Optically Active Poly (hydrazide-imide)-MWCNT Nanocomposites through Ultrasound Assisted Preparation

Analysis methods developed specifically to determine the presence of ink and other optically active components in paper machine white waters or other process effluents are not available. It is generally more interest¬ing to quantify the effect of circulation water contaminants on end products. This study compares optical techniques to quantify the dirt in process water by two methods for test media preparation and measurement: direct process water filtration on a membrane foil and low-grammage sheet formation. The results show that ink content values obtained from various analyses cannot be directly compared because of fundamental issues involving test media preparation and the varied methodologies used to formulate the results, which may be based on different sets of assumptions. The use of brightness, luminosity, and reflectance and the role of scattering measurements as a part of ink content analysis are discussed, along with fine materials retention and measurement media selection. The study concludes with practical tips for case-dependent measurement methodology selection.

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Innovative Extraction Techniques for the Optimum Extraction of Phenolic Compounds from Peanut Meal and Evaluation of Their Biological Activities

Advances in Nutrition & Food Science ◽

10.33140/anfs.04.02.2 ◽

2019 ◽

Vol 4 (2) ◽

Keyword(s):

Phenolic Compounds ◽

Carcinoma Cell ◽

Biological Activities ◽

Peanut Meal ◽

Ultrasound Assisted Extraction ◽

Carcinoma Cell Lines ◽

Assisted Extraction ◽

Phenolic Extract ◽

Ultrasound Assisted ◽

Water Ratio

There is a worldwide demand for phenolic compounds (PC) because they exhibit several biological activities. This work aimed at extracting phenolic compounds from peanut meal. The methods of extraction were mainly: conventional solvent extraction (traditional methods) and ultrasound assisted extraction (recent methods) and comparing their results. Peanut meal (PM) was prepared by defatting with n-hexane, and then extracted by the two previous methods. First, the conventional solvents used were 80% methanol, ethanol, acetone, isopropanol, and distilled water. Then studied Different parameters such as meal: water ratio, also the effect of temperature and the pH on the extraction process. Second, ultrasonic assisted extractions (USAE), the parameters investigated were temperature, time and speed of sonication. Finally, all the extracts were analyzed by HPLC for their phenolic contents. Results indicated that the highest extracted PC achieved by solvents was in distilled water where 1:100, Meal: Water ratio which extracted 40 mg PC / g PM at 30& 35°C. Highest extracted PC was achieved by alkaline medium at pH 12 more than acidic and neutral medium. While (USAE) at speed 8 ultrasonication and temperature 30ᵒC, extracted 49.2mg PC /g PM. Sothe ultrasound assisted extraction exhibited great influence on the extraction of phenolic compounds from peanut meal. The ultrasonic peanut extract was examined for its antioxidant, antimicrobial and anticarcinogenic activities. The antioxidant activity of PM phenolic extract prepared by ultrasonic technique, was measured by, β-carotene, and DPPH methods, and reducing antioxidant power. Results revealed values: 84.57, 57.72 and 5960 respectively. The PM extract showed different levels of antimicrobial activity against the pathogenic bacteria used. As for the anticarcinogenic effect PM phenolic extract most effective on inhibiting colon carcinoma and lung carcinoma cell lines with IC50 = 20.7 and 20.8 µ/ml., respectively. This was followed by intestinal carcinoma and liver carcinoma cell lines with IC50= 39.6 and 40.2µ/ml.

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Microscopic Structure of Er-Related Optically Active Centers in Si

MRS Proceedings ◽

10.1557/proc-770-i7.1 ◽

2003 ◽

Vol 770 ◽

Author(s):

H. Przybylinska ◽

N. Q. Vinh ◽

B.A. Andreev ◽

Z. F. Krasil'nik ◽

T. Gregorkiewicz

Keyword(s):

Ground State ◽

Photoluminescence Spectrum ◽

Zeeman Effect ◽

Optically Active ◽

Single Type ◽

Active Centers ◽

Mbe Growth ◽

Spectral Components ◽

Er Doped ◽

Successful Observation

AbstractA successful observation and analysis of the Zeeman effect on the near 1.54 μm photoluminescence spectrum in Er-doped crystalline MBE-grown silicon are reported. A clearly resolved splitting of 5 major spectral components was observed in magnetic fields up to 5.5 T. Based on the analysis of the data the symmetry of the dominant optically active center was conclusively established as orthorhombic I (C2v), with g‼≈18.4 and g⊥≈0 in the ground state. The fact that g⊥≈0 explains why EPR detection of Er-related optically active centers in silicon may be difficult. Preferential generation of a single type of an optically active Er-related center in MBE growth confirmed in this study is essential for photonic applications of Si:Er.

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