scholarly journals Effect of Sand Wetting on Physically Hardened Moulding Sands Containing a Selected Inorganic Binder. Part 1

2016 ◽  
Vol 16 (1) ◽  
pp. 73-78
Author(s):  
M. Stachowicz ◽  
K. Granat ◽  
Ł. Pałyga
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Water Glass ◽  
Mechanical Parameters ◽  
Significant Positive Effect ◽  
Technological Parameters ◽  
Physical Methods ◽  
High Silica ◽  
Positive Effect

Abstract In the paper, an attempt was made to evaluate the effect of preliminary wetting of high-silica base during preparation of moulding sands containing a selected grade of sodium water-glass, designed for hardening by traditional drying or by electromagnetic microwaves at 2.45 GHz. In the research, some water was dosed during stirring the sandmix before adding 1.5 wt% of the binder that was unmodified sodium water-glass grade 137, characterised by high molar module within 3.2 to 3.4. Scope of the examinations included determining the effect of wetting the base on mechanical parameters like compression, bending and tensile strength, as well as on technological parameters like permeability, abrasion resistance and apparent density. The research revealed a significant positive effect of adding water to wet surfaces of high-silica base grains on mechanical properties and quality of moulding sands hardened by physical methods, in particular by microwave heating.

Compositions Based on Nanosized Powders Carbides of Tungsten and Titanium, Obtained by the Method Self-Propagating High Temperature Synthesis for the Modification of Gray Cast Iron and Steel 110g13L

2019 ◽  
Vol 802 ◽  
pp. 43-56
Author(s):  
Mikhail Georgievich Leontiev
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Tensile Strength ◽  
Cast Iron ◽  
Crystallization Process ◽  
Technological Parameters ◽  
Nanosized Powders ◽  
Iron And Steel ◽  
Average Grain Size

Iron-based alloys (steel and cast iron) are currently the main structural materials that provide a high level of mechanical and technological properties along with a relatively low cost. Increasing the performance characteristics (tensile strength, hardness, wear resistance, corrosion resistance and, ultimately, service life) of cast irons and steels is an urgent task. The quality of castings made of cast iron and steel depends on many technological parameters that affect the processes of crystallization of the melt (casting temperature, molding mixture, chemical composition, volume of casting, overheating of the metal during smelting, etc.). It is possible to improve the quality of castings without changing the technology of smelting and pouring metal into molds, if you learn how to manage the crystallization process. The laboratories have grown defect – free iron crystals with a tensile strength of more than 1000 kg/m2 (strength of carbon steel-40 kg/m2). Attempts to improve the mechanical properties by creating a single crystal are not justified, so you have to go the opposite way-to influence the crystallization process to get a lot of small crystals (grains), which also allows you to achieve high mechanical properties. The dependence of the strength characteristics on the grain size is well described by the law of Hall-Petch, according to which when the average grain size is reduced by 3...5 times there is an increase in the hardness of the material, with a further decrease in the average grain size by more than 10 times – an increase in plasticity. Influence on the processes of crystallization of iron and steel melts (change the size of metal grains, change the shape, size and distribution of graphite inclusions) can be the introduction of small additives substances (modifiers), not chemically interacting with the matrix. The use of modifiers to increase the rate of crystallization, reduce the structural heterogeneity of castings has good prospects. In addition, unlike doping, modification does not require a large number of expensive additives and, accordingly, slightly increases the final cost of production.

scholarly journals The Influence of Different Plasma Cell Discharges on the Performance Quality of Surgical Gown Samples

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4329
Author(s):  
Atif H. Asghar ◽  
Ahmed Rida Galaly
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Exposure Time ◽  
Electrical Characteristics ◽  
Cathode Fall ◽  
Treatment Efficiency ◽  
Performance Quality ◽  
Surgical Gown ◽  
The One

An experimental study was performed on a low-density plasma discharge using two different configurations of the plasma cell cathode, namely, the one mesh system electrodes (OMSE) and the one mesh and three system electrodes (OMTSE), to determine the electrical characteristics of the plasma such as current–voltage characteristics, breakdown voltage (VB), Paschen curves, current density (J), cathode fall thickness (dc), and electron density of the treated sample. The influence of the electrical characteristics of the plasma fluid in the cathode fall region for different cathode configuration cells (OMSE and OMTSE) on the performance quality of a surgical gown was studied to determine surface modification, treatment efficiency, exposure time, wettability property, and mechanical properties. Over a very short exposure time, the treatment efficiency for the surgical gown surface of plasma over the mesh cathode at a distance equivalent to the cathode fall distance dc values of the OMTSE and for OMSE reached a maximum. The wettability property decreased from 90 to 40% for OMTSE over a 180 s exposure time and decreased from 90 to 10% for OMSE over a 160 s exposure time. The mechanisms of each stage of surgical gown treatment by plasma are described. In this study, the mechanical properties of the untreated and treated surgical gown samples such as the tensile strength and elongation percentage, ultimate tensile strength, yield strength, strain hardening, resilience, toughness, and fracture (breaking) point were studied. Plasma had a more positive effect on the mechanical properties of the OMSE reactor than those of the OMTSE reactor.

scholarly journals Numerical Studies of the Effects of Water Capsules on Self-Healing Efficiency and Mechanical Properties in Cementitious Materials

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Haoliang Huang ◽  
Guang Ye
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Cementitious Materials ◽  
Self Healing ◽  
Negative Effects ◽  
Numerical Studies ◽  
Healing Efficiency ◽  
The Impact ◽  
Positive Effect

In this research, self-healing due to further hydration of unhydrated cement particles is taken as an example for investigating the effects of capsules on the self-healing efficiency and mechanical properties of cementitious materials. The efficiency of supply of water by using capsules as a function of capsule dosages and sizes was determined numerically. By knowing the amount of water supplied via capsules, the efficiency of self-healing due to further hydration of unhydrated cement was quantified. In addition, the impact of capsules on mechanical properties was investigated numerically. The amount of released water increases with the dosage of capsules at different slops as the size of capsules varies. Concerning the best efficiency of self-healing, the optimizing size of capsules is 6.5 mm for capsule dosages of 3%, 5%, and 7%, respectively. Both elastic modulus and tensile strength of cementitious materials decrease with the increase of capsule. The decreasing tendency of tensile strength is larger than that of elastic modulus. However, it was found that the increase of positive effect (the capacity of inducing self-healing) of capsules is larger than that of negative effects (decreasing mechanical properties) when the dosage of capsules increases.

The Effect of Yarn Linear Density on Mechanical Properties of Plain Woven Kenaf Reinforced Unsaturated Polyester Composite

2013 ◽  
Vol 465-466 ◽  
pp. 962-966 ◽  
Author(s):  
Mohd Pahmi bin Saiman ◽  
Mohd Saidin Bin Wahab ◽  
Mat Uzir Wahit
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Linear Density ◽  
Unsaturated Polyester ◽  
Composite Panel ◽  
Composite Yarn ◽  
Polyester Composite ◽  
The Impact ◽  
Woven Kenaf

To produce a good quality of dry fabric for reinforced material in a natural-based polymer composite, yarn linear density should be in consideration. A woven kenaf dry fabric with three different linear densities of 276tex, 413.4tex and 759tex were produced. The fabrics with different linear densities were been optimize with the assistance of WiseTex software. The optimized dry fabrics were infused with unsaturated polyester to produce composite panel using vacuum infusion process. The composites properties were tested on the tensile strength, flexural strength and the impact strength. The result shows that the mechanical properties of the composite increased when the yarn linear densities increased.

scholarly journals The Effect of Borax Solution as Preservative to the Mechanical Properties of Bamboo

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
M.A.P Handana ◽  
◽  
Besman Surbakti ◽  
Rahmi Karolina ◽  
◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Bending Strength ◽  
Environmentally Friendly ◽  
Preservative Solution ◽  
Borax Solution ◽  
Preservative Solutions

The use of borax solution as a preservative in wood and bamboo materials is well known in the community. A borax solution is an environmentally friendly liquid that can dissolve in water, so it is suitable to be used as a preservative within cold or hot soaking techniques. The ability of borax to resist insects and fungus attacks on bamboo has been proven, but the effect of the solution on the strength of bamboo must also be investigated. This study conducts to investigate the effects of borax and its additives as preservative solutions to the mechanical properties of bamboos. The bamboos preservations were conducted by cold conditions of immersion, while the mechanical properties were performed to understand the effects of preservatives. The result of this study indicated that 30% to 50% borax in the preservative solution is sufficient to provide significant increase in strength for compressive strength, tensile strength, and bending strength of bamboo specimen. From this study, the use of borax solution in preserving the bamboos materials improved the quality of bamboos based on its mechanical properties.

scholarly journals ANALYSIS OF SYSTEM QUALITY, INFORMATION QUALITY AND PERCEIVED USEFULNESS TO USER SATISFACTION

2019 ◽  
pp. 62
Author(s):  
Tiana Tiana ◽  
Bambang Sugiharto ◽  
Indah Umiyati
Keyword(s):  
User Satisfaction ◽  
Structural Equation ◽  
Information Quality ◽  
Partial Least Square ◽  
Perceived Usefulness ◽  
Equation Modeling ◽  
Significant Positive Effect ◽  
Quality Of Information ◽  
Positive Effect

This study aims to test and analyze the quality of the system against perceived usefulness, the quality of information against perceived usefulness, the quality of the system to user satisfaction, Information Quality to user satisfaction and perceived usefulness to user satisfaction. The population in this research is employees teller and customer service department of Bank BJB in subang city. Sampling technique is nonprobability sampling by using purposive sampling method. The type of data used is primary data with questionnaire data collection method. Hypothesis testing used is Structural Equation Modeling (SEM) approach with variance Structural equation test or better known as Partial Least Square (PLS). The result of the research shows that Quality System has a significant positive effect on Perceived Usefulness, Quality of Information has a significant positive effect on Perceived Usefulness, Quality of System has a significant positive effect on user satisfaction, Information Quality has positive significant effect on user satisfaction, and Perceived Usefulness has no effect to User Satisfaction

scholarly journals Intensifications of the wooling mechanism with increasing electric conductivity of fibers

Academia Open ◽  
2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Khasanov Doston
Keyword(s):  
Mechanical Properties ◽  
Electric Conductivity ◽  
Quaternary Salt ◽  
Water Soluble ◽  
Technological Parameters ◽  
Protein Fiber ◽  
Effect Of The Composition

The wide possibilities of modifying manufactured industrial fibers aimed at improving their physico-mechanical properties, structural and technological parameters. In connection with the above, it was of interest to study the effect of a number of water-soluble compositions based on a poly-quaternary salt of dimethyl-allyl-β - methacryloyloxyethylammonium bromide in combination with glycerin on the structural and physico-mechanical properties of protein fiber, and also to study the effect of the composition on wool spinning and the quality of wool yarn .

scholarly journals PENGARUH MASA KERJA, PELATIHAN, DAN NILAI KETETAPAN PAJAK TERHADAP KUALITAS KEPUTUSAN KEBERATAN

2020 ◽  
Vol 1 (2) ◽  
pp. 73-80
Author(s):  
Amardianto Arham ◽  
Budhi Mulia Cipta ◽  
Ragil Novitasari
Keyword(s):  
Quantitative Method ◽  
Significant Positive Effect ◽  
Purposive Sampling ◽  
Significant Negative Effect ◽  
Tax Assessment ◽  
Negative Effect ◽  
Positive Effect

The purpose of this study is to analyze the effect of tenure, training, and the value of tax assessments on the quality of objection decisions. This study uses a quantitative method with purposive sampling. The results of this study indicate that the tenure does not affect the quality of the objection decision, training has a significant positive effect on the quality of the objection decisions, and the value of the tax assessment has a significant negative effect on the quality of the objection decision.  Tujuan dari penelitian ini adalah untuk menganalisis pengaruh masa kerja, pelatihan, dan nilai ketetapan pajak terhadap kualitas keputusan keberatan. Penelitian ini menggunakan metode kuantitatif dengan purposive sampling. Hasil penelitian ini menunjukkan bahwa masa kerja tidak berpengaruh terhadap kualitas keputusan keberatan, pelatihan berpengaruh positif signifikan terhadap kualitas keputusan keberatan, dan nilai ketetapan pajak berpengaruh negatif signifikan terhadap kualitas keputusan keberatan.

scholarly journals The Impact of Slicing Softwares on the Mechanical Properties of 3D Printed Parts

2020 ◽  
Vol 9 (2) ◽  
pp. 487-494
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
3D Printer ◽  
Stl File ◽  
3D Printed ◽  
Intersection Curves ◽  
The Impact

“Slicing tool” or “Slicing Software” computes the intersection curves of models and slicing planes. They improve the quality of the model being printed when given in the form of STL file. Upon analyzing a specimen that has been printed using two different slicing tools, there was a drastic variation on account of the mechanical properties of the specimen. The ultimate tensile strength and the surface roughness of the material vary from one tool to another. This paper reports an investigation and analysis of the variation in the ultimate tensile strength and the surface roughness of the specimen, given that the 3D printer and the model being printed is the same, with a variation of usage of slicing software. This analysis includes ReplicatorG, Flashprint as the two different slicing tools that are used for slicing of the model. The variation in the ultimate tensile strength and the surface roughness are measured and represented statistically through graphs. An appropriate decisive conclusion was drawn on the basis of the observations and analysis of the experiment on relevance to the behavior and mechanical properties of the specimen.

scholarly journals The Influence of Parking Careers and Parking Facilities on User Satisfaction of Car Parking on Ngurah Rai Street Gianyar City

2021 ◽  
Vol 21 (3) ◽  
pp. 212-217
Author(s):  
Ida Bagus Wirahaji ◽  
◽  
I Ketut Sutapa ◽  
Keyword(s):  
User Satisfaction ◽  
Survey Methods ◽  
Significant Positive Effect ◽  
User Perception ◽  
Traditional Markets ◽  
Car Park ◽  
Value Determination ◽  
Parking Facilities ◽  
Positive Effect

Driver satisfaction in making a trip is influenced by the quality of parking services. The purpose of this study was to analyze the effect of parking attendants and parking facilities on the satisfaction of car park users on Jalan Ngurah Rai, in Gianyar City, which is currently working on revitalizing traditional markets with modern concepts. Research using survey methods, distributing questionnaires to obtain 100 sheets of parking service user perception data. The results of the analysis show that the regression equation obtained is Y = 2.354 + 0.281 X1 + 0.672 X2. The parking attendant and parking facilities variables both partially and simultaneously have a significant positive effect on the user satisfaction variable. Value of Sig. variable parking attendant and parking facilities respectively 0.000 < 0.05. The value of tcount for parking attendants and parking facilities are 9,500 and 20.921, respectively > ttable = 1.9872. Fcount = 312.296 > 0.025324. The ability of the parking attendant and parking facilities variable in influencing the user satisfaction variable is quite large, as indicated by the coefficient value. determination (R2) of 86.3%.

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