Wyniki wyszukiwania - Biblioteka Nauki

1

Enzymy niklowe

100%

Wasilewski M.

Wiadomości Chemiczne

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1998

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tom [Z] 52, 3-4

207-241

EN

Nickel is now well recognized as an essential ultra trace element for bacteria and plants, where five distinct types of Ni-containing enzymes have been identified. It is also considered to be essential for animals and humans, however, its role in animal biochemistry is not well defined. The article, containing 10 figures and 201 bibliographic positions, provides a current summary of the properties of known nickel enzymes, with emphasis on structure-function relations. In the beginning the paper reviews occurrence of Ni in environment, and its biological importance. The relevant chemistry of nickel complexes has been shortly reviewed. Nickel enzymes are particulary prominent in the metabolism of anaerobic bacteria. For example, the metabolism of methanogens involves methyl-CoM reductase, nickel hydrogenase, acetyl-CoA synthase, and carbon monoxide dehydrogenase. Important enzyme for many bacteria, fungi, and plants is urease. Urease catalyzes the hydrolysis of urea, to from ammonia and carbamate. It was the first enzyme ever to be crystallized (Summer J.B., J. Biol. Chem., 1926, 69, 435; ibid., 1926, 70, 97). In 1975 Dixon and co-workers discovered that urease contains nickel at the active site (Dixon N.F. et.al., J. Am. Chem. Soc. 1975, 97, 4131). Twenty years later the X-ray crystal structure of the urease from Klebsiella aerogenes has been determined (Jabri E. Et al., Science, 1995, 268, 998). The enzyme is an (abg)3 trimer with each a-subunit having an (ab)8-barrel domain containing a binickel active site. A carbamylated lysine provides an oxygen ligand to each nickel, explaining why carbon dioxide is required for the activation of urease apoenzyme (Park I.S., Hausinger R.P., Science, 1995 , 267, 1156). In the paper the coordination geometry of nickel ions and the structure of active site, together with possible catalytic mechanism, are presented. [NiFe]-hydrogenases catalyze the two electron redox chemistry of H2. Crystallographic data on the hydrogenase from Desulfovibrio gigas were presented (Volbeda et al., J. Am. Chem. Soc., 1996, 118, 12989), giving new information on the structure and mode of action of its H2 activating place. The active centre was found to contain a heterodinuclear active site composed of a Ni centre bridged to an Fe centre by cysteinate ligands, and by oxygenspecies, which is proposed to be signature of the inactive from of the enzyme. The iron atom binds three diatomic ligands which are nonexchangeable triply bonded molecules (probably CO, CN- or NO). Based on the new structure possible modes of hydrogen binding and catalytic action of the active site are discussed. Methyl-coenzyme M reductase (MCR) catalyzes the final stage of the reduction of carbon dioxide to methane in methanogenic bacteria. The terminal step involves prosthetic group, Factor 430 (F-430), which in the resting state is a nickel (II) tetrapyrrole. Studies of F-430 in the enzyme complex suggest a hexacoordinate, octahedral Ni(II) environment, with two oxygen axial ligands. The spectral data of the active from of MCR are characteristic for F-430 in the Ni(I) oxidation state (Goubeaud M. Et al., Eur. J. Biochem. 1997, 243, 110), indicating that methyl-CoM reductase is activated when the enzyme-bound coenzyme F-430 is reduced to the Ni(I) state. The macrocycle can readily accommodate the structural changes that accompany reduction Ni(II) to Ni(I). Carbon monoxide dehydrogenase (CODH) catalyzes the reversible oxidation of CO to CO2, at an active site, called the cluster C, composed of an [4Fe-4S] cube with pentacoordinate Fe (called FCII), linked to a Ni(Hu Z. Et al., J. Am. Chem. Soc., 1996, 118, 830). Besides the enzymes that contain only CODH activity, there are the bifunctional enzymes that contain both CODH and acetyl-CoA synthase (ACS) activity (Ragsdale S. W., Kumar M., Chem. Rev., 1996, 96, 2515). This enzyme catalyzes reaction of CO at two separate Ni-FeS clusters. Oxidation of CO to CO2 is catalyzed by cluster C, while incorporation of CO into acetyl-CoA occurs at cluster A. A model of catalysis is proposed.

2

Effect of nickel on the growth and yielding of selected ornamental plant species

100%

Bosiacki M. , Wojciechowska E.

Aparatura Badawcza i Dydaktyczna

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2009

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tom T. 14, nr 3

5-11

EN

Pot experiment in an unheated greenhouse was carried out in the Department of Horticultural Plant Fertilization, University of Life Sciences in Poznań. Increasing nickel doses (control, 25, 50, 75,150 and 300 mg Ni x dm-3) were introduced to the substrate and their influence on the growth and yielding of three selected ornamental plants (Tagetes erecta 'Hawaii' Helianthus annus 'Pacino' and Amaranthus caudatus 'Atropurpureus') were studied. A smaller total yield of the aboveground parts of Tagetes erecta was obtained in all substrates, where nickel was added, in comparison with the control (without any metal addition). Total yield of the aboveground part of Helianthus annus significantly decreased with the highest Ni dose (300 mg x dm-3). The highest total yield of the aboveground part of Amaranthus was shown by the dose of 150 mg Ni x dm-3. Phytotoxic actions of Ni (chlorosis, withering of leaf borders, poorer flowering) were observed with the dose of 300 mg Ni x dm-3 substrate, but in the remaining combinations, there were no clear symptoms of any harmful effects caused by the nickel. From among the studied species of ornamental plants Amaranthus caudatus can be used in the remediation of soils polluted with nickel.

PL

W doświadczeniu wazonowym przeprowadzonym w szklarni nieogrzewanej w Katedrze Nawożenia Roślin Ogrodniczych, Uniwersytetu Przyrodniczego w Poznaniu badano wpływ rosnących dawek Ni (kontrola, 25, 50, 75, 150, 300 mg x dm-3 podłoża), wprowadzonych do podłoża na wzrost i plonowanie trzech wybranych gatunków roślin ozdobnych: aksamitka wyniosła (Tagetes erecta 'Hawaii'), słonecznik ogrodowy (Helianthus annus 'Pacino'), szarłat zwisły (Amaranthus caudatus 'Atropurpureus^. Mniejszy plon ogólny części nadziemnej Tagetes erecta uzyskano we wszystkich podłożach, do których wprowadzono nikiel, w porównaniu do plonu uzyskanego w podłożu bez dodatku tego metalu. Plon ogólny części nadziemnej Helianthus annus uległ wyraźnemu zmniejszeniu przy najwyższej dawce niklu wprowadzonej do podłoża. Amaranthus caudatus największy plon ogólny części nadziemnej uzyskał w podłożu, do którego wprowadzono 150 mg Ni x dm-3. Fitotoksyczne działanie Ni (chloroza, brzegowe zamieranie liści, słabsze kwitnienie) zaobserwowano przy poziomie 300 mg Ni x dm-3 podłoża, w pozostałych kombinacjach nie stwierdzono wyraźnych objawów szkodliwego działania niklu. Spośród badanych gatunków roślin ozdobnych Amaranthus caudatus może być wykorzystywany do zagospodarowywania gleb skażonych niklem.

3

Nickel Mediated Coupling of Organic Ligands

100%

Pasynkiewcz S. , Pietrzykowski A. , Olędzka E. , Wang J.

Polish Journal of Chemistry

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2003

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tom Vol. 77 / nr 5

701-707

EN

Reactions of nickelocene, NiCp2, with organolithium compounds RLi (R = -C_CPh; -CPh=CPh2; -CPh3, -CPh2SiMe3), where R does not contain _- and _-hydrogen atoms, have been studied. It was found that {CpNiR}, formed in the first step of the reaction, underwent coupling with the formation of {(NiCp)2} and R-R. As organolithium substrates are readily available, and yield of coupling products was high (from over 60% to ~ 90%), the studied reactions could be applied as synthetic methods for preparation of wide range of R-R type organic compounds. In order to improve yield of the products and to prevent very active {(NiCp)2} species from further reactions, NiCp2 and LiR were reacted in the presence of PhC_CMe, what led to the formation of only two products: (NiCp)2_PhC_CMe complex and R-R. These products were easily separated by column chromatography on neutral alumina, leading to the isolation of R-R in high yield.

4

Content of copper and nickel in soils of Vistula river catchment

100%

Skorbiłowicz E. , Samborska A.

Journal of Ecological Engineering

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2014

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tom Vol. 15, nr 2

53--59

EN

Metal pollution attracts growing interest mainly due to their toxic effects on the entire natural environment. It is therefore necessary to monitor, not to exceed acceptable standards of elements in ecosystems. Heavy metals in soils are derived from natural and anthropogenic sources. The purpose of this article is to present the contents of copper and nickel in agricultural soils within the Vistula river catchment based on research carried out by the Institute of Soil Science and Plant Cultivation in the period since 1995 to 2010. The assessment of a degree of soil contamination by these elements according to standards has been also performed. It has been proven that about 91% of agricultural soils in Vistula river catchment shows natural (0°), while approximately 9% higher (Io) copper concentrations. It was found that in the total agricultural area of the Vistula river catchment, soils not contaminated with nickel (0°), with elevated (Io), and weakly contaminated soils (IIo) are respectively 85%, 11%, 4% of the analyzed soils area. There was a significant relationship between the content of copper and nickel in soils and such features as organic matter and pH. Analysis of results confirmed that the highly developed industrial activity affects the increased amount of pollutants in soils; the greatest accumulation occurred in soils of the upper Vistula river catchment, which is caused primarily by interaction of the Upper Silesian Industrial District.

5

Assessment of selected structural properties of orthodontic arches

100%

Zięty A. , Grygier D. , Detyna J. , Sarul M.

Engineering of Biomaterials

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2018

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tom Vol. 21, no. 148

47

6

Zinc and copper fractions in soil contaminated with nickel

100%

Kuziemska B. , Wieremiej W. , Jaremko D.

Polish Journal of Soil Science

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2015

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tom 48

|

nr 1

EN

Soil subject to a three-year pot experiment was analyzed, in which the following factors were considered: (i) soil contamination with nickel (0, 75, 150 and 225 mg Ni kg⁻¹ of soil); (ii) liming (0 Ca and Ca in a dose calculated according to 1 Hh of soil); (iii) organic fertilization (with no organic fertilization, rye straw and brown coal from the Turów coalmine). The test plant was orchardgrass, which was harvested in the amount of four cuts each year of the experiment. The copper and zinc fractions were assessed using the BCR method, whereas the pH was calculated using the potentiometer method. The total content of copper and zinc in the analyzed soil did not exceed the values of the geochemical background of the soils of Poland. No impact of the varied content of nickel in the soil on the total content and distribution of Cu and Zn was found in the investigated fractions. Liming caused an increase in the total content of zinc in the analyzed soil and a decrease in the content of Cu and Zn in the F1 fraction. The straw and brown coal caused an increase in the content of both metals in the soil in the F3 fraction.

PL

Analizowano glebę po trzyletnim doświadczeniu wazonowym, w którym uwzględniono następujące czynniki: 1. zanieczyszczenie gleby niklem (0,75, 150 i 225 mg Ni kg⁻¹ gleby); 2. wapnowanie (0 Ca i Ca w dawce wyliczonej wg 1 Hh gleby); 3. nawożenie organiczne (bez nawożenia organicznego, słoma żytnia i węgiel brunatny pochodzący z kopalni w Turowie). Rośliną testowa była kupkówka pospolita, której w każdym roku eksperymentu zebrano po cztery pokosy. Frakcje miedzi i cynku oznaczono metodą BCR, a pH metodą potencjometryczną. Ogólna zawartość miedzi i cynku w analizowanej glebie nie przekraczała wartości tła geochemicznego gleb Polski. Nie wykazano wpływu zróżnicowanej ilości niklu w glebie na zawartość ogólną i rozmieszczenie Cu i Zn w wydzielonych frakcjach. Wapnowanie spowodowało zwiększenie ilości ogólnej cynku w analizowanej glebie oraz zmniejszenie udziału Cu i Zn we frakcji F₁. Słoma i węgiel brunatny spowodowały zwiększenie w glebie ilości obu metali oraz ich udziału we frakcji F₃.

7

Leaching behaviour of a turkish lateritic ore in the presence of additives

100%

Basturkcu H. , Acarkan N.

Physicochemical Problems of Mineral Processing

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2016

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tom Vol. 52, iss. 1

112--123

EN

This paper investigates the dissolution mechanism of a lateritic nickel ore from the Caldag Region of Manisa in Turkey. The ore sample contained 1.2% Ni, 24.8% Fe, and 0.062% Co. The optimum leaching conditions were found to be temperature 80 oC, particle size -74 μm, H2SO4 concentration 200 g/dm3, solids ratio (by weight) 10% and leaching duration 8 h. The extractions of 98.2% Ni, 98.6% Fe and Co 98.9% were obtained under these conditions. Additionally, the effects of additional substances such as NaCl, Na2S2O5, Na2SO4, and KCl were investigated in order to decrease the leaching duration. The results showed that the additives accelerated the leaching kinetics and achieved nearly the same nickel and cobalt extractions at the end of 4 h compared to the results obtained after 8 h without the additives. If the additives containing chlorine were used, it was determined that the iron extraction showed no increase, although both the nickel and cobalt extractions increased.

8

Preparation of Nickel Nanoparticles Using Nickel Raffinate Separated by Solvent Extraction from The Spent FeCl3 Etching Solution

100%

Park I.-J. , Swain B. , Kim D.-W. , Kim G.-H. , Han D.-H. , Jung H.-C.

Archives of Metallurgy and Materials

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2019

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tom Vol. 64, iss. 2

531--534

EN

FeCl3 bearing etching solution is mainly used for etching of metals used in shadow masks, PCBs and so on. Due course of Invar alloy etching process the FeCl3 bearing etching solution get contaminated with Ni2+ which affect adversely the etching efficiency. Hence, FeCl3 bearing etching solution discarded after several cycle of operation causes an environmental and economic problem. To address both the issues the etching solution was purified through solvent extraction and remained Ni2+ recovered by wet chemical reduction using hydrazine. For optimum Fe3+ extraction efficiency, various extraction parameter were optimized and size and morphology of the recovered pure Ni powder was analyzed. The reported process is a simple process to purify and recover Ni from industry etching solution.

9

Macrophytes as Ełk River Quality Status Evaluation Indicators Based on Example of Nickel

100%

Skorbiłowicz E. , Skorbiłowicz M. , Zamojska E. , Ofman P. , Wójtowicz P.

Journal of Ecological Engineering

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2016

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tom Vol. 17, nr 3

155--160

EN

The aim of the study was to analyze the content of Ni in fractions of 1.0–0.2 mm, 0.2–0.1 mm, 0.1–0.063 mm, 0.063–0.02 mm, and <0.02 mm of river bottom sediments and plants (root, stem, leaf) of broadleaf cattail (Typha latifolia), yellow water lilies (Nuphar lutea), and cowbane (Cicuta virosa). Nickel content in bottom sediment was slightly higher than the geochemical background. The largest amounts of Ni were associated with the finest fraction, while the smallest with the thickest fraction. The highest content of this element was recorded at the point Ełk Barany, which was connected with developing industry in the city of Ełk. All of the tested plants showed greater Ni contents than the amount naturally occurring in plants. In most cases, most of Ni was associated with plant roots, and the least with leaves. It has been proven that aquatic plants can be good indicators of the aquatic environment status.

10

Removal of Ni2+from Aqueous Solutions by Adsorption Onto Magnetic Multiwalled Carbon Nanotube Nanocomposite

100%

Konicki W. , Pełech I. , Mijowska E.

Polish Journal of Chemical Technology

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2014

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tom 16

|

nr 2

87-94

EN

The removal of Ni2+ from aqueous solution by magnetic multiwalled carbon nanotube nanocomposite (MMWCNTs-C) was investigated. MMWCNTs-C was characterized by X-ray Diffraction method (XRD), High-Resolution Transmission Electron Microscopy (HRTEM), surface area (BET), and Fourier Transform-Infrared Spectroscopy (FTIR). The effects of initial concentration, contact time, solution pH, and temperature on the Ni2+ adsorption onto MMWCNTs-C were studied. The Langmuir and Freundlich isotherm models were applied to fit the adsorption data. The results showed that the adsorption isotherm data were fitted well to the Langmuir isotherm model with the maximum monolayer adsorption capacity of 2.11 mg g–1. The adsorption kinetics was best described by the pseudo-second-order model. The thermodynamic parameters, such as ΔHo, ΔGo and ΔSo, were also determined and evaluated. The adsorption of Ni2+ is generally spontaneous and thermodynamically favorable. The values of ΔHo and ΔGo indicate that the adsorption of Ni2+ onto MMWCNTs-C was a physisorption process.

11

Preparation of Nickel Powders by Reduction of Nickel Hydroxide Using the Taylor Fluid Flow

100%

Park I.-J. , Kim D.-W. , Kim G.-H. , Chae H.-J. , Jung H.-C.

Archives of Metallurgy and Materials

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2018

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tom Vol. 63, iss. 3

1443--1447

EN

In this study, Ni(OH)2 was synthesized by the continuous reaction by the Taylor fluid flow and compared with those prepared from the conventional batch type reaction. The nickel powders were synthesized by reduction of Ni(OH)2 in an aqueous solution with hydrazine hydrate acting as the reductant. And then the characteristics of the nickel powder according to the synthesis method were compared. The average particle size of the synthesized Ni(OH)2 using Taylor reactor was generally decreased about 1.5~2.5 times more than the batch reaction. The nickel powders prepared by the batch reaction highly agglomerated with non-uniform particles. In the Taylor reaction, the agglomeration of particles was broken and uniform nickel powder was produced.

12

Adsorption of Ni2+ from aqueous solution by magnetic Fe@graphite nano-composite

100%

Konicki W. , Pelka R. , Arabczyk W.

Polish Journal of Chemical Technology

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2016

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tom Vol. 18, nr 4

96--103

EN

The removal of Ni2+ from aqueous solution by iron nanoparticles encapsulated by graphitic layers (Fe@G) was investigated. Nanoparticles Fe@G were prepared by chemical vapor deposition CVD process using methane as a carbon source and nanocrystalline iron. The properties of Fe@G were characterized by X-ray Diffraction method (XRD), High-Resolution Transmission Electron Microscopy (HRTEM), Fourier Transform-Infrared Spectroscopy (FTIR), BET surface area and zeta potential measurements. The effects of initial Ni2+ concentration (1–20 mg L−1 ), pH (4–11) and temperature (20–60°C) on adsorption capacity were studied. The adsorption capacity at equilibrium increased from 2.96 to 8.78 mg g−1 , with the increase in the initial concentration of Ni2+ from 1 to 20 mg L−1 at pH 7.0 and 20°C. The experimental results indicated that the maximum Ni2+ removal could be attained at a solution pH of 8.2 and the adsorption capacity obtained was 9.33 mg g−1 . The experimental data fitted well with the Langmuir model with a monolayer adsorption capacity of 9.20 mg g−1 . The adsorption kinetics was found to follow pseudo-second-order kinetic model. Thermodynamics parameters, ΔHO, ΔGO and ΔSO, were calculated, indicating that the adsorption of Ni2+ onto Fe@G was spontaneous and endothermic in nature.

13

Electroplating nickel onto uranium as fission-recoil barrier

100%

Cieszykowska I. , Żółtowska M. , Mielcarski M.

Nukleonika

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2009

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tom Vol. 54, No. 1

29-32

EN

Plating experiments have been performed in order to obtain fission recoil barriers on low-enriched uranium (LEU) metal foils used as targets suitable for the production of 99Mo. The results of Ni deposition obtained in electroplating and electroless plating baths are presented. The best method of pretreatment uranium prior to plating is suggested. It was found that etching in solutions containing NiCl2 gave better results on uranium rods, whereas electroplating produces coatings with the desired level of adherence and coverage on uranium foils. The thickness of the nickel plates, evaluated both microscopically and gravimetrically, is sufficient to act as a fission recoil barrier.

14

Gold as Promoter of Nickel Supported Catalysts for Semi Combustion of Methane

100%

Maniecki T. P. , Bawolak K. , Mierczyński P. , Jóźwiak W. K.

Polish Journal of Chemistry

|

2008

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tom Vol. 82, nr 12

2389-2399

EN

The gold influence on catalytic activity, stability and carbon deposition of supported nickel based catalysts was studied. The monometallic 5%Ni/Al2O3 and bimetallic 5%Ni-x%Au/Al2O3 (x = 2, 1, 0.5, 0.25, 0.1) systems were prepared by wet impregnation. The catalytic tests in partial oxidation of methane at 25-900 graduate C and long term stability tests at 900 graduate C during 24 h were carried out. The CH4 dissociative decomposition and CO disproportionation processes were run at the same temperature range. Carbon deposition was studied by TG analysis and catalysts investigations by TPR and XRD measurements. The results indicated that gold addition improved both catalytic activity and resistance towards carbon deposition.

15

Removal of Ni2+ from Aqueous Solutions by Adsorption Onto Magnetic Multiwalled Carbon Nanotube Nanocomposite

100%

Konicki W. , Pełech P. , Mijowska E.

Polish Journal of Chemical Technology

|

2014

|

tom Vol. 16, nr 2

87--94

EN

The removal of Ni2+ from aqueous solution by magnetic multiwalled carbon nanotube nanocomposite (MMWCNTs-C) was investigated. MMWCNTs-C was characterized by X-ray Diffraction method (XRD), High-Resolution Transmission Electron Microscopy (HRTEM), surface area (BET), and Fourier Transform-Infrared Spectroscopy (FTIR). The effects of initial concentration, contact time, solution pH, and temperature on the Ni2+ adsorption onto MMWCNTs-C were studied. The Langmuir and Freundlich isotherm models were applied to fit the adsorption data. The results showed that the adsorption isotherm data were fitted well to the Langmuir isotherm model with the maximum monolayer adsorption capacity of 2.11 mg g–1. The adsorption kinetics was best described by the pseudo-second-order model. The thermodynamic parameters, such as ΔHo, ΔGo and ΔSo, were also determined and evaluated. The adsorption of Ni2+ is generally spontaneous and thermodynamically favorable. The values of ΔHo and ΔGo indicate that the adsorption of Ni2+ onto MMWCNTs-C was a physisorption process.

16

Composite coatings with nickel matrix and graphene as dispersed phase

100%

Gajewska-Midziałek A.

Polish Journal of Chemical Technology

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2018

|

tom Vol. 20, nr 1

54--59

EN

The paper presents the results of the studies of nickel-graphene composite coatings deposited by the electrochemical reduction method. A bath with low concentration of nickel ions, graphene as dispersed particles and organic compounds were used for deposition of the composite coatings nickel-graphene. The results of investigations of coatings deposited from the electrolyte containing 0.33, 0.5 and 1 g/dm3 graphene and two surface-active compounds were shown. The particles content in the coatings, the surface morphology, the cross-sectional structures of the coated samples, thickness and internal stresses were measured. Voltammetric method was used for examination of the corrosion resistance of samples of composite coatings in 0.5 M NaCl solution. The obtained results suggest that the content of incorporated graphene particles increases with an increasing amount of graphene in plating bath. The applications of organic addition agents was advantageous because it caused compressive stresses in the coatings. All of the nickel-graphene composite coatings had better corrosion resistance than the nickel coatings.

17

Biosorption of Cu2+ and Ni2+ ions from aqueous solutions using waste dried activated sludge biomass

100%

Aslan S. , Yildiz S. , Ozturk M.

Polish Journal of Chemical Technology

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2018

|

tom Vol. 20, nr 3

20--28

EN

Adsorption of Cu(II) and Ni(II) ions onto the waste powdered activated sludge biomass (PWB), which was obtained from the biological wastewater treatment plant, was investigated in this experimental study. The effects of contact time, pH, temperature, initial sorbate and sorbent concentrations on the adsorption were determined. The BET surface area, pore volume, and pore diameter of PWB were found to be about 0.51 m2/g, 0.0053 cm3/g, and 41.4 nm, respectively. Considering the R2 value, qexp and qcal , the Langmuir and Freundlich models were well described for Cu(II) and Ni(II) adsorption, respectively. The adsorption mechanism of Cu(II) and Ni(II) onto the PWB could be better simulated by the pseudo-second-order kinetic mechanism than the pseudo-first-order, intra particle diffusion and Elovich models. Thermodynamic aspects of the adsorption of heavy metals were also investigated. Considering the applied desorbing agents for reuse of PWB for Ni(II) recovery, desorption cycle is not feasible due to the deterioration of the PWB structure.

18

Content of Selected Heavy Metals In Ni-Contaminated Soil Following the Application of Halloysite and Zeolite

100%

Radziemska M. , Mazur Z.

Journal of Ecological Engineering

|

2016

|

tom Vol. 17, nr 3

125--133

EN

Nickel has been listed as a priory control pollutant by the United States Environmental Protection Agency (US EPA). Compared with other methods, the combination of vegetation and the addition of mineral sorbents to heavy metal-contaminated soils can be readily applied on a large scale because of the simplicity of technology and low cost. Halloysite and zeolite, among others, can be used for this purpose. A greenhouse study was performed to evaluate the feasibility of using natural zeolite, as well as raw and modified halloysite for the remediation of simulated Ni-contaminated soil. The soil was spiked with five doses of nickel, i.e. 0 (control), 80, 160, 240 and 320 mg·Ni kg-1·soil. The average accumulation of heavy metals in nickel-contaminated soil was found to follow the decreasing order of Ni>Zn>Cr>Cu>Pb. The highest reduction of Pb content was observed in soil samples taken from pots containing 80 and 160 mg·kg-1 of Ni along with the addition of modified halloysite. The strongest effects were caused by natural zeolite, which significantly reduced the average content of chromium. Contamination at 320 mg Ni·kg-1

19

Use of sulfate-reducing bacteria and different organic fertilizer for bioremediation of ex-nickel mining soils

100%

Bakhtiar , Sukoso , Saida

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2021

|

tom Vol. 30, No. 4

561--572

EN

The microbiological activity associated with exmining soil remediation can be considered useful to accelerate the contaminant degradation. The use of sulfate-reducing bacteria (SRB) and organic matter exhibits potential in improving ex-nickel mining soil quality. The purpose of this study was to examine the ability of SRB in several organic fertilizers to reduce sulfate and nickel ions, and to increase pH of soil from nickel in mining areas. This study used the bacteria collection of the Soil Laboratory of the Faculty of Agriculture, Universitas Muslim Indonesia. Those were previously isolated from two cultivating pond of milkfish in the Kuri area of Maros Regency, South Sulawesi, Indonesia. The soil samples were collected from ex-mining areas of the Vale Indonesia Enterprise in Soroako, South Sulawesi, Indonesia. Those were mixed with organic fertilizers, generated from sugarcane sludge, manure, and Quickstick (Gliricidia sepium) leaves, each with 50 and 100 g doses. The 5 kg soil samples were put into a pot and mixed evenly with organic fertil- izers. A general linear model (GLM) repeated measures analysis of variance (ANOVA) was adopted to analyze the data. The results of this study indicate that the application of SRB and fertilizer was effective in reducing concentration of sulfate and nickel. Among the three types of organic fertilizers, manure was effective in reducing sulfate and nickel concentrations, while Quickstick fertilizer was the more effective in stabilizing pH level. Fertilizer doses exhibited a significant effect on decreasing sulfate and nickel concentrations, but it exhibited no significant effect on stabilizing pH levels. At 10 days after treatment (DAT), the sulfate concentration decreased from 2,530 ppm to 1,443 ppm in treatment of SRB and manure with dose of 50 g and 1,363 ppm with that of 100 g. At the end of the observation (30 DAT), those were decreased to 1,217 ppm in treatment of SRB and manure with doses of 50 g and 1,167 ppm with that of 100 g. Among the three types of organic fertilizers used, Quickstick demonstrates the more effective reduction rate. At 10 DAT, pH increased in SRB treatment by 7.06 at a concentration of 50 g and 7.01 at a concentration of 50 g. At the end of the observation (30 DAT), the pH became 6.67 at a concentration of 50 g and 6.82 at a concentration of 50 g. The nickel concentration decreased from an origin concentration to 1,950 ppm in treatment of SRB and manure with doses of 50 g and 1,690 ppm with that of 100 g. Thus, the application of manure fertilizer and the addition of SRB is recommended for bioremediation of sulfate and nickel from ex-mining soil.

20

Activity of Antioxidant Enzymes under Induced Oxidative Stress

100%

Deska M.

Journal of Ecological Engineering

|

2020

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tom Vol. 21, nr 7

42--51

EN

Reactive oxygen species (ROS) include both oxygen free radicals and highly reactive oxygen compounds (such as ozone, singlet oxygen). They are formed in many metabolic processes, as well as under the influence of various environmental factors. Their impact on cells depends on their concentration and the duration of the process. Excessive level of ROS in a cell leads to oxidative stress. One of the defence mechanisms against ROS corresponds to antioxidant enzymes including SOD and CAT. This paper defines the changes in the activity of antioxidant enzymes caused by oxidative stress induced by nickel and paraquat in tissue of Acheta domesticus L, derived from various development lines. The obtained results defining the activity of SOD and CAT indicated the differences among individual tissues and the midgut showed the highest activity. Increased activity in relation to the control group results of CAT and SOD in the midgut and fat body of B-line individuals treated with pro-oxidant (particularly nickel) and inhibition of the CAT activity in the midgut of L-line crickets influenced by pro-oxidant indicate that the conducted screening changes the biochemical response to the stress factors. Moreover, the obtained results may indicate the relation of the activity of SOD and CAT with the lifespan of the tested insects.