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EN
Copper is an important element necessary for proper functioning of living organisms. At the same time it is used for plant protection to combat crop plant pathogens. Copper preparations may affect not only pathogens but also entomopathogenic fungi used for plant protection. Copper ions limited surface growth of Paecilomyces farinosus mycelium. On the other hand in low concentrations copper ions stimulated spore germination and their pathogenicity. P. farinosus fungus strain: Sample 6;2 proved the least sensitive to copper ion effect.
PL
Miedź jest ważnym pierwiastkiem, niezbędnym do prawidłowego funkcjonowania żywych organizmów. Jednocześnie jest stosowana w ochronie roślin do zwalczania patogenów roślin uprawnych. Preparaty miedziowe mogą oddziaływać nie tylko na patogeny, ale także na stosowane w ochronie roślin owadobójcze grzyby. Jony miedzi ograniczały wzrost powierzchniowy grzybni Paecilornyces farinosus. Natomiast w małych stężeniach jony miedzi stymulowały kiełkowanie zarodników i ich patogeniczność. Najmniej wrażliwym grzybem P. farinosus na działanie jonów miedzi był szczep: Próbka 6;2.
EN
In this paper, the biosorption capacity of activated sludge sand bed was investigated for copper removal from wastewater. A sand bed consisting of three layers was used for the study: (1) filter gravel with a diameter of 2 to 3 mm, (2) a biological part inoculated with 200 ml of flocculent activated sludge with a dry weight of 5 kg/m3, (3) filter sand with a grain diameter of about 3 mm. The filter was fed with model wastewater prepared with sodium acetate, potassium nitrate, ammonium chloride, and potassium dihydrogen phosphate I and II basic. The source of Cu ions in the wastewater was CuSO4. The model wastewater used in this study was collected every 24 hours. The experiment was terminated when the concentration of Cu in the treated wastewater sample was equal to that in the treated wastewater. Such a phenomenon was indicative of the depletion of the sorption capacity of the tested bed, which was observed after 26 days. The concentration of copper in raw and effluent from the bed was studied using atomic absorption spectroscopy (ASA) in samples mineralized in nitric acid (HNO3) with the addition of perhydrol (H2O2). Two equilibrium models, Langmuir and Freudlich, were analyzed to study the absorption isotherms.
EN
The new P-podands (P3.1, P3.2, OP3.1 and OPH2.1) have been used as complexation agents in reactions with copper cations and the complexes obtained have been studied by NMR and kinetic methods. Two types of reactions, one between P-ligands and Cu(I) and the other between OP-podands and Cu(II), have been observed for the ligands studied.
EN
The paper deals with the modification of clay sorbents in order to improve the efficiency of of copper ions extraction from wastewater. The study examined the elemental, mineralogical and phase composition of kaolin and montmorillonite clays. The authors analyzed the sorption capacity of natural sorbents under static conditions before and after modification with hydrochloric acid, sodium chloride and sodium hydroxide. The work also determines the change in the physical and chemical properties of the sorbent after modification. The most optimal modification conditions for the purification of wastewater from copper ions are distinguished.
EN
Copper-ion activation plays a highly important role in cervantite (Sb2O4) flotation. Without metal-ion activation, cervantite cannot be floated by sodium oleate. In this study, flotation tests were conducted to study the effect of Cu2+ on the flotation behaviours of cervantite and quartz (SiO2) as the main gangue mineral. Metal-ion adsorption capacities, zeta potentials, solution chemistry and X-ray photoelectron spectra were analyzed to study the adsorption behavior and mechanism of copper ions and sodium oleate interaction with the minerals surfaces. The results demonstrate that under weakly acidic conditions, cervantite can be flotated and separated from quartz by the addition of copper ions. The reason is that copper ions can be selectively adsorbed on the cervantite surface under weakly acidic conditions, thereby promoting the adsorption of sodium oleate onto the cervantite surface by chemical adsorption. Conversely, copper ions are weakly adsorbed on quartz surfaces below pH 6.1, and sodium oleate cannot be adsorbed on quartz surfaces by chemical adsorption. The hydroxy copper species are integral to the selective activation of cervantite over quartz.
EN
This research aimed to identify the copper ion removal mechanism when using protonated dry alginate beads. This mechanism was explained through ion exchange between Cu ions and the protons from the functional groups of the alginate beads. Copper removal increased with stirring velocity, reaching values of 97.5 mg g-1 (97.5×10-3 kg/kg of PDAB) of dry alginate at 200 rev min-1, at a solution pH of 6.0 and a run time of 360 min. For the lowest level of copper concentrations, at 10 mg dm-3 (10×10-6 kg dm-3), full removal was attained. The removal kinetics was represented by a pseudo- first order model. A value of 0.0131 min-1 was found for the velocity constant. Under equilibrium conditions, the experiment data was fit to the Langmuir adsorption model, and the highest removal values were 270.3, 222.2 (222.2×10-3 kg/kg of PDAB) and 49 mg g-1 (49×10-3 kg/kg of PDAB) for pH values of 5.0, 3.5 and 2.5, respectively. These are higher than most sorbents used in the literature for copper removal. Increased temperature leads to higher Cu removal. The activation energy was calculated at 9.3 kJ mol-1 for the temperature range of 283 to 343K. Observations using SEM and composition measurements of the alginate cross-section taken by EDS showed a uniform distribution of the copper concentration through the structure of the alginate beads, independent of the solution pH, contact time and temperature.
EN
This work was aimed to analyze the effect of concentration of Cu.2+ and Pb.2+ ions in flotation process water with sphalerite activation, the analysis was performed at Cozamin Mining flotation circuit. This analysis demonstrated that (i) it was possible to determine the relationship between Sodium Cyanide and Ammonium Bisulfite used as depressants and Cu.2+ and Pb.2+ contents in the process water. (ii) It also proved the relationship between lead and iron content in the head with the Pb.2+ ions in process water. According to the data gathered and analysis performed, (iii) it was also determined that it was possible to reuse process water as long as the use of Ammonium Bisulfite was reduced and recommended replacing the use of Sodium Cyanide with Zinc Sulfate (ZnSO4) as a depressant of Sphalerite. Additionally, the concentration of Cu.2+ and Pb.2+ ions in the water should be controlled in a range of 10 to 20 ppm and 0.10 to 0.20 ppm, respectively.
8
Content available remote The effect of pH on the sorption of copper ions by alginates
88%
EN
The effect of pH on copper ions sorption by alginates has been investigated. The granules of the sorbent obtained from sodium alginate (type DMF, manufactured by KELCO) have been applied. By using a new method of gelation a biosorbent containing from 11.3 to 20.3% mas. of alginate has been produced. Investigations have been carried out at a constant temperature of 25°C and the pH values ranging from 3 to 5. The obtained experimental results have been described by the Langmuir equation. It has been found that with the increasing pH of the solution the maximum biosorbent sorption capacity increased.
EN
The sorption of divalent copper, natural sorbents of kaolinite and montmorillonite clays and carbon sorbent was studied on model solutions under static conditions. Quantitative characteristics of sorption process of copper ions were obtained. The degree of extraction of copper ions from solution was investigated, depending on the concentration of the initial solution and the weight ratio of the sorbent and volume of treated solution. The magnitude of sorption increases along with the increase in the volume of copper sulfate solution with a concentration of 0.02 M at a constant sample of sorbents. A higher carbon sorption capacity of the sorbent, in relation to ions of copper, was compared to kaolinite and montmorillonite clay. A higher sorption capacity of the carbon sorbent with respect to copper ions is established in the comparison with kaolinite and montmorillonite clay.
EN
The application of chitosan beads for the removal of copper ions from water is presented in the paper. The efficiency of sorption with glutaraldehyde on the either crosslinked or not beads arranged in the mass or on the surface is compared. Sorption kinetics of copper ions is presented.
EN
The binary and ternary complex formations of poly(methyl vinyl ether-co-maleic anhydride) (PMVEMA) with copper ions and with bovine serum albumin (BSA) in the presence of copper ions in phosphate buffer solution at pH = 7 were examined by the techniques of UV-visible, fluorescence, dynamic light scattering, atomic force microscopy measurements. In the formation of binary complexes of PMVEMA-Cu(II), the addition of copper ions to the solution of PMVEMA in phosphate buffer solution at pH = 7 forms homogeneous solutions when the molar ratio of Cu(II)/MVEMA is 0.5. Then the formations of ternary complexes of PMVEMA-Cu(II)-BSA were examined. Study analysis revealed that the toxicities of polymer-metal and polymer-metal-protein mixture solutions depend on the nature and ratio of components in mixtures.
EN
The binary and ternary complex formations of poly(methyl vinyl ether-co-maleic anhydride) (PMVEMA) with copper ions and with bovine serum albumin (BSA) in the presence of copper ions in phosphate buffer solution at pH = 7 were examined by the techniques of UV-visible, fluorescence, dynamic light scattering, atomic force microscopy measurements. In the formation of binary complexes of PMVEMA-Cu(II), the addition of copper ions to the solution of PMVEMA in phosphate buffer solution at pH = 7 forms homogeneous solutions when the molar ratio of Cu(II)/MVEMA is 0.5. Then the formations of ternary complexes of PMVEMA-Cu(II)-BSA were examined. Study analysis revealed that the toxicities of polymer-metal and polymer-metal-protein mixture solutions depend on the nature and ratio of components in mixtures.
PL
Haloizyt modyfikowany organicznymi związkami zawierającymi azot, wykorzystywany jako napełniacz polimerów, zastosowano do adsorpcji jonów Cu(II) z roztworu wodnego. Stwierdzono korelację ilości zaadsorbowanych jonów miedzi i ilości azotu związanego z powierzchnią haloizytu. Zwiększenie zawartości azotu na powierzchni haloizytu powodowało istotne zwiększenie zdolności adsorpcyjnej materiału w odniesieniu do jonów Cu(II).
EN
The halloysite modified with nitrogen-containing organic compounds (used as a polymers filler) was used to adsorb Cu(II) ions from an aqueous solution. A correlation was found between the amount of adsorbed copper ions and the amount of nitrogen bound to the halloysite surface. Increasing of the nitrogen content significantly increased the adsorption capacity of the material in relation to Cu(II).
14
Content available remote Copper ions as a factor determining the enzymatic activity of soil bacteria
75%
EN
The experiment bas been aimed at evaluating the war and the range of bacterial activity due to copper ions. Copper(II) chloride dihydrate was introduced into the soil at two rates to achieve the total copper content corresponding to weak and strong soil pollution by the element. After two-month soil incubation several hundreds of bacterial strains were isolated and ranges of proteolytic, amylolytic, and lipolytic activities were determined for every strain. Microorganisms were cultured on solid medium containing casein, tributyrin, or starch. Achieved results were compared with the same activity of microorganisms isolated from control soil. Contamination of soil with copper ions changed bacterial hydrolytic activity to a different degree, but it was not always statistically significant. In most cases, increase in hydrolytically inactive microorganism number and decrease in extremely active strains (from several to several dozens of per cents) was observed after copper chloride application. Higher differences in relation to control were recorded after weak pollution of soil with copper for amylolytic and lipolytic activities.
PL
Celem doświadczenia było ustalenie, czy jony miedzi mogą zmieniać zakres aktywności enzymatycznej populacji bakterii glebowych. Do gleby wprowadzono dihydrat chlorku miedzi(II) w dwóch dawkach, tak by całkowita zawartość miedzi odpowiadała słabemu i silnemu zanieczyszczeniu gleby tym pierwiastkiem. Po dwumiesięcznej inkubacji gleby, izolowano z niej szczepy bakteryjne (po kilkaset) i ustalano zakres ich aktywności proteolitycznej, amylolitycznej i lipolitycznej. Mikroorganizmy hodowano na podłożu stałym z kazeiną, tributyryną lub skrobią. Otrzymane wyniki porównywano do tej samej aktywności mikroorganizmów wyizolowanych z gleby kontrolnej. Zanieczyszczenie gleby jonami miedzi zmieniało w różnym zakresie aktywność hydrolityczną bakterii, jednak nie zawsze w sposób statystycznie istotny. W większości przypadków, po wprowadzeniu do gleby chlorku miedzi, zanotowano zwiększanie się ilości mikroorganizmów nie aktywnych hydrolitycznie oraz zmniejszenie udziału szczepów wybitnie aktywnych (od kilku do kilkudziesięciu procentów). W przypadku aktywności amylolitycznej i lipolitycznej większe różnice wobec kontroli odnotowano po słabym, a nie silnym zanieczyszczeniu gleby miedzią.
EN
The paper presents results of research on removal of Cu2+ ions from aqueous solutions by ion exchange method in concentration range of 10–1000 mg/L. For this purpose, following Purolite synthetic ion exchange resins were used: S 910, S 930, S 940, S 950 and C 160. The obtained results were interpreted based on the degree of solution purification and microstructural investigations. The regeneration possibility of used ion exchangers with a 10% hydrochloric acid solution was also investigated. Based on obtained results, it was determined that studied ion exchangers efficiently removed copper(II) ions from aqueous solutions, especially in low concentrations. Microstructural investigation made for tested materials after the sorption process clearly indicate that Cu2+ ions removal process was in accordance with ion exchange mechanism, which was confirmed by recorded SEM images. All ion exchangers except S 910, purified solutions from Cu2+ ions with an efficiency greater than 90% up to a concentration of 100 mg/L. In case of S 930 and S 940 ion exchangers, their efficiency was close to 100%. For higher concentrations, efficiency of studied ion exchangers decreased significantly. The lowest decrease in degree of copper(II) S 910 chelating resin with amidoxime groups was the least efficient. All studied ion exchangers can be regenerated with a 10% hydrochloric acid solution. The efficiency of this process varies from 53.1% to 80.5% depending on the used resins.
PL
W pracy przedstawiono wyniki badań dotyczące usuwania jonów Cu2+ z roztworów wodnych metodą wymiany jonowej w zakresie stężeń 10–1000 mg/L. W tym celu zastosowano żywice jonowymienne firmy Purolite: S 910, S 930, S 940, S 950 i C 160. Otrzymane wyniki zinterpretowano w oparciu o stopień oczyszczenia roztworu i badania mikrostrukturalne. Zbadano również możliwość rege¬neracji użytych jonitów za pomocą 10% roztworu kwasu solnego. Na podstawie otrzymanych wyników stwierdzono, że badane jonity skutecznie usuwały jony miedzi(II) z roztworów wodnych, szcze¬gólnie w niskich stężeniach. Badania mikrostrukturalne wykonane dla badanych materiałów po procesie sorpcji wyraźnie wskazują, że proces usuwania jonów Cu2+ zachodził zgodnie z mechanizmem wymiany jonowej, co potwierdzają zarejestrowane obrazy SEM. Na powierzchni badanych jonitów nie zaobserwowano mikrostrąceń. Wszystkie wymieniacze jonowe z wyjątkiem S 910 oczyszczały roztwory z jonów Cu2+ z wydajnością większą niż 90% do stężenia 100 mg/L. W przypadku jonitów S 930 i S 940 ich skuteczność było bliska 100%. W przypadku większych stężeń wydajność badanych jonitów znacząco malała. Najmniejszy spadek stopnia wydzielenia jonów miedzi(II) zaobserwowano dla kationitu C 160 zawierają¬cego grupy sulfonowe. Najmniej skuteczny okazał się jonit chelatujący S 910 z grupami amidoksymowymi. Wszystkie badane jonity można regenerować za pomocą 10% roztworu kwasu solnego. Wydajność tego procesu waha się od 53,1% do 80,5% w zależności od użytej żywicy jonowymiennej.
16
Content available remote Wykorzystanie zeolitów karpackich do usuwania jonów miedzi z roztworów wodnych
63%
EN
In this thesis possibilities of applied natural clinoptilolite comming from mind Sokirnitskoe in Ukraina and mind Niżny Hrabivec in Slovakia to removal copper ion from aquas solutions has been presented. In batch-type metod effluence of gradient of chemical regeneration, zeolite particle size and pH volue of metal solution on ion exchange process has been researched. In dynamical conditions efficiency of copper ion removal for two filtration speed has been compared. The regenaration time of clinoptilolite bed has been estimated.
PL
Przeprowadzono badania sorpcji jonów Cd(II) i Cu(II) na cząstkach iłu smektytowego. Do interpretacji wyników zastosowano izotermę Langmuira i Freundlicha. Parametry w równaniach oszacowano stosując metodę regresji liniowej i nieliniowej oraz metodę regresji liniowej dla dwóch zakresów stężeń początkowych jonów metali w roztworze. Najlepsze wyniki osiągnięto stosując metodę regresji nieliniowej lub metodę regresji liniowej dla dwóch zakresów stężeń początkowych jonów metali.
EN
The sorption of Cd(II) and Cu(II) ions onto smectite clays was studied. Equilibrium isotherms were analyzed using the Langmuir and Freundlich isotherms. A comparison between a linear and non-linear method of estimating the isotherm parameters was made. The results show that the non-linear and linear methods in two ranges of initial metal concentrations could be the best way to obtain the parameters.
18
63%
EN
The effect of pH on copper ions sorption by alginates has been investigated. The granules of the sorbent obtained from sodium alginate (type DMF, manufactured by KELCO) have been applied. By using a new method of gelation a biosorbent containing from 11.3 to 20.3% mas. of alginate has been produced. Investigations have been carried out at a constant temperature of 25°C and the pH values ranging from 3 to 5. The obtained experimental results have been described by the Langmuir equation. It has been found that with the increasing pH of the solution the maximum biosorbent sorption capacity increased.
EN
Iron and copper toxicity has been presumed to involve the formation of hydroxyl radical (·OH) from H2O2 in the Fenton reaction. The aim of this study was to verify that Fe2+-O2 and Cu+-O2 chemistry is capable of generating ·OH in the quasi physiological environment of Krebs-Henseleit buffer (KH), and to compare the ability of the Fe2+-O2 system and of the Fenton system (Fe2+ + H2O2) to produce ·OH. The addition of Fe2+ and Cu+ (0-20 μM) to KH resulted in a concentration-dependent increase in ·OH formation, as measured by the salicylate method. While Fe3+ and Cu2+ (0-20 μM) did not result in ·OH formation, these ions mediated significant ·OH production in the presence of a number of reducing agents. The ·OH yield from the reaction mediated by Fe2+ was increased by exogenous Fe3+ and Cu2+ and was prevented by the deoxygenation of the buffer and reduced by superoxide dismutase, catalase, and desferrioxamine. Addition of 1 μM, 5 μM or 10 μM Fe2+ to a range of H2O2 concentrations (the Fenton system) resulted in a H2O2-concentration-dependent rise in ·OH formation. For each Fe2+ concentration tested, the ·OH yield doubled when the ratio [H2O2]:[Fe2+] was raised from zero to one. In conclusion: (i) Fe2+-O2 and Cu+-O2 chemistry is capable of promoting ·OH generation in the environment of oxygenated KH, in the absence of pre-existing superoxide and/or H2O2, and possibly through a mechanism initiated by the metal autoxidation; (ii) The process is enhanced by contaminating Fe3+ and Cu2+; (iii) In the presence of reducing agents also Fe3+ and Cu2+ promote the ·OH formation; (iv) Depending on the actual [H2O2]:[Fe2+] ratio, the efficiency of the Fe2+-O2 chemistry to generate ·OH is greater than or, at best, equal to that of the Fe2+-driven Fenton reaction.
EN
Capacities of the pleustophytes in the purification of the aquatic environments in Polish climatic zone have been evaluated. Studies of bioaccumulation of copper(II) from culture media contaminated with 5, 10, 15 and 20 mg Cu/dm3 by the plants of Salvinia natans species were performed. The process was carried out for 14 days with the use of artificial plant-breeding species. The balance of the content of copper(II) in dry matter of plants and in the culture media was investigated. Capabilities of Salvinia natans to bioaccumulate copper(II) have been confirmed in all contaminated culture media.
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