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1

Removal of reactive blue 29 dye by adsorption on modified chitosan in the presence of hydrogen peroxide

Naghizadeh A., Nabizadeh R.

Environment Protection Engineering

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2016

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Vol. 42, nr 1

149--168

EN

Industrial effluents that carry dyestuff into natural water systems are serious environmental concern. Complex aromatic structures of dyes make them more stable and more difficult to remove from the effluents discharged into water bodies. In the present study, removal of reactive blue 29 dye with chitosan and modified chitosan with Cu complexes from aqueous solution was investigated in a batch adsorption system with respect to the changes in the contact time, pH of solution and chitosan dosage. Adsorption isotherms of the dye onto chitosan were also studied. The results revealed that the adsorption capacity of chitosan with Cu complexes is lower than that of chitosan without Cu complexes. Also effect of H2O2 on adsorption when we used chitosan without Cu complexes is more considerable. The results also demonstrated that adsorption capacity of reactive blue 29 dye on chitosan was higher at lower pHs. Finally, the Langmuir isotherm showed the best conformity to the equilibrium data.

2

Związki kompleksowe jonów miedzi(II) z peptydami

Pawlak J.

Zeszyty Naukowe. Chemia Spożywcza i Biotechnologia / Politechnika Łódzka

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2010

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Z. 74

137-150

PL

W organizmach żywych jony różnych metali odgrywają ważną rolę w wiązaniu i transporcie molekuł organicznych oraz są katalizatorami różnych procesów (między innymi w reakcjach redoks i kwas-zasada). Białka są jedną z głównych grup substancji organicznych, z którymi łączą się jony metali. Dowodem na to jest istnienie i rola metaloenzymów. Prawdopodobieństwo silnego wzajemnego oddziaływania pomiędzy jonami metali a białkami ujawniono dzięki reakcji biuretowej. Jednak nadal mato jest dostępnych informacji na temat struktury i sposobu ich połączenia. Badania kompleksów metali z różnymi oligopeptydami miały znaczący udział w zrozumieniu interakcji między jonami metali a białkami. Miedź odgrywa bardzo ważną rolę w prawidłowym funkcjonowaniu organizmów żywych, w których występuje zarówno w postaci kationów jak i kompleksów. Dlatego też niniejszy artykuł będący przeglądem literaturowym dotyczy interakcji jonów miedzi(II) z peptydami.

EN

Metal ions play significant role in living organism. They are involved in binding, transportation of biological molecules and different catalytic processes. Proteins are one of the main organic substances bonding metal ions called metalloproteins. They have many different functions in cells, such as enzymes, transport and storage proteins, and signal transduction. Studies of metal complexes with oligopeptides have critical impact on understanding interactions between metal ions and proteins. Copper is virtually required by all organisms both as cations and complexes for biological processes such as respiration, iron transport, oxidative stress protection, peptide hormone production, pigmentation, blood clotting and normal cell growth and development. Therefore this review concerns interactions of Cu(II) with peptides and their analogues.

3

ESR study of spin dynamics in (Er0.5Y0.5)2Cu2O5 solid solution

Typek J., Guskos N.

Materials Science Poland

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2006

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Vol. 24, No. 4

901--912

EN

Powder samples of (Er0.5Y0.5)2Cu 2O5 have been synthesized by a solid state reaction method. Electron spin resonance (ESR) measurements have been carried out on a Broker E 500 X-band spectrometer in the 4-300 K temperature range. A single, almost Lorentzian-shaped resonance line has been recorded for the whole investigated temperature range and its ESR parameters (integrated intensity, linewidth and resonance field) displayed a strong temperature dependence. The integrated intensity of the resonance line showed a pronounced maximum in low-temperature range and vanished at the transition to the antiferromagnetic ordering at TN = 11 K. The temperature at which the ESR integrated intensity reaches its maximum is different for the heating and cooling runs. Below 40 K, on approach to TN, the linewidth exhibited a divergent behaviour due to the onset of three-dimensional magnetic order. At higher temperatures (about 220 K), variations in ESR magnetic susceptibility suggest the presence of dynamical processes in copper-oxygen chains leading to the formation of copper dirners. The observed changes of the ESR parameters are interpreted in terms of 2D magnetism of the copper-oxygen system in the (Er 0.5Y0.5)2Cu2O5 solid solution.

4

Electron spin resonance study of copper(II) hydrogenmalonate dihydrate complex

Marczyński S., Typek J., Guskos N., Grech E., Kołodziej B.

Materials Science Poland

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2006

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Vol. 24, No. 4

1077--1085

EN

Copper(II) hydrogenmalonate dihydrate complex has been studied by using the electron spin resonance (ESR) method. Numerically deconvoluted ESR spectra of Cu(II) ions have been investigated at 4.2-295 K temperature range. The powder ESR spectrum has been described by three g-factors and additionally 1.5% of the existing spurious phases of a copper(II) complex has been revealed. The temperature dependence of the integrated ESR intensity has shown a Curic-Weiss type behaviour, consisting of two terms with different Curie-Weiss temperatures. The observed ferromagnetic interactions suggest the presence of two different paramagnetic species. It is proposed that the [Cu(H2O) 4][Cu(mal)2(H2O)2] copper(II) dimer complex is responsible for the low-temperature (T less than or equal 50 K) behaviour of the investigated sample.

5

Zmiana mechanizmu tribooksydacji oleju smarowego pod wpływem związków miedzi

Guzik J.

Tribologia

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2000

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nr 3

343-349

PL

Eksploatacyjna warstwa wierzchnia (EWW) powstaje na powierzchni tarcia wskutek chemisorpcji polarnych związków i następnie ich reakcji z utlenioną powierzchnią metalu. Wcześniejsze badania niepolarnych olejów modelowych po tarciu nie pozwoliły wykryć w nich produktów trobooksydacji. W artykule przedstawiono widma w podczerwieni ekstraktów metanolowych. Stwierdzono, że wprowadzenie CuO do heksadekanu zmienia kierunek tribooksydacji. W rezultacie powstaje EWW o innym składzie i zmniejsza się zużycie próbki stalowej.

EN

Service generated layer (SGL) is formed on the friction surface by chemisorption of polar compounds and theirs reaction with surface metal oxides .This mechanism is impossible with non-polar lubricants. It was found that the wear of steel sample lubricated with CuO dispersion in hexadecane was significant lower than in case of pure hexadecane (FIG.1). The SGL formed in CuO presence includes more kinds and more amounts of different oxidorganic compounds, in particular soaps and esters (L.3,4). In IR spectra of methanol extracts separeted from model oils after friction were detected (FIG.3): - aldehydes, ketones and alcohol's (in case of pure hexadecane-line 1), - only ketones in case of CuO dispersion (line2). This means, that different polar compounds formed in oil during friction forms different SGL's on friction surfaces.The final result is difference between tribological properties of friction pairs in cases with CuO and without CuO.

6

Odporność oleju smarowego na utlenianie w obecności związków miedzi i różnych antyutleniaczy

Guzik J., Olszewski W., Stachera B.

Journal of KONES

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1998

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Vol. 5, No. 1

85-89

PL

Utlenianie, czyli główny proces składowy starzenia olejów, zależy od wielu czynników. W artykule przedstawiono kolejny fragment badań laboratoryjnych wpływu związków miedzi na odporność oleju na utlenianie. Podczas eksploatacji w oleju smarowym zawsze znajdują się metaliczne, rozdrobnione cząstki zużycia węzłów tarcia, w tym cząstki miedzi. Zbadano współdziałanie związków miedzi z różnymi antyutleniaczami. Wykazano, że różne grupy antyutleniaczy różnie współdziałają ze związkami miedzi. Niektóre antyutleniacze inhibitują utlenianie oleju w obecności związków miedzi, natomiast inne katalizują proces utleniania.

EN

It was showed that cupric oxide increases the resistance to oxidation of base oils, but reduces the resistance to oxidation of commercial oils [1]. It was stated that CuO changes the mechanism of oxidation of model oil: in the presence of CuO less low-molecular organic acids is formed in the process of oxidation [3]. The paper contains the results of investigation of co-operation CuO with typical antioxidants. However, the results of oils oxidation tests (viscosity change, acid number and deposit content) are showed in the fig. 1. The effects of CuO co-operation depend on the antioxidant kind are different: - CuO shows antagonism at the collaboration with the low-temperature antioxidant AN-702, - CuO shows synergism with the high-temperature antioxidant A-880. Because lubricating oils contain antioxidants, adding to them formulations containing copper or its compounds can deteriorate resistance to oxidation of oils and accelerate oil agining. The influence of metallic wear particles formed during running-in can be similar.