PVA, Starch/PVA, and Starch/PVA/sugar samples of different
concentrations (10, 20, 30 and 40 % wt/wt) were prepared by casting
method. DSC analysis was carried; the results showed only one glass
transition temperature (Tg) for the samples involved, which suggest
that starch/PVA and starch/PVA/sugar blends are miscible. The
miscibility is attributed to the hydrogen bonds between PVA and
starch. This is in a good agreement with (FTIR) results. Tg and Tm
decrease with starch and sugar content compared with that for
(PVA). Systematic decrease in ultimate strength, due to starch and
sugar ratio increase, is attributed to (PVA), which has more hydroxyl
groups that made its ultimate strength higher than that for
starch/PVA, and starch/PVA/sugar blends. It is observed from water
uptake tests that the solubility time decreases with starch ratio; it is
attributed to decrease in hydroxyl groups caused by PVA ratio
decrease. The inter- and inter-molecular bonds of the hydroxyl
groups enhanced the solubility process of the starch/PVA blends in
water. The water immersion causes hydrogen bonds (inter and
intermolecular bonds) to decompose, that increases the film
solubility. Water absorption and capacity of degradability are most
important in biodegradable materials. The results suggest the samples
that have undergone investigation, can be used for shopping, and
food packaging.
The study of soil burial for the sample at (3cm) depth, and at (13cm)
depth has exhibited weight loss increase with soil burial time. The
biodegradability rapidly increases at the first (6-7) weeks; it is found
that the weight loss at (3cm) depth is greater than that at (13cm) that
was attributed to the differences in the availability of oxygen ratio. It
is found that PVA undergoes lowest weight loss, the weight loss
changes with starch, and sugar content. In dry soil, the weight loss is
lower. The results proved that the biodegradation decreases with soil
burial time after seven weeks of burial. It is concluded that the
samples involved are biodegradable material that can be used for
packaging applications and biologically friendly synthetic polymer
blends to solve the solid waste accumulation problem.
The inhibitory behavior of L-Cysteine (Cys) and its derivatives towards iron corrosion through density functional theory (DFT) was investigated. The current research study undertakes a rigorous evaluation of global as well as local reactivity descriptors of the Cys in protonated as well as neutral forms and the changes in reactivity after the combination of Cys into di- and tripeptides. The inhibitory effect of di- and tri-peptides increases since, in the molecular structure, the number of reaction centers increase. We computed the adsorption energies (Eads) and low energy complexes with most stability for the adsorption of small peptides and Cys amino acids onto the surfaces of Fe (1 1 1). We found that the adsorption of tri-peptides onto
... Show MoreRheumatoid arthritis (RA), is an autoimmune, and inflammatory disease that is closely related to the destruction of cartilage and bone. DC-SIGN are important types of C-type lectin receptors (CLRs), expressed on dendritic cells and macrophages, and have a central role in regulating innate and adaptive immunity, function as pattern recognition receptors, and as cell adhesion molecules. Recent evidence has demonstrated that DC-SIGN is involved in the pathophysiological of chronic inflammation, so DC-SIGN has been linked to several autoimmune and may play an essential indicator in the pathogenesis and progression of RA. Therefore, the purpose of this study is to determine the serum level of DC-SIGN in RA patients, as well as the level of DC
... Show MoreA new four series of 2,2′-([1,1′- phenyl or biphenyl]-4,4′-diylbis(azanediyl)) bis(N′-((E)-1-(4-alkoxyphenyl) ethylidene) acetohydrazide) [V-XI]a,b and 1,1′-(2,2′-([1,1′- phenyl or biphenyl]-4,4′-diyl bis(azanediyl)) bis- (acetyl)) bis(3-(4-ethoxyphenyl)-1H-pyrazole-4-carbalde hyde) [XII-XVIII]a,b have been synthesized by varying terminal lateral alkoxy chain length (n = 1–3, 5–8), central linkage group (phenyl or biphenyl) and induced pyrazole heterocyclic ring in the main chain. The last two series were synthesized by the cyclization of substituted acetophenone hydrazones with Vilsmeier–Haack reagent (DMF/POCl3) to produce 4-formylpyrazole derivatives. The chemical structures of the synthesized compounds were examine
... Show MoreAbstract: Facial defects resulting from neoplasms, congenital, acquired malformations or trauma can be restored with facial prosthesis using different materials and retention methods to achieve life-like look and function. A nasal prosthesis can re-establish aesthetic form and anatomic contours for mid-facial defects, often more effectively than by surgical reconstruction as the nose is relatively immobile structure. For successful results, lot of factors such as harmony, texture, color matching and blending of tissue interface with the prosthesis are important. The aim of this study is to describe the non-surgical rehabilitation with nasal prosthesis for an Iraqi patient who received rhinectomy as a result of squamous cell carcinoma of the
... Show MoreThe study aims to identify the concept of empowering women from the point of view of experts in the Palestinian society, specifically in Gaza, as well as to explore the foundations of their formation of this concept. Additionally, the study seeks to clarify the most important challenges facing the empowerment of women in Palestinian society. The study used the design of a grounded theory that seeks to build the theory through deep analysis of the data, as qualitative data were collected through holding two focus groups and six in-depth interviews with the study sample, who were selected by the method of targeted sampling. The sample included (16) individuals (9 female experts, 7 male experts) holding academic and community leadership pos
... Show MoreThe main goal of this in vivo study was to evaluate the effect of 532nm Q-switched Nd: YAG Laser in combination with Human Serum Albumin 20% concentration (as a welding aid) on the liver tissue repair clinically, and histologically. The animals used in this study were 21 male rabbits divided into three main groups: control group (3 rabbits), conventionally treated group (9 rabbits) and Laser treated group (9 rabbits). Each two main groups (conventional and laser treated) consist of three sub-groups depending on the response evaluation at three different periods. The Laser group was treated using 532nm Q-switched Nd: YAG laser after adding human serum albumin immediately on the incised liver’s tissue. The energy of was 460mJ, and 4Hz fr
... Show MoreMost researchers concentrate their studies on the design, stress and pressure distributions of the prosthetic socket. A little attention is considered for the stiffness of the various materials of the prosthetic sockets. Prosthetic laminated sockets in Iraq are costly to be manufactured while polypropylene socket is relatively cheap in comparing with the laminates.
Experimental study is conducted to compare the stiffness of five prosthetic sockets made of different materials. Compression, three point flexural and tensile tests are implemented by the Testometric machine. The laminate sockets give better results in compression than polypropylene. Polypropylene gives good results in bending compared with the laminate sockets. When t
... Show MoreHydrogen sulfide removal catalyst was prepared chemically by precipitation of zinc bicarbonate at a controlled pH. The physical and chemical catalyst characterization properties were investigated. The catalyst was tested for its activity in adsorption of H2S using a plant that generates the H2S from naphtha hydrodesulphurization and a unit for the adsorption of H2S. The results comparison between the prepared and commercial catalysts revealed that the chemical method can be used to prepare the catalyst with a very good activity.
It has observed that the hydrogen sulfide removal over zinc oxide catalyst follows first order reaction kinetics with activation energy of 19.26 kJ/mole and enthalpy and e
... Show MorePharmaceutical companies assign a budget for activities and promotions that aim to change the prescription habits of the physicians to choose the most suitable medications for their patients, which will eventually grow their sales. The study's objectives were to explore physicians' and medical representatives' perspectives on the criteria of impactful professional PP and the factors influencing the interaction between physicians and medical representatives. Qualitative in-depth interviews with flexible probing techniques were carried out in 2023. A semi-structured, open-ended interview questionnaire was used to interview physicians and medical representatives (MRs) from different private clinics in several governorates in Iraq. Ten physicia
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