Refractories are mineral and chemical-, based, materials with excellent heat resistance, making them ideal for use in the construction of ovens, furnace walls industries. According to this our research is concerned to study the effect of addition of (4% CaO) and (5% graphite) on the silica brick properties. Different amounts of CaO and Graphite were included in the white sand (raw ingredients) of silica bricks as a binder to prepare the composition then the composition were sintered using Different sintering temperatures ranging from (1000–1400)𝛐C under static air. Density, thermal conductivity, porosity, and water absorption Compression there was power tested after sintering. XRD analysis was used to identify raw materials’ physical, chemical, and mechanical qualities, as well as their mineralogical composition. Addition of Graphite to the firebrick mixture increased the challenges of getting good densification out of firebrick specimens with enhancement of the compressive, strength, bulk density especially at low firing temperatures since it increases formation of glassy phase as compared with 4%CaO, Addition of 4% CaO to silica brick the density of firebrick decreased, and the porosity and water absorption increased. Thermal conductivity of firebrick is decreased for 5% Graphite in comparison with 4% CaO to produce refractory silica brick with high quality of heat resistance, making them ideal for use in the construction of ovens, furnace walls industries.
Tight reservoirs have attracted the interest of the oil industry in recent years according to its significant impact on the global oil product. Several challenges are present when producing from these reservoirs due to its low to extra low permeability and very narrow pore throat radius. Development strategy selection for these reservoirs such as horizontal well placement, hydraulic fracture design, well completion, and smart production program, wellbore stability all need accurate characterizations of geomechanical parameters for these reservoirs. Geomechanical properties, including uniaxial compressive strength (UCS), static Young’s modulus (Es), and Poisson’s ratio (υs), were measured experimentally using both static and dynamic met
... Show MoreThe guava plant, Psidium guajava L., serves as proof of the abundant donations of nature, providing a delicious guava fruit; this plant is rich in groups of medicinal and nutritional benefits. Guava belonging to the Myrtaceae family, many previous studies reported many phytochemical constituents in its leaves that have many pharmacological activities and medicinal properties; this study focuses on the isolation, structural elucidation and calculation concentration of flavonoids, assessment of the cytotoxic activityof hyperin from Psidium guajava leaves newly cultivated in Iraq. The isolation process involved the use of thin-layer chromatography (TLC) and preparative high-performance liquid chromatography (PHPLC) and structural eluci
... Show MoreBackground Microorganisms and fungal growth especially Candida albicans, on soft denture lining material are the most common problem which can lead to chronic mucosal inflammation. The aim of this study was to evaluate the effect of zirconium nanoparticles into acrylic-based heat cured soft denture lining material against Candida albicans, and the amount of zirconium ion release of soft liner/ZrNPs composite. Furthermore, evaluate shear bond strength after ZrNPs addition to soft liner. Materials and methods: Zirconium nanoparticles were added into acrylic-based soft denture liner in various percentages (1%, and 1.5% by weight). Two hundred and fifty specimens were arranged and isolated into four groups as per the test to be done The antifu
... Show MoreFriction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt. This process uses a nonconsumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force, etc., and tool pin profile play a major role in deciding the weld quality. In this investigation an attempt
has been made to understand the effect of tool pin profile and rotation diameter on microstructure and mechanical properties in aluminum alloy (2218-T72). Five different tool pin profiles (straight cylindrical, threaded cylindrical, triangular, square, and threaded cylindrical with flat), with three different rotation
d
The accumulation of construction and demolition waste is one of the major problems in modern construction. Hence, this research investigates the use of waste brick in concrete. Seven different concrete mixes were investigated in this study: a control concrete mix, three mixes with volumetric replacement (10, 20, and 30)% of natural aggregate with brick aggregate, and two mixes with the addition of nano brick powder at a percentage level of 5– 10% by weight of cementitious materials. And the last one was mixed with 10% nano brick and 10% coarse brick aggregate. The experimental results for the additive of nano brick powder showed an enhancement in mechanical properties (compressive,
A new 4-thiazolidinone, substitutedbenzylidene-thiazolidinone and tetrazole were synthesized from thiosemicarbazone and hydrazone. The thiosemicarbazone was prepared by the reaction of thiosemicarbazide with aldehyde derivative from L-ascorbic acid in absolute ethanol using glacial acetic acid as a catalyst. 1, 3-thiazolidin-4-ones were synthesized from the condensation of thiosemicarbazones with chloroacetic acid in presence of anhydrous sodium acetate. A 1, 3- thiazolidine-4-one was reaction with several 4-substitutedaldehydes to produce new derivatives with a double bond at the position-5 of the 4-thiazolidinone ring. While the tetrazole compounds were synthesized by 1, 3-cycloaddition reaction of sodium azide and hydrazone compounds in
... Show MoreAbstract:
The research aimed to know favoured mass media for children and
modifying their behaviour ,the child became aquires the information from
mass media that he exposure them without any guidance , where upon the
quidance proqrammes becomes real danger whereas qet out their civil
style and converting to deadly poisons,and because of little study for this
supject the two researchers opined to perform astudy to know the favoured
mass media to the children and what are the mass media that modify their
behavior according to ther parent points of view ,after propring the research
measurement and the suilable statical methods it has shown that there are
mass media affect in children behavior ,they are st
The petrophysical characteristics of five wells drilled into the Sa'di Formation in the Halfaya oil field were evaluated using IP software to determine a reservoir and explore hydrocarbon reserve zones. The lithology was evaluated using the M-N cross-plot method. The diagram showed that the Sa'di Formation was mainly composed of calcite (represented by the limestone region) is the main mineral in the Sa′di Reservoir. Using a density-neutron cross plot to identify the lithology showed that the formation mainly consists of limestone with minor shale. Gamma-ray logs were employed to calculate the shale quantity in each well. The porosity at weak hole intervals was calculated using a sonic log and neutron-density log at the reservoir
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