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.
In this manuscript, the effect of substituting strontium with barium on the structural properties of Tl0.8Ni0.2Sr2-xBrxCa2Cu3O9-δcompound with x= 0, 0.2, 0.4, have been studied. Samples were prepared using solid state reaction technique, suitable oxides alternatives of Pb2O3, CaO, BaO and CuO with 99.99% purity as raw materials and then mixed. They were prepared in the form of discs with a diameter of 1.5 cm and a thickness of (0.2-0.3) cm under pressures 7 tons / cm2, and the samples were sintered at a constant temperature o
... Show MoreThe evaluation and efficiency and effectiveness of account system for the department of delegation and cultural Relationships in the center of ministry of higher Education and Scientific research Considered as a very important and active subjects in the modification of accounting system in this department and to develop it and make it able to make available important and accurate information for the planning requirements and monetary and evaluation performance and to make decisions, besides to develop the performance of Iraqi Cultural departments working abroad and to render its role effective to serve the students of higher education in the progressive Countries to facility its growing in scientific and professional and technica
... Show MoreThe present study discusses the significant role of the historical memory in all the Spanish society aspects of life. When a novelist takes the role and puts on the mask of one of the novel’s protagonists or hidden characters, his memory of the events becomes the keywords of accessing the close-knit fabric of society and sheds lights on deteriorating social conceptions in a backwards social reality that rejects all new progressive ideas and modernity. Through concentrating on the society flawing aspects and employing everything of his stored memory, the author uses sarcasm to criticize and change such old deteriorating reality conceptions.
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... Show MoreThis research aims to measure the discrepancy between the accounting income which is prepared according to generally accepted accounting principles and the tax income that is being prepared according to the rules and tax laws, and find out the most important differences that arise between incomes.The research found the most important to the following conclusions:1.Faces determining the tax base for companies subject to income challenges related to the weakness of the efficiency and the possibility of technical angel tax and its ability to examine the financial statements submitted to the tax administration tax.2.That the tax system in Iraq does not comply with accepted accounting principles generally accepted.The research recommends the
... Show MoreThe current research aims to find out ( the effectiveness of the structural model of learning in the acquisition of geographical concepts at the first grade average students ) , and achieving the goals of research has been formulating the null hypothesis of the following :
" There is no difference statistically significant when Mistoi (0.5 ) between the mean scores of the collection of students in the experimental group that is studying the general geographical principles " Bonmozj constructivist learning " and the mean scores of the control group , which is considering the same article ," the traditional way " to acquire concepts.
The researcher adopted th
... Show MoreThe research section tagged (Aesthetics of Abstract Expressionism and its Representations in the Artistic Products of Students of the Department of Art Education) into four chapters and it included in..
The first chapter: (the methodological framework) for the research, and the research problem is summarized through the question (what are the aesthetics of abstract expressionism and its representations in the artistic productions of the students of the Department of Art Education). In the products of students of the Department of Art Education).
The aim of the research was (discovering the aesthetics of abstract expressionism and its representations in the artistic products of the students of the Department of Art Education). As we
The selective information broadcasting service is one of the important services in libraries and information centers, as it is the link between the source and the beneficiary and between related sources, as it links similar sources through keywords and then sends them to beneficiaries, which contributes to reducing the time and effort spent by beneficiaries in obtaining sources or information. Therefore, the application of this service is an important matter and gives a positive indicator in the progress of the library towards the integration of its services. From this standpoint, this research came to answer some questions, including: 1. What are the outlets for beneficiaries (the research community) in obtaining information sources? 2. Wh
... Show MoreEpithelial ovarian cancer is the leading cause of cancer deaths in women. To date, an effective screening tool for ovarian cancer has not been identified Several clinical and biological factors including serum cancer antigen 125 (CA- 125) have been assessed for prognostic and predictive relevance CA-125 is an epithelial marker derived from coelomic epithelium. It is elevated in 90% of advanced ovarian cancers and in 50% of early ovarian cancers while 20% of ovarian cancers have low or no expression of CA- 125 CA-125 concentrations were measured by Mini Vidas test (VIDAS CA125 II / BIOMERIEUX / France). The median CA-125 levels were significantly higher in the sera of ovarian cancer patients than in those with benign tumors an
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