Dhanraj T. Masram

New class of phosphine oxide donor-based supramolecular coordination complexes from an in situ phosphine oxidation reaction or phosphine oxide ligands.

A one-pot, multicomponent, coordination-driven self-assembly approach was used to synthesize the first examples of neutral bridging phosphine oxide donor-based supramolecular coordination complexes. The complexes were self-assembled from a fac-Re(CO)3 acceptor, an anionic bridging O donor, and a neutral soft phosphine or hard phosphine oxide donor.

Metal complex of the first-generation quinolone antimicrobial drug nalidixic acid: structure and its biological evaluation.

A novel binuclear squire planar complex of nalidixic acid with Ag(I) metal ion with the formula [Ag(Nal)2] has been synthesized. The synthesized metal complex was characterized using CHN analysis, Fourier-transformed infra-red (FT-IR), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), ultra violet–visible (Uv–vis) and single-crystal X-ray diffraction (XRD). The newly synthesized complex shows more advanced antifungal activity compared to the parent quinolone against four fungi, namely Pythium aphanidermatum, Sclerotinia rolfsii, Rhizoctonia solani and Rhizoctonia bataticola.

Synthesis, Characterization and Thermal Degradation Study of Terpolymer-derived from p-Hydroxybenzoic Acid, Diaminonaphthelein with Formaldehyde

Resin pHDNF has been synthesized by the condensation of p-hydroxybenzoic acid and diaminonaphthelein with formaldehyde in the presence of catalyst hydrochloric acid in 1 : 1 : 2 molar proportions of reactants. The purity of newly synthesized terpolymer has been tested and confirmed by the thin layer chromatography (TLC) technique. Detailed thermal degradation studies of the pHDNF resin have been carried out to ascertain its thermal stability. The thermal degradation curve was examined in order to determine their mode of decomposition, order of reaction, apparent activation energy, frequency factor, free energy change, entropy change and apparent energy change. The Freeman—Carroll and Sharp—Wentworth methods were applied for the calculation of kinetic parameters and the data from the Freeman—Carroll method was been used to determine various thermodynamic parameters. The terpolymer resin was characterized by elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and UV-visible spectral studies. The number-average molecular weight of the resin was determined by non-aqueous conductometric titration.

Synthesis of resin I: salicylic acid, hexamethylene diamine and formaldehyde and its ion-exchange properties

Abstract The terpolymer resin salicylic acid-hexamethylenediamine-formaldehyde (SHMF) was synthesized by the condensation of salicylic acid and hexamethylenediamine with formaldehyde in the presence of a hydrochloric acid catalyst. The number average molecular weight of the resin was determined by non-aqueous conductometric titration. Terpolymer resin was characterized by elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and UV- Visible spectral studies. Chelation ion exchange properties have also been studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+ and Pb2+ions employing a batch equilibrium method. It was employed to study the selectivity of metal ion uptake involving the measurements of distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study was carried out over wide pH range and in the media of various ionic strengths. The terpolymer showed a higher selectivity for Fe3+, Cu2+ and Ni 2+ions than for Co2+, Zn2+, Cd2+, and Pb2+ ions.

Steric group enforced aromatic cyclic trimer conformer in tripodal molecules

A family of tripodal molecules (1–6) with/without steric ethyl groups at the central benzene scaffold and with furan/thiophene/pyridyl group at the 2-position of the benzimidazolyl unit was synthesised. Compounds 1–6 were characterized by elemental analysis and NMR spectroscopy. Compounds 1, 3, and 5 were further characterized by single crystal X-ray diffraction analysis. The molecular structures of 1 and 4 were optimized using density functional theory (DFT) calculations. X-ray and 1H NMR studies reveal that the introduction of three ethyl groups into a central benzene scaffold of furan/thiophene/pyridyl substituted benzimidazolyl based tripodal molecules enhances the edge-to-face C–H⋯π interactions, thereby favouring the aromatic cyclic trimer motif, in solution and the solid state. The unsubstituted central benzene scaffold allows the furan/thiophene substituted benzimidazolyl units in the tripodal molecules to move freely thereby weakening the edge-to-face C–H⋯π interactions between the aromatic cyclic trimer motif. Molecular modelling calculations indicate that the energy minimized structures of the tripodal molecules adopt a symmetric cyclic aromatic motif conformation.

Synthesis, characterization and antifungal studies of metalloquinolone [Cd2(nal)2(phen)2(Cl)2]

A novel dinuclear, distorted octahedral complex of nalidixic acid (nal) with Cd(II) metal ion with the formula [Cd2(Nal)2(Phen)2(Cl)2] has been synthesized in the presence of N-containing heterocyclic ligand, 1,10-phenanthroline (phen). The synthesized metal complex was characterized using CHN analysis, Fourier transformed infra-red, thermo gravimetric analysis, differential scanning chalorimetry, nuclear magnetic resonance, ultra violet-visible and single-crystal X-ray diffraction. The newly synthesized complex shows more pronounced antifungal activity compared with the parent quinolone against four fungi, namely Pythium aphanidermatum, Sclerotinia rolfsii, Rhizoctonia solani and Rhizoctonia bataticola.

Perfect symmetrical cyclic aromatic trimer motif in tripodal molecule

A noncovalent perfect symmetrical cyclic aromatic trimer motif stabilized through edge-to-face C–H⋯π interactions was found in substituted benzimidazolyl-based tripodal molecule. The distance 4.8 A, centroid to centroid, and interplanar angle 60° between any two aromatic units in the trimer motif are in excellent agreement with the theoretically predicted symmetrical cyclic benzene trimer cluster.

Synthesis, Characterization, and Antifungal Studies of Cr(III) Complex of Norfloxacin and Bipiridyl Ligand.

A novel slightly distorted octahedral complex of Cr(III) of norfloxacin (Nor) with the formula [CrIII(Nor)(Bipy)Cl2]Cl·2CH3OH has been synthesized hydrothermally in the presence of a N-containing heterocyclic compound 2,2′-bipyridyl (Bipy). The complex was characterized with FT-IR, elemental analysis, UV-visible spectroscopy, and X-ray crystallography. Spectral studies suggest that the Nor acts as a deprotonated bidentate ligand. Thermal studies were also carried out. The synthesised complex was screened against four fungi Pythium aphanidermatum (PA), Sclerotinia rolfsii (SR), Rhizoctonia solani (RS), and Rhizoctonia bataticola (RB).

Novel biomaterial: Synthesis and characterization for decontamination of metal from waste water

A spun nanofibers were fabricated by electrospinning of polymer precursor solution containing polyvinyl alcohol/ zinc acetate. Novel ZnO/carbon nanofibers were prepared by annealing the as spun nanofibers in the nitrogen atmosphere. For investigation the effect of carbon presence in the samples, pure ZnO nanofibers were also prepared by annealing the as spun nanofibers in the air. The field emission scanning electron microscopy (FESEM) images indicated the smooth and beadless nanofibers. The wurtzite crystal structure of the nanofibers obtained by using x-ray diffraction (XRD). The band gap energy was estimated by diffuse reflectance spectroscopy (DRS) and Tauc model; and the results revealed band gap narrowing as a result of the carbon presence. Thermal gravimetric analysis (TGA) and differential thermal analysis (DTA) were used to investigate thermal behavior of the samples. Brunauer-Emmett-Teller (BET) data showed the carbon content in the nanofiber reduced the surface areas. The formation of Zn–O and Zn–OH bonds in the nanofiber surfaces was approved by X-ray photoelectron spectroscopy (XPS). The possible photo-degradation mechanism was studied by the examination of photocatalytic property in the presence of tert-butyl alcohol (t-BuOH) and I− anion as •OH radical and hole (h+) scavenger. The results showed that photodegradation of methylene blue molecules occurred by photo-generated electron. The existences of carbon in the nanofibers lead to the photocatalytic activity of the nanofiber under visible light.S and sensing response of pure and indium doped zinc oxide has been reported in this work. We adopted a chemical route to synthesize pure and doped ZnO. We have started with a 0.2M solution of ZnCl2 prepared in distilled water, in this solution indium chloride was added by weight. Then resulting solution was precipitated by adding an ammonium hydroxide drop wise at room temperature. The precipitates thus obtained were separated from rest of the liquids by filtering and were dried into powder at 120oC. Then the powders were sintered at temperature of 500oC for three hours.Double promoted γ-alumina heterogeneous base catalyst (CaO/KI/γ-alumina) was firstly developed for the production of biodiesel from palm oil in refluxed methanol. This study have been conducted in order to improve the activity of single promoted catalyst (CaO/γ-alumina) and to enhance the efficiency of biodiesel production that have been done in the previous work. The CaO/KI/γ-alumina catalyst was prepared by precipitation and impregnation methods. Engineering catalyst done with some parameters that effect on the activity of a catalyst among other: % CaO loading (wt. % against alumina), temperature and time of calcinations. The catalyst was characterized by mean of XRD, and BET methods. The activity of catalyst has been tested by introduced to the transesterification reaction of palm oil. The reaction was carried out in the batch type of reactor (three-neck glass flask with 500 ml capacity) equipped with reflux condenser, thermometer and magnetic stirrer. The result showed that the optimum condition of preparation catalyst (% of CaO loading, temperature and time of calcinations) were 30%, 650°C and 4.5 h, respectively. Under the optimum condition of catalyst, reaction temperature 65°C, reaction time 5 h and oil to methanol molar ratio of 1:42 the biodiesel yield was almost 95%. Therefore, it can be proved that the activity of double promoted catalyst (CaO/KI/γ-alumina) much higher than that the single promoted (CaO/γ-alumina) catalyst.USA gets the lead in nanotechnology and Japan, EU are in pursuit now. Korean government has begun to support the NT based R&D programs since 2001. Korean government supported many research institutions and companies financially to develop nanotechnology. There are much intensive competition to get the governmental fund among many nanocompanies such as SAMSUNG, LG, HYNIX, and many ventures. Korea has got remarkable performance in NT. The 1st half of this study reviews Korean governmental and industrial efforts for NT and evaluates Korean NT by comparing with other countries.M.R.Saber has completed his MSc from Fayoum University, Egypt. He joined Gabbai’s research group at the chemistry department, Texas A&M University, as a Fulbright visiting scholar for 10 months then he started his PhD in the Dunbar research group. He has published 4 papers in reputed journals and participated in several ACS meetings as well as the Austrian Physical Society Meeting 58 [OPG 58]. S Molecule Magnets (SMMs) are a remarkable class of molecules that display magnetic bistability of a molecular origin which arises from the combination of a high ground state electron spin (S) and a large negative zero-field splitting |D|. This magnetic bistability provides an excellent potential for molecular spintronics.We conducted a study of the conductive properties of polyelectrolyte polymer composite based on epoxy binder by electrochemical impedance spectroscopy, depending on the moisture content in it. Varied content of the polyelectrolyte in the polymer matrix and the thickness of coatings on steel substrate.Found that the conductivity of the material depends on its moisture content. The conductivity of the material in air-dry state is 28 MOhm × mm. When moisture content of about 0.5%(wt.) jump in conductivity percolation occurs, its value reaches about 68 KOhm × mm. Found that the coating thickness of 0,15-0,30 mm in the hydrated state allows the material to pass through a cathodic current required for protection of metal density, whereas in the dry state is an insulator. Conductive properties of the investigated polyelectrolyte composite can apply it when infliction to the metal structure before the conductive layer. The function of this layer is to reduce the electrical resistance in the presence of moisture between the coating and the metal structure that promotes the pervasion of cathodic protection current to the protected object, and in the absence of an aggressive environment in the metal to the sheilding, and as a consequence of reducing the cost of consumable cathode current.I the present study, extraction of platinum complexes from leach liquors of spent catalysts in aqua-regia into organic phase by the extractant trioctylphosphine oxide (TOPO) in toluene has been studied. platinum contained in the spent catalysts are leached out from the catalyst matrix by concentrated Hydrochloric acid and Nitric acid as the sole oxidizing agents in the form of chlorocompex [PtCl6] -2. We used alkaline metal salts as additives for enhancement of percentage of [PtCl6] -2 and distribution ratio of Platinum. Besides, effects of various parameters on the distribution ratio of platinum complexes has been investigated. We found KCl as the best alkaline metal salt which could affect both platinum extraction up to 90% and distribution of platinum complex at the desirable directs. Pt extraction had a very slight increase by time after the first half minute. It means that most of the Pt was extracted in the first 30 seconds. Therefore the equilibrium time is less than 30 seconds and the Pt extraction by TOPO is kinetically fast. This fact may resolve the problem of time-consuming extraction of Platinum by other extractants.O of the crack propagation in coatings is very important for the investigation on fracture mechanism. Fracture of plasma sprayed wollastonite coatings was observed in-situ using a Scanning Electron Microscope (SEM) during the Tapered Double Cantilever Beam (TDCB) specimens open. The fracture toughness was obtained subsequently. It is found that the initiation and crack propagation in coatings is discontinuous. The original pores in coatings can guide the cracking somewhat. The local principal stress also can influence the cracking propagation path. The lower fracture toughness of coatings, compared with the corresponding sintered materials, is partially affected by the crack propagating through the existing pores in coatings.N of Poly (amide-co-imide) PAI (torlon)/Poly (trimellitic anhydride chloride-co-4, 4’-methylene dianiline) (PTACM) blends have been prepared by using mechano-electrospinning. Employing mixed solvent systems of DMSO and THF and water coagulation bath as a medium, continuous fibers with improved mechanical properties have been obtained. The continuity of the fibers was strongly dependent on the solvent mixing ratio of DMSO and THF (6:4). Continuous fibers with the most uniform diameter were obtained when a 30% weight ratio of PAI and PTACM (1:1) resins were used in the blending solution. Further these continuous nanofibers were coated with silver nanoparticles via new route using PEG as a binding agent. The mechanical and electrically properties of these fibers dramatically enhanced after coating with silver nanoparticles. The properties of these blends were investigated using a rotational rheometer (AR 2000), SEM, Surface Tension Analyzer, and Universal Testing Machine in an attempt to understand the relationships between their rheological, morphological and mechanical properties.