Enhancing exterior durability of jack pine by photo-stabilization of acrylic polyurethane coating using bark extract. Part 1: Effect of UV on color change and ATR–FT-IR analysis

Green synthesis is one of the rapid and best ways for silver nanoparticles (AgNP) synthesis. In the present study, synthesis and bioactivity of AgNPs has been demonstrated using water beech (Fagus sylvatica L.) bark extract. The physical and chemical factors such as time, metal ion solution, and pH, which play a vital role in the AgNPs synthesis, were assessed. The AgNPs were characterized by ultraviolet-visible (UV-Vis) spectrometry, Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). Antioxidant and antimicrobial activity of the obtained AgNPs was evaluated. AgNPs were characterized by color change pattern, and the broad peak obtained at 420–475 nm with UV-Vis confirmed the synthesis of AgNPs. FT-IR results confirmed that phenols and proteins of beech bark extract are mainly responsible for capping and stabilization of synthesized AgNPs. TEM micrographs showed spherical or rarely polygonal and triangular particles with an average size of 32 nm at pH = 9, and 62 nm at pH = 4. Furthermore, synthesized AgNPs were found to exhibit antioxidant activity and have antibacterial effect against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa. These results indicate that bark extract of F. sylvatica L. is suitable for synthesizing stable AgNPs, which act as an excellent antimicrobial agent.

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Green Synthesis of Silver Nanoparticles via Phormidium sp. nov. (Cyanophyceae): Amelioration, Characterization and Assessment of the Antibacterial Potential Against Methicillin Resistant Staphylococcus aureus

Science of Advanced Materials ◽

10.1166/sam.2021.3863 ◽

2021 ◽

Vol 13 (2) ◽

pp. 209-216

Author(s):

Nermin A. El-Semary ◽

Mona Mabrouk ◽

Ahmed H. Faraag ◽

Mona Kilany ◽

Shymaa H. Omran ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Silver Nanoparticles ◽

Color Change ◽

Silver Ions ◽

Time Saving ◽

Methicillin Resistant ◽

Ft Ir ◽

Ir Analysis ◽

Stability Results ◽

Ft Ir Spectroscopy

The use and manufacturing of silver nanoparticles (AgNPs) have recently received considerable attention in many fields. Methicillin resistant Staphylococcus aureus (MRSA) causes infectious diseases in humans. Therefore, the aim of this work was to bio-synthesize AgNPs using the cyanobacteria Phormidium sp. extract and to use this extract with AgNPs to kill MRSA. Extracellular bio-formation of AgNPs by Phormidium sp. was scrutinized at various pH points and temperatures. Then, characterization and assessment of the antimicrobial power of the produced particles were performed. Extract and extract + AgNPs were screened using Fourier Transform Infra-Red (FT-IR) spectroscopy and electron microscopy. The manufacturing and fastness of AgNPs were monitored visually (by color change) and spectroscopically. FT-IR analysis uncovered the biomolecules in the extract that caused the reduction of silver ions, protected them from aggregation and supplied them with high stability. Results indicated that AgNPs are spheres of 9 nm diameter. AgNPs combined with the extract proved to be a powerful antibacterial factor against MRSA. Consequently, biosynthesis of silver nano-spheres using Phormidium sp. with high antagonistic potency against MRSA is considered as an eco-friendly, time-saving strategy and with potential medicinal significance.

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The VSC Adsorption on Hydrotalcite through Topochemical Reactions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.529-530.650 ◽

2012 ◽

Vol 529-530 ◽

pp. 650-653 ◽

Cited By ~ 4

Author(s):

Yoshiyuki Yokogawa ◽

Yutaro Yagi ◽

Hroya Sano ◽

Atsutomo Nakamura ◽

Ippei Kishida

Keyword(s):

Aqueous Solution ◽

Dimethyl Sulfide ◽

Color Change ◽

Diffraction Method ◽

X Ray Diffraction ◽

Dental Fillings ◽

Topochemical Reactions ◽

Heat Treated ◽

Ft Ir ◽

Ir Analysis

Volatile sulfur compounds (VSCs) such as hydrogen sulfide (H2S), methyl mercaptan and dimethyl sulfide produced in mouth. Some oral (Gram-negative) bacteria produce VSCs, which induces permeability of mucous membrane, cause the oral malordor, dental caries, color change of the dental fillings. Thus, material which adsorbs VSCs should be useful to keep health in mouth. Previously, we reported the H2S adsorptive properties of zeolite and hydrotalcite materials having micro pores. The amount of H2S adsorbed on the zeolite or hydrotalcite at room temperature was found to be around 300-400 ppm, and and 3 % of H2S was desorbed when heated at 400 °C. The hydrotalcite, whose compositon is Mg1-xAlx(OH)2Ax/n·mH2O, where A is CO32-, and x is 0.25, was heat-treated at 500 °C, and put into aqueous solution containing H2S. In this study, the relation between heat-treatment tempearture and the sulfide adsorption on hydrotalcite in aqueous solution was investigated. The hydrotalcite materials were hydrothermally synthesized and identified by powder X-ray diffraction method. The change in concentrations of H2S in aqueous solution was measured using FPD gas chromatography (GC). The concentrations of H2S was decreased with time for the hydrotalcite heated at 500 °C or 600 °C, and fell to 20 % for 12 hours. But, the concentration was decreased by 40% for 12 hours for the hydrotalcite materials heated at higher temperatue. XRD and FT-IR analysis revealed that the sulfides were into or out of the hydrotalcite structure through topochemical reactions.

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Polarized microbeam FT-IR analysis of single fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163496 ◽

1996 ◽

Vol 54 ◽

pp. 206-207

Author(s):

Liling Cho ◽

David L. Wetzel

Keyword(s):

Molecular Orientation ◽

Transition Point ◽

Polymer Fibers ◽

Single Fiber ◽

Wire Grid ◽

Polyester Fibers ◽

Ft Ir ◽

Ir Analysis ◽

The Relationship ◽

Wire Grid Polarizer

Polarized infrared microscopy has been used for forensic purposes to differentiate among polymer fibers. Dichroism can be used to compare and discriminate between different polyester fibers, including those composed of polyethylene terephthalate that are frequently encountered during criminal casework. In the fiber manufacturering process, fibers are drawn to develop molecular orientation and crystallinity. Macromolecular chains are oriented with respect to the long axis of the fiber. It is desirable to determine the relationship between the molecular orientation and stretching properties. This is particularly useful on a single fiber basis. Polarized spectroscopic differences observed from a single fiber are proposed to reveal the extent of molecular orientation within that single fiber. In the work presented, we compared the dichroic ratio between unstretched and stretched polyester fibers, and the transition point between the two forms of the same fiber. These techniques were applied to different polyester fibers. A fiber stretching device was fabricated for use on the instrument (IRμs, Spectra-Tech) stage. Tension was applied with a micrometer screw until a “neck” was produced in the stretched fiber. Spectra were obtained from an area of 24×48 μm. A wire-grid polarizer was used between the source and the sample.

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Synthesis and Evaluation of Levulinic Ester as Biodiesel Additives

Revista de Chimie ◽

10.37358/rc.20.8.8275 ◽

2020 ◽

Vol 71 (8) ◽

pp. 21-26

Author(s):

Elena-Emilia Oprescu ◽

Cristina-Emanuela Enascuta ◽

Elena Radu ◽

Vasile Lavric

Keyword(s):

Maximum Yield ◽

Strength Distribution ◽

Point Of View ◽

Reaction Parameters ◽

X Ray ◽

Ethyl Levulinate ◽

Ft Ir ◽

Ir Analysis ◽

Biodiesel Blend ◽

Acid Strength Distribution

In this study, the SO42-/TiO2-La2O3-Fe2O3 catalyst was prepared and tested in the conversion of fructose to ethyl levulinate . The catalyst was characterized from the point of view of the textural analysis, FT-IR analysis, acid strength distribution, X-ray powder diffraction and pyridine adsorption IR spectra. The influence of the reaction parameters on the ethyl levulinate yield was study. The maximum yield of 37.95% in levulinate esters was obtained at 180 �C, 2 g catalyst and 4 h reaction time. The effect of ethyl levulinate addition to diesel-biodiesel blend in different rates, i.e, 0.5, 1, 2.5, 5 (w.t %) on density, kinematic viscosity and flash point was evaluated and compared with the European specification.

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Formulation, Optimization,and Ex-Vivo Evaluation of Novel Lipid Carriers for Enhanced Transdermal Delivery of Hydroquinone

Micro and Nanosystems ◽

10.2174/1876402912999200831105145 ◽

2020 ◽

Vol 12 ◽

Author(s):

Shivani Verma ◽

Sukhjinder Kaur ◽

Lalit Kumar

Keyword(s):

Ex Vivo ◽

Skin Permeation ◽

Topical Delivery ◽

Gelling Agent ◽

Minimum Size ◽

Prolonged Release ◽

Freeze Dried ◽

Ft Ir ◽

Ir Analysis ◽

Skin Retention

Background: HQ is used for hyper-pigmentation treatment using conventional creams and gels. These formulations show various disadvantages like poor skin permeation, allergic reactions, and repeated use decreasing patient compliance. Objectives: The present work involved formulation, statistical optimization, and characterization of nanostructured lipid carriers (NLCs) for efficient topical delivery of hydroquinone (HQ) for hyperpigmentation treatment. Methods: The NLCs were optimized exploring Box–Behnken design (BBD) using three independent variables and two dependent variables. Formulation having the minimum size and maximum drug entrapment was considered as optimized formulation. Optimized formulation was evaluated for drug release followed by its freeze-drying. The freeze-dried formulation was subjected to differential scanning calorimetry (DSC) analysis, X-raydiffraction (XRD) analysis, and Fourier transform-infrared spectroscopy (FT-IR) analysis. Furthermore, NLCs based gel was prepared by using Carbopol 934 as a gelling agent. NLCs based gel was evaluated for skin permeation, skin retention, and skin distribution (through confocal microscopic analysis) using pig ear skin. Results: Optimized NLCs showed smaller particle size [(271.9 ± 9) nm], high drug entrapment [(66.4 ± 1.2) %], tolerable polydispersity index (PDI) (0.221 ± 0.012), and zeta potential [(-25.9± 1.2) mV]. The FT-IR analysis revealed excellent compatibility between HQ and other excipients. The Carbopol 934 gel containing NLCs showed high transdermal flux [(163 ± 16.2) μg/cm2/h], permeability coefficient (0.0326 ± 0.0016), and skin permeation enhancement ratio (3.7 ± 0.4) compared to marketed cream of HQ. The results of confocal microscopic (CLSM) analysis revealed the accumulation of optimized NLCs in the lower epidermal layers of skin. Conclusion: NLCs based gel was considered effective in the topical delivery of HQ to treat hyper-pigmentation due high skin permeation, skin retention, and prolonged release of HQ.

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Impact of Chemical Modification on the Physical and Mechanical Properties of Tropical Wood Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.576.314 ◽

2012 ◽

Vol 576 ◽

pp. 314-317

Author(s):

Sinin Hamdan ◽

M. Saiful Islam

Keyword(s):

Mechanical Properties ◽

Diazonium Salt ◽

Treated Wood ◽

Coupling Reaction ◽

Physical And Mechanical Properties ◽

Modulus Of Rupture ◽

Ft Ir ◽

Ir Analysis ◽

D Values ◽

Benzene Diazonium

Five types of selected tropical light hardwoods were chemically modified with benzene diazonium salt to improve their physical and mechanical properties. Benzene diazonium salt underwent a coupling reaction with wood which was confirmed through FT-IR analysis. The compressive modulus of the treated wood increased, whereas modulus of rupture was shown to decrease on treatment. The modified wood samples had higher hardness (Shore D) values compared to that of the control ones.

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