Papers by Keyword: Spectroscopy

Abstract: The primary objectives include investigating the mechanical properties of used construction steel, and evaluating the feasibility of reusing the old materials in green construction projects. The methodology involves gathering samples from demolition sites which are over 40 to 50 years old(1980-1985 construction sites), conducting mechanical testing (such as tensile test and bending test), and performing microstructural analysis.By promoting the utilization of used construction steel, the project seeks to reduce waste, lower material costs, and minimize the environmental impact for sustainable activities. The results we found were that the average maximum load the material can bear was 1.35KN and was bended till 6mm. The average grain size of the material was found to be 20µm. the average elongation percentage came out to be 15.27% and the elements of the material identifies that it is of grade A-36 Steel.Ultimately, this project aspires to facilitate a shift towards more eco-friendly construction practices and supporting the construction industry's transition to sustainable development.

Abstract: The water-in-salt method, recognized for regulating metal ion solvation structure, garners attention in secondary batteries for its potential to broaden the electrolyte's operational range and reduce side reactions. However, the understanding of how anion size variations impact metal ion solvation structure remains limited. This study addresses the gap by employing mixed electrolytes with diverse anion sizes, investigating the effects of electrolyte concentration and anion size on the solvation structure of zinc cations crucial in electrochemical reactions. Various analytical techniques, including FT-IR, Raman, and NMR spectroscopy, are utilized. Mixed electrolytes are formulated by dissolving ZnCl₂ and Zn (NO₃)₂ in water (1.0 mol kg^‒1), with the addition of LiCl and LiNO₃ (0.1 to 19.0 mol kg^‒1). FT-IR and Raman analyses reveal weakened hydrogen bonds with increasing electrolyte concentration. Elevated concentration disrupts bonds between Li⁺ ions and water molecules, resulting in alterations in solvation structure. NMR and FT-IR spectra exhibit distinct behaviors, suggesting influences from molecular bonding structure and anion size, intricately linked to the specific salt used in electrolyte preparation.

Abstract: Graphenic carbon (GC) has been successfully synthesized from biomass (coconut shell charcoal) using the liquid phase exfoliation method. The dopants, in the form of light atoms such as boron (B-GC), were introduced with the aim of improving their magnetic properties. X-ray diffraction was used to identify the GC and B-GC, and the results show broad peaks around 24° and 43°, indicating the presence of graphene-like carbon structure. The bonding structure was also analyzed using X-ray photoelectron (XPS). It reveals the main bonds in GC consist of sp², sp³, and C=O. While the B-GC sample shows an additional bond, namely the B-C bond, as an indicator of the successful doping process of B into the GC structure. Both GC and B-GC show weak room temperature ferromagnetism. Furthermore, these findings show that introducing boron atoms into the graphenic structure can improve magnetization.

Abstract: This study reports on synthesis of ZnO nanostructures using Zinc chloride (ZnCl₂) as precursors and Potassium hydroxide (KOH) as alkaline source in a solvothermal process with varying molar concentrations (Zn²⁺/OH^-) of 1:1, 1:3 and 1:5 for temperatures of 30 °C and 50 °C. The synthesized nanostructures were characterized by X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FT-IR) Spectroscopy, and Ultraviolet Visible (UV-Vis) spectroscopy. ZnO nanostructures synthesized at lower ratios (1:1) exhibited wurtzite hexagonal shapes. However, as the concentration ratios increases in both cases, spherical structures were formed with the emergence of some rod-like structures dominating, and finally aggregated to form flower-like structures at 30 °C temperature. The average crystallite size for nanostructures from XRD (30-50 °C) were in the range 15-21 nm whereas the average particle size from TEM analysis (30-50 °C) were in the range 39-76 nm. Increase in temperature and molar concentration of the alkaline source generally decreased the crystallite and particle size of the as well as a decrease in the wavelength of ZnO nanostructures as a result of blue-shifting of the absorption peak. FT-IR spectra of ZnO NSs prepared from concentration ratios of Zn²⁺: OH^- (1:1, 1:3 and 1:5) at 30 °C and 50 °C showed characteristic peak bands at 461-467 cm^-1 and 460-462 cm^-1 respectively.

Abstract: It is introduced to use a portable spectrometer along with a calibration model for rapid quality control of metakaolin in situ. Verification of the calibration model for predicting the values of two indicators: total acid solubility and mass loss during calcination, indirectly characterizing the pozzolanic activity of metakaolin.

Abstract: Yttrium (III) complexes of Acylaminocarboxylates (N-octanoyl-alaninates, N-octanoyl-phenylalaninate, N-octanoyl-serinates) were prepared by chemical reaction method in methanol solution. The abbreviation of these yttrium (III) complexes were Y(oct-ala)₃, Y(oct-phe)₃ and Y(oct-ser)₃ respectively. These complexes were characterized by elemental analysis, XRD, FT-IR, ¹H NMR, UV-Vis and UV-Vis diffuse reflection. WAXD and SAXS profiles show the amorphous structure of the yttrium complexes. FT-IR and ¹H NMR spectrum establish the molecular formula, functional group information and coordination structure of the yttrium complexes. The optical absorption properties were investigated by UV-Vis and UV-Vis diffuse reflection spectrum.

Abstract: Textile waste is produced in the starch process, a starch removal process, coloring, and printing. The use of banana peel (Musa Paradisiaca) was an alternative that was being developed as an absorbent to remove the color content and metal ions in textile waste. The purpose of this study was to analyze the workings and effectiveness of heavy metal adsorption and textile dyes with banana peel waste. Banana peel particles that were ready to be used as adsorbents were characterized using Scanning Electron Microscopy (SEM) to obtain particle morphology. Absorbance curve of Cu²⁺ dan Cr⁶⁺ can be obtained using spectrophotometric UV-Vis analysis with a wavelength of 635 nm for copper (Cu) and 469 nm for chromium (Cr). The activated carbon of banana peel was applied to 50 ml industrial waste solution and observed changes in absorbance for 120 minutes. The activated carbon was directly in contact with the solution of metal ions but the adsorption power was still not seen effectively so that the Atomic Absorption Spectroscopy (AAS) test was performed. The results of AAS analysis, namely activated carbon can reduce copper and chromium ion content respectively by 55.5% and 61%. If this activated carbon was used as an adsorbent for dyes in textile waste, the average absorption capacity of dye ion was 12.21% during the contact time of adsorption 120 minutes.

Abstract: The work is devoted to studying the polished surface state of K8 optical glass by ellipsometry, IR spectroscopy and surface roughness measurement methods. It is shown that for chemically stable K8 glass the change of the surface state is insignificant, that is caused by its composition.

Abstract: Metal nanoparticles have attracted more and more attention in the last years due to their unique chemical and physical properties which are very different from the metal bulk material. In particular, when the size of nanoparticles decreases below two nm, nanoparticles can be described as nanoclusters (NCs), and they present peculiar optical properties. The excited electrons in addition to specific absorption bands show also a bright luminescence related to the quantum size effect which produce discrete energy levels. Optical properties (absorption and fluorescence) of these NCs are widely used in many different applications in science and engineering, such as chemical sensors, fluorescent probes for bio imaging or in environmental issues. In the present study, we report on the synthesis of silver nanoclusters (AgNCs) in aqueous phase using silver nitrate as precursor salt and L-Glutathione (GSH) as stabilizer. AgNCs were characterized using absorption and fluorescence spectroscopy, and transmission electron microscopy (TEM). The strong absorption and luminescence shown by these NCs are very promising for a possible exploitation both as label for bioimaging and for optical sensors for heavy metal ions.

Abstract: Nanostructured zinc oxide (ZnO) particles were grown on paper substrate made from Abaca hybrid 7 pulp. Microwave irradiation technique was used at power levels (180 and 540W) and exposure times (5, 10, 20 and 25 minutes). Chemical transformations were observed using Fourier Transform Infrared (FTIR) Spectroscopy. The effects of the power levels and exposure times on the morphology of the nanostructures were determined using scanning electron microscopy. FTIR spectra proved the embedment of ZnO on the paper substrate. Power levels and exposure times affected the distribution, particle size and structure of the ZnO nanoparticles. Higher power level and longer exposure resulted to the formation of more ZnO with larger particles. Grainlike and flowerlike ZnO nanostructures were formed at lower and higher levels, respectively.