80 research outputs found
Ăšj laboratĂłriumi eszközök Ă©s tökĂ©letesĂtĂ©sek Budapest FĹ‘város VegyĂ©szeti Ă©s ÉlelmiszervizsgálĂł IntĂ©zetĂ©ben : IV. rĂ©sz
Élelmiszerszabványok vizsgálati mĂłdszereinek tanulmányozása : kávĂ©pĂłtlĂł-fĹ‘zetek szĂnĂ©nek kvantitatĂv meghatározása
SzerzĹ‘ a kávĂ©pĂłtlĂł-fĹ‘zetek szĂnĂ©nek meghatározására a sĂşly szerint bemĂ©rendĹ‘ ultramarin por helyett az ugyancsak szĂnkompenzáciĂłn alapulĂł, de metilenkĂ©k mĂ©rĹ‘oldattal törtĂ©nĹ‘ tĂ©rfogatos elemzĂ©si m Ăłdszert ajánlja. A kemĂ©ny cukorkák savtartalm ának meghatározásánál az aktĂv szĂ©nnel valĂł derĂtĂ©s nemcsak fölösleges, hanem helytelen is, m ert a szĂ©n pufferhatás következtĂ©ben savat fogyaszt Ă©s a meghatározásnál tĂşl kicsiny Ă©rtĂ©ket kapunk. A cukorkaoldatok fenolftalein indikátor mellett közvetlenĂĽl is m egtitrálhatĂłk. A m ustár ecetsavtartalmának meghatározása a rendkĂvĂĽl nehĂ©zkes vĂzgĹ‘zdesztillálás helyett lumineszcenc indikátor (lucigenin) jelenlĂ©tĂ©ben közvetlenĂĽl vĂ©gezhetĹ‘. Verfasser empfiehlt zur Bestimmung des Farbtones von Ersatzkaffee-AufgĂĽssen anstatt der vorgeschriebenen Methode vermittels einzuwägenden Ultramarinpulvers ein ebenfalls auf Farbkompensation gegrĂĽndetes, jedoch mit einer Messlösung von Methylenblau ausfĂĽhrbares, titrimetrisehes Verfahren. Bei der Bestimmung des Säuregehaltes von Drops ist die Klärung mit Tierkohle nicht nur ĂĽberflĂĽssig, sondern fĂĽhrt sogar zu falschen Resultaten, da die Kohle durch Pufferwirkung Säure bindet und infolgedessen zu niedrige W erte erhalten werden. Die Zuckerlösungen kann man bei Verwendung des Indikators Phenolphtalein auch unm ittelbar titrieren. Die Bestimmung des Essigsäuregehaltes von Senf kann statt der sehr schwerfälligen Wasserdampfdestillation in Gegenwart eines luminescenten Indikators (Lucigenin) unmittelbar durchgefĂĽhrt werden. The author proposes for the determination of the colour of extracts prepared from coffee surrogates -in place of pulverized ultram arine dosed by weight- a volumetric method by a standard solution of m ethyleneblue, based also on colour compensation. At the determination of the acid content of hard sweets the clarification by active carbon is not necessary and yields low values since active carbon consumes some acid, due to its buffer action. Solutions prepared from sweets may directly be titrated in the presence of phenolpthalein as indicator. The determination of the content of acetic acid in m ustard m ay be carried o u t — in stead of th e ra th e r cum bersom e steam d estin atio n — by direct titration in the presence of a luminescent indicator (as lucigenine). Pour dĂ©terminer la couleur de la dĂ©coction des produits remplacant le cafĂ©, l'auteur propose, au lieu de peser gravimetriquement la poudre d'outrĂ©mer, la mĂ©thode volumetrique avec la solution standard de mĂ©thylĂ©nebleu, laquelle mĂ©thode est aussi fondĂ©e sur la compensation des couleurs. Pour dĂ©terminer la teneur en acid dans les sucres durs, la clarification avec le eharbon actif n'est pas seulement inutile mais aussi incorrecte, parceque le eharbon, ä cause de l'effet tam pon consomme de l'acide et on re^oit des rĂ©su ltats tro p bas. On p e u t doser les solutions de sucres directement avec l'indicateur de phĂ©nolphtaleine. Au lieu de la mĂ©thode trĂ©s compliquĂ©e avec la distillation par la vapeur d'eau, on peut dĂ©terminer la teneur en acide acĂ©tique dans les moutardes par dosage direct en prĂ©sence d'un indicateur lumineux (lucigenin)
Resolving The Moth at Millimeter Wavelengths
HD 61005, also known as "The Moth," is one of only a handful of debris disks
that exhibit swept-back "wings" thought to be caused by interaction with the
ambient interstellar medium (ISM). We present 1.3 mm Submillimeter Array (SMA)
observations of the debris disk around HD 61005 at a spatial resolution of 1.9
arcsec that resolve the emission from large grains for the first time. The disk
exhibits a double-peaked morphology at millimeter wavelengths, consistent with
an optically thin ring viewed close to edge-on. To investigate the disk
structure and the properties of the dust grains we simultaneously model the
spatially resolved 1.3 mm visibilities and the unresolved spectral energy
distribution. The temperatures indicated by the SED are consistent with
expected temperatures for grains close to the blowout size located at radii
commensurate with the millimeter and scattered light data. We also perform a
visibility-domain analysis of the spatial distribution of millimeter-wavelength
flux, incorporating constraints on the disk geometry from scattered light
imaging, and find suggestive evidence of wavelength-dependent structure. The
millimeter-wavelength emission apparently originates predominantly from the
thin ring component rather than tracing the "wings" observed in scattered
light. The implied segregation of large dust grains in the ring is consistent
with an ISM-driven origin for the scattered light wings.Comment: 10 pages, 6 figure
Descriptive study of oral health, dental care and health behavior of inpatients undergoing physical medicine and rehabilitation
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