In this study, derivatives of polyvinyl alcohol (PVA) grafted with phthalic anhydride (PhA) and dyes were prepared to produce polymeric materials of PVA-g-PhA, PVA-g-PhA-anthocyanin, PVA-g-PhA-bromophenol blue, and PVA-g-PhAthymol blue. The materials were characterised by FTIR and 1 H NMR spectroscopies. The crystallinity of the polymers was evaluated with powder X-ray difraction, and the thermal stability by thermogravimetric analysis (TGA). The synthetic procedure for the polymeric materials entailed the formation of esters. The FTIR spectra of the polymers confrmed their formation since the ester carbonyl group stretch was observed at approximately 1691–1716 cm−1 in each material. NMR spectroscopy confrmed the addition of the dyes to the PVA-g-PhA backbone. All the powder X-ray difractograms displayed the characteristic peak for PVA at a 2θ value of approximately 20°, as well as a small peak at 42° indicative of the semicrystalline nature of the samples. These difractograms indicate a small degree of crystallinity in a mainly bulk amorphous phase. Adding dyes to PVA-g-PhA improved the thermal stability of the resulting polymers. The PVA-g-PhA-bromophenol blue material was the most thermally stable. The absorption properties of PVA-g-PhA were extended into the visible region by the attachment of the dyes. The photostability of the polymers was investigated by irradiating them with 254 nm light. The absorbance of the parent material, PVA-g-PhA, and the anthocyanin derivative increased with irradiation time until it reached a photostationary state. This increase in absorbance is attributed to the formation of more conjugated structures or light-absorbing photoproducts. On the other hand, the PVA-g-PhA-bromophenol blue and PVA-g-PhA-thymol blue materials photodegraded with increasing irradiation time. This research has shown that grafting dyes onto PVA can improve thermal stability and extend light absorption into the visible region. In particular, the addition of anthocyanin dye improved the photostability of the resulting material.
Two series of 1,3,4-oxadiazole derivatives at the sixth position of the 2,4-di-
Objective: to evaluate body image and depression symptoms of children with precocious puberty, and find out association between children`s sociodemographic characteristics and their body image and depression signs. Methodology: A cross sectional study, sample of (80) child from both gender, > 7 years were included due to their ability to express their own feeling, diagnosed with precocious puberty, attending out-patient endocrine clinics at pediatric hospitals in Baghdad city. Data collected, during the period from May to November 2018. Consent form has taken from children and their guardians to participate in study. Child body image scale (CBIS) was used to evaluate children body satisfaction (1) and Mood and feeling questionnaire (M
... Show MoreThe cheif aim of the present investigation is to develop Leslie Gower type three species food chain model with prey refuge. The intra-specific competition among the predators is considered in the proposed model. Besides the logistic growth rate for the prey species, Sokol Howell functional response for predation is chosen for our model formulation. The behaviour of the model system thoroughly analyses near the biologically significant equilibria. The linear stability analysis of the equilibria is carried out in order to examine the response of the system. The present model system experiences Hopf bifurcation depending on the choice of suitable model parameters. Extensive numerical simulation reveals the validity of the proposed model.
Plasma alkaline phosphatase isozyme in Iraqi fowl was studied by acrylamide gel electrophoresis. Two phenotypes fast and slow, were observed. These two phenotypes have been shown to be controlled by one single autosomal locus with two allel AKPF and AKPS. The gene frequency of AKPS is dominant over the AKPF. The result indicated that gene frequency of AKPF in leghorn and new hamshire was more frequent than in local Iraqi birds. Birds of fast isozyme type had higher 90 – day's egg production and egg weights as compared to those with slow isozyme. It is concluded that the fast isozyme can be used as gene marker for spotting out pullets with high body weight sexual maturity, high egg production and high egg weight.
In this study, we made a comparison between LASSO & SCAD methods, which are two special methods for dealing with models in partial quantile regression. (Nadaraya & Watson Kernel) was used to estimate the non-parametric part ;in addition, the rule of thumb method was used to estimate the smoothing bandwidth (h). Penalty methods proved to be efficient in estimating the regression coefficients, but the SCAD method according to the mean squared error criterion (MSE) was the best after estimating the missing data using the mean imputation method
This research aims to know the essence of the correlative relationship between tactical thinking and solving mathematical problems. The researchers followed the descriptive research method to analyze relations, as all students from the mathematics department in the morning study were part of the research group. The research sample of (100) male and female students has been chosen based on the arbitrators' views. The tools for studying the sample of research composed of (12) items of the multiple-choice test in its final form to measure tactical thinking and require establish-ing a test of (6) test-type paragraphs to solve mathematical problems. The findings showed that sample students' tactical thinking and their capacity to overcome mathem
... Show MoreThe direct electron transfer behavior of hemoglobin that is immobilized onto screen-printed carbon electrode (SPCE) modified with silver nanoparticles (AgNPs) and chitosan (CS) was studied in this work. Cyclic voltametry and spectrophotometry were used to characterize the hemoglobin (Hb) bioconjunction with AgNPs and CS. Results of the modified electrode showed quasi-reversible redox peaks with a formal potential of (-0.245 V) versus Ag/AgCl in 0.1 M phosphate buffer solution (PBS), pH7, at a scan rate of 0.1 Vs-1. The charge transfer coefficient (α) was 0.48 and the apparent electron transfer rate constant (Ks) was 0.47 s-1. The electrode was used as a hydrogen peroxide biosensor with a linear response over 3 to 240 µM and a detection li
... Show MoreIt is recognized that organisms live and interact in groups, exposing them to various elements like disease, fear, hunting cooperation, and others. As a result, in this paper, we adopted the construction of a mathematical model that describes the interaction of the prey with the predator when there is an infectious disease, as well as the predator community's characteristic of cooperation in hunting, which generates great fear in the prey community. Furthermore, the presence of an incubation period for the disease provides a delay in disease transmission from diseased predators to healthy predators. This research aims to examine the proposed mathematical model's solution behavior to better understand these elements' impact on an eco-epidemi
... Show More