DOCSLIB.ORG

Analyses on Condom Evidence: Condom Brand Profiling Via HS-SPME-GC-MS and Temperature-Brand Effect on Condom Fingerprint Development

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Analyses on Condom Evidence: Condom Brand Profiling Via HS-SPME-GC-MS and Temperature-Brand Effect on Condom Fingerprint Development Analyses on condom evidence: Condom brand profiling via HS-SPME-GC-MS and temperature-brand effect on condom fingerprint development by Amanda Patrick, B.S. A Thesis In Forensic Sciences Submitted to the Graduate Faculty of Texas Tech University in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCES Approved Paola Prada, Ph. D. Chair of Committee Kathy Sperry, Ph. D. Megan Thoen, Ph. D. Mark Sheridan, Ph. D. Dean of the Graduate School December, 2018 © 2018, Amanda Patrick Texas Tech University, Amanda Patrick, December 2018 Acknowledgments The authors of this study would like to thank the participants who made this study possible. ii Texas Tech University, Amanda Patrick, December 2018 TABLE OF CONTENTS ABSTRACT ................................................................................................................................... vi LIST OF TABLES ...................................................................................................................... viii LIST OF FIGURES ...................................................................................................................... ix LIST OF ABREVIATIONS ......................................................................................................... xi 1. Introduction ............................................................................................................................ 1 1.1.Statement of Objectives ........................................................................................................ 2 1.1.1. Fingerprints on Condoms ......................................................................................... 2 1.1.2. Condom Brand Identification................................................................................... 3 2. Literature Review .................................................................................................................. 5 2.1.Impact of Evidence in Sexual Assault Cases ....................................................................... 5 2.1.1. Limitations in Investigation ..................................................................................... 6 2.1.2. Forensic Evidence .................................................................................................. 16 2.2.Basic Condom Production .................................................................................................. 22 2.3.Substrate effect on Fingerprint Development .................................................................. 23 2.3.1. Challenging Substrates ........................................................................................... 24 2.3.2. Variation of Developmental Methods .................................................................... 24 2.3.3. Challenges with Single Types of Substrates .......................................................... 27 2.3.4. Environmental Conditions & Development with Powders .................................... 31 2.4.Chemical Characterization of Condoms ........................................................................... 32 2.4.1. Previous Methods Used for Identifying Condom Brands and Lubricants ............. 32 2.4.2. Gas Chromatography-Mass Spectrometry ............................................................. 35 2.4.3. Solid Phase Microextraction .................................................................................. 39 2.4.4. SPME and Plastics ................................................................................................. 42 2.4.5. Principle Component Analysis............................................................................... 46 2.5.Hypotheses ........................................................................................................................... 49 2.5.1. Temperature Variation on Fingerprint Development ............................................. 49 2.5.2. Condom Brand Identification................................................................................. 50 3. Methods ................................................................................................................................. 52 3.1.Temperature Effect on Fingerprint Development ........................................................... 52 iii Texas Tech University, Amanda Patrick, December 2018 3.1.1. Materials ................................................................................................................ 52 3.1.2. Experimental Procedures ....................................................................................... 53 3.1.3. Inter-person Variability .......................................................................................... 57 3.1.4. Dye Staining ─ Rhodamine 6G ............................................................................. 58 3.2.Condom Brand Identification using HS-SPME ............................................................... 58 3.2.1. Materials and Standard Instrumental Procedures ................................................... 58 3.2.2. Experimental Procedures ....................................................................................... 60 3.3.Data Collection and Analyses ............................................................................................. 63 3.3.1. Condom Brand SPME Profiling ............................................................................ 63 3.3.2. Fingerprint Development ─ Temperature Effect ................................................... 63 4. Results ................................................................................................................................... 64 4.1.Temperature-Brand Effect on Fingerprint Development ............................................... 64 4.1.1. Magnetic Powder ................................................................................................... 64 4.1.2. Inter-person Variability ─ Magnetic Powder ......................................................... 67 4.1.3. Rhodamine 6G ....................................................................................................... 69 4.1.4. Inter-person Variability-Rhodamine 6G ................................................................ 73 4.2.Condom Brand Identification via HS-SPME-GC-MS ..................................................... 75 4.2.1. Fiber and Sampling Time ....................................................................................... 75 4.2.2. Brand identification ............................................................................................... 78 5. Discussion ............................................................................................................................. 82 5.1.Temperature analysis on Fingerprint Development ........................................................ 82 5.2.Identification of Condom Brands ...................................................................................... 85 5.3.Conclusion ............................................................................................................................ 88 References ..................................................................................................................................... 91 Appendix I: Photographs and Scores of Developed Fingerprints ........................................... 98 Magnetic Power ......................................................................................................................... 99 15ºC ............................................................................................................................... 99 24ºC ............................................................................................................................. 101 40ºC ............................................................................................................................. 103 iv Texas Tech University, Amanda Patrick, December 2018 Magnetic Powder ─ Population ............................................................................................. 106 Rhodamine 6G ......................................................................................................................... 111 15ºC ............................................................................................................................. 111 24ºC ............................................................................................................................. 113 40ºC ............................................................................................................................. 115 Rhodamine 6G ─ Population ................................................................................................. 118 Appendix II: Compound Data and Chromatograms .............................................................. 123 v Texas Tech University, Amanda Patrick, December 2018 ABSTRACT Condoms are a challenging substrate as an evidentiary item since they do not hold a determined shape and fundamental composition may vary depending on the brand. Developmental variables in regard to condoms substrates were investigated to optimize latent print methodologies. Fingerprints were deposited onto condoms of various brands, exposed to different temperatures, and developed with superglue fuming, magnetic powder, and Rhodamine 6G (R6G). For magnetic powder, results indicated that the highest average fingerprint score was obtained on condoms stored in 15°C temperatures.
Load more

Recommended publications
  • Chapter 1 Tropone and Tropolone
    School of Molecular and Life Sciences New Routes to Troponoid Natural Products Jason Matthew Wells This thesis is presented for the Degree of Doctor of Philosophy of Curtin University November 2018 Declaration To the best of my knowledge and belief this thesis contains no material previously pub- lished by any other person except where due acknowledgement has been made. This thesis contains no material which has been accepted for the award of any other degree or diploma in any other university. Signature: Date: i Abstract Malaria is an infectious disease found in humans and other animals, it is caused by a single-cell parasite of the Plasmodium genus with many different substrains. Of these, P. falciparum is the most deadly to humans causing the majority of deaths. Although research into the area of antimalarial compounds is wide spread, few have been devel- oped with new structural features. Cordytropolone 37 is a natural product isolated in 2001 from the insect pathogenic fungus Cordyceps sp. BCC 1681 and has been shown to have antimalarial activity against P. falciparum. It has a structure unrelated to antimalarial com- pounds currently used in therapy. It does not contain a peroxide bridge as with artemisinin 25 or quinoline rings as with chloroquine 22. This unique structure indicates that it could possibly interact with the malaria parasite in a fashion unlike current treatments. In order for cordytropolone to be further developed as a potential treatment, it must first be synthe- sised in a laboratory environment. This study attempts to develop the first total synthesis of cordytropolone. H HO O N O O N O N H H H O O Cl HO O 22 25 37 Figure 0.0.1: Cordytropolone 37 has a unique structure compared to the current common malaria treatments The first method investigated towards the total synthesis of cordytropolone involved an intramolecular Buchner ring expansion.
    [Show full text]
  • Page 1 of 43 RSC Advances
    RSC Advances This is an Accepted Manuscript, which has been through the Royal Society of Chemistry peer review process and has been accepted for publication. Accepted Manuscripts are published online shortly after acceptance, before technical editing, formatting and proof reading. Using this free service, authors can make their results available to the community, in citable form, before we publish the edited article. This Accepted Manuscript will be replaced by the edited, formatted and paginated article as soon as this is available. You can find more information about Accepted Manuscripts in the Information for Authors. Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal’s standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains. www.rsc.org/advances Page 1 of 43 RSC Advances Sol-gel based simonkolleite nanopetals with SnO2 nanoparticles in graphite-like amorphous carbon as efficient and reusable photocatalyst Moumita Pal, Susanta Bera and Sunirmal Jana* Sol-Gel Division CSIRCentral Glass and Ceramic Research Institute (CSIRCGCRI) 196 Raja S.C. Mullick Road, P.O. Jadavpur University, Kolkata 700032, India Abstract We report a new sol-gel nanocomposite (STC) having simonkolleite nanopetals (SC) and quasi-spherical tin oxide (SO) nanoparticles embedded in graphite-like amorphous carbon (C) as an efficient and reusable photocatalyst towards degradation of Rhodamine 6G (Rh 6G) dye under UV (, 254 nm) illumination.
    [Show full text]
  • Synthesis and Characterization of Ph-Sensitive Rhodamine 6G Spirolactam Structures
    W&M ScholarWorks Undergraduate Honors Theses Theses, Dissertations, & Master Projects 5-2015 Synthesis and Characterization of pH-Sensitive Rhodamine 6G Spirolactam Structures Grace H. Taumoefolau Follow this and additional works at: https://scholarworks.wm.edu/honorstheses Part of the Organic Chemistry Commons, and the Other Chemistry Commons Recommended Citation Taumoefolau, Grace H., "Synthesis and Characterization of pH-Sensitive Rhodamine 6G Spirolactam Structures" (2015). Undergraduate Honors Theses. Paper 220. https://scholarworks.wm.edu/honorstheses/220 This Honors Thesis is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Undergraduate Honors Theses by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. Table of Contents Page Table of Contents ii List of Figures and Tables iii Abstract 5 Acknowledgements 6 Introduction 8 Results and Discussion Chapter I: Optimization of R6G derivatives Reaction Conditions 14 Chapter II: Characterization of di-ortho R6G Derivatives 30 Chapter III: Attempt at achieving RB and R6G FRET 44 Experimental 57 References 66 Appendix 68 List of Figures and Tables Page Figure 1 Jablonski Diagram of Fluorescence 9 Figure 2 Fluorescence Excitation (Absorption) and Emission Spectra 9 Figure 3 Rhodamine B and Rhodamine 6G 10 Figure 4 Yuan’s RSL compounds ethanol and adamantyl substituted R6G 11 Figure 5 Rhodamine 6G with the functional group at the upper ring system altered from an ethyl acetate to a carboxylic acid (shorthand, R6G-acid) 15 Figure 6 R6G-Acid salt, with the quaternary ammonium cation at the xanthene core 17 Figure 7 Aromatic region in the NMR of R6G-dMA before the alumina column 26 Figure 8 Aromatic region in the NMR of R6G-dMA byproduct 26 Figure 9 An example of an oxidized amine due to alumina 27 Figure 10 NMR spectra of R6G-aniline.
    [Show full text]
  • Polarized Stimulated Emission Depletion Studies of Two-Photon Excited States
    Polarised Stimulated Emission Depletion Studies of Two-Photon Excited States D. A. Armoogum, R. J. Marsh and A. J. Bain+ Department of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, UK ABSTRACT Stimulated emission depletion (STED) population and polarisation dynamics following two-photon excitation are investigated for rhodamine 6G in ethylene glycol. Time resolved fluorescence intensity and polarisation measurements were made using picosecond time-correlated single photon counting (TCSPC). Cross-sections for the stimulated transition were measured between 614nm (2.32×10-16 cm2) and 663.5nm (6.05×10 –17 cm2), ground state vibrational lifetimes were found to vary between 314fs and 467fs. A collinear (180°) excitation-detection geometry was employed to investigate re-polarisation of the excited state array yielding fluorescence anisotropies above the two-photon limit. The circumvention of single-photon selection rules is demonstrated allowing the measurement of higher order parameters and correlation functions that are wholly inaccessible to ‘conventional’ (spontaneous) time resolved fluorescence techniques. Key words: Stimulated emission depletion, vibrational relaxation, two-photon, polarisation, selection rules. 1. INTRODUCTION Stimulated emission depletion (STED) of excited states has proved to be both a valuable tool in high resolution molecular spectroscopy1, in time resolved spectroscopy as a means of orientational photoselection2 and in the study of ultrafast vibrational relaxation within electronic ground states3. There has been considerable interest in the use of single- photon STED in fluorescence microscopy4 where sub-wavelength image resolution has been recently demonstrated5. Recent work in our laboratory6,7 has demonstrated the feasibility of performing STED in two-photon excited states. In this work femtosecond two-photon 800nm excitation (PUMP) of the widely used fluorescent probe fluorescein was followed by picosecond stimulated emission depletion (DUMP) of the excited state at 580nm.
    [Show full text]
  • Rhodamine 6G*
    2150 Bixby Road Lockbourne, OH 43137 Tel: 614.492.5610 E-mail: [email protected] www.exciton.luxottica.com Rhodamine 6G* Synonym: 2-[6-(ethylamino)-3-(ethylimino)-2,7-dimethyl-3H-xanthen-9-yl]-benzoic acid, ethyl ester, chloride or or perchlorate; Basic Red 1 (Rhodamine 6G = ethyl ester; Rhodamine 590 = methyl ester; to the best of our knowledge, the two esters have equivalent performance) Catalog No.: 05906 (chloride); 05905 (perchlorate) CAS No.: 989-38-8 (05906); 13161-28-9 (05905) MW: 479.02 (05906); 543.01 (05905) Chemical Formula: C28H31ClN2O3 (05906); C28H31N2O3.ClO4 (05905) Appearance: Red solid (05906); red to violet (05905) Molar Absorptivity (in ethanol): 9.70 x 104 L mole-1 cm-1 (chloride form) Structure: + C2H5NH O NHC2H5 X- CO2Et X = Cl- or ClO - 4 Lasing Wavelength Laser Dye Max. Range Pump Source Concentration Abs Fl Catalog No. (nm) (nm) (nm) Solvent (molar) -max -max ___________________________________________________________________________________________________________ Rhodamine 6G 578 565-612 FL3 Methanol 5 x 10-5 530e 556e (Available as 584 570-618 FL3 Ethanol 5 x 10-5 the Chloride, 585 562-622 FL69 Methanol 4 x 10-5 Cl, 05906; the 586 563-625 FL11 Methanol 5 x 10-5 Perchlorate, 590 FL63 Methanol 8 x 10-5 69 ClO4, 05905) 596 577-614 FL MeOH/H2O,1/3 12 -4 598 577-625 FL MeOH/H2O,1/1 1.3 x 10 188 -4 590-610 FL -cyclodextrin/H2O 2.3 x 10 63 -4 600 FL 4% LO/H2O 1.2 x 10 12 -4 610 585-633 FL 4% LO/H2O 1.3 x 10 606 FL (Triaxial) 227 Acrylic Copolymer 1 x 10-4 580 KrF(248)44 Ethanol 1 x 10-3 590 KrF(248)46
    [Show full text]
  • CH Functionalization Via Iron-Catalyzed Carbene
    molecules Review C-H Functionalization via Iron-Catalyzed Carbene-Transfer Reactions Claire Empel, Sripati Jana and Rene M. Koenigs * Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany; [email protected] (C.E.); [email protected] (S.J.) * Correspondence: [email protected] Academic Editor: Hans-Joachim Knölker Received: 4 January 2020; Accepted: 5 February 2020; Published: 17 February 2020 Abstract: The direct C-H functionalization reaction is one of the most efficient strategies by which to introduce new functional groups into small organic molecules. Over time, iron complexes have emerged as versatile catalysts for carbine-transfer reactions with diazoalkanes under mild and sustainable reaction conditions. In this review, we discuss the advances that have been made using iron catalysts to perform C-H functionalization reactions with diazoalkanes. We give an overview of early examples employing stoichiometric iron carbene complexes and continue with recent advances in the C-H functionalization of C(sp2)-H and C(sp3)-H bonds, concluding with the latest developments in enzymatic C-H functionalization reactions using iron-heme-containing enzymes. Keywords: iron; carbene; diazoalkane; C-H functionalization 1. Introduction C-H bonds belong to the most common motifs in organic molecules and their direct functionalization is one of the main challenges in synthesis methodology, which impacts on the step economy and sustainability of chemical processes. In recent decades, this research area has flourished and different approaches have been realized to enable C-H functionalization reactions via different strategies: (a) by the directing group-assisted C-H activation, (b) via the innate reactivity of organic molecules, or (c) via direct C-H functionalization (Scheme1)[ 1–4].
    [Show full text]
  • Time-Resolved Spectra of Coumarin 30-Rhodamine 6G Dye Mixture
    Pram~n.a - J. Phys., Vol. 34, No. 1, January 1990, pp. 77-83. © Printed in India. Time-resolved spectra of coumarin 30-rhodamine 6G dye mixture R D SINGH, D MOHAN, A K SHARMA and N V UNNIKRISHNAN* Department of Physics, Maharshi Dayanand University, Rohtak 124001, India *Department of Material Science, Mahatma Gandhi University, Kottayam 686 562, India MS received 9 March 1989; revised 30 September 1989 Abstract. The effect of acceptor concentration on the energy transfer from Coumarin 30 (donor) to Rhodamine 6G (acceptor) has been studied. The nature of energy transfer reaction has been studied through lifetime measurements by recording the time-resolved fluorescence decay curves. The energy transfer parameters calculated were used to confirm the occurrence of energy transfer on the basis of the emission-reabsorption effect. Keywords. Time-resolved spectra; energy transfer; fluorescence; Coumarin-Rhodamine mixture. PACS No. 42"55 1. Introduction Excitation transfer in laser dye mixtures has earlier been used to achieve better dye laser performance at the desired wavelengths (Morey 1972; Drake et al 1972; Cox and Matise 1980; Berlman et al 1973). The mechanism responsible for the intermolecular singlet-singlet electronic energy transfer in dye mixture can be directly determined by lifetime measurements. The studies so far reported in this field have been based on the indirect method of optical gain studies. We have studied the energy transfer mechanism in coumarin 30-rhodamine 6G (C 30-Rh 6G) dye mixture in ethanol by using a laser fluorimeter developed in the laboratory. The dependence of lifetime on dye concentration of the two dye molecules C 30 and Rh 6G in alcoholic solutions of methanol and ethanol, and ethylene glycol has also been studied.
    [Show full text]
  • Towards the Synthesis of Isocoronene
    Department of Chemistry Towards the Synthesis of Isocoronene Iain William Currie This thesis is presented for the Degree of Doctor of Philosophy of Curtin University April 2018 Declaration To the best of my knowledge and belief this thesis contains no material previously published by any other person except where due acknowledgement has been made. This thesis contains no material which has been accepted for the award of any other degree or diploma in any other university. Signature: Date: i Abstract The concept of aromaticity and its implications are fundamentally important to a wide range of applied sciences involving organic molecules. Aromaticity arises from the delocalisation of electrons through a cyclic conjugated system known as a conjugated circuit. Monocyclic aromatic compounds possess a single conjugated circuit while polycyclic aromatic hydrocarbons (PAHs) may have numerous potential conjugated circuits. The aromaticity of PAHs is complicated by the presence of multiple conjugated circuits which may have varying contribution to the overall properties depending on several factors such as geometry and topology. Isocoronene 105 is one example of a PAH classified as a non-benzenoid corannulene. Isocoronene is unique among corannulenes since the conjugated circuits are restricted to the peripheral and central rings only. Isocoronene has been used as a model compound for computational studies into aromaticity and may provide the first example of a superaromatic molecule. The synthesis of novel aromatic structures such as isocoronene is essential in providing unambiguous empirical data which can be used to verify and develop computational methods. In addition, the development of new synthetic methodologies towards PAHs is important in the field of organic electronics.
    [Show full text]
  • Potent Fluorescent Probes of Mitochondria in Living C. Elegans
    ydrophobic analogues of rhodamine B and rhodamine 101: potent fluorescent probes of mitochondria in living . elegans Laurie F. Mottram1, Safiyyah Forbes1, Brian D. Ackley! and Blake R. Peterson*1 Full Research Paper Open Access Address: !eilstein J. Org. Chem. 2012, 8, 156–165. 1Department of Medicinal Chemistry, The University of Kansas, doi:10.376/bjoc.8.43 Lawrence, KS 66045, United States and !Department of Molecular Biosciences, The University of Kansas, Lawrence, KS 66045, United Received: 9 September 01 States Accepted: 09 November 01 Published: 11 December 01 Email: Blake R. Peterson* - [email protected] This article is part of the Thematic Series "Synthetic probes for the study of biological function". * Corresponding author Guest Editor: J. Aube Keywords: Caenorhabditis elegans; chemical biology; fission; fluorophores; © 01 Mottram et al; licensee Beilstein-Institut. fluorescence; fusion; imaging; in vivo; microscopy; mitochondria; License and terms: see end of document. model organisms; organelle; rhodamine; spectroscopy Abstract itochondria undergo dynamic fusion and fission events that affect the structure and function of these critical energy-producing cellular organelles. Defects in these dynamic processes have been implicated in a wide range of human diseases including ischemia, neurodegeneration, metabolic disease, and cancer. To provide new tools for imaging of mitochondria in vivo, we synthesized novel hydrophobic analogues of the red fluorescent dyes rhodamine B and rhodamine 101 that replace the carboxylate with a methyl group. Compared to the parent compounds, methyl analogues termed HRB and HR101 exhibit slightly red-shifted absorbance and emission spectra (5–9 nm), modest reductions in molar extinction coefficent and quantum yield, and enhanced partitioning into octanol compared with aqueous buffer of 10-fold or more.
    [Show full text]
  • Chemotherapeutic Applications of Rhodamine Based Nanogumbos
    Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 3-2-2018 Chemotherapeutic Applications of Rhodamine Based NanoGUMBOS Nimisha Bhattarai Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Analytical Chemistry Commons Recommended Citation Bhattarai, Nimisha, "Chemotherapeutic Applications of Rhodamine Based NanoGUMBOS" (2018). LSU Doctoral Dissertations. 4499. https://digitalcommons.lsu.edu/gradschool_dissertations/4499 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. CHEMOTHERAPEUTIC APPLICATIONS OF RHODAMINE BASED NANOGUMBOS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Chemistry by Nimisha Bhattarai B.S. University of Central Missouri, 2013 May 2018 To my mentor, Prof. Warner, thank you so much for your endless support, insightful guidance and inspiration for my future endeavors. ii AKNOWLEDGEMENTS I want to sincerely thank everyone that has supported me throughout my graduate school, especially the following: Prof. Isiah M. Warner, thank you for all of your guidance, encouragement and support throughout this research and all of the inspiration and motivation for my future endeavors Doctoral Committee Members: Prof. Doug Gilman, Prof. Kermit Murray, Prof. Megan Macnaughtan, and Prof. Kevin McCarter for their guidance and suggestions as my committee members.
    [Show full text]
  • University Microfilm S International
    INFORMATION TO USERS This material was produced from a microfilm copy of the original document. While the most advanced technological means to photograph and reproduce this document have been used, the quality is heavily dependent upon the quality of the original submitted. The following explanation of techniques is provided to help you understand markings or patterns which may appear on this reproduction. 1.The sign or "target" for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting thru an image and duplicating adjacent pages to insure you complete continuity. 2. When an image on the film is obliterated with a large round black mark, it is an indication that the photographer suspected that the copy may have moved during exposure and thus cause a blurred image. You will find a good image of the page in the adjacent frame. 3. When a map, drawing or chart, etc., was part of the material being photographed the photographer followed a definite method in "sectioning" the material. It is customary to begin photoing at the upper left hand corner of a large sheet and to continue photoing from left to right in equal sections with a small overlap. If necessary, sectioning is continued again — beginning below the first row and continuing on until complete. 4. The majority of users indicate that the textual content is of greatest value, however, a somewhat higher quality reproduction could be made from "photographs" if essential to the understanding of the dissertation.
    [Show full text]
  • Decomposition of Ruthenium Olefin Metathesis Catalyst
    catalysts Review Decomposition of Ruthenium OlefinOlefin Metathesis CatalystMetathesis Catalyst Magdalena Jawiczuk 1,, Anna Anna Marczyk Marczyk 1,21,2 andand Bartosz Bartosz Trzaskowski Trzaskowski 1,* 1,* 1 1 CentreCentre of of New New Technologies, Technologies, University University of of Warsaw, Warsaw, Banacha Banacha 2c, 2c, 02-097 02-097 Warsaw, Warsaw, Poland; [email protected]@cent.uw.edu.pl (M.J.); (M.J.); [email protected] [email protected] (A.M.) (A.M.) 2 Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland 2 Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland * Correspondence: [email protected] * Correspondence: [email protected] Received: 28 28 June 2020; Accepted: 02 2 AugustAugust 2020;2020; Published:Published: 5date August 2020 Abstract: RutheniumRuthenium olefin olefin metathesis metathesis catalysts catalysts are are one one of of the most commonly used class of catalysts. There There are are multiple multiple reviews reviews on on their their us useses in in various branches of chemistry and other sciences but a detailed review of their decomposition is missing, despite a large number of recent and important advances advances in in this this field. field. In In particular, particular, in in the the last last five five years years several several new new mechanism mechanism of decomposition,of decomposition, both both olefin-driven olefin-driven as well as well as induc as induceded by external by external agents, agents, have have been been suggested suggested and usedand usedto explain to explain differences differences in the decomposition in the decomposition rates and rates the metathesis and the metathesis activities activitiesof both standard, of both N-heterocyclicstandard, N-heterocyclic carbene-based carbene-based systems and systems the recently and the developed recently developed cyclic alkyl cyclic amino alkyl carbene- amino containingcarbene-containing complexes.
    [Show full text]