A new ligand type (O2) [2,3-O-diacetyl-5,6-O-benzylidene L- ascorbic acid] [L] and its complexes of general formula [M(L)2(X)(Y)]Cln (where: M=CrIII ,X=Y=H2O, n=3; CoII, X = Y = 0, n= 2; NiII and CuII, X = Cl, Y = H2O, n= 1; ZnII, X = Y = H2O,n = 2) are reported. The ligand was prepared in two steps; first step involved the synthesis of [5,6-O-benzylidene-L-ascorbic acid] (A). In second step derivative-A was then reacted with acetyl chloride and anhydrous pyridine as a base to give the titled ligand. Metal complexes of the ligand with CrIII,CoII,NiII,CuII and ZnII were synthesised by direct reaction of the corresponding metal chloride with the ligand[L] in a 2L:1M mole ratio. The ligand and its complexes were characterised by spectroscopic methods 1H NMR, FTIR, (UV-Vis), atomic absorption, microanalyses, chloride content, melting point and conductance measurements . These studies revealed that the geometry about CrIII, NiII,CuII and ZnII is octahedral while the complex of CoII adopts a tetrahedral geometry.
The increasing requirement and use of dental implant treatments has rendered dental implantology indispensable in dentistry. The aim of this study is to determine the optimum concentration of calcium silicate to be incorporated into a polyetherketoneketone (PEKK) matrix used as an implant material to enhance the bioactivity and mechanical properties of the composite compared with unmodified PEKK. In this study, different weight percentage (wt%) of micro-calcium silicate (m-CS) is incorporated into PEKK with ethanol as a binder. Subsequently, the mixture is dried in a forced convection oven at 120°C and poured into customized molds to fabricate a bioactive composite via compression molding (310°C, 15 MPa, and 20 min holding time
... Show MoreThe concept of transitional justice is newly emerging, as it was mainly associated with addressing issues of serious breaches and abuses of human rights during conflicts and situations resulting from violence and the use of force in societies that are in the process of democratization, as transitional justice aims primarily to restore civil peace and rebuild institutions The state needs multidimensional justice: a judicial system that achieves the rule of law, corrective restoration of the wounds of the past, and a distributive characteristic of the redistribution of wealth.
يمثل الأخذ بالنظام الفيدرالي أطاراً تنظيمياً لشكل الدولة و مرحلة تحول مهمة في بنية الدولة العامة في مختلف مجالاتها، فالانتقال من المركزية في أدارة الشؤون العامة للدولة الى النمط الفيدرالي يمثل تحولا بنيوياً وسيكولوجياً ،حيث يكون هنالك توزيع مكاني - عمودي للسلطة والثروة بين الوحدات المكونة للدولة بشكل يختلف كليا عن الحالة المركزية، ونجد صور تنظيمية عديدة تتأسس ضمن اطار الفيدرالية العام ،
... Show MoreA quadruped (four-legged) robot locomotion has the potential ability for using in different applications such as walking over soft and rough terrains and to grantee the mobility and flexibility. In general, quadruped robots have three main periodic gaits: creeping gait, running gait and galloping gait. The main problem of the quadruped robot during walking is the needing to be statically stable for slow gaits such as creeping gait. The statically stable walking as a condition depends on the stability margins that calculated particularly for this gait. In this paper, the creeping gait sequence analysis of each leg step during the swing and fixed phases has been carried out. The calculation of the minimum stability margins depends up
... Show MoreSince the advent of the sunrise of the immortal message, Islamic legislation has always established justice and the right guidance, and has prevented any perversion, injustice or corruption, with a divine system that called in its course the characteristics of the legislation on its general basis and its ability to develop, progressivity, and paving the way with a collective approach, accompanied by the worldly and moral punishment. When the corrupters went too far, reformers were delayed and values were missed; Mankind has been afflicted with the scourge of injustice and loss, and has lost sight of the approach that the Creator of the world has given to the people of the world, for what would guide them in their affairs sooner and later
... Show MoreA OUI,tiper of LWW lig_;:tnds .of ppen sides. of Bis-'Oxad1azoJe· and·
Bis-triazole derived from dichloroetbane and [Bis 0-ohloro et!:ty)
= :=:: =
ether)] (BCEE)' wersynthesi:zed. These inelude: 1, 4- bis[-3{thio- 2 -
. (Chloro·ethyl)l1 1;4 - oxadiazole ......$yl] butane (-L I);1 4 B'is {phenl-
3{th
... Show MoreSolvent- free thermal heating, one-pot condensation of acetophenone, ethyl cyanoacetate or malononitrle and substituted Aromatic aldehyde, ammonium acetate give, 2oxo-3-cyano-4-substituted Aryl-6-phenyl pyridine [I]a-h , or 2-amino-3-cyano-4-substituted Aryl-6-phenyl pyridine derivatives[II]a-f , respectively. Treatment of compounds 2-oxo-3-cyano-4-substituted Aryl-6-phenyl pyridine with phosphorous penta sulphide (P2S5), give 2-thioxo-3-cyano-4-substituted Aryl-6-phenyl pyridine derivatives[III]a-c . All prepared compounds
... Show MoreHerein, the interfacial polymerization method has been used for the synthesis of PPy/NaVO3 composites with different compositions of NaVO3 (10 %, 20 %, 30 %, 40 % and 50 %) as an efficient electrode material for supercapacitors. The successful formation and composition of the as-prepared composites (PV1-PV5) were confirmed by FTIR, XRD, EDX, and SEM analysis. The electrochemical properties were investigated by cyclic voltammetry (CV), galvanometric charge–discharge measurement (GCD), and electrochemical impedance spectroscopy (EIS) in 0.5 M H2SO4 electrolyte. As compared to other, the PV4 composite exhibit excellent specific capacitance of 391 F g−1 at a current density of 0.75 A/g with good cycling stability of ∼59 % after 1000 cycle
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