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1
Content available Growth and boichemical contents of Cowpea (Vigna unguiculata L.) on the application of zinc
100%
Ganesh K. S. , Selvaraju M.
World Scientific News
|
2015
|
tom 16
53-63
EN
The present investigation deals with the effect of zinc on the morphological and biochemical parameters of Cowpea (Vigna unguiculata L) under laboratory condition. The Cowpea plants are grown in petriplates lined with filter paper treated with various concentrations (control, 10, 25, 50, 75, 100, 150 and 200 ppm) of zinc. The experiments were replicated five times. The various morphological parameters such as germination percentage, shoot length, root length, root nodules, total leaf area, fresh weight and dry weight of the plants were measured. Similarly the biochemical contents such as chlorophyll, carotenoid, protein and Sugar was analyzed. The results indicated that the various morphological and biochemical parameters increased up to 50 ppm and decreased at high levels of zinc.
2
Content available Plant extract as biodegradable inhibitor for zinc in dilute solution of sulphuric acid
88%
Onukwuli O. D. , Ezeugo J. O.
World Scientific News
|
2018
|
tom 109
195-210
EN
The inhibitive action of the ethanol extract of oil from Picralima nitida leaf, towards acid corrosion of zinc, is tested using weight loss, and thermometry methods. It was found that the extract acted as a good corrosion inhibitor for zinc corrosion in 0.5 M H2SO4 solution. The inhibitive action of the extract was discussed in view of Langmuir adsorption isotherm. It was revealed that the adsorption of the extract on zinc surface is governed by spontaneous process. The inhibition efficiency (IE) increases in line with corresponding increase in extract concentration. The temperature effect of the corrosion inhibition on the IE was studied. Revelation from the studies indicates that the presence of extract increases the activation energy of the corrosion reaction. Furthermore, from the calculated thermodynamic parameters, it was observed that Picralima nitida extract provides a good protection to zinc against pitting corrosion in chloride ion containing solutions.
3
Content available Optimization of corrosion inhibition of Picralima nitida leaves extract as green corrosion inhibitor for zinc in 1.0 M HCl
88%
Ezeugo J. N. O. , Onukwuli O. D. , Omotioma M.
World News of Natural Sciences
|
2017
|
tom 15
139-161
EN
Herein, the optimization of inhibitive action of the ethanol extract of oil from Picralima nitida leaves, towards acid corrosion of zinc, was tested using weight loss and thermometry methods. We found that the extract acts as a good corrosion inhibitor for zinc corrosion in 0.1 M HCl solutions. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm. This revealed that spontaneous processes govern the adsorption of the extract on zinc surface. Herein, the inhibition efficiency (IE) increases in line with corresponding increase in extract concentration. The temperature effect of the corrosion inhibition on the IE was also studied. This indicated that the presence of the extract increases the needed activation energy of the corrosion reaction. Furthermore, in our work, an optimal inhibition efficiency IE (%) of 86.78 was obtained at optimum inhibitor concentration of 1.2 gl-1, optimum temperature and time of 313 k and 8 hrs, respectively. From the calculated thermodynamic parameters, it can be said, then, that Picralima nitida extract provides good protection to zinc against pitting corrosion in chloride ion containing solutions.
4
Content available remote Zinc-containing bioactive glasses for bone regeneration, dental and orthopedic applications
88%
Balasubramanian P. , Strobel L. A. , Kneser U. , Boccaccini A. R.
Biomedical glasses
|
2015
|
tom 1
|
nr 1
EN
Zinc is a vital and beneficial trace element found in the human body. Though found in small proportions, zinc performs a variety of functions in relation to the immune system, cell division, fertility and the body growth and maintenance. In particular, zinc is proven to be a necessary element for the formation, mineralization, development and maintenance of healthy bones. Considering this attractive attributes of zinc, recent research has widely focused on using zinc along with silicate-based bioactive glasses for bone tissue engineering applications. This paper reviews relevant literature discussing the significance of zinc in the human body, along with its ability to enhance antibacterial effects, bioactivity and distinct physical, structural and mechanical properties of bioactive glasses. In this context, even if the present analysis is not meant to be exhaustive and only representative studies are discussed, literature results confirm that it is essential to understand the properties of zinc-containing bioactive glasses with respect to their in vitro biological behavior, possible cytotoxic effects and degradation characteristics to be able to effectively apply these glasses in bone regeneration strategies. Topics attracting increasing research efforts in this field are elaborated in detail in this review, including a summary of the structural, physical, biological and mechanical properties of zinc-containing bioactive glasses. This paper also presents an overview of the various applications in which zinc-containing bioactive glasses are considered for use as bone tissue scaffolds, bone filling granules, bioactive coatings and bone cements, and advances and remaining challenges are highlighted.
5
Content available remote Removal of zinc ions as zinc chloride complexes from strongly acidic aqueous solutions by ionic exchange
88%
Gîlcă E. , Măicăneanu A. , Ilea P.
Open Chemistry
|
2014
|
tom 12
|
nr 8
821-828
EN
The aim of this study was to compare several anion exchangers and to investigate the capacity of Amberlite IRA410 to remove zinc as chloride [ZnCl3]− from hydrochloric solutions (1 M). Influence of the process parameters such as stirring rate, resin quantity and zinc initial concentration over the removal process, was considered. The highest experimental ionic exchange capacity between the considered anionic exchangers, in the same working conditions (500 rpm, 5 g resin and 500 mg L−1), was obtained for Amberlite IRA410, 8.34 mg g−1. With an increase of zinc ions concentration, ionic exchange capacity increased up to 19.31 mg g−1 (1100 mg L−1). The experimental data were analysed using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. The results were also analyzed using sorption kinetics models, pseudo-first-, pseudo-second-order, intra-particle and film diffusion models. From the Dubinin-Radushkevich and Temkin isotherm models the mean free energy and heat of sorption were calculated to be 7.45 kJ mol−1, respectively 1×10−4 kJ mol−1, which indicates that zinc sorption is characterized by a physisorption process. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model.
6
Content available Trace metals analysis of soil and edible plant leaves from abandoned municipal waste dumpsite in Owerri, Imo state, Nigeria
88%
Ibe F. C. , Beniah O. I. , Enyoh C. E.
World News of Natural Sciences
|
2017
|
tom 13
27-42
EN
Municipal refuse may increase heavy metal concentration in soil, even at low levels, and their resulting long-term cumulative health effects are among the leading health concerns all over the world. In this study, we investigated the concentration of heavy metals in soils and edible plant leaves grown in an abandoned dumpsite along Akachi road in Owerri municipality. The soil samples were collected at each plot using a soil auger at the depth of 0-10 cm. Leaves of dominant edible plant species were selected and collected from each sample plot. The samples were dried in an oven with forced air at 40 °C, milled to fine powder then digested with 10 ml concentrated HNO3 and 5 ml concentrated HClO4 and were analyzed for Cr, Cu, Fe, Mn, Al, and Zn, using an H183200 MultiParameter Bench Photometer. Result showed that metals in in the sampled soils included (in order of quantity) Cr: 150-280 >Fe: 116.50-203 >Cu: 12.4-18.8 >Mn: 0-20 >Al: 0.08-0.16 >Zn: 0-1.4 mg kg-1 Dw. Moreover, levels of metals in the edible plant leaves are in the order of: Zn>Fe>Cu>Al>Mn>Cr. Zn, in particular, was higher than FAO/WHO recommended limits. Still, application of Pollution Load Index and Ecological risk models showed that the area is unpolluted and safe for use. Daily Metal Intake estimates indicated that zinc is mostly consumed from the plant species. The trends in Transfer Factor for the heavy metal in vegetable samples studied were in order: Zn>Al>Cu>Mn>Fe>Cr. Therefore, abandoned solid waste dumpsites contained significant concentrations of heavy metals which are later absorbed and accumulated by plants growing it.
7
Content available remote Concentrations of retinol, α-tocopherol, copper, zinc and iron in plasma of young subjects differing in their engagement in motor activities
88%
Malara M. , Hübner-Woźniak E. , Kurczyńska A.
Biomedical Human Kinetics
|
2012
|
tom 4
1-5
EN
Study aim: To assess possible effects of gender and of the level of motor activity on the deficiencies of selected vitamins and minerals in young subjects.Material and methods: Four groups of physical education (PE) students (n = 15 each) were studied: sedentary men (SM) and women (SF), and physically active men (AM) and women (AF) engaged in endurance sports, all aged 18 - 24 years, were studied. Somatic measurements included body height and mass, and body fat content (by Durnin's method, from 4 skinfolds), the biochemical ones included concentrations of retinol, α-tocopherol, copper, zinc and iron in plasma.Results: Men had significantly higher retinol (p<0.05) and iron (p<0.01) levels than women. The AM and SF groups had significantly (p<0.05 - 0.01) higher plasma levels of copper and zinc than Group SM. Group AF had lower zinc levels than Groups AM and SF, that latter group having lower α-tocopherol compared with Group SM.Conclusions: Inasmuch the observed differences could be due to the respective intakes, the effect of motor activity and the associated increased elimination of minerals could not be ruled out.
8
Content available Changes in Biochemical Variations of Sesuvium portulacastrum under Copper and Zinc Treatment
75%
Kalaikandhan R. , Vijayarengen P. , Mathivanan S.
World Scientific News
|
2018
|
tom 92
|
nr 2
139-154
EN
The present work deals with the ecophysiological studies on the biochemical contents of the effect of copper and zinc on Sesuvium portulacastrum L. The Sesuvium portulacastrum plant are grown in pots in a spilt plot design with copper and zinc concentration levels as main treatments (control, 100, 200, 300, 400, 500 and 600 mg/kg-1). The experiments were replicated five times. The Sesuvium portulacastrum plants are raised in pots. The copper and zinc were mixed with (1:2) the sand and applied to the pot soil (10 kg /acre). The two heavy metals copper and zinc were applied in the soil mixed. Pots were irrigated as and when necessary. The plant samples were analyzed at four different intervals (30, 60, 90 and 120th DAS). The results indicates that the heavy metals (copper and zinc) application, at the six rates (100, 200, 300, 400, 500 and 600 mg kg-1) caused reduction in various biochemical contents such as (Amino acid, Proline, Protein, Total sugar and Starch) when applied copper and zinc. Increasing in various bio chemical contents such as (Amino acid, Proline, Protein, Total Sugar and Starch) copper 200 mg kg-1, zinc 300 mg kg-1 only increased low concentration and higher concentration is decreased the all biochemical contents Sesuvium portulacastrum.
9
Content available Heavy metals in the waters of Dąbie Lake (North-West Poland) in the years 2008-2012
51%
Daniszewski P.
World Scientific News
|
2017
|
tom 69
75-85
EN
Heavy metal pollution is an ever increasing problem of our lakes. These toxic heavy metals entering in aquatic environment are adsorbed onto particulate matter, although they can form free metal ions and soluble complexes that are available for uptake by biological organisms. The increase in residue levels of heavy metal content in water, sediments and biota has resulted in decreased productivity and increase in exposure of humans to harmful substances. Many of these metals tend to remain in the ecosystem and eventually move from one compartment to the other within the food chain. Food chain contamination by heavy metals has become a burning issue in recent years because of their potential accumulation in biosystems through contaminated water, soil, sediment and air. The Dąbie Lake is an integral part of the River Odra estuary. It is a shallow (2.5 m mean depth) water body with two distinct basins: the large (Dąbie Wielkie) and the small (Dąbie Małe). The aim of the studies, carried out in the years 2008 - 2012, was to determine the content of Cadmium (Cd), Chromium (Cr), Copper (Cu), Mercury (Hg), Nickel (Ni), Lead (Pb) and Zinc (Zn) in the waters of Dąbie Lake, being the internal part of the tertiary Odra estuary. The range of observed concentrations (ppm) for the analysed metals was between: maximum concentration of Cd was 0.97 ppm and the minimum was 0.42 ppm; maximum concentration of Cr was 0.28 ppm and the minimum was 0.12 ppm; minimum concentration of Cu was 0.04 ppm and maximum of 0.08 ppm; maximum concentration of Hg was 0.07 ppm and the minimum was 0.03 ppm; minimum concentration of Ni was 2.29 ppm and maximum of 2.97 ppm; maximum concentration of Pb was 0.09 ppm and the minimum was 0.04 ppm; minimum concentration of Zn was 2.85 ppm and maximum 3.94 ppm.
10
Role of the exopolysaccharides of Nostoc linckia (Cyanophyta) in accumulation of metal ions from the environment
51%
Shnyukova E. I.
Acta Physiologiae Plantarum
|
2007
|
tom 29
|
nr 1 Suppl.
11
Content available Characterization of Ca50Mg20Zn12Cu18 Alloy
44%
Hrapkowicz B. , Lesz S. T.
Archives of Foundry Engineering
|
2019
|
tom iss. 1
75--82
EN
The Ca50Mg20Zn12Cu18 was assessed with different methods in order to characterize its basic characteristics, and to determine whether the amorphous alloy of such composition would be applicable as an implant material. The XRD analysis was conducted to conclude the structure of the initial material. The Ca50Mg20Zn12Cu18 ingot sample demonstrates crystalline structure containing two main intermetallic phases, however as-cast plates show features of an amorphous material, revealing the characteristic amorphous halo on the x-ray patterns. It was confirmed by the scanning electron microscopy method and fracture images revealing chevron pattern morphology with shell type fracture. Corrosion resistance, was studied using the potentiostatic analysis. The amorphous samples show higher resistance than the crystalline one. Post corrosion surface of the Ca50Mg20Zn12Cu18 alloy exhibits high concentration of magnesium and calcium hydroxides, forming the globular structures in large aggregates of spherical units.
12
Content available Characterization of Ca50Mg20Zn12Cu18 Alloy
38%
Hrapkowicz B. , Lesz S. T.
|
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