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1

Green preparation of argentum tungstate and characterization as nanorod with catalytic evaluation for synthesizing tetracyclic xanthenes and validation as anti-TB

Almehizia Abdulrahman A., Al-Omar Mohamed A., Naglah Ahmed M., Ghabbour Hazem A., Hassan Ashraf S., Khatab Tamer K.

Polish Journal of Chemical Technology

|

2024

|

Vol. 26, nr 4

1--7

EN

The work presented a facile, one-step procedure as a green assembly process for preparing silver tungstate nanorod by hydrothermal technique via a chemical reaction between silver nitrate and sodium tungstate. The synthesized precipitate was characterized using X-ray diffraction (XRD) transmission electronic microscope (TEM) and scanning electron microscopy (SEM) to ensure the formation of crystallization and single-phase material. The prepared nanorods undergo a catalytic evaluation to synthesize tetrahydrobenzo[a] xanthene-11-one derivatives by a one-pot reaction of β-naphthol, dimedone, and aromatic aldehyde with a catalytic amount of silver tungstate under the solvent-free condition at 60–70°C. ArgC is one of the L-arginine biosynthetic pathways of mycobacterium tuberculosis. The molecular docking explains that all the synthesized compounds presented high ligand ability for the targeted enzyme compared with xanthene-9-carboxylic acid as a reference.

2

Surface Modification of the Ti-35Nb-7Zr-5Ta Bio Alloy by the PM-EDM Route

Hayyawi Ahmed Rabeea, Al-Ethari Haydar, Haleem Ali Hubi

Advances in Science and Technology. Research Journal

|

2024

|

Vol. 18, no. 3

140--150

EN

One of the most attractive β-Ti alloys is Ti–35Nb–7Zr–5Ta wt% (TNZT) alloy, which has one of the minimal Young’s moduli among the β-Ti family (about 55 GPa) and contains no cytotoxic elements. On the other hand, β-type Ti alloys are susceptible to bacterial infection because they lack an antibacterial function and can get contaminated quickly after implantation, making surface modification a keyway to improve these alloys' antibacterial properties. A recently created technique called powder mixed-EDM can improve machining, mechanical, and biological properties at the same time. In this research, silver was added to the dielectric fluid during PM-EDM of Ti-35Nb-7Zr-5Ta wt% alloy prepared by powder metallurgy route. The surface composition, Brinell hardness, corrosion resistance, ion release, and antibacterial properties were evaluated for TNZT alloy before and after surface modification. The results show better hardness and corrosion resistance as well as lower ion release for the PM-EDMed specimen due to the presence of Ag, oxides, and carbides such as NbC, TiC, TiO2, ZrO2, and Nb2O5 that’s deposited and embedded as a hard phase in the recast layer of the machined surface. Also, the antibacterial property of the PM-EDMed specimen is effectively improved as silver is an antibiotic with a wide range, so it has favorable antibacterial properties for Gram-negative and Gram-positive bacteria.

3

Recovery of base and precious metals from scrap TV boards using zig-zag air separator

Yazici Ersin Yener, Celep Oktay, Ibrahim Boulama Omar Yacine Lawan, Deveci Haci

Physicochemical Problems of Mineral Processing

|

2023

|

Vol. 59, iss. 5

art. no. 168255

EN

Waste of Electrical and Electronic Equipments (WEEE) is one of the fastest growing waste streams in the world. The treatment of WEEE with high content of precious metals (Au in particular) has received the most attention due to their high economic potential. The development of simple, environmentally friendly and cost-effective methods for the recovery of metals from “low-value” WEEE (e.g., <100 g/t Au) is important from the circular economy perspective. In this study, the separation of base (Cu) and precious (Ag) metals from scrap TV boards (STVBs) by using a zig-zag air separator was investigated. Size-reduced scrap STVBs (-1 mm) were subjected to separation tests after the removal of the fine fraction (-0.1 mm). The sized scrap material (-1 +0.1 mm) was determined to have a metal content of 15.4% Cu, 47 g/t Ag and 0.05% Fe, with no gold. In the air separation tests, the effect of air flow rate (4-16 m/s) on the recovery of metals was studied. Increasing the air flow rate resulted in low metal recoveries with concurrent high metal grades in the concentrate. Separation efficiency (%) calculations showed that the most efficient separation is obtained at the highest air flow rate of 16 m/s. At this flow rate, 15.4% of the material was recovered in the concentrate which contains 62.3% Cu and 198 g/t Ag with recoveries of 63.3% Cu and 73.9% Ag. The findings indicated that zig-zag air separators can be used to obtain a metal-rich fraction under suitable conditions of the flow regime.

4

Kinetics of simultaneous recovering of Au and Ag from CTs by chloridizing volatilization methods

Wang Weiwei, Li Zhengyao, Yang Shanshan, Ma Kai, Gao Xin, Han Shaoqi, Hou Shaochun, Miao Hecheng

Physicochemical Problems of Mineral Processing

|

2023

|

Vol. 59, iss. 6

art. no. 172522

EN

Cyanide Tailings (CTs) are known as hazardous resources that accumulate hundreds of millions of tons, threatening the ecological environment. This work proposes an eco-friendly and efficient way to recover gold and silver from CTs. The effects of calcium chloride dosage, silicon dioxide dosage, pellet moisture content, roasting temperature, and roasting time on Au and Ag chloridizing volatilization were studied. The kinetics of simultaneously recovering of gold and silver from cyanide Tailings by chlorination roasting was investigated. It was determined that the chloridizing volatilization rates increased with increasing calcium chloride dosage, temperature and decreasing silicon dioxide dosage, pellet moisture content. The chloridizing volatilization kinetics followed a shrinking core model, with inter-diffusion through gangue layer as the rate determining step. This finding is in accordance with the apparent activation energy (Ea) of 24.01 kJ•mol-1 (Au) and 24.62 kJ•mol-1 (Ag). The orders of reaction with respect to moisture content, temperature, calcium chloride dosage and silicon dioxide dosage were also achieved. The rate of reaction based on diffusion-controlled process can be expressed by semi-empirical equations. The control steps of the gold and silver recovery process were investigated by the kinetic study, which provided theoretical guidance for the optimization of the method.

5

Research on New Al-Ag-Mo Alloys Dedicated to Wire Applications in Overhead Power Lines

Grzebinoga Justyna, Mamala Andrzej, Ściężor Wojciech, Kowal Radosław

Journal of Casting & Materials Engineering

|

2023

|

Vol. 7, no. 1

9--14

EN

The latest research work in the field of electric power systems focuses on the development of new wire materials which will allow the increase of the transmission capacity of power lines currently in use. The reason for this research was the often limited possibilities of continuous and failure-free transmission of electricity. In this paper, the authors present research on a new aluminium-based alloy dedicated for use as a conductive braid in the HTLS cable group. There are many technical solutions for this group of cables on the market, although they are solutions with a number of disadvantages, ranging from their high price, various operational shortcomings, complicated installation techniques, and ending with the risk of monopolistic practices, which is related to the inability to attract several competitive suppliers. The main aim of the research was to develop a new alloy based on aluminium with the addition of silver and molybdenum dedicated for use in special overhead power cables. Experimental research on new materials focused on obtaining the necessary knowledge to produce an overhead wire from these alloys with higher current carrying capacity in relation to the currently used conventional wire materials based on aluminium.

6

Economic assessment of the Northern Copper Belt deposits : a future resource base of copper and silver ores in SW Poland

Bieńko Tomasz, Wierchowiec Jan, Speczik Stanisław

Geological Quarterly

|

2023

|

Vol. 67, No. 3

art. no. 28

EN

Seven undeveloped sediment-hosted stratiform Cu-Ag deposits constitute a future resource base of copper and silver ores in the Fore-Sudetic Monocline in SW Poland. Among these, four have only recently been discovered and documented: Nowa Sól, Sulmierzyce North, Mozów (forming a part of the Northern Copper Belt) and Żary. The three remaining deposits – Bytom Odrzański, Głogów and Retków – surround the currently mined New Copper District to the north-west, north and north-east. Polish Cu-Ag deposits are polymetallic: copper, silver, lead, nickel as well as subordinate rhenium and gold are currently extracted. However, they show high reporting of other by-product metals, such as cobalt, molybdenum, vanadium, zinc and rare earth elements.Unit ore values expressed in US dollars per metric ton of ore have been calculated for deposits in the Northern Copper Belt to compare them with other undeveloped and mined Polish sediment-hosted stratiform Cu-Ag deposits. The calculated unit ore values for the deposits studied are primarily influenced by copper, with a significant contribution (up to 29%) from silver. In terms of base metals other than copper, their contribution to the unit ore values is here relatively low, accounting for only 1–11% of the total value. The proportions of silver and lead in the unit ore value show a trend: they tend to be lower in the vicinity of oxidized fields and gradually increase with distance from these oxidized areas. The share of nickel in the unit ore value, on the other hand, is not influenced by distance from the oxidized fields. Instead, it is dependent on factors such as the thickness and organic content of the shale ore, which affect the accumulation of non-ferrous, redox-sensitive by-product metals, including nickel. Furthermore, we provide a comparative analysis of the total unit ore value among Polish sediment-hosted stratiform Cu-Ag deposits. Particular emphasis is placed on the deposits that constitute the future resource base of copper and silver ores in southwest Poland. A market perspective is drawn to highlight the influence of metal price fluctuations on the unit ore values of the various deposits. By examining the dynamic nature of metal prices, the study offers insights into how changes in market conditions can impact the economic viability of deposits located in different parts of the Fore-Sudetic Monocline. The deposits that constitute the future resource base of copper and silver in Poland show remarkably high copper and silver grades, resulting in significantly higher unit ore values compared to other world-class deposits of different types such as porphyry, epithermal, and IOCG (iron oxide copper gold) deposits.

7

Optymalizacja procesu produkcji koncentratu kolektywnego Zn-Pb o podwyższonej zawartości srebra w procesie flotacji szlamów cynkowych

Cichy Krystian, Skrzypiec Łukasz, Mijał Waldemar, Reguła Cezary, Wójcicki Maciej

Cuprum : czasopismo naukowo-techniczne górnictwa rud

|

2023

|

nr 1-2

15--31

PL

W pierwszej części artykułu przedstawiono schemat technologiczny oraz wyniki badań flotacji szlamów z elektrolizy na nowej linii pilotażowej w ZGH Bolesław S.A., prowadzonych początkowo w kierunku określenia optymalnego uziarnienia nadawy do procesu klasyfikacji, optymalnych parametrów pracy hydrocyklonu oraz wyznaczenia optymalnych warunków flotacji głównych, kontrolnych i czyszczących, w aspekcie określenia optymalnego zestawu odczynników do flotacji. Określono optymalny skład ziarnowy nadawy do procesu klasyfikacji, wyrażony wielkością jednostkowego obciążenia młyna rozmielającego szlamy, wyznaczono optymalne parametry klasyfikacji szlamów w hydrocyklonie, wyrażone wielkością wychodu jego produktu przelewowego, oraz określono optymalne warunki flotacji, dotyczące ilości i rodzaju stosowanych odczynników flotacyjnych. W dalszej części przedstawiono wpływ pozostałych parametrów flotacji na zawartość srebra i jego uzysk w produkowanym koncentracie, takich jak: zagęszczenie nadawy do flotacji, prędkość obwodowa wirników, wielkość dawki głównego zbieracza Selkol w procesach flotacji głównych oraz wielkość pH zawiesiny.

EN

The first part of the paper presents the technological diagram and the results of the flotation process of sludge from electrolysis on a new pilot line at ZGH Boleslaw S.A. initially aimed at determining the optimal grain size distribution of the feed for the classification process, optimal parameters of the hydrocyclone operation and determination of the optimal conditions for main, control and cleaning flotation in terms of determining the optimal set of reagents for flotation. The optimal grain composition of the feed for the classification process was determined, expressed by the unit load of the sludge milling mill, the optimal parameters for sludge classification in the hydrocyclone expressed by the size of its overflow product output were determined, and the optimal flotation conditions for the amount and type of flotation reagents used were determined. The following section presents the effect of other flotation parameters on the content of silver content and its recovery in the concentrate produced, such as: flotation feed compaction, rotor peripheral speed, the size of the main Selkol collector dose in the main flotation processes and the pH of the suspension.

8

Effect of Annealing and Silver Content on the Mechanical Properties of Zn-Al-Ag Alloys

Rubio-Padrón Miguel Angel, Echartea-Reyes Olga Alondra, Calles-Arriaga Carlos A., Rocha-Rangel Enrique

Archives of Metallurgy and Materials

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2023

|

Vol. 68, iss. 4

1467--1471

EN

Through the powder metallurgy technique, alloys of the eutectic composition of the Zn-Al system were manufactured (22.3 wt.%Al), reinforced with Ag additions (0.5, 1, 2.5, 5 wt.%), with subsequent annealing heat treatment at three different temperatures; 100, 150 and 200°C for 1 hr. X-ray diffraction, optical microscopy and mechanical tests were performed on the resulting samples. The addition of Ag favors the formation of alpha and beta compounds with Al and Zn respectively, which improves the compressive strength of the alloy. However, with the presence of Ag the hardness is decreased. On the other hand, the application of an annealing heat treatment, shows no significant effect on the evaluated properties of the alloy. The microstructure of the alloys resulted in the presence of very small grains smaller than 1 mm and with rounded morphology.

9

Wszechstronność zastosowania nanotechnologii w życiu codziennym

Kachel Magdalena

Laboratorium - Przegląd Ogólnopolski

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2022

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nr 4

28--33

PL

Założenia zrównoważonego rozwoju oraz dyscypliny zielonej nanotechnologii to proces dążący do bezpieczeństwa, energooszczędności, redukcji odpadów i zmniejszenia emisji gazów cieplarnianych. Znaczna część nanomateriałów jest przyjazna dla środowiska, a w dziedzinie zielonej nanotechnologii poczyniono widoczne postępy. Nie opracowano do tej pory sposobu zrównoważenia środowiskowego zielonej nanotechnologii, a wszelkie niewiadome muszą zostać przebadane. Przyjmuje się, że nanotechnologia monitoruje wiodący proces kontroli we wszelkich gałęziach produkcji, w tym również rolnictwa, wpływając na poprawę jakości i bezpieczeństwa żywności, zmniejszenie nakładów rolniczych, wzbogacenie wchłaniania składników odżywczych w nanoskali przez rośliny, jak i mikroorganizmy. Rolą nanomateriałów stosowanych w rolnictwie jest więc zmniejszenie ilości rozprowadzanych chemikaliów, zminimalizowanie strat składników odżywczych podczas nawożenia oraz zabezpieczenie plonów przed szkodnikami. Zastosowanie odpowiednich procesów dokarmiania oraz ochrony roślin ma ogromny wpływ na jakość produkowanej żywności. Zastosowanie nanomateriałów/nanocząstek/nanokoloidów w uprawach polowych jest ciągłą niewiadomą zachęcającą naukowców do dalszych badań nad wpływem niniejszych związków na ich rozwój, otrzymywany plon, a w końcowym efekcie - jakość produktów roślinnych.

EN

The field of green nanotechnology pursues the premise of sustainable development in an effort to improve overall balances in terms of safety, energy efficiency, waste production, and greenhouse emissions. Most nanomaterials are environmentally friendly, and the advances made in green nanotechnology in recent years have been substantial. Nonetheless, work on ensuring the environmental sustainability of green nanotechnology is ongoing, with numerous unknowns still requiring scientific determination. It is generally accepted that nanotechnologies have the potential to impact virtually every branch of production, including agriculture, promising e.g. to improve the quality and safety of food, reduce agricultural expenditures, and facilitate better overall nutrient intake by plants and microorganisms. Consequently, agricultural nanomaterials can limit the need for chemical treatment, reduce nutrient losses during fertilization, and help protect plants against pests. The choice of appropriate fertilization and plant protection regimens greatly impacts the resulting quality of the food produced. The viability of many particular nanomaterials/nanoparticles/nanocolloids in field cultivations remains to be determined, which encourages scientists to continue experiments with a view of determining the exact impact of specific compounds on plant growth, yields, and overall quality of the resulting plant products.

10

Srebro i krzem kluczem do rozwoju PV

Bogacz Agnieszka, Wiśniewski Grzegorz, Wiśniewski Konrad, Walczak Agata

Energia i Recykling : gospodarka obiegu zamkniętego

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2022

|

nr 3

PL

Rozwój przemysłu produkcji urządzeń i komponentów dla zeroemisyjnych OZE to podstawa przyszłego bezpieczeństwa surowcowego, technologicznego i energetycznego kraju. W szczególności dotyczy to fotowoltaiki, której rola na rynku energii rośnie i która zwiększa bezpieczeństwo energetyczne oraz środowiskowe, ale ma też potencjał do poprawy bezpieczeństwa surowcowego i technologicznego.

11

Cenne surowce z e-odpadów na wyciągnięcie ręki

Sikorski Wojciech

Energia i Recykling : gospodarka obiegu zamkniętego

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2022

|

nr 4

PL

Obecnie, w dobie ciągłych braków towarów, galopującej inflacji i problemów na różnych szczeblach polityki międzynarodowej, każdy surowiec jest niezwykle cenny. Cóż zatem można powiedzieć o sytuacji, gdy wraz z niektórymi towarami, które straciły już swoją przydatność – najczęściej z uwagi na popsucie się – pozbywamy się pewnych ilości drogocennych substratów tworzących wspomniane dobra? Chodzi tu między innymi o miedź, srebro, złoto, platynę oraz pallad.

12

Silver compounds as minerals in the eastern Karkonosze granitoid pluton, Sudetes, Poland

Kozłowski Andrzej, Matyszczak Witold

Acta Geologica Polonica

|

2022

|

Vol. 72, no. 4

443--468

EN

Twenty silver minerals of the sulphide, arsenide, selenide, telluride, sulphosalt and chloride groups were found in 13 locations in the Variscan Karkonosze granitoid pluton. Previously only one of these minerals was known from this area. The findings include species characterized in publications as rare or exceptionally rare, e.g., muthmannite and tsnigriite. They occur in pegmatites and quartz veins; their parageneses are described. The studies include determination of chemical compositions, formulae calculations and recording of XRD patterns. Inclusion studies in paragenetic quartz indicate that they crystallized from epithermal fluids with a common but low component of CO2. The results suggest that the minerals formed from trace elements (Ag included) in the Karkonosze granitoid due to very local degrees of recrystallization of the host granitoid.

13

Błysk klejnotów zamknięty w pudełeczku kremu

Sikora Magdalena

Przemysł Farmaceutyczny

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2021

|

nr 2

82--86

PL

Złoto, srebro, szlachetne kamienie, do niedawna postrzegane jako nieodłączne elementy biżuterii, coraz częściej można spotkać pośród składników kosmetyków. Nie dziwi to o tyle, że już w papirusach egipskich, pochodzących z około 1600 r. p.n.e., pojawiają się informacje na temat leczniczych i kosmetycznych właściwości tego typu surowców.

14

Influence of silver-containing filler on antibacterial properties of experimental resin composites against Enterococcus faecalis

Adeeb S., Adeeb S., Chladek G., Pakieła W., Mertas A.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

|

Vol. 109, nr 2

59--67

EN

Purpose: The aim of the presented work was to investigate the impact of the S-P introduction into resin-based composites on their effectiveness against Enterococcus faecalis (E. faecalis). Design/methodology/approach: Seven experimental composites based on typical matrix were developed. Six of them contained a filler with antimicrobial properties (silver sodium hydrogen zirconium phosphate, S-P), while the control material contained only common reinforcement fillers. The materials were characterized in terms of the dispersion of the extender in the matrix and then subjected to microbiological tests. The efficiency in the reduction of E. faecalis in the microenvironment was tested. Findings: The composites show a satisfactory distribution of fillers and a high initial reduction of bacteria colonies for the tested strain of E. faecalis. The reduction in bacteria colonies achieved for S-P concentrations from 7% to 13% was similar (median value from 99.8 to 99.9%, when for control material and compound with 1% S-P the number of colonies increased compared to positive control. Research limitations/implications: Laboratory test results may differ from in vivo test performance. In addition, there are many models for conducting laboratory antimicrobial efficacy studies, the results of which are also varied. The cytotoxic tests, long-term investigations and in vivo experiments need to be performed in future experiments. Practical implications: E. faecalis is a Gram-positive bacterium that is commonly detected in persistent endodontic infections and may enter the root canal through the coronal part. Development of composites with antimicrobial properties against this bacterium is as important as obtaining efficacy against cariogenic bacteria. Originality/value: The antimicrobial effectiveness against E. faecalis of experimental composites with submicrometer-sized particles of S-P was not investigated until now.

15

Experimental Study on Dyeing Performance and Antibacterial Activity of Silver Nanoparticle-Immobilized Cotton Woven Fabric

Tania Imana Shahrin, Ali Mohammad, Bhuiyan Riyadh Hossen

Autex Research Journal

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2021

|

Vol. 21, no. 1

45--51

EN

The purposes of the current research were to deposit the silver nanoparticles on the surface of a textile woven fabric and evaluate their dyeing performance and antibacterial activity. The synthesis of silver nanoparticle (Ag°) is done by the in situ method. Strong alkali is used to improve functionality of cellulose before the application of silver nitrate salt (AgNO3). The silver nanoparticle is formed by reduction of ascorbic acid. Various instrumental analyses are done to prove the formation of nanoparticles on the fabric surface. The morphology of nanodeposited fabric is characterized by using scanning electron microscope (SEM), elemental composition is done by energy dispersive spectroscopy, and crystallinity of nanoparticles is obtained by X-ray diffraction (XRD). Nanodeposited fabric is then dyed with direct dyestuff (Direct Red-89). Fourier transform infrared spectroscopy analysis is done to explore the bonding phenomena of un-dyed and dyed fabrics. The dyeing performance and antibacterial activity are examined on the colored fabric to investigate the dyed fabric quality after nanoparticle deposition. Results demonstrate the improvement of 54% of color strength and 11% of dye exhaustion with excellent antibacterial activity.

16

Odzysk srebra z pyłów polerskich przy zastosowaniu wybranych topników

Bałaban Wiktoria, Zgrzędek Patrycja, Matuła Tomasz

Rudy i Metale Nieżelazne Recykling

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2020

|

R. 65, nr 11-12

28--29

PL

Srebro pozyskiwane jest z rud oraz odzyskiwane w procesach recyklingu. Duża zawartość cennego metalu znajduje się w odpadach po obróbce wytworzonych produktów ze srebra. W pracy przedstawiono metodę odzysku srebra z pyłów polerskich poprzez ich przetopienie. Dodanie odpowiedniego topnika gwarantuje większy uzysk srebra podczas procesu. Do badań zastosowano w celu porównania azotan sodu, krzemionkę oraz boraks.

EN

Silver is obtained from ores and recovered in recycling processes. A high content of precious metal is found in the waste from the treatment of silver products. The paper presents a method of silver recovery from polishing dusts by melting them. Adding the appropriate flux guarantees greater silver yield during the process. Sodium nitrate, silica and borax were used for comparison.

17

Determination of the complex refractive index of a subwavelength-diameter spider thread on silver coating by light scattering

Morita Aya, Tajima Fumiaki, Yuji Toshifumi, Mamat Sarizam, Mungkung Narong

Przegląd Elektrotechniczny

|

2020

|

R. 96, nr 9

138--142

EN

In this study, we have created nano-scale silver pipes by sputtering the silver material which frequently shows negative or less-than 1 refractive index onto the spider thread thinner than optical wavelength with. As a part of the study to investigate distribution of the complex refractive index which indicates optical and electromagnetic properties of the resulting silver pipes, we used light scattering method using linearly polarized laser with wavelength of 660 nm and radiated it perpendicularly to the silver pipe to measure the angular distribution of the scattered light intensity. Using the numerical calculation with Coaxial cylinder model based on the values found through preceding studies, we calculated the angular distribution of the scattered light intensity, and fitted the calculation result to the measurement result. This allowed us to determine the complex refractive index and outer diameter of the silver pipe along with the error range. The silver pipe was observed with field emission scanning electron microscope (FE-SEM) and the outer diameter of the silver pipe was estimated. This outer diameter was compared with the outer diameter obtained by fitting the calculation result with the light scattering method to the measurement result to evaluate the validity of the measurement result. This revealed that the result obtained with light scattering method has showed good agreement with that measured using FE-SEM.

PL

W artykule przedstawiono metodę badania nanorurek srebrnych wytwarzanych metodą rozpylania. Do badania właściwości rurek, przede wszystkim ich grubości wykorzystano pomiar światła rozproszonego na długości nici. Do pomiaru wykorzystano światło laserowe o o długości 660 nm. Opracowano model matematyczny metody pomiar współczynnika załamania światła. Dokładność metody potwierdzono wykorzystując mikroskop typu FE-SEM.

18

Plasma deposition of antimicrobial coatings based on silver and copper on polypropylene

Woskowicz Ewa, Łożyńska Monika, Kowalik-Klimczak Anna, Kacprzyńska-Gołacka Joanna, Osuch-Słomka Edyta, Piasek Artur, Gradoń Leon

Polimery

|

2020

|

T. 65, nr 1

33--43

EN

This paper addresses the issue of plasma treatment of the surface of polypropylene (PP) using sputtering of silver (Ag) and copper (Cu) and their oxides with MS-PVD in order to impart antimicrobial activity. It was found that plasma treatment of PP with Cu and Ag based layers allows to provide excellent antimicrobial properties due to a constant release of metal ions. The samples of PP treated with Cu and CuO were characterized by highest antimicrobial properties and stability of the coatings. The most stable and least effective coating against bacteria was Ag-PP sample. In turn, AgO-PP was characterized by the lowest stability in aqueous conditions and strong antimicrobial activity. It was found that leaching of metal ions from the surface of treated PP even in exceptional levels plays a crucial role in bactericidal activity.

PL

Niniejsza praca dotyczy plazmowej obróbki powierzchni polipropylenu (PP) przy użyciu miedzi (Cu) i srebra (Ag) oraz ich tlenków. Powłoki Cu, CuO, Agi AgO, wytworzone na powierzchni PP metodą rozpylania magnetronowego MS-PVD, zbadano pod względem morfologii, składu, stabilności i właściwości antybakteryjnych. Materiały powierzchniowo zmodyfikowane przy użyciu Cu i CuO charakteryzowały się najsilniejszymi właściwościami przeciwbakteryjnymi i najmniejszą stabilnością i trwałością w środowisku wodnym. Powłoka AgO wykazywała najmniejszą stabilność w warunkach wodnych i silną aktywność przeciwbakteryjną, natomiast powłoka Ag wykazywała największą stabilność, a zarazem najsłabsze działanie przeciwbakteryjne. Uzyskane wyniki wskazują, że uwalniane z naniesionych powłok jony, nawet w niewielkim stężeniu, wykazują silne działanie antybakteryjne.

19

Commercial sponges in heterogeneous catalysis: developing novel composites with cobalt and silver

Żółtowska Sonia, Modelska Martyna, Piasecki Adam, Jesionowski Teofil

Physicochemical Problems of Mineral Processing

|

2020

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Vol. 56, iss. 6

89--100

EN

The use of commercial sponges in materials science has gained much recent attention. Their unique properties, namely a fibrous, rigid skeleton, thermal stability and resistance to acid and basic hydrolysis, have been the primary motivation to use them in the development of new composites. In this work, a simple method of immobilization of cobalt and silver cations, followed by their reduction using sodium borohydride, was successfully applied for the first time to obtain functionalized spongin scaffolds. Three different materials, labeled Co_spongin, Ag_spongin and Co-Ag_spongin, were prepared. Their morphological and physicochemical properties were explored using various techniques (SEM+EDS, TG/DTA, FTIR). The focal point of the research was the application of the resulting materials in the reaction of 4-nitrophenol reduction with sodium borohydride in water. It was found that all of the composites possess superior activity in the reduction of 4-nitrophenol, achieving high rate constants of 0.31 min-1 for Ag_spongin, 0.52 min-1 for Co_spongin and 0.86 min-1 for Co-Ag_spongin. Reusability tests showed that all of the composites could be reused five times. Additional structural analysis after catalytic application showed no visible changes in the morphology of the catalysts. The results indicate that spongin can be considered as a facile, cost-effective, renewable and environmentally friendly three-dimensional support for use in heterogeneous catalysis.

20

Analytical expressions for spectral dependences of silver, gold, copper and aluminum dielectric permittivity

Fitio Volodymyr, Yaremchuk Iryna, Vernyhor Oleksandr, Bobitski Yaroslav

Optica Applicata

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2020

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Vol. 50, nr 2

171--184

EN

In this work, the analytical expressions describing experimental data of silver, gold, copper and aluminum dielectric permittivity in a wide spectral range are presented. A comparison of samples production techniques, the measurement methods and the experimental data of different authors led to the conclusion that the most valid data are given by MCPEAK et al. (ACS Photonics 2(3),2015, pp. 326–333) and BABAR et al. (Appl. Opt. 54(3), 2015, pp. 477–481), which are close to each other. Thus, the analytical expressions for silver, gold, copper and aluminum dielectric permittivity spectral dependences are based on it. The spectral range in which the dielectric permittivity is represented by the corresponding analytical expression is divided into several intervals.There is a specific function for each wave length range.