The electrospun nanofibers membranes (ENMs) have gained great attention due to their superior performance. However, the low mechanical strength of ENMs, such as the rigidity and low strength, limits their applications in many aspects which need adequate strength, such as water filtration. This work investigates the impact of electrospinning parameters on the properties of ENMs fabricated from polyacrylonitrile (PAN) solved in N, N-Dimethylformamide (DMF). The studied electrospinning parameters were polymer concentration, solution flow rate, collector rotating speed, and the distance between the needle and collector. The fabricated ENMs were characterized using scanning electron microscopy (SEM) to understand the surface morphology and estimate the average fiber sizes. The membrane porosity percentage was measured using the dry-wet weight method. Also, a dynamic mechanical analyzer was used to determine the mechanical strength properties (tensile strength and Young's modulus) (DMA). The obtained results revealed that the polymer concentration and flow rate mainly affect the porosity and fiber size in ENMs. Increasing the polymer concentration improves the strength and flexibility, while the flow rate did not show a clear effect on the mechanical strength of ENMs. Both fibers collecting speed and spinning distance did not clearly impact the membrane morphology. ENMs flexibility significantly increased with increasing the collector speed and decreasing the spinning distance. Strong and flexible ENMs with small fibers can be fabricated using 10% PAN/DMF at a flow rate of 1 mL/h, collector speed of 140 rpm, and spinning distance of 13 cm.
This study, which is considered the first of its kind in the world and the Arab homeland, was carried out in the laboratory of mushroom production belonging to the Medicinal Plant Unit/ College Of Agricultural Engineering Sciences/ University of Baghdad during the period from July 21, 2016, to December 30, 2018, aiming to isolate and purify the mycelium of the wild isolation in addition to the genetic and morphological identification of the mushroom Agaricus bellaniae. The obtained pure isolation was tagged in the American National Center for Biotechnology Information (NCBI) with symbol MF987843.1, thus Iraq would be the second country in the world in which the mushroom is grown following the United States of America. The
... Show MoreThe concept of forming the living space in the American strategic thought has an
important position it is regarded as an strategic movement that it supports the American
United States with the huge capabilities in its own concern that enables it to approach of
American administration , we find that of different historical periods it works to establish that
the geopolitical dimension which is accompanied with the ability of American response for
the evens that in its own turn enables the American united states to seize the growing chances
in the global strategic environment This study includes five chapters :
- Chapter one: The idea of living space.
- Chapter two: Geopolitical dimension of living space theory.
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The variability of Candaharia levanderi (Simroth, 1902)(Gastropoda, Stylommatophora, Parmacellidae) in two biotopes (southern and northern slopes, the Kampirtepa gorges, the Kugitang Tau ridge) has been investigated using polymerase chain reaction (PCR) with the implementation of primers, the 18S DNA of the region is amplified, the variability (sharply differing in color) of two populations of C. levanderi is studied .
The first population is in the suburbs of Namangan, (Namangan Region); the second population is in Kampirtepa gorges, Kugitang Tau ridge (Surkhandarya Region). It is established that, most often, the variability of morphological signs is observed on the coloration of mollusks. The development of body coloration is an ad
In this research, a group of gray texture images of the Brodatz database was studied by building the features database of the images using the gray level co-occurrence matrix (GLCM), where the distance between the pixels was one unit and for four angles (0, 45, 90, 135). The k-means classifier was used to classify the images into a group of classes, starting from two to eight classes, and for all angles used in the co-occurrence matrix. The distribution of the images on the classes was compared by comparing every two methods (projection of one class onto another where the distribution of images was uneven, with one category being the dominant one. The classification results were studied for all cases using the confusion matrix between every
... Show MoreBackground: Sclerotherapy is a simple treatment modality for treatment of infantile hemangioma and slow-flow vascular malformations; Polidocanol is a mild sclerosing agent that is traditionally used in treatment of varicose veins. This study aims to evaluate the effectiveness, treatment outcome, and complications of polidocanol foam sclerotherapy for infantile hemangioma and slow-flow vascular malformations. Materials and methods: Between March 2013 and December 2014, seventeen patients with infantile hemangioma and slow-flow vascular malformations treated with polidocanol 1% foam sclerotherapy. Foam was prepared by Tessari’s method. Injection performed under general or local anesthesia, injections were repeated (if necessary) on mon
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