Background: Alginate impression material is the irreversible hydrocolloid material that is widely used in dentistry. The contact time between alginate and gypsum cast could have a detrimental effect on the properties of the gypsum cast. The objective of this study is to evaluate the impact of various contact time intervals of Alginate impressions & type III dental stone on surface properties of stone cast. Materials and Methods: Time intervals tested were 1hour, 6 hours and 9 hours. Surface properties of stone cast evaluated were surface detail reproduction, hardness and roughness. Surface detail reproduction was determined using cylindrical brass test block in accordance with ISO 1563. Surface roughness was measured by profilometer and hardness was measured by Durometer (Shore D). Results: The detail reproduction showed significant difference (P<0.05), at 6 hr., and 9 hr. showed better results. While surface roughness significantly decreased (p<0.01) with prolonged contact time. However, surface hardness increased significantly (p<0.01) with increased contact time. Conclusions: Surface detail reproduction increased with increasing the contact time and this was noticed at (6, 9 hours). However, 1hour time interval showed decreased surface detailed reproduction. Roughness decreased when the contact time was increased between type III dental stone and alginate impression whereas, hardness was improved significantly with increasing contact time.
The doping process with materials related to carbon has become a newly emerged approach for achieving an improvement in different physical properties for the obtained doped films. Thin films of CuPc: C60 with doping ratio of (100:1) were spin-coated onto pre-cleaned glass substrates at room temperature. The prepared films were annealed at different temperatures of (373, 423 and 473) K. The structural studies, using a specific diffractometry of annealed and as deposited samples showed a polymorphism structure and dominated by CuPc with preferential orientation of the plane (100) of (2θ = 7) except at temperature of 423K which indicated a small peak around (2θ = 3
The current investigation included study of leaf surface epidermis beside indumentum for the species Galium aparine L., G. ceratopodum Boiss, G. setaceum Lam., G. spurium L., and G. tricornatum Dandy, the study showed that paracytic type of stomatal complex is the only type occur in leaf. The indumentum compose of eglandular hairs vary in their apices, length and occurrence of different part of plant body
The optical properties for the components CuIn(SexTe1-x)2 thin films with both values of selenium content (x) [0.4 and 0.6] are studied. The films have been prepared by the vacuum thermal evaporation method with thickness of (250±5nm) on glass substrates. From the transmittance and absorbance spectra within the range of wavelength (400-900)nm, we determined the forbidden optical energy gap (Egopt) and the constant (B). From the studyingthe relation between absorption coefficient (α) photon energy, we determined the tails width inside the energy gap.
The results showed that the optical transition is direct; we also found that the optical energy gap increases with annealing temperature and selenium content (x). However, the width of l
Abstract : Silicone elastomer is widely used as the material of choice for fabricating maxillofacial prosthesis. However, silicone properties are far from ideal; low tear strength, low tensile strength and insufficient elasticity are the most undesirable properties. The purpose of this study was to evaluate the effect of addition of nano SiO2filler on tear strength, tensile strength, elongation at break, hardness and color of Cosmesil M-511 HTV maxillofacial silicone elastomer. Nano SiO2was added to the silicone base in concentrations of 4%, 5% and 6% by weight. Silicone with 0% nano filler served as a control. Tear test was done according to ISO 34-1. Tensile and elongation test was done according to ISO 37. Shore A hardness test was done
... Show MoreThis study was conducted in the autumn season of 2024-2025 in the fields of the College of Agricultural Engineering Sciences – University of Baghdad, to investigate the effect of organic fertilizers prepared using sesame and soybean husks, and foliar application with milk thistle extract (Silybum marianum), on the qualitative properties of Italian kale plants. The experiment was conducted as factorial experiment (6×3) in a randomized complete block design (R.C.B.D.) with split-plot arrangement and three replicates. Factors were included: the first factor (six fertilization treatments : chemical fertilization at recommended rates , two levels each of organic sesame husks (2 and 4 kg m⁻²) and soybean husks (2 and 4 kg m⁻²
... Show MoreSome of the issues that have become common in our society recently after the Americans entered our country and were rubbed by some security agencies: obtaining some information from children, and the serious consequences that may lead to the lives of innocent people, became common interrogation of some security agencies and rely on their words.
There are significant cases where their testimony needs to be heard, such as their presence in some places where incidents are not witnessed by others, such as schools or being witnesses to certain crimes.
I saw the study of this case in the light of Sharia and law
Background: The displacement of artificial teeth during complete denture construction presents major processing errors in the occlusal vertical dimension which were verified at the previous trial denture stage. The aim of this study was to assess the effect of delay in processing after final flask closure and tension application on the vertical acrylic and porcelain teeth displacement of complete dentures constructed from heat cured acrylic and the results were compared with the conventional processing method. Materials and methods: forty samples of identical maxillary complete dentures were constructed from heat polymerized acrylic resin. These samples were subdivided into the following experimental subgroups in which each subgroup contai
... Show MoreAlloys were performed from In2O3 doped SnO2 with different doping ratio by quenching from the melt technique. Pulsed Laser Deposition PLD was used to deposit thin films of different doping ratio In2O3 : SnO2 ( 0, 1, 3, 5, 7 and 9 % wt.) on glass substrate at ambient temperature under vacuum of 10 -3 bar thickness of ~100nm. The structural type ,grain size and morphology of the prepared alloys compounds and thin films were examined using X-ray diffraction and atomic force microscopy . The results showed that all alloys have polycrystalline structures and the peaks belonged to the preferred plane for crystal growth were identical with the ITO (Indium – Tin –Oxide) standard cards also another peaks were ob
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