Academic literature on the topic 'Volatif'
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Journal articles on the topic "Volatif"
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Asmuki, Asmuki. "UPAYA GURU PAI DALAM MEMBENTUK KARAKTER RELIGIUS MELALUI KEGIATAN KEAGAMAAN DI SMP MUHAMMADIYAH KARANGASEM BALI." Al-Insyiroh: Jurnal Studi Keislaman 2, no. 2 (October 12, 2018): 84–100. http://dx.doi.org/10.35309/alinsyiroh.v2i2.3323.
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Bangsa yang memiliki karakter yang kuat akan menjadikan dirinya sebagai bangsa yang bermartabat.tetapi kondisi bangsa ini yang semakin menunjukkan perilaku anti budaya dan anti karakter dan mengalami krisis moral seperti praktik korupsi, kolusi, dan nepotisme yang semakin marak pada lembaga pemerintahan Fenomena di atas jelas mendapatkan kritikan terutama dalam dunia pendidikan, karena dunia pendidikan kita saat ini dinilai lebih memperhatikan aspek kognitif semata dari pertumbuhan kesadaran nilai-nilai (agama) dan mengabaikan pembinaan aspek afektif dan konatif volatif, yakni kemauan dan tekad untuk mengamalkan nilai-nilai ajaran agama. Akibatnya terjadi kesenjangan antara pengetahuan dan pengalaman, antara gnosis dan praxis dalam kehidupan nilai agama. Atau dalam praktik pendidikan agama berubah menjadi pengajaran agama, sehingga tidak mampu membentuk pribadi-pribadi bermoral, padahal inti dari pendidikan agama adalah pendidikan moral. Kalau kita simak pendidikan atau mendidik tidak hanya sebatas mentransfer ilmu saja, namun lebih jauh pengertian itu yang lebih utama adalah dapat mengubah dalam tataran etika maupun estetika dalam kehidupan sehari-hari. Dalam riset kali ini akan dikaji pembentukan karakter religious disebuah sekolah umum yang berafisiliasi organisasi keagamaan di Karang Asem Bali
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Apriyanto, Donni Kis, and Mitrayana Mitrayana. "SERAPAN SENYAWA ORGANIK VOLATIL SEBAGAI BIOMARKER PENYAKIT KANKER PARU: SUATU MINI REVIEW." Biomedika 12, no. 2 (August 30, 2020): 58–64. http://dx.doi.org/10.23917/biomedika.v12i2.10114.
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ABSTRAKUlasan ini merupakan hasil studi literatur yang memberikan tinjauan umum serapan senyawa-senyawa organik volatil yang dianggap sebagai biomarker kanker paru. Senyawa-senyawa ini dapat menyerap pada panjang gelombang tertentu. Senyawa-senyawa organik volatil yang teridentifikasi didaftar dan dijabarkan panjang gelombang yang dapat mereka serap. Studi literatur ini menyajikan kelompok senyawa-senyawa organik volatil dapat menyerap pada rentang panjang gelombang inframerah. Hasil ulasan ini mungkin dapat bermanfaat untuk pengembangan skrinning kanker paru dengan menggunakan alat spektroskopi fotoakustik yang menggunakan sumber laser pada rentang panjang gelombang inframerah atau ultraviolet dengan memanfaatkan serapan panjang gelombang oleh senyawa-senyawa tertentu.Keyword: Biomarker Kanker Paru,Senyawa Organik Volatil, Spektroskopi ABSTRACTThis review is the result of a literature study that provides a general collection of volatile organic compounds (VOC) which are considered as markers for lung cancer. These compounds can absorb certain long waves. The volatile organic compounds identified are listed and described in wavelengths that they can absorb. Literature studies that produce volatile organic compounds in the analysis wavelength range. The results of this review may be useful for the development of lung cancer screening by photoacoustic spectroscopic devices that use laser sources in the range of infrared or ultraviolet wavelengths by utilizing wavelength absorb by certain compounds.Keyword: Lung Cancer Biomarker, Volatile Organic Compounds, Spectroscopy
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BARLINA, RINDENGAN. "Pengaruh Penyaringan Nira Terhadap Senyawa Volatil Gula Aren." Buletin Palma 16, no. 1 (September 9, 2016): 32. http://dx.doi.org/10.21082/bp.v16n1.2015.32-39.
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<p><span style="font-size: medium;">ABSTRAK </span></p><p>Nira aren merupakan bahan baku utama pengolahan gula merah. memanfaatan gula aren sangat beraneka ragam, terutama pada jenis-jenis makanan yang menghendaki rasa dan aroma khas dari gula aren, namun untuk produk tertentu tidak menghendaki adanya aroma dari gula aren. Penelitian ini dilakukan dengan tujuan mempelajari cara penyaringan nira aren dan melakukan identifikasi komponen volatil produk akhir gula aren. Penelitian dilaksanakan pada bulan Mei 2013 sampai Oktober 2013 di Tinoor Satu, Kecamatan Tomohon Utara, Laboratorium Balai Penelitian Tanaman Palma, Laboratorium Kimia dan Biokimia Jurusan Teknologi Hasil Pertanian, UGM-Yogyakarta, dan Laboratorium Flavor-Balai Besar Penelitian Tanaman Padi di Sukamandi. Nira yang sudah disiapkan disaring menggunakan tiga cara, yaitu: (a) penyaringan menggunakan kain saring, (b) penyaringan menggunakan kertas saring ditambah batu zeolit, dan (c) penyaringan menggunakan kertas saring ditambah batu zeolit dan hasil penyaringan ditambahkan kapur makan 0,25%. Selanjutnya nira diproses menjadi gula aren, dikemas menggunakan aluminium foil berlapis plastik kemudian di analisis kadar air, abu, lemak, protein, gula reduksi, sakarosa dan kalsium, sedangkan identifikasi senyawa volatil, menggunakan alat ekstraksi Likens-Nickerson dan Gas Chromatography Mass Spectrometry (GCMS). Hasil penelitian menunjukkan bahwa, pada umumnya nira yang mengalami penyaringan menyebabkan penurunan komponen makronutrien pada gula aren dan senyawa volatil. Penyaringan menggunakan kain saring menghasilkan gula aren dengan 24 jenis senyawa volatil konsentrasi 40,1314 ppm. Penyaringan dengan kertas saring tambah batu zeolit menghasilkan gula aren dengan 33 jenis senyawa volatil konsentrasi 0,1139 ppm. Penyaringan kertas saring tambah batu zeolite dan kapur makan jumlah senyawa volatil 28 jenis dengan konsentrasi 0,1292 ppm. Senyawa volatil yang dominan adalah pirazin, berturut-turut penyaringan menggunakan kain saring 31,5930 ppm. Penyaringan kertas saring tambah batu zeolit 0,0826 ppm dan penyaringan kertas saring tambah batu zeolit dan kapur makan 0,1075 ppm. Nira yang disaring menggunakan kertas saring dan ditambah batu zeolit yang menghasilkan senyawa volatil hanya 0,1139 ppm adalah yang baik karena senyawa non volatil seperti sakarosa meningkat sedangkan gula reduksi menurun dan warna gula masih khas gula aren.</p><p>Kata kunci: Nira aren, penyaringan, gula aren, volatil.</p><p> </p><span style="color: black; line-height: 115%; letter-spacing: -0.35pt; font-family: 'Arial Bold'; font-size: 14pt; mso-bidi-font-family: 'Arial Bold'; mso-font-width: 95%; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: IN; mso-fareast-language: IN; mso-bidi-language: AR-SA; mso-fareast-theme-font: minor-fareast;">Effect of Filtering Palm Sap to Volatile Compounds of Palm Sugar </span><p> </p><p><span style="font-size: medium;">ABSTRACT </span></p><p>Toddy of sugar palm is the main raw material for processing palm sugar. Utilization of palm sugar is various, especially in the types of foods that require a distinctive flavor and aroma of palm sugar, on the other hand some of products did not require any scent of palm sugar. This research had been done with the aim to study the palm sap method and to identify volatile compounds of palm sugar products. The experiment was conducted in May 2013 to October 2013 in Tinoor, Subdistrict North-Tomohon, Laboratory of Indonesian Palms Research Institute, Laboratory of Chemistry and Biochemistry Department of Agricultural Technology, Gadjah Mada University, Yogyakarta, and Laboratory Flavor of Rice Research in Sukamandi. Toddy that has been prepared is filtered using three methods which are : A ) filtration using filter cloth, B ) filtration using filter paper plus zeolite stone , and C ) filtering using filter paper plus zeolite stone and added 0.25 % limestone. Filtered toddy were processed to be palm sugar and then packed using plastic coated aluminium foil. Palm sugar then analyzed to contents of water, ash, fat, protein, reduction sugar, saccharose and calsium while identification of the volatile compounds, using a Likens-Nickerson extraction and Gas Chromatography Mass Spectrometry ( GCMS ). The results showed generally filtered toddy caused decreasing of macronutrients and volatile, compounds of palm sugar. Filtering using filter cloth produced palm sugar with 24 kinds of volatile compounds, concentration of 40.1314 ppm. Filtering paper added zeolite stone produced palm sugar with 33 kinds of volatile compounds concentration of 0.1139 ppm. Filtering paper added zeolite stone and limestone produced palm sugar with 28 kinds of volatile compounds concentration of 0.1292 ppm. The dominant volatile compound is pyrazine with concentrations respectively are filtration using filter cloth 31,5930 ppm, filter paper added zeolite stone 0.0826 ppm and filter paper added zeolite and limestone 0,1075 ppm. Toddy filtered using filter paper added zeolite store that produced volatile compounds only 0.1139 ppm was good. It means increasing non-volatile compounds such as sucrose and decreasing reduction sugar while the colour of sugar still typical of palm sugar.</p>Keywords: Toddy, filtering, palm sugar, volatile.
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Aznury, Martha, Tjandra Setiadi, and Adi Pancoro. "Pengaruh sumber karbon terhadap produksi bioplastik polihidroksialkanoat (PHA) dengan ralstonia eutropha." Jurnal Teknik Kimia Indonesia 9, no. 1 (October 2, 2018): 28. http://dx.doi.org/10.5614/jtki.2010.9.1.4.
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Bioplastic Polyhidroxyalknoate (PHA) is a polyester type bioplastic with physicochemical properties resemble to those of polypropilen from petroleum. PHA production was investigated to determine the effect of carbon source on the fermentation process by Ralstonia eutropha. Specifically, Ralstonia eutropha was cultivated in a batch bioreactor to show the dynamics of P(3HB-co-3HV) copolymer production from glucose or fructose as C source. In adition, the effect of volatile fatty acids addition, as stimulator to the copolymer production, was also studied. The operating conditions in a 7 L bioreactor were at temperature 30 oC and pH 7.0. The concentration of carbon source glucose or fructose was 40 g/L, and after 20 hour fermentation, volatile fatty acids were added. With volatile fatty acids addition, the resulting fructose fermentation had PHA content of 32.78%, in which the HV percentage was 11.78%. Meanwhile, the fermentation of glucose, stimulated by volatile fatty acids, gave PHA as much as 20.19% with HV percentage of 8.71%. Therefore,, the Ralstonia eutropha fermentation of fructose as the carbon source gave a higher yield than glucose. Keywords: Volatil Fatty Acid, Fructose, Glucose, PHA, P(3HB-co-3HV), Ralstonia eutropha AbstrakBioplastik polihidroksialkanoat (PHA) adalah bioplastik dari kelompok poliester dengan sifat fisikokimia mirip dengan plastik polipropilen dari minyak bumi. Penelitian ini bertujuan untuk mempelajari pengaruh sumber karbon terhadap poduksi PHA yang dilakukan dengan proses fermentasi menggunakan Ralstonia eutropha. Ralstonia eutropha dikultivasi dalam bioreaktor batch untuk mempelajari dinamika produksi kopolimer P(3HB-co-3HV) dari sumber karbon glukosa atau fruktosa, serta mempelajari pengaruh sumber stimulator asam lemak volatil. Kondisi operasional fermentasi menggunakan bioreaktor 7 L adalah pada temperatur 30 oC dan pH 7. Konsentrasi sumber karbon glukosa atau fruktosa yang digunakan adalah 40 gr/L, dan setelah 20 jam fermentasi ditambahkan asam lemak volatil yang berfungsi sebagai stimulator dalam produksi P(3HB-co-3HV). Panen sel Ralstonia eutropha dilakukan setelah 60 jam. Hasil penelitian menunjukkan fermentasi Ralstonia eutropha dengan substrat fruktosa dan asam lemak volatil sebagai stimulator mempunyai kandungan PHA sebesar 32,78%, dengan kadar HV 11,78%. Pada pemberian substrat glukosa dan asam lemak volatil menunjukkan kandungan PHA sebesar 20,19%, dengan kadar HV 8.71%. Jadi fermentasi Ralstonia eutropha dengan menggunakan substrat fruktosa memberikan yield yang lebih tinggi dibandingkan menggunakan substrat glukosa.Kata Kunci: Asam lemak volatil, fruktosa, glukosa, PHA, P(3HB-co-3HV), Ralstonia eutropha
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Ermaya, Dewi, Anshar Patria, Fadlan Hidayat, and Fachrul Razi. "Pengembangan Minyak Nilam Sebagai Aromaterapi Dan Potensinya Sebagai Produk Obat." Rona Teknik Pertanian 12, no. 2 (October 1, 2019): 58–63. http://dx.doi.org/10.17969/rtp.v12i2.14612.
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Abstrak. Aromaterapi adalah suatu bentuk terapi atau pengobatan menggunakan bahan tanaman volatil, yang bertujuan untuk mengatur fungsi kognitif, mood, dan kesehatan. Tanaman volatil dikenal juga minyak atsiri. Minyak atsiri biasa diperoleh dari tanaman dengan berbagai cara yang berbeda-beda seperti ekstraksi, penyulingan dan distilasi fraksinasi. Salah satu minyak atsiri adalah minyak nilam. Kandungan minyak nilam yang utama yaitu patchouli alcohol (40-50%) digunakan sebagai bahan baku, bahan pencampur dan fixative (pengikat wangi-wangian) dalam industri parfum, kosmetik, dan obat-obatan. Pengembangan minyak atsiri sebagai aromaterapi perlu dilakukan sebagai upaya peningkatan pemanfaatan dari produk minyak atsiri. Komponen aroma dari minyak atsiri cepat berinteraksi saat dihirup. Penelitian ini dilakukan untuk mengukur aktifitas lokomotor pada mencit untuk melihat efek yang ditimbulkan setelah di inhalasi dengan minyak nilam. Hasil menunjukkan adanya penurunan aktifitas setelah diinhalasi dengan minyak nilam. Ini menunjukkan minyak nilam memberikan efek depresi sistem syaraf pusat terhadap mencit. Persentase penurunan aktifitas gerak terbesar pada dosis 0,5 ml.Development of Patchouli Oil as Aromatherapy and Its Potential as Medicinal ProductsAbstract. Aromatherapy is a form of therapy or treatment using material from a volatile plant, intended to regulate cognitive, mood, and health function. Volati is also known for essential oil. Essential oil is often obtained from plants in various ways such as extraction, distillation and distillation of fractures. One essential oil is patchouli oil. The primary patchouli oil content is alcohol (40-50%), which is used as a ingredient, mixative and fixative in the perfume, cosmetics, and drugs industry. Commercial loans grew by 14 percent to RPM from the same period last year. Essential oil scent components must interact quickly when inhaled. The study was done to measure the locomotive activities of er er er to see the effect that was caused after inhalation with patouli oil. Results indicate a decrease in activity following inhalation with sapphire oil. This suggests patchouli oil, giving a depressed effect of the central nervous system on chiming. It's the largest drop in activity at a 0.5 ml dose.
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Norri, Juhani. "Volaten and Volating: Two Ghost Words in the Middle English Dictionary." Notes and Queries 64, no. 3 (September 1, 2017): 385–86. http://dx.doi.org/10.1093/notesj/gjx092.
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Lada, Yulius Gae, Supriyanto Supriyanto, and Purnama Darmadji. "PENGARUH PERENDAMAN BIJI KAKAO KERING DAN BAHAN ALAT SANGRAI TERHADAP SIFAT FISIK DAN PROFIL SENYAWA VOLATIL KAKAO SANGRAI SERTA SIFAT SENSORIS COKELAT BATANG YANG DIHASILKAN." Jurnal Agritech 34, no. 04 (February 11, 2015): 439. http://dx.doi.org/10.22146/agritech.9439.
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This research aimed at evaluating the effect of dry cocoa bean soaking and roasting using various type of materials roaster instrument on the physical properties and profile of volatile compounds of roasted beans as well as sensorial attributes of chocolate bar resulted. Dry beans were soaked into water for 2 h to reduce acidity. Roasting was carried outusing several instruments that were made from aluminum, iron and clay to obtain bean moisture content of 2 – 3.5%. Texture, color, and volatile compounds profile of roasted beans as well as sensorial attributes of chocolate bar were studied. Results showed that roasting cooking period (50 minutes) using clay roasting instrument was faster and hadhighest rate of temperature increase, followed by iron (70 minutes) and aluminum (90 minutes). Dry beans soaking significantly affected beans color (L* and λE value), chocolate bar attributes particularly aroma, acid taste and bitterness, however the instrument material differences had no significant effect on those parameters. The texture of cocoa beansroasted using a roaster of aluminum was the hardest, but it was not affected by the soaking treatment. Roasting of the cocoa beans using a roaster of aluminum, iron and clay produced different profiles on volatile compounds. A roaster of clay produced groups of compounds with the total area of SPME-GC-MS chromatogram was smaller than the roasterof aluminum and iron. The produced chocolate bars through the soaking treatment and roasting using a roaster of clay was preferred by the panelists.Keywords: Soaking, materials of roaster instrument, roasted cocoa beans, volatile compounds profile, chocolate bar ABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh perendaman biji kakao kering dan penyangraian menggunakan berbagai jenis bahan alat sangrai terhadap sifat fisik dan profil senyawa volatil kakao sangrai serta sifat sensoris cokelat batang yang dihasilkan. Biji kakao kering direndam menggunakan air selama 2 jam untuk mengurangi keasaman,kemudian disangrai menggunakan berbagai jenis bahan alat sangrai (alumunium, besi dan tanah liat) hingga kadar air biji kakao sangrai mencapai 2 – 3,5%. Biji kakao kering diamati dan dianalisis sifat fisik dan profil senyawa volatil biji kakao sangrai serta sifat sensoris cokelat batang. Hasil penelitian menunjukkan bahwa penggunaan alat sangrai dari tanah liat lebih cepat dalam mematangkan biji kakao kering menjadi biji sangrai (50 menit) dengan laju peningkatan suhu yang cepat dan tinggi, selanjutnya diikuti dengan alat sangrai yang terbuat dari besi (70 menit) dan alumunium (90 menit). Perlakuan perendaman biji kakao kering berpengaruh nyata terhadap warna biji sangrai (nilai L* dan λE)dan sifat sensoris cokelat batang yang dihasilkan terutama aroma cokelat, rasa asam dan pahit, sedangkan perlakuan bahan alat sangrai tidak berpengaruh nyata. Tekstur biji kakao dari hasil penyangraian menggunakan alat sangrai dari alumunium adalah paling keras, tetapi tidak dipengaruhi oleh perlakuan perendaman. Penyangraian biji kakaomenggunakan alat sangrai dari alumunium, besi dan tanah liat menghasilkan profil senyawa volatil yang berbeda. Dari kromatogram SPME-GC-MS diketahui bahwa alat sangrai dari tanah liat menghasilkan kelompok senyawa dan total luas area yang lebih kecil dibandingkan dengan alat sangrai dari alumunium dan besi. Cokelat batang yang dihasilkan melalui perendaman dan disangrai menggunakan alat sangrai dari tanah liat adalah yang paling disukai oleh panelis.Kata kunci: Perendaman, bahan alat sangrai, biji kakao sangrai, profil senyawa volatil, cokelat batang
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Rumape, Opir, Erni Mohamad, and Rindi Antika Mohi. "Optimasi Briket Bungkil Jarak Pagar (Jatropha Curcas) Melalui Variasi Tepung Tapioka." Jambura Journal of Chemistry 1, no. 1 (March 20, 2019): 1–5. http://dx.doi.org/10.34312/jambchem.v1i1.2103.
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This research was aimed to synthesis and charaeterization of bio briquette from jathropa as fuel alternative. It was tested froxmite malysis and through variation of sharch. The res showed that briquette of jathropa head 7,837% of moisture content, 5,993% of ash, 50,900% volatile compounds, density and 7027,322- 6120,711 kal/g of calorifie value.Keywords: Jatropha, biobriket characteristics, test proximate, tapiocaPenelitian ini bertujuan untuk mengetahui proses pembuatan briket jarak pagar melalui variasi tepung tapioka sebagai bahan alternatif, melalui tahapan penelitian yang meliputi pembuatan briket yaitu pengeringan, karbonasi, dan pencetakan. Karakterisasi briket meliputi uji proksimasi yakni kadar air, kadar abu, kadar senyawa volatil, kadar karbon terikat, kerapatan dan nilai kalor. Dari hasil uji proksimasi menunjukkan bahwa briket dari bungkil jarak pagar memperoleh rata-rata 7,837 %. untuk kadar air, rata-rata 5,993 %. untuk kadar abu, rata-rata 50,900% untuk kadar senyawa volatil, 7027,322 -6120,711 kal/g untuk nilai kalor.Kata kunci: Jarak pagar, karakteristik biobriket, uji proksimasi, tepung tapioka
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Tichá, I. "Viable strategies in volatile times." Agricultural Economics (Zemědělská ekonomika) 55, No. 5 (June 1, 2009): 229–32. http://dx.doi.org/10.17221/29/2009-agricecon.
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The article aims at the description and assessment of strategic options for companies which have necessary resources to take the advantage of the current economic downturn. The theoretical framework is based on two predominant approaches to competitive advantage and the practical implications for actions to be adopted are derived from the recommendations published recently by the leading consulting firms. While quick fixes ensuring a short-term survival (mostly financially based cost-saving measures) are an essential first step, a longer-term success lies in the effective adoption of the scenario-planning techniques, active competitors intelligence and a proactive attitude to restructuring through a combination of mergers, acquisitions and divestment decisions.
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Kasiotis, Konstantinos M. "Propolis non-volatile constituents: A Review." Hygeia:journal for drugs and medicines 6, no. 1 (April 3, 2014): 111–21. http://dx.doi.org/10.15254/h.j.d.med.6.2014.128.
Full textDissertations / Theses on the topic "Volatif"
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Guichard, Valérie. "Le safran, une culture à développer dans le sud-ouest : les constituants volatils et leur analyse par CPG dans différents organes." Bordeaux 2, 1993. http://www.theses.fr/1993BOR2P112.
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Ebrahimzadeh, Mousavi Seyed Mohamad Ali. "Migration de molécules volatiles dans un système aliment emballage bois : modélisation des transferts et mesure des coefficients de diffusion." Vandoeuvre-les-Nancy, INPL, 1998. http://docnum.univ-lorraine.fr/public/INPL_T_1998_EBRAHIMZADEH_MOUSAVI_S_M_A.pdf.
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La contamination des aliments peut résulter de diverses interactions entre les aliments emballés et les matériaux d'emballage, notamment de la migration de faibles quantités de composés constituants ces matériaux. Elle est importante des points de vue économique et sanitaire. Cette étude consiste en identification de composés volatils du bois de peuplier et en la détermination de leur diffusivité dans des aliments modèles et des aliments réels. Les modèles mathématiques développés pour prédire le taux de migration des composés volatils, à partir du peuplier vers des aliments de géométries différentes, ont permis d'estimer la concentration des composés migrant dans l'aliment emballé. Différents systèmes d'emballage ont été simulés pour le dosage expérimental de composés migrant dans le produit emballé. L’ensemble des résultats expérimentaux confirme la validité des modèles et des algorithmes de calcul proposés dans cette étude.
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Hillaire, Anne. "Étude de la récupération de composés organiques volatils d'effluents gazeux par perméation de vapeur à travers des membranes denses." Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL115N.
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La perméation de vapeur, procédé de séparation utilisant des membranes denses constitue une alternative attrayante pour épurer les effluents gazeux faiblement chargés en composés organiques volatiles (COV). Son principe repose sur l'extraction préférentielle de composés organiques, qui présentent une meilleure affinité pour le polymère, le transfert de matière étant rendu possible par une différence de pression imposée de part et d'autre de la membrane. Une cinquantaine d'unités industrielles sont déjà en fonction principalement pour traiter des hydrocarbures mais les connaissances théoriques et la compréhension des phénomènes permettant un dimensionnement rationnel sont encore insuffisantes. L’objectif de ce travail est d'étudier l'extraction de solvants oxygénés (acétone et acétate de méthyle) de l'air à l'aide de membranes de polydiméthylsiloxane (PDMS). La compréhension du mécanisme global de transfert à travers la membrane imposait une étude approfondie de la sorption, comprenant une analyse des mesures expérimentales et une tentative de modélisation (binaire et ternaire) à l'aide de modèles existants. Une méthode récemment développée, utilisant la chromatographie en phase gazeuse pour évaluer les coefficients de sorption, à par ailleurs été expérimentée. D’autre part, le développement d'un nouveau test de cohérence thermodynamique applicable aux équilibres polymère réticule / solvant a permis la validation des résultats de sorption obtenus. Différents paramètres opératoires intervenant sur les performances du procédé ont ensuite été étudiés : le type de membrane, la nature du COV, la pression et la température. Finalement, la modélisation du procédé a été abordée : les modèles couramment proposés et une nouvelle approche ont été comparés et confrontés aux résultats expérimentaux obtenus. Les modèles ont enfin été mis à profit pour dimensionner un module de perméation, de manière simplifiée.
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Iamanaka, Beatriz Thie. "Avaliação da micobiota de grãos de café e dos metabolitos fungicos na qualidade da bebida." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255262.
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Orientador: Neura BragagnoloTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O café passa por vários processos até chegar a ser consumido como bebida e vários fatores contribuem para a sua qualidade final, dentre eles a população microbiana presente. A contaminação dos grãos pelos microrgranismos é diversificada, envolvendo a participação de bactérias, bolores e leveduras, com a predominância de um ou outro grupo, dependendo da etapa de processamento dos grãos. Existem evidências, ainda não conclusivas de que vários fungos presentes no café podem produzir uma série de compostos que podem vir a prejudicar a qualidade da bebida. Esta pesquisa teve como objetivos analisar a micobiota dos grãos obtidos em diferentes etapas da cadeia produtiva do café; investigar a produção dos compostos voláteis produzidos pelos isolados e o impacto dos mesmos na qualidade da bebida e; avaliar sensorialmente a bebida, correlacionando com os fungos presentes. A micobiota de 41 amostras de grãos de café cru, de duas regiões produtoras do Brasil, Cerrado Mineiro/MG e Piraju/SP foram analisadas. As amostras foram coletados do pé (cereja), do solo (varreção), do terreiro (maduro, seco e passas no pé e verde) e da tulha (estocagem) e comparados dois tipos de preparo dos grãos: secagem natural e cereja descascado. As amostras de Minas Gerais apresentaram baixa infecção fúngica, as principais espécies isoladas foram Eurotium spp. e Fusarium spp. Em relação aos cafés da região de Piraju, houve uma grande diversidade de espécies isoladas, dentre àquelas mais predominantes foram Penicillium brevicompactum, Aspergillus foetidus, Penicillium crustosum e Fusarium spp. Cafés varreção e bóia (seco e passas no pé) caracterizaram-se pela alta incidência de Aspergillus foetidus, apresentando infecção superior a 16% por esta espécie e avaliação sensorial negativa. A foetidus produziu compostos voláteis, como 2-butenal, dimetilbisulfeto no meio de cultura e 1-octen 3-ol quando inoculado no café cru. Estes metabólitos são caracterizados pelo aroma desagradável de terra, mofo, estragado e pungente e foram relacionados como alguns dos compostos responsáveis pelas características negativas na análise sensorial da bebida. Foi constatado também que a presença de algumas espécies fúngicas nos grãos, mesmo em alta percentagem de infecção, não implicou necessariamente na redução da qualidade sensorial da bebida. Amostras com alta freqüência de Penicillium brevicompactum apresentaram avaliação final positiva. Esta espécie destacou-se pela produção de vários compostos voláteis com características positivas como aldeídos (2-octenal, decanal e undecanal) com aroma cítrico e herbal, e cetonas (2-nonanona, 3-nonen-2 ona, 2-undecanona e 2 pentadecanona) de aroma frutal e floral. Portanto, metabólitos produzidos durante o desenvolvimento de espécies fúngicas podem estar relacionados à introdução de características sensoriais de sabor ao café, tanto desejáveis quanto indesejáveis
Abstract: Coffee goes through several processes until consumed as a beverage and many factors contribute to its final quality, including the presence of the microbial population. The coffee beans contamination by microorganisms is diversity envolving bacteria, moulds and yeast, with predominance of one or another and is dependent of the coffee beans processing stages. There is inconclusive evidence that many fungi present in coffee can produce several volatile metabolites that can damage beverage quality. This research had the objectives to analyze the mycobiota ot the coffee beans obtained on the different stages of coffee production chain; investigate the production of volatile compounds produced by the isolates and the impact of them on the beverage quality and carry out sensory evaluation of beverage in relation to the fungal species. The mycobiota of forty-one samples of raw coffee beans from two Brazilian production areas, Cerrado Mineiro/MG and Piraju/SP were analyzed. Samples were collected from the tree (cherry beans), from the soil (¿varreção¿), from the drying yard (ripe, dry, over-ripe and immature) and drying storage (¿tulha¿) and two kinds of bean separation were compared: natural and pulped. The Minas Gerais samples had low fungal infection with the main species being Eurotium spp and Fusarium spp. In relation to the Piraju samples there was a considerable diversity of isolated species and the following were among the most predominant: Penicillium brevicompactum, Aspergillus foetidus, Penicillium crustosum and Fusarium spp. Coffee beans collected from the soil along with the over-ripe ones were a highly incidence of Aspegillus foetidus with a percent infection above 16% and a negative sensorial evaluation. Aspergillus foetidus produced volatile compounds such as 2-butenal, dimethyl dissulfite in the culture medium and 1-octen-3-ol when inoculated on the raw coffee. These metabolites were characterized by as unpleasant aroma of soil, musty, rotten and pungency and they were related as one of the responsible compounds for the negative characteristcs of the sensorial analyses.In this work the presence of some fungal species were found in the beans wich even at high levels of infection, did not necessarily result in a decrease of the sensorial evaluation. Samples with a high percentage of Penicillium brevicompactum infection had a positive final evaluation. This specie stood out from the rest due to the production of many volatile compounds with positive characteristics such as aldehydes (2-octenal, decanal and undecanal) showing citric and herbal aromas and cetones (2-nonanone, 3-nonen-2-one, 2-undecanonc and 2-pentadecanone) showing frutal and floral aroma. Therefore, metabolites produced during fungal growth can be related to the insertion of sensorial properties of flavour on coffee, both positive or negative
Doutorado
Doutor em Ciência de Alimentos
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Mermet, Kenneth. "Caractérisation physico-chimique et réactivité d'espèces biogéniques sur un site de mesure en forêt des Landes : impacts sur la qualité de l'air." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0363.
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A l’échelle globale, les forêts sont parmi les écosystèmes les plus émetteurs de composés organiques volatils (COV). Une fois émis dans l’atmosphère, ces COV vont rapidement être oxydés en composés oxygénés. Selon leur volatilité et leur réactivité, ces produits d’oxydation pourront eux-mêmes être oxydés et rester soit en phase gazeuse et/ou être transférés dans la phase particulaire pour former des aérosols organiques secondaires (AOS). Cette thèse a eu pour objet principal de mieux caractériser les COV biogéniques (COVBs) en forêt des Landes, leurs concentrations et plus particulièrement leur réactivité avec les différents oxydants atmosphériques (i.e. le radical hydroxyle (OH), l’ozone (O3) et le radical nitrate (NO3)), afin d’identifier les principaux précurseurs de la formation des AOS biogéniques, au sein d’une forêt de pins maritimes. Le développement d'une nouvelle méthodologie chromatographique en phase gazeuse a permis la mesure spéciée et en ligne de 20 COVB comprenant l’isoprène, l’α- et le β-pinène, le 2 et le Δ3- carène, l’α- et le γ-terpinène, le linalool, le camphène, etc. Cette analyseur ainsi que d’autres instruments permettant la mesure de gaz traces et d’aérosols ont été utilisés au cours de l’été 2017 dans le cadre de la campagne intensive LANDEX, dans l’une des plus grandes forêts monospécifique d’Europe (>95% Pinus pinaster). Une analyse en composante principale des données météorologiques et des mesures en COVB, obtenues pendant la campagne a permis de montrer que les concentrations en COVB étaient principalement dépendantes de leurs émissions, de la température, de l'irradiation solaire et de la stabilité atmosphérique. L’analyse de la réactivité des COVB avec les principaux oxydants atmosphériques a permis de montrer le contraste entre le jour, où elle est principalement liée au radical OH et la nuit, où les processus d'ozonolyse dominent. Enfin, il a été mis en évidence que l’ozonolyse du β-caryophyllène, de l’α-pinène, du myrcène, et du linalol et l’oxydation de l’isoprène par le radical OH, étaient les principales sources de composés oxygénés, précurseurs d'AOS, en forêt des LandesAt the global scale, forests are the largest emitters of VOCs. Once released into the atmosphere, VOCs will be fastly oxidized to oxygenated compounds. Depending on their volatility and reactivity, these oxidation products may themselves be re-oxidized, remain in the gas phase and/or be transferred to the particulate phase to form secondary organic aerosols (SOAs). This thesis aimed to better characterize biogenic VOC concentrations (BVOCs) and more especially their reactivity with atmospheric oxidants (i.e. the hydroxyl radical (OH), ozone (O3) and the nitrate radical (NO3)), in order to identify the main precursors of SOA formation within a maritime pine forest. The metrological development of a gas chromatographic analyzer has made possible the online and specified measurement of 20 BVOCs including isoprene, α- and β-pinene, 2 and Δ3-carene, α- and γ-terpinene, linalool, camphene, etc. This analyzer and some other instruments for the measurement of trace gases and aerosols were used during the summer of 2017 as part of the LANDEX intensive campaign in one of the largest pine forests in Europe (> 95% Pinus pinaster) located in the southwest of France. A principal component analysis of meteorological data and BVOC measurements showed that BVOC concentrations were mainly dependent on their emissions, the ambient temperature, the solar irradiation and the atmospheric stability. The analysis of the reactivity of the identified VOCs with the main atmospheric oxidants has helped to show the contrast between processes involving OH radical during daytime and ozonolysis at night. Finally, it was determined that the ozonolysis of β-caryophyllene, α-pinene, myrcene, and linalool, and the OH initiated oxidation of isoprene were the main sources of oxidation products, as SOA precursors, within the Landes forest
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Miguet, Marianne. "Adsorption de COV issus d'eaux souterraines et régénération des charbons actifs par voie solaire." Thesis, Perpignan, 2015. http://www.theses.fr/2015PERP0029/document.
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Ce manuscrit s’intéresse à une filière globale et durable de dépollution des eaux souterraines. Le polluant cible, le tétrachloroéthylène, est un composé organique volatil. La première étape de cette filière est la séparation du contaminant de l’eau. Elle a été réalisée par adsorption sur charbons actifs dans une colonne en lit fixe. Les résultats obtenus en laboratoire sur les capacités et les cinétiques d’adsorption ont permis de montrer l’efficacité de ce procédé. Un modèle issu de ces expériences a représenté correctement des conditions opératoires variées correspondant à celles utilisées dans l’industrie. Ce modèle a été validé par un pilote préindustriel installé sur site et fonctionnant en conditions réelles. La gestion des charbons actifs chargés en polluant a été étudiée. La régénération thermique a été privilégiée. Cette opération présente l’intérêt de rétablir les capacités d’adsorption des carbones activés et de récupérer les polluants en phase liquide. Bien que préférable à la production d’adsorbants, elle pourrait encore être plus durable et compétitive économiquement en effectuant le traitement thermique par voie solaire. Il a été montré que le taux de régénération est le même pour les régénérations solaire et classique. Il est donc possible, dans le cas du tétrachloroéthylène, de remplacer une source d’énergie fossile par le soleil. La solution de distillat obtenue lors de la régénération peut être minéralisée par photocatalyse hétérogène. Cette opération a été réalisée en laboratoire avec une lampe reproduisant le spectre solaire. La faisabilité de la photocatalyse solaire sur le résidu issu de cette filière de dépollution a ainsi été montréeThis manuscript focuses on a comprehensive and durable treatment of polluted groundwater. The target contaminant, tetrachlorethylene, is a volatile organic compound. The first step in the treatment is the separation of contaminants. It was carried out by adsorption on activated carbons in a fixed bed column. The results obtained in the laboratory on the adsorption capacity and kinetics have shown the efficiency of this process. A mathematic model represented properly the various operating conditions corresponding to those used in the industry. This model has been validated by a pre-industrial pilot installed onsite and operating in real conditions. Management of spent activated carbons was studied. The thermal regeneration was chosen because it has the interest to restore the adsorption capacity of adsorbents and to collect the pollutants in a liquid phase. Although preferable to the production of activated carbons, it could still be economically more competitive and more sustainable by performing the heat treatment by solar means. It has been shown that the regeneration rate is the same for the solar and classical regenerations. It is therefore possible, in the case of tetrachlorethylene, to replace a fossil energy source by the sun.The distillate solution obtained during the regeneration can be mineralized by heterogeneous photocatalysis. This operation was carried out in the laboratory with a lamp reproducing the solar spectrum. The feasibility of solar photocatalysis on the final residue of the water treatment has been shown
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Le, Gall Nolwenn. "Ascension et dégazage des magmas basaltiques : approche expérimentale." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2044/document.
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Afin de parvenir à une meilleure compréhension de la dynamique d’ascension et d’éruption des magmas basaltiques, nous avons réalisé des expériences de décompression à haute pression (200–25 MPa) et haute température (1200°C) spécifiquement orientées pour documenter la nucléation des bulles de gaz ; ce processus, qui constitue la première étape du dégazage magmatique, conditionne l’évolution de la phase gazeuse (force motrice des éruptions explosives) dans le conduit volcanique. Quatre principaux ensembles d’expériences ont été menés afin de mieux comprendre le rôle des volatils majeurs (H2O, CO2, S), ainsi que les effets de la vitesse d’ascension et de la présence de cristaux sur la cinétique de vésiculation (nucléation, croissance, coalescence) des bulles dans les magmas basaltiques. L’objectif est de comprendre les mécanismes qui contrôlent les caractéristiques texturales (nombre, taille, forme des bulles) et chimiques (teneur en volatils dissous, composition des gaz) des produits naturels et de les approcher expérimentalement. Dans ce sens, les verres expérimentaux ont été analysés avant et après décompression sur le plan textural (microtomographie par rayons X, MEB) et chimique (FTIR, microsonde électronique). Nos résultats démontrent une forte influence du CO2 sur les processus ainsi que sur le mode (équilibre vs. déséquilibre) de dégazage des magmas basaltiques, en lien avec des différences de solubilité et de diffusivité entre les espèces volatiles. Nos données, obtenues dans des conditions voisines des conditions naturelles, ont des implications volcanologiques pour l’interprétation des textures de bulles et des mesures de gaz en sortie de conduit, ainsi que, plus spécifiquement, pour la dynamique des éruptions paroxysmales au StromboliFor a better understanding of the dynamics of ascent and eruption of basaltic magmas, we have performed high pressure (200–25 MPa) and high temperature (1200°C) decompression experiments specifically oriented to document gas bubble nucleation processes. Bubble nucleation occurs first during magma degassing and, so, it is critical to understand bubble nucleation processes to constrain the evolution of the gas phase (which is the driving force of explosive eruptions) in the volcanic conduit. Four main sets of experiments were conducted to better assess the role of the major volatiles (H2O, CO2, S), as well as the effects of ascent rate and crystals, on bubble vesiculation (nucleation, growth, coalescence) kinetics in basaltic magmas. The aim of the study is to understand the mechanisms which control the textural (number, size, shape of bubbles) and the chemical (dissolved volatile concentrations, gas composition) characteristics of natural products, and also to approach them experimentally. In this way, experimental melts, before and after decompression, were analysed texturally (by X-ray microtomography and MEB) and chemically (by FTIR and electron microprobe). Our results demonstrate a strong influence of CO2 on degassing mode (equilibrium vs. disequilibrium) and mechanisms, which are shown to be controlled by differences in solubility and diffusivity between the main volatile species. Finally, our data, obtained under conditions closely approaching natural eruptions, have volcanological implications for the interpretation of bubble textures and gas measurements, as well as, more specifically, for the dynamics of Strombolian paroxysms
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Sutter, Benjamin. "Étude de l'évaporation d'aérosols liquides semi-volatils collectés sur médias fibreux." Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL067N/document.
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Cette étude s’inscrit dans le cadre de l’amélioration des connaissances liées à l’évaporation d’aérosols liquides semi-volatils collectés sur des filtres à fibres. Le phénomène d’évaporation d’aérosols collectés sur médias fibreux induit des problèmes de sécurité avec notamment une surexposition des salariés aux vapeurs, à l’aval des systèmes généraux de filtration de l’air. De plus, lors des contrôles des concentrations atmosphériques des aérosols, l’évaporation induit une sous-estimation de la phase particulaire de l’aérosol prélevé qui est problématique en termes de prévention de l’exposition. L’objectif de ces travaux a donc été de produire de nombreux résultats expérimentaux afin, d’une part, de compléter les rares présents dans la littérature et, d’autre part, d’améliorer les modèles théoriques développés précédemment. Deux approches expérimentales ont été menées afin d’identifier le processus d’évaporation d’un aérosol collecté. La première, nommée approche globale, permet de suivre l’évaporation de l’aérosol par la quantification des vapeurs à l’aval du filtre, au cours du temps. La seconde, nommée approche microscopique, étudie l’évaporation de gouttes collectées sur les fibres d’une fibre à l’échelle microscopique. Les deux approches réalisées lors de ces travaux s’accordent sur le fait que l’évaporation d’un aérosol liquide semi-volatil ne peut être modélisée par les modèles proposés par la littérature. Des hypothèses ont été avancées afin d’expliquer la divergence de cinétique d’évaporation entre la théorie et les expérimentationsThis study falls within the scope of improving knowledge concerning evaporation of semi-volatile liquid aerosols collected on fibrous filters. Under these conditions, the aerosol evaporation phenomenon causes problems of safety, in particular over-exposure of employees to vapours downstream of general air filtering systems. Furthermore, when controlling aerosol atmospheric concentrations, evaporation results in under-estimation of the sampled aerosol particle phase and this is clearly problematic in exposure prevention terms. The aim of this work was therefore to record a large number of experimental data, both to make up for their scarcity in the literature and to improve previously developed theoretical models. Two experimental approaches were implemented to identify the evaporation process for a collected aerosol. The first, termed the global approach, allowed us to monitor aerosol evaporation by measuring vapour quantity downstream of the filter with respect to time. The second, microscopic, approach considers evaporation of droplets collected on the filter fibres on a microscopic scale. The two approaches implemented during this research lead to agreement on the fact that evaporation of a liquid semi-volatile aerosol cannot be satisfactorily represented by the theoretical models proposed in the literature. Hypotheses are advanced to explain the divergence in evaporation kinetics between theoretical and experimental work
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Ogeskär, Tobias. "Forensisk analys av volatilt minne från operativsystemet OS X." Thesis, Högskolan Dalarna, Datateknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:du-17319.
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Behovet av att analysera volatilt minne från Macintosh-datorer med OS X har blivit allt mer betydelsefull på grund av att deras datorer blivit allt populärare och att volatil minnesanalysering blivit en allt viktigare del i en IT-forensikers arbete. Anledningen till att volatil minnesanalysering blivit allt viktigare är för att det går att finna viktig information som inte finns lagrad permanent på datorns interna hårddisk. Problemet som låg till grunden för det här examensarbetet var att det uppenbart fanns brist på undersökningsmetoder av det volatila minnet för Mac-datorer med OS X.Syftet med detta arbete var därför att undersöka möjligheten att utvinna information från ett volatilt minne från en Mac-dator med OS X genom att kartlägga och bedöma olika undersökningsmetoder. För att göra denna undersökning har litteraturstudier, informella intervjuer, egna kunskaper och praktiska försök genomförts.Slutsatsen blev att möjligheten att utvinna information från det volatila minnet från en Mac-dator med OS X är relativt begränsad. Det största problemet är själva dumpningen av minnet. Många av dumpningsmetoderna som finns att tillgå kräver administrativa rättigheter. Vid analysering av en minnesdump bör man aldrig förlita sig på en analysmetod då olika analysmetoder ger olika resultat som kan vara till nytta för en vidare undersökning av en Mac-dator.The need to analyze volatile memory on Macintosh computers with OS X has become increasingly important due to the fact that their computers have become more popular and volatile memory analysis has become a more important part of an IT-forensics work. The reason volatile memory analysis has become more important is that it's possible to find information that’s not stored permanently on the computer’s hard drive. The problem that formed the basis for this thesis was that it was obvious there was a lack of methods of investigation of the volatile memory for Macs running OS X.The aim of this work was therefore to investigate the possibility of extracting information from a volatile memory from a Mac computer with OS X by identifying and assessing different methods of investigation. To do this investigation, literature studies, informal interviews, own knowledge and practical attempts have been conducted.It was concluded that the ability to extract information from the volatile memory from a Mac-computer with OS X is relatively limited. The biggest problem is the dumping of the memory. Many of the available dumping methods require administrative rights. When analyzing a memory dump you should never rely on one analyze method since different analyze methods give different results that can be useful for further investigation of a Mac-computer.
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Dutra, Camila Braga. "Determinação de nitrosaminas volateis em salsichas "hot dog"." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256306.
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Orientador: Felix Guillermo Reyes ReyesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Nitrito e nitrato são os principais ingredientes usados no processo de cura conferindo aroma e cor avermelhada caracteristicos dos produtos curados como, por exemplo, a salsicha e atuando como antioxidantes e antimicrobianos, impedindo o crescimento de Clostridium botulinum. O efeito tóxico mais relevante da presença de nitrato e nitrito é a formação de nitrosaminas as quais são compostos N-nitroso que podem ser formados da reação de agentes nitrosantes com aminas secundárias ou terciaérias. a maior exposição a estes compostos acontece através dos alimentos, onde o modo de preparo e processamento tem grande influência na quantidade de nitrosaminas presente no alimento, sendo que a formação de nitrosaminas durante o processamento pode ser reduzida por incorporação de inibidores, tais como, ácido ascórbico ou xtocoferol. A nitrosaminas voláteis são as que mais ocorrem em alimentos, e são potentes carcinógenos em animais de laboratório induzindo tumores em vários orgãos. O propósito do presente estudo foi otimizar e validar o método de amostragem "headspace" por microestração em fase sólida (SPME, do inglês Solid Phase Microextraction) usando cromatografia gasosa acoplada a um dectector de quimioluminescência ) TEA, do inglês Thermal Energy Analyser) para a determinação de nitrosaminas voláteis em salsichas "hot-dog". As amostras foram adquiridas bo comércio da cidade de Campinas, São Paulo. Nas amostras analisadas não foram encontradas nitrosaminas voláteis em níveis detectáveis. Diferentes modos de preparo, como cozimento em água e fritura, não contribuíram para a formação de nitosaminas. Os resultados indicam a ausência de nitrosaminas nas amostras analisadas devido, possivelmente, aos baixos teores de nitrito disponível para a reação com as aminas prsentes na carne e/ou pela ação efetiva do ascorbato de sódio atuando como inibidor da formação de nitrosaminas
Abstract: During the curing process, nitrite and nitrate are the principal ingridients udes for curing. They confer and colored color characteristic of the cured meat as sausage, and act as antioxidants and antimicrobial, comtrolling the growth of Clostridium botulinum. The most important toxic effect of the presence of nitrate and nitrite is the formation of nitrosamines. These are N-nitroso compounds that can be formed by the reaction of the nitrosating agents with secundary or tertiary amines. The major exposure to these compounds happens through foodstuffs, where the procedures of preparation and processing have great influence in the present amount of nitrosamines in the food. The formation of nitrosamines during the processing can be reduced by incorporation of inhibitors, such as, ascorbic acid or x-tocoferol. The volatile nitrosamines are the ones that occur in foods more frequentely, and are strong carcinogens in laboratory animals inducing tumors in a variety of organs. The purpose of the present study was to optimize and to validate a simple method using headspace sampling by solid-phase microextraction gas chromatography with thermal energy analyzer detector (HS-SOME-GC-TEA) for the determination of volatile nitrosamines in hot-dog sausages. The samples were purchased from local markets (Campinas, São Paulo). In the analyzed samples volatile nitrosamines have not been found in detectable levels. Different cooking procedures, as boiled in water and frying, did not contributr to the formation of nitrosamines. The results indicate the absence of nitrosamines in the samples nalyzed possibly because of low content of available nitrite for the reaction with the amines found in the meat and because of the action of dodium ascorbate acting as inhibitor for the formation of nitrosamines
Mestrado
Mestre em Ciência de Alimentos
Books on the topic "Volatif"
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Zelinová, Hana. Volanie vetra. 4th ed. Bratislava [Slovakia]: Slovenský spisovatelʹ, 1986.
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F, Bennett Andrew, and Field Barry, eds. Volatile organic compounds. London: HMSO, 1995.
Find full textBook chapters on the topic "Volatif"
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Cleaves, Henderson James. "Volatile." In Encyclopedia of Astrobiology, 1753. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_1669.
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Cleaves, Henderson James. "Volatile." In Encyclopedia of Astrobiology, 1. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_1669-3.
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Gooch, Jan W. "Volatile." In Encyclopedic Dictionary of Polymers, 801. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_12636.
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Cleaves, Henderson James. "Volatile." In Encyclopedia of Astrobiology, 2616. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_1669.
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Lacaze, Pierre Camille, and Jean-Christophe Lacroix. "General Issues Related to Data Storage and Analysis Classification of Memories and Related Perspectives." In Non-Volatile Memories, 1–12. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118789988.ch1.
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Lacaze, Pierre Camille, and Jean-Christophe Lacroix. "State of the Art of DRAM, SRAM, Flash, HDD and MRAM Electronic Memories." In Non-Volatile Memories, 13–57. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118789988.ch2.
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Lacaze, Pierre Camille, and Jean-Christophe Lacroix. "Evolution of SSD Toward FeRAM, FeFET, CTM and STT-RAM Memories." In Non-Volatile Memories, 59–91. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118789988.ch3.
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Lacaze, Pierre Camille, and Jean-Christophe Lacroix. "Volatile and Non-Volatile Memories Based on NEMS." In Non-Volatile Memories, 93–122. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118789988.ch4.
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Lacaze, Pierre Camille, and Jean-Christophe Lacroix. "Non-Volatile Phase-Change Electronic Memories (PCRAM)." In Non-Volatile Memories, 123–63. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118789988.ch5.
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Lacaze, Pierre Camille, and Jean-Christophe Lacroix. "Resistive Memory Systems (RRAM)." In Non-Volatile Memories, 165–99. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118789988.ch6.
Full textConference papers on the topic "Volatif"
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Dingler, Aaron, Vjiay Karthik Sankar, Steve Kurtz, Michael Niemier, Xiaobo Sharon Hu, Gyorgy Csaba, Joseph Nahas, Wolfgang Porod, Gary Bernstein, and Peng Li. "Making non-volatile nanomagnet logic non-volatile." In the 49th Annual Design Automation Conference. New York, New York, USA: ACM Press, 2012. http://dx.doi.org/10.1145/2228360.2228445.
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Casagrande, Giulio, and Shine Chung. "Non-Volatile Memory." In 2008 International Solid-State Circuits Conference - (ISSCC). IEEE, 2008. http://dx.doi.org/10.1109/isscc.2008.4523235.
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"Non-Volatile Memory." In 2006 IEEE International Solid-State Circuits Conference. Digest of Technical Papers. IEEE, 2006. http://dx.doi.org/10.1109/isscc.2006.1696076.
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Hidaka, Hideto, and Yair Sofer. "Non-Volatile Memories." In 2007 IEEE International Solid-State Circuits Conference. Digest of Technical Papers. IEEE, 2007. http://dx.doi.org/10.1109/isscc.2007.373498.
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Zhou, Wenjun, and Hui Xiong. "Volatile correlation computation." In the 14th ACM SIGKDD international conference. New York, New York, USA: ACM Press, 2008. http://dx.doi.org/10.1145/1401890.1401991.
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Baudet, Philippe, Sere Ser, Martine Auriol, Christophe Gourdon, and Isabelle Gibek. "Volatile liquid pressurization." In 37th Joint Propulsion Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2001. http://dx.doi.org/10.2514/6.2001-3830.
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El-Banbi, Ahmed H., and William D. McCain. "Sampling Volatile Oil Wells." In SPE Production and Operations Symposium. Society of Petroleum Engineers, 2001. http://dx.doi.org/10.2118/67232-ms.
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Bernstein, Mark, Jay David Bolter, Michael Joyce, and Elli Mylonas. "Architectures for volatile hypertext." In the third annual ACM conference. New York, New York, USA: ACM Press, 1991. http://dx.doi.org/10.1145/122974.122999.
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Braukmüller, Ninja, Claudia Funk, Carsten Münker, and Frank Wombacher. "Volatile Elements in Chondrites." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.256.
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Xue, Chun Jason, Youtao Zhang, Yiran Chen, Guangyu Sun, J. Jianhua Yang, and Hai Li. "Emerging non-volatile memories." In the seventh IEEE/ACM/IFIP international conference. New York, New York, USA: ACM Press, 2011. http://dx.doi.org/10.1145/2039370.2039420.
Full textReports on the topic "Volatif"
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Riviere, J. E., J. D. Brooks, G. L. Qiao, and N. A. Monteiro-Riviere. Percutaneous Absorption of Volatile Chemicals. Fort Belvoir, VA: Defense Technical Information Center, November 1997. http://dx.doi.org/10.21236/ada332910.
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Au, Tsz-Chiu, Ugur Kuter, and Dana Nau. Web Service Composition With Volatile Information. Fort Belvoir, VA: Defense Technical Information Center, January 2006. http://dx.doi.org/10.21236/ada448037.
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Research Institute (IFPRI), International Food Policy. How volatile are African food prices. Washington, DC: International Food Policy Research Institute, 2013. http://dx.doi.org/10.2499/9780896298170.
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Davison, Brian H., and John W. Barton. Biofiltration of Volatile Pollutants: Solubility Effects. Office of Scientific and Technical Information (OSTI), June 2001. http://dx.doi.org/10.2172/834467.
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Davison, Brian H., and John W. Barton. Biofiltration of Volatile Pollutants: Solubility Effects. Office of Scientific and Technical Information (OSTI), June 2002. http://dx.doi.org/10.2172/834468.
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Vogel, R. E. Sitewide railroad ties volatile organic package. Office of Scientific and Technical Information (OSTI), August 1994. http://dx.doi.org/10.2172/10187040.
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Laguna, G. R., F. J. Peter, A. D. Stuart, and V. M. Loyola. Volatile organic monitor for industrial effluents. Office of Scientific and Technical Information (OSTI), July 1993. http://dx.doi.org/10.2172/10177056.
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Gu, B., and R. L. Siegrist. Alkaline dechlorination of chlorinated volatile organic compounds. Office of Scientific and Technical Information (OSTI), June 1996. http://dx.doi.org/10.2172/419269.
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Smith, R. A. Volatile Components from Packing Matrials, Rev. 2. Office of Scientific and Technical Information (OSTI), March 2006. http://dx.doi.org/10.2172/974247.
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Campbell, Kristy A. Reconfigurable Electronics and Non-Volatile Memory Research. Fort Belvoir, VA: Defense Technical Information Center, November 2015. http://dx.doi.org/10.21236/ad1000558.
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