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Abstract  

Isomalt, a commercial sugar alcohol widely used as a sweetener, is approximately a 1:1 mixture of two diastereomers, -D-glucopyranosyl-1-6-mannitol (GPM) and -D-glucopyranosyl-1-6-sorbitol (GPS). A calorimetric investigation has been carried out on mixtures of isomalt with GPS, in the (molar) composition range 0.45<x GPS<1, for both crystalline and amorphous states.The GPS-rich portion of the solid-liquid GPM/GPS phase diagram was established and discussed in light of the existing literature. New evidence was given for the non-ideality of GPM/GPS mixtures, by indicating excess interactions in the melt and/or in the solid state. The commonly accepted hypothesis of a simple GPM/GPS eutectic forming isomalt was refuted in favour of more complicated mixture behaviour with possible formation of a complex.Glass transition and physical ageing of isomalt and GPS were re-visited, with peculiar attention given to the measurement conditions. Standard thermal histories were adapted to each sample and the fictive temperature was used for the characterisation of the structural glass states. A linear increase of the fictive temperature was found upon passing from pure GPS to x GPS=0.45. GPS showed a slightly higher enthalpy relaxation rate than isomalt.

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Abstract  

A DSC study has been carried out on isomalt, a commercial sugar alcohol derived from sucrose and widely used as a sweetener in the food industry. Isomalt is a mixture of two isomers:α-D-glucopyranosyl–1-6-mannitol (GPM) and α-D-glucopyranosyl–1-6-sorbitol (GPS). Release of the water of crystallisation (around 100C)and melting (around 150C) have been phenomenologically characterised using different scanning rates and heat treatments. The effect of dehydration/re-hydration on the melting has been investigated. The isomalt glass transition, at about 60C, was studied on samples cooled after melting. The dynamic aspect of structural relaxation of isomalt has been quantified by its fragility parameter. Glassy state stability has been evaluated by performing ageing experiments at sub-T g temperatures. During ageing, apart from the expected enthalpy relaxation effects, isomalt showed a peculiar behaviour, due to its isomeric composition. These preliminary and phenomenological results have been interpreted in terms of isomer structure and of carbohydrate-water interactions in the mixture.

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Summary  

It has been observed that among the seven municipalities of the Island of Krk the three in the central part of the island have increased disease incidence rates for the five groups of diseases: (a) neoplasm, (b) diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism, (c) endocrine, nutritional and metabolic diseases, (d) mental and behavioral disorders and (e) diseases of the circulatory system. One of the etiological factors is assumed to be the influence of the geochemical environment. The average element concentration values of six trace elements (Mn, Fe, Ni, Cu, Zn and As) for the geochemical environment in the individual municipalities were determined by XRF analyses of soil, plant, potable water and hair samples. The data on disease incidence rates for the individual municipalities, from 1997 to 2001, have been obtained from the Public Health Institution in charge of monitoring population health on the island. Diseases' groups have been defined by the WHO methodology. The GPS-GIS methodology was used to obtain maps of trace elements in different matrices and disease incidence distributions. Data analyses were performed by multivariate statistical methods (principal component analysis and cluster analysis). It has been shown that the concentration levels of the elements could be related to disease incidence rates.

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Abstract  

Using gamma-spectrometry systems on mobile units with accurate position information is a convenient means for surveying large areas for radioactive fallout or finding hot spots due to misplaced sources or releases from nuclear installations. Traditionally, large (tens of litres) high efficiency NaI(T1) detectors have been used for the purpose. HPGe detectors, however, offer certain advantages which can often compensate for their lower efficiency. This kind of remote sensing, regardless of detector type, requires specialized software. In order to provide accurate position information, the integration times must be kept as short as possible. This is especially true for fast air-borne measurements where counting periods below one second are desirable. We have constructed a special version of SAMPO software which controls data acquisition and runs real-time gamma-spectrum analysis including peak determination, nuclide identification, activity calculations, and reporting. The measurement/analysis cycle can be reduced down to 0.5 seconds on a standard Pentium-based PC. The analysis results are combined with accurate co-ordinates from a differential GPS system on a color coded map. The system is also able to give alarms based on different criteria. We have already measured and analyzed more than 500 000 spectra in field applications using jets, helicopters, cars, and also on-foot.

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of the university flat roof (GPS Loc: 50°39′58.829″N, 14°1′54.659″E, Altitude: 195 m a.s.l.) regularly at 2 p.m. (CET), on days when sky was empirically assessed as “clear and bright”. These records are shown in Fig. 2 . Despite data fluctuation, the

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Journal of Thermal Analysis and Calorimetry
Authors:
C. A. Gracia-Fernández
,
P. Davies
,
S. Gómez-Barreiro
,
Beceiro J. López
,
J. Tarrío-Saavedra
, and
R. Artiaga

. Cassettari , M , Papucci , F , Salvetti , G , Tombari , E , Veronesi , S , Johari , GPS 1993 Simultaneous measurements of enthalpy and heat capacity of a thermosetting polymer during the curing process . Rev Sci Instrum 64 : 1076 – 1080 10

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Progress in Agricultural Engineering Sciences
Authors:
Miklós Neményi
,
Attila J. Kovács
,
Judit Oláh
,
József Popp
,
Edina Erdei
,
Endre Harsányi
,
Bálint Ambrus
,
Gergely Teschner
, and
Anikó Nyéki

acquisition of tractors and other agricultural machines and devices, and robots (UGVs: Unmanned Ground Vehicles) with accurate positioning (GPS, RTK: Real Time Kinematic, Lidar). The WSN (Wireless Sensor Network) is a wireless network of spatially distributed

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Talajnedvesség-tartalom mérése földradarral (GPR) és mezőgazdasági alkalmazhatóságának lehetőségei

Soil water content measurements with ground penetrating radar (GPR) and its application possibilities in the agriculture

Agrokémia és Talajtan
Authors:
András Herceg
and
Csaba Tóth

tesz a GPS-rendszerekkel való plug-and-play kapcsolat segítségével. A közelmúltban kereskedelmi forgalomba került műholdas kommunikációs jelvétel alapú GPS rendszer az „European Geostationary Navigation Overlay Service” (EGNOS) és a „Wide Area

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Húsz éves avarmanipulációs kísérlet hatásai barna erdőtalaj szén tartalmára és vízkapacitására: Síkfőkút DIRT Project

The effects of a twenty-year litter manipulation experiment on the carbon content and water retention capacity of the examined Luvisols: Síkfőkút DIRT Project

Agrokémia és Talajtan
Authors:
István Fekete
,
Áron Béni
,
Katalin Juhos
, and
Zsolt Kotroczó

. Kutatásaink során ezekre az eltérésekre is igyekeztünk választ találni. Anyag és módszer A Síkfőkút Project 27 hektáros területe a Bükk hegység déli részén 325 méteres átlag magasságban helyezkedik el. GPS-es koordinátái é.sz. 47,9268°; k.h. 20,4433° ( 1. ábra

Open access

conditions for the digital paradigm shift is precision farming. The application of the GPS (Global Positioning System) navigation system in the first half of 1990 laid the foundations of precision farming, which represents a revolutionary change from an

Open access