Background: The mechanical and physical properties of Polymethyl methacrylate (PMMA) don’tfulfill the entire ideal requirements of denture base materials. The purpose of this study was to produce new modified polymer nanocomposite (PMMA /ZrO2-TiO2) andassess itsimpact strength, transverse strength and thermal conductivity in comparison to the conventionalheat polymerized acrylic resin. Materials and Methods: Both ZrO2 and TiO2nano fillers were silanized with TMSPM (trimethoxysilyl propyl methacrylate) silane coupling agent before beingdispersed by ultrasonication with the methylmethacrylate (monomer) and mixed with the polymer by means of 2% by weight in (1:1) ratio, 60 specimens were constructed by conventional water bath processing technique and divided into 2 groups: 30 specimens for control group 0% nanofillers and 30 specimens for experimental group 2% of (1:1) ZrO2 and TiO2nano fillers then each group was subdivided into3 sub-groups according to the test to be conducted with 10 specimens for impact, transverse and thermal conductivity test. Results: The interaction of TMSPM silane and the nanofillers was confirmed by FT-IR (Fourier Transform Infra-red spectrophotometer). High significant increase in impact strength (9.838) Kj/m2 and transverse strength (101.705) N/mm2 and non-significant increase in thermal conductivity (0.286) W/m.C° of heat cured acrylic resin of the new polymer nanocomposite were observed. Conclusions: The addition of 2 wt.% of ZrO2:TiO2 by means of 1:1 ratio considerably improved the impact and transverse strength and had a positive effect on the thermal conductivity.
The present study was directed to determine the effect of silver nanoparticles (Ag NPs) on the weights of the testes and epididymides and the characteristics of sperm in male albino mice. Animals were orally dosed with 200 mg/kg of Ag NPs for 5,10,15 days and then during the day following the end of dosage period all animals were sacrificed, then the testes and epididymes (head and tail) were isolated and after their weights measured. Then we studied the percentage of vitality and sperm abnormalities and calculate the concentration of sperm in the testes and epididymides. The results of this study after comparing it with the control showed a statistical decrease (P<0.05) in the weights of testes and tunica albuginea for the three peri
... Show MoreThe Nuclear structure of 110-116Cd isotopes was studied theoretically in the framework of the interacting boson model of IBM-l and IBM-2. The properties of the lowest mixed symmetry states such as the 1+, 2+ and 3+ levels produced by the IBM-2 model in the vibrational-limit U(5) of Cd - isotopes are studied in details. This analysis shows that the character of mixed symmetry of 2+ is shared between and states in 110-114Cd – isotopes, the large shar goes to s, while in isotope, the state is declared as a mixed symmetry state without sharing. This identification is confirmed by the percentage of F-spin contribution. The electromagnetic properties of E2 and Ml operators were investigated and the results were analyzed. Various
... Show MorePolymer composite materials were prepared by mixing epoxy resin with sand particles in three different grain size (150-300 ), (300-600 ) and (600- 1200) μm . The weight of epoxy was 15%, 20%, 25% and 30% of the total weight. Compression strength and flexural strength tests were carried out for the prepared samples .The percentages of epoxy resin at 20% wt and 25% wt showed best mechanical properties for all grain sizes .These percentages were adopted to fill the void between particles sand which have two different size ranges (150-600) μm and {(150-300) & (600-1200)} μm respectively to obtain more dense material. The results showed that the strength of polymer composite at 20% resin is higher than 25% resin. The
... Show MoreIn the recent years, some of the newly constructed asphalt concrete pavements in Baghdad as well as other cities across Iraq showed premature failures with consequential negative impact on both roadway safety and economy. Frequently, load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some poorly drained sections are the main failure types found in those newly constructed road.
In this research, hydrated lime was introduced into asphalt concrete mixtures of wearing course in two methods. The first one was the addition of dry lime on dry aggregate and the second one was the addition of dry lime on saturated surface dry aggregate moisturized by 2.0 to 3.0 percent of wa
... Show MoreIn this paper, a construction microwave induced plasma jet(MIPJ) system was used to produce a non-thermal plasma jet at atmospheric pressure, at standard frequency of 2.45 GHz and microwave power of 800 W. The working gas Argon (Ar) was supplied to flow through the torch with adjustable flow rate using flow meter regulator. The influence of the MIPJ parameters such as applied voltage and argon gas flow rate on macroscopic microwave plasma parameters were studied. The macroscopic parameters results show increasing of microwave plasma jet length with increasing of applied voltage, argon gas flow rate where the plasma jet length exceed 12 cm as maximum value. While the increasing of argon gas flow rate will cause increasing into the ar
... Show MoreThe slurry infiltrated fiber concrete (SIFCON) is nowadays considered a special type of high fiber content concrete; it is high strength and high performance material. This paper investigates the effect of spread steel fiber into the slurry mortar on some properties of SIFCON. According to fiber distribution, two sets were used in this investigation. The first set consisted of randomly distributing fibers inside the slurry. The second set was by placing the fibers in an orderly manner inside the slurry. Crimped steel fibers with an aspect ratio of (60) were used. Two different volume fractions percentage of (7% and 9%) by volume of mold were used in both sets for this study. Also, a w/c ratio of (0.35) and superplasticiz
... Show MoreTo enlighten the extent of crude oil pollution effects on some anatomical characteristics of olive plant (Olea europaea ). Two years - old seedlings were chosen to grow under 5 levels of pollution (0.0, 0.5, 1.0, 2.0, and 3.0, liter/ plant). The experiment has been conducted in the experimental field of Natural History Research Center and Museum, University of Baghdad. It was designed as CRD experiment. Testing wood specimens were prepared after 2.5 years of growth. Fiber length, width, wall thickness, and wood specific gravity were measured. Results showed that olive plants could not resist the highest level ( 3 liters / plant ) of pollution .Fiber length was the most affected property by treatment. All fiber dimensions wer
... Show MoreThe effect of Wood Flour addition to the gamma alumina powder used in the preparation of gamma alumina (ɤ-Al2O3) catalyst carrier extrudates on the pore volume and BET surface area physical properties was investigated. Two parameters which are size of wood flour particles and its quantity were studied. The sizes of wood flour particles used are 150 µm, 212 µm and 500 µm and the weight percentage added to the gamma alumina powder during the preparation of the extrudates are (1%, 3%, 5% and 10%). The results showed that the addition of wood flour to the gamma alumina powder in order to get gamma alumina extrudates used as catalyst carrier is one of the successful methods to improve the pore volume
... Show MoreIn this study, the mechanical properties of an epoxy and unidirectional woven carbon with fiberglass composite were experimentally investigated. When preparing the composite samples, American Society for Testing and Materials (ASTM)standard was used. Tensile, impact and flexural test were conducted to investigate the mechanical properties of the new produced epoxy Unidirectional Woven Carbon and Epoxy Fiberglass composites. The outcome showed that the strength of the produced samples increased with the increase in the number of unidirectional woven carbon layers added. Two methods were utilized: (1) woven carbon composite with glass fiber (2) woven carbon composite). The two methods of composite were compared with each other. The resul
... Show MoreIn the present study, a powder mixture of elements Ti and Ni was mechanically alloyed in a high energy ball mill. Microstructure of the nanosized amorphous milled product in different stages of milling has been characterized by X- ray diffraction, scanning electron microscopy and differential thermal analysis. We found that time of mechanical alloying is more significant to convert all crystalline structure to the amorphous phase. Nanocrystalline phase was achieved as a result of the mechanical alloying process. The results also indicates that the phase transformation and the grain size occurs in these alloys are controlled by ball milling time