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.
The purpose of this study is to show the constants and variables geography in Russian
policy in light of variables geostrategic witnessed by the world, especially after the collapse
of the Soviet Union and the disintegration to fifteen Republic became the Russian Federation
and the heir to the Soviet Union, Geography particularly important because the impact of its
data in policy making less change ofothers, and explain the political choices cannot achieve
security through its relationship constants geographical (natural or human) paint forms of
economic activity and determine the points they national security. issue is the geographical
this or that country is determined by its policy also specifies the way in which
Henrik Ibsen is considered one of the greatest writers on society and its problems in the modern era, as his works deal with society in all its forms in a realistic way, in which he presents the motives and consequences of social problems and their impact on society to study these problems through them to and propose solutions through theatre. Most of his writings were very serious about addressing these social issues. The method of collecting information in the study came through reviewing a group of sources related to realistic theater and social theory, then reading the plays covered in a critical and analytical reading. Based on that, the method of writing this study came and used a group of sources that directly relate to the s
... Show MoreObjective: The aim of this study is to determine the means and the difficulties faced by students of
nursing maternal and child health nursing / College of Nursing / University of Baghdad in obtaining scientific
information in practical training.
Methodology: A purposive sample of (100) Nursing college student - Maternal and Child Health Nursing
Department were selected. Data were collected through the use of the questionnaire form during the
period from the November 2010 to April 2011. Descriptive statistical procedures were used to analyze the
data.
Results: The results showed that the highest percentage of members of the study sample aged between
(20-21 years), females are the most inhabitants of the city of Ba
This study aimed to manufacture an innovative device that enables the player to walk after the operation and improves the functional efficiency through the improvement in the range of motion as well as the improvement in the size of the muscles working on the knee joint. The research, the study population consisted of players with severing the anterior cruciate ligament of the advanced soccer players, and the number of the research sample was (5) injured for the control sample and (5) for the experimental sample in Abu Ghraib Hospital and some rehabilitation centers for a period of six months, and the pre-tests were conducted after two weeks of The cruciate ligament surgery was performed, and the innovative device was used for the e
... Show MoreBackground: Diabetes mellitus consists of a group of diseases characterized by abnormally high blood glucose levels. Glycated haemoglobin (HbA1c) is a form of haemoglobin used to identify the average concentration of plasma glucose over prolonged periods of time. It is formed in a non-enzymatic pathway by normal exposure of hemoglobin to high levels of plasma glucose, The main alterations observed in the saliva of Type 1 diabetic patients are hyposalivation and alteration in its composition, particularly those related to the levels of glucose. The aim of the present study was to assess the effect of Glycated haemoglobin level on the level of salivary glucose which may have an effect on oral health condition. Materials and methods
... Show MoreThe present work determines the particle size based only on the number of tracks detected in a cluster created by a hot particle on the CR-39 solid state nuclear track detector and depending on the exposure time. The mathematical model of the cross section developed here gives the relationship between alpha particle emitting from the (n, α) reaction and the number of tracks created and distribution of tracks created on the surface of the track detector. In an experiment performed during this work, disc of boron compound (boric acid or sodium tetraborate) of different weights were prepared and exposed to thermal neutron from the source. Chemical etching is processes of path formation in the detector, during which a suitable etching solut
... Show MoreIn Iraq, the domestic goat
Extracorporeal shock wave lithotripsy (ESWL) is considered a standard treatment for nephrolith or kidney stones measuring less than 20 mm. Anatomical, machine-related, and stone factors play pivotal roles in treatment outcomes, the latter being the leading role. This paper examined the relationship between stone density on native CT scans and ESWL treatment to remove renal stones concerning several treatments. One hundred and twenty patients (64 males and 56 females) were enrolled and completed the study from April 2019 to September 2020. Inclusion criteria were a single renal pelvis stone of 5–20 mm to be treated for the first time in adult patients with no urinary or musculoskeletal anatomical abnormalities. We assessed patients
... Show MoreNow-a-days the Flexible AC Transmission Systems (FACTS) technology is very effective in improving the power flow along the transmission lines and makes the power system more flexible and controllable. This paper deals with the most robust type of FACTS devices; it’s a Unified Power Flow Controller (UPFC). Many cases have been taken to study how the system behaves in the presence and absence of the UPFC under normal and contingency conditions. The UPFC is a device that can be used to improve the bus voltage, increasing the loadability of the line and reduce the active and reactive power losses in the transmission lines, through controlling the flow of real and reactive power. Both the magnitude and the phase angle of th
... Show MoreThis article presents the simultaneous adsorption of bimetal Cu2+ and Zn2+ from an aqueous solution using activated carbon synthesized from a plum seed precursor by sulfuric acid and microwave activation: plum seeds chemically activated by 45% (w/w) sulfuric acid with 2:1 ratio for 4 h, then carbonized for 2 h at 700 °C and the product obtained activated in a microwave oven for 20 min at 700 W for final of activation. Plum seeds and activated carbon produced were characterized in terms of their physical and chemical composition using Brunauer–Emmett–Teller measurements, field emission scanning electr