In this work, varying compositions of SiO2 micro filler were added
with the Polyvinyl Chloride (PVC) and samples have been prepared
using film casting technique. The results have been analyzed and
compared for PVC samples with (1 wt%, 3 wt%, 5 wt% and 10 wt%)
SiO2 micro filler. Mechanical characteristics such as tensile strength,
elongation at break and Young`s modulus were measured for all the
samples, where the tensile strength was increased from 8.39 Mpa for
purified PVC to 16 Mpa for 3% SiO2/PVC composite. Also, thermal
conductivity measurement values illustrated that composite materials
have a good thermal insulation at 10 wt. %, thermal conductivity was
decreased from 0.1684 W/m. K for PVC to 0.1310W/m. K at 10%
SiO2/PVC composite. Absorptivity test was also carried out for these
samples, the results of this study proved that PVC and SiO2-PVC
composites have low diffusion coefficients ranging from (10-13- 10-10
m2/s). Similarly, the dielectric properties like dielectric constant, loss
factor, resistance, and volume resistivity were performed; the
dielectric constant was increased from 2.1039 for PVC to 3.658 for
3% SiO2/PVC composites, while the dielectric loss factor was
decreased from 0.0144 for PVC to 0.0137 for 5%SiO2/PVC
composite. The values of resistance were increased from
17259.99(Ω) for purified PVC to 29185.75(Ω) for 10% SiO2/PVC
composites. Volume resistivity was increased from 0.3794 x109 (Ω.
cm) for PVC to 0.5179x109 (Ω. cm) for 10% SiO2/PVC composites.
FTIR spectroscopy was employed for all PVC-composite samples
and its results were investigated, there are systematic increases in
absorbance intensity spectra with SiO2 ratios attributed to good
distribution of inorganic fillers (Symmetric increases). The
microstructure and morphology of the prepared samples were
investigated by using optical microscope. It can be observed that, the
samples with (3% SiO2/PVC) are glossy and smooth without
agglomeration of (SiO2) particles in (PVC) matrix. The results
demonstrate that PVC-composite films prepared in this study show
promising potential to achieve good materials for plastic packaging
applications.
The species of Opilio kakunini Snegovaya, Cokendolpher & Mozaffarian, 2018 was recorded for the first time in Iraq; as well as to four species belonging to this order which were recorded previously. In this paper, we added a new species to the checklist of Iraqi opilionid fauna with a description of the most important characteristics, along with genitalia, for both males and females are presented with digital photographs. Specimens of males and females were collected from Al- Rifai district northern of Dhi-Qar Province, southern of Iraq.
To promote sustainable steel-concrete composite structures, it is essential to develop special shear connectors that facilitate accelerated construction and deconstruction. A lockbolt demountable shear connector (LBDSC) was recently proposed. While the LBDSC has been evaluated using horizontal and vertical (standard) push-out tests, it is essential to further assess the disassembly mechanism and the positive flexural performance of prefabricated demountable composite beams (PDCBs) under both serviceability and ultimate limit states. Two full-scale test specimens of PDCBs with LBDSC were designed with partial shear connections and assessed using a three or four-point load beam setup under both cyclic and static monotonic loading conditions.
... Show MoreCongenital anomalies commonly occur in humans, possibly visible. If these anomalies appear in visible parts in human body such as face, hands and feet. They may only appear after utilizing a number of special tests in order to show by means of the anomalies that occur in the internal organs of the body such as heart, stomach and kidneys.
Research data have comprised accessible information in the anomalies birth statistics form situated of Health and Life Statistics section at the Ministry of Health and environment, where the number of anomalies births involved in the study (2603 anomalies birth) in Iraq, except Kurdistan region, at 2015. A two way-response logistic regression analysis h
... Show MoreThe study of entry and reentry dynamics for space vehicles is very important, particularly for manned vehicles and vehicles which is carry important devices and which can be used again. There are three types for entry dynamic, ballistics entry, glide entry and skip entry. The skip entry is used in this work for describing entry dynamics and determining trajectory. The inertia coordinate system is used to derive equations of motion and determines initial condition for skip entry. The velocity and drag force for entry vehicle, where generate it during entry into earth’s atmosphere are calculated in this work. Also the deceleration during descending and determining entry angles, velocities ratio and altitude ratio have been studied. The c
... Show MoreBackground: overweight and obesity are the fifth leadingrisk for global deaths. At least 2.8 million adults die eachyear as a result of being overweight or obese. Numerousstudies show that weight loss, even if only 5-10%,significantly improves dyslipidemia, hypertension, diabetesmellitus, risk for osteoarthritis and its symptoms and risk forselected cancers.Objectives: is to evaluate the effect of diet and exerciseprogram on anthropometric and biochemical status of adultobese patients.Methods: descriptive study. 124 adult obese patientsattending Al Kindy obesity research and therapy unit duringDecember 2012 were included. Measurement of Wt, heightHt and WC performed and BMI was calculated. Laboratorytest analysis, on the fasting state, w
... Show MoreObjective: This study was conducted to identify the association of HLA-DRB1/DQB1 genes with the susceptibility or resistance to type 1 diabetes mellitus (T1D) among patients between the ages of five and eighteen.
Subjects and Methods: The study included 200 Sudanese participants, ages ranging from 5 to 18. One hundred participants were healthy non-diabetic as the control group and 100 with T1D as the case group. The investigation was carried out in Khartoum state. The selection of patients with T1D was from diabetic centers and hospitals. The allele-specific-refractory mutation system-polymerase chain reaction (ARMS-PCR) techniq
... Show MoreSynthesis and study liquid crystalline properties of new compounds with terminal groups of amides ([III]a-c,[IV]a-c and [VI]n), alkoxy series[V]n or ester with azo linkage ([IX]a-c and[X]a-c) containing thaizole ring. These series were synthesized by many steps starting from 4- hydroxyacetophenone or 4-aminoacetophenone. The synthesized compounds were characterized using melting points, FTIR, C.H.N.S analysis and for some of them 1H NMR spectroscopy. The liquid crystalline properties were studied by hot stage polarizing microscopy and differential scanning calorimetry DSC. All compounds of series [III]a-c,[IV]a-c and compounds [V]n showed enantiotropic liquid crystal. While the series [VI]n showed nematic mesomorphism except [VI]8 did not s
... Show MoreHellenistic architecture represents an important example of the reflection of ancient Greek architecture in the art of oriental architecture in the countries of the ancient world, including those states spread across North Africa that were under the authority of the Ptolemies and who were able to transmit those artistic values and traditions of Greek architecture to those regions. The current research deals with a detailed study of those important transformations of civil and religious architecture, as well as the most important features of that architecture through the constituents of location and geographical location.