The first bis(orotato–N,O) complex: Synthesis,crystal structure,spectroscopic and thermal characterization of (chaH)2[Cu(HOr–N,O)2(cha)] · 2H2O (cha = cyclohexylamine and HOr = orotate(2−))

The novel bis(cyclohexylaminium) cyclohexylaminebis(orotate–N,O)cuprate(II) dihydrate, (C₆H₁₅N)₂[Cu(C₅H₂N₂O₄)₂(C₆H₁₄N)] · 2H₂O, has been prepared and characterized by elemental analysis, magnetic measurements, FT-IR and UV–Vis spectroscopy, thermal analysis and X-ray diffraction. The Cu(II) complex crystallizes in the monoclinic space group P2₁/c. The copper atom in the five-coordinated (chaH)₂[Cu(HOr–N,O)₂(cha)] · 2H₂O is chelated by a deprotonated pyrimidine nitrogen atom and carboxylate oxygen atom as a bis(bidentate) ligand and the cyclohexylamine ligand completes the square-pyramidal coordination. The thermal decomposition of the complex has been predicted by the help of thermal analysis (TG, DTG and DTA).     

Vitamin B13 Complexes of Nickel(II) and Copper(II) with Ethanolamine: Syntheses,Crystal Structures,Spectroscopic and Thermal Studies

Fac‐bis(ethanolamine)orotatonickel(II), [Ni(HOr)(ea)₂] and mer‐bis(ethanolamine)orotatocopper(II) dihydrate, [Cu(HOr)(ea)₂]· 2H₂O were synthesized and characterized by elemental analysis, FT‐IR, UV‐Vis Spectroscopy and thermal analysis. In addition, their solid‐state structures were determined by single crystal X‐ray diffraction studies. Both the fac‐[Ni(HOr)(ea)₂] (1) and mer‐[Cu(HOr)(ea)₂]·2H₂O (2) complexes are isomorphous and crystallize in the triclinic space group . The Ni²⁺ and Cu²⁺ ions are coordinated by two neutral ea ligands and one orotate dianion in a distorted octahedral fashion. The ea ligand acts as a bidentate donor through the amine N and hydroxyl O atoms, while orotate dianion is coordinated through deprotonated N3 pyrimidine atom and carboxylate oxygen atom as a bidentate ligand. Thermal decompositions of the complexes are studied in over the range 20–600 °C on heating in a static air atmosphere.     

Synthesis,Spectral, Thermal and Structural Characterization of mer‐Triaquaorotatoquinoxaline Cadmium(II) Dihydrate

The new orotate complex of cadmium(II) with quinoxaline, mer‐[Cd(HOr)(H₂O)₃(QX)]·2H₂O, was synthesized and characterized by elemental analysis, FT–IR spectroscopy, thermal analysis and single crystal X–ray diffraction techniques. The complex crystallizes in the triclinic system, space group . The Cd²⁺ ion exhibits a distorted octahedral coordination by one bidentate orotate, one monodentate quinoxaline and three aqua ligands. The uncoordinated water molecules link the orotate, quinoxaline and aqua ligands via O–H···O, O–H···N hydrogen bonds. Thus, an extensive network of hydrogen bonds stabilizes the crystal structure and form an infinitive three dimensional lattice. The decomposition reaction takes place in the temperature range 20–700 °C in the static air atmosphere.     

The electrochemical behavior of some podands at a benzo[c]cinnoline modified glassy carbon electrode

This paper describes the grafting of benzo[c]cinnoline (BCC) molecules on glassy carbon (GC) electrode surface. The attachment of BCC molecules to carbon substrate is induced by the electrochemical reduction of the corresponding diazonium salt. The modification of GC with BCC diazonium salt was done in aprotic solution and proved by blocking of dopamine electron transfer. The presence of BCC at the GC surface was characterized by cyclic voltammetry and X-ray photoelectron spectroscopy (XPS). On modified surface, the electrochemical behavior of two different types of podands and the catalytic effects of the GC-BCC surface were studied. The XPS was used to monitor element characteristics of the adsorbates on the GC surface and confirm the attachment of BCC molecules to the GC surface.     

Enhanced ethanol sensing properties of WO3 modified TiO2 nanorods

Pristine and WO₃ decorated TiO₂ nanorods (NRs) were synthesised to investigate n-n-type heterojunction gas sensing properties. TiO₂ NRs were fabricated via hydrothermal method on fluorine-doped tin oxide coated glass (FTO) substrates. Then, tungsten was sputtered on the TiO₂ NRs and thermally oxidised to obtain WO₃ nanoparticles. The heterostructure was characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy. Fabricated sensor devices were exposed to VOCs such as toluene, xylene, acetone and ethanol, and humidity at different operation temperatures. Experimental results demonstrated that the heterostructure has better sensor response toward ethanol at 200 °C. Enhanced sensing properties are attributed to the heterojunction formation by decorating TiO₂ NRs with WO₃.     

Characterizations of Riesz spaces with b-property

A Riesz space E is said to have b-property if each subset which is order bounded in E^~~ is order bounded in E. The relationship between b-property and completeness, being a retract and the absolute weak topology |σ|(E^~, E) is studied. Perfect Riesz spaces are characterized in terms of b-property. It is shown that b-property coincides with the Levi property in Dedekind complete Frechet lattices.      

Eisenstein series and convolution sums

The Ramanujan Journal - We compute Fourier series expansions of weight 2 and weight 4 Eisenstein series at various cusps. Then we use results of these computations to give formulas for the...     

Forced oscillation of second-order nonlinear differential equations with positive and negative coefficients

In this paper we give new oscillation criteria for forced super- and sub-linear differential equations by means of nonprincipal solutions.     

Electrochemical Determination of the Effect of Caffeic Acid onto the Interaction between Idarubicin and DNA by Single‐use Disposable Electrodes

Now it is well known, antioxidant may affect the interaction of anticancer drugs and DNA. This study aims to investigate the interaction between Idarubicin and DNA and the effect of caffeic acid on this interaction. Disposable, inexpensive, easy handle electrodes were used in this study to investigate the interaction of idarubicin and DNA electrochemically. Idarubicin (IDR) is an anthracyline antitumor antibiotic, which used against one or more types of leukemia. Electrochemical behaviour of IDR was investigated by using cyclic voltammetry. The interaction between anticancer drug, IDR and calf thymus double‐stranded DNA (ctdsDNA) was investigated by using differential pulse voltammetry (DPV) technique in the absence and presence of caffeic acid.     

Spectroscopic characterization of charge-transfer complexes of morpholine with chloranilic and picric acids in organic media: Crystal structure of bis(morpholinium 2,4,6-trinitrocyclohexanolate)

Electron donor–acceptor interaction of morpholine (morp) with chloranilic acid (cla) and picric acid (pa) as π-acceptors was investigated spectrophotometrically and found to form stable charge-transfer (CT) complexes (n–π*) of [(Hmorp)₂(cla)] and [(Hmorp)(pa)]₂. The donor site involved in CT interaction is morpholine nitrogen. These complexes are easily synthesized from the reaction of morp with cla and pa within MeOH and CHCl₃ solvents, respectively. ¹HNMR, IR, elemental analyses, and UV–vis techniques characterize the two morpholinium charge-transfer complexes. Benesi–Hildebrand and its modification methods were applied to the determination of association constant (K), molar extinction coefficient (?). The X-ray crystal structure was carried out for the interpretation the predict structure of the [(Hmorp)(pa)]₂ complex.