Applied Chemistry

Tri-ethylene (TEG) is used to inhibit the formation of natural gas hydrates in long transportation pipelines that convey gas from remote gas field to processing units. The degradation of glycol leads to its decomposition and reduction of its pH making it more acidic thereby, increasing its tendency to cause corrosion and subsequent blockage of production and transportation facilities. The possible effect of water on tri-ethylene glycol was ascertained in terms of changes in viscosity, pH, density and efflux time as table 1to4.Thus, the resulting effect of water on glycols (TEG) is high at room temperature and low at frozen temperature as was observed in terms of pH, viscosity and efflux time of the mixture.

Three water sample in Oghara Community, Ethiope -West, Nigeria were assessed for Physico-Chemical and heavy metals. The pH of the water ranges from 6.10-8.60, conductivity of water lies between 7.50-77.90?/cm. Total solids, Total alkalinity, hardness, sulphate, ranges from 40.00-50.00mg/1, 28.00-29.70mg/l, 37.00-4.00mg/1, 55.20-5.30mg/I respectively, copper, iron, zinc lies between 0.02 – 0.03mg/I, 0.07-0.08mg/I, 021-0.31mg/I respectively. The results obtained from this study fall within the recommended values specified by NAFDAC and SON except the pH from site C that was above the maximum permissible limits specified by National Agency for Food Drug Administration and Control. (NAFDAC) and Standard Organization of Nigeria (SON).

Some new chalcones, 2-4 bis (tetrahydro - 1,4-oxazine)-6-[4'-{3''-(substituted phenyl) -2''-propenon-1''-yl} phenyl amino]-s-triazine (6a-f) have been achieved by the reaction between 2-4-(bis- tetrahydro- 1,4-oxazine) -6-(4'-acetylphenylamino)-s-triazine (5) and different aromatic aldehydes, which on cyclisation with hydrazine hydrate in presence of acetic acid give acetyl pyrazolines (7a-f). Chalcones (6a-f) on cyclisation with guanidine hydrochloride in presence o f alkali give aminopyrimidines (8a-f). The characterization of newly synthesised compounds has been done on the basis of IR, 1H NMR spectral data as well as elemental analysis. All the synthesised compounds have been screened for their antimicrobial activity.

Drugs normally synthesized to use as medication to treat diseases like cancer and microbial infections, these synthesized drugs were interested more than naturally-derived drugs which have been shows low activity or not as efficient against diseases. A new ligand 3-methylbenzyl (2Z)-2-[1-(pyridin-4-yl)ethylidene]hydrazine carbodithioate (PE3MBC) and its Cd(II), Cu(II), Co(II) and Zn(II) metal complexes. The new ligand and metal complexes were characterized via various physico-chemical and spectroscopic techniques. Cd(II) complex show more activity against microbes and against cancer cell line MCF-7, while other complexes does not shows activity like cadmium complex, all the complexes does not shows any activity against MDAMB-231 cell line. The fatal of the cancer and the microbes cell was due to inhibition of DNA synthesis which was probably due to chelating with metals complexes, or could be referred to lipophilicity, presence of hydrophobic moiety in the complex molecule, also could be due to steric effects and electronic effects.

Malenized Linseed oil and Coconut oil suitable for use in Powder detergent has been synthesized. The reaction conditions such as mole ratio, temperature, time of reaction and use of catalyst have been standardized to get a product with desired HLB ratio, viscosity and solubility. A standard Powder detergent mainly based on malenised vegetables oils and Alpha olefin sulphonate has been prepared. In successive compositions acid slurry has been replaced by neutralized malenized linseed oil by 50 to 100% .A comparison of our maleic based detergents with commercial samples shows that maleic treated oils give excellent foaming, surface tension reduction and detergency properties. The raw material cost of our novel Powder detergents in reasonable and they can be tried on pilot scale and commercial scale production. The special feature of these Powder detergents is freedom from conventional linear alkyl benzene sulphonate and sodium tripoly phosphate so they can be labeled as ecofriendly products for green environment.

The formation of complexes of tolbutamide and Zn(II) was studied in aqueous media at pH 3.4±0.1 by polarography and spectroscopy. The polarogram indicated formation of complexes between tolbutamide and Zn(II). Tolbutamide produces a well-defined direct current polarogram and differential pulse polarogram in 1M KCl (supporting electrolyte) at pH 3.4±0.1. The stoichiometry of the Zn(II)-tolbutamide complex is 1:1. Antidiabetic studies on the drug and its metal complex have been performed in albino mice. Revealing the complex to be more potent in antidiabetic activity compared to the parent drug.

The interaction of transition metal complexes with DNA has long been a subject of intensive investigation with the perspective of development of newer materials for application in biotechnology and medicine. These investigations have resulted in the synthesis of many new metal complexes, which bind to DNA by non-covalent interactions such as electrostatic binding, groove binding and intercalative binding [1,2]. Hence, the current growing interest in small molecules that are capable of binding and cleaving DNA is related to their utility in the design and development of synthetic restriction enzymes, new drugs, DNA foot-printing agents, etc., and also to their ability to probe the structure of DNA itself [3].

Gum Arabic exudate was collected from Acacia Senegal trees around Zaria metropolis. The gum was hydrated in double strength chloroform water, purified in 95% ethanol and then washed with diethyl ether. Modification of the gum was performed with ethanol and Acetic anhydride. Densities of the samples were compared with that of the unmodified gum and it was found that both samples were less dense than the unmodified gum. From turbidity measurement, ethanol modified (EGL) gum appears more turbid than both acetic anhydride modification (AAN) and unmodified gum (PGM). In salinity, conductivity and TDS tests, AAN sample higher values than other samples. The melting point of EGL and PGM are only slightly different, 242oC and 245oC respectively while that of AAN was 229oC. The mechanical properties of the samples were measured using Honsfield Tensometer. The AAN sample has the highest modulus at 10, 20, 30 and 40% gum composition. For PGM the modulus drops from 10-30% gum composition then finally increases. The ACT modification shows decrease in modulus as the percent of gum increases. Modulus of PGM drops at 20, 40, 60 and 80% gum composition. It was found that the tensile strength of the chemical modification formulations reinforced the PVC matrix at 10%/90%, 20%/80% and 30%/70% gum/PVC compositions for AAN and at 10%/90% and 20%/80% gum/PVC compositions. Though EGL showed increase at 30%/70% composition, its tensile strength is similar to that of the unmodified gum (PGM), decreasing with increasing gum concentration.

A selective method for the fast determination of trace amounts of Pb (II)ions in water samples has been developed. method has been developed for preconcentration of Pb on organic-solution-processable functionalized-nano graphene (SPFGraphene) adsorben in the pH range 5.0–10.0, prior to its spectrophotometric determination, based on the oxidation of bromopyrogallol red at ? = 517 nm. This method makes it possible to quantitize Pb in the range of 4.2×10?9 to 2.3×10?5 M, with a detection limit (S/N = 3) of 1.42×10?9 M. This procedure has been successfully applied to determine the ultra trace levels of Pb in the environmental samples, free from the interference of some diverse ions. The precision, expressed as relative standard deviation of three measurements is better than 3.0%.

Sediment and fish (nile Tilapia, Oreochromis niloticus) were collected from six sites of Lake Hawassa namely; Tikur Wuha, Amora Gedel, Dorie Bafana, Central part of the lake, the opposite side of Amora Gedel and Referral Hospital sites. Concentration of heavy metals was analyzed quantitatively using Flame Atomic Absorption Spectrophotometer and Chemometric methods. The maximum and minimum mean levels (mg/kg dry mass) in different lake sediment sites were Cu (51.38-17.64), Mn (348.51-140.63), Cd (12.8764-403), Pb (30.05-6.72), Ni (26.73-8.43 ), Zn (367.84-147.49), Cr (14.15-5.34), Co (27.19-9.59 ), Mg (3859.86-1872.43), Na (4913.72-2903.043), Ca (5526.74 - 3608.71), K (4229.69-2255.57) and that of fish muscle were Cu (13.833-5.666), Mn (11.972-9.722), Zn (21.110-12.055), Ca (574-482), Mg (512-437), Na (771-681), K (903-785). The result shows that the metal concentration in sediment samples is in order of Ca > Na > K > Mg > Zn > Mn > Cu > Pb > Co > Ni > Cr > Cd. The detectable metals in Tilapia fish muscle were in order of K > Na > Ca > Mg > Zn > Mn > Cu. In all the samples, concentrations of metals in sediment samples were higher than those of fish samples.