Decontamination Options of the Packaging Wastes from Toxic Substances

2008 ◽  
Vol 59 (4) ◽  
Author(s):  
Sanda Velea ◽  
Sever Serban ◽  
Daniela Stilpeanu ◽  
Lucia Ilie
Keyword(s):  
Scientific Information ◽  
Research Priorities ◽  
Analytical Techniques ◽  
Polymeric Materials ◽  
Extraction Process ◽  
Original Method ◽  
Ultrasonic Extraction ◽  
Toxic Substances ◽  
Pyrethroid Insecticides ◽  
Packaging Waste

The implementation of Directive 94/62/EC on packaging and packaging waste has meant a great change on the Romanian legislation and on the research priorities in this area in our country. For this reason, the decontamination options of reusable containers became the aim of this paper, which was prepared in order to evaluate the possibilities of safe recycling of clean containers to the manufacturer or supplier. Our studies have developed ultrasonic extraction, original method for the residual pesticides content such as pyrethroid insecticides e.g. as Deltamethrin 2.5 EC from plastic containers used for pesticide packaging. Thus, we considered the need to examine how polar solvents, e.g propylene glycol, behave in the ultrasonic extraction process of residual pesticides from packaging waste. The efficiency of ultrasonic extraction was determined by advanced analytical techniques such as thermal analysis: thermo gravimetrical (TGA) and calorimetrical (DSC) methods in order to provide scientific information about the residue pesticide level in polymeric materials from pesticide packaging waste. The ultrasonic extraction yield for the pyrethroid insecticide Deltamethrin from used polyethylene from Decis 2.5% packaging is over 98%. The optimum extraction time, in the preliminary experiments, was 60 minutes, after which, using the differential calorimetry method, the pesticide Deltamethrin is no longer found in the sonicated polyethylene samples.

Study of Transport Phenomena in Guayule Deresination

1981 ◽  
Vol 54 (4) ◽  
pp. 871-881 ◽  
Author(s):  
S. Budiman ◽  
D. McIntyre
Keyword(s):  
Natural Rubber ◽  
Diffusion Coefficients ◽  
Current Knowledge ◽  
Analytical Techniques ◽  
Polymeric Materials ◽  
Extraction Process ◽  
Transport Processes ◽  
Research Station ◽  
Transport Parameters ◽  
Alternative Source

Abstract Renewed interest in guayule as an alternative source of natural rubber has brought the processing aspect back into focus as an important determinant in the effort of guayule commercialization. To meet the current technological requirement, the quality of the guayule rubber needs to be standardized like the presently known Technically Specified Natural Rubber. In order to produce good standard quality guayule rubber, the resin constituent must be thoroughly and consistently eliminated. This condition stipulates an effective and efficient extraction process which in consequence demands a thorough understanding of the resin compounds and their behavior during extraction with acetone. The emphasis of this study is to examine the physical state of resin inclusion in the rubber and the mechanism of its removal during solvent extraction. The ultimate objective is to determine the necessary transport parameters in the deresination process of guayule latex coagulum, better known as ‘worms’ in popular terminology. Worm deresination was used in guayule processing in the U. S. during World War II, and it is currently also performed in the CIQA Pilot Plant in Saltillo, Mexico. Previous work on the subject had been carried out by Banigan and Clark of the U. S. Natural Rubber Research Station at Salinas, California in the early 1950's. Banigan had determined that the worm deresination occurred by diffusion and made experiments to determine diffusion coefficients using thin sheets of dried worms with acetone, ethanol and methylethyl ketone as solvents. He also noted the possibility of two different diffusion coefficients due to the mixed nature of guayule resin. Recent investigations at CIQA have confirmed that the resin consists of two major groups, namely the nonvolatiles and the volatiles. The nonvolatile components are mainly fatty acid triglycerides, while the volatiles are terpenoids such as α-pinene, dipentene, etc. The present study attempts to provide more detailed transport data using modem analytical techniques and the current knowledge of transport processes in polymeric materials. Since the available diffusion data are only for dried worms, whereas in reality the worms are deresinated in the wet state, the present work has used wet worms as the study material.

Recent Developments in CE-MS Based Metabolomics

2020 ◽  
Vol 16 ◽  
Author(s):  
Mustafa Çelebier ◽  
Merve Nenni
Keyword(s):  
Sample Preparation ◽  
Scientific Information ◽  
Analytical Techniques ◽  
Living Organism ◽  
Analytical Technique ◽  
Ionic Compounds ◽  
Recent Sample ◽  
Recent Developments ◽  
Endogenous Metabolites ◽  
Preparation Techniques

Background: Metabolomics has gained importance in clinical applications over the last decade. Metabolomics studies are significant because the systemic metabolome is directly affected by disease conditions. Metabolome-based biomarkers are actively being developed for early diagnosis and to indicate the stage of specific diseases. Additionally, understanding the effect of an intervention on a living organism at the molecular level is a crucial strategy for understanding novel or unexpected biological processes. Results: The simultaneous improvements in advanced analytical techniques, sample preparation techniques, computer technology, and databank contents has enabled more valuable scientific information to be gained from metabolomics than ever before. With over 15,000 known endogenous metabolites, there is no single analytical technique capable of analyzing the whole metabolome. However, capillary electrophoresis-mass spectrometry (CE-MS) is a unique technique used to analyze an important portion of metabolites not accessible by liquid chromatography or gas chromatography techniques. The analytical capability of CE, combined with recent sample preparation techniques focused on extracting polar-ionic compounds, make CE-MS a perfect technique for metabolomic studies. Conclusion: Here, previous reviews of CE-MS based metabolomics are evaluated to highlight recent improvements in this technique. Specifically, we review papers from the last two years (2018 and 2019) on CE-MS based metabolomics. The current situation and the challenges facing metabolomic studies are discussed to reveal the high potential of CE-MS for further studies, especially in biomarker development studies.

Extraction of Mogroside and Limonin with Different Extraction Methods and its Modeling

2012 ◽  
Vol 8 (2) ◽  
Author(s):  
Jing Liu ◽  
Can Liu ◽  
Yonghai Rong ◽  
Long Rong
Keyword(s):  
Thin Film ◽  
Natural Products ◽  
Mass Production ◽  
Extraction Process ◽  
Extraction Methods ◽  
Ultrasonic Extraction ◽  
Citrus Reticulata ◽  
Comparison Of Methods ◽  
Economical Method ◽  
Siraitia Grosvenorii

The extraction yields of mogroside from Siraitia grosvenorii fruits and limonin from orange (Citrus reticulata Blanco) seeds were compared with different extraction methods, respectively. Maceration extraction, stirring extraction, ultrasonic extraction and flash extraction were used for the extraction. The extraction process was modeled using the concept of thin film which provides the resistance to transfer. The results showed that the maximum yields of mogroside (4.11%) and limonin (0.65%) were obtained by ultrasonic extraction and flash extraction respectively. Owing to its shorter extraction time, flash extraction would be an economical method for the mass production of triterpenes from natural products. The model was found to be fit for the comparison of methods for the extraction and provided good correlation of the data. The model could be mainly used in the practical extraction process.

Renale opruiming van melatonien

1996 ◽  
Vol 15 (1) ◽  
pp. 3-6
Author(s):  
Editorial Office
Keyword(s):  
Renal Clearance ◽  
Oral Intake ◽  
Analytical Techniques ◽  
Extraction Process ◽  
The Hours

Only two publications exist in which actual values for the renal clearance of intact melatonin in man is described. The melatonin clearance values were, however, obtained either after the oral intake of melatonin, or by applying different techniques for the determination of melatonin in urine and plasma. In this study, renal clearance of melatonin was determined during the hours where melatonin concentrations are relatively constant. Melatonin levels in plasma and urine respectively were each deter­mined by three analytical techniques, i.e. the Fraser, NID and WHB methods. The results show renal clearance of melatonin to be under 2 ml/min and that higher values are obtained with analytical techniques which bypass the extraction process.

Developing Biological Endpoints for Defining Virtual Elimination: a Case Study for PCDDs and PCDFs

1999 ◽  
Vol 34 (3) ◽  
pp. 391-422
Author(s):  
M.R. Servos ◽  
J.L. Parrott ◽  
J.P. Sherry ◽  
S.B. Brown
Keyword(s):  
Traditional Approach ◽  
Biological Effects ◽  
Detection Limits ◽  
Analytical Techniques ◽  
Management Policy ◽  
Toxic Substances ◽  
Biological Responses ◽  
Considerable Debate ◽  
Mixed Function Oxygenase

Abstract Defining virtual elimination has created considerable debate. A traditional approach has been to use chemically defined detection limits or levels of quantification that are determined using the best currently available methodologies. Ever increasing improvements in analytical techniques could lead to corresponding pressure to reduce the targets for virtual elimination. The current Toxic Substances Management Policy in Canada recognizes this and clearly states that it is not the intent of virtual elimination to have a moving target or to chase down the last molecule of the chemical of concern. Although it may be possible to reduce a chemical to less than some extremely sensitive detection limit, the chemical may or may not exert biological effects at that level. The chemically defined detection limits may be much lower than background levels in the environment, making it an unrealistic target. Conversely biological responses may result from trace levels of a compound that are not detectable in effluents or selected compartments of the environment (i.e., water) using current chemical techniques. Alternatively, an effect-based approach can establish biologically meaningful endpoints to defining virtual elimination. Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are used in this study as an example to evaluate the advantages and limitations of several possible approaches of using biological endpoints to determine the presence of these compounds in the environment and ultimately define virtual elimination. A review of the biological responses to PCDD/PCDFs is included to demonstrate the importance of selecting appropriate biological endpoints. Mixed function oxygenase (MFO) induction, although not recommended at this point, is used as an example of a possible sensitive endpoint that could potentially be used to detect exposure of biota to these chemicals. Three different approaches are explored: (1) measuring MFO induction in a sentinel species in the environment; (2) testing environmental extracts for MFO induction in cell lines; and (3) using biological endpoints (MFO induction) to define chemical targets for virtual elimination. While the use of biological end-points is the most desirable approach to defining virtual elimination, there are significant knowledge gaps which limit our selection and application of this approach.

Kinetics on the Ultrasonic-Assisted Extraction of Polysaccharides from Limonium bicolor kunze (Bge.)

2014 ◽  
Vol 1003 ◽  
pp. 3-6
Author(s):  
Xiao Song ◽  
Peng Zhao ◽  
Qing Hua Meng ◽  
Zhi Shu Tang ◽  
Chang Li Wang
Keyword(s):  
Kinetic Equation ◽  
Extraction Process ◽  
Ultrasonic Extraction ◽  
Second Law ◽  
Technical Design ◽  
Kinetics Parameters ◽  
Limonium Bicolor ◽  
Assisted Extraction ◽  
Ultrasonic Assisted ◽  
Ultrasonic Assisted Extraction

To explore the kinetics parameters in the ultrasonic-assisted extraction from Limonium bicolor Kunze (Bge.) , the kinetic equation for polysaccharide ultrasonic extraction process was established with ball model. According to Fick’s second law of diffusion, extraction process was analysed. The results can provide the valuable theory basis for the technical design and further research of polysaccharide extraction process.

Extraction and Chromatography-Mass Spectrometric Analysis of the Active Principles from Selected Chinese Herbs and Other Medicinal Plants

2003 ◽  
Vol 31 (06) ◽  
pp. 927-944 ◽  
Author(s):  
Xiaosuo Wang ◽  
Vimal Kapoor ◽  
George A. Smythe
Keyword(s):  
Mass Spectrometry ◽  
Analytical Techniques ◽  
Mass Spectrometric ◽  
Chinese Herbs ◽  
Spectrometric Analysis ◽  
Toxic Substances ◽  
Herbal Extracts ◽  
Active Components ◽  
Herbal Products ◽  
Isolation And Characterization

Medicinal herbs have a long history of use in the practice of traditional Chinese medicine and a substantial body of evidence has, over recent decades, demonstrated a range of important pharmacological properties. Western biomedical researchers are examining not only the efficacy of the traditional herbal products but, through the use of a range of bioassays and analytical techniques, are developing improved methods to isolate and characterize active components. This review briefly describes the different extraction methodologies used in the preparation of herbal extracts and reviews the utility of chromatography-mass spectrometry for the analysis of their active components. In particular, applications of gas or liquid chromatography with mass spectrometry for the isolation and characterization of active components of ginseng are critically assessed. The analysis of toxic substances from herb extracts with mass spectrometric techniques is also discussed along with the potential for mass spectrometric methods to investigate the proteomics of herbal extracts.

Ultrasonic Extraction Chuanxiong Polysaccharide of Influencing Factors

2012 ◽  
Vol 550-553 ◽  
pp. 1071-1075
Author(s):  
Yong Guang Bi ◽  
Chun Chun Liu
Keyword(s):  
Influencing Factors ◽  
Extraction Process ◽  
Extraction Rate ◽  
Ultrasonic Extraction ◽  
Ultrasonic Power ◽  
Extraction Temperature ◽  
Liquid Ratio ◽  
Ultrasonic Time ◽  
Solid Liquid

In order to study the the Chuanxiong polysaccharide ultrasonic extraction process, examine the ultrasonic time, ultrasonic power, solid-liquid ratio and extraction temperature on the Chuanxiong polysaccharide extract rate. The results show that the role of time at 30min Polysaccharide better, the extraction rate is 26.63%. when the ultrasonic power is 320W, Polysaccharide extraction rate is 26.15%.When the solid-liquid ratio is 1:20, polysaccharide extraction rate is 27.73%. When the extraction temperature is 60°C, the polysaccharide extraction rate is 27.73%.

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