DOCSLIB.ORG

Dimensional Gas Chromatography

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dimensional Gas Chromatography Solid phase microextraction coupled to comprehensive two- dimensional gas chromatography–time-of-flight mass spectrometry for metabolite profiling of apples: Potential of non-invasive in vivo sampling assay in characterization of metabolome by Sanja Risticevic A thesis presented to the University of Waterloo in fulfillment of the thesis requirement for the degree of Doctor of Philosophy in Chemistry Waterloo, Ontario, Canada, 2012 Sanja Risticevic 2012 Author’s Declaration I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. ii Abstract The objective of the current research project relies on implementation of solvent-free, green and environmentally friendly solid phase microextraction (SPME) sample preparation alternative in the area of complex sample characterization. The advantages that the technique offers in comparison to traditional methods of sample preparation including solvent-free implementation, short sample preparation times, small sample amount requirements, advanced automation capability and minimization of matrix effects are effectively employed during ex vivo and laboratory investigations of complex samples. More important, the underlying features of the technique including miniaturized format, nonexhaustive extraction recoveries and on-site compatibility were fully exploited in order to investigate the metabolome of biological systems directly on the site. Hence, in vivo SPME extraction format was employed in direct immersion SPME sampling of biological systems, hence eliminating the crucial prerequisites associated with multiple preparative steps and incorporation of metabolism quenching that are encountered during implementation of traditional sample preparation methods in global metabolite analysis. Furthermore, in vivo sampling format was hyphenated to comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GCxGC-ToFMS) for high-resolution sampling of volatile and semivolatile metabolites in ‘Honeycrisp’ apples. The initial stages of the project involved evaluation of performance characteristics of commercial SPME extraction coatings in terms of extraction selectivity, extraction sensitivity and desorption efficiency by employing headspace SPME analysis of both aqueous standards spiked with representative volatile and semivolatile metabolites as well as the apple homogenate. DVB/CAR/PDMS coating was selected on the basis of optimum metabolite coverage and extraction sensitivity and was consequently employed during ex vivo and in vivo sampling assays corresponding to determination of volatile and iii semivolatile metabolites. The former extraction methodology incorporated appropriate sample preparation steps for quenching metabolic activity so that the relevant metabolome profile is not biased against unstable metabolites and those that are susceptible to inter-metabolite conversions which adversely impact preservation of metabolite identity. The two sample preparation assays were compared in terms of metabolite coverage and analytical precision in order to identify SPME route toward characterization of more representative metabolome and determination of instantaneous and more ‘true’ metabolism snapshoot. This is the first report illustrating the implementation of in vivo direct immersion SPME assay for non invasive determination of endogenous fruit metabolites whose profiles and contents are highly correlated to a multitude of influential fruit quality traits. iv Acknowledgements I am very grateful to many many people from University of Waterloo and external industrial and government organizations for completion of this wonderful project. First of all, I am thankful to my supervisor, Dr. Janusz Pawliszyn for giving me the opportunity to have such a wonderful and exciting PhD project, the project whose completion has not only been rewarding contribution to the field of analytical chemistry and his research group, but also has been important in extending the range of my own expertise. Throughout the years, I have been intensively and continuously learning new concepts from all possible dimensions that were composing my project, including sample preparation, in vivo SPME, comprehensive two-dimensional gas chromatography and time-of- flight mass spectrometry. I am proud of the extent of knowledge and level of excellence that I acquired during my PhD years and how much I have matured as a scientist and an analytical chemist during the period of my PhD program. Thank you professor Pawliszyn for giving me time to learn new methodology and to comprehensively investigate the effects of many experimental conditions and variables on the quality of the analytical method. Thank you so much, because I realize that my instrumental investigations not only made me learn and learn and learn but also resulted in the development of robust and high- quality SPME-GCxGC-ToFMS method that I am proud of and that has been impressing me on daily basis with acquisition of reliable data sets. I am also very grateful for the financial support that you offered, for the opportunity to engage and be responsible for SPME course coordination and organization, for having your support to participate in international meetings and conferences and for the assignment of laboratory manager role. Thank you for allowing me to be comprehensive and detailed, for trusting in reliability and accuracy of my results and for believing in me and my capabilities in encountering daily challenges. v I am also very grateful to my advisory committee member, Dr. Jennifer DeEll from Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) (Simcoe, ON, Canada) for allowing the access to representative and reliable metabolomics sample sets, for editing my manuscripts and giving me valuable feedback on improving my written thesis document. It was my pleasure to have Dr. Michael Chong on my advisory committee and I am grateful to him about discussions on differential metabolites and their uniqueness to ex vivo and in vivo SPME modes of sampling. It was my pleasure to have Dr. Wojciech Gabryelski, Dr. Simon Chuong and Dr. Hans-Gerd Janssen on my committee and I thank them for contributing to improvement of my written thesis document. I am thanking my committee members for providing the excellent feedback about the organization, quality and structure of my thesis, for indicating that my results were valuable to the field of analytical chemistry and for nominating my thesis for award. I would also like to acknowledge Mr. Olivier Niquette and Mr. Chris Warren from LECO (St. Joseph, MI, USA) for allowing the cost-effective addition of GCxGC-ToFMS instrument to our InFAReL laboratory to be employed in my PhD project. I am thankful for your support during installation, configuration and maintenance of the instrument during all the years of my PhD project. I am grateful to Mr. Olivier Niquette for listening about my research, for being interested in and enthusiastic about my results, and for spending long hours and days trying to resolve a particular instrumental problem in the light of me being able to proceed with experiments and to have a more reliable method. I am also very grateful to Mr. Chris Warren and Dr. Tomas Kovalczuk for approving and organizing my participation at EUROanalysis conference in Belgrade (Serbia, September 2011) as it was my pleasure to do so and to present my results on LECO Pegasus 4D GCxGC- ToFMS system. I am grateful to Mr. Len Sidisky from Supelco (Bellefonte, PA, USA) for providing Supelcowax second dimension column for second dimension separation on GCxGC-ToFMS system. Special acknowledgment and vi gratefulness goes to Dr. Jack Cochran from Restek (Bellefonte, PA, USA) for carefully listening to my concerns about retention time stability in second dimension and providing the column on which such challenges were overcome. The possibility of performing automated data processing and alignment of metabolites greatly enhanced the speed of processing and generation of data matrices compatible with subsequent multivariate analysis. I am thankful to personnel from Gerstel (Linthicum, MD, USA), including Mr. Edward Pfannkoch, Mr. Jim Daley and Mr. Tim Pence for configuration of MultiPurpose Sampler (MPS 2), for considering the issues with autosampler configuration a high priority and for helping resolve multiple problems with autosampler configuration, installation and operation in impressively efficient and timely manner. I thank the two hard working people in the chemistry department at University of Waterloo, Mr. Kenneth Gosselink and Mr. Matthew Sternbauer from Chem Stores for going out of their way many times to assist me in organizations and preparations for in vivo sampling. I thank Erica Silva, my coworker and friend for attending on-site sampling sessions and for being inspired by my project and the results I was acquiring. I will never forget how much your presence has meant to me. I thank you for being a good friend and a great listener. I thank my two very best ‘coworker’ friends and amazing coworkers, Dr. Dajana Vuckovic and Dr. Rosalba Vatinno, for unconditional support and friendship, for being always there, for enjoying the collaborative activities that we were involved in, and for constantly impressing me with their dedication, motivation, enthusiasm, positive energy, hard work and amazing research potential.
Load more

Recommended publications
  • Retention Indices for Frequently Reported Compounds of Plant Essential Oils
    Retention Indices for Frequently Reported Compounds of Plant Essential Oils V. I. Babushok,a) P. J. Linstrom, and I. G. Zenkevichb) National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA (Received 1 August 2011; accepted 27 September 2011; published online 29 November 2011) Gas chromatographic retention indices were evaluated for 505 frequently reported plant essential oil components using a large retention index database. Retention data are presented for three types of commonly used stationary phases: dimethyl silicone (nonpolar), dimethyl sili- cone with 5% phenyl groups (slightly polar), and polyethylene glycol (polar) stationary phases. The evaluations are based on the treatment of multiple measurements with the number of data records ranging from about 5 to 800 per compound. Data analysis was limited to temperature programmed conditions. The data reported include the average and median values of retention index with standard deviations and confidence intervals. VC 2011 by the U.S. Secretary of Commerce on behalf of the United States. All rights reserved. [doi:10.1063/1.3653552] Key words: essential oils; gas chromatography; Kova´ts indices; linear indices; retention indices; identification; flavor; olfaction. CONTENTS 1. Introduction The practical applications of plant essential oils are very 1. Introduction................................ 1 diverse. They are used for the production of food, drugs, per- fumes, aromatherapy, and many other applications.1–4 The 2. Retention Indices ........................... 2 need for identification of essential oil components ranges 3. Retention Data Presentation and Discussion . 2 from product quality control to basic research. The identifi- 4. Summary.................................. 45 cation of unknown compounds remains a complex problem, in spite of great progress made in analytical techniques over 5.
    [Show full text]
  • Effect of Enzymes on Strawberry Volatiles During Storage, at Different Ripeness
    Effect of Enzymes on Strawberry Volatiles During Storage, at Different Ripeness Level, in Different Cultivars and During Eating Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Gulsah Ozcan Graduate Program in Food Science and Technology The Ohio State University 2010 Thesis Committee: Sheryl Ann Barringer, Adviser W. James Harper John Litchfield 1 Copyright by Gülşah Özcan 2010 ii ABSTRACT Strawberry samples with enzyme activity and without enzyme activity (stannous chloride added) were measured for real time formation of lipoxygenase (LOX) derived aroma compounds after 5 min pureeing using selected ion flow tube mass spectrometry (SIFT-MS). The concentration of (Z)-3-hexenal and (E)-2-hexenal increased immediately after blending and gradually decreased over time while hexanal concentration increased for at least 5 min in ground strawberries. The formation of hexanal was slower than the formation of (Z)-3-hexenal and (E)-2-hexenal in the headspace of pureed strawberries. The concentration of LOX aldehydes and esters significantly increased during refrigerated storage. Damaging strawberries increased the concentration of LOX aldehydes but did not significantly affect the concentration of esters. The concentrations of many of the esters were strongly correlated to their corresponded acids and/or aldehydes. The concentration of LOX generated aldehydes decreased during ripening, while fruity esters increased. Different varieties had different aroma profiles and esters were the greatest percentage of the volatiles. The aroma release of some of the LOX derived aldehydes in the mouthspace in whole strawberries compared to chopped strawberries showed that these volatiles are formed in the mouth during chewing.
    [Show full text]
  • Original Paper Comparison of Volatile Compounds in 'Fuji' Apples in The
    _ Food Science and Technology Research, 23 (1), 79 89, 2017 Copyright © 2017, Japanese Society for Food Science and Technology doi: 10.3136/fstr.23.79 http://www.jsfst.or.jp Original paper Comparison of Volatile Compounds in ‘Fuji’ Apples in the Different Regions in China 1 2* 3 2 2 2 Ling QIN , Qin-Ping WEI , Wen-Huai KANG , Qiang ZHANG , Jian SUN and Song-Zhong LIU 1Department of Life Science, Hebei Normal University of Science and Technology, Qinhuangdao 066004 P. R. China 2Institute of Forestry & Pomology, Beijing Academy of Agriculture & Forestry Sciences,Beijing 100093 P.R. China 3College of Bioscience and Bioengineering, Hebei University of Science and Technology, Shijiazhuang 050018 P.R. China Received May 25, 2015 ; Accepted September 28, 2016 The characteristics of the volatiles from 43 ‘Fuji’ apples representing 14 different apple production regions in China were investigated using headspace-solid phase micro-extraction (HS-SPME) combined with gas chromatography–mass spectrometry (GC-MS). The results obtained from this experiment showed that sixty- four volatile compounds were identified in ‘Fuji’ apples collected from 43 counties in China. The major volatile compounds were identified as 2-methyl butyl acetate and hexyl acetate. The composition of volatiles and their contents in ‘Fuji’ apples varied in different regions. All of the ‘Fuji’ apple samples could be classified into the following groups using a principal component analysis of the volatiles: (1) apples with high concentrations of hexyl acetate and (Z)-3-hexenyl acetate,
    [Show full text]
  • Estimation of Hydrolysis Rate Constants of Carboxylic Acid Ester and Phosphate Ester Compounds in Aqueous Systems from Molecular Structure by SPARC
    Estimation of Hydrolysis Rate Constants of Carboxylic Acid Ester and Phosphate Ester Compounds in Aqueous Systems from Molecular Structure by SPARC R E S E A R C H A N D D E V E L O P M E N T EPA/600/R-06/105 September 2006 Estimation of Hydrolysis Rate Constants of Carboxylic Acid Ester and Phosphate Ester Compounds in Aqueous Systems from Molecular Structure by SPARC By S. H. Hilal Ecosystems Research Division National Exposure Research Laboratory Athens, Georgia U.S. Environmental Protection Agency Office of Research and Development Washington, DC 20460 NOTICE The information in this document has been funded by the United States Environmental Protection Agency. It has been subjected to the Agency's peer and administrative review, and has been approved for publication. Mention of trade names of commercial products does not constitute endorsement or recommendation for use. ii ABSTRACT SPARC (SPARC Performs Automated Reasoning in Chemistry) chemical reactivity models were extended to calculate hydrolysis rate constants for carboxylic acid ester and phosphate ester compounds in aqueous non- aqueous and systems strictly from molecular structure. The energy differences between the initial state and the transition state for a molecule of interest are factored into internal and external mechanistic perturbation components. The internal perturbations quantify the interactions of the appended perturber (P) with the reaction center (C). These internal perturbations are factored into SPARC’s mechanistic components of electrostatic and resonance effects. External perturbations quantify the solute-solvent interactions (solvation energy) and are factored into H-bonding, field stabilization and steric effects. These models have been tested using 1471 reliable measured base, acid and general base-catalyzed carboxylic acid ester hydrolysis rate constants in water and in mixed solvent systems at different temperatures.
    [Show full text]
  • Expanding the Modular Ester Fermentative Pathways for Combinatorial Biosynthesis of Esters from Volatile Organic Acids
    ARTICLE Expanding the Modular Ester Fermentative Pathways for Combinatorial Biosynthesis of Esters From Volatile Organic Acids Donovan S. Layton,1,2 Cong T. Trinh1,2,3 1 Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 2 BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, Tennessee 3 Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Tennessee; telephone: þ865-974-8121; fax: 865-974-7076; e-mail: [email protected] Biotechnol. Bioeng. 2016;113: 1764–1776. ABSTRACT: Volatile organic acids are byproducts of fermentative ß 2016 Wiley Periodicals, Inc. metabolism, for example, anaerobic digestion of lignocellulosic KEYWORDS: modular chassis cell; carboxylate; ester; acyl acetate; biomass or organic wastes, and are often times undesired inhibiting acyl acylate; ester fermentative pathway cell growth and reducing directed formation of the desired products. Here, we devised a general framework for upgrading these volatile organic acids to high-value esters that can be used as flavors, fragrances, solvents, and biofuels. This framework employs the acid-to-ester modules, consisting of an AAT (alcohol Introduction acyltransferase) plus ACT (acyl CoA transferase) submodule and an alcohol submodule, for co-fermentation of sugars and organic Harnessing renewable or waste feedstocks (e.g., switchgrass, corn acids to acyl CoAs and alcohols to form a combinatorial library of stover, agricultural residue, or municipal solid waste)
    [Show full text]
  • Assessment of Free and Immobilized Kefir Culture in Simultaneous
    LWT - Food Science and Technology 76 (2017) 67e78 Contents lists available at ScienceDirect LWT - Food Science and Technology journal homepage: www.elsevier.com/locate/lwt Assessment of free and immobilized kefir culture in simultaneous alcoholic and malolactic cider fermentations Anastasios Nikolaou a, Alex Galanis a, Maria Kanellaki b, Chrysoula Tassou c, * Konstantoula Akrida-Demertzi d, Yiannis Kourkoutas a, a Laboratory of Applied Microbiology and Biotechnology, Department of Molecular Biology & Genetics, Democritus University of Thrace, Alexandroupolis, GR-68100, Greece b Food Biotechnology Group, Section of Analytical Environmental and Applied Chemistry, Department of Chemistry, University of Patras, Patras, GR-26500, Greece c Institute of Technology of Agricultural Products, Hellenic Agricultural Organization DEMETER, 1 S. Venizelou Str, Lykovrissi, Athens, GR-14123, Greece d Laboratory of Food Chemistry and Technology, Department of Chemistry, University of Ioannina, Dourouti, Ioannina, GR-45110, Greece article info abstract Article history: The aim of the present study was to assess application of free or immobilized kefir culture on apple Received 30 March 2016 pieces and delignified cellulosic material (DCM) in simultaneous alcoholic and malolactic cider fer- Received in revised form mentations at a wide temperature range (5e45 C). Repeated batch fermentations were continued for 12 October 2016 higher than 7 months, showing a high operational stability of the systems and were completed in less Accepted 13 October 2016 than 24 h with immobilized cells on DCM at 37 C. Malic acid conversion up to 71.5% and ethanol Available online 15 October 2016 productivity values up to 56.9 g/(Ld) were recorded, which could be adopted by the industrial sector.
    [Show full text]
  • Phase Change Indicators for Subambient Temperatures
    II NASA CONTRACTOR REPORT 40 h ,-. ..../_,.,_..,.. - . ;:" ;'; _...,: -I e U PHASE CHANGE INDICATORS FOR SUBAMBIENT TEMPERATURES by D. R. Kasanof and E. Kimmel Prepared by i TEMPILO CORPORATION New York, N. Y. for LatzgZey Research Center NATIONALAERONAUTICS AND SPACE ADMINISTRATION WASHINGTON, D. C. MARCH 1970 ._ TECH LIBRARY KAFB, NM 00b0899 c-w, J NASA CR-1576 /PHASE CHANGE INDICATORS FOR SUBAMBIENT TEMPERATURES bL&~Q- By D. R. Kasanof and E. Kimmel Distribution of this report is provided in the interest of informationexchange. Responsibility for thecontents resides in the author or organization that prepared it. \ p- ' '\.prepared under ContractNO. L/.@&J31.-566by Luc.g9 "-.._--. TEMPILO CORPORATION New York, N.Y. for Langley Research Center NATIONAL AERONAUTICS AND SPACE ADMINISTRATION For sale by the Clearinghouse for Federal Scientific ond Technical Information Springfield,Virginia 22151 - CFSTI price $3.00 PHASE CIIANGE INDICATORS FOR SUBAMBIENTTEMPERATURES By D. R. Kasanof and E. Kinnnel TEMPIL" CORPORATION Forty candidate organic compounds were evaluated as possible fusible temperature indicators for use in the range -50°F to -150°F. Of these, thirty with melting points ranging from -37°F to -162°F were found to be useful as temperature indicators. Nine candidates were rejected because they did not yield opaque, crystalline coatings by any of the application procedures attempted. One candidate material was rejected because it proved to be unstable. Phase studies of several binary systems were also carried out. A number of application procedures were evaluated. An aerosol-spray procedure was adopted because it consistently yielded opaque coatings, was relatively simple to employ and could probably be adapted for use in the Langley Field test apparatus.
    [Show full text]
  • Comprehensive Mapping of Volatile Organic Compounds in Fruits
    International PhD Program in Biomolecular Sciences XXVII Cycle Comprehensive Mapping of Volatile Organic Compounds in Fruits Tutor Dr. Fulvio Mattivi Department of Food Quality and Nutrition, Fondazione Edmund Mach Advisor Prof. Vladimir Shulaev Department of Biological Sciences, University of North Texas Ph.D. Thesis of Manoj Shahaji Ghaste Department of Food Quality and Nutrition Fondazione Edmund Mach 2013-2014 This thesis is lovingly dedicated to my Mother. Her support, encouragement, belief and constant love have sustained me throughout my life. Declaration I, Manoj Shahaji Ghaste confirm that this is my own work and the use of all material from other sources has been properly and fully acknowledged. Thesis abstract Volatile organic compounds (VOCs) are the key aroma producers in fruits and sensory quality of fruits is widely determined by qualitative and quantitative composition of VOCs. The aroma of grape is a complex of hundreds of VOCs belonging to different chemical classes like alcohols, esters, acids, terpenes, aldehydes, furanones, pyrazines, isoprenoids and many more. VOCs play important role as they determine the flavor of grapes and wine made from it. The objective of this thesis is to study of VOCs through development of different mass spectrometry based analytical methodologies and its applications for the comprehensive investigation and construction of database of the VOCs in grapes. First part of the study was dedicated to generation of a database of grape VOCs through the screening of multiple grape varieties (n=124) representing different species, color and origin. The experiment was carried out using headspace solid-phase microextraction (HS-SPME) and gas chromatography mass spectrometry (GC-MS) based approach and according to metabolomics protocols.
    [Show full text]
  • Comprehensive Overview of Common E-Liquid Ingredients and How They Can Be Used to Predict an E-Liquid's Flavour Category
    Original research Tob Control: first published as 10.1136/tobaccocontrol-2019-055447 on 10 February 2020. Downloaded from Comprehensive overview of common e- liquid ingredients and how they can be used to predict an e- liquid’s flavour category Erna J Z Krüsemann ,1,2 Anne Havermans ,1 Jeroen L A Pennings,1 Kees de Graaf,2 Sanne Boesveldt,2 Reinskje Talhout1 10–14 ► Additional material is ABSTRact cigarette smoking. In line with this, the use and published online only. To view Objectives Flavours increase e- cigarette attractiveness marketing of e- liquid flavours that are appealing to please visit the journal online (http:// dx. doi. org/ 10. 1136/ and use and thereby exposure to potentially toxic smokers may contribute to public health benefits. tobaccocontrol- 2019- 055447). ingredients. An overview of e- liquid ingredients is needed However, flavours may also stimulate vaping among to select target ingredients for chemical analytical and non- users, in particular young people.15–17 This is 1 Centre for Health toxicological research and for regulatory approaches concerning, as e- cigarettes are not safe10 18 19 That Protection, Rijksinstituut voor aimed at reducing e- cigarette attractiveness. Using is, chemicals in e- cigarette emissions (eg, tobacco- Volksgezondheid en Milieu, Bilthoven, The Netherlands information from e- cigarette manufacturers, we aim to specific nitrosamines, metals, aldehydes and other 2Division of Human Nutrition identify the flavouring ingredients most frequently added flavourings) can be toxic and thus harmful to and Health, Wageningen to e- liquids on the Dutch market. Additionally, we used consumers’ health.20–22 In addition, e- cigarettes University, Wageningen, The flavouring compositions to automatically classify e-liquids may facilitate smoking initiation among never- Netherlands into flavour categories, thereby generating an overview smokers.23 As a consequence, e- liquid flavours are that can facilitate market surveillance.
    [Show full text]
  • These Two Workbooks Are Provided by As a Convenient Introduc
    These two workbooks are provided by www.hansen-solubility.com as a convenient introduc They are Copyright © 2013 Prof Steven Abbott If you find bugs/issues or would like extra functionality, please email Steven Abbott [email protected] ction to some of the basic HSP methods HSP Sphere dD dP dH R Good 11 18.4 9.7 8.0 7.1 Bad 11 Test Value 16 7 8 Total 22 Delta 2.4 11.4 10.4 Distance 5.5 RED 0.77 Solvents dD dP dH MVol Score Distance Acetone 15.5 10.4 7 73.8 1 5.915773 Acetonitrile 15.3 18 6.1 52.9 0 10.52754 n-Amyl Acetate 15.8 3.3 6.1 148 0 n-Amyl Alcohol 15.9 5.9 13.9 108.6 0 Benzene 18.4 0 2 52.9 0 11.38507 Benzyl Alcohol 18.4 6.3 13.7 103.8 0 Benzyl Benzoate 20 5.1 5.2 190.3 0 1-Butanol 16 5.7 15.8 92 0 2-Butanol 15.8 5.7 14.5 92 0 n-Butyl Acetate 15.8 3.7 6.3 132.6 0 t-Butyl Acetate 15 3.7 6 134.8 0 t-Butyl Alcohol 15.2 5.1 14.7 96 0 Butyl Benzoate 18.3 5.6 5.5 178.1 0 Butyl Diglycol Acetate 16 4.1 8.2 208.2 0 Butyl Glycol Acetate 15.3 7.5 6.8 171.2 0 n-Butyl Propionate 15.7 5.5 5.9 149.3 0 Caprolactone (Epsilon) 19.7 15 7.4 110.8 0 Chloroform 17.8 3.1 5.7 80.5 1 7.075453 m-Cresol 18.5 6.5 13.7 105 1 6.563973 Cyclohexane 16.8 0 0.2 108.9 0 12.82752 Cyclohexanol 17.4 4.1 13.5 105.7 0 Cyclohexanone 17.8 8.4 5.1 104.2 0 Di-isoButyl Ketone 16 3.7 4.1 177.4 0 Diacetone Alcohol 15.8 8.2 10.8 124.3 0 Diethyl Ether 14.5 2.9 4.6 104.7 0 10.87429 Diethylene Glycol Monobut 16 7 10.6 170.4 0 Dimethyl Cyclohexane 16.1 0 1.1 140 0 Dimethyl Sulfoxide (DMSO) 18.4 16.4 10.2 71.3 1 7.066692 1,4-Dioxane 17.5 1.8 9 85.7 0 8.160898 1,3-Dioxolane
    [Show full text]
  • Interagency Committee on Chemical Management
    DECEMBER 14, 2018 INTERAGENCY COMMITTEE ON CHEMICAL MANAGEMENT EXECUTIVE ORDER NO. 13-17 REPORT TO THE GOVERNOR WALKE, PETER Table of Contents Executive Summary ...................................................................................................................... 2 I. Introduction .......................................................................................................................... 3 II. Recommended Statutory Amendments or Regulatory Changes to Existing Recordkeeping and Reporting Requirements that are Required to Facilitate Assessment of Risks to Human Health and the Environment Posed by Chemical Use in the State ............................................................................................................................ 5 III. Summary of Chemical Use in the State Based on Reported Chemical Inventories....... 8 IV. Summary of Identified Risks to Human Health and the Environment from Reported Chemical Inventories ........................................................................................................... 9 V. Summary of any change under Federal Statute or Rule affecting the Regulation of Chemicals in the State ....................................................................................................... 12 VI. Recommended Legislative or Regulatory Action to Reduce Risks to Human Health and the Environment from Regulated and Unregulated Chemicals of Emerging Concern ..............................................................................................................................
    [Show full text]
  • Dependent Modeling Approach Derived from Semi-Empirical Quantum Mechanical Calculations
    3D-QSAR/QSPR Based Surface- Dependent Modeling Approach Derived From Semi-Empirical Quantum Mechanical Calculations 3D-QSAR/QSPR-basierter, oberflächenabhängiger Modellierungsansatz, abgeleitet von semi-empirischen quantenmechanischen Rechnungen Der Naturwissenschaftlichen Fakultät der Friedrich-Alexander-Universität Erlangen-Nürnberg Zur Erlangung des Doktorgrades Dr. rer. nat. vorgelegt von Marcel Youmbi Foka aus Kamerun Als Dissertation genehmigt von der Naturwissenschaftlichen Fakultät/ vom Fachbereich Chemie und Pharmazie der Friedrich-Alexander-Universität Erlangen-Nürnberg Tag der mündlichen Prüfung: 05.12.2018 Vorsitzender des Promotionsorgans: Prof. Dr. Georg Kreimer Gutachter/in: Prof. Dr. Tim Clark Prof. Dr. Birgit Strodel Dedication In memory of my late Mother Lucienne Metiegam, who the Lord has taken unto himself on May 3, 2009. My mother, light of my life, God rest her soul, had a special respect for my studies. She had always encouraged me to move forward. I sincerely regret the fact that today she cannot witness the culmination of this work. Maman, que la Terre de nos Ancêtres te soit légère! This is a special reward for Mr. Joseph Tchokoanssi Ngouanbe, who always supported me financially and morally. That he find here the expression of my deep gratitude. i ii Acknowledgements I would like to pay tribute to all those who have made any contribution, whether scientific or not, to help carry out this work. All my thanks go especially to Prof. Dr. Tim Clark, who gave me the opportunity and means to work in his research team. I am grateful to have had him not only supervise my work but also for his patience and for giving me the opportunity to explore this fascinating topic.
    [Show full text]