New Schiff-base ligands bearing tetrazole moiety and their polymeric metal complexes with Co(II), Ni(II) and Cd(II) ions are reported. Ligands were prepared in a multiple-step reaction. The reaction of sodium 2,6- diformylphenolate and cyclohexane-1,3-dione with 5-amino-2-fluorobenzonitrile resulted in the isolation of two precursors sodium 2,6-bis((E)-(3-cyano-4-fluorophenylimino)methyl)-4-methylphenolate 1 and 5,5'- (1E,1'E)-cyclohexane-1,3-diylidenebis- (azan-1-yl-1-ylidene)bis(2-fluorobenzonitrile) 2, respectively. The reaction of precursors with azide gave the required ligands; sodium 2,6-bis((E)-(4-fluoro-3-(1H-tetrazol-5- yl)phenylimino)methyl)-4-methylphenolate (NaL) and (N, N'E, N, N'E)-N, N'-(cyclohexane-1,3-diylidene)bis(4- fluoro-3-(1H-tetrazol-5-yl)aniline) (L1). The reaction of these ligands with the appropriate metal ions gave polymeric metal complexes of the formulae {[M2(L)]Cl}n and [M(L1)Cl2]n (where M = Co(II), Ni(II) and Cd(II)). A range of techniques were used to confirm the entity of ligands and their complexes. The formation of ligands and mode of complexation and geometrical structure of the title polymeric complexes were verified using FTIR, electronic spectra, NMR, ESMS, magnetic susceptibility, micro-elemental analysis, metal content, chloride content and conductance. The analytical and spectroscopic data indicated the formation of four-coordinate complexes, with a tetrahedral geometry for Co(II) and Cd(II), and square planer for Ni(II) in L- and L1 complexes. Biological evaluation of ligands and their polymeric complexes against gram-positive bacteria (G+), Bacillus stubtili, Staphylococcus aureus, and gram-negative bacteria (G-), Escherichia coli and Pseudomonas aeruginosa, showed ligands and their polymeric metal complexes have a good effect on the screened bacteria.
In this paper we define and study new concepts of fibrwise totally topological spaces over B namely fibrewise totally compact and fibrwise locally totally compact spaces, which are generalization of well known concepts totally compact and locally totally compact topological spaces. Moreover, we study relationships between fibrewise totally compact (resp, fibrwise locally totally compact) spaces and some fibrewise totally separation axioms.
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War was and remains one of the main instruments for the practice of international relations, and has always been a major focus of the study of international relations. War, such as diplomacy, propaganda, etc., is an instrument of national politics. States have used wars to achieve their goals and aspirations and achieve their national interests. War and peace issues are essential to understanding international relations. They are questions that involve the problem of survival.
Today the term "war" is used in many different ways. We talk about Cold War, Hot War, Limited War, Total War, Conventional War, Unconventional War, Civil War, Gang War, Preventive War etc. However, the war continued to exist, and took various forms.
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One of the most important problems in the statistical inference is estimating parameters and Reliability parameter and also interval estimation , and testing hypothesis . estimating two parameters of exponential distribution and also reliability parameter in a stress-strength model.
This parameter deals with estimating the scale parameter and the Location parameter µ , of two exponential distribution ,using moments estimator and maximum likelihood estimator , also we estimate the parameter R=pr(x>y), where x,y are two- parameter independent exponential random variables .
Statistical properties of this distribution and its properti
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The Civil Rights era has been an era of struggle for the African American in the
Unites states. Thus, many writers devoted their writing to reflect the racism and
discrimination that many have suffered from, among them is Ralph Ellison.
Ralph Ellison is a 20th century African-American writer and scholar best known for
his renowned, award-winning novel Invisible Man. He illustrates the powerful
social and political forces that conspire to keep black Americans in their place,
denying them the right to life, liberty, and the pursuit of happiness guaranteed to all
Americans. Invisible Man is a 1952 novel that addresses many of the social and intellectual
issues facing African-Americans in the twentieth century. It exa
Discourse markers are expressions used to connect sentences to what comes before or after and indicate a speaker's attitude to what he is saying.As linguistic items, they have important functions in discourses of various styles or registers. And being connective elements, discourse markers relate sentences, clauses and paragraphs to each other. "One of the most prominent function of discourse markers, however, is to signal the kinds of relations a speaker perceives between different parts of the discourse". (Lenk 1997: 2) Through political discourse, different types of discourse markers are used. This paper deals with the importance and functions of discourse markers and tries to shed light on the kinds of discourse markers used in polit
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Ferrite with the general formula CuLayFe2-yO4 (where y=0.02, 0.04, 0.06, 0.08 and 0.1), were prepared by standard ceramic technique. The main cubic spinel structure phase for all samples was confirmed by x-ray diffraction patterns with the appearance of small amount of secondary phases. The lattice parameter results were 8.285-8.348 Å. X-ray density increased with La addition and showed values between 5.5826 – 5.7461gm/cm3. The Atomic Force Microscopy (AFM) showed that the average grain size was decreasing with the increase in La concentration. The Hall coefficient was found to be positive. It de |
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It is not available for us to go back in time and see plays old and it plays giants tragedy ancient Greek (Aeschylus, Sofokls, and yourbedes) through the eyes of a generation ago, and if we were able to go back to Ntegathm play it is certain that we will not taste or Nstassig for much of what we see from these offers will not afford the traditional religious rituals, which was accompanied also dance and music in the style of ancient Greek play was representing a large part of the theater see manifestations Can our eyes and ears we twentieth century audience to accept those appearances, and it was then?
Inevitably it will look like a museum bycollection not only. So we find ourselves in the light of the foregoing forced When you do rem
Urban wetlands are one of the complex systems that provide many economic, social and environmental services to the city. In this research, the most important services provided by urban wetlands from the point of view of the urban planner were reviewed, and the types of these lands and their divisions according to the type of services provided by each type were presented. Environmental is represented in its ability to reduce the dangers of floods, mitigate the climate and reduce its negative impacts, purify water and deplete a lot of suspended impurities and pollutants, and social services such as recreational areas and beautiful landscapes that inspire joy and reassurance in the soul, as well as cultural areas and sports activities for m
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We report a method of converting non-conductive plastic surfaces into conductive by plating either copper electroless or copper electroplating -carbon black containing bending Agent onto Perspex plastics . Various approaches have been studied in order to comparing properties of the plated copper for two methods such as scanning electron microscopy (SEM),thickness, roughness, porosity, tensile Strength and elongation. The results show that the surface of electroplating was uniform, compact, and continuous and it had an obvious metallic sheen, while the surface of plated copper for electroless for it had many pores. Also observed that the coating was composed of small cells. Thes
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