Two different polyvinyl alcohol/polyvinyl chloride (PVA/PVC) hollow fiber composite nanofiltration membranes were prepared after PVC hollow fiber membranes were coated using dip-coating method with PVA aqueous solution, which was composed of PVA, fatty alcohol polyoxyethylene ether (AEO9), and water [PVA/AEO9/water (4:0.5:95.5) wt%]. Effect of two different PVC hollow fiber immersion times in coating solution were studied. Cross-section, internal and external surfaces of the PVC hollow fibers and PVA/PVC composite nanofiltration membranes structures were characterized by scanning electron microscopy (SEM), pure water permeation flux and solutes rejection. It was found that, the coating layer thickness on the outer surface of the 19 wt% PVC hollow fiber was thin and about (6μm), while the coating solution penetrates through the outer edge of the PVC hollow fiber and it looks like sponge-like structure with increase of the dip-coating time from 20 to 30 sec. Besides, the pure water permeation flux decreases and solutes rejection increases with an increase of the coating time from 20 to 30 sec for the two PVA/PVC composite nanofiltration membranes. Molecular weight cut-off (MWCO) of the PVA/PVC composite nanofiltration membranes were in the range of NF (i.e. 200-3000 Mw).
Abstract:
The problem of the research is that the person face in the starting of his
profession life is to go to the right profession that he or she fits in when the
person enter the works sea many problems appear to him on of them is his
non-accordance with his job ,the research targeted to know the levels of the
accordance of the kindergarten teachers and the relation between the
profession accordance and other like the kind of level and the time of service
and the research worked with (150) kindergarten teachers from the
introductory class and (150) kindergarten teachers from the kindergarten class
for the study year 2008-2009 .
The research been made a measure to get the goal of the research after
the
Abstract:
The issues related to foreign trade is a broad field for discussions and captures the interest of economists for their contribution to the process of economic development in the economies of the countries, especially developing ones. The imports of goods and services in foreign trade constitute an important part of the local by which the economy gets goods and services that the economy cannot produce because of the incompetent base of production. Further, the demand function of imports occupied a good deal of the attention of researchers in the field of international economics for which agricultural imports constitute an important part. The reason for the interest in the subject is due to its im
... Show MoreIncreasing interest in planning at the level of government units as a means to manage the physical and human resources, direct and invest in areas that would include an increase in the economies of the general government units that are part of the general economics of the state.The research problem lies in the introduction of the factors influencing the ongoing expenses that adversely affect the financial planning process at the level of the Ministry of Health Planning, which affects the quality of services provided to citizens, so I sought the researchers to study the reality of financial planning in some of the Ministry of Health and health departments through the analysis of current budgets and diagnose deviations in the implementatio
... Show MoreThis study aimed to determine the optimal conditions for extracting basil seed gum in addition to determine the chemical components of basil seeds. Additionally, the study aimed to investigate the effect of the mixing ratio of gum to ethanol when deposited on the basis of the gum yield which was1:1, 1:2, 1:3 (v/v) respectively. The best mixing ratio was one size of gum to two sizes of ethanol, which recorded the highest yield. Based on the earlier, the optimal conditions for extracting basil seed gum in different levels which included pH, temperature, mixing ratio seeds: water and the soaking duration were studied. The optimal conditions were: pH 8, temperature of 60°C, mixing ratio seeds: water 1:65 (w/v) and soaking duration of 30 min
... Show MoreIn this study, plastic wastes named (PET and PVC) were used to prepare polymer matrix composite (PMC) which can be used in different applications. Composite materials were prepared by mixing unsaturated polyester resin (UP) with plastic wastes, two types of plastic waste were used in this work included polyethylene-terephthalate (PET) and Polyvinyl chloride (PVC) with various weight fractions (0, 5,10,15, 20 and 25%) added as a filler in flakes form. In this work, some of the tests that were carried out included (tensile, bending, and compressive strength) as mechanical tests, in addition to (thermal conductivity and water absorption) as physical tests. The values of tensile, compressive strength and Young's modulus of UP increased after
... Show More<p>The demand for internet applications has increased rapidly. Providing quality of service (QoS) requirements for varied internet application is a challenging task. One important factor that is significantly affected on the QoS service is the transport layer. The transport layer provides end-to-end data transmission across a network. Currently, the most common transport protocols used by internet application are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). Also, there are recent transport protocols such as DCCP (data congestion control protocol), SCTP (stream congestion transmission protocol), and TFRC (TCP-friendly rate control), which are in the standardization process of Internet Engineering Task
... Show MoreGrass trimming operation is widely done in Malaysia for the purpose of maintaining highways. Large number of operators engaged in this work encounters high level of noise generated by back pack type grass trimmer used for this purpose. High level of noise exposure gives different kinds of ill effect on human operators. Exact nature of deteriorated work performance is not known. For predicting the work efficiency deterioration, fuzzy tool has been used in present research. It has been established that a fuzzy computing system will help in identification and analysis of fuzzy models fuzzy system offers a convenient way of representing the relationships between the inputs and outputs of a system in the form of IF-THEN rules. The paper presents
... Show MoreThe research aims to show the role or extent of the impact of financing in its various forms on the municipal performance before and after the financial deficit through relying on the analytical research methodology of the research community represented by the Directorate General of Municipalities and the Directorate of Maysan municipalities as a sample of research (13) municipal institutions for a period of (8) years, Considering the completion of the final accounts of these years, which provides the necessary data for the study, in addition to the variation in the quality and amounts of grants allocated to municipal institutions during these years, which gives a clearer and more comprehensive picture of the reality of allocatio
... Show MoreThe public budget is on the same time an art and a science .As an accountable science it seeks balance between public income and public expenditure for an accountable year. And as an accountable art it seeks to achieve economic balance by distributing equitable income in order to reach sustainable development .This is the optimal use of all natural and human resources to address scarcity of natural resources facing the increase need of human resources by spending on education, health, environment, housing, agriculture and industry to achieve social justice for the current generation and future generations. Since the first budget in Iraq on 1921 an accounting budget, is balancing the sections and items has been adopted and since the publi
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