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Predicting partitioning of volatile organic compounds from air into plant cuticular matrix by quantum chemical descriptors
Chunlei Zhang,Liu Feng,Jie Wei
Chinese Science Bulletin , 2002, DOI: 10.1360/02tb9281
Abstract: Based on theoretical linear solvation energy relationship and quantum chemical descriptors computed by AM1 Hamiltonian, a new model is developed to predict the partitioning of some volatile organic compounds between the plant cuticular matrix and air.
QSPR Models for Predicting Log Pliver Values for Volatile Organic Compounds Combining Statistical Methods and Domain Knowledge  [PDF]
Damián Palomba,María J. Martínez,Ignacio Ponzoni,Mónica F. Díaz,Gustavo E. Vazquez,Axel J. Soto
Molecules , 2012, DOI: 10.3390/molecules171214937
Abstract: Volatile organic compounds (VOCs) are contained in a variety of chemicals that can be found in household products and may have undesirable effects on health. Thereby, it is important to model blood-to-liver partition coefficients (log Pliver) for VOCs in a fast and inexpensive way. In this paper, we present two new quantitative structure-property relationship (QSPR) models for the prediction of log Pliver, where we also propose a hybrid approach for the selection of the descriptors. This hybrid methodology combines a machine learning method with a manual selection based on expert knowledge. This allows obtaining a set of descriptors that is interpretable in physicochemical terms. Our regression models were trained using decision trees and neural networks and validated using an external test set. Results show high prediction accuracy compared to previous log Pliver models, and the descriptor selection approach provides a means to get a small set of descriptors that is in agreement with theoretical understanding of the target property.
General analytical mass transfer model for VOC emissions from multi-layer dry building materials with internal chemical reactions
XinKe Wang,YinPing Zhang
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-010-4254-5
Abstract: A general mass transfer based model was developed for analyzing volatile organic compound (VOC) emissions from dry multi-layer building materials with two emission surfaces. This model adds to an earlier multi-layer model by considering chemical reactions within the materials. Consequently, it can be used to analyze the effect of these chemical reactions on removing VOCs, and for characterizing secondary VOC emissions from the building material. The model was validated with literature data and our experimental results. Some typical secondary emissions were analyzed using this model, and obviously differed from the primary emissions. The model is a useful tool for predicting, analyzing and “designing” the VOC emission characteristics, including secondary emissions, of building materials.
General analytical mass transfer model for VOC emissions from multi-layer dry building materials with internal chemical reactions

WANG XinKe,ZHANG YinPing,

科学通报(英文版) , 2011,
Abstract: A general mass transfer based model was developed for analyzing volatile organic compound (VOC) emissions from dry multi-layer building materials with two emission surfaces. This model adds to an earlier multi-layer model by considering chemical reactions within the materials. Consequently, it can be used to analyze the effect of these chemical reactions on removing VOCs, and for characterizing secondary VOC emissions from the building material. The model was validated with literature data and our experimental results. Some typical secondary emissions were analyzed using this model, and obviously differed from the primary emissions. The model is a useful tool for predicting, analyzing and “designing” the VOC emission characteristics, including secondary emissions, of building materials.
Volatile Organic Compounds in Uremia  [PDF]
Nikolaos Pagonas, Wolfgang Vautz, Luzia Seifert, Rafael Slodzinski, Joachim Jankowski, Walter Zidek, Timm H. Westhoff
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046258
Abstract: Background Although “uremic fetor” has long been felt to be diagnostic of renal failure, the compounds exhaled in uremia remain largely unknown so far. The present work investigates whether breath analysis by ion mobility spectrometry can be used for the identification of volatile organic compounds retained in uremia. Methods Breath analysis was performed in 28 adults with an eGFR ≥60 ml/min per 1.73 m2, 26 adults with chronic renal failure corresponding to an eGFR of 10–59 ml/min per 1.73 m2, and 28 adults with end-stage renal disease (ESRD) before and after a hemodialysis session. Breath analysis was performed by ion mobility spectrometryafter gas-chromatographic preseparation. Identification of the compounds of interest was performed by thermal desorption gas chromatography/mass spectrometry. Results Breath analyses revealed significant differences in the spectra of patients with and without renal failure. Thirteen compounds were chosen for further evaluation. Some compounds including hydroxyacetone, 3-hydroxy-2-butanone and ammonia accumulated with decreasing renal function and were eliminated by dialysis. The concentrations of these compounds allowed a significant differentiation between healthy, chronic renal failure with an eGFR of 10–59 ml/min, and ESRD (p<0.05 each). Other compounds including 4-heptanal, 4-heptanone, and 2-heptanone preferentially or exclusively occurred in patients undergoing hemodialysis. Conclusion Impairment of renal function induces a characteristic fingerprint of volatile compounds in the breath. The technique of ion mobility spectrometry can be used for the identification of lipophilic uremic retention molecules.
Influence of Precision of Emission Characteristic Parameters on Model Prediction Error of VOCs/Formaldehyde from Dry Building Material  [PDF]
Wenjuan Wei, Jianyin Xiong, Yinping Zhang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080736
Abstract: Mass transfer models are useful in predicting the emissions of volatile organic compounds (VOCs) and formaldehyde from building materials in indoor environments. They are also useful for human exposure evaluation and in sustainable building design. The measurement errors in the emission characteristic parameters in these mass transfer models, i.e., the initial emittable concentration (C0), the diffusion coefficient (D), and the partition coefficient (K), can result in errors in predicting indoor VOC and formaldehyde concentrations. These errors have not yet been quantitatively well analyzed in the literature. This paper addresses this by using modelling to assess these errors for some typical building conditions. The error in C0, as measured in environmental chambers and applied to a reference living room in Beijing, has the largest influence on the model prediction error in indoor VOC and formaldehyde concentration, while the error in K has the least effect. A correlation between the errors in D, K, and C0 and the error in the indoor VOC and formaldehyde concentration prediction is then derived for engineering applications. In addition, the influence of temperature on the model prediction of emissions is investigated. It shows the impact of temperature fluctuations on the prediction errors in indoor VOC and formaldehyde concentrations to be less than 7% at 23±0.5°C and less than 30% at 23±2°C.
Analyzing Method on Biogenic Volatile Organic Compounds
植物挥发性有机物的分析方法

Bai Jianhui,Wang Mingxing,Hu Fei,James P Greenberg,Alex B Guenther,
Bai Jianhui
,Wang Mingxing,Hu Fei,James P. Greenberg,Alex B. Guenther

大气科学进展 , 2002,
Abstract: In order to analyze biogenic volatile organic compounds in the atmosphere, an automated gas chromatography is developed and employed at the laboratory of National Center for Atmospheric Research (NCAR) during January to July, 2000. A small refrigerator was used so as to remove water in the air sample from gas line. and get accurate concentrations of volatile organic compounds. At 5°C, good water removing efficiency can be obtained at controlled flow rate. Air samples were collected around the building of Mesa Lab. of NCAR and analyzed by this gas chromatography system. This paper reports this gas chromatography system and results of air samples. The experimental results show that this gas chromatography system has a good reproducibility and stability, andmain interesting volatile organic compounds such as isoprene, monoterpenes have an evident diurnal variation.
The Primary Research on the Biogenic Volatile Organic Compounds
植物挥发性有机物的初步研究

Bai Jianhui,Wang Mingxing,Hu Fei,James PGreenberg,Alex BGuenther,
白建辉
,王明星,胡非,James P.Greenberg,Alex B.Guenther

气候与环境研究 , 2003,
Abstract: In order to analyze biogenic volatile organic compounds, a automatic gas chromatography(GC) and analyzing methods are developed and employed at the laboratory of National Center for Atmospheric Research (NCAR) during January to June 2000.Air samples were collected around the building of NCAR and analyzed by this GC system. The introduction for this GC system and results of air samples are given briefly.
Volatile Compounds of the Microalga Chlorella vulgaris and Their Phytotoxic Effect
Hanaa H. Abdel-Baky,M.A. Shallan,Gamal El- Baroty,F. K. El-Baz
Pakistan Journal of Biological Sciences , 2002,
Abstract: The volatile metabolites of green microalga, Chlorella vulgaris, grown under outdoor conditions were isolated by steam distillation and fractionated on a silica gel column using different organic solvent mixtures. The volatile metabolites and the individual fractions were analyzed using GLC and GC/MS. The volatile compounds were a mixture of 105 compounds of which 30 were identified. These components consisted of hydrocarbons, acids, alcohols, esters, aldehydes and ketones, having 33.67, 23.93, 15.62, 8.02, 3.24 and 2.71% of the total volatile components, respectively. The total volatile metabolites had strong inhibitory action on α-amylase activity and growth of the coleoptiles as well as the germination rate of barley grains. The acid fraction had a significantly higher phytotoxic effect in comparison with the other fractions and its action was mainly due to the presence of lionleic acid in this fraction. Hydrocarbon and polar fractions did not show any significant activity as phythotoxic agents.
Volatile compounds of functional dairy products
Ili?i? Mirela D.,Milanovi? Spasenija D.,Cari? Marijana ?.,Kanuri? Katarina G.
Acta Periodica Technologica , 2012, DOI: 10.2298/apt1243011i
Abstract: Volatile compounds, affecting flavour of traditional and probiotic fresh cheese, were determined. Functional dairy product-fresh cheese was produced from milk of 2.5% fat content and milk of 4.2% fat content, under the semi-industrial conditions. The traditional starter culture Flora Danica (FD) and a combination of probiotic starter ABT-1 and FD (ABT-1:FD=1:1) were applied as starters. The volatile fractions were isolated by employing the combined simultaneous distillation-extraction technique (SDE). The compounds were identified by gas chromatography - mass spectrometry (GC-MS) and quantified by using standard procedure. Following 19 compounds have been identified: 8 hydrocarbons (decane, undecane, tridecane, tetradecane, pentadecane, hexadecane, octadecane and 2, 6, 10, 14-tetramethyl hexadecane); 6 ketones (2-heptanone, 2-nonanone, 2- undecanone, 2-pentadecanone, 2-heptadecanone and 2-tridecanone); 3 aldehydes (nonanal, tetradecanal and hexadecanal); 1 fatty acid (decanoic acid) and disulfide, bis (1-methylethyl). The highest levels were associated with hexadecanal, 2-pentadecanone, 2-tridecanone, and 2-undecanone in all examined samples, regardless to the starter culture and type of milk used. [Projekat Ministarstva nauke Republike Srbije, br. 46009]
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