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. [9] Zinc coatings, A comparative analysis of process and performance characteristics, American Galvanizers Association , 2011, https://www.galvanizeit.org/uploads/publications/Zinc_Coatings.pdf (last visited 4 October 2017

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Dean, C. E., Hargis, B. M. and Hargis, P. S. (1991): Effects of zinc toxicity on thyroid function and histology in broiler chicks. Toxicology Letters 57, 309--318. Effects of zinc

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. Marešová, L. Remenárová, M. Horník, M. Pipíška, J. Augustín, and J. Lesný

Abstract  

The aim of this paper was to obtain quantitative data of foliar uptake kinetics and long distance transport of zinc in tobacco (Nicotiana tabacum L.) and hop (Humulus lupulus L.) plants. Zinc was used as a model of microelement and toxic metal, tobacco and hop as a representatives of agriculturally important plants. A tip of leaf blade was immersed in the solution spiked with 65ZnCl2 and foliar uptake and translocation to other parts of the plant grown in nutrient solution was measured by gamma-spectrometry and autoradiography. We found that foliar zinc uptake by both plants is dependent on the initial metal concentration within the range C 0 = 10–100 μmol dm−3 ZnCl2. Zinc is immobilized mainly in immersed part of the contact leaf and only <1% is transported to non-immersed parts of the leaf. At C 0 = 0.1 mmol dm−3 ZnCl2 concentrations >2.5 mg/g Zn and 4.8 mg/g Zn (dry wt.) in immersed part of tobacco and hop leaf plant, respectively were found after 5 days of exposure. Low mobility of zinc entering the plant via the leaf surface can be attributed to the immobilization of zinc into Zn–ligand complexes with high stability constants log K at pH 6.0–8.0, such as the reaction products of Zn2+ ions with citric acid, histidine or phosphates. Zinc can be extracted from dried leaves by the solutions of inorganic salts, carboxylic acids, amino acids and synthetic complexing ligands such as EDTA. Anionic (SDS) and non-ionic (Tween 40) surfactants causes the decrease of the Zn foliar uptake, but not translocation of Zn from the contact leaf area. Obtained data are discussed from the point of view of possible limited efficiency of liquid formulations designed for practical applications as Zn foliar fertilizers.

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Akhter, P., Akram, M., Orfi, S.D., Ahmad, N. 2002. Assessment of dietary zinc ingestion in Pakistan. Nutrition. 18 :274–278. Ahmad N

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photosynthetic enzymes and zinc deficiencies on Oryza sativa and Pennisetum americanum. Soil Fertil. , 48, 108-149. Photosynthetic activities of C3 and C4 photosynthetic enzymes and zinc deficiencies on Oryza sativa and Pennisetum

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Abstract  

To understand the role of Cu and Zn in human blood both in controls as well as in cardiovascular (CVD) patients, whole blood samples of 181 CVD and 185 controls between the ages of 20–66 years were investigated. Instrumental neutron activation analysis (INAA) and flame atomic absorption spectrophotometric techniques were successfully employed to quantification Cu and Zn levels. The mean blood-Cu levels (1.50 mg L−1) were found as enhanced whereas Zn levels (5.88 mg L −1) were reduced in cardiovascular patients group as compared to 0.90 and 6.70 mg L−1 for Cu and Zn respectively in controls. Cu/Zn ratios for CVD patients are also higher than in control subjects. Negative correlation exists between Cu and Zn levels in both controls and patient groups. However, when the CVD patients were checked for their systolic and diastolic pressure it was found that copper concentrations in these patients was significantly increased (p < 0.001) with the rise of blood systolic pressure so a positive correlation was observed between copper and systolic pressure. Zn on the other hand has an inverse relation with systolic as well as diastolic pressure (p < 0.001). Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, and triglyceride (TG) in blood samples have also been determined and their probable role in the CVD complication has been observed. A positive correlation of blood-Cu with TC, TG, and LDL-C indicates that rise in blood-Cu levels may initiate the development of CVD. An increase in Cu/Zn ratio can instigate the cardiovascular risk factor. The findings from this study can definitely update our knowledge of the role of Cu and Zn in the development of CVD risk in humans.

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Acta Alimentaria
Authors: T. Kośla, M. Skibniewski, E. Skibniewska, and G. Urbańska-Słomka

. Diss. Dr.habil., Fac. Med. Vet., Univ. Leipzig. Koşala, T. (1992): The contens of macro- and microelements in the fodder, blood serum and hair of European bison. Part II. Iron, copper and zinc. Ann. Warsaw

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Orvosi Hetilap
Authors: Klára Szentmihályi, Péter Vinkler, Judit Fodor, József Balla, and Béla Lakatos

Vallee, B. L., Falchuk, K. H.: The biochemical basis of zinc physiology. Phys. Rev., 1993, 73 , 93–195. Falchuk K. H. The

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Ripa S, Ripa R: Zinc and the growth hormone system. Minerva. Med. 87, 25-31 (1996) Zinc and the growth hormone system Minerva. Med

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Introduction The interest in the production of zinc borate has steadily grown because of the great expectations for the applications including polymer additive as flame retardants, the preservative in wood composites and

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