a borítólapra  Súgó epa Copyright 
European chemical bulletinVol. 2, No. 1 (2013)

Tartalom

Classical chemical sciences

  • W. F. El-Hawary ,
    Faisal Kh. Al-Gethami :

    A simple, new and sensitive spectrophotometric method has been developed for the quantitative determination of the drug Moxifloxacin HCl (MOX), in pure form and in pharmaceutical formulation; and Fe(III) ions. The method was based on the formation of a colored complex between the drug and Fe(III) ions. The maximum absorption wavelength was 450 nm for determination of both MOX and Fe(III) ions. Beer’s law was obeyed in the concentration range of 14.45 – 394.2 μg mL-1 (r2 = 0.998) for determination of MOX and 2.8 – 22.4 μg mL-1 (r2 = 0.97) for determination of Fe(III) ions. The conditions for complex formation were studied and optimized to obtain the highest absorbance available. The method was successfully applied for the analysis of commercial tablets (Maxim), and the recovery study reveals that there is no interference from the common excipients that are present in tablets. The results obtained by the proposed method were compared with that obtained by a standard reference one. Statistical comparison of the results was performed with regard to accuracy and precision using student’s t-test and F-test at 95% confidence level. The results proved that there no any significant difference, regarding accuracy and precision, between the two compared methods.

    Keywords: Spectrophotometry - Moxifloxacin HCl - Iron(III) ions - Complex

  • Tomoko Hayashi ,
    Haruhiko Shibata ,
    Shingo Orita ,
    Takashiro Akitsu :

    We have prepared and characterized several 3d-4f (Ni(II), Cu(II) and Zn(II) transition metal (3d) ions and Ce(III), Pr(III), and Lu(III) lanthanide metal (4f) ions) complexes incorporating chiral Schiff base ligands (abbreviated as CeNi, CeCu, CeZn, PrNi, PrCu, PrZn, LuNi, LuCu, and LuZn, respectively). Solid-state CD spectra and diffuse reflectance electronic spectra exhibited reasonable shift by combination of 3d and 4f ions at charge-transfer region. Magnetic features (antiferromagnetic interactions, if any) also exhibited substitution of 3d-4f ions of diamagnetic or paramagnetic spin numbers. Interestingly, determined crystal structures of some of them exhibited different structural characters about coordination numbers, crystalline solvents, and dimetic (or bridging) features nevertheless of 3d-4f metal substitution in identical organic ligands.

    Keywords: Chirality, Schiff base, Ni(II) complex, Cu(II) complex, Zn(II) complex, Lanthanide complex

Materials and environmental chemistry

  • R. P. Narwal ,
    R. R. Dahiya ,
    R. S. Malik :

    Increasing concentration of pollutant elements due to rapid industrialization and urbanization is now a global problem to soil, plant and animal health and affecting 40 % of the world population. Trace minerals of natural feeds is determined primarily by the mineral composition from the soil and secondly by the actual mineral composition of soil. Widespread deficiencies of Ca, P, Zn and Cu in south Karnataka, excessive Se and Mo in central part of Punjab, Arsenic in lower Indo-Gangetic plains of West Bengal through ground water are causing much toxicity to animal and humans. Clearly, closely linkage of agriculture to animal health must be accomplished if we are to find sustainable solutions to pollutant element deficiencies and associated diet related chronic disease affecting animal health. The deficiency/toxicity of minerals is an area problem. Although, geogenic trace elements toxicities have also caused wide health problems but higher concentration of pollutant elements in soils may lead to an excessive accumulation of metals by plants grown on such soils and may create animal- human health problems. Dysfunctional food systems are mainly responsible for this global crisis in animal- human health. Much of this malnutrition is the result of insufficient intakes of available trace elements in animal’s diets. There are several ways in which agricultural factors can contribute to improve animal nutrition and health. Importantly, agricultural systems are the foundation upon which all nutrients enter into the animal food chain. Only through linking agricultural systems to animal nutrition can sustainable solutions. In this paper strategies and future thrust areas for research and for corrective measures of trace elements deficiencies and improvement of animal’s health are discussed.

    Keywords: Pollutant elements, toxicity in soil, plant, livestock, management and future strategies

  • Kovács Elza ,
    Dario Omanović ,
    Ivanka Pižeta ,
    Halka Bilinski ,
    Stanislav Frančišković-Bilinski ,
    Tamás János :

    In the present study, chemical water quality changes downstream a pool-riffle type stream located at a former Pb-Zn mining site are discussed. The watershed of the Toka stream (Mátra mountain, Hungary) being under rehabilitation is still continuously affected by a neutralised acidic mine drainage, and temporarily, by an abandoned mine tailing. Upstream the AMD confluence which gives the major part of the water flux in dry season, indeed, the stream is of high water quality, while, directly after that, the electric conductivity is app. quintupled, and the pH as well as the trace element concentrations increase, as expected. However, within the range of 10 kilometres, Fe, Zn and Pb concentrations are all remarkably decreased in relation to the distance from the contamination source, and they almost reach the actual background levels. The electric conductivity does not show significant change along the investigated section of the stream, which would indicate dilution. At the same time, presence of amorphous Fe(OH)3 in the sediment is obvious, based on the pH-Eh relations and geochemical analysis, thus the adsorption processes have considerable role in the decrease of trace element concentrations in solution.

    Keywords: abandoned mining site, heavy metal, surface water

  • A. Mani Prakash ,
    A. V. V. S. Swamy ,
    R. Hema Krishna :

    The present study “on the transport related pollutants in the ambient atmosphere and their health impacts on the road side venders of the Indian city” has been carried out at Punjagutta station. The ambient air quality was measured in this traffic station and the monthly means were recorded. A 24 h cycle of hourly sampling was also carried out to assess the peak hour traffic concentrations of the ambient air quality parameters. The concentrations of Total Suspended Particulate Matter (TSPM), Respirable Suspended Particulate Matter (RSPM), Sulphur Dioxide (SO2), Oxides of Nitrogen (NOx) and Carbon Monoxide (CO) were monitored and compared with the national standards. The behaviour of the quality parameters of this station was described. It has been well established that the time of exposure and dose of the pollutants were positively correlated. The study included vendors who have been staying in the place for not less than three years. Monthly mean concentrations of Respirable Suspended Particulate Matter (RSPM) were highest concentration of 154.16 μg m-3 at Punjagutta traffic station during the study period. This concentrations have exceeded the prescribed National ambient air quality (NAAQ) standard for RSPM i.e., 100 μg m-3.Monthly mean concentrations showed a maximum concentration of 6.49 μg m-3 of air of SO2 at Punjagutta. The monthly mean concentrations of oxides of nitrogen (NOx) were recorded at Punjagutta traffic station has shown maximum concentration of 40.16 μg m-3. Highest traffic volumes were recorded at Punjagutta station (44,954) The present study revealed that the pulmonary functioning decreased among 61.5% of the roadside vendors and a considerable shift of the COHb levels in the blood to the higher side was observed in subject samples.

    Keywords: transport emissions, air pollution, exposure assessment, roadside vendors, health hazards

  • Simon László ,
    Szabó Béla ,
    Szabó Miklós ,
    Vincze György ,
    Varga Csaba ,
    Uri Zsuzsanna ,
    Koncz József :

    Basket willow (Salix viminalis L., cv. Inger) and giant reed (Arundo donax L.) energy crops were grown in open-field experiments. The brown forest soil (loamy sand texture, pHKCl 7.5, humus 1.5%, CEC 10.4 cmolc kg-1; As-38.3, Cd-0.11, Cu-12.7, Pb-13.6, Zn-44.3 mg kg-1 in HNO3 - H2O2 extract) was treated with artificial fertilizer and various soil amendments (ammonium nitrateAN: 100, 150, 300 kg ha-1; municipal sewage sludge compostMSSC: 15, 25 t ha-1; municipal biocompostMBC: 20, 25 t ha-1; willow bioashWB: 600 kg ha-1), and with their combination in 4 or 3 replications. Three months later, in the leaves of treated Salix cultures (except WB application) 9.8-23.5% more N was detected than in untreated controls. Most of the treatments enhanced the uptake of K, but concentration of P, Mg, Ca, Fe and Zn in leaves was reduced. Highest As concentrations (1.92-2.11 g g-1) were found in WB-treated cultures. Cd concentration in treated leaves (0.34-0.57 g g-1) was lower than in controls (0.99 g g-1), while Pb concentrations were under the detection limit. Eighteen weeks after first soil treatments with AN, MBC or MSSC mostly MSSC application influenced the accumulation of macro- and micronutrients in the leaves of Arundo, however the observed changes were statistically not significant. Concentrations of toxic Cd and Pb were under the detection limits in all treatments. In spite of the repeated soil application of AN, MBC or MSSC, thirty four weeks later statistically significant changes were not observed in the uptake or accumulation most of the elements (including toxic Cd and Pb) in giant reed shoots.

    Keywords: soil amendments, mineral nutrition, Salix viminalis, Arundo donax, energy crops

  • M. Pandiarajan ,
    S. Rajendran ,
    J. Sathiyabama ,
    J. Lydia Christy ,
    J. Jeyasundari ,
    P. Prabhakar :
    Corrosion inhibitors for concrete corrosion - an overview1-8en [756.90 kB - PDF]EPA-02286-00011-0070

    Reinforced concrete is widely used for building materials and plays a significant role in economic development. However, the premature degradation of reinforced concrete structures due to the reinforcing steel corrosion has become a serious problem in modern society, which results in a huge economic loss. Under normal conditions, reinforcing steel in concrete can be protected from corrosion by forming a compact passive film on its surface in concrete pore solution with high alkalinity (pH 12.5-13.5). However, the passive film can be locally damaged and the localized corrosion of reinforcing steel takes place when pH and/or the chloride concentration at the steel/concrete interface reach the critical values for corrosion. Corrosion behaviour of metals and alloys in concrete solution has been investigated in presence and absence of inorganic and organic inhibitors. Usually carbon steel and steel rebars have been used. Sometimes galvanized steel and SS316L have been used. Organic inhibitors, inorganic inhibitors, and natural products have been used as inhibitors along with concrete admixture. Corrosion resistance of metals has been evaluated by weight loss method, electrochemical studies such as polarization study and AC impedance spectra. Galvanostatic pulse technique has also been employed. The protective film formed on the metal surface have been analyzed by SEM, FTIR spectroscopy, XPS, AFM and EDAX. The protective film consists of metal-inhibitor complex, calcium carbonate and calcium hydroxide. Experiments have been carried out at room temperature. Corrosion inhibitors fill up the pores and prevent the penetration chloride ion towards the metal surface. Passive films formed on the metal surface also increase the life time of concrete rebars.

    Keywords: corrosion inhibitors, concrete

Biochemistry, molecular biology and biotechnology

  • Bódi Éva ,
    Fekete István ,
    Andrási Dávid ,
    Kovács Béla :

    Trace mineral selenium is an essential nutrient of fundamental importance to human biology, therefore it is very important to be in our daily diet. Although it is known that selenium content of foods show wide variety, the most commonly consumed food have low selenium content. The main object of our work is to study the enrichment of selenium during germination of wheat and pea (Triticum aestivum and Pisum sativum) because we are of the view based on previous studies that the sprouts are able to take up element high in concentration. Sprouting was chosen because it additionally enhances the nutritional value of seeds, for example, by a higher vitamin content, a better quality of protein, and some other parameters. We dicided to combine this with higher selenium content. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the total element concentration. After determining the element, we calculated the percent of selenium which was found in sprouts treated with Se, may cover our daily need. With regards to our experiments, we concluded that, selenium are good for the treatment of sprout because the 0.1 mg dm-3 selenium treatment contribute to cover our daily need of selenium needs.

    Keywords: selenite, selenate, wheat- and pea sprout, ICP-MS

Industrial and engineering chemistry

  • Liu Shu ,
    You Hongju :

    Classification and preparation of the emulsifying wax have been discussed in the present article. The emulsifying wax is classified into four types of wax such as the cationic emulsified wax, the anionic emulsified wax, the non-ionic emulsifying wax and the amphoteric ionic type emulsified wax based on the properties of surfactant. Further, there are four types of preparation methods for the emulsifying wax are available such as the method of emulsifying agents dissolving in the water, the second in dissolving in the oil, the primary soap method and the taking turns adding method have been introduced also. Effects of the reaction conditions such as choosing the different emulsifying agents, the stirring speed, the emulsifying time and the ratio of emulsifying agents to wax on the emulsifying wax preparation have also been explained.

    Keywords: overview; wax; preparation; emulsion

  • Liu Shu ,
    You Hongju :

    In the present article the effects of different reaction conditions on the synthetic method of isopropyl chloroacetate have been reviewed. Different catalysts that consist of inorganic salt like (Ce(SO4)2·4H2O and NaHSO4) and PCl3 have also been introduced. The reaction conditions include the reaction time, the molar ratio of chloroacetic acid to isopropanol, the amount of the catalyst and the number of reusable catalyst. The optimized reaction time, the molar ratio of chloroacetic acid to isopropanol and the amount of the catalyst are beneficial to improve the yield of isopropyl chloroacetate.

    Keywords: effect; reaction conditions; synthesizing; isopropyl chloroacetate