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Cvikýřová, Zuzana. "Ekotoxicita vybraných musk sloučenin". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2012. http://www.nusl.cz/ntk/nusl-216854.
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Products of daily use, which are mainly cosmetics and personal care products could significantly affect the environment. Recently, in terms of environmental protection, organic compounds responsible for the pleasant smell of these products - synthetic fragrances or musk compounds - are often mentioned. This diploma thesis aims to assess the ecotoxicity of several new substances from the group linear (alicyclic) musk compounds. From this group following fragrance ingrediens were tested: lilial, linalool, arocete and aroflorone. Since the majority of their residues enter the aquatic ecosystem, aquatic freshwater crustacean Daphnia magna and Thamnocephalus platyurus and aquatic plant Lemna minor were selected as test organisms. Individual ecotoxicity of above mentioned substances was evaluated as well as toxicity of binary mixture of arofloron and linalool on organisms Daphnia magna and Thamnocephalus platyurus. Based on the test results the ecotoxicological values LC50, EC50 and IC50 for the tested substances were evaluated and their ecotoxicity was compared. Lilial showed the highest ecotoxicity. Value of 24h EC50 for organism Daphnia magna was 2.13 mg/l and value of 24h LC50 for the organism Thamnocephalus platyurus was 10.86 mg/l.
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Müller, Severin. "Risk evaluation of bioactive compounds in humans : I Synthetic musk fragrances : II Alkylphenols /". Zürich, 1997. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12175.
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Vallecillos, Marsal Laura. "Applicability of microextraction techniques for the etermination of synthetic musk fragrances in environmental samples". Doctoral thesis, Universitat Rovira i Virgili, 2015. http://hdl.handle.net/10803/334685.
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Aquesta Tesi doctoral se centra en el desenvolupament de mètodes analítics alternatius, més respectuosos amb el medi ambient, per la determinació de fragàncies sintètiques en mostres mediambientals tals com aigües residuals, llots de depuradora i organismes marins. Les fragàncies sintètiques incloses en aquesta Tesi formen part de les famílies de mescs policíclics, nítrics i macrocíclis.
En aquesta Tesi, tècniques de microextracció convencionals com ara la microextracció en fase sòlida (SPME), la microextracció mitjançant barres magnètiques (SBSE) i l’extracció en fase sòlida (SPE) on-line així com tècniques de microextracció més recents com la microextracció mitjançant gota penjant (SDME), la microextracció amb sorbents empaquetats (MEPS) i la microextracció amb agulles empaquetades (NME) s’han fet servir per a la preconcentració de les fragàncies subjectes a estudi. Sempre en combinació amb la cromatografia de gasos acoblada a l’espectrometria de masses (GC-MS) o a la espectrometria de masses en tàndem (MS/MS) com a tècniques de separació i detecció, respectivament. L’aplicació d’aquestes tècniques ha resultat ser una eina de gran utilitat pel desenvolupament de metodologies amigables amb el medi ambient degut a la disminució del consum de solvents orgànics i del volum de mostra. A més a més, el risc de contaminació de la mostra es veu minimitzat per la possibilitat d’automatització de tot el procés d’extracció. Per altre banda, l’extracció mitjançant fluits pressuritzats (PLE) i una tècnica d’extracció de recent ús en el món de l’anàlisi mediambiental, quick, easy, cheap, effective, rugged and safe (QuEChERS), han estat estudiats per l’anàlisi de llots de depuradora i organismes marins.
L’avaluació de la biodegradació dels mescs policíclics més representatius mitjançant l’enzim laccase així com la posterior identificació dels productes de degradació també ha estat inclosa en aquesta Tesi.Esta Tesis doctoral se centra en el desarrollo de métodos analíticos alternativos, más respetuosos con el medio ambiente, para la determinación de fragancias sintéticas en muestras medioambientales tales como aguas residuales, lodos de depuradora y organismos marinos. Las fragancias sintéticas incluidas en esta Tesis pertenecen a las familias de almizcles policíclicos, nítricos y macrocíclicos. En esta Tesis, técnicas de microextracción convencionales como la microextracción en fase sólida (SPME), la extracción mediante barra magnética (SBSE) y la extracción en fase sólida (SPE) on-line así como técnicas de microextracción de reciente uso como la microextracción mediante gota colgante (SDME), la microextracción con sorbentes empaquetados (MEPS) y la microextracción mediante agujas empaquetadas (NME) se han usado para la preconcentración de las fragancias sujetas a estudio. Siempre en combinación con la cromatografía de gases acoplada a la espectrometría de masas (GC-MS) o a la espectrometría de masas en tándem (GC-MS/MS) como técnicas de separación y detección, respectivamente. La aplicación de estas técnicas ha resultado ser una herramienta de gran utilidad para el desarrollo de metodologías amigables con el medioambiente debido a la reducción en el consumo de disolventes orgánicos y el volumen de muestra. Además, el riesgo de contaminación de la muestra se minimiza mediante la posibilidad de automatización de todo el proceso de extracción. De igual modo, la extracción mediante fluidos presurizados (PLE) y una técnica de extracción de reciente uso en el mundo del análisis medioambiental, quick, easy, cheap, effective, rugged and safe (QuEChERS), fueron estudiados para el análisis de lodos de depuradora y organismos marinos. La evaluación de la biodegradación de los almizcles policíclicos más representativos mediante la enzima laccase así como la posterior identificación de los productos de degradación también fue incluida en esta Tesis.
This doctoral Thesis focuses on the development of environmentally friendly analytical methods to determine synthetic musk fragrances in environmental samples such as wastewater, sewage sludge and marine organisms. The fragrances included in this Thesis belong to polycyclic musk, nitro musk and macrocyclic musk families. In this Thesis, conventional microextraction techniques such as solid-phase microextraction (SPME), stir bar extraction (SBSE) and on-line solid-phase extraction (SPE) as well as novel microextraction techniques as single-drop microextraction (SDME), microextraction by packed sorbents (MEPS) and needle trap microextraction (NMME) were used for the preconcentration of the fragrances studied. Always in combination with gas chromatography coupled to mass spectrometry (GC-MS) or tandem mass spectrometry detection (GC-MS/MS) as separation and detection techniques, respectively. The applicability of these techniques was shown to be a powerful tool for the development of environmentally friendly methodologies due to the reduction of solvent consumption and sample volume. Furthermore, the risk of sample contamination is minimized since the whole procedure could be automatized. In addition, pressurized liquid extraction (PLE) and an emerging extraction technique in the field of environmental analysis, as quick, easy, cheap, effective, rugged and safe (QuEChERS), were explored for the analysis of sewage sludge and marine organisms. The evaluation of the biodegradation of the most representative polycyclic musk via a laccase mediator system and the subsequent identification of the degradation products generated was also included in this Thesis.
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Turan, Hatice. "Développement analytique pour l'analyse des isotopes stables spécifiques au composé (CSIA) appliquée aux contaminants organiques émergents : étude de cas du galaxolide". Electronic Thesis or Diss., Pau, 2024. http://www.theses.fr/2024PAUU3019.
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Les Contaminants d'Intérêt Émergent (CECs) représentent une vaste gamme de produits chimiques synthétiques non réglementés qui constituent des menaces potentielles pour les écosystèmes aquatiques et la santé humaine. Parmi ces CECs, le Galaxolide (HHCB), un ingrédient de musc synthétique largement utilisé dans de nombreux produits commerciaux, a été classé comme produit chimique à Grand Volume de Production (HPV) par l'Organisation de Coopération et de Développement Économiques (OCDE) depuis 2004. HHCB est principalement détecté dans les eaux d'effluent et rejeté dans les milieux aquatiques sans être totalement éliminé. Malheureusement, seule la mesure des concentrations de HHCB dans les échantillons environnementaux ne fournit pas d'informations sur son l'origine ou et son devenir dans les milieux aquatiques. L'analyse Isotopique de Composés Spécifiques (CSIA) a émergé comme un outil pour identifier le sort des CECs en traçant leurs signatures isotopiques individuelles, sans nécessiter de données sur leur concentration. Cependant, l'application du CSIA dans les produits de soins personnels contenant du HHCB reste limitée. Développer une méthode CSIA est essentiel pour comprendre pleinement l'histoire de vie du HHCB. Dans ce contexte, nous avons étudié la biodégradation et la photodégradation, processus clés pouvant dégrader le HHCB dans les milieux aquatiques. L'objectif spécifique était d'évaluer la CSIA pour discriminer le sort, la source ou l'origine du HHCB. Deux bactéries, Priestia sp. 35 ODPABA G14 et Rhodococcus sp. 23 AHTN G14, précédemment isolées de sédiments sous-marins, ont été testées pour leur résistance ainsi que leur potentiel à dégrader non seulement le HHCB mais aussi d'autres CECs incluant les muscs synthétiques, les filtres UV, les produits pharmaceutiques et les pesticides. Priestia sp. et Rhodococcus sp. ont montré un potentiel de biodégradation élevé, en particulier pour les composés hydrophobes. Bien que cela ne s'applique pas à tous les CECs, les résultats indiquent une corrélation positive entre la résistance bactérienne marine aux CECs et leur potentiel de biodégradation significatif. De plus, nous avons étudié la cinétique de la photodégradation directe et indirecte pour identifier le rôle des espèces réactives responsables de la dégradation du HHCB sous la lumière du soleil et UVC, ainsi que pour déterminer ses produits de transformation. Les conditions environnementales représentatives avec de l'acide humique, du carbonate (CO3-2) et du nitrate (NO3-) ont été testées dans de l'eau ultrapure. Pour évaluer l'effet du prétraitement et du post-traitement, des eaux fluviales et d'effluents ont été utilisées. Ces expériences ont révélé l'efficacité de la photolyse directe dans la dégradation du HHCB sous les deux conditions de lumière. 3DOM*, •OH, CO3•- et 1O2 sont les principales espèces réactives qui peuvent contribuer à la dégradation du HHCB via la photolyse indirecte à des taux différents selon la matrice et la lumière. La Lactone HHCB, un produit de transformation bien connu, et deux autres substances dont les structures ont été proposées ont été détectées. Enfin, le potentiel de la CSIA à identifier les processus de photodégradation (sous UVC) et de biodégradation (par Priestia sp.) et à tracer la source et l'origine du HHCB dans les produits de soins personnels a été évalué. Les expériences par lots n'ont révélé aucun fractionnement isotopique significative pendant la photodégradation et la biodégradation. Bien qu'il y ait une grande variation des concentrations de HHCB dans les produits de soins personnels, atteignant des niveaux dépassant 15 g L-1 dans certains cas, les valeurs de δ13C seules étaient insuffisantes pour distinguer leurs sources ou origines. Par conséquent, ce travail contribue à une meilleure compréhension du sort du HHCB dans les milieux aquatiques et met en évidence le potentiel futur de la CSIA pour déterminer la source et l'origine des CECsThe Contaminants of Emerging Concern (CECs) represent a wide range of unregulated human-made chemicals that pose potential threats to both aquatic ecosystems and human health. Among these CECs, Galaxolide (HHCB), a widely used synthetic musk ingredient in many commercial products, has been listed as High Production Volume (HPV) chemical by the Organization for Economic Cooperation and Development (OECD) since 2004. HHCB is primarily detected in effluent waters and released into aquatic environments without complete removal. Unfortunately, the measurement of HHCB concentrations in environmental samples fails to provide insights into either the fate or the origin in aquatic ecosystems. Compound Specific Isotope Analysis (CSIA) has emerged as a tool for identifying the fate of CECs by tracing their individual isotopic signatures, without requiring data on their concentration. However, the application of CSIA in personal care products containing HHCB remains limited. Developing a CSIA method is essential for fully understanding the life story of HHCB. In this context, we studied biodegradation and photodegradation, key processes that can degrade HHCB in aquatic environments. The specific objective was to evaluate CSIA to discriminate the fate, source, or origin of HHCB. Two bacteria Priestia sp. 35 ODPABA G14 and Rhodococcus sp. 23 AHTN G14, previously isolated from submarine sediments, were tested for their resistance as well as their potential to degrade not only for HHCB but also for other CECs including synthetic musks, UV filters, pharmaceuticals and pesticides. Priestia sp. and Rhodococcus sp. showed high biodegradation potential, especially for hydrophobic compounds. Although this may not apply to all CECs, the results indicate a positive correlation between marine bacterial resistance to CECs and their significant biodegradation potential. Additionally, we investigated the kinetics of direct and indirect photodegradation to identify the role of reactive species responsible for HHCB degradation under sunlight and UVC light, as well as to determine its transformation products. Representative environmental conditions in the presence of humic acid, carbonate (CO3-2), and nitrate (NO3-) were tested in ultrapure water. To evaluate the effect of pre-treatment and post-treatment effect, riverine and effluent waters were used. These experiments revealed the effectiveness of direct photolysis in degrading HHCB under both light conditions. 3DOM*,•OH, CO3•-, and 1O2 are the main reactive species that can contribute to HHCB degradation via indirect photolysis at different rate depending on the matrix and light. HHCB Lactone, a well-known transformation product, and two other substances with proposed structures were detected. Finally, the potential of CSIA to identify photodegradation (under UVC) and biodegradation (by Priestia sp.) processes and to trace the source and origin of HHCB in personal care products was evaluated. Batch experiments revealed no significant isotopic fractionation during both photodegradation and biodegradation. Although there is wide variation in the HHCB concentrations in personal care products, reaching levels exceeding 15 g L-1 in some cases, δ13C values alone were insufficient to distinguish their sources or origins. Consequently, this work contributes to a better understanding of the fate of HHCB in aquatic environments and highlights the future potential of CSIA for determining the source and origin of CECs
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Švarcová, Lucie. "Chirální analýza syntetických vonných látek ve vodním ekosystému". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217084.
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Diploma thesis summarizes available information about chiral analysis of synthetic musk compounds in the aquatic environment. In the theoretical part of the thesis chirality and importance of chiral analysis by means of examples of different environmental pollutants is documented. Further consideration is aimed on musk compounds, their classification, characteristics and their fate in the environment, especially in the aquatic environment. After that methods for chiral analysis of synthetic musk compounds are reviewed. The aim of the experimental part of this diploma thesis was to carry out the determination of thirteen representatives of musk compounds (2-cyclohexylethanol, allylcyklohexylpropionate, Arocet, Aroflorone, Citronellol, Fresco Menthe, Galaxolide, hexyl cinnamic aldehyde, HSA, isoamylsalicylate, isobornylacetate, Lilial and Linalool), out of which some compounds are chiral and some are achiral. For the analysis samples of wastewater from the wastewater treatment plant Brno - Modřice were taken. Target compounds were isolated by solid phase microextraction (SPME) and were subsequently analyzed by gas chromatography with flame ionization and mass spectrometric detection. On the basis of data evaluation the removal efficiency forgiven musk compounds in the wastewater treatment plant was assessed.
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Musa, Musiliyu Ayodele. "Applications of the Baylis-Hillman reaction in the synthesis of coumarin derivatives". Thesis, Rhodes University, 2003. http://eprints.ru.ac.za/2319/1/MUSA-PhD-TR03-74.pdf.
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The reaction of specially prepared salicylaldehyde benzyl ethers with the activated alkenes, methyl acrylate or acrylonitrile, in the presence of the catalyst, DABCO, has
afforded Baylis-Hillman products, which have been subjected to conjugate addition with either piperidine or benzylamine. Hydrogenolysis of these conjugate addition products in the presence of a palladium-on-carbon catalyst has been shown to afford the corresponding 3-substituted coumarins, while treatment of O-benzylated Baylis-Hillman adducts with HCl or HI afforded the corresponding 3-(halomethyl)coumarins directly, in up to 94%. The 3-(halomethyl)coumarins have also been obtained in excellent yields (up to 98%) and even more conveniently, by treating the unprotected Baylis-Hillman products with HCl in a mixture of AcOH and Ac2O, obtained from tert-butyl acrylate and various salicylaldehydes. The generality of an established route to the synthesis of coumarins via an intramolecular Baylis-Hillman reaction, involving the use of salicylaldehyde acrylate esters in the presence of DABCO, has also been demonstrated.
Reactions between the 3-(halomethyl)coumarins and various nitrogen and carbon nucleophiles have been shown to proceed with a high degree of regioselectivity at the exocyclic allylic centre to afford 3-substituted coumarin products. The electronimpact mass spectra of selected coumarin derivatives have been investigated using high-resolution and B/E linked scan data. Fragmentation pathways have been
proposed and fragmentation modes associated with different coumarin-containing analogues have been compared.
A series of coumarin-containing analogues of ritonavir (a clinically useful HIV-1 protease inhibitor) have been prepared and characterized. The synthetic approach has
involved the coupling of coumarin derivatives with a hydroxyethylene dipeptide isostere to afford ritonavir analogues containing coumarin termini. An interactive docking procedure has been used to explore the docking of ritonavir and a coumarincontaining analogue into the enzyme active site.
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Schwarz, Diemo. "Spectral envelopes in sound analysis and synthesis". [S.l.] : Universität Stuttgart , Fakultät Informatik, 1998. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB7084238.
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Bürger, Michael [Verfasser]. "On the Analysis and Synthesis of Local Sound Fields for Personal Audio / Michael Bürger". München : Verlag Dr. Hut, 2019. http://d-nb.info/1202169015/34.
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Pfeifle, Florian Verfasser] y Rolf [Akademischer Betreuer] [Bader. "Physical model real-time auralisation of musical instruments : analysis and synthesis / Florian Pfeifle. Betreuer: Rolf Bader". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1108769462/34.
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Alexandraki, Chrisoula Verfasser] y Rolf [Akademischer Betreuer] [Bader. "Real-time Machine Listening and Segmental Re-synthesis for Networked Music Performance / Chrisoula Alexandraki. Betreuer: Rolf Bader". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2014. http://d-nb.info/1064077587/34.
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Luo, Li [Verfasser] y Peter [Akademischer Betreuer] Jung. "Implementation and Optimization of the Synthesis of Musical Instrument Tones using Frequency Modulation / Li Luo ; Betreuer: Peter Jung". Duisburg, 2017. http://d-nb.info/1136270248/34.
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Coler, Henrik von [Verfasser], Stefan [Gutachter] Weinzierl, Miller [Gutachter] Puckette y Diemo [Gutachter] Schwarz. "A system for expressive spectro-spatial sound synthesis / Henrik von Coler ; Gutachter: Stefan Weinzierl, Miller Puckette, Diemo Schwarz". Berlin : Technische Universität Berlin, 2021. http://d-nb.info/1230468382/34.
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Disch, Sascha [Verfasser]. "Modulation vocoder for analysis, processing and synthesis of audio signals with application to frequency selective pitch transposition / Sascha Disch". Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2011. http://d-nb.info/1014323789/34.
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Abeßer, Jakob [Verfasser], Gerald [Akademischer Betreuer] Schuller, Meinard [Gutachter] Müller y Anssi [Gutachter] Klapuri. "Automatic Transcription of Bass Guitar Tracks applied for Music Genre Classification and Sound Synthesis / Jakob Abeßer ; Gutachter: Meinard Müller, Anssi Klapuri ; Betreuer: Gerald Schuller". Ilmenau : TU Ilmenau, 2014. http://d-nb.info/1178180433/34.
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Abeßer, Jakob [Verfasser], Gerald [Akademischer Betreuer] Schuller, Meinard Gutachter] Müller y Anssi [Gutachter] [Klapuri. "Automatic Transcription of Bass Guitar Tracks applied for Music Genre Classification and Sound Synthesis / Jakob Abeßer ; Gutachter: Meinard Müller, Anssi Klapuri ; Betreuer: Gerald Schuller". Ilmenau : TU Ilmenau, 2014. http://d-nb.info/1178180433/34.
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Ramos, Sara Fernandes. "Emerging contaminants, from waste to taste? - Ultraviolet-Filters and Synthetic Musk Compounds as case study". Doctoral thesis, 2020. https://hdl.handle.net/10216/127202.
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Ramos, Sara Fernandes. "Emerging contaminants, from waste to taste? - Ultraviolet-Filters and Synthetic Musk Compounds as case study". Tese, 2020. https://hdl.handle.net/10216/127202.
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Wang, Yu-Chen y 王妤甄. "Determination of Synthetic Polycyclic Musk in Aqueous Samples by Microwave-Assisted HS-SPME & GC/MS". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/75039727805755011937.
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碩士國立中央大學
化學研究所
97
Synthetic musk fragrances are a group of chemicals used widely in detergents, perfumes, shampoos, and many other personal care products. According to their physical and chemical properties, they are in common with many hydrophobic and semivolatile organic pollutants that are known to biomagnify through the food chain. The occurrence of synthetic polycyclic musks, a group of the most concern synthetic musk fragrances currently, has been reported in air, freshwater, seawater and sediment suggesting that they are widespread contaminants in the environment. Because of their highly lipophilic properties, polycyclic musks have been also found in aquatic biota, such as mussels and fish, and even in human adipose tissue and breast milk. These compounds have been shown to demonstrate estrogenic activities, even higher concentrations of synthetic polycyclic musks in women''s bloods have been correlated to higher rate of miscarriage. In this study, the sample pretreatment technique of microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) has been developed and studied for the extraction of six commonly used synthetic polycyclic musks (i.e., Galaxolide (HHCB), Tonalide (AHTN), Celestolide (ADBI), Traseolide (ATII), Cashmeran (DPMI) and Phantolide (AHMI)) in aqueous samples prior to gas chromatography-mass spectrometry (GC-MS) analysis. The effects of various extraction parameters (i.e., extraction time, microwave power and addition of salt) for the quantitative extraction of these polycyclic musks by MA-HS-SPME were systematically investigated and optimized. The analytes can be extracted by 65 ?m PDMS/DVB fiber under 180 W microwave power for 4 min, 20 mL water sample added 4 g NaCl was put in 40 mL vial with headspace 20 mL (the ratio of sample : headspace = 1:1, v/v). The limit of detection (LOD) ranged from 0.05 to 0.1 ng/L and the limit of quantification (LOQ) was less than 0.2 ng/L. Preliminary results show that HHCB and AHTN were two commonly detected polycyclic musks in real environmental samples, ranging from 1.2 to 37.3 ng/L via standard addition method with correlation coefficient (r2) above 0.981. The analytical procedure developed herein demonstrated that the MA-HS-SPME and GC-MS-SIM methods are reliable, sensitive and offer a convenient analytical technique for trace determination of polycyclic musks in various water samples.
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Arruda, Vitória Sousa. "Impact of the presence of synthetic musk compounds in the behaviour of biofilms in drinking water distribution systems". Master's thesis, 2021. https://hdl.handle.net/10216/135346.
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Arruda, Vitória Sousa. "Impact of the presence of synthetic musk compounds in the behaviour of biofilms in drinking water distribution systems". Dissertação, 2021. https://hdl.handle.net/10216/135346.
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Alves, Alice Maria de Araújo. "Detection of synthetic musk fragrances in aqueous matrices by ultrasound-assisted dispersive liquid-liquid microextraction followed by GC-MS". Master's thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/89058.
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Alves, Alice Maria de Araújo. "Detection of synthetic musk fragrances in aqueous matrices by ultrasound-assisted dispersive liquid-liquid microextraction followed by GC-MS". Dissertação, 2014. https://repositorio-aberto.up.pt/handle/10216/89058.
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Cunha, Ana Carina de Carvalho. "Synthetic musks in personal care products : method development and exposure assessment". Master's thesis, 2012. http://hdl.handle.net/10216/68107.
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Cunha, Ana Carina de Carvalho. "Synthetic musks in personal care products : method development and exposure assessment". Dissertação, 2012. http://hdl.handle.net/10216/68107.
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Tseng, Wei-Ju y 曾薇如. "Determinations of Synthetic Musks in Personal Care Products by Solid-Phase Microextraction". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/43603240813327507319.
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碩士國立臺灣大學
環境衛生研究所
103
Synthetic musk is widely used as fragrances in many personal care products for enhancing scent and covering odor in recent years. Hence, the US Environmental Protection Agency (USEPA) classified polycyclic musk as one of the High Production Volume (HPV) chemicals. Synthetic musk is found to be related with several health concerns such as photo-allergic reactions and neurotoxicity. From in vivo and in vitro studies, there are evidences that some synthetic musks are considered as the potential endocrine disruptors. Concerning the possible heath effect and the fact that synthetic musk is commonly detected in the environment and human samples, the information for the distributions of synthetic musks in various personal care products should be acquired. Solid-phase microextraction (SPME) is an ideal tool by combining sampling, extraction, concentration and injection into a single process. However, to the best of our knowledge, studies are still limited regarding the analysis of synthetic musk in personal care products by SPME. As a result, SPME procedures need to be validated first before the determinations of synthetic musks in personal care products can be performed. 12 synthetic musk mixtures were analyzed by solid phase microextraction method (SPME) in multiple reaction monitoring (MRM) mode. The samples were first diluted by water before the extraction. The optimum extraction was performed at 70°C for 40 minutes with 300 rpm. The 65μm PDMS/DVB fiber was exposed to the headspace over the samples. A little carry-over effects was observed from the thermal desorption of the sample. The sensitivities of the method for different compounds were low enough to determine the concentrations from personal care products The linear range and method detection limits (MDL) of polycyclic musk compounds were 0.01 to 2 ng/ml, 0.002 ng/ml respectively and the linear range for nitro musk was 0.1 to 20 ng/ml, the MDL was 0.05 ng/ml. Good linearity and precision were presented and the recoveries ranged from 91%-135%. This study provided the first data of synthetic musks level in Taiwan, more than 100 products samples in Taiwan were determined for the concentrations of both polycyclic musk and nitro musk., it was found that the high occurrence percentage and high concentration in products samples especially for compounds HHCB (15,555μg/g), AHTN (13,398μg/g), DPMI (2,013μg/g) and MK (8,324μg/g). The high level of synthetic musks were mainly found in perfumer, body lotion and hair care products categories. Daily dermal exposure was estimated, based on the mean concentrations of musks, the daily exposure of total synthetic musks through application of personal care products was 22.54μg /kg/day. The results indicates that perfume and body lotion were major sources of human exposure, which occupied 96% for HHCB. Furthermore, compared to other exposure route, it strongly suggested that dermal absorption from personal care product was expected to be the main source of human exposure. For future work, further researches are acquired to obtain the data regarding the absorption rate, toxicity and concentration of synthetic musks in different environmental matric to assess health risk.
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HU, CHIH-YUN y 胡芷昀. "The Study of High Performance Liquid Chromatographic Analysis for Synthetic Musks in Cosmetics". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/8m65g7.
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碩士嘉南藥理大學
化粧品應用與管理系
104
Emerging Contaminants have attract much attention as environmental issues in recent years. The use of Synthetic Musks, one of the Emerging Contaminants is cosmetics has growing rapidly as well. Their presence in of concern due to the possible impact on ecology or human health. Therefore Non-regulated synthetic musk in perfumes personal care products or other cosmetics are focused on due to the possible on going policy initiatives of expectant legislation. The major goal of this study is to establish an analytical method to measure the content of synthetic musks in different matrix of cosmetics.Nitro Aromatic musk, Musk Ketone, Musk Ambrette and Polycyclic Musk, Galaxolide® and Tonalide®,were selected for this study. These compounds are separated and determined by gas and liquid chromatographic method.The optimum chromatographic conditions for easily determining of the Musk content in cosmetic samples was obtained as liquid chromatographic analysis using Agilent HC-C18 column and gradient elution by acetonitrile aqueous solution at 1mL/min and detected at 214nm. The synthetic musks under study can be completely separated within 30 minutes. The results show that the correlation coefficient of calibration curve of all standards are above 0.9995 and the standard errors of intraday analysis are below 1.50 % which gives good accuracy and precision. The application of this methods to self-prepared and commercial sample analysis also show good accuracy and precision with relative standard derivation below 5 % and spike recovery within 100±10 %. The proposed methods shows promising results for simple sample preparation and easy operation of the synthetic musk analysis. It should be appropriate to apply this method for the determination or policy initiatives of synthetic musk in cosmetics.
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Wu, Shin-Fang y 吳欣芳. "Fast Determination of Synthetic Polycyclic Musks in Solid Samples by Solvent Free Techniques". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/10781221893366054387.
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碩士國立中央大學
化學研究所
98
Fragrances have been used increase attractiveness of persons since ancienttimes. Musk is one of the most important and often used fragrances in perfumery. Synthetic polycyclic musks are inexpensive substitutes for natural musks. Synthetic polycyclic musk compounds enter environment principally through effluents of wastewater treatment plants and waste sludge, and the major source of environmental pollution of synthetic musks is from sewage. In this study, one-step in situ microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis is presented as a fast and solvent-free technique to determine synthetic polycyclic musks in sewage sludge, sediment and oyster samples. The dewatered solid sample mixed with 20-mL deionized water was efficiently extracted by a polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber placed in the headspace when the extraction slurry was microwave irradiated at 80 W for 5 min. The limits of detection (LODs) ranged from 0.04 to 0.1 ng/g, and the limits of quantification (LOQs) ranged from 0.1 to 0.3 ng/g (fresh weight). A preliminary analysis of those samples revealed that HHCB and AHTN were the two most commonly detected synthetic polycyclic musks; using a standard addition method, their total concentrations were determined to rangefrom 0.3 to 10.9 ng/g (fresh weight) with relative standard deviation (RSD)ranging from 4% to 10%. The analytical procedure developed demonstrated that the MA-HS-SPME and GC-MS-SIM methods are reliable, sensitive and offer a convenient analytical technique for trace determination of polycyclic musks in various solid samples in environment.
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Magalhães, Inês Isabel da Silva. "Detection of synthetic musks in beach sands by QuEChERS and GC-MS analysis". Master's thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/89484.
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Magalhães, Inês Isabel da Silva. "Detection of synthetic musks in beach sands by QuEChERS and GC-MS analysis". Dissertação, 2014. https://repositorio-aberto.up.pt/handle/10216/89484.
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Soares, Rodrigo Manuel Custódio. "Detection of synthetic musks and UV-filters in Carpobrotus edulis by QuEChERS/GC-MS". Master's thesis, 2016. https://hdl.handle.net/10216/88850.
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Soares, Rodrigo Manuel Custódio. "Detection of synthetic musks and UV-filters in Carpobrotus edulis by QuEChERS/GC-MS". Dissertação, 2016. https://hdl.handle.net/10216/88850.
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Wu, Ming-wei y 吳銘緯. "Analysis of synthetic musks and occurence of alkylphenols in biota samples with green chemistry techniques". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/05841632076205075869.
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碩士國立中央大學
化學研究所
100
The use of musk flavor has a long history dating back to ancient times. Until the end of the nineteenth century the popular fragrance was obtained from natural sources. Nowadays synthetic compounds are almost exclusively used. They can be divided into four major classes: aromatic nitro musks, polycyclic musks, macrocyclic musks, and alicycloc musks. Due to their flavor odor and lower price, synthetic musks use to be added to personal care products, and release by the waste sludge and sewage. Musks also can easily accumulate in water, sludge, and biota, therefore a simple and effective method is required. The first part of this study, one-step in situ microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) coupled with gas chromato- graphy-mass spectrometry (GC-MS) analysis was presented as a fast and eco-friendly technique to determine synthetic musks in fish samples. The fish sample mixed with 5 mL MeOH and 13 ml deionized water was efficiently extracted by a polymehtylsiloxane- divinylbenzene (PDMS/DVB) fiber place in the headspace when extraction was microwave irradiated at 80 W for 5 min. The limits of detection (LODs) ranged from 0.08 ng/g to 0.5 ng/g and the limits of quantification (LOQs) ranged from 0.3 ng/g to 2 ng/g. A preliminary analysis of fish samples revealed that all sample can be detected the synthetic musks, using a standard addition method, musks concentration were determined to range from 1.0 to 14.0 ng/g with relative standard deviation (RSD) ranging from 0.4 % to 9.8 %. The results show that this MA-HS-SPME and GC-SIM-MS are reliable, sensitive, and stable analytical technique for a trace determination of synthetic musks in fish. 4-tert-octylphenol (4-t-OP) and 4-nonylphenol isomers (4-NPs) are two persistent degradation products form widely used nonionic surfactants alkylphenol polyethoxylates (APEOs). They have been demonstrated to exhibit the ability to mimic natural hormones. The second part of this study is analysis and monitors the hydrophobic alkylphenol compounds in snail in Taiwan. In this study, one-step steam-distillation extraction followed by a gas chromatography-mass spectrometry is presented as a simple technique to determine alkylphenols in snail samples. The snail sample mixed with 100 ml deionized water into 250 mL round bottle, and connected with steam distillation tube which contained 4 mL hexane, then extraction for one hour. The recovery for each samples range from 80.3 % to 114.9 % with RSD ranged from 2.4% to 12.7%. The 4-NPs concentrations ranged from 23 ng/g to 3370 ng/g in 4 different species (Natica lineata, NL, Neverita didyma, Nd, Thais clavigera, TC, Babylonia areolata, BA), but 4-t-OP was not detected in snail samples. The results showed that the concentration of 4-NPs in snails were significant different among sampling locations, species, and years.
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Paul, Vimla. "Synthesis and characterization of a biocomposite derived from banana plants (Musa cavendish)". Thesis, 2015. http://hdl.handle.net/10321/1286.
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Submitted in fulfillment of the requirements of the degree of Doctor of Philosophy in Chemistry, Durban University of Technology. Durban, South Africa, 2015.Over decades synthetic composites have become an indispensable part of our lives with their various applications such as packaging, sporting equipment, agriculture, consumer products, medical applications, building materials, automotive industry, and aerospace materials among others. Although these polymers have the desired properties for the above applications, they are invariably costly. Furthermore, they cannot be easily disposed of at the end of their useful lives and simply pile up and cause significant damage to the environment. However, the dwindling supply of fossil fuel, increased oil prices, together with the growing public concern of greenhouse gas emissions and global warming, has forced scientists to search for new development of sustainable materials from renewable resources. Hence in recent years, there is an increased interest in biocomposite manufacturing with natural resources as environmental issues are addressed. The research work presented in this dissertation is to the best of the author’s knowledge a world-first overall investigation pertaining to the concept of synthesizing a banana sap based bio-resin (BSM) reinforced with banana fibres. In this work the chemical composition of banana sap was determined to investigate the chemical reactions taking place in the resin formulation. BSM was synthesized, characterized and proposed as a potential bio-resin to be used in the biocomposite manufacture for non-functional motor vehicle components. BSM, a hybrid bio-resin was synthesized with equimolar quantities of maleic anhydride and propylene glycol and 50% banana sap. A control resin without the banana sap was also synthesized for comparison purposes. It was proposed that the presence of sugars, esters and pthalates from the sap, determined by HPLC and GC-MS, contributed to the cross-linking of the polymer chain. The acid value and viscosity of BSM were determined and found to be within specification of an industry resin. The molecular weights of the BSM and control resins were 2179 and 2114 units respectively. These were within the required molecular weight of unsaturated polyester resins. The gel and cures times of the BSM were 60% lower than the control resin suggesting that the banana sap behaved as an accelerator for the curing process. The lower cure time meant that using the banana sap in the formulation was cost effective and time saving. The thermal properties of BSM showed improved degradation temperatures and degree of crystallinity compared to the control resin. A parametric study showed that increasing banana sap concentration in the resin formulation led to increased tensile and flexural properties with 50% being the optimum amount of sap to be added to the formulation. The synthesized bio-resin and control resin were applied to biocomposites and characterized in terms of physical, thermal, mechanical, morphological, chemical and biodegradable properties. Mechanical tests indicated a 15 % increase in tensile strength, 12 % improvement in tensile modulus and a 25 % improvement in the flexural modulus, when compared to structures produced without banana sap. Natural fibres present the challenge of poor adhesion to the matrix. Chemical treatment of the banana fibre was done to improve on the compatibility of resin to fibre. Fibre pull-out showed that treated fibres had a better bond than the untreated fibre. Parametric studies were also done to evaluate the effect of fortifying the BSM resin with nanoclay. A 5% clay loading resulted in a 24% increase in tensile strength and 28% increase in flexural properties. Finally biodegradation studies of the BSM bio-resin, BSM biocomposite, control resin and control composite were investigated and compared to a positive reference, cellulose. Results showed that over a period of 55 days the BSM biocomposite showed 17.6% biodegradation compared to 8% with the control composite. No difference in biodegradation between the BSM bio-resin and the control resin was recorded. BSM biocomposite was proposed as a potential replacement to synthetic composites that contribute to the environmental landfill problems. The main contribution of this research is the use of the reinforcement and matrix from the same natural source. An enriched understanding of the synthesis, characterization and performance of the banana sap based bio-resin and biocomposite for the use of non-functional motor vehicle components is the key outcome of this investigation.
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Fernandes, Ana Sofia Moreira Seabra. "Uptake of synthetic musks and volatile methylsiloxanes by pea crops grown in sewage sludge-amended soils". Master's thesis, 2021. https://hdl.handle.net/10216/137269.
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Hsu, Chung-Han y 許中涵. "Determination of Indoor Airborne Synthetic Musks by Dynamic Air Sampling with Solid-Phase Microextraction under Nonequilibrium Situation". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/68318701551454156061.
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碩士國立臺灣大學
環境衛生研究所
103
Synthetic musks have a widespread use and can be found in many personal-care products such as detergents, body wash, shampoo, perfume and cosmetics. Synthetic musks belong to emerging chemicals that are persistent, bio-accumulative and toxic, while their appearances in different environmental matrix can be discovered easily, including indoor air. Nevertheless, methods used to sample synthetic musks require a long sampling time or extensive work in the sample preparation process. Therefore, a method which is rapid, cost-effective and sensitive enough for the determination would be of great benefits. The aim of this research was then to develop a dynamic sampling method with aforementioned advantages based on solid phase microextraciton (SPME). Synthetic musks can be divided into two major classes, including nitro musks and polycyclic musk. Among them, Galaxolide (HHCB) and Tonalide(AHTN) was selected in this study since it was most commonly seen in the environment. The mixtures of HHCB were hence prepared and injected into the designed dynamic sampling system by a syringe pump. HHCB was sampled in the exposure chamber with different fibers under a fixed air velocity for different combinations of sampling time and concentrations. After exposures, the SPME fibers were inserted into the injection port of GC/MS/MS for thermal desorption and further analysis. The SPME procedure coupled with GC/MS analysis for the determinations of airborne synthetic musks was established in this study. It was observed that PDMS/DVB SPME fiber provided the best extraction efficiency with highest sample stability. The desorption efficiency was found to be 100% when the time for thermal desorption were 10 minutes which means no carry-over effect was observed. The theoretical sampling rate was estimated to be 0.20 cm3 sce-1. The linear range of the detection for HHCB was 1 ng mL-1 to 5 μg mL-1, and the method detection limit (MDL) was 0.10 ng mL-1. The experimental sampling constant and the effects of different environmental factors on the samplers were also validated. The designed method demonstrated the potential of using SPME fiber for synthetic musks determination, while advantages over conventional methods, such as solve-free and time-saving, were reached. It provided a simple and sensitive method to monitor the quality of indoor air in the future.
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Yang, Ching-ya y 楊清雅. "Ultrasound-assisted dispersive liquid-liquid microextraction for the rapid determination of synthetic polycyclic musks in aqueous samples". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/29755130701131347181.
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碩士國立中央大學
化學研究所
99
Currently, a group of widely used synthetic musk fragrances, synthetic polycyclic musks have been detected in air, freshwater, seawater and sediment samples. Because of their highly lipophilic properties, polycyclic musks have been also found in aquatic biota, such as mussels and fish, and even in human adipose tissue and breast milk. These compounds have demonstrated estrogenic activity, even higher concentrations of synthetic polycyclic musks in women''s bloods have been correlated to higher rate of miscarriage. In this study, a simple and solvent-less procedure was developed for the determination of six commonly found synthetic polycyclic musks in aqueous samples using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled gas chromatography-mass spectrometry (GC-MS). The parameters affecting the extraction efficiency of analytes from water samples were systematically investigated and the conditions optimized. The best extraction conditions involved the rapid injection of a mixture of 1.0 mL of isopropyl alcohol (as a dispersant) and 10 μL of carbon tetrachloride (as an extractant) into 10 mL of water containing 0.5 g of sodium chloride in a conical bottom glass tube. After ultrasonication for 1.0 min and centrifugation at 5000 rpm (10 min), the sedimented phase 1.0 μL was directly injected into the GC-MS system. The limits of quantitation (LOQs) were less than 0.5 ng/L. The precision for these analytes, as indicated by relative standard deviations (RSDs), were less than 13% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 62 and 104%. Using a standard addition method, their total concentrations were determined to be in the range from 8.3 to 63.9 ng/L in various environmental samples. The developed technique appears to be a good alternative extraction method for the determination of organic compounds in environmental water samples in that it is a simple, low cost, effective, and eco-friendly analytical method.
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Jiang, Zhao-Huan y 蔣昭歡. "Synthesis of Musk-T and Coumarin Absorbents by Molecular Imprinting Technique and Its Application on Sample Pretreatment Based on Magnetic Modification". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/68532060780553905658.
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碩士國立清華大學
奈米工程與微系統研究所
102
Artificial fragrances widely used in cosmetics, perfumes, detergents and other daily necessities are good alternatives to expensive natural flavors. Consequently, domestic sewage containing significant amount of artificial fragrances is discharged into the aquatic environment. Artificial fragrances are usually non-biodegradable, and results in bioaccumulation, disturbing the biological chain. Musk is very popular since ancient times. Deer musk is expensive and rare, therefore synthetic musk has gained more popularity. Musk-T, one of the synthetic musk, is used in my research. Another chemical is coumarin, which is also widely used as a fragrance in our daily life. But it is reported by the Health and Consumers Department of the European Union that coumarin is an allergen. In my research, MIPs for Musk-T and coumarin are successfully prepared, where MAA is used as the functional monomer, EGDMA as the cross-linker, and the polymerization reaction is initiated by AIBN. The average size of MIPs for Musk-T is 400-500 nm, and for the concentration of 0.05mM-1mM, the adsorption capacity is in between 1.88mg/g and 13.80mg/g. The highest imprinting factor is 4.1, and the lowest is 2.4. The size of MIPs for coumarin is 300-400 nm, the adsorption capacity is between 0.39-2.89 mg/g during the sample concentration of 0.02-0.5 mM. The imprinting factor is between 2.7 and 10.1, and has a good selectivity. The data is also analyzed by Scatchard Equation. Results show that there are two kinds of adsorption on the surface of both MIPs, specific binding and nonspecific binding. At last, the MIPs is modified by Fe3O4 using the EDC/NHS system, which makes the MIPs more convenient when it is used in the pretreatment process.
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Baalman, Marije Alberdina Johanna [Verfasser]. "On wave field synthesis and electro acoustic music, with a particular focus on the reproduction of arbitrarily shaped sound sources / vorgelegt von Marije Alberdina Johanna Baalman". 2008. http://d-nb.info/989646890/34.
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