Increase In Zinc Content Research Articles

Mg-Zn-Al LDH: Influence of intercalated anions on CO 2 removal from natural gas

Abstract In this study, three components Mg-Zn-Al LDH were synthesized by microwave assisted homogenous precipitation using urea hydrolysis. The physicochemical properties of the prepared solids were evaluated using XRD, FTIR, elemental analysis, surface characterization measurements, and electron microscope. The results indicated the formation of the layered structure containing the three metals in one phase. By controlling the synthesis condition, carbonates as well as nitrogen containing anions were intercalated within the interlayer space of the LDH structure. The type of the nitrogenous species depended on the type and concentration of M (II) cation. The nitrogen adsorption-desorption isotherms were found to be type IV. The specific surface area decreased with increasing zinc content. However, the high specific surface area could be related to inter-particle agglomeration. The TEM images indicated the presence of nanoparticles. The particle size was affected by the concentration of zinc content. The particles of the smallest size (~14–25 nm) were detected in Mg-Zn-Al LDH (Mg:Zn molar ratio = 1:3). The amorphous mixed oxides (LDO) were obtained after the thermal treatment of the as-synthesized LDH at 550 °C. The abilities of the as-synthesized Mg-Zn-Al LDH materials and corresponded LDO to capture carbon dioxide from methane stream were tested using dynamic flow system technique at the ambient conditions of temperature and pressure. The results indicated that the presence of nitrogen containing anions in MgZn(25:75)Al LDH enhance the CO2 adsorption capacity (3.55 mmol/g) relative to its corresponded oxide (3.03 mmol/g).

Effects of dietary zinc source and concentration on performance of growing-finishing pigs reared with reduced floor space

ABSTRACT The objectives of this experiment were to evaluate effects of dietary zinc source (AA complex vs. inorganic) and increasing zinc concentration on growth performance and carcass composition of growing-finishing pigs housed in crowded conditions. Maternal-line barrows and gilts (636 pigs; initial BW = 28.7 kg) were blocked by initial BW and assigned randomly within block to 1 of 5 treatments. Twelve pens were assigned to each treatment over 3 replicate trials. Treatments were (1) control (Con9)—pigs housed in an uncrowded environment (0.73 m2/pig) and fed diets based on corn, soybean meal, and dried distillers grains with solubles containing 60 mg/kg Zn (phases 1, 2, and 3), and 50 mg/kg Zn (phase 4); (2) crowded (Con11)—pigs housed at 0.60 m2/pig and fed the same diets as Con9; (3) ZnAA40—same as Con11 + 40 mg/kg Zn from Zn AA complex (Availa-Zn, Zinpro Corp., Eden Prairie, MN); (4) ZnAA80—same as Con11 + 80 mg/kg Zn from Zn AA complex; and (5) inorganic zinc (ZnSO80)—same as Con11 + 80 mg/kg Zn from zinc sulfate monohydrate. Growth characteristics were determined at the end of each dietary phase (28 d). Upon completion of the trial, carcass composition and meat quality were recorded. Overall, crowding decreased ADG (P

Tunable Magnetic and Electrical Properties of Cobalt and Zinc Ferrites CO1-XZnXFe2O4 Synthesized by Combustion Route

Co and Zn ferrites with general formula CO1-XZnXFe2O4 (x = 0; 0,2 and 0,8) were synthesized by combustion reaction method, using urea as fuel. The structure of inverse-spinel-type ferrite were characterized through XRD using Rietveld refinement method to identify, quantify phases and determine lattice parameters. The crystallites had mean size of 37,33 nm, 43,66 nm and 51.88 nm with the increment of Zn2+, respectively. Samples were sintered in a resistive oven at 900 °C for 3 hours. Analysis by SEM indicated that the particles have irregular sizes and high concentration of open pores. The magnetic properties were measured using a vibrating sample magnetometer (VSM), through which a decrease in the magnetization variation was observed as the non-magnetic Zn2+ concentration increases. The permittivity and loss tangent were determined using vector network analyzer equipment, permittivity increases with the increase of zinc concentration and the tangent loss measurements were small for all ferrites synthesized in this work.

The quality of root exudates and the effect of type and age of plant and soil in iron, zinc readiness in soil rhizophere and bulk soil.

The study was conducted in the plastic house of the Department of Soil Science and Water Resources, college of Agriculture and Forestry / University of Mosul. The study included two experiments:-
 The first experiment to study the quality of root exudates produced by plant roots using four type of plants, (wheat, onions, faba bean, clover) had been cultivated in the nutrient solution (Cooper) that contains all the nutrients needed for plants growth during different growth stages. Samples of the nutrient solution for each crop at different stages of development (60،100،150 days). were token. The results showed the presence of reducing sugars and cellulose , hemicellulose, sucrose and disaccharides weakly reduction (glucose, maltose) and Hexose sugar Aldosugar and Hexose sugar ( glucose, fructose) and organic acids at 150 days stage of growth.
 The second experiment was conducted to study the available iron and zinc Rhizosphere and Bulk Soil using the four types of crops which had been cultivated in silty clay loam soil from Al-​​Rashidiya site, Samples of the soil were took to estimated the nutrient concentration (Fe, Zn) in two phases of stages of plant growth (60 days, 120 days). The Results showed increase in Iron and Zinc concentration in the soil rhizosphere and the highest increase in the iron concentration was in the faba bean crop (3.48 mg .kg-1) at the first stage of growth had been noted. In second phase the highest concentration of the Iron was in the soil cultivated crop clover (3.33 mg .kg-1) compared with the control (2.05 mg . kg-1), The highest increasing in available Zinc was in the rhizosphere soil which cultivated with clover crop (0.62 mg. kg-1) at the first stage of growth as compared with the control (0.31 mg.kg-1) increase 100%.

Time Matters: the Toxicity of Zinc Oxide Nanoparticles to Lemna minor L. Increases with Exposure Time

The use of zinc oxide nanoparticles (nano-ZnO) has rapidly increased in recent years, and this has triggered the need for versatile toxicity tests that can be used to test a range of different exposure scenarios. Acute exposure studies, using a variety of plant species, have overwhelmingly demonstrated nano-ZnO-induced toxicity, but substantial differences in the degree of phytotoxicity are reported in different studies. Here, we analysed the role of exposure time in determining the variation in phytotoxic effects. Using the model species Lemna minor, the effects of short-term (24 h), standardised (1 week) and chronic (up to 6 weeks) nano-ZnO exposure were compared. Nano-ZnO effects on Lemna minor growth indicators (biomass growth rate, root length), chlorophyll content and photosynthetic efficiency were measured. Rapid inhibitory effects of nano-ZnO on the maximal quantum yield of photosystem II could be measured after just 24-h exposure. Standardised (1 week) experiments revealed phytotoxic effects on Lemna minor biomass growth. More severe inhibitory effects on growth developed gradually over 4 to 6 weeks exposure to nano-ZnO, and these were qualitatively associated with increased zinc content in the plant. Such dynamics of nano-ZnO toxicity have not been elucidated before, and this study emphasises the importance of exposure time in studies of nanoparticle toxicity. We conclude that short-term, standardised experiments can potentially underestimate the environmental phytotoxicity, which may result from chronic exposure to nano-ZnO.

Effects of Dietary Zinc Oxide Nanoparticles on Growth, Diarrhea, Mineral Deposition, Intestinal Morphology, and Barrier of Weaned Piglets.

This study was conducted to investigate effects of dietary zinc oxide nanoparticles (nano-ZnOs) on growth, diarrhea rate, mineral deposition (Zn, Fe, and Mn), intestinal morphology, and barrier of weaned piglets. A total of 384 weaned piglets (Duroc × Landrace × Yorkshire) in 4 groups were fed a basal diet supplemented with 0, 400, and 800mg/kg nano-ZnOs or 3000mg/kg ZnO for 14days. Compared with the control group, 800mg/kg nano-ZnOs and 3000mg/kg ZnO significantly increased average daily gain and decreased diarrhea rate of weaned piglets. There was no significant difference among ZnO and nano-ZnO groups. ZnO and nano-ZnOs did not affect serum activities of glutamic oxalacetic transaminase, glutamic-pyruvic transaminase, and lactate dehydrogenase. However, ZnO and 800mg/kg nano-ZnOs significantly increased zinc concentrations in plasma, liver, pancreas, and tibia, without affecting Fe and Mn concentrations. Compared with the control group, 800mg/kg nano-ZnOs significantly reduced plasma diamine oxidase activity, decreased total aerobic bacterial population in mesenteric lymph node, enhanced mRNA expressions of occludin, ZO-1, IL-1β, IL-10, TNF-α, and ki67 in ileal mucosa, and increased villous height, width, crypt depth, and surface area. Compared to ZnO group, 800mg/kg nano-ZnOs significantly decreased aerobic bacterial population, enhanced mRNA expressions of occludin, IL-1β, IL-10, and TNF-α, and reduced fecal zinc concentration. These results indicated that 800mg/kg nano-ZnOs might be a potential substitute for 3000mg/kg ZnO in diets of weaned piglets.

Imaging the penetration and distribution of zinc and zinc species after topical application of zinc pyrithione to human skin

Zinc pyrithione is an active component incorporated in an extensive range of topically applied commercial products that are used worldwide. Despite its prevalence, no published study has investigated the penetration of zinc from the zinc pyrithione complex into human skin. Zinc is crucial for healthy skin function however an elevated concentration of labile zinc is toxic outside a narrow concentration range. Synchrotron X-ray fluorescence microscopy in conjunction with X-ray absorption near edge structure spectroscopy was used to map the deposition of zinc, quantitate the amount of zinc within the skin and to identify a change in the chemical form of zinc after application. This study has demonstrated a ~3.8 fold increase in zinc concentration within the viable epidermis (VE) after 24 h topical application of zinc pyrithione that increased significantly by ~250 fold after 48 h when compared to control skin. Confocal microscopy using a labile zinc specific dye, ZinPyr-1, showed that zinc pyrithione disrupted the skin cells zinc homeostasis and significantly increased the intracellular zinc concentration leading to cell toxicity. Overall, this study demonstrates that topical application of zinc pyrithione formulations leads to an increase in zinc penetration in human skin, consequently, raising concerns for potential localised toxicity to occur.

Effect of hypotensive therapy combined with modified diet or zinc supplementation on biochemical parameters and mineral status in hypertensive patients

BackgroundHypotensive therapy leads to a number of trace elements metabolism disturbances. Zinc balance is frequently affected by antihypertensive treatment. AimTo evaluate the effect of a hypotensive treatment, modified diet and zinc supplementation on mineral status and selected biochemical parameters in newly diagnosed hypertensive patients on monotherapy. MethodsIn the first stage, arterial hypertension in ninety-eight human subjects was diagnosed. In the second stage, antihypertensive monopharmacotherapy was implemented. In the third stage, patients were randomized into three groups and continued antihypertensive monotherapy: group D received an optimal-mineral-content diet, group S received zinc supplementation, and group C had no changes in diet or zinc supplementation. Iron, zinc, and copper concentrations in serum, erythrocytes, urine, and hair were determined. Lipids, glucose, ceruloplasmin, ferritin, albumin, C-reactive protein (CRP), tumor necrosis factor α (TNF-α), nitric oxide (NO), superoxide dismutase (SOD) and catalase (CAT) were assayed in serum. ResultsAntihypertensive monotherapy decreased zinc concentration in serum and erythrocytes and increased the level of zinc in urine, decreased CAT and SOD activity, TNF-α concentration in serum, and increased the level of NO in the serum. Zinc supply led to an increase in zinc concentration in serum, erythrocytes, and hair (in group S only). In the groups with higher zinc intake, decreased glucose concentration in the serum was observed. Significant correlation was seen between the zinc and glucose serum concentrations. ConclusionHypotensive drugs disturb zinc status in newly diagnosed hypertensive patients. Antihypertensive monotherapy combined with increased zinc supply in the diet or supplementation favorably modify zinc homeostasis and regulate glucose status without blood pressure affecting in patients with hypertension.

Effect of zinc on the collagen degradation in acid-etched dentin

Background/purposeMatrix metalloproteinases (MMPs) play a crucial role in the pathogenesis of dental caries, collapse of adhesive interface, and chemical erosion of teeth. The objective of this study was to investigate the inhibitory effect of zinc on collagen degradation. Materials and methodsHuman dentin was ground and demineralized by citric acid (pH 2.0). The demineralized ground dentin was incubated in six different media: artificial saliva (AS); 5 mg/ml doxycycline in AS; 3.33, 6.82, 13.63, and 27.26 mg/ml of zinc chloride (Zn) in AS. Each group was divided into two subgroups, and active MMP-2 was incorporated into one subgroup. Specimens were incubated for 24 h, 1 week, and 2 weeks. Collagen degradation product was assessed using ELISA. The results were analyzed using repeated measured ANOVA and Duncan's post hoc analysis (α = 0.05). ResultsThe amount of collagen degradation was the lowest in Doxy group. Zn groups showed a significant inhibitory effect in collagen degradation for all concentrations (P < 0.05). In subgroups without exogenous MMP-2, zinc-mediated inhibition increased in a concentration-dependent manner with increasing zinc concentration. The amount of collagen degradation product slightly increased with increased incubation time from 24 h to 2 weeks. However, in subgroups with exogenous MMP, the inhibitory effect of zinc on collagen degradation did not depend on zinc concentration. ConclusionAll Zn groups for the four concentrations tested exhibited statistically significant inhibitory effect on collagen degradation.

Changes in the zinc content of selected bangladeshi rice varieties through modified parboiling and milling methods

Zinc deficiency is prevalent among women and children in Bangladesh, and methods to increase the zinc content of parboiled rice could contribute to its prevention. We quantified the effect of modified parboiling conditions on zinc content and of the degree of milling on zinc and phytate contents of Bangladeshi rice varieties. Parboiling studies varied the conditions used in the local commercial operations, including pre-steaming and soaking times, change of soaking water, and steaming pressure. Milling studies used 10 Bangladeshi varieties at 0% (brown), 2%, 4%, 6%, 8%, and 10% degree of milling. With ambient soaking water, shorter soaking time was observed with a higher zinc content in brown rice, but not in 10% milled rice, and changing soaking water did not modify zinc content in brown or 10% milled rice. Pre-steaming time and open- vs. closed-system steaming had no significant effect on brown or 10% milled rice zinc content. Reducing the degree of milling from 10% to 6% or 4% resulted in a mean increase in zinc content of 27% and 47%, respectively, and an increase in phytate content of 35% and 72%, respectively. Zinc content in milled rice did not appear to be significantly affected by the parboiling conditions tested. While lower degree of milling resulted in higher zinc content, it is uncertain whether the higher phytate content would fully negate this increase by decreasing the bioavailable fraction of zinc. Human studies of zinc bioavailability from Bangladeshi rice at different degrees of milling are warranted.SAARC J. Agri., 15(2): 31-43 (2017)

Study of amorphous Zinc Germanium Nitride thin films grown by reactive co-sputtering

Under its crystalline form, the ZnGeN2 alloy is promising for optoelectronic devices such as LEDs because of its large, direct and adjustable band gap. Nevertheless, data are scarce, more especially for the amorphous form. We report here on the study of zinc germanium nitride amorphous thin films obtained by reactive co-sputtering. The samples are elaborated by PVD and analyzed by physical and chemical methods to determine their composition, structure and optical properties. We observe a clear evolution of these properties with composition. The shape of the complex refractive index reveals changes in the electronic structure. Furthermore, the optical gap and Urbach energy decrease with increasing zinc content.

Synthesis of Zn x Co3−x O4 spinels at low temperature and atmospheric pressure

In order to synthesize cobalt-based spinel oxides, air was bubbled through aqueous hydroxides suspensions of cobalt and zinc with atomic ratios of Co:Zn = 100:0, 85:15, 67:33 (precisely 2:1), 50:50, 30:70, 15:85, and 0:100 at 70 °C and atmospheric pressure. When cobalt was absent in the suspensions, hexagonal ZnO nanocrystals with ca. 82.2 nm size were observed, whereas cubic Co3O4 ones with ca. 52.7 nm were seen when zinc was not present. Zinc-contained cobalt spinel oxides, i.e., Zn x Co3−x O4 (x = 0–1), were obtained when both hydroxides were present, e.g., spherical nanoparticles with ca. 107.6 and 85.0 nm diameters were observed for Co:Zn = 50:50 and 67:33, respectively. The lattice constant, a, for the cubic spinel increased with the increase in zinc atomic %, suggesting the increase in zinc concentration in the spinel. The Zn x Co3−x O4 synthesized was normal spinel with a cubic crystal structure, whereas it was also suggested that a very small portion of zinc ion was incorporated into the octahedrally coordinated sites (inversion of spinel). BET surface area of the synthesized catalyst increased with increasing the cobalt atomic % except for Co:Zn = 67:33, for which local minimal surface area was obtained. Oxygen storage capacity of the catalyst was the largest for Co:Zn = 85:15 at 150 and 200 °C, whereas it was for 50:50 at 250 °C. After reducing the synthesized catalysts with hydrogen, metallic cobalt was formed on zinc oxide. CO chemisorption number on the cobalt was the largest for Co:Zn = 67:33, for which the smallest metallic cobalt diameter was also obtained. On the other hand, catalytic CO2 hydrogenation activity and methane selectivity were the highest for Co:Zn = 50:50, suggesting that zinc oxide as a basic support played an important role in the hydrogenation of acidic CO2. It was also shown that the catalytic hydrogenation activity and the methane selectivity were higher for the catalysts prepared by the present liquid-phase approach than for those prepared by conventional coprecipitation and impregnation methods, which were ascribed to larger surface area and number of active sites for the former preparation technique than for the latter two.

Magnetic heating of triethylene glycol (TREG)-coated zinc-doped nickel ferrite nanoparticles

Triethylene glycol (TREG)-coated nickel-zinc (Ni-Zn) ferrite nanoparticles were synthesized via the hydrothermal method and characterized for application to magnetic hyperthermia. Ni-Zn ferrite particles of Ni1−xZnxFe2O4 with three different zinc contents of x=0.2, 0.4, and 0.6 were formulated to investigate the structural and magnetic properties according to the zinc content. Transmission electron microscopy images revealed that the particles were spherical in shape and that the average diameters of the particles were 10.67, 13.02, and 18.73nm for zinc contents of 0.6, 0.4, and 0.2, respectively. Fourier transform infrared spectroscopy confirmed that the TREG was firmly coated on the surface of the particles. The saturation magnetization decreased with the increasing zinc content in the particles, which affected the heating ability of the particles in the alternating magnetic field. The heating ability of the Ni0.8Zn0.2Fe2O4 and Ni0.6Zn0.4Fe2O4 particles facilitated the aqueous solution of these particles to reach the target temperature of 42°C for magnetic hyperthermia, while an aqueous solution of Ni0.2Zn0.8Fe2O4 particles with a high particle concentration did not reach the target temperature. The high specific absorption rates of the Ni0.8Zn0.2Fe2O4 and Ni0.6Zn0.4Fe2O4 particles indicate that these particles are applicable to magnetic hyperthermia.

Quantifiable effects of regular exercise on zinc status in a healthy population-A systematic review.

Zinc is an essential mineral of which its functions have potential implications on exercise performance and beneficial adaptations of physical activity. While the effects of aerobic exercise on zinc metabolism acutely have been well described, the effect of long-term exercise training on zinc status remains unclear. The present review aims to determine the effects of exercise training on markers of zinc status in an apparently healthy adult population. We conducted a systematic literature search on PubMed, Scopus, SPORTDiscus and Cochrane Library from inception to 28 January 2016 to identify interventional or cohort studies that investigated the effects of exercise training on indices of zinc status. Pairwise comparisons of mean differences in within-group change were calculated and summarised visually in forest plots. Six studies satisfied the inclusion criteria for the systematic review, of which 5 studies included data on changes in serum zinc concentrations and 3 studies provided changes in dietary zinc intake. Two comparisons showed significantly higher increase of serum zinc concentrations in the exercise group compared to control, while one comparison reported significantly lower change in serum zinc for the exercising group. The exercise groups consumed significantly higher dietary zinc compared to controls in two comparisons. The present review revealed an incomplete evidence base in evaluating the effect of long-term exercise training on markers of zinc status. Further well-designed investigations are required to elucidate the relationship for establishment of dietary recommendation in populations who are continuing exercise interventions.

Chronic dietary toxicity of zinc oxide nanoparticles in common carp (Cyprinus carpio L.): Tissue accumulation and physiological responses

Concerns regarding the potential toxic effects of zinc oxide nanoparticles (ZnO NPs) on aquatic organisms are growing due to the fact that NPs may be released into aquatic ecosystems. This study aimed to investigate the effects of dietary exposure to ZnO NPs on juvenile common carp (Cyprinus carpio). Fish were fed a spiked diets at doses 50 and 500mg of ZnO NPs per kg of feed for 6 weeks followed by a 2-week recovery period. Fish were sampled every 2 weeks for haematology trends, blood biochemistry measures, histology analyses, and determination of the accumulation of zinc in tissues. At the end of the exposure and post-exposure periods, fish were sampled for an assessment of lipid peroxidation levels. Dietborne ZnO NPs had no effects on haematology, blood biochemistry, and lipid peroxidation levels during the exposure period. After the recovery period, aspartate aminotransferase activity significantly (p < 0.05) increased and alanine transferase activity significantly (p < 0.05) decreased in the higher exposure group. The level of lipid peroxidation significantly (p < 0.05) decreased in liver of treated fish after 2 weeks post-exposure period. A histological examination revealed mild histopathological changes in kidneys during exposure. Our results did not show a significant increase of zinc content at the end of experiment in any of tested organs. However, chronic dietary exposure to ZnO NPs might affect kidney and liver function.

Hot-tearing susceptibility of Al–Zn alloys

The modern concepts of the causes of hot tearing are considered and the influence of the solid fraction growth rate of an alloy is studied. The hot-tearing susceptibility (HTS) of binary Al–(5–73) wt % Zn alloys is investigated using backbone tests. The HTS is found to be maximal at ~25 wt % Zn. This maximum cannot be explained by a change in the effective solidification range, since this range of the alloys decreases monotonically with increasing zinc content. The calculations of nonequilibrium solidification by the Scheil–Gulliver model and the solid fraction growth rate of the alloys under study demonstrate that the increase in the HTS induced by an increase in the zinc content from 5 to 25 wt % is related to the decrease in the solid fraction growth rate at the final stages of solidification. The decrease in the HTS at >25 wt % Zn is associated with an increase in the fraction of eutectic in the alloys (the solid fraction growth rate during the eutectic reaction tends toward infinity) and with a change in its morphology.

Effect of various nitrogen doses on copper and zinc accumulation in yellow lupine biomass

Abstract Field experiments determined copper and zinc content and accumulation in yellow lupine roots, stems, leaves, flowers, pods and seeds. The test factors included development stages (BBCH 65 and BBCH 90) at which harvest was performed as well as nitrogen doses (0, 30, and 120 kg·ha−1) introduced to the soil prior to sowing. A higher copper content (by an average of 20.9%) and zinc content (by 53.7%) were obtained in the whole mass of lupine harvested at the flowering stage compared to that at the full maturity stage. Yellow lupine fertilised with 120 kg N·ha−1 contained and took up more copper and zinc than both lupine cultivated without nitrogen fertilization and fertilised with 30 kg N·ha−1. The application of different nitrogen doses had no significant effect on the contents of the micronutrients in the seeds of the test plant. The amount of copper and zinc accumulated in the seeds was the largest following the application of 120 kg N·ha−1. Lupine accumulated the largest amounts of both elements in the leaves irrespective of the development stage at which the harvest was carried out. The bioaccumulation factor for copper and zinc was higher in the lupine harvested at the flowering stage than in the lupine harvested at full maturity, but it was not significantly determined by the applied nitrogen fertilization. The values of translocation coefficient for the tested heavy metals, usually higher than 1, indicate significant potential for their accumulation in yellow lupine biomass. Under conditions of an increased zinc content in the soil, lupine green matter harvested at the flowering stage contained an above-standard amount of this heavy metal and could not be used for animal feed.

HUBUNGAN KADAR TARTRAZIN DAN SENG (ZN) DALAM DARAH PADA ANAK PENDERITA DEFISIT PERHATIAN DAN GANGGUAN HIPERAKTIVITAS (ADHD)

This research aims to study Tartrazine and Zinc (Zn) status in blood sample of Attention Deficit Hyperactivity Disorder (ADHD) children. Deductive research using the descriptive method through 3 stage, namely : 1. Taken of blood sample, 2. Analysis of Tartrazine status in blood sample was performed by using High Performance Liquid Chromatograpy (HPLC) method, and 3. Analysis of Zinc (Zn) status in blood sample were measurements by using Atomic Adsorbance Spectrophotometry (AAS) method. Data were analyzed using descriptive analysis techniques and Chi Square tests (X2) by Computer programs (SPSS 15). The result of the assessment of Tartrazine status in blood sample of ADHD children that had been was considered statistically highly significant a increase of the assessment of Tartrazine status in blood sample of ADHD children by 130 mg/ml compared with laboratory reference (control) by 28 mg/ml, HA&gt;C** (p&lt;0,001). The result of the assessment of Zinc (Zn) status in blood sample of ADHD children that had been was showed statistically highly significant a reduce of the assessment of Zinc (Zn) status in blood sample of ADHD children by 0,37 µg/ml compared with laboratory reference (control) by 0,64-1,18 µg/ml, HA&lt;C** (p&lt;0,001). This was considered a reduction and increase in Tartrazine and Zinc (Zn) concentrations induces of the Hyperactivity children by 95%.

Indirect determination of zinc by thiol complexation and iodine coulometric titration with photocell detection

We have extended the capabilities of iodine coulometry for the determination of ionic zinc through its complexation with cysteine and subsequent titration of the thiol. The titration endpoint times of cysteine with zinc are proportionally longer as compared to cysteine itself. A homebuilt constant-current coulometer is employed for this method development. The instrument is composed of a constant-current source connected to nonisolated platinum electrodes contained in a 150-mL beaker (the coulometric cell) that sits on a photocell mounted in a styrofoam lid on top of a magnetic stirrer. Photometric endpoint detection is facilitated by connecting the photocell detector to an operational amplifier circuit; its output, recorded on a multifunctional chemical analysis system, resembled a sigmoidal curve. The titration conditions are optimized in terms of pH, temperature, stirring rate, and cysteine-to-zinc concentration ratios. Calibration curves generated as time versus increasing zinc concentrations in the presence of a constant cysteine concentration are used to determine zinc content in dietary supplements. The limit of detection is 5.5×10−5M Zn and the limit of quantification is 6.2×10−5M Zn. Percent relative standard deviations are at 4%. The recoveries of zinc from liquid zinc, enhanced zinc lozenges, and zinc tablets generally range from 80 to 120%. Titration of ascorbic acid and then zinc in the same solution is successfully performed with recoveries greater than 95% for both analytes. A comparison of the coulometry Zn data to atomic absorption results is also made for most samples.

Structure and optical properties of LiNbO3:ZnO (3.43–5.84 mol %) crystals

LiNbO3:ZnO (3.43–5.84 mol %) crystals have been studied using Raman spectroscopy and fullprofile analysis of X-ray diffraction data. The results demonstrate that, at ZnO concentrations above 3.95 mol %, their structure is free of NbLi basic defects, which are characteristic of congruent lithium niobate crystals. Increasing the Zn concentration leads to changes in the arrangement of structural units in the cation sublattice along the polar axis and distorts the BO6 (B = Nb, Li, Zn, or a vacancy) oxygen octahedra. In the Raman spectra of the crystals, the width of the line at a frequency of 876 cm–1, which corresponds to stretching modes of the oxygens in the BO6 octahedra, has been shown to increase considerably, which may be due to changes in the character of bonding in the B–O–B bridges in response to changes in the Zn concentration in the crystals. The gradual increase in the electro-optical coefficients of the LiNbO3:ZnO crystals with increasing zinc concentration can be accounted for by changes in the ionic contribution to these bonds.