The primary purpose of the present research was to study the effect of polyvinyl chloride (PVC) powder content on ultrasonic wave velocity in PVC/Epoxy composites. The second part is concerned with the relations of dynamic elastic moduli with the ultrasonic wave velocities, to determine how ultrasonic waves can affect them.
Experimental data have been obtained using the sonic viewer (model -5217 A) device to generate two types of waves, longitudinal waves of frequency 63 kHz and transverse waves of frequency 33 kHz and to measure the transit time required for those waves to travel through individual sample.
The experimental results have shown that the propagation of the ultrasonic velocity increases directly with PVC content in the tested specimens, due to the changes in the dynamical properties that were investigated from the calculated values of the elastic moduli of the composites
Record, verify, and showcase your peer review contributions in a format you can include in job and funding applications (without breaking reviewer anonymity).
Audio classification is the process to classify different audio types according to contents. It is implemented in a large variety of real world problems, all classification applications allowed the target subjects to be viewed as a specific type of audio and hence, there is a variety in the audio types and every type has to be treatedcarefully according to its significant properties.Feature extraction is an important process for audio classification. This workintroduces several sets of features according to the type, two types of audio (datasets) were studied. Two different features sets are proposed: (i) firstorder gradient feature vector, and (ii) Local roughness feature vector, the experimentsshowed that the results are competitive to
... Show MoreThe poster is one of the means which can be communicate with others through it, to transfer ideas that the designer want to focus on, for its importance to accomplish the poster. It’s a visual mean contact aim to submit an idea to the audience to get a clear idea, and that would be through the shapes and subject to submit the idea. Depend on that our goal in this study is to find out, what follows:1-Finding the relationship between the shape and the idea.And the study comes up with several results, like:1-The drawings that contain themes connected with what the designer want to achieve, through the clearness of idea and to make those elements clear by putting more elements to surround the main shape.2-To assure that the strong connecti
... Show More
Aim To develop a low-density polyethylene–hydroxyapatite (HA-PE) composite with properties tailored to function as a potential root canal filling material. Methodology Hydroxyapatite and polyethylene mixed with strontium oxide as a radiopacifier were extruded from a single screw extruder fitted with an appropriate die to form fibres. The composition of the composite was optimized with clinical handling and placement in the canal being the prime consideration. The fibres were characterized using infrared spectroscopy (FTIR), and their thermal properties determined using differential scanning calorimetry (DSC). The tensile strength and elastic modulus of the composite fibres and gutta-percha were compared, dry and after 1 month storage in
... Show More
(5)
The D.C electrical and thermoelectrically properties of randomly mixed isolator – electrolyte system as (Al/ PVC – LiF/Al) junction consisting of polyvinyl chloride (PVC)resin reinforced with Lithium Fluoride (LiF) powder were studied. A comparison is made the properties of (PVC) material with varying percentage of (LiF) powder (0%, 30%, 50%, 80%)to find out the effect of reinforcement of isolator material. The composites dissolving in 10ml form tettraHaedroflourn (THF) and Solution were the castled in Petri dish and Laved it dry in the air, The out coming Sample were disc - Like shape of a diameter of about 3cm and thickness reneged between (0.01- 0.018) cm . The composites dissolving in 10ml form tettraHaedroflourn (THF) a
... Show More
Three types of metal carboxylates (Ho,Tb and Dy) stearates were LLSed as thennal stabi lizers for PVC. Infrared spectra (1500-1900
|
cm.1
were studied for PVC films stabilized with these metal
carboxylatcs. Two types of oxygen were round -containing products that were formed during the thermal degradation .On the other hand , the presence &nb
... Show MoreThe aim of this study is to investigate the existence of some heavy metals (lead, cadmium, chromium) in colored plastic table dishes and study the migration of these metals to the food meals and the affecting factors in migration , such as storage period and food temperature. Six kinds of colored plastic table dishes were collected from Baghdad markets. The heavy metals in table dishes and in the prepared food meals put in them were estimated using atomic absorption spectrophotometer (Shimadzu A5000). The results indicated the existence of lead in all samples (1.61_1.00 mg/ kg) and chromium in three samples (0.85_0.97 mg/ kg) while other samples are free of chromium, and cadmium. Investigating the migration of these metals to food at dif
... Show MoreAn experiment was conducted in the green garden of Department of Biology/ in College of Education for Pure Sciences Ibn-Al-Haitham/ Baghdad University for the grouth season (2012-2013) to study the effect of three concentrations of gibberellic acid (0, 50, 100) ppm and three concentrations of proline (0, 25, 50) ppm on micronutrients content (Iron (Fe), Zinc (Zn), Manganese (Mn) and Copper (Cu) ppm) in addition to total chlorophyll content (µg. cm-2) for the green part of peas plant (Pisum sativum), pots of (8 kg) soil were used, the experiment was conducted according to complete randomized design (CRD) and three replicates, whereby the experiment included (27) pots, the significant variations were compared between means using least s
... Show More