نتایج جستجو برای: supercritical fluid extraction

تعداد نتایج: 390022  

2009
ZORAN ZEKOVIĆ

The chemical composition of mentha essential oil and mentha extracts obtained at different pressures/temperatures by supercritical fluid extraction (SFE) were studied by GC–MS. The menthol content was also determined spectrophotometrically. The predominant compounds in the essential oil and in the CO2 extract obtained at 100 bar were L-menthon and menthole but at higher pressures (from 150 to 4...

2003
MARTHA J. M. WELLS Somenath Mitra

This chapter focuses on three widely used techniques for extraction of semivolatile organics from liquids: liquid–liquid extraction (LLE), solid-phase extraction (SPE), and solid-phase microextraction (SPME). Other techniques may be useful in selected circumstances, but these three techniques have become the extraction methods of choice for research and commercial analytical laboratories. A fou...

2004
J. D. Hubbard J. M. Downing M. S. Ram O. K. Chung

Cereal Chem. 81(6):693–698 Environmental concerns, the disposal cost of hazardous waste, and the time required for extraction in current methods encouraged us to develop an alternate method for analysis of wheat flour lipids. Supercritical fluid extraction (SFE) with carbon dioxide has provided that medium and the method is fully automatic. Crude fats or nonstarch free lipids (FL) were extracte...

Journal: :Intelligent Automation & Soft Computing 2003
Simon X. Yang Hao Li John Shi

Modeling of the relationship between the pressure and yield of biomaterials is an essential issue in supercritical fluid extraction. In this paper, neural networks are proposed for modeling of supercritical fluid extraction. First a three-layer neural network with a fast learning algorithm is used, and its performance is compared to a conventional model of the Peng-Robinson equation of state. A...

Journal: :Trends in Analytical Chemistry 2021

The development of automatized hyphenated systems is attractive to avoid sampling error, save time and reduce costs. Among these systems, on-line SFE-SFC allows the extraction, separation, detection molecules in an efficient, quick eco-friendly way. After a historical introduction explanation on use supercritical fluids for extraction or analysis, principles fluid (SFE) chromatography (SFC) wil...

2015
Mojtaba Delfanian Reza Esmaeilzadeh Kenari Mohammad Ali Sahari

The aim of this study was to compare the effects of solvent and ultrasound-assisted extraction methods with supercritical fluid extraction on antioxidant activity of loquat (Eriobotrya japonica Lindl.) fruit skin extract in stability of soybean oil at 25°C. Oxidative stability alterations of soybean oils containing 400 (SEA) and 1000 ppm (SEB) of ethanol extract, 400 (SSA) and 1000 ppm (SSB) of...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه فردوسی مشهد - دانشکده مهندسی 1387

چکیده ندارد.

2010
E. V. Lau S. Gan H. K. Ng

This paper aims to provide a review of the analytical extraction techniques for polycyclic aromatic hydrocarbons (PAHs) in soils. The extraction technologies described here include Soxhlet extraction, ultrasonic and mechanical agitation, accelerated solvent extraction, supercritical and subcritical fluid extraction, microwave-assisted extraction, solid phase extraction and microextraction, ther...

Journal: :Planta medica 2017
Johanna Scheuba Valerie-Katharina Wronski Judith M Rollinger Ulrike Grienke

In this study the first supercritical fluid based protocol for the extraction, analysis, and isolation of six polar compounds, i.e., o-vanillin (1), styracin (2), vanillin (3), trans-cinnamic acid (4), vanillic acid (5), and shikimic acid (6), was developed. First, eight styrax resin products (R1-R8) obtained from various Liquidambar tree species, which are known to contain compounds 2-6, were ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید