scholarly journals Effect of Various Pretreatment for Extracting Intracellular Lipid from Nannochloropsis oculata under Nitrogen Replete and Depleted Conditions

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Duraiarasan Surendhiran ◽  
Mani Vijay
Keyword(s):  
Fluorescent Microscopy ◽  
Nile Red ◽  
Nannochloropsis Oculata ◽  
Biodiesel Production ◽  
Enzyme Treatment ◽  
Effective Technique ◽  
Intracellular Lipid ◽  
Ft Ir ◽  
Ft Ir Spectroscopy ◽  
Algal Cultures

Microalga is one of the most compelling microbial biomasses for biodiesel production. Various pretreatment processes, namely, enzyme treatment, lysis by acid, ultrasonicator, microwaves, autoclave, and 40% NaCl, for nitrogen replete and depleted algal cultures of Nannochloropsis oculata had been carried out to check the most feasible and effective technique to disrupt cells for procuring lipids, for which concentrations were determined. Fatty acid composition, essential functional groups, and cell disruption were analyzed by GC-MS, FT-IR Spectroscopy, and Nile Red fluorescent microscopy, respectively. The present investigation showed that lipid yield was higher in nitrogen depleted cells than that in normally nourished cells. GC-MS revealed the presence of major fatty acids—palmitic, oleic, stearic, arachidic, lauric, and linoleic acids. Highest efficiency was found when cells were pretreated using acid for 3 h. The lipid content was calculated as 33.18% and 54.26% for nitrogen rich cells and nitrogen starved cells, respectively. This work thus aided in identifying the most eligible pretreatment process to avail lipids from cells, to convert them to eco-friendly and nonpolluting biodiesel.

Molecular Sieve Thin Films via Laser Ablation

1994 ◽  
Vol 351 ◽  
Author(s):  
Kenneth J. Balkus ◽  
Scott J. Riley ◽  
Bruce E. Gnade
Keyword(s):  
Thin Films ◽  
Laser Ablation ◽  
Molecular Sieves ◽  
Molecular Sieve ◽  
Film Formation ◽  
Aluminum Phosphate ◽  
Effective Technique ◽  
Solid Films ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

ABSTRACTLaser ablation has become widely recognized as an effective technique for the preparation of thin solid films. We have employed an excimer laser (KrF, 248 nm) to deposit well dispersed thin films of aluminum phosphate molecular sieves on a titanium nitride substrate. Results for the ablation of AIPO4-5, AIPO4-H3 and AIPO4-H1 molecular sieve targets are presented. The laser power and repetition rate as well as substrate distance and temperature affect the thin film formation. A subsequent hydrothermal post treatment of the ablated films was found to enhance the surface crystallinity. The molecular sieve thin films were characterized by XRD, SEM, XRF, and FT-IR spectroscopy.

scholarly journals Production and Characterization of Biodiesel from Aphanamixis polystachya Seed Oil

2020 ◽  
Vol 68 (2) ◽  
pp. 129-136
Author(s):  
Sazia Ifteqar ◽  
Rajia Sultana ◽  
Sujit Banik ◽  
AFM Mustafizur Rahman
Keyword(s):  
Seed Oil ◽  
Biodiesel Production ◽  
Optimum Conditions ◽  
Alternative Diesel Fuel ◽  
Biodiesel Standards ◽  
Ft Ir ◽  
Acid Catalyzed ◽  
Edible Seed ◽  
Ft Ir Spectroscopy

The present study focuses on the utilization of non-edible Aphanamixis polystachya seed oil as a potential feedstock for the production of biodiesel. The extracted oil from non-edible seed could not be directly exploited for biodiesel production owing to its high free fatty acid (FFA) content of 5.785%, so acid catalyzed esterification was applied to reduce FFA of oil to zero followed by base-catalyzed transesterification to convert esterified product to its mono-esters. Thermogravimetric analysis (TGA) revealed that the mass percentage corresponding to biodiesel under optimum conditions was 74.38%. The conversion of the triglycerides in the oil into biodiesel through transesterification was confirmed using FT-IR spectroscopy. The elemental analysis of the produced biodiesel was studied. The produced biodiesel had properties which were comparable with biodiesel standards and could be utilized as an alternative diesel fuel without any hardware modifications. Dhaka Univ. J. Sci. 68(2): 129-136, 2020 (July)

Microplastics Differ Between Indoor and Outdoor Air Masses: Insights from Multiple Microscopy Methodologies

2020 ◽  
Vol 74 (9) ◽  
pp. 1079-1098 ◽  
Author(s):  
Emily Gaston ◽  
Mary Woo ◽  
Clare Steele ◽  
Suja Sukumaran ◽  
Sean Anderson
Keyword(s):  
Indoor Air ◽  
Fluorescent Microscopy ◽  
Inhalation Exposure ◽  
Nile Red ◽  
Outdoor Air ◽  
Air Masses ◽  
Ft Ir ◽  
Abundance And Distribution ◽  
Microscopy Techniques ◽  
Indoor And Outdoor

The abundance and distribution of microplastic (<5 mm) has become a growing concern, particularly over the past decade. Research to date has focused on water, soil, and organism matrices but generally disregarded air. We explored airborne microplastic inside and outside of buildings in coastal California by filtering known volumes of air through glass fiber filters, which were then subsequently characterized with a variety of microscopy techniques: gross traditional microscopy, fluorescent microscopy following staining with Nile red, micro-Raman spectroscopy, and micro-Fourier transform infrared (µFT-IR) spectroscopy. Microplastics permeated the air, with indoor (3.3 ± 2.9 fibers and 12.6 ± 8.0 fragments m–3; mean ± 1 SD) harboring twice as much as outdoor air (0.6 ± 0.6 fibers and 5.6 ± 3.2 fragments m–3). Microplastic fiber length did not differ significantly between indoor and outdoor air, but indoor microplastic fragments (58.6 ± 55 µm) were half the size of outdoor fragments (104.8 ± 64.9 µm). Micro-Raman and FT-IR painted slightly different pictures of airborne plastic compounds, with micro-Raman suggesting polyvinyl chloride dominates indoor air, followed by polyethylene (PE) and µFT-IR showing polystyrene dominates followed by PE and polyethylene terephthalate. The ubiquity of airborne microplastic points to significant new potential sources of plastic inputs to terrestrial and marine ecosystems and raises significant concerns about inhalation exposure to humans both indoors and outdoors.

scholarly journals A novel method for extraction, quantification, and identification of microplastics in CreamType of cosmetic products

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Soohyun Lee ◽  
Tai Gyu Lee
Keyword(s):  
Nile Red ◽  
Cosmetic Products ◽  
Digestion Method ◽  
Accurate Analysis ◽  
Sem Images ◽  
Cosmetic Ingredients ◽  
Before And After ◽  
Ft Ir ◽  
Novel Method ◽  
Ft Ir Spectroscopy

AbstractThe objective of this study was to develop an accessible and accurate analysis method for microplastics that have been unintentionally added to cream cosmetic products. An experiment was performed on three cleansing creams in rich and viscous formulations. A spiked sample was prepared by adding polyethylene (PE) microspheres to the cleansing creams. After removing cosmetic ingredients from the creams using chemical digestion, damage to the PE microspheres was identified using Fourier transform infrared (FT-IR) spectroscopy. Field emission scanning electron microscopy (FE-SEM) images were obtained before and after digestion and used to characterize the morphology of the PE microspheres. The highest digestion efficiency was obtained using a chemical digestion method consisting of heating and stirring a sample in a 10 wt% KOH solution at 55 °C and 300 rpm for 5 days and did not damage the PE microspheres. The Nile red (9-diethylamino-5H-benzo[α]phenoxazine-5-one) staining method was effective in identifying small microplastics (< 106 μm). The optimal staining conditions are 5 μg/ml Nile red in n-hexane for green wavelengths.

scholarly journals Dissecting lipid accumulation of microalgae Nannochloropsis oculata using fluorescent image analysis

2019 ◽  
Vol 2 (5) ◽  
pp. 5-11
Author(s):  
Tu Cam Trinh ◽  
Huong Thanh Tran ◽  
Viet Trang Bui
Keyword(s):  
Cell Suspension ◽  
Cell Density ◽  
Lipid Accumulation ◽  
Lipid Droplets ◽  
Nile Red ◽  
Nannochloropsis Oculata ◽  
Cell Diameter ◽  
Intracellular Lipid ◽  
Processing Program ◽  
Intracellular Lipid Accumulation

Cell suspension of Nannochloropsis oculata was cultured in a modified f/2 medium to study the changes of lipid content during phases of growth. The growth of cell suspension was determined by measuring the cell density and diameter under light microscope. To observe and evaluate the accumulation of lipid droplets in microalgae cells, lipid droplets were stained with Nile Red fluorescent dye then examined under fluorescence microscope and the obtained images were analyzed using Fiji ImageJ, an image processing program. The cell density increased quickly at the first 6 days of culture while cell diameter reached the highest value at the 8th day and 20th day of culture. The presence of lipid droplets in the cells could be observed from the 20th day of culture. The size of lipid droplets was gradually increased after 60 days. Treatment of depleted nitrogen for 4 days resulted an increase in the accumulation of lipid. The intracellular lipid accumulation during phases of growth of the cell suspension under nitrogen-depleted conditions was also discussed.

scholarly journals The Preparation, Thermal Properties, and Fire Property of a Phosphorus-Containing Flame-Retardant Styrene Copolymer

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 127 ◽  
Author(s):  
Yu Sun ◽  
Yazhen Wang ◽  
Li Liu ◽  
Tianyuan Xiao
Keyword(s):  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Limiting Oxygen Index ◽  
Chemical Structures ◽  
1H Nuclear Magnetic Resonance ◽  
Phosphorus Containing ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

A 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) acrylate, (6-oxidodibenzo [c,e][1,2] oxaphosphinin-6-yl) methyl acrylate (DOPOAA), has been prepared. Copolymers of styrene (St) and DOPOAA were prepared by emulsion polymerization. The chemical structures of copolymers containing levels of DOPOAA were verified using Fourier transform infrared (FT-IR) spectroscopy and 1H nuclear magnetic resonance (1H-NMR) spectroscopy. The thermal properties and flame-retardant behaviors of DOPO-containing monomers and copolymers were observed using thermogravimetric analysis and micro calorimetry tests. From thermogravimetric analysis (TGA), it was found out that the T5% for decomposition of the copolymer was lower than that of polystyrene (PS), but the residue at 700 °C was higher than that of PS. The results from micro calorimetry (MCC) tests indicated that the rate for the heat release of the copolymer combustion was lower than that for PS. The limiting oxygen index (LOI) for combustion of the copolymer rose with increasing levels of DOPOAA. These data indicate that copolymerization of the phosphorus-containing flame-retardant monomer, DOPOAA, into a PS segment can effectively improve the thermal stability and flame retardancy of the copolymer.

Multiscale exploration of hydrocarbons adsorption and hopping through the ZSM-5 channels - from Monte Carlo modelling to experiment

2021 ◽  
Author(s):  
Maciej Strzempek ◽  
Karolina A. Tarach ◽  
Kinga Góra-Marek ◽  
Fernando Rey ◽  
Miguel Palomino ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Ir Spectroscopy ◽  
Aliphatic Hydrocarbons ◽  
Adsorption Studies ◽  
Ft Ir ◽  
Gravimetric Adsorption ◽  
Hydrocarbons Adsorption ◽  
Ft Ir Spectroscopy

Abstract In this article the results of the statistical MC modelling corroborated by the FT-IR spectroscopy and gravimetric adsorption studies of the low aliphatic hydrocarbons in ZSM-5 (Si/Al =28 or...

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