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Few Samples (few + sample)
Selected AbstractsHigh-Si phengite, mineral chemistry and P,T evolution of ultra-high-pressure eclogites and calc-silicates from the Dabie Shan, eastern ChinaGEOLOGICAL JOURNAL, Issue 3-4 2000Robert Schmid Abstract A suite of coesite,eclogites and associated calc-silicate rocks from the ultra-high-pressure (UHP) belt in the Dabie Shan (eastern China) was investigated petrologically. Field relations and the presence of UHP minerals such as coesite, omphacite and high-Si phengite in the eclogites and the enclosing calc-silicates testify to a common metamorphic evolution for these two lithologies. Except for one sample, all bear phengite with unusually high silica contents (Si up to 3.7 per formula unit). Phengite occupies various textural positions indicating that different metamorphic stages are reflected by these white micas, which correlate with distinct mineral zonation patterns. Using the latest thermobarometric calibrations for eclogite-facies rocks, maximum pressure,temperature (P,T) conditions of 40,48 kbar at <,750°C were estimated for the peak-metamorphic mineral assemblages. These P,T conditions were calculated for both eclogitic garnet porphyroblasts with diffusion-controlled zoning as well as garnet porphyroblasts with prograde growth zonation patterns. Most samples were affected by a strong retrograde overprint mainly under eclogite- and amphibolite-facies conditions. Thermobarometry using mineral sets from different textural positions reveals cooling and decompression of the UHP rocks down to <,20 kbar at <,600°C for the bulk of the samples. Decompression and heating indicated by a few samples is interpreted to result from mineral chemical disequilibrium or late thermal influence. These new data show that subduction of continental crust in the Dabie Shan was deeper than previously thought, and also that some cooling and decompression took place at upper-mantle depths. Copyright © 2000 John Wiley & Sons, Ltd. [source] A LEXICON FOR FLAVOR DESCRIPTIVE ANALYSIS OF GREEN TEAJOURNAL OF SENSORY STUDIES, Issue 3 2007JEEHYUN LEE ABSTRACT A lexicon for describing green tea was developed using descriptive analysis methods. A highly trained, descriptive sensory panel identified, defined and referenced 31 flavor attributes for green tea. One-hundred and thirty-eight green tea samples from nine countries , China, India, Japan, Kenya, Korea, Sri Lanka, Taiwan, Tanzania and Vietnam , were selected to represent a wide range of green teas. Attributes could be categorized as "Green" (asparagus, beany, Brussels sprout, celery, parsley, spinach, green beans, green herb-like); "Brown" (ashy/sooty, brown spice, burnt/scorched, nutty, tobacco); "Fruity/Floral" (fruity, floral/perfumy, citrus, fermented); "Mouthfeel" (astringent, tooth-etching); "Basic Tastes" (overall sweet, bitter); and other attributes (almond, animalic, grain, musty/new leather, mint, seaweed, straw-like). Some attributes, such as green, brown, bitter, astringent and tooth-etching, were found in most samples, but many attributes were found in only a few samples. Green tea processors, food industry, researchers and consumers will benefit from this lexicon with precise definitions and references that reliably differentiate and characterize the sensory attributes of green teas. PRACTICAL APPLICATIONS Green tea (and white tea) processors, food industrialists, researchers and consumers will benefit from this lexicon with precise definitions and references that reliably differentiate and characterize the sensory attributes of green tea. [source] Genetic distinctness and phylogenetic relationships among Undaria species (Laminariales, Phaeophyceae) based on mitochondrial cox3 gene sequencesPHYCOLOGICAL RESEARCH, Issue 4 2007Shinya Uwai SUMMARY Genetic relationships among Undaria species and among populations of each species were studied based on DNA sequences of the mitochondrial cox3 gene. Although three Undaria species, U. peterseniana (Kjellman) Okamura, U. pinnatifida (Harvey) Suringar and U. undarioides (Yendo) Okamura, have been described based mostly on blade morphology, plants with intermediate morphologies have also been found. Multiple plants from several populations in Japan were collected. Morphological characters could identify most of the samples unambiguously. A few samples with intermediate morphologies were also collected. Mitochondrial haplotypes found in each population were different for each identified species, and each species had multiple haplotypes. In the cox3 haplotype network analysis, the numbers of steps between haplotypes within and between species were similar, and haplotypes of each species did not group together. The close genetic relationships among species strongly suggest that these species are conspecific. Alternatively, recent speciation could be possible with maintenance of ancestral polymorphisms within the species (i.e. incomplete lineage sorting). Haplotypes of samples with intermediate morphologies were different for each sample and the same as ones found in the local population, suggesting interspecific hybridizations among species. [source] Determination of patterns of biologically relevant aldehydes in exhaled breath condensate of healthy subjects by liquid chromatography/atmospheric chemical ionization tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 7 2003Roberta Andreoli A method for the simultaneous determination of several classes of aldehydes in exhaled breath condensate (EBC) was developed using liquid chromatography/atmospheric pressure chemical ionization tandem mass spectrometry (LC/APCI-MS/MS). EBC is a biological matrix obtained by a relatively new, simple and noninvasive technique and provides an indirect assessment of pulmonary status. The measurement of aldehydes in EBC represents a biomarker of the effect of oxidative stress caused by smoke, disease, or strong oxidants like ozone. Malondialdehyde (MDA), acrolein, ,,, -unsaturated hydroxylated aldehydes [namely 4-hydroxyhexenal (4-HHE) and 4-hydroxynonenal (4-HNE)], and saturated aldehydes (n -hexanal, n -heptanal and n -nonanal) were measured in EBC after derivatization with 2,4-dinitrophenylhydrazine (DNPH). Atmospheric pressure chemical ionization of the analytes was obtained in positive-ion mode for MDA, and in negative-ion mode for acrolein, 4-HHE, 4-HNE, and saturated aldehydes. DNPH derivatives were separated on a C18 column using variable proportions of 20,mM aqueous acetic acid and methanol. Linearity was established over 4,5 orders of magnitude and limits of detection were in the 0.3,1.0 nM range. Intra-day and inter-day precision were in the 1.3,9.9% range for all the compounds. MDA, acrolein and n -alkanals were detectable in all EBC samples, whereas the highly reactive 4-HHE and 4-HNE were found in only a few samples. Statistically significant higher concentrations of MDA, acrolein and n -hexanal were found in EBC from smokers. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effect of water treatment on analyte and matrix ion yields in matrix-assisted time-of-flight secondary ion mass spectrometry: the case of insulin in and on hydroxycinnamic acidRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 21 2002Wilfried Szymczak A systematic study was performed to identify the origin of surprisingly high analyte-to-matrix yield ratios recently observed in time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis of oligo- and polypeptides mixed in matrices of ,-cyano-4-hydroxycinnamic acid (4HCCA). Several sets of samples of porcine insulin in 4HCCA (1:3100 molar) were prepared from liquid solutions by a nebuliser technique, with more than one order of magnitude variation in sprayed material (substrate silicon). Following different periods of storage in air and/or vacuum as well as exposure to high-purity water, TOF-SIMS analysis was performed under oblique impact of 22 keV SF5+. Treatment with water involved either deposition of a droplet covering the whole sample for times between 1 and 20,min or spraying with water in droplet equivalent quantities. The analyte and matrix molecules were detected as protonated molecules (insulin also in doubly protonated form). Even the as-prepared samples usually showed insulin-to-4HCCA yield ratios exceeding the molar ratio of the mixed material. Upon ageing in vacuum the matrix ion yields remained constant but the analyte yields decreased, partly due to break-up of intrachain disulfide bonds. Water treatment resulted in a pronounced decrease in the 4HCCA yield, typically by a factor of five, in parallel with an increase of the insulin yield, by up to a factor of four. Evidence is provided that these changes occur concurrently with a partial dissolution of 4HCCA at the sample surface. The enhanced insulin yield was not correlated with the Na+ yield. The typically 20-fold increase in the insulin-to-4HCCA yield ratio, generated by water exposure of the samples, provides the explanation for the high yield ratios observed previously with water-treated samples. Spraying with water or repeated exposure to water droplets caused a pronounced degradation of the insulin parent yields in combination with an increasing appearance of signals due to the B- and A-chains of insulin. To clarify the issue of surface segregation, a few samples were prepared by spraying acetone-diluted solutions of insulin on previously deposited layers of 4HCCA. Whereas the insulin yields from as-prepared samples were rather low, the yields observed after water treatment were comparable with those observed with samples of insulin in 4HCCA. The results suggest that a large amount of insulin is present at the surface of samples prepared from liquid mixtures of insulin in 4HCCA. With both methods of sample preparation, however, high secondary ion yields of insulin were only obtained after exposure of the samples to water. The chemical changes responsible for this beneficial effect still need to be identified. Copyright © 2002 John Wiley & Sons, Ltd. [source] Translations of the Bible into KaraimRELIGION COMPASS (ELECTRONIC), Issue 4 2009Henryk Jankowski The aim of this paper is to present the state of research on Bible translations into Karaite Turkic, which in Turkic studies is called Karaim. The term Bible is employed in its narrower meaning, which designates the Hebrew Bible or Old Testament. This article tries to show how the translators approached the original text and gives a few samples to demonstrate differences between several selected translations. [source] THE TECHNOLOGY OF PRODUCTION OF SASANIAN GLAZED POTTERY FROM VEH ARDA,?R (CENTRAL IRAQ)ARCHAEOMETRY, Issue 4 2008M. PACE Scanning electron microscopy coupled with an energy dispersive X-ray detector (SEM-EDS) has been used to study samples of Sasanian glazed pottery. Analysis of ceramic bodies revealed a general homogeneity in composition among the studied samples and the use of calcareous clay for their manufacture. Glazes are typically alkaline in composition, with sodium and potassium oxide contents between 8 and 13%, and between 3 and 5%, respectively; calcium and magnesium oxide contents are between 7 and 10%, and between 3 and 5%, respectively. These data suggest the use of plant ash together with a silica source for glaze production. Coating thickness is highly variable among different samples, from some 400 up to 1200 µm, but it is generally uniform when a single sample is concerned. Glazes are mostly coloured blue or blue-green; copper and iron are the colouring agents detected; abundance of bubbles, silicate crystals and relics of unmelted material are responsible for their generally opaque appearance, together with the presence of weathering products. The characteristics of the body to glaze contact zone, together with the widespread presence of bubbles, would not rule out production by a single firing process. A few samples feature a peculiar gritty coating on one side of their surface; SEM images show that they are actually partially vitrified, and EDS data denote a rather heterogeneous composition. It seems possible that they result from mixing clay together with the frit used for glaze development. [source] | |||||||||||||