Chromatography Method for Simultaneous Determination of Five Synthetic Dyes by High Performance Liquid Chromatography

An effective analytical method for the simultaneous determination of five synthetic colorants (i.e., Tartrazine, Brilliant Black, Sunset yellow, Brilliant Blue and Erythrosine) in wine by Reversed-Phase High-Performance Liquid Chromatography with a Diode Array detector was established. The experimental parameters, including the spectrophotometric properties, detection limits and recoveries of studied synthetic colorants, were studied in detail. These parameters were determinated according to statistical methods.Under optimized conditions, the recoveries for all experimental samples were in the range of 98.03–103.5%, and this method had good linearities in the tested ranges with correlation coefficients (r2) >0.9991. The limits of quantification for five synthetic colorants were between 0.054 and 0.1 mg.L−1. Keywords: synthetic dyes, high performance liquid chromatograph

Edge-disjoint Linkages in Infinite Graphs

The main subject of this thesis is the infinite graph version of the weak linkage conjecture by Thomassen [24]. We first prove results about the structure of the lifting graph; Theorems 2.2.8, 2.2.24, and 2.3.1. As an application, we improve the weak-linkage result of Ok, Richter, and Thomassen [18]. We show that an edge-connectivity of (k+1) is enough to have a weak k-linkage in infinite graphs in case k is odd, Theorem 3.3.6. Thus proving that Huck's theorem holds for infinite graphs. This is only one step far away from the conjecture, which has an edge-connectivity condition of only k in case k is odd. As another application, in Theorem 4.2.7 we improve a result of Thomassen about strongly connected orientations of infinite graphs [25], in the case when the infinite graph is 1-ended. This brings us closer to proving the orientation conjecture of Nash-Williams for infinite graphs [15]

The Reality of the Meetings of the Academic Councils at Naif Arab University for Security Sciences and its obstacles

The study aimed to identify the reality of following the modern methods in the meetings of the academic councils in Naif Arab University for Security Sciences and its obstacles. The number of the study society reached 102 members of the academic councils in the university. The researcher used the method of the comprehensive sample and using the descriptive method, On the ground, the questionnaire was used to identify the views of the study community on the answer to the three axes of the study, using the Statistical Package Program (SPSS) for analysis and statistical processing. The study reached many conclusions, including: The objectives of the meeting are determined accurately, and the place and time of the meeting are determined in the invitation, and emergency meetings are called when necessary. Delegations are delegated to members, and decisions are taken after consultation with the experts at the meeting. The meeting is concluded on time and to a medium extent of the responses of the study community. Lack of incentives for active members. And the results of the meeting do not send a written letter to the participants, the results of the study showed that the overlap between administrative and academic practices and individual decision-making, the absence of material and moral incentives for members and the lack of a specific time for the end of the meeting are one of the most important difficulties facing the management of meetings. The study reached several recommendations, including: the need to delegate powers to members participating in meetings. Decisions must be made after consultation with the meeting specialists. The need to end the meeting in time for him to stay away from the waste of time. Physical and moral incentives should be provided to the active members of the meetings as they have a significant impact on increased attention and activity in the implementation of the decisions of the meetings. Keywords : Meetings, Academic Councils, Security Sciences DOI: 10.7176/EJBM/12-3-07 Publication date: January 31st 2020

التنمية الاقتصادية كمدخل لإعادة إحياء البلدة القديمة بمدينة غزة

"Gaza old city currently faces tremendous environmental, cultural and social challenges resulting from the rapid urbanization and ongoing societal transformation. In countries suffered from conflicts such as Palestine, it becomes clear that political and security conditions are considered as an additional factor that would accelerate deterioration process in old cities. Introducing sustainable development planning in post-conflict situations is a crucial step for sound urban development and can contribute to creating a more stable, peaceful and prosperous society. It also allows for effective coordination of donor assistance as well as more efficient use of limited local physical, human, technical and financial resources. The main objective of this paper is to propose a practical method to achieve sustainable development in Gaza old city. The framework of proposed approach is that sustainable development is more likely to succeed depending on upgrading commercial routes and open spaces. In addition, it is suggested that Gaza old city needs a specific body (planning unit) which suggested being quasi-governmental. Applying this approach on Al-Kissariya Market showed that thorough improvements on the physical elements of the urban fabric are required to enhance the commercial activities and revitalize the economic role of the old city of Gaza in the development impact on the local society. "التنمية الاقتصادية كمدخل لإعادة إحياء البلدة القديمة بمدينة غز

Fabrication of a Novel (PVDF/MWCNT/Polypyrrole) Antifouling High Flux Ultrafiltration Membrane for Crude Oil Wastewater Treatment

The present work deals with the fabrication of novel poly(vinylidene fluoride) (PVDF)/Multi-wall Carbon Nanotubes (MWCNT)/Polypyrrole (PPy) ultrafiltration membrane by phase inversion technique for the removal of crude oil from refinery wastewater. In situ polymerization of pyrrole with different concentrations of MWCNT ranging from 0.025 wt.% to 0.3 wt.% in PVDF prepared solutions. Measurement of permeability, porosity, contact angle, tensile strength, zeta potential, rejection studies and morphological characterization by scanning electron microscopy (SEM) were conducted. The results showed that membrane with (0.05% MWCNT) concentration had the highest permeability flux (850 LMH/bar), about 17 folds improvement of permeability compared to pristine PVDF membrane. Moreover, membrane rejection of crude oil reached about 99.9%. The excellent performance of this nanocomposite membrane suggests that novel PVDF modification with polypyrrole had a considerable effect on permeability with high potential for use in the treatment of oily wastewater in the refinery industry

Cellulose Acetate Membranes: Fouling Types and Antifouling Strategies—A Brief Review

Cellulose acetate (CA) is a semisynthetic, biodegradable polymer. Due to its characteristics, CA has several applications, including water membranes, filament-forming matrices, biomedical nanocomposites, household tools, and photographic films. This review deals with topics related to the CA membranes, which are prepared using different techniques, such as the phase inversion technique. CA membranes are considered very important since they can be used as microfiltration membranes (MF), ultrafiltration membranes (UF), nanofiltration membranes (NF), reverse osmosis (RO) membranes, and forward osmosis (FO) membranes. Membrane fouling results from the accumulation of materials that the membrane rejects on the surface or in the membrane’s pores, lowering the membrane’s flux and rejection rates. There are various forms of CA membrane fouling, for instance, organic, inorganic, particulate fouling, and biofouling. In this review, strategies used for CA membrane antifouling are discussed and summarized into four main techniques: feed solution pretreatment, cleaning of the membrane surface, membrane surface modification, which can be applied using either nanoparticles, polymer reactions, surface grafting, or surface topography, and surface coating

Cellulose Acetate Membranes: Fouling Types and Antifouling Strategies—A Brief Review

Cellulose acetate (CA) is a semisynthetic, biodegradable polymer. Due to its characteristics, CA has several applications, including water membranes, filament-forming matrices, biomedical nanocomposites, household tools, and photographic films. This review deals with topics related to the CA membranes, which are prepared using different techniques, such as the phase inversion technique. CA membranes are considered very important since they can be used as microfiltration membranes (MF), ultrafiltration membranes (UF), nanofiltration membranes (NF), reverse osmosis (RO) membranes, and forward osmosis (FO) membranes. Membrane fouling results from the accumulation of materials that the membrane rejects on the surface or in the membrane’s pores, lowering the membrane’s flux and rejection rates. There are various forms of CA membrane fouling, for instance, organic, inorganic, particulate fouling, and biofouling. In this review, strategies used for CA membrane antifouling are discussed and summarized into four main techniques: feed solution pretreatment, cleaning of the membrane surface, membrane surface modification, which can be applied using either nanoparticles, polymer reactions, surface grafting, or surface topography, and surface coating