Co-occurrence of the Cyanotoxins BMAA, DABA and Anatoxin-a in Nebraska Reservoirs, Fish, and Aquatic Plants
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Publication Date
Sat Sep 01 2018
Journal Name
Polyhedron
Novel dichloro (bis {2-[1-(4-methylphenyl)-1H-1, 2, 3-triazol-4-yl-κN3] pyridine-κN}) metal (II) coordination compounds of seven transition metals (Mn, Fe, Co, Ni, Cu, Zn and Cd)
The 1
3-dipolar cycloaddition “click” reaction between an azide and an alkyne to give a 1
2
3-triazole was reported by Huisgen in 1961 [1]. In 2002 the Copper(I)-catalyzed Azide-Alkyne Cycloaddition (CuAAC) to prepare a 1
2
3-triazole was reported [2]
[3]. The existence of relatively basic nitrogen atoms in the 1
2
3-triazole rings
and the possibility of introducing additional donor groups in the substituents (Fig. 1)
made the CuAAC “click” reaction an attractive method to prepare differently substituted 1
2
3-triazoles. These compounds have been used as ligands to coordinate to various metal ions that display a range of applications such as in electrochemical and photochemical studies
in supramolecular chemistry
magnetism
metal-ion sensing and catalysis [4]. The reasons for the success of the “click” reaction
is that it is easy to carry out and is widely applicable. It is not affected by a variety of functional groups
and can be carried out with a variety of Cu(I) catalysts and solvents
including aqueous conditions. The Cu(I) catalysts overcome the high activation energy barrier of the non-catalyzed Huisgen reaction by changing the mechanism of the reaction. A large variety of copper catalysts can be used for the CuAAC reaction
on condition that the maximum concentration of Cu(I) species is generated during the reaction. The pre-catalyst can be a Cu(II) salt (usually CuSO4) together with a reducing agent (often sodium ascorbate) or a Cu(I) compound in the presence of a base or amine ligand and a reducing agent to prevent oxidation to Cu(II). Some strong oxidising cupric salts or complexes such as Cu(OAc)2 also work. The solvent is very flexible from organic to aqueous
with the most commonly used combination water + an alcohol (t-BuOH
MeOH or EtOH). The key role of the solvent or solvent mixture is to solubilize the substrates and Cu(I) catalyst in order to ensure rapid reactions. Such aqueous conditions are very useful for biochemical conjugations
as well as for organic syntheses.
We recently reported on the synthesis of a series of differently substituted 1
2
3-triazole chromophores
the substituted 2-(1-phenyl-1H-1
2
3-triazol-4-yl)pyridine ligands [5]
see Fig. 2 middle
with substituents R = H (L1)
CH3 (L2)
OCH3 (L3)
COOH
F
Cl
CN
CF3
O(CH2)3CH3 and N(CH3)2. These versatile ligands were found to coordinate to various first row transition metals
such as manganese
cobalt and nickel [6]. Here we extend the series to include more first row transition metal(II) coordination compounds
iron
copper and zinc
as well as a second row transition metal(II) coordination compound
cadmium
containing the 2-(1-(4-methyl-phenyl)-1H-1
2
3-triazol-1-yl)pyridine chromophore (Fig. 2 right with R = CH3). This series of seven novel coordination compounds is the first series of pyridyl-triazole based transition metal coordination compounds where seven different transition metals are coordinated to the same 1
2
3-triazole chromophore
namely 2-(1-(4-methyl-phenyl)-1H-1
2
3-triazol-1-yl)pyridine.
Publication Date
Sun Oct 01 2017
Journal Name
Al–bahith Al–a'alami
Employ of Public Relations in Building Awareness of Security against Terrorism A Survey of the Employees of the Directorate General of Public Relations and Media at the Ministry of Interior
Employment
Public Relations
Identity Building
Security
Counterterrorism
Relationships and Media 'Researches
Master Thesis
This study aims at identifying the role played by Public Relations in the field of security awareness of the dangers of terrorism. The research is directed to the employees at the Directorate General of Public Relations and Media at the Ministry of Interior. And that on the basis that those who play an important role in the security awareness are the security institutions, primarily the Ministry of Interior, since this Directorate is responsible for all subjects related to the public security using public relations science. It aims at identifying the functions, methods and communication tools used by the Directorate to raise awareness about the dangers of terrorism. In order to achieve the research objectives, the researcher uses the sur
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Publication Date
Sat Apr 01 2017
Journal Name
Al–bahith Al–a'alami
Digital Communication: The Future of Identity in Arab TV Drama: A Field Study on a Sample of Arab Society in the UAE in 2017
Digital Communication
of Identity in Arab
TV Drama
Arab
UAE
The digital communication of a product of communication and information revolution. It is characterized by accurate and comprehensive in its services and its effects, which brought changes in the structure of many communities and their organizational structures. They have significant impacts on the social systems and social relations, especially in the Arab societies, which are the focus of the globalized Western media, for many reasons: economical, political , cultural and social.
According to this perception, the Arab identity has become in an encounter with big challenges by the globalized media of trade and the media, which aims to achieve greater profits because of identity and its importance to the communities. This occurs par
Publication Date
Mon Aug 19 2024
Journal Name
Journal Of Metastable And Nanocrystalline Materials
The Structural, Magnetic, and Electrochemical Properties of Composite PAni/Co<sub>0.2</sub>Mn<sub>0.8</sub>Fe<sub>2</sub>O<sub>4</sub>
The current work concerns preparing cobalt manganese ferrite (Co0.2Mn0.8Fe2O4) and decorating it with polyaniline (PAni) for supercapacitor applications. The X-ray diffraction findings (XRD) manifested a broad peak of PAni and a cubic structure of cobalt manganese ferrite with crystal sizes between 21 nm. The pictures were taken with a field emission scanning electron microscope (FE-SEM), which evidenced that the PAni has nanofibers (NFs) structures, grain size 33 – 55 nm, according to the method of preparation, where the hydrothermal method was used. The magnetic measurements (VSM) that were conducted at room temperature showed that the samples had definite magnetic properties. Additionally, it was noted that the saturation magnetizatio
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Publication Date
Mon Dec 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Banking Governance According to the principles of the Basel Committee and its impact on the achievement of the strategic objectives of banks Study in a sample of private commercial banks Iraqi
Banking Governance
principles
strategic objectives .
This study aims to impact statement played by banking governance according to the decisions of the Basel Committee in achieving the strategic objectives of the banks, But order to achieve the this goal has been the adoption of two hypotheses in addition to the two main hypotheses as sub answered preliminary The study seeks to verify their health and two (no correlation relationship and impact between Banking governance and achieve strategic objectives), has been tested hypotheses. Study has reached
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Publication Date
Tue Jan 01 2008
Journal Name
J Bagh College Of Dentistry
A comparative study of the sealing ability of two different
obturation techniques with and without the use of sealers.
Obturation techniques
sealer
microleakage
Background: The final stage of endodontic therapy is complete obturation of the root canal system to provide as perfect as possible at the cementodentinal junction of the apical foramen. The purpose of this in vitro study was to evaluate the sealing ability of injection molded thermoplasticized gutta percha and lateral condensation techniques with and without the use of sealers. Materials and Methods: Forty freshly extracted adult human maxillary central incisors with complete formed apices were utilized in this study. The teeth were randomly divided into four groups for evaluation of the apical seal. Group (1) lateral condensation gutta percha technique without sealer, (2) lateral condensation gutta percha technique with sealer, (3) Inject
... Show MorePublication Date
Sat Nov 12 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The relationship of salary localization and the growth of bank deposits: (applied research for a sample of private banks)
domiciliation of salaries
bank deposits
electronic payments
The research problem consisted in answering the question that revolves around whether there is a relationship to the settlement of salaries with the growth of bank deposits? The research also aimed to provide some initial solutions to improve the role of salary localization, in terms of reviewing the concept of electronic payment systems, its tools and channels, and then identifying the concept of salary localization, its importance, objectives and obstacles to its application, and then analyzing the reality of the state of the settlement of salaries and bank deposits for the research sample banks, which are each of the bank (Ashur International, Business Bay, the Iraqi Middle East for Investment, the Iraqi National, Development and the
... Show MorePublication Date
Sat Apr 13 2024
Journal Name
مجلة واسط للعلوم الریاضیة
The development of the leading Arab scouting movements and their role in the development of youth and society
History of sports
scouting movement
Arab scouting
comprehensive development
youth
the history of the Scouting movement reflects the global social cultural and technological change over more than a century. scouting aims to develop young people worldwide through educational programs based on specific principles and values. in arab countries, the scouting movement is considered one of the most important platforms contributing to developing young people and enhancing their rule. positive in society, began with the establishment of the first Scout camp in the region and witnessed great growth and prosperity over the decades the research reveals the historical roots and development of the scout movement in the leading arab countries and analyzes the positive impact of scout movement in the leading arab countries on the develo
... Show MorePublication Date
Mon Apr 08 2024
Journal Name
Fifth International Conference On Applied Sciences: Icas2023
Bifurcation analysis of the role of good and bad bacteria in the decomposing toxins in the intestine with the impact of antibiotic and probiotics supplement
Gut bacteria model
probiotics and antibiotics affects
Stability analysis
This study presents a mathematical model describing the interaction of gut bacteria in the participation of probiotics and antibiotics, assuming that some good bacteria become harmful through mutations due to antibiotic exposure. The qualitative analysis exposes twelve equilibrium points, such as a good-bacteria equilibrium, a bad-bacteria equilibrium, and a coexisting endemic equilibrium in which both bacteria exist while being exposed to antibiotics. The theory of the Sotomayor theorem is applied to study the local bifurcation around all possible equilibrium points. It’s noticed that the transcritical and saddle-node bifurcation could occur near some of the system’s equilibrium points, while pitchfork bifurcation cannot be accrued at
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Publication Date
Sat Feb 02 2019
Journal Name
Journal Of The College Of Education For Women
Adultery in the Ancient near east from the standpoint of the customs and traditions and the old laws
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