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Aqueous copper(II) photoinduced polymerization of acrylates : low copper concentration and the importance of sodium halide salts

Aqueous copper(II) photoinduced polymerization of acrylates : low copper concentration and the importance of sodium halide salts

Photoinduced metal mediated radical polymerization is a rapidly developing technique which allows for the synthesis of macromolecules with defined molecular weight and narrow molecular weight distributions, although typically exhibiting significant limitations in aqueous media. Herein we demonstrate that the presence of alkali metal halide salts in conjunction with low copper concentration and UV irradiation, allows for the controlled polymerization of water soluble acrylates in aqueous media, yielding narrow molecular weight distributions and high conversions. Despite the aqueous environment which typically compromises polymer end group fidelity, chain extensions have also been successfully performed and different degrees of polymerization were targeted. Importantly, no conversion was observed in the absence of UV light and the polymerization could be switched “on” and “off” upon demand as demonstrated by intermittent light and dark periods and thus allowing access to spatiotemporal control.
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EFFECT OF COPPER CONCENTRATION ON  THE GROWTH OF  METHYLOCOCCUS CAPSULATUS (STRAIN М)

EFFECT OF COPPER CONCENTRATION ON THE GROWTH OF METHYLOCOCCUS CAPSULATUS (STRAIN М)

At the copper concentration that favours fastest specific growth rate of the studied culture and those below it (≤ 40 μМ) no structural changes in M. capsulatus (М) cells are observed (Figure 2а). Cells are cocci (within 1 μm) and diplococci. Prevalence of the latter is observed in cultures growing in conditions close to optimal, whereas the former, having dark cytoplasm (as displayed by phase contrast microscopy) dominate (up to 95%) under nonsterile conditions. A well-developed network of internal cytoplasmic membranes with localized pMMO is present. At copper concentrations 1.5 times higher than optimal, electron-dense intracellular inclusions are found, which are nonmetabolized copper spread throughout cytoplasm in nanoscale granules (Figure 2b). Metal ions entering the bacteria cell cytoplasm can be complexed by inorganic anions. It is possible, that copper is accumulated in sulphides, as it happens in Mycobacterium scrofulaceum cells [18]. After further increase in copper concentration in the medium (up to 100 μМ), electronic microphotographs show copper sorption on the cell wall with copper at the same time being present in cells cytoplasm (Figure 2c). Copper adsorption on the surface of M. capsulatus (М) occurs by binding with the cell wall and cytoplasmic membrane. Changes taking place in M. capsulatus (М) cells at elevated copper concentrations (≥100 µM) are mostly concerned with the cells morphology. During M. capsulatus (М) cultivation, an increase in cell size is observed (Figure 2c), which is concerned with the suppression of cell division. M. capsulatus (М) metal-resistance is provided by sorption and intracellular copper accumulation through complexation with microorganisms’ biomass. Accumulation of Cu(II) in the periplasmic space and outer membrane was, also, observed in bacteria Pseudomonas syringae [19].
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Influence of electron donors and copper concentration on geochemical and mineralogical processes under conditions of biological sulphate reduction

Influence of electron donors and copper concentration on geochemical and mineralogical processes under conditions of biological sulphate reduction

Sulphidogenous microorganism communities were isolated from soil polluted by crude oil. The study was focused on determining the influence of 1) copper (II) concentration on the activity of selected microorganism communi- ties and 2) the applied electron donor on the course and evolution of mineral-forming processes under conditions favouring growth of sulphate-reducing bacteria (SRB). The influence of copper concentration on the activity of se- lected microorganism communities and the type of mineral phases formed was determined during experiments in which copper (II) chloride at concentrations of 0.1, 0.2, 0.5 and 0.7 g/L was added to SRB cultures. The experi- ments were performed in two variants: with ethanol (4 g/L) or lactate (4 g/L) as the sole carbon source. In order to determine the taxonomic composition of the selected microorganism communities, the 16S rRNA method was used. Results of this analysis confirmed the presence of Desulfovibrio, Desulfohalobium, Desulfotalea, Thermotoga, Solibacter, Gramella, Anaeromyxobacter and Myxococcus sp. in the stationary cultures. The post-culture sediments contained covelline (CuS) and digenite (Cu 9 S 5 ). Based on the results, it can be stated that the type of carbon source applied during incubation plays a crucial role in determining the mineral composition of the post-culture sediments. Thus, regardless of the amount of copper ion introduced to a culture with lactate as the sole carbon source, no cop- per sulphide was observed in the post-culture sediments. Cultures with ethanol as the sole carbon source, on the other hand, yielded covelline or digenite in all post-culture sediments.
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Seasonal variations of serum copper concentration in Raeini cashmere goats

Seasonal variations of serum copper concentration in Raeini cashmere goats

The concentration of Cu in forage was higher in au- tumn than summer. In autumn, the concentration of Cu was adequate for goats, but found to be borderline to deficient during summer. The concentration of Cu in plant species was less than the critical range needed by the animal; in other words, deficiency of Cu content in the feed was found in both dry and wet seasons. Warly et al. (2006) reported that the concentrations of micro- minerals as Cu in forage were significantly affected by species and season. Lundu (2012) reported that the Cu concentration in plasma, plant material, and soil was af- fected by season.
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Is a high serum copper concentration a risk factor for implantation failure?

Is a high serum copper concentration a risk factor for implantation failure?

Komai [15] previously reported that taste distur- bances caused by a zinc deficiency were more common in Japan than in Western countries. The reason Japanese women had low zinc (high copper) concentrations may be partly explained by their eating habits; they may eat more soybeans and processed foods than meat. Meat is one of the best sources of zinc, soybeans contain phytic acid, a natural zinc-chelating agent, and processed foods contain many food additives, which function as zinc- chelating agents (c.f., EDTA, polyphosphoric acid, and carboxymethyl cellulose) [26]. Recent national food bal- ance data obtained from 176 countries indicated that approximately 20.5% of the world’s population (33.1% in Southeast Asia) is estimated to be at risk of an inadequate zinc intake [27]. Thus, we recommend all women who do not have Wilson’s disease and those who have not used copper-containing contraceptive devices to pay more attention to their food and eating habits (i.e., more meat, less soybeans, and less processed foods), which may be altered.
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A Survey of the Effect of Some Heavy Metals in Plant on the Composition Of The Essential Oils Close to Veshnaveh-Qom Mining Area

A Survey of the Effect of Some Heavy Metals in Plant on the Composition Of The Essential Oils Close to Veshnaveh-Qom Mining Area

Copper concentration should be low in plants. Due to the Redox feature of copper, its high concentration is dangerous. The mean content of copper in plant tissue is 10 microgram/gram. Excess copper avoids plant growth and is involved in important cellular processes as photosynthesis and respiration. The plants growing in high copper concentration show reduction in biomass and chloratic signs. Low chlorophyll content and changes of chloroplast structure and composition of thylakoid membrane in leaf are found under such growth conditions, namely destruction of grana lamellae and stroma lamellae and the increase of size and number of plastoglobuli are observed. Based on the adverse effects of copper and its important role, copper reduction, as in the structure of the identified compound in essence there is carbon-carbon double bond and carbon-oxygen double bond, copper reduces these bonds and changes their structure.
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Study on the production and species specificity of methanobactin

Study on the production and species specificity of methanobactin

(hexadecyltrimethylammonium). This gives a final copper concentration of 0.5 mM, a CAS concentration of 1mM and a HDTMA concentration of 2mM. The resultant dark blue liquid was autoclaved. Also autoclaved was 450 ml of mineral salt agar. Concentrations of salts were adjusted for 500 ml mineral salt medium, considering later addition of the Cu–CAS solution. After cooling to ~50°C, 50 ml of Cu–CAS solution was carefully added into mineral salt agar medium along the glass wall, with enough agitation to achieve mixing. After the agar plates cooled and solidified, half of the agar gel was carefully excised with a sterilized razor. The empty space was then filled with sterilized mineral salt agar with 1 µM copper. Methanotrophs were streaked onto mineral salt agar with 1 µM copper immediately adjacent to 50 µM Cu–CAS agar; a color change in modified CAS plate was observed as copper ion weakly bound to CAS is taken up by Mb.
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Removal of Trace Amounts of Copper from Concentrated Hydrochloric Acid Solutions

Removal of Trace Amounts of Copper from Concentrated Hydrochloric Acid Solutions

Pickling process is recognized as one of the strongest acid consuming processes in the steel industry. A pickling solution that contains hydrochloric acid (HCl) is used for the metal surface treatment of steel plants. The same acid can be used for a long period of time by means of a regeneration process, in which iron concentration of the acid is decreased to insignificant concentrations. However, regenerated pickling solutions contain copper, especially when scrap is used to produce steel. Furthermore, copper deposits on the metal in the following pickling processes when its concentration exceeds a certain critical value. This study describes an electrochemical treatment process for collecting copper from regenerated pickling solutions of steel plants. Copper concentration, electrolysis time, and current density were selected as the operation variables and pH and conductivity of the acid together with the amount and morphology of the deposition were considered as the response variables for optimization. Graphite was used as the anode due to its high conductivity and stability and copper or stainless steel was used as the cathode in this study. The results showed that electrochemical treatment process decreased copper concentration to about 80 from 127 ppm using stainless steel cathode under the optimum constant current density of 2.0 A/dm 2 and electrolysis time of 4 hours, without any acid loss, which was verified by pH, conductivity and acidity measurements.
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Application of copper-based ovitraps in local houses in West Sumatra, Indonesia: a field test of a simple and affordable larvicide for mosquito control

Application of copper-based ovitraps in local houses in West Sumatra, Indonesia: a field test of a simple and affordable larvicide for mosquito control

in copper-treated containers. Mortality rates reached 98.3 % in copper-treated pots. In the control pots, all larvae were healthy and active. No dead larvae were found. It may be because the surviving larvae ate dead larvae under the conditions of lacking food. Thus, the survival rate in the control pots (100 %) might be overestimated. However, the lethal effect of the copper is evident as no larvae survived in most of the copper pots. Several surviving larvae were detected in two copper- treated pots outside one house (house no. 7). The house was located near a swamp close to the sea, and the two containers were laid outside a semi-closed bathroom, which allowed rain to dilute the concentration of copper in these pots. We suspect that dilution occurred several days before day 14, because a large number of dead larvae were simultaneously detected with surviving lar- vae. However, the surviving larvae were small and weak with limited movement. We conclude that although these larvae survived the residual copper concentration, they were still exposed to the damaging effects of copper on their health and development.
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EDTA enhanced transport of copper from contaminated soil and its implications : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University

EDTA enhanced transport of copper from contaminated soil and its implications : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University

The off-site washing method of remediation is not practically or economically feasible for large areas of agricultural land, and hence in situ methods need to be considered. One of the crucial factors for the success of any phytoremediation technology is the time required for eventual site decontamination. The time requirements for clean-up of the Opotiki soil investigated in this study can be roughly estimated as follows. The maximum copper concentration measured in the A tenuis grown on the Opotiki repacked soi1 was 300 mg kg-I (0.3 kg (1) and the dry matter production was 4.2 t h-I . If similar behavior were to occur under the field conditions a crop of A tenuis grown over a hectare of Opotiki soil might be expected to remove 1 .3 kg h-I of copper in a single harvest each year. Copper contamination in the Opotiki soil was mostly found in the surface 8 cm. If the top 8 cm of soil is considered for remediation, assuming a bulk density of 1 100 kg m-3, the weight of the soil is 8.8 x 1 05 kg per hectare. The copper concentration varied with depth and space, however assuming a 400 mg kg-I of concentration was assumed throughout the 8 cm depth, the time required for a four fold reduction to 100 mg kg-1 in copper concentration would be 209 years. If two harvests were possible in a year, then the same reduction in copper concentration could be achieved in 104 years. Based solely on the long time requirement calculated, the prospects for using in situ application of EDTA to enhance phytoremediation of copper do not seem good with Atenuis.
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Copper Metabolism of Newborns Is Adapted to Milk Ceruloplasmin As a Nutritive Source of Copper

Copper Metabolism of Newborns Is Adapted to Milk Ceruloplasmin As a Nutritive Source of Copper

it was shown that intracellular and local extracellular changes in copper concentration influence the.. 103.[r]

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Preparation of Chitosan Copper Complexes: Molecular Dynamic Studies of Chitosan and Chitosan Copper Complexes

Preparation of Chitosan Copper Complexes: Molecular Dynamic Studies of Chitosan and Chitosan Copper Complexes

This work studied the effect of copper ions concentration chelated by functional groups in chito- san on its molecular dynamic. Chitosan Copper complexes prepared having different copper con- centrations by the electrochemical oxidation technique in aqueous-acetic acid medium. It was car- ried out at constant voltage (2 volt.) at room temperature at different electro-oxidation time. The result of partial elemental analysis and XRD studies of chitosan copper complexes compared with chitosan confirmed that the percentage composition of the complexes were found to be depend on the time of electrolysis which is in good agreement with our previous work. Interpretation of the effect of copper ions concentration on molecular motion of chitosan studied using dielectric spec- troscopy, the results showed that dielectric constant of chitosan is higher than that of chitosan copper complexes. This may be attributed to the relatively fast segmental motion of chitosan chain slowed down by complexation with copper ions of all complex samples. Calculated activation energy from Arrhenius variation showed increase in value with increasing the copper concentration and all in the range that required for ionic conduction. Temperature dependence part of dielectric parame- ters gives very useful representation in the glass transition temperature determination.
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Ceruloplasmin and superoxide dismutase (SOD1) in heterozygotes for Wilson disease: A case control study

Ceruloplasmin and superoxide dismutase (SOD1) in heterozygotes for Wilson disease: A case control study

Ceruloplasmin concentration, oxidative activity and specifi c oxidative activity were normally distributed in the controls. The GGT activity and copper concentration did not pass normality tests (D’Augostino and Pearson omnibus and Shapiro–Wilk), but did so after the transformation to loga- rithmic fi gures. The SOD1 activity did not pass the normality tests, and transformation of the SOD1 values to logarithmic fi gures did not change this. For this reason, SOD1 activity in heterozygotes and the age- and gender-matched controls were compared by using Wilcoxon’s two-sample test. The student’s two-way t-test was used for comparing the results of the logarithmic fi gures of GGT and copper and for the determinations of CP concentration, oxidative activity and
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Evaluation of Tropical Legume Cover Crops for Copper Use Efficiency

Evaluation of Tropical Legume Cover Crops for Copper Use Efficiency

Concentration (content per unit dry weight) of copper was significantly affected by soil applied copper rates, cover crop species and their interactions (Table 6). The significant interaction between soil copper X cover spe- cies indicates that Cu concentration in the crop species varied with the change by soil applied Cu rates. Across four soil applied Cu rates, the copper concentration in the shoots of cover crop species varied from 2.24 mg kg −1 to 8.20 mg kg −1 , with an average value of 5.38 mg kg −1 . The variation in Cu content among cover crop species was due to variation in dry weight. The Cu concentration in the shoot of Jack bean was the lowest although Jack bean had the maximum dry weight. Conversely, tropical kudzu had the highest Cu concentration but the mini- mum dry weight. The concentration of a nutrient related to dry weight is known as dilution effect in the field of mineral nutrition [2]. Higher dry matter yield means more dilution effect or lower nutrient concentration and vice versa. Overall, Cu concentration decreased in a quadratic fashion with increasing soil applied Cu rates
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Features of The Electrolytic Copper Powder Deposition in the Presence of Polyols

Features of The Electrolytic Copper Powder Deposition in the Presence of Polyols

Injection of glycerin to the solution in an amount of 10 ml/l with copper concentration of 5 g/l and sulfuric acid of 10 g/l, leads to a significant change in the form of the polarization curve in comparison with the curve without glycerol. In particular, the injection of glycerin leads to a slight shift of peak potential in positive direction, and at the same time to a fall-off of the current peak value. Lowering of the current peak probably is related, as noted above, with a significant increase in viscosity. Shift of the peak potential is caused by the same process of viscosity change, because reducing current limit leads to earlier formation of the maximum rate of non-steady state process. Under these conditions, the formation of the maximum copper is determined by two components: the rate of copper ions supply and their electrochemical reduction.
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Evaluation of Heavy Metals in Platinum Tailing Dam Site

Evaluation of Heavy Metals in Platinum Tailing Dam Site

Similarly to the concentration of chromium ,the copper concentration was higher at 1 metre as compared to both 2 metre and 3 metre.1metre is a point closer to the dam and as the distance increases the concentration decreases at the furthest point from the dam this could be attributed to the fact that the nearer the sampling point is to the source of contamination (the dam), the higher the concentration of contaminant in the soil and in terms of varying depth the highest concentration is limited to the upper 0 cm depth. Previous studies have shown that when soluble Cu is added to soil it reacts with phosphates, clays and organic matter, which reduces its solubility considerably and results in greater retention of copper in the soil. The results also show that Cu is abundant in the topsoil and is least concentrated in the 30 cm layer. Butkus and Grasso [6] explained this in terms of drying, which hinders Cu mobility and because the topsoil is dryer than the subsoil, the copper is concentrated in the top layer of the soil.
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Gray Water Impacts & Utilization For Agriculture Commodities-Great Threat For Deliberation

Gray Water Impacts & Utilization For Agriculture Commodities-Great Threat For Deliberation

Creation of enabling environment for the citizens of any city is an alarming issue for custodians of the city concerned in the world. Quetta city is declared one of the worst polluted cities. Keeping in mind the causes of certain pollution in Quetta, a research study was conducted to find out the Pivotal factors of the said pollution. Results augmented that pH of the city wastewater was not ideal started from 7.610 in Killi Nohsaar up-to 7.820 in Killi Sabzal. Iron (Fe) contamination is very high and it was ranged from 0.213 ppm up-to 0.202 ppm which could cause Homosiderosis. Manganese determination in the city wastewater was 0.061 ppm up-to 0.048 ppm. The higher concentration of manganese could cause adverse effect on central nervous system. Copper concentration in city wastewater was ranged from 0.082 ppm up-to 0.061 ppm 0.061. Zinc accumulation ranged from 0.131 ppm up-to 0.120 ppm. Calcium concentration 120.000 ppm were found in the samples collected from sirki road followed by 116.000 ppm from Killi Nohsaar and110.000 ppm from Killi sabzal. As in spring water the calcium concentration is 19.9 mg/L. So, the higher concentration of calcium depresses cardiac activity and leads to respiratory and cardiac failure. Consuming more than 2500 mg of calcium per day might lead to kidney stones and problems with soft tissues. It is found that in Quetta city several people suffered from kidney problems. Maximum 18.000 ppm magnesium level was present in city wastewater collected form Killi sabzal. Consumption of excessive Magnesium-Mg may result in diarrhea, impaired kidney function, low blood pressure and muscle weakness. Higher sulphate concentration was noticed 127.219 ppm collected from sirki Road area, followed by 125.491 ppm from Killi Nohsaar. Maximum 117.006 ppm chloride was recorded in from Killi Nohsaar, followed by 115.375 ppm from Killi sabzal. Similarly, the highest 26.023 ppm nitrate was present in the samples collected from Killi Nohsaar; Followed by 25.670 ppm from Killi sabzal area and the lowest nitrate 23.987 ppm from sirki Road. As in normal water or spring water, the concentration of sulphate is 36 mg/L, chloride 16 mg/L and nitrate 0.68 mg/L respectively. But in the city wastewater the concentration of all these three elements were very high. Maximum iron 7.210 mg/100g was recorded in the samples of Spanich collected from Killi Nohsaar area, followed by 7.125 mg/100g from Killi sabzal area. Whereas the minimum 6.324 mg/100g of iron was recorded in the samples collected from Sirki Road area. The international standard of Iron in spinach (Spinacia Oleracea) is 2.71mg/100g. High concentration of iron could cause cirrhosis of liver and heart failure. Excessive intake of iron can cause cancer. Copper concentration in the samples collected ranged from 5.310 mg/100g up-to 5.013 mg/100g. If Copper to be taken in excessive quantity, would cause abdominal pain, nausea, diarrhea and
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Potentiometric Sensor for Trace Level Analysis of Copper Based on Carbon Paste Electrode Modified With Multi-walled Carbon Nanotubes

Potentiometric Sensor for Trace Level Analysis of Copper Based on Carbon Paste Electrode Modified With Multi-walled Carbon Nanotubes

AAS or flame atomic absorption spectrometry–electrothermal atomization (AAS-ETA) [6-8], inductively coupled plasma-optical emission spectroscopy (ICP-OES) [9, 10], anodic stripping voltammetry [11-13], chromatography [14, 15], gravimetric detection [16] or photometry [17] are used for its determination at low concentration level. Moreover, all these methodologies require a complex and expensive apparatus and this hinders their use for routine in Clinical Chemistry laboratories. [18] It is well known that the toxicity of this metal is attributed to “free cupric ion” rather than inorganic and organic complexes. [19] Potentiometric measurement with a copper selective electrode allows directly determination of free copper ion concentration in water samples. [20, 21]
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Adsorption of copper, cadmium and silver from aqueous solutions onto natural carbonaceous materials

Adsorption of copper, cadmium and silver from aqueous solutions onto natural carbonaceous materials

of silver onto wood and bark are of the linear-type. With linear isotherm it is impossible to determine the maximal uptake (adsorption capacity). The high- est adsorption capacities of all used metals were calculated for Multisorb (Figure 2). Despite the fact Multisorb is produced from peat, peat displayed a significantly lower capacity than Multisorb for all metals. Nevertheless peat displayed good results for silver and copper. The adsorption capacity for Ag of peat was similar to that of cork (Figure 2). The adsorption capacity of lignite was comparable to peat for Cu. Results for lignite, leonardite and fusinite for Ag were similar. The effectiveness of removing metal ions was the lowest in case of highly carbonified materials (bituminous coal, anthracite). Our results are in agreement with findings of Ong and Swanson (1966), who stated that the adsorption capacity of bituminous coal is much times less than that of the lignite. The adsorption capacity calcula- tions of activated carbon were not done well because of the precipitation of metals in solution.
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An Investigation on the Effects of Copper on Chenopodium album

An Investigation on the Effects of Copper on Chenopodium album

C. album is a wild vegetable that can grow in copper-contaminated soils, hence it poses a potential health risk as it is largely consumed by people as a leafy vegetable. There are few studies that have been conducted about C. album and its ability to accumulate copper [9]. This study is important by alerting people about the health risks they are exposed to when consuming the plant growing in copper-contaminated soils. Moreover this provides more information about the plant being used as an accumulator of copper which will help in minimizing copper contamination from the soil.
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