53 research outputs found
Spectral Engineering via Complex Patterns of Circular Nano-object Miniarrays: I. Convex Patterns Tunable by Integrated Lithography Realized by Circularly Polarized Light
Illumination of colloid sphere monolayers by circularly polarized beams enables the fabrication of concave patterns composed of circular nanohole miniarrays that can be transferred into convex metal nano-object patterns via a lift-off procedure. Unique spectral and near-field properties are achievable by controlling the geometry of the central nanoring and quadrumer of slightly rotated satellite nanocrescents and by selecting those azimuthal orientations that promote localized plasmon resonances. The spectral and near-field effects of hexagonal patterns composed of uniform gold nanorings and nanocrescents, which can be prepared by transferring masks fabricated by a perpendicularly and obliquely incident single homogeneous circularly polarized beam, were studied to uncover the supported localized plasmonic modes. Artificial rectangular patterns composed of a singlet nanoring and singlet nanocrescent as well as quadrumer of four nanocrescents were investigated to analyze the effect of nano-object interactions and lattice type. It was proven that all nanophotonical phenomena are governed by the azimuthal orientation independent localized resonance on the nanorings and by the C2, C1, and U resonances on the nanocrescents in case of (E) over bar -field direction perpendicular and parallel to their symmetry axes. The interaction between localized surface plasmon resonances on individual nano-objects is weak, whereas scattered photonic modes have a perturbative role at the Rayleigh anomaly only on the larger periodic rectangular pattern of miniarrays. Considerable fluorescence enhancement of dipolar emitters is achievable at spectral locations promoting the C and U resonances on the constituent nano-object
Artificial Intelligence-based Prediction of In Vitro Dissolution Profile of Immediate Release Tablets with Near-infrared and Raman Spectroscopy
The objective of the present work was to develop an artificial neural network (ANN) model to accurately predict the dissolution profile of immediate release tablets based on non-destructive spectral data. Six different tablet formulations with varying API (caffeine) and disintegrant (potato starch) concentrations were prepared. The near-infrared (NIR) and Raman spectra of each tablet were collected in both reflection and transmission modes, then principal component analysis (PCA) was conducted. The training of the ANN was performed at each hidden neuron number from 1 to 10 in order to determine the optimal number of neurons in the hidden layer. The best results were obtained when a small number of neurons (1–3) was used. In the case of all four spectroscopic methods, the average similarity values (f2) of the optimized ANN models were above 59 for the validation tablets, indicating that the predicted dissolution profiles were similar to the measured dissolution curves. The optimized model based on reflection Raman spectra exhibited the best predictive ability. The results demonstrated the potential of ANN models in the implementation of the real-time release testing of tablet dissolution
Synthesis of Novel Aromatic Core Zero Generation Dendrimers
Bromomethyl arenes used as polyfunctional core of dendrimers were derivatized with diethanolamine branches. The obtained compounds containing 4 or 6 hydroxyl terminal surface groups are highly water-soluble
Gyógyszernyomok eltávolítása tisztított szennyvizekből nagyhatékonyságú oxidációs eljárásokkal = Removal of trace pharmacuticals form clarified wastewaters by Advanced Oxidation Processes
A projekt megvalósítása során olyan nagyhatékonyságú oxidációs eljárásokon (AOP) alapuló vízkezelési eljárásokat dolgoztunk ki, amelyek alkalmasak biológiailag kezelt szennyvizekben nagyon kicsiny koncentrációban visszamaradó gyógyszernyomok és bomlástermékeik költséghatékony és eredményes eltávolítására. A munkához kellő megbízhatóságú és kimutatási képességű analitikai módszereket fejlesztettünk ki és adaptáltunk. Modellvegyületként ibuprofent, ketoprofent, diklofenakot, naproxent választottunk, de vizsgáltunk antibiotikumot (perfloxacint) is. Az ózon és UV sugárzás kombinációján alapuló módszer jól használható és kellően költség-hatékony az egyszerűen és gazdaságosan üzemeltethető olyan kisnyomású higanygőz-lámpára alapozva, amelynek az ózont termelő 185 nm-es komponensét is hasznosítani tudjuk. Megvizsgáltuk továbbá a vákuum-ultraibolya (VUV) fotolízis és a heterogén fotokatalízis alkalmazhatóságát is. A munkából 12 rangos nemzetközi folyóiratban megjelent dolgozat született (összesített impakt faktor 42,9), 37 előadás hangzott el nemzetközi és hazai konferenciákon, Szabó Rita elkészítette doktori (PhD) dolgozatát, valamint több diplomadolgozat és diákköri dolgozat is készült a tématerületen. | In this project a new wastewater treatment method was developed, based on a novel concept to eliminate toxic organic contaminants of pharmaceutical origin in wastewater effluents and which operates on the principle of combined innovative application of a range of advanced oxidation processes (AOPs). For the reaction kinetic measurements analytical methods with good accuracy, correctness and an unusually low detection limit were developed and adapted, which enables to analyze the components with ppb concentrations. The chosen pharmaceutical compounds were; ketoprofen, ibuprofen, diclophenac, naproxen and one of the antibiotics, the perfloxacin. The combination of ozone and UV-radiation treatment method proved to be the most promising both in terms of cost efficiency and effectiveness. A specific low pressure mercury vapour lamp equipped with a VUV transparent quartz sleeve (transparent to the ozone producing 185 nm component of the light source) was applied. VUV photolysis and heterogeneous photocatalysis also were used in order to compare the applicability of various methods based on the generation of reactive free-radicals. During the elaboration of this project, 12 papers were published (their summarized impact factor is 42.9), 37 conference presentation were held on international and national conferences. Rita Szabó prepared her PhD thesis in this topic and numerous diploma theses were prepared by students worked in this project
- …