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Digital Mammograms with Image Enhancement Techniques for Breast Cancer Detection: A Systematic Review

Suradi SH, Abdullah KA

Curr Med Imaging, 2021 Jan 26.
PMID: 33504312 DOI: 10.2174/1573405617666210127101101

BACKGROUND: Digital mammograms with appropriate image enhancement techniques will improve breast cancer detection, and thus increase the survival rates. The objectives of this study were to systematically review and compare various image enhancement techniques in digital mammograms for breast cancer detection.
METHODS: A literature search was conducted with the use of three online databases namely, Web of Science, Scopus, and ScienceDirect. Developed keywords strategy was used to include only the relevant articles. A Population Intervention Comparison Outcomes (PICO) strategy was used to develop the inclusion and exclusion criteria. Image quality was analyzed quantitatively based on peak signal-noise-ratio (PSNR), Mean Squared Error (MSE), Absolute Mean Brightness Error (AMBE), Entropy, and Contrast Improvement Index (CII) values.
RESULTS: Nine studies with four types of image enhancement techniques were included in this study. Two studies used histogram-based, three studies used frequency-based, one study used fuzzy-based and three studies used filter-based. All studies reported PSNR values whilst only four studies reported MSE, AMBE, Entropy and CII values. Filter-based was the highest PSNR values of 78.93, among other types. For MSE, AMBE, Entropy, and CII values, the highest were frequency-based (7.79), fuzzy-based (93.76), filter-based (7.92), and frequency-based (6.54) respectively.
CONCLUSION: In summary, image quality for each image enhancement technique is varied, especially for breast cancer detection. In this study, the frequency-based of Fast Discrete Curvelet Transform (FDCT) via the UnequiSpaced Fast Fourier Transform (USFFT) shows the most superior among other image enhancement techniques.

Matched MeSH terms: Fourier Analysis
Fulltext Dataset of Fourier transform-infrared coupled with chemometric analysis used to distinguish accessions of Garcinia mangostana L. in Peninsular Malaysia

Samsir SA, Bunawan H, Yen CC, Noor NM

Data Brief, 2016 Sep;8:1-5.
PMID: 27257614 DOI: 10.1016/j.dib.2016.04.062

In this dataset, we distinguish 15 accessions of Garcinia mangostana from Peninsular Malaysia using Fourier transform-infrared spectroscopy coupled with chemometric analysis. We found that the position and intensity of characteristic peaks at 3600-3100 cm(-) (1) in IR spectra allowed discrimination of G. mangostana from different locations. Further principal component analysis (PCA) of all the accessions suggests the two main clusters were formed: samples from Johor, Melaka, and Negeri Sembilan (South) were clustered together in one group while samples from Perak, Kedah, Penang, Selangor, Kelantan, and Terengganu (North and East Coast) were in another clustered group.

Matched MeSH terms: Fourier Analysis
Fulltext Experimental and DFT data of p-chlorocalix[4]arene as drugs receptor

Kadir MA, Abdul Razak FI, Haris NSH

Data Brief, 2020 Oct;32:106263.
PMID: 32905010 DOI: 10.1016/j.dib.2020.106263

The data in this article provide information on spectroscopic and theoretical data for p-chlorocalix[4]arene when combined with selected drugs, such as paracetamol, ibuprofen, and cetirizine. The present spectroscopic data are generated from Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (1H NMR and 13C NMR), and Ultraviolet-Visible spectroscopy (UV-Vis) as the key tools for molecular characterization. The measurement of the optimization energy, interaction energy, and the band gap energy between the molecules was calculated by Gaussian 09 software. It is interesting to note that of the three titled drugs identified, p-chlorocalix[4]arene showed the highest interaction energy with paracetamol, followed by ibuprofen and cetirizine.

Matched MeSH terms: Fourier Analysis
Fulltext Dataset in characterization of the polymer produced using different method of synthesis polychloromethylstyrene (PCMS) with clay and without clay

Ismail N, Nazri NK, Abdullah AA, Wan Nik WMN, Wright LJ

Data Brief, 2021 Feb;34:106738.
PMID: 33521179 DOI: 10.1016/j.dib.2021.106738

Polychloropolymethylstyrene (PCMS) polymers were synthesized with clay Cloisite and without clay Cloisite and chloromethylstyrene (CMS) combine with styrene (1:1) v/v or known as copolymer and clay Cloisite by the polymerization process. The attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra of each polymer synthesized are reported. The spectra of IR shows the different value of the wavenumber and intensity for each set of different sample. The spectra can be as a reference for others to use in synthesizing this polymer and clay Cloisite for different type of application.

Matched MeSH terms: Fourier Analysis
Fulltext Data on Fourier transform-infrared of Cosmos caudatus Kunth. tissues analyzed with chemometric analysis

Gunasekaran D, Bunawan H, Ismail I, Noor NM

Data Brief, 2018 Aug;19:1423-1427.
PMID: 30229014 DOI: 10.1016/j.dib.2018.06.025

In this dataset, we differentiate four different tissues of Cosmos caudatus Kunth (leaves, flowers, stem and root) obtained from UKM Bangi plot, based on Fourier transform-infrared spectroscopy. Different tissues of C. caudatus demonstrated the position and intensity of characteristic peaks at 4000-450 cm-1. Principal component analysis (PCA) shows three main groups were formed. The samples from leaves and flowers were found to be clustered together in one group, while the samples from stems and roots were clustered into two separate groups, respectively. This data provides an insight into the fingerprint identification and distribution of metabolites in the different organs of this species.

Matched MeSH terms: Fourier Analysis
Fulltext Chemical and antibacterial data of synthesized thioureido derivatives

Kadir MA, Ramli R, Yusof MSM, Ismail N, Ngah N, Haris NSH

Data Brief, 2019 Dec;27:104651.
PMID: 31700958 DOI: 10.1016/j.dib.2019.104651

This paper provided comprehensive data on spectroscopic and antibacterial activities of thioureido compounds which are relevant with research article entitled "Synthesis, Spectroscopic Studies and Antibacterial Activity of New Lauroyl Thiourea Amino Acid Derivatives" [1]. Based on the reported study, four new thioureido derivatives, namely 3-(3-dodecanoyl-thioureido)propionic acid (R1), 2-(3-dodecanoyl-thioureido)-3-methyl butyric acid (R2), (3-dodecanoyl-thioureido)acetic acid (R3) and 2-(3-dodecanoyl-thioureido)-3-phenyl propionic acid (R4) were characterized by elemental analysis, Fourier Transform Infrared (FTIR), 1H Nuclear Magnetic Resonance (1H NMR) and 13C Nuclear Magnetic Resonance (13C NMR), and Ultraviolet Visible spectroscopy (UV-Vis). The preliminary results from antibacterial assay which were tested against Gram-positive bacteria such as Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus aureus and Gram-negative bacteria such as Escherichia coli, Salmonella typhimurium are also described.

Matched MeSH terms: Fourier Analysis
Correlation data of (Z)-1-[4-(trifluoromethyl)benzylidene]thiosemicarbazide via spectroscopic methods and Density Functional Theory studies

Osman UM, Farizal ASN, Kadir MA, Razali MH, Rozaini MZH, Arshad S

Data Brief, 2019 Dec;27:104673.
PMID: 31720328 DOI: 10.1016/j.dib.2019.104673

New compound, namely (Z)-1-[4-(trifluoromethyl)benzylidene]thiosemicarbazide was successfully synthesized using thiosemicarbazide with 4-(trifluoromethyl)-benzaldehyde in ethanol solution. The data presented in this articles is related to our research articles entitled "Crystal Structure of (Z)-1-[4-(Trifluoromethyl)benzylidene]thiosemicarbazide" (Osman et al., 2017) [1]. This work shows the continue data from experimental spectroscopic measurement which are Fourier Transform Infrared (FTIR) and 13C Nuclear Magnetic Resonance (13C NMR). Assessment on the correlation with theoretical computational data was also carried out through GaussView 5.0.9 and Gaussian09 software. Molecular Electrostatic Potential (MEP) and Highest Occupied Molecular Orbital-Lowest Unoccupied Molecular Orbital (HOMO-LUMO) were also illustrated.

Matched MeSH terms: Fourier Analysis
Fulltext Computational analysis of fluid flow past a bluff body at low Reynolds number in different apex angle

Jusoh, M.Z.M., Nur Ain, A.R, Muhammad Wafi Md Nor

ESTEEM Academic Journal, 2020;16(2):65-74.
MyJurnal

A computational fluid dynamic analysis (CFD) is presented in the study of low Reynolds number fluid flow moving past bluff bodies. The study is focusing on the understanding of the effects of the apex-angles orientation on the flow structure and related occurring force. The apex-angle both facing upstream and downstream were computationally investigated. The simulation results of the cylinder solid are compared with available experimental data to justify the results and the model used. Results obtained in the present work were Strouhal number, drag coefficient, and Fast Fourier Transform (FFT). The study had found that the value of the drag force is increasing directly proportional to the apex angle. In contrast, the value of Strouhal number inversely proportional to the increasing of the apex angle. This was due to the flow over a cylinder creating a vortex shedding in the wake region which influenced the flow separation of fluid. Through the changing on orientation of the apex angle, it was also found that the characteristic linear dimension of the geometry will also be changed, thus affecting the flow pattern.

Matched MeSH terms: Fourier Analysis
In vitro assessment on effect of duodenal contents on the lead (Pb(2+)) binding capacity of two probiotic bacterial strains

Xing S, Song Y, Liang JB, Faseleh Jahromi M, Shokryazda P, Mi J, et al.

Ecotoxicol Environ Saf, 2017 May;139:78-82.
PMID: 28113114 DOI: 10.1016/j.ecoenv.2017.01.016

In vitro Lead (Pb(2+)) binding capacity of two probiotic bacteria strains, namely Bifidobacterium longumBB79 and Lactobacillus pentosusITA23, was assessed following incubation with the intestinal contents (IC) of laying hens. Results of this study demonstrated that IC treatment significantly enhanced (P<0.01) Pb(2+) binding capacity of both bacterial strains. Fourier transform infrared analysis indicated that several functional groups (O-H or N-H, C-H, C˭O, C-O, and C-O-C) on the bacteria cell wall involved in metal ion binding were altered after IC incubation, and new groups appeared between the 3700cm(-1) and 4000cm(-1)bands. Transmission electron microscopy demonstrated that after incubation with IC, unidentified IC components created new binding sites on the bacterial cell surface. These particles also changed the mechanism of Pb(2+) binding of the two strains from intracellular accumulation to extracellular adsorption.

Matched MeSH terms: Fourier Analysis
Status, source identification, and health risks of potentially toxic element concentrations in road dust in a medium-sized city in a developing country

Praveena SM, Aris AZ

Environ Geochem Health, 2018 Apr;40(2):749-762.
PMID: 28929262 DOI: 10.1007/s10653-017-0021-8

This study aims to determine the status of potentially toxic element concentrations of road dust in a medium-sized city (Rawang, Malaysia). This study adopts source identification via enrichment factor, Pearson correlation analysis, and Fourier spectral analysis to identify sources of potentially toxic element concentrations in road dust in Rawang City, Malaysia. Health risk assessment was conducted to determine potential health risks (carcinogenic and non-carcinogenic risks) among adults and children via multiple pathways (i.e., ingestion, dermal contact, and inhalation). Mean of potentially toxic element concentrations were found in the order of Pb > Zn > Cr(IV) > Cu > Ni > Cd > As > Co. Source identification revealed that Cu, Cd, Pb, Zn, Ni, and Cr(IV) are associated with anthropogenic sources in industrial and highly populated areas in northern and southern Rawang, cement factories in southern Rawang, as well as the rapid development and population growth in northwestern Rawang, which have resulted in high traffic congestion. Cobalt, Fe, and As are related to geological background and lithologies in Rawang. Pathway orders for both carcinogenic and non-carcinogenic risks are ingestion, dermal contact, and inhalation, involving adults and children. Non-carcinogenic health risks in adults were attributed to Cr(IV), Pb, and Cd, whereas Cu, Cd, Cr(IV), Pb, and Zn were found to have non-carcinogenic health risks for children. Cd, Cr(IV), Pb, and As may induce carcinogenic risks in adults and children, and the total lifetime cancer risk values exceeded incremental lifetime.

Matched MeSH terms: Fourier Analysis
Synthesis and characterization of anthill-eggshell composite adsorbent for removal of hexavalent chromium from aqueous solution

Yusuff AS, Gbadamosi AO, Lala MA, Ngochindo JF

Environ Sci Pollut Res Int, 2018 Jul;25(19):19143-19154.
PMID: 29725925 DOI: 10.1007/s11356-018-2075-2

In this study, adsorption behavior of anthill-eggshell composite (AEC) for the removal of hexavalent chromium (Cr6+) from aqueous solution was investigated. The raw AEC sample was thermally treated at 864 °C for 4 h and characterized using Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and X-ray fluorescence (XRF) techniques. The effects of adsorption process variables including initial Cr6+ concentration, contact time, and adsorbent dosage on the Cr6+ removal efficiency were investigated using central composite design (CCD) of response surface methodology (RSM). Equilibrium adsorption isotherm and kinetic were also studied. From the analysis of variance (ANOVA), the three variables proved to be significant and the optimum conditions for Cr6+ adsorption were obtained to be 150 mg/L initial Cr6+ concentration, 45.04-min contact time, and 0.5 g adsorbent dosage, which resulted in 86.21% of Cr6+ adsorbed. Equilibrium isotherm study showed that Freundlich model fitted well to the experimental data. The pseudo-second-order kinetic model appeared to better describe the experimental data. The study showed that mixed anthill-eggshell is a promising adsorbent for removing Cr6+ from aqueous solution.

Matched MeSH terms: Fourier Analysis
Taguchi design-assisted immobilization of Candida rugosa lipase onto a ternary alginate/nanocellulose/montmorillonite composite: Physicochemical characterization, thermal stability and reusability studies

Mohd Hussin FNN, Attan N, Wahab RA

Enzyme Microb Technol, 2020 May;136:109506.
PMID: 32331714 DOI: 10.1016/j.enzmictec.2019.109506

Biomass from oil palm frond leaves (OPFL) is an excellent reservoir of lignocellulosic material which full potential remains untapped. This study aimed to statistically optimize the covalent immobilization of Candida rugosa lipase (CRL) onto a ternary support comprised of OPFL derived nanocellulose (NC) and montmorillonite (MMT) in alginate (ALG) (CRL-ALG/NC/MMT). The coarser topology and the presence of characteristic spherical globules in the field emission scanning electron micrographs and atomic force micrographs, respectively, supported the existence of CRL on ALG/NC/MMT. In addition, amide peaks at 3478 and 1640 cm-1 in the fourier transform infrared spectra affirmed that CRL was covalently bonded to ALG/NC/MMT. The optimized Taguchi Design-assisted immobilization of CRL onto ALG/NC/MMT (7 h of immobilization, 35℃, pH 5, 7 mg/mL protein loading) gave a production yield of 92.89 % of ethyl levulinate (EL), as proven by gas chromatography-mass spectrometric ([M] +m/z 144, C7H12O3), FTIR and nuclear magnetic resonance (CAS-539-88-8) data. A higher optimal reaction temperature (50℃) and the reusability of CRL-ALG/NC/MMT for up to 9 esterification cycles substantiated the appreciable structural rigidification of the biocatalyst by ALG/NC/MMT, which improved the catalytic activity and thermal stability of the lipase.

Matched MeSH terms: Fourier Analysis
The use of Fourier transform mid infrared (FT-MIR) spectroscopy for detection and quantification of adulteration in virgin coconut oil

Rohman A, Che Man YB

Food Chem, 2011 Nov 15;129(2):583-588.
PMID: 30634271 DOI: 10.1016/j.foodchem.2011.04.070

Currently, the authentication of virgin coconut oil (VCO) has become very important due to the possible adulteration of VCO with cheaper plant oils such as corn (CO) and sunflower (SFO) oils. Methods involving Fourier transform mid infrared (FT-MIR) spectroscopy combined with chemometrics techniques (partial least square (PLS) and discriminant analysis (DA)) were developed for quantification and classification of CO and SFO in VCO. MIR spectra of oil samples were recorded at frequency regions of 4000-650cm-1 on horizontal attenuated total reflectance (HATR) attachment of FTIR. DA can successfully classify VCO and that adulterated with CO and SFO using 10 principal components. Furthermore, PLS model correlates the actual and FTIR estimated values of oil adulterants (CO and SFO) with coefficient of determination (R2) of 0.999.

Matched MeSH terms: Fourier Analysis
Recent advances in the identification and authentication methods of edible bird's nest

Lee TH, Wani WA, Koay YS, Kavita S, Tan ETT, Shreaz S

Food Res Int, 2017 10;100(Pt 1):14-27.
PMID: 28873672 DOI: 10.1016/j.foodres.2017.07.036

Edible bird's nest (EBN) is an expensive animal bioproduct due to its reputation as a food and delicacy with diverse medicinal properties. One kilogram of EBN costs ~$6000 in China. EBN and its products are consumed in mostly Asian countries such as China, Hong Kong, Taiwan, Singapore, Malaysia, Indonesia, Vietnam and Thailand, making up almost 1/3 of world population. The rapid growth in EBN consumption has led to a big rise in the trade scale of its global market. Presently, various fake materials such as tremella fungus, pork skin, karaya gum, fish swimming bladder, jelly, agar, monosodium glutamate and egg white are used to adulterate EBNs for earning extra profits. Adulterated or fake EBN may be hazardous to the consumers. Thus, it is necessary to identify of the adulterants. Several sophisticated techniques based on genetics, immunochemistry, spectroscopy, chromatography and gel electrophoresis have been used for the detection of various types of adulterants in EBN. This article describes the recent advances in the authentication methods for EBN. Different genetic, immunochemical, spectroscopic and analytical methods such as genetics (DNA) based techniques, enzyme-linked immunosorbent assays, Fourier transform infrared and Raman spectroscopic techniques, and chromatographic and gel electrophoretic methods have been discussed. Besides, significance of the reported methods that might pertain them to applications in EBN industry has been described. Finally, efforts have been made to discuss the challenges and future perspectives of the authentication methods for EBN.

Matched MeSH terms: Fourier Analysis
A simple approach for rapid detection and quantification of adulterants in stingless bees (Heterotrigona itama) honey

Se KW, Ghoshal SK, Wahab RA, Ibrahim RKR, Lani MN

Food Res Int, 2018 03;105:453-460.
PMID: 29433236 DOI: 10.1016/j.foodres.2017.11.012

In this study, we propose an easy approach by combining the Fourier transform infrared and attenuated total reflectance (FTIR-ATR) spectroscopy together with chemometrics analysis for rapid detection and accurate quantification of five adulterants such as fructose, glucose, sucrose, corn syrup and cane sugar in stingless bees (Heterotrigona itama) honey harvested in Malaysia. Adulterants were classified using principal component analysis and soft independent modeling class analogy, where the first derivative of the spectra in the wavenumber range of 1180-750cm-1 was utilized. The protocol could satisfactorily discriminate the stingless bees honey samples that were adulterated with the concentrations of corn syrup above 8% (w/w) and cane sugar over 2% (w/w). Feasibility of integrating FTIR-ATR with chemometrics for precise quantification of the five adulterants was affirmed using partial least square regression (PLSR) analysis. The study found that optimal PLSR analysis achieved standard error of calibrations and standard error of predictions within an acceptable range of 0.686-1.087% and 0.581-1.489%, respectively, indicating good predictive capability. Hence, the method developed here for detecting and quantifying adulteration in H. itama honey samples is accurate and rapid, requiring only 7-8min to complete as compared to 3h for the standard method, AOAC method 998.12.

Matched MeSH terms: Fourier Analysis
CMF-iteMS: An automatic threshold selection for detection of copy-move forgery

Abd Warif NB, Idris MYI, Abdul Wahab AW, Salleh R, Ismail A

Forensic Sci Int, 2019 Feb;295:83-99.
PMID: 30576953 DOI: 10.1016/j.forsciint.2018.12.004

Taking into consideration that the prior CMF detection methods rely on several fixed threshold values in the filtering process, we propose an efficient CMF detection method with an automatic threshold selection, named as CMF-iteMS. The CMF-iteMS recommends a PatchMatch-based CMF detection method that adapts Fourier-Mellin Transform (FMT) as the feature extraction technique while a new automatic threshold selection based on iterative means of regions size (iteMS) procedure is introduced to have flexibility in changing the threshold value for various characteristics (quality, sizes, and attacks) in each input image. To ensure the reliability of the proposed CMF-iteMS, the method is compared with four state-of-the-art CMF detection methods based on Scale Invariant Feature Transform (SIFT), patch matching, multi-scale analysis and symmetry techniques using three available datasets that cover the variety of characteristics in CMF images. The results show that the F-score of the CMF-iteMS outperformed existing CMF detection methods by exceeding an average of 90% F-score values for image-level evaluation and 82% of F-score value for pixel-level evaluation for all datasets in original size. As special attention is given to the image resizing attack, the method is able to maintain the highest performance even if the images in the datasets are resized to 0.25 parameter.

Matched MeSH terms: Fourier Analysis
Fulltext Biosynthesized Silver Nanoparticles by Aqueous Stem Extract of Entada spiralis and Screening of Their Biomedical Activity

Wan Mat Khalir WKA, Shameli K, Jazayeri SD, Othman NA, Che Jusoh NW, Hassan NM

Front Chem, 2020;8:620.
PMID: 32974269 DOI: 10.3389/fchem.2020.00620

Silver nanoparticles (Ag-NPs) have been established as antibacterial nanoparticles and have been innovatively developed to overcome the occurrence of antibiotic resistance in the environment. In this study, an environmentally friendly and easy method of the biosynthesis of Ag-NPs plants, mediated by aqueous extract stem extract of Entada spiralis (E. spiralis), was successfully developed. The E. spiralis/Ag-NPs samples were characterized using spectroscopy and the microscopic technique of UV-visible (UV-vis), X-ray Diffraction (XRD), Field Emission Transmission Electron Microscope (FETEM), zeta potential, and Fourier Transform Infrared (FTIR) analyses. Surface Plasmon Resonance (SPR) absorption at 400-450 nm in the UV-vis spectra established the formation of E. spiralis/Ag-NPs. The crystalline structure of E. spiralis/Ag-NPs was displayed in the XRD analysis. The small size, around 18.49 ± 4.23 nm, and spherical shape of Ag-NPs with good distribution was observed in the FETEM image. The best physicochemical parameters on Ag-NPs biosynthesis using E. spiralis extract occurred at a moderate temperature (~52.0°C), 0.100 M of silver nitrate, 2.50 g of E. spiralis dosage and 600 min of stirring reaction time. The antibacterial activity was tested against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Proteus vulgaris using an antibacterial disk diffusion assay. Based on the results, it is evident that E. spiralis/Ag-NPs are susceptible to all the bacteria and has promising potential to be applied in both the industry and medical fields.

Matched MeSH terms: Fourier Analysis
Fulltext Application of Biochar Derived From Pyrolysis of Waste Fiberboard on Tetracycline Adsorption in Aqueous Solution

Xu D, Gao Y, Lin Z, Gao W, Zhang H, Karnowo K, et al.

Front Chem, 2019;7:943.
PMID: 32117859 DOI: 10.3389/fchem.2019.00943

In this study, biochars derived from waste fiberboard biomass were applied in tetracycline (TC) removal in aqueous solution. Biochar samples were prepared by slow pyrolysis at 300, 500, and 800°C, and were characterized by ultimate analysis, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), etc. The effects of ionic strength (0-1.0 mol/L of NaCl), initial TC concentration (2.5-60 ppm), biochar dosage (1.5-2.5 g/L), and initial pH (2-10) were systemically determined. The results present that biochar prepared at 800°C (BC800) generally possesses the highest aromatization degree and surface area with abundant pyridinic N (N-6) and accordingly shows a better removal efficiency (68.6%) than the other two biochar samples. Adsorption isotherm data were better fitted by the Freundlich model (R2 is 0.94) than the Langmuir model (R2 is 0.85). Thermodynamic study showed that the adsorption process is endothermic and mainly physical in nature with the values of ΔH0 being 48.0 kJ/mol, ΔS0 being 157.1 J/mol/K, and ΔG0 varying from 1.02 to -2.14 kJ/mol. The graphite-like structure in biochar enables the π-π interactions with a ring structure in the TC molecule, which, together with the N-6 acting as electron donor, is the main driving force of the adsorption process.

Matched MeSH terms: Fourier Analysis
Fulltext Predicting the degradation potential of Acid blue 113 by different oxidants using quantum chemical analysis

Asghar A, Bello MM, Raman AAA, Daud WMAW, Ramalingam A, Zain SBM

Heliyon, 2019 Sep;5(9):e02396.
PMID: 31517121 DOI: 10.1016/j.heliyon.2019.e02396

In this work, quantum chemical analysis was used to predict the degradation potential of a recalcitrant dye, Acid blue 113, by hydrogen peroxide, ozone, hydroxyl radical and sulfate radical. Geometry optimization and frequency calculations were performed at 'Hartree Fock', 'Becke, 3-parameter, Lee-Yang-Parr' and 'Modified Perdew-Wang exchange combined with PW91 correlation' levels of study using 6-31G* and 6-31G** basis sets. The Fourier Transform-Raman spectra of Acid blue 113 were recorded and a complete analysis on vibrational assignment and fundamental modes of model compound was performed. Natural bond orbital analysis revealed that Acid blue 113 has a highly stable structure due to strong intermolecular and intra-molecular interactions. Mulliken charge distribution and molecular electrostatic potential map of the dye also showed a strong influence of functional groups on the neighboring atoms. Subsequently, the reactivity of the dye towards the oxidants was compared based on the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy values. The results showed that Acid blue 113 with a HOMO value -5.227 eV exhibits a nucleophilic characteristic, with a high propensity to be degraded by ozone and hydroxyl radical due to their lower HOMO-LUMO energy gaps of 4.99 and 4.22 eV respectively. On the other hand, sulfate radical and hydrogen peroxide exhibit higher HOMO-LUMO energy gaps of 7.92 eV and 8.10 eV respectively, indicating their lower reactivity towards Acid blue 113. We conclude that oxidation processes based on hydroxyl radical and ozone would offer a more viable option for the degradation of Acid blue 113. This study shows that quantum chemical analysis can assist in selecting appropriate advanced oxidation processes for the treatment of textile effluent.

Matched MeSH terms: Fourier Analysis
Fulltext Physico-mechanical, thermal and morphological properties of furfuryl alcohol/2-ethylhexyl methacrylate/halloysite nanoclay wood polymer nanocomposites (WPNCs)

Rahman MR, Hamdan S, Lai JCH, Jawaid M, Yusof FABM

Heliyon, 2017 Jul;3(7):e00342.
PMID: 28725868 DOI: 10.1016/j.heliyon.2017.e00342

In this study, the physical, morphological, mechanical and thermal properties of furfuryl alcohol/2-ethylhexyl methacrylate/halloysite nanoclay wood polymer nanocomposites (FA-co-EHMA-HNC WPNCs) were investigated. FA-co-EHMA-HNC WPNCs were prepared via an impregnation method and the properties of the nanocomposites were characterized through the weight percent gain, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), three-point flexural test, dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) analysis and moisture absorption test. The weight percent gain in the 50:50 FA-co-EHMA-HNC WPNC was the highest compared with the raw wood (RW) and other WPNCs. The FT-IR results confirmed that polymerization took place in the nanocomposites, especially 50:50 FA-co-EHMA-HNC WPNC, which had a reduced amount of hydroxyl groups. The SEM results revealed that the 50:50 FA-co-EHMA-HNC WPNC had the smoothest and most uniform surface among all of the nanocomposites. The 50:50 FA-co-EHMA-HNC WPNC showed the highest flexural strength and modulus of elasticity. The results revealed that the storage modulus and loss modulus of the FA-co-EHMA-HNC WPNCs were higher and the tan δ of FA-co-EHMA-HNC WNPCs was lower compared with the RW. The FA-co-EHMA-HNC WPNCs exhibited the higher thermal stability in the TGA and DSC analysis. The 50:50 FA-co-EHMA-HNC WPNC exhibited remarkably lower moisture absorption compared with the RW. Overall, this study proved that the ratio 50:50 FA-co-EHMA ratio was the most suitable for introduction in the in the RW.

Matched MeSH terms: Fourier Analysis

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