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1

Functionalization of Gold Nanoparticles for the Detection of Heavy Metals in Contaminated Water Samples in the Province of Tayacaja

Carbajal-Morán Hipólito, Rivera-Esteban Jesús M., Aldama-Reyna Claver W., Mejía-Uriarte Elsi V.

Journal of Ecological Engineering

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2022

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Vol. 23, nr 9

88--99

EN

The work consisted in functionalizing gold nanoparticles to analytically detect heavy metals in contaminated water; in Tayacaja-Huancavelica-Peru, using physical method of laser ablation. The 450 mJ/p Nd:YAG was used as a pulsed laser generator for the production of colloids from AuNPs by the top-down approach; the target was a 1 cm x 1.5 cm high purity gold metallic plate with a thickness of 1 mm, inside a 20 ml cuvette of deionized water, containing 5 ml of L-Cysteine ≥ 75% purity. Nanoparticle colloids were characterized by UV-Vis spectroscopy from 200 to 1160 nm range. Using a convex lens, the gold metal plate was ablated by the laser equipment, located 10 cm from the focus; with λ = 1064 nm and λ = 532 nm with energy equivalent to 60.28 mJ/p and 32.99 mJ/p respectively, with a ratio of 2 Hz, for 30 and 60 min. All the samples produced were subjected to the dispersion process by sonication at 40 KHz for one hour. The functionalized nanoparticles presented a resonance displacement of the maximum wavelength peak with respect to the reference at approximately 22.51 nm; consequently, the increase in diameter occurred at 52.10 nm. The sensitive capacity of the functionalized nanoparticles was verified for different concentrations of analytes in water, made up of divalent heavy metal ions Cd2+, Pb2+, and trivalent nonmetal As3+. At a concentration greater than 500 uM, the color of the functionalized nanoparticles turned bluish, due to the presence of positive ions. Therefore, it was stated that the functionalized nanoparticles enable the detection of heavy metals in water by color variation.

2

Wpływ kształtu impulsu wiązki laserowej na proces spawania laserem impulsowym YAG

Dworak J.

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2012

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R. 56, nr 1

35-40

PL

Przedstawiono ogólną charakterystykę technologii spawania laserowego wiązką promieniowania emitowaną w trybie impulsowym. Wyjaśniono zależności wiążące energetyczne parametry impulsowej wiązki promieniowania. Wskazano na kształt impulsu (określony przebieg zmian mocy w czasie trwania impulsu) jako jeden z parametrów wiązki laserowej mający wpływ na przebieg procesu spawania, szczególnie elementów precyzyjnych o niewielkiej grubości. Za pomocą przykładowych przetopów oraz złączy spawanych wybranych materiałów zilustrowano możliwość zmiany kształtu spoiny oraz sposobu krystalizacji metalu spoiny poprzez zastosowanie impulsów wiązki laserowej o zróżnicowanym kształcie.

EN

It has been presented the general characteristics of laser welding technology with the use of the radiation beam emitted in the pulse mode. It has been explained relationships between energy parameters of pulse radiation beam. It has been shown that the pulse shape (i.e. defined course of power changes during pulse endurance) is one of the laser beam parameters affecting the welding process course, especially that in which thin precise elements are involved. By means of demonstration melting and welded joints of selected materials it has been illustrated the possibility of changing the weld shape and the manner of the weld metal crystallization through the application of different shape laser beam pulses.

3

Twarde powłoki na bazie azotków oraz faz międzymetalicznych wytwarzane laserem impulsowym w aspekcie ich perspektywicznych zastosowań

Major B., Mróz W., Bonarski J., Jelinek M., Lackner J., Waldhauser W.

Inżynieria Materiałowa

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2003

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R. XXIV, nr 6

527-529

PL

Prowadzono badania powłok z faz międzymetalicznych przy ablacji z wykorzystaniem lasera ekscymerowego KrF z tarczy wytworzonych na drodze metalurgicznej z faz typu FeAl i Ni3Al. Powłoki z azotku tytanu wytworzone zostały metodą PLD z zastosowaniem lasera Nd:YAG przy ablacji z tarczy tytanowej w atmosferze azotu oraz nanoszono je na podłoże ze stali ferrytycznej oraz z poliuretanu. Osadzanie prowadzono w położeniu tak prostopadłym do odparowanej na drodze ablacji strugi, jak również równoległym do jej osi. Analizowano morfologię powłoki na mikroskopie SEM oraz AFM. Dokonano pomiarów tekstury oraz wartości naprężeń własnych.

EN

Examinations of intermetallics coatings produced by ablation of the FeAl and Ni3Al targets obtained by conventional metallurgy were performed. Titanium nitride coatings were fabricated by PLD using Nd:YAG laser on both metallic (ferritic steel) and polyurethane substrates by ablation of pure titanium in nitrogen environment. On-axis and off-axis geometry of deposition on metallic substrate was applied. Study of morphology using SEM and AFM was performed. Texture studies as well as residual stresses measurements were carried out.

4

Powłoki nowej generacji wytwarzane na drodze ablacji i osadzania nanosekundowym laserem impulsowym.

Major B., Mróz W., Wierzchoń T.

Inżynieria Materiałowa

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2002

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R. XXIII, nr 5

535-539

PL

Wśród nowoczesnych metod wytwarzania warstw wierzchnich o znaczeniu przyszłościowym, poczesne miejsce zajmuje osadzanie laserem impulsowym. Podstawą metody jest ablacyjne odparowanie tarczy, będące wynikiem bombardowania faz skondensowanych przez jony, elektrony, pojedyncze fotony, pulsujące fotony czyli impulsy laserowe i następnie przeniesienie odparowanej strugi na podłoże. Zachodzi ono poprzez oddziaływanie pomiędzy promieniowaniem laserowym, a odparowaną materią i prowadzi do wzrostu jej energii i rozprzestrzeniania się. Mechanizmy rozpylania laserem impulsowym dzieli się na pierwotne i wtórne, które zostały skrótowo omówione. W pracy przedstawiono najnowsze poglądy na te mechanizmy, a także efekty związane z oddziaływaniem na miarę krótkich i ultrakrótkich impulsów. Zaprezentowano wyniki doświadczalne strukturalnych badań własnych prowadzonych nad warstwami faz międzymetalicznych typu FeAl i Ni3Al osadzanymi laserem ekscymerowym oraz podano dalsze kierunki badań zespołu autorów w zakresie warstw osadzanych metodą PLD.

EN

Among the advanced and perspective methods of fabrication of coatings, one of the most important ones is the pulsed laser deposition (PLD). Evaporation by ablation is the basis of this method which results from the bombardment of condensed phases with irons, electrons, single photons, or pulsed photons, that is, laser pulses. Subsequent transfer of the plume and deposition on the substrate are the next stages of the process. The transport is possible due to the interaction between the laser beam and evaporated species and leads to the energy increase and plume expansion. Mechanisms of pulsed laser sputtering are divided into primary and secondary ones and they are briefly described in the work on the basis of the latest literature together with the description of the interaction between the short and ultrashort pulses and the material. Authors experimental results of structure examinations of coatings fabricated using excimer laser by application of the pulsed laser deposition of the FeAl and Ni3Al intermetallics are presented. A future plan of the authors concerning fabrication of coatings using the PLD method was given.

5

Pulsed laser deposited amorphous magnetic films for strain detection.

Kahlen O., Benziger T., Regener D.

Inżynieria Materiałowa

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2001

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R. XXII, nr 4

423-425

EN

Amorphous magnetic Fe-B-Si films have been produced by means of KrF laser ablation of Fe78B13Si9 amorphous magnetic ribbons. Laser fluence, repetition rate and the number of pulses were the variable parameters. TEM and AFM investigations of the deposited films exhibited a hetero-amorphous structure with dimensions in the 4-6 nm range. Physical parameters, such as the Curie temperature value and electrical resistance were comparable to those of the initial ribbon target material. Strain dependent eddy current measurements revealed a linear and very high signal response to applied strains, showing the films potential for a variety of applications until now performed by strain gauges.

6

Nanomateriały osadzane laserem impulsowym - technika PLD

Major B., Ebner R.

Krzepnięcie Metali i Stopów

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2000

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R. 2, nr 42

205--215

EN

Application of ablation and deposition of the plume is a method to produce nanomaterials. At present, it is intensivelly studied due to possibility of deposition of various materials. Flexability of the method and transfer of stoichiometry as well as possibility to influence the plume by atmosphere in the reactive chamber makes this method very useful. Limitation is connected with the equipment comprising a laser working in the range of UV wavelenghts in the regime of nano-seconds pulses. Excimer lasers or Nd:Y AG lasers with Q-switch are used in the pulse laser deposition techniques (PLD). Nanostructures produced using Nd:YAG laser of metallic titanium, titanium nitride, titanium oxide were under examination. XRD and electron diffraction were applied to identify the formed phases in the deposited layers. Microstructure on the surface and on the crosss sections was examined by means of SEM and TEM. Residual stresses and texture in the layers were measured using XRD methods.

7

Zjawisko generacji drugiej harmonicznej światła i możliwość jego obserwacji.

Golis E.P.

Szkło i Ceramika

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1999

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R. 50, nr 2

31-33

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Microstructure of pulsed laser deposited Ti, TiN and TiO thin layers.

Major B., Ebner R., Kusiński J., Wołczyński W., Morgiel J., Maziarz W.

Inżynieria Materiałowa

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1998

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R. XIX, nr 4

1057-1060

EN

Complex structural examinations were performed on thin layers of Ti, TiN and TiO obtained by means of pulsed laser deposition (PLD). Influence of deposition parameters on the film morphology was under examination. The received films revealed an uniform nanostructure. Appearance of a tetragonal Ti-phase was stated in the deposited Ti layers in argon atmosphere. The TiN-phase was formed independently of the nitrogen flow. By increasing concentration of oxygen in the chamber, transition of oxides from Ti2O via TiO to TiO2 was observed. TEM examination of cross-sections of Ti layers revealed a micro-collumnar structure as well as verified the existence of the tetragonal phase. The deposited TiO layer was characterized by a {001} texture.