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UV reflectance photography of skin : what are you imaging ? / Jonathan M. Crowther in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 42, N° 2 (04/2020)
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Titre : UV reflectance photography of skin : what are you imaging ? Type de document : texte imprimé Auteurs : Jonathan M. Crowther, Auteur Année de publication : 2020 Article en page(s) : p. 136-145 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chimie analytique
Emulsions -- Emploi en cosmétologie
Formulation (génie chimique) -- Stabilité
Peau -- analyse
Photographie
Spectroscopie de réflectanceIndex. décimale : 668.5 Parfums et cosmétiques Résumé : - OBJECTIVE : Photography can be a powerful tool for researching the skin. Moving outside the visible spectrum and into the ultra violet (UV) presents a unique set of challenges to the skin photographer because of the restrictions imposed by the equipment being used. This article discusses these challenges in relation to camera sensitivity, lens and filter transmission and lighting spectrum, with the aim of demystifying what is actually being captured when imaging skin.
- METHODS : In addition to a discussion of existing data on the subject of camera sensor sensitivity, filter transmission and flash spectral analysis, transmission in the UV of a variety of camera lenses using a new method has been carried out.
- RESULTS : Using the described approach, lens transmission between 280 and 420 nm of a range of lenses has been measured. Combining this with camera sensor sensitivity data and filter and light source characteristics, it has been possible to determine an overall, harmonized, spectral sensitivity curve for what is being imaged with a given setup.
- CONCLUSIONS : UV reflectance photography, while a powerful tool, is often misunderstood and misreported as to what is actually being imaged. By combining measurements on camera sensitivity, lens and filter transmission and light source spectra the researcher can more fully understand what is they are actually measuring, thereby enabling better communication with the consumer on what they are seeing and a more complete description for any claims support.Note de contenu : - Factors to consider during equipment choice
- Lens transmission
- Filter transmission
- Light source
- Bringing it all together - harmonization
- Image format - Jpg or RAWDOI : https://doi.org/10.1111/ics.12591 Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=34504
in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE > Vol. 42, N° 2 (04/2020) . - p. 136-145[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 21862 - Périodique Bibliothèque principale Documentaires Disponible Verifying natural ingredients via carbon-14 testing / Jasmine Garside in PERSONAL CARE EUROPE, Vol. 11, N° 4 (09/2017)
[article]
Titre : Verifying natural ingredients via carbon-14 testing Type de document : texte imprimé Auteurs : Jasmine Garside, Auteur ; Anna Lykkeberg, Auteur Année de publication : 2017 Article en page(s) : p. 63-65 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biocosmétiques
Carbone 14
Chimie analytique
Cosmétiques -- Analyse
Ingrédients cosmétiquesIndex. décimale : 668.5 Parfums et cosmétiques Résumé : Although natural labelling in the beauty industry has traditionally been notoriously unregulated, the outcome of four recent legal cases in the US indicates that the Federal Trade Commission (FTC) is willing to hold a company accountable for "100% natural" or "all natural" claims and take action when a product labelled as such is found to contain synthetic ingredients. It is therefore in the commercial and legal interests of manufacturers to identify analytical tools that allow them to verify and measure the natural source before risking the bottom line and brand name.
The move toward plant-based ingredients places a greater responsibility on cosmetics manufacturers to test that raw materials purchased as 'natural' have not been adulterated and to substantiate claims on their final products through reproducible analyses such as carbon-14 testingNote de contenu : - Booming market for natural cosmetic products
- How does carbon-14 testing work for natural products ?
- Regulatory and labelling challenges when switching to natural
- Quality assurance: checking that 'natural' is indeed natural
- Is 100% natural a realistic goal?En ligne : https://drive.google.com/file/d/1bOiYH8Qn8T8UCqMdj-dwQji182x_Wvn_/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=29323
in PERSONAL CARE EUROPE > Vol. 11, N° 4 (09/2017) . - p. 63-65[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 19098 - Périodique Bibliothèque principale Documentaires Disponible VOC testing comparison : EPA method 24 versus the cal poly method / V. C. Bud Jenkins in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 67, N° 841 (02/1995)
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Titre : VOC testing comparison : EPA method 24 versus the cal poly method Type de document : texte imprimé Auteurs : V. C. Bud Jenkins, Auteur ; Joseph C. Reilly, Auteur ; Bob Sypowicz, Auteur ; Max T. Wills, Auteur Année de publication : 1995 Article en page(s) : p. 53-59 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Chimie analytique
Composés organiques volatils
Etudes comparatives
Revêtements en phase aqueuse:Peinture en phase aqueuseIndex. décimale : 667.9 Revêtements et enduits Résumé : The Cal Poly distillation modification of the Karl Fischer water determination of ASTM D 4017 gives accurate and precise water content of coatings and consequently better VOC values on waterborne paints. The precision appears to be substantially better than that obtained with previous methods. A relative reproductibility of 2.85% at the 95% confidence level was obtained on four coatings with water contents ranging from 32 to 72%. Azeotropic distillation of water with 1-methoxy-2-propanol followed by Karl Fischer titration of the distillate appears to be applicable to many different coatings types. The distillation offers several advantages, including the elimination of numerous potential interfering materials which are known to react with Karl Fischer reagent, the prevention to electrode fouling by polymer, and allows the use of the more general and extensively documented ASTM E 203 Karl Fischer titration method for water determination.
Mathematical modeling shows that waterborne coatings with greater than 60% water content or VOC contents lower than about 160 g/L are extremely difficult to analyze using the existing ASTM methods for VOC analysis from a precision standpoint in which 10% or better reproductibility is desired. The 10% allowance presently in use by many air quality agencies should be replaced by a sliding tolerance scale which reflects the specific parameters of coating formulations.
We suggest that the EPA and ASTM consider round-robin testing of the Cal Poly distillation method to confirm the results obtained in this study and to test the potential broader applicabillity of the method. We also suggest that Cal Poly evaluate extraction-dissolution water analysis (e.g., the Golton Method) and compare it against the distillation method in terms of accuracy, precision, and ease of use. The LASCT intends to initiate further studies to determine if the Cal Poly water method will reduce inaccuracies potentially caused by substances such as ammonia, ionic compounds, and additives, such as melamines and certain pigments.Note de contenu : - CAL POLY WATER METHOD : Procedure - Sample - Standard - Analysis and calculation
- VOC VALUES OBTAINED WITH KNOWN SAMPLES
- PREPARATION OF SAMPLES FOR ROUND-ROBIN ANALYSIS
- ROUND-ROBIN DISCUSSION
- CALCULATION OF THE VOC CONTENT
- FORMULA FOR CALCULATION OF COATING VOC CONTENTPermalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=18513
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 67, N° 841 (02/1995) . - p. 53-59[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 003488 - Périodique Bibliothèque principale Documentaires Disponible 003499 - Périodique Bibliothèque principale Documentaires Exclu du prêt Wet clay adhesion to antistick coatings : effects of binder type and surface roughness / Andrea Fasano in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 17, N° 1 (01/2020)
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Titre : Wet clay adhesion to antistick coatings : effects of binder type and surface roughness Type de document : texte imprimé Auteurs : Andrea Fasano, Auteur ; Liliana Madaleno, Auteur ; Svava Davidsdottir, Auteur ; Lars S. Jensen, Auteur ; Josep Palasi, Auteur ; Claus Erik Weinell, Auteur ; Kim Dam-Johansen, Auteur ; Søren Kiil, Auteur Année de publication : 2020 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Acier L'acier est un alliage métallique utilisé dans les domaines de la construction métallique et de la construction mécanique.
L'acier est constitué d'au moins deux éléments, le fer, très majoritaire, et le carbone, dans des proportions comprises entre 0,02 % et 2 % en masse1.
C'est essentiellement la teneur en carbone qui confère à l'alliage les propriétés du métal qu'on appelle "acier". Il existe d’autres métaux à base de fer qui ne sont pas des aciers comme les fontes et les ferronickels par exemple.
Angle de contact
Argile
Caractérisation
Chimie analytique
Frottements (mécanique)
Humidité
Liants
Matériaux cimentaires
Mesure
Métaux -- Revêtements
Revêtements anti-adhésion
RhéologieIndex. décimale : 667.9 Revêtements et enduits Résumé : The handling of sticky raw material can cause problems during operation of process equipment in the cement production industry. These handling problems are generally observed when raw material (e.g., wet clay) sticks to machine walls and causes blockage of outlets. This leads to frequent production shutdowns and expensive cleaning operations. In this work, the effects of surface material and process parameters on the friction forces between wet clay and surface were investigated. Various surface materials and clay impact speeds were investigated. The results demonstrate that not only the equipment surface material but also the surface roughness influences the observed frictional behavior. The ranking of the materials in terms of effective static friction coefficients fell in two groups with equal performance within the group: (1) Two Teflon-based coatings (Accofal 2G54 and Accolan LB), polished AISI 304 stainless steel, Matrox lining, and a polyurethane-based coating (best performing surfaces), (2) Mild steel, a silicone-based coating, and AISI 304 stainless steel (worst performing surfaces). However, the friction coefficients of the two groups only varied by a factor of two, suggesting that adhesion of wet clay to surfaces is difficult to avoid by the use of coatings. Note de contenu : - INTRODUCTION : Mechanisms of wet clay adhesion to surfaces
- PILOT PLANT DESIGN AND MEASUREMENT SYSTEM : Pilot plant design - Calculation of the effective static friction coefficient
- STEEL DISKS, LINING, AND COATINGS : Contact angle measurements
- CHARACTERIZATION OF THE CLAY USED : X-ray analysis of the clay - Particle size analysis of the clay - Chemical analysis of clay - Mineral composition of clay - Rheological analysis of clay - Water content of clay
- RESULTS AND DISCUSSION : Effect of clay lump mass - Effect of repositioning of clay lump - Effect of surface material - The combined effect of surface material and roughness - Contact angle measurementsDOI : 10.1007/s11998-019-00240-3 En ligne : https://link.springer.com/content/pdf/10.1007/s11998-019-00240-3.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=33728
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 17, N° 1 (01/2020)[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 21517 - Périodique Bibliothèque principale Documentaires Disponible