Search results for "elemental"

EDXRF and TXRF analysis of elemental size distributions and environmental mobility of airborne particles in the city of Riga, Latvia

2004

Airborne particles were investigated in the central part of Riga during October 2000. Mass, black carbon and elemental concentrations of airborne particles were measured on Teflon filters from a dichotomous impactor, which samples fine (<2.5 µm) and coarse (2.5‐10 µm) fractions of particles. In order to obtain more detailed information on the size distributions of different elements, a seven-stage Batelle cascade impactor was used, in which quartz plates treated with silicone grease were utilized as backing for the different stages. Total reflection x-ray fluorescence (TXRF) and energy-dispersive x-ray fluorescence (EDXRF) spectrometry were used for elemental analysis on the quartz plates a…

Syntheses, Structures and Reactivity of New Intramolecularly Coordinated Tin Alkoxides Based on an Enantiopure Ephedrine Derivative

2011

The syntheses of the tin compounds [LSn]2 (2), spiro-L2Sn (3), [LSnW(CO)5]2 (4), [LSnBr2]2 (5), spiro-L2Sn·SnBr4 (6) and LSn[OC(O)Ph]2 (8), where L = MeN(CH2CMe2O)[(S)-CH(Me)-(R)-CH(Ph)O], and (Ph4P)2SnBr6 (7) are reported. The compounds were characterized by elemental analysis, multinuclear NMR spectroscopy including 119Sn cross polarisation–magic angle spinning NMR (CP–MAS) (2, 3–6), electrospray ionization mass spectrometry (2–4) and single crystal X-ray diffraction analysis (2, 2·C7H8, 3a, 3b, 4·C7H8, 5, 6·C7H8, 7).

Synthesis and characterization of diatomaceous earth chemically modified with γ-aminopropyltrimethoxysilane

2003

A stationary phase for thin-layer chromatography has been prepared by bonding purified diatomaceous earth (rich in silica) with γ-aminopropyltrimethoxysilane. The phase has been characterized by elemental analysis, measurement of the specific surface area, IR spectroscopy, thermal analysis, and chromatographic testing.

Synthesis and characterization of alumina R chemically modified withn-octyl for use as a stationary phase in TLC

2003

A stationary phase for thin-layer chromatography has been prepared by attaching 1-octene to alumina R. This stationary phase has been characterized by elemental analysis, measurement of specific surface area, IR spectroscopy, and by chromatographic testing.

Provenance of Early Bronze Age Metal Artefacts in Western Switzerland Using Elemental and Lead Isotopic Compositions

2011

Parenterale Ernährung in der Behandlung des Minderwuchses bei Adoleszenten mit Morbus Crohn

1992

Growth retardation and delayed puberty occur in 20-35% of children and adolescents with Crohn's disease. Alternate day corticosteroid treatment, use of azathioprine, enteral or parenteral hyperalimentation and surgery have been advocated to reverse growth failure. Because of nonacceptance of elemental diet 7 patients with Crohn's disease and growth retardation received parenteral nutrition for 2-3 months (maximal for more than 30 months in one patient). All of them exhibited a mean weight gain of 10 kg and a mean increase of their height velocity from 2.4 to 7.1 cm/year. Main problems were bacterial infections and dislocations of the central lines. Surgery was performed in 3 adolescents imm…

Indoor air quality in schools of a highly polluted south Mediterranean area

2019

This study aimed at surveying lower secondary schools in southern Italy, in a highly polluted area. A community close to an industrial area and three villages in rural areas was investigated. Indoor temperature, relative humidity (RH), gaseous pollutants (CO 2 and NO 2 ), selected biological pollutants in indoor dust, and the indoor/outdoor mass concentration and elemental composition of PM 2.5 were ascertained. Temperature and RH were within, or close to, the comfort range, while CO 2 frequently exceeded the threshold of 1000 ppm, indicating inadequate air exchange rate. In all the classrooms, median NO 2 levels were above the WHO threshold value. Dermatophagoides p. allergen concentration…

Gas-chromatographic elemental analysis via di(trifluorethyl)dithiocarbamato-chelates

1986

The capillary-gas-chromatographic conditions for the determination of trace metals after extraction from aqueous solution are optimized by coupling of capillaries and improvement of injection technique. Different detectors (FID and ECD) are tested. pH range and buffer systems for extraction of metal chelates are discussed.

Energy dispersive X-ray diffraction potentiality in the field of cultural heritage: simultaneous structural and elemental analysis of various artefac…

2007

The applicability of an Energy Dispersive X-ray Diffractometer to some technical questions in the field of Cultural Heritage is presented. This diffractometer, equipped with a white source, has been utilized for the structural and elemental analysis of some items having different nature. Given its design, the instrument allows to collect data from samples as big as a book or a little more. Samples, without collection of any portion and without any preliminary preparation, have been placed in the instrument and spectra have been collected in a wide energy range that contains X-ray fluorescence and diffraction features. In all cases, data acquired in air and in a non destructive way were reli…

ENERGY DISPERSIVE X-RAY DIFFRACTION IN CULTURAL HERITAGE SCIENCE: THE WINNING DUO OF STRUCTURAL AND ELEMENTAL ANALYSIS

2013

The capabilities of Energy-Dispersive X-ray Diffraction (EDXD) in the field of Cultural Heritage are disccussed. EDXD diffractometer, equipped with a white source, is particularly suited for the structural and elemental analysis of items having different nature. Given its compact and versatile design, the instrument allows to collect data from samples without tearing down of any portion and with no specific preparation. In the wide energy range sampled during the measurements, both X-ray fluorescence and diffraction features appear. In all cases, data are acquired in air and in a non-destructive way, and their collection is fast.