Depth-resolved infrared microscopy and UV-VIS spectroscopy analysis of an artificially degraded polyester-urethane clearcoat

2014 ◽  
Vol 110 ◽  
pp. 422-434 ◽  
Author(s):  
Koen N.S. Adema ◽  
Hesam Makki ◽  
Elias A.J.F. Peters ◽  
Jozua Laven ◽  
Leendert G.J. van der Ven ◽  
...  
2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Emilia Tomaszewska ◽  
Katarzyna Soliwoda ◽  
Kinga Kadziola ◽  
Beata Tkacz-Szczesna ◽  
Grzegorz Celichowski ◽  
...  

Dynamic light scattering is a method that depends on the interaction of light with particles. This method can be used for measurements of narrow particle size distributions especially in the range of 2–500 nm. Sample polydispersity can distort the results, and we could not see the real populations of particles because big particles presented in the sample can screen smaller ones. Although the theory and mathematical basics of DLS technique are already well known, little has been done to determine its limits experimentally. The size and size distribution of artificially prepared polydisperse silver nanoparticles (NPs) colloids were studied using dynamic light scattering (DLS) and ultraviolet-visible (UV-Vis) spectroscopy. Polydisperse colloids were prepared based on the mixture of chemically synthesized monodisperse colloids well characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM), DLS, and UV-Vis spectroscopy. Analysis of the DLS results obtained for polydisperse colloids reveals that several percent of the volume content of bigger NPs could screen completely the presence of smaller ones. The presented results could be extremely important from nanoparticles metrology point of view and should help to understand experimental data especially for the one who works with DLS and/or UV-Vis only.


Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 867 ◽  
Author(s):  
Cataldo Arcuri ◽  
Lorenzo Monarca ◽  
Francesco Ragonese ◽  
Carmen Mecca ◽  
Stefano Bruscoli ◽  
...  

The synthesis of ultrasmall UiO-66 nanoparticles (NPs) with an average size of 25 nm, determined by X-ray powder diffraction and electron microscopies analysis, is reported. The NPs were stabilized in water by dialyzing the NP from the DMF used for the synthesis. DLS measurements confirmed the presence of particles of 100 nm, which are spherical aggregates of smaller particles of 20–30 nm size. The NP have a BET surface area of 700 m2/g with an external surface area of 300 m2/g. UiO-66_N (UiO-66 nanoparticles) were loaded with acridine orange as fluorescent probe. UV-vis spectroscopy analysis revealed no acridine loss after 48 h of agitation in simulated body fluid. The biocompatibility of UiO-66_N was evaluated in human glioblastoma (GBM) cell line U251, the most malignant (IV grade of WHO classification) among brain tumors. In U251 cells, UiO-66_N are inert since they do not alter the cell cycle, the viability, migration properties, and the expression of kinases involved in cancer cell growth. The internalization process was evident after a few hours of incubation. After 24 h, UiO-66_N@Acr (UiO-66_N loaded with acridine orange) were detectable around the nuclei of the cells. These data suggest that small UiO-66 are biocompatible NP and could represent a potential carrier for drug delivery in glioblastoma therapies.


Processes ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 2235
Author(s):  
Makhmut Yakubov ◽  
Guzalia Abilova ◽  
Elvira Tazeeva ◽  
Svetlana Yakubova ◽  
Damir Tazeev ◽  
...  

The composition of purified vanadyl porphyrins recovered from the resins of heavy oils possessing high and low vanadium contents was investigated. Vanadium content in the resins of the heavy oils under study differs by a factor of ca. 15. To recover and purify vanadyl porphyrins from the resins, extraction by N,N–dimethylformamide (DMF) with subsequent two-stage column chromatography on silica gel and sulfocationite were employed. The change of structural-group composition and content of vanadyl porphyrins in the products obtained at each stage was evaluated using Fourier IR and UV-Vis spectroscopy. Analysis of the purified vanadyl porphyrins using MALDI mass spectrometry determined distribution of their most abundant types (etio- and DPEP) and identified C27–C39 homologs for the resins possessing high vanadium content and C28–C39 homologs for the resins with low vanadium content.


2016 ◽  
Vol 15 (05n06) ◽  
pp. 1660015 ◽  
Author(s):  
M. Krishnaprabha ◽  
Manjunatha Pattabi

This report presents the easily reproducible biosynthesis of gold nanoparticles (AuNPs) at room temperature with extract prepared using three year old dried Garcinia Indica (GI) fruit rind. Due to the presence of two major bioactive compounds garcinol and hydroxy citric acid, rinds of GI fruit exhibit anti-cancer and anti-obesity properties. The quantity of fruit rind extract directed the morphology of the as synthesized particles. The nucleation and growth of AuNPs and catalytic activity are studied using UV-Vis spectroscopy. The crystalline nature of biosynthesized AuNPs is corroborated by X-ray Diffraction techniques. The morphology is studied using field emission scanning electron microscopy (FESEM). Fourier transform infra-red (FTIR) spectroscopy analysis revealed that biomolecules were involved in the synthesis and capping of AuNPs. As the Fermi potential of noble metal NPs becomes more negative, they are used in various electron transfer processes. The AuNPs produced using GI extract showed excellent catalytic activity when used as a catalyst in the reduction of well-known toxic pollutant 4-Nitrophenol (4-NP) to 4-Aminophenol (4-AP) in the presence of excess sodium borohydride.


2021 ◽  
Author(s):  
Divya S. Parimi ◽  
Chandra S. Bhatt ◽  
Tharun K. Bollu ◽  
Madhura H. U ◽  
Noah Jacob ◽  
...  

Fish scale waste-derived highly transparent biotemplate is pioneered as an economical and sustainable alternative to replace plastic cuvettes for ultralow-volume and highly sensitive UV-Vis spectroscopy analysis.


Author(s):  
Nguyen Hoc Thang ◽  
Nguyen Thuc Boi Huyen

In the 21st century, mankind has witnessed the rapidly development of all industries with a lot of new products in a variety of types and designs. However, this development has been also causing many problems with the society and the ecological environment such as a wasteful excess of products, exhaustive exploitation of natural resources, indiscriminate deforestation, and waste pollution affecting the living environment, ecosystem, and human health. Many organizations and governments are calling for environmental protection, limit waste emissions, and find good solutions to use the recycled materials as raw materials in production plants. This study would like to provide a solution which not only utilizes waste packaging Pinaceae wood for recycling as raw material but also supplies to the market with a green product responding to the durability requirements in fact. Pinaceae wood packaging residues were chemically processed through two stages. The amount of lignin extract from Pinaceae was determined by the method of Tappi 222 om-02 which was significantly influenced by the extraction parameters such as temperature, time and concentration of the treatment solution. Morphological modification of wood materials was analyzed by SEM micrographs. In particular, the mechanical properties of the Epoxy/TPW2 composite green material have been significantly improved with increasing up to 206–540 % compared to the original Pinaceae wood. The optical properties of the wood have completely changed from opaque pine wood with the optical transmittance of 8 % into transparent composite material with the optical transmittance up to 85 % using UV-vis spectroscopy analysis.


2009 ◽  
Vol 1242 ◽  
Author(s):  
Raúl J. Delgado-Macuil ◽  
Marlon Rojas-López ◽  
Valentín L. Gayou ◽  
Abdu Orduña-Díaz ◽  
Joel Díaz-Reyes ◽  
...  

ABSTRACTIn this work we used the Fourier Transform Infrared spectroscopy and UV/Vis spectroscopy to analyze the behaviour of self-ensemble films of spiropyran when the films were irradiated by UV. In UV/Vis spectroscopy is possible observe the generation of the absorption peak, at 575 nm, associated to the merocyanine state when the ring-opening process is induced by UV light. In ATR the kinetics of the ring-opening was determinate too; following the spectra changes in real time.


2018 ◽  
Vol 80 (6) ◽  
Author(s):  
Nur Shaheera Hussain ◽  
Noor Aniza Harun ◽  
Mohd Naim Fadhli Mohd Radzi ◽  
Izwandy Idris ◽  
Wan Iryani Wan Ismail

Silver nanoparticles (AgNPs) offer a broad range of high commercial value applications. However, current techniques to synthesize AgNPs using chemical and physical approaches are toxic to the environment and not cost-effective in the long-term. Therefore, utilization of green biological synthesis technique to produce AgNPs is one of the solutions. In this study, marine polychaete Diopatra claparedii was used to investigate its potential in synthesizing AgNPs. Specimens were collected from tidal flats adjacent to the mangrove forest in the west coast of Peninsular Malaysia and divided into two groups: freshly prepared (acclimatized in aquaria) and frozen (kept in the freezer) samples. Samples from both groups were cut, finely pulverized, filtrated, and mixed with silver nitrate (AgNO3) at room temperature. Colour changes were recorded after 24 hours, 2 weeks, and 8 weeks of incubation. Formation of AgNPs was quantified using UV-Vis spectroscopy analysis, where surface Plasmon resonance (SPR) peaks were observed in the range of 400–440 nm, confirming the formation of the AgNPs. Subsequently, the synthesized nanoparticles were validated using scanning electron microscope. AgNPs showed weak antibacterial activity because of aggregation. Further studies are required to confirm the findings.


Sign in / Sign up

Export Citation Format

Share Document