Search Results

You are looking at 1 - 10 of 206 items for :

  • "structural characteristics" x
  • Refine by Access: All Content x
Clear All

Introduction The “structural characteristics” of electronic gambling machines (EGMs) are design features that can promote spending excessive time and money on these games, which can therefore contribute to gambling

Open access

/technological citations that may serve as a foundation to understand the organization of knowledge. Structural characteristics of citation networks The first feature observed in citation networks is their small-world network structure, which is

Restricted access
Journal of Behavioral Addictions
Authors:
Rune A. Mentzoni
,
Jon Christian Laberg
,
Geir Scott Brunborg
,
Helge Molde
, and
Ståle Pallesen

M. Walker K. Shannon M.-J. Coughlan 2005 Structural characteristics of electronic gaming

Open access

In this work the thermal characteristics of cellulose samples with different structure were investigated. The samples were prepared by reacting the cellulose with ethanolic hydroxide solution. Depending on the time of alkaline treatment, the intensity of cellulose transformation differed. Starting from cellulose I structure, with the highest degree of crystallinity, the other samples consisted of mixed structures of cellulose I and II, or were completely transformed to cellulose II structure with the lowest degree of crystallinity. The thermal behaviour of the samples was studied by using a Perkin Elmer TGS-2 and DSC-2 instruments. The kinetic parameters of dehydration and degradation were determined from non-isothermal TG-data (Nitrogen-inert atmosphere and a heating rate of 20 deg/min). The thermal effects of water evolution (heating rate of 80 deg/min) of the cellulose samples were found to depend on the structural characteristics and the crystallinity of the samples. The activation energy and frequency factor were in correlation with the structural changes.

Restricted access
Journal of Behavioral Addictions
Authors:
Rune A. Mentzoni
,
Jon Christian Laberg
,
Geir Scott Brunborg
,
Helge Molde
, and
Ståle Pallesen

M-J Coughlan 2005 Structural characteristics of electronic gaming machines and satisfaction of play among recreational and problem gamblers International Gambling Studies

Open access

Abstract  

Tin oxide was supported on alumina, titania, magnesia and silica, treated with hydrogen at different temperatures and characterized by Mössbauer spectroscopy and X-ray diffraction. For the samples calcined at 773 K, tin is present as SnO2 on alumina, magnesia and silica, but it occupies Ti sites on titania. After hydrogen treatment at high temperatures, tin is reduced from Sn(IV) to Sn(II) on alumina and titania, from Sn(IV) to Sn(0) on silica, but practically not reduced on magnesia. These results show the different degree of interaction between tin and the supporting material.

Restricted access

Abstract

Organobentonites were synthesized by treating Na-bentonites (Wyoming and Reşadiye) with cetylpyridinium chloride (CPC) using ion exchange method. The difference in the basal spacing by 0.65 Å and a higher mass loss by 13.32% of organobentonite (Wyoming) in the temperature range 200–550°C comparing with that of organobentonite (Reşadiye) were in conformity with the CEC values of organobentonites. The HOH stretching and bending peaks of bentonites became sharper following the treatment with the organo-cation. The intensity decrease of the Al–OH band for organobentonite (Reşadiye) and in particular, the significantly higher amount of m-cresol retained by the organobentonite of lower CEC than that by the organobentonite (Wyoming) indicate the influence of the CP cation on the adsorption process.

Restricted access

Abstract  

Two sets of hardened cement pastes were prepared by (a) impregnation with polymethyl methacrylate and polystyrene or (b) admixing with water-soluble condensates(superplasticizers) such as Na-phenol sulphonate formaldehyde, Na-polystyrene sulphonateand Na-β-naphthol sulphonate formaldehyde. The pastes were hydrated for 180 days. The results of nitrogen adsorption indicated that polymer impregnation strongly affected the specific surface areas and the total pore volumes of the hardened cement pastes. XRD analysis, DTA and TG demonstrated (a) the formation of new phases as a result of the interactions involving the polymer within the pore system of the hydrated products of the impregnated cement pastes, and (b) no change in the phase composition of the hydrated products of the cement pastes admixed with superplasticizers.

Restricted access

Chañar (Geoffroea decorticans- Fabaceae) is a tree from South America that is normally infected with galls originated by insects. One of its parasites is Allodiplosis crassa (Cecidomyiidae, Diptera) which produces globular galls with sticky prolongations. Since this plant has medicinal uses in Argentina, its infestation could alter the quality of the plant drug. The surface of insect-induced galls usually contains defensive features such as trichomes, increased hardness and an increase in the content of polyphenolic compounds. The objective of this research is to assess the structural and histochemical features of the gall and to compare the content of polyphenolic metabolites in the gall, in the healthy leaf and in lignified stems of G. decorticans. The methanolic extract from the galls showed the highest amount of polyphenolic and proanthocyanidins and the lowest amount of hydroxycinnamic derivatives and flavonoids compared to the methanolic extract of the leaves. The photographs taken from the external surface of the gall showed that some prolongations have heads. The histochemical analysis showed that the prolongations have a high amount of proanthocyanidins and flavonoids; and that the heads are reactive to Sudan III. These phytochemical and histological characteristics may have a defensive role against harmful fungi and parasites that attack the larvae of the A. crassa. The results of this study show the presence of defensive features in an insect-induced gall of a medicinal plant with potential implications in the pharmacological activity of this species. This is the first report of a histochemical and phytochemical study in G. corticans galls.

Restricted access

. Griffiths 2010 Video game structural characteristics: A new psychological taxonomy International Journal of Mental Health and Addiction 8 1 90

Open access