectra of Tetrafluoromethane and Trifluoromethane Plasma with Nitrogen

The influence of the mixture composition on the electrophysical parameters and plasma emission spectra of mixtures of tetrafluoromethane and trifluoromethane with nitrogen under dc glow discharge conditions has been analyzed. It has been established that the reduced electric field strength changes nonlinearly with an increase in the proportion of the second gas in both mixtures. The reduced intensity of atomic fluorine emission in the CF4/N2 mixture is shown to pass through a maximum at a nitrogen volume fraction of 0.2, whereas a monotonic change in this dependence is observed for the CHF3/N2 mixture. The reduced emission intensities of CF2 radicals decrease monotonically with an increase in the nitrogen fraction in both mixtures.

Properties of Fly Ash-Slag-Based Geopolymer Concrete with Low Molarity Sodium Hydroxide

Most geopolymer concrete is produced using low-calcium fly ash and cured at high drying temperatures. Additionally, the activator is prepared with a sodium hydroxide (SH) solution of high molarity. This research proposes using a low molarity SH solution to produce fly ash-slag-based geopolymer concrete cured at room temperature. The properties to be investigated include workability, water absorption, and compressive strength. The influence of mixture composition, i.e., slag content, sodium silicate to sodium hydroxide (SS/SH) ratio, and alkaline activator to binder (Al/Bi) ratio on those properties is of interest. The slag substituted fly ash at 10, 20, 30, 40, and 50% replacement levels. The SS/SH ratio is 1.0, 1.5, and 2.0, with the SH molarity determined at 2M. The Al/Bi ratio is 0.40, 0.45, and 0.50. The results show that a higher percentage of slag reduces slump and water absorption but increases the compressive strength of the geopolymer concrete. The mixtures suitable for use are at the percentages of slag 20, 30, and 40%. An increase in the SS/SH ratio decreases the slump and water absorption. Geopolymer concrete with an SS/SH ratio of 1.5 gives maximum compressive strength compared to the other ratios. Increasing the ratio of Al/Bi increases the workability of geopolymer concrete. At an Al/Bi ratio of 0.45, the compressive strength is maximum and the water absorption is minimum. The recommended mix design in terms of workability, water absorption, and compressive strength of geopolymer concrete is a mixture with slag contents of 20, 30, and 40%, a SS/SH ratio of 1.0 and 1.5, and an Al/Bi ratio of 0.45 and 0.50. Doi: 10.28991/CEJ-2023-09-02-010 Full Text: PDF

Influence of Mixture Composition Between Soybean Oil and Diesel Fuel on Characteristic of Droplets Combustion

<p class="02abstracttext">Depleting oil reserves has encouraged many researchers to search for new energy resources. Of many alternatives, soybean oil has been proposed as biodiesel. In this study, influence of mixture composition of soybean oil and diesel fuel on the droplet combustion characteristics was investigated. These characteristics included Ignition delay time, fire visualization, flame temperature and burning rate. The mixture comprises 10 to 50% soybean oil while the rest are Pertamina Dex diesel fuel. The study shows that flash point temperature, ignition delay time and burning rate increase as soybean oil content increases. In contrary, the flame height decreases with increasing soybean oil content.</p>

Influence of Mixture Composition and Compaction Pressure of Briquette Made from Ironwood (Eusideroxylon Zwageri) Charcoal and Gelam (Melaleuca Cajuputi ) on Combustion Characteristic

<p class="02abstracttext">In recent few years, many works have been dedicated to search for new source of renewable energy. In this study, new source of renewable energy is based in the briquette made from mixture of ironwood (Eusideroxylon zwageri) powder and gelam (Melaleuca leucadendron) wood powder. The mixture was carbonized at temperature of 500 <sup>o</sup>C ± 10 <sup>o</sup>C for 120 minutes. The size of the particles used was 50 mesh while the ratio between wood powder adhesives, i.e. starch powder, used in the study was 1:1. The composition variations between ironwood charcoal and gelam were 100% ironwood charcoal powder and 0% gelam, 70%: 30%, 50%: 50%, 30%: 70%, 0% ironwood: 100% gelam. The compaction pressure during briquette production was varied at 100 kg/cm<sup>2</sup>, 125 kg/cm<sup>2</sup> and 150 kg/cm<sup>2</sup>. The highest combustion temperature at 205 <sup>o</sup>C occurred in the specimen with composition of 30% ironwood powder and 70% gelam wood powder with compaction pressure of 100 kg/cm<sup>2</sup>. The longest burning duration 140 minutes (2 hours 20 minutes) occurred at composition of 50% ironwood powder and 50% gelam wood powder at compaction pressure of 150 kg/cm<sup>2</sup>. The fastest initial ignition time was 7 minutes and occurred for mixture with composition of 70% ironwood powder and 30% gelam wood powder at compaction pressure of 125 kg/cm<sup>2</sup>.</p>

Influence of mixture composition on the properties of foamed concrete

Abstract Foamed concrete is a revolutionary and an adaptable construction material, which consists of cement and fine aggregate mixed with air bubbles to a minimum of 20%. Slender sections can be designed by the use of these foamed concrete blocks, which are light in weight as well as with densities less than 1800 Kg/m3. At the same time, foamed concrete blocks possesses good thermal insulation properties, which makes it more acceptable in the construction industry. In this his paper, the advancement of Foamed Concrete with the use of fly ash as a substitute for cement is described in detail. It has been observed that the compressive strength has increased by 14.15% by the addition of fly ash at the rate of 40% by weight of cement. Hence, it is established that foamed concrete blocks of comparable strength as that of existing bricks/hollow/solid concrete blocks of similar or lower densities possessing thermal insulation properties can be produced with the use of fly ash as substitute for cement.

Influence of mixture composition on fresh concrete workability for ballastless track slabs

There are several factors that affect the fresh concrete workability: water demand and composition of Portland cement, properties of fine and coarse aggregates, presence of superplasticizer and others admixtures, etc. Influence of quantity and fineness of ground quartz additives as well as polycarboxylate-based superplasticizer amount on workability of fresh concrete was studied in the paper. The properties of fresh mixture (slump) and hardened concrete (compressive strength at the age of 24 hours, 28 and 360 days) were estimated. Enhancing the fresh concrete workability using fine ground quartz sand was stated. Savings of superplasticizer per 1 m3 of slab concrete and 1 km of the ballastless track were calculated.

Thermodynamics Cycle of Gas-Cooled Fast Reactor

Abstract This paper deals with the thermo-hydraulic aspect of gas cooled fast 4 generation reactor. The paper is focused on the comparison of direct and indirect strategy of thermodynamics cycle of helium cooled reactor from the thermodynamics and turbomachinary point of view. The analyses respect pressure looses at all major part of the equipment - reactor, heat exchanger, pipe lines, etc. The compressor and gas turbines efficiency are includes in calculation as well. The working fluid in primary circuit is helium. In the secondary circuit a mixture of helium and nitrogen is considered. The Cycle characteristic point and efficiency calculation reflects mixture properties of the real gas. Calculation point out the influence of mixture composition on the basic structural parameters of the turbines, compressor and heat exchangers. Thermodynamics cycle efficiency, specific heat input/output, heat flux and cycle work will be presented as characteristic parameters.

Rheological and thermal properties of mixtures of hydroxyl-terminated polybutadiene and plasticizer (Rapid communication)

Mixtures of hydroxyl-terminated polybutadiene (HTPB) and dioctyladipate (DOA) as a plasticizer, which after crosslinking are applied as binders in heterogeneous propellants, were studied.The influence of mixture composition on rheological and thermal properties, important from technological and utility viewpoint were specified. The temperature dependence of prepared mixtures viscosity were studied. Systems were subjected to crosslinking and values of pot life (tpl) were determined. It was stated that tpl rose with increasing plasticizer content. Differential scanning calorimetry and thermogravimetry techniques were used toanalyze thermal stability of mixtures. It was concluded that applied component scould not decompose in the temperature range of 290–350 K and studied mixtures did not cause the hazard of thermal explosion.

Exploring the interactions in binary mixtures of polyelectrolytes: Influence of mixture composition, concentration, and temperature on counterion condensation

The counterion condensation in the binary mixtures of like-charged polyelectrolytes with two different molecular weights, where both are negatively charged, has been studied by conductance measurement in aqueous medium. Sodium polystyrenesulfonate with two different chain lengths have been selected as model polyelectrolyte and the investigation has been carried out in the absence of any added salt. The specific conductance-polyelectrolyte concentration data were analyzed in the light of the scaling argument for the conformation of polyion chains in solutions to quantify the fractions of free counterions. Effects of polyelectrolyte concentration, molecular weights of the components of the mixture, and solution temperature on the condensation of counterions have been investigated to explore polyion–counterion interaction, and inter- and intra-chain interactions in these polyelectrolyte mixtures. This investigation revealed that the extent of counterion condensation is significantly influenced by the mixture composition, the polyelectrolyte concentration and the temperature. Evaluation of the polyion transference numbers provided important information as to the direction of the motion of the counterions under the action of the applied electric field.

The influence of mixture composition, adhesion promotor and compaction degree on the groove stability of grooved Marshall asphalt

After the first rehabilitation of runway 07R/25L in 2015, runway 01/19 was reconstructed in the summer of 2016, as part of a cycle where all runway pavements at Brussels airport are completely renovated each thirty years. The top layer is a Marshall asphalt with a polymer modified bitumen. To optimize the water drainage the central part of the runway (47 m wide) is grooved instead of applying an anti-skid layer. In this paper the focus is on the durability of the grooved top layer. Two different Marshall asphalt mixtures with a different maximum granulate size (10 mm or 14 mm) are compared, both in the laboratory and in a full-scale trial. In the laboratory the resistance against rutting and raveling are investigated for both mixtures with and without adhesion promotor, which did not show a positive effect. In the full-scale trial the compactability and impact of both a longer curing period and a variation in the degree of compaction on the groove stability is investigated for both mixtures using a heavy truck. No visual differences could be found except in areas which were undercompacted and showed more damage to the grooves.

Density, Viscosity, and Refractive Index Data for a Ternary System of Wine Congeners (Ethyl Butyrate + Diethyl Succinate + Isobutanol) in the Temperature Range from 288.15 to 323.15 K and at Atmospheric Pressure

Density, viscosity, and refractive index data for the ternary system ethyl butyrate + diethyl succinate + isobutanol and binary system ethyl butyrate + diethyl succinate have been measured in the temperature range 288.15–323.15 K, with temperature step of 5 K, and at atmospheric pressure. The measurements were performed on an Anton Paar DMA 5000 digital vibrating tube densimeter, Anton Paar SVM 3000 digital viscometer, and Anton Paar RXA 156 refractometer. Based on the corresponding binary data, as well as ternary data, presented in this work, excess molar volumes (VE), viscosity deviations (Δη), and refractive index deviations (ΔnD) were determined and fitted by the Redlich–Kister and Nagata–Tamura polynomial equations. The influence of mixture composition on values of excess molar volume, deviation functions, and the molecular interactions present in the mixtures was further discussed.

Influence of Mixture Composition and Type of Cementitious Materials on Enhancing the Fresh Properties and Stability of Self-Consolidating Rubberized Concrete

An experimental investigation was conducted to study the development of self-consolidating rubberized concrete (SCRC) with improved flowability, passing ability, stability, and strength for multiple structural applications. The investigation particularly aimed to maximize the percentage of used crumb rubber (CR) in SCRC while minimizing the reduction in strength and stability of the developed mixtures. The experimental test parameters included CR percentage (0–50% by volume of sand), binder content (500–550 kg/m3), coarse aggregate size (10–20 mm), air entrainment, and supplementary cementing material (SCM) (fly ash, ground granulated blast-furnace slag, and metakaolin). The performance of the developed SCRC was evaluated based on the results for compressive strength, flowability, passing ability, high-range water-reducer admixture (HRWRA) demand, coarse aggregate segregation, and CR distribution. The results indicated that mixtures with 500 kg/m3 binder content had acceptable strength, fresh properties, and stability with up to 15% CR replacement. Using 550-kg/m3 binder content improved SCRC mixture stability and allowed up to 20% CR to be used safely. Compared with the other tested SCMs, metakaolin (MK) significantly improved mixture viscosity and particle suspension/distribution, which allowed the use of up to 30% CR in SCRC mixtures. The results also showed that, despite the reduction in compressive strength in mixtures with entrained air, using air entrainment in SCRC with MK further improved the fresh properties of these mixtures and allowed up to 40% CR to be used with acceptable compressive strength (25.7 MPa) and with no sign of segregation.

Factors Affecting Fluorescence Analysis of Diagnostically Important Urinary Metabolites—Influence of Mixture Composition

The fluorescent analysis of multicomponent biological materials is very difficult. To model a proper system to characterize their quality is therefore indispensable. Influence of mixture composition was studied in a mixture of three naturally occurring diagnostically important urine metabolites: indoxyl sulfate, 5-hydroxyindole-3-acetic acid, and 3-methoxy-4-hydroxymandelic acid. Relationships between these compounds were monitored by measurement of synchronous fluorescence spectrum matrix. The fluorescence emission of 3-methoxy-4-hydroxymandelic acid when combined with indoxyl sulfate, or even with 5-hydroxyindole-3-acetic acid, was utilized for the excitation of indoxyl sulfate or 5-hydroxyindole-3-acetic acid, resulting in an increase in their fluorescence and in a decrease in 3-methoxy-4-hydroxymandelic acid fluorescence intensity.

Influence of mixture composition on the properties of SCC incorporating metakaolin

This paper studies and evaluates the properties of self-consolidating concrete (SCC) containing different percentages of metakaolin (MK) by varying the mixture components and mixture proportions. In total, 32 mixtures with varied percentages of MK and mixture compositions are investigated for the effects on compressive strength, flowability, passing ability and high-range water-reducer admixture (HRWRA) demand. The percentage of MK, coarse-to-fine aggregate (C/F) ratio, coarse aggregate size, binder content and percentage of air entrained in the mixture are varied to study the influence of these variables on the fresh properties of SCC containing MK. SCC mixtures containing silica fume and SCC containing slag are also tested for comparison. The results show that increasing the percentage of MK up to 20% in SCC increases the compressive strength, viscosity, passing ability and HRWRA demand, but decreases the flowability of the mixture. In addition, the flowability of SCC mixtures improves with larger aggregate size, higher binder content and higher percentage of entrained air. The passing ability of SCC mixtures also improves with lower C/F ratio, larger aggregate size, higher binder content and the inclusion of entrained air in the mixture. The results also indicate that increasing the binder content or increasing the percentage of the entrained air has the most significant effect on improving the fresh properties of SCC mixtures.

Influence of mixture composition on thermal properties of concrete and the performance of rigid pavement

The recent mechanistic-empirical pavement design guide (MEPDG) put more emphasis on the effects of thermal curling stresses on rigid pavement analysis and design. Mix design of concrete has significant influence on its thermal properties such as thermal conductivity, coefficient of thermal expansion, and specific heat. Aggregate type and content significantly alter the thermal properties of concrete incorporating them. The moisture state of the concrete increases its specific heat and thermal conductivity. A review of the effect of temperature of fresh concrete on early age properties is also presented. The performance of rigid pavements exposed to seasonal and daily fluctuations in temperature is discussed. Airfield concrete pavements which are subjected to jet engine exhausts experience heat cycles micro-cracking, coarsening of microstructure and loss of compressive and flexural strength. These effects are mostly the result of the dehydration and decomposition of paste matrix in concrete. Heat cycles result in concrete deterioration similar in appearance to freezing and thawing deterioration.

CARCASS QUALITY OF BROILER CHICKENS OF TWO HYBRID LINE SLAUGHTERED IN DIFFERENT AGE

The evaluation of carcass quality of broiler chickens is a very important segment in production, manufacture and marketing of poultry products, which depends of many factors. The aim of this experiment was to determine some criterions of carcass quality (carcass mass, dressing percentage and their variances) of fattening chickens in dependence on the following factors: hybrid, sex, age and mixture composition. Forty male and forty female chickens of two hybrid lines Cobb 500 and Hubbard Classic at the fifth, sixth and seventh weeks of age were selected for slaughter by the random selection method. Chickens were fed with two different mixtures which contented different level of protein and energy and different values of the E : P rate. The dressing percentage was represented by three kinds of dressings: basic or traditional dressing, “ready for roasting” and “ready for grilling”. The obtained results showed statistically significant (P < 0.05) influence of age and sex on the carcass mass. Namely, the broiler chickens slaughtered at the seventh age of week as well as the male chickens had the biggest carcass mass in all kind of dressing. The factor age had statistically significant (P < 0.05) influence on the dressing percentage in general, while the factor hybrid had a significant (P < 0.05) influence only on the dressing “ready for grilling”. Female broiler chickens in comparison with male chickens had a better dressing percentage at all kinds of dressing, but those differences were not statistically significant. Differences in carcass mass and dressing percentage under the influence of mixture composition were almost insignificant.

Influences of mixture composition on properties and freeze–thaw resistance of RCC

The paper reports a series of lab investigations carried out on roller compacted concrete (RCC) mixtures containing a wide range of cement contents (100 and 450 kg/m 3). The key objectives were to appreciate the effects of variations in the cement content and air entrainment on basic physical, mechanical properties and freeze–thaw (F–T) resistances of RCC mixtures. The Vebe consistency, moisture–density relations, water absorption, permeable voids, compressive strength, and F–T resistances of comparable mixes were evaluated. Physical and mechanical properties indicated a significant deviation from the behavior shown by conventional concrete. Air entrainment was found to be affecting the strength and F/T durability of the mixes. Further analysis shows wide range applications of RCC in various pavement applications.

Investigating the fatigue performance of grouted macadams

A conventional grouted macadam is manufactured by producing a highly porous asphalt skeleton (25–35% voids), and filling the voids with a selected highly flowable cementitious grout. Grouted macadam combines some of the best qualities of concrete and asphalt pavements, namely the flexibility and absence of joints which characterise asphalt and the high static bearing capacity and wear resistance of concrete. Moreover grouted macadam layers are impermeable and efficiently distribute the stresses in the underlying base layer. The speed of construction of grouted macadam surfacings and the short duration required prior to opening to traffic is a major advantage over conventional concrete. Current fields of applications include: airport pavements, industrial floors, harbours, bus terminals, distribution centres, and other heavily stressed areas. The aim of this investigation was to assess the fatigue behaviour of a range of grouted macadam mixtures. Indirect tensile fatigue tests and two point bending tests were conducted on laboratory manufactured specimens and on samples extracted from a trafficked pavement test facility. The experimental work provided interesting data on the influence of mixture composition on fatigue life and highlighted differences between strain and stress-controlled fatigue tests on performance of grouted macadam mixtures compared with conventional asphalts.