33 research outputs found

    Studies on the promotion of nickel—alumina coprecipitated catalysts: I. Titanium oxide

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    A series of TiO2-promoted nickel—alumina catalysts has been prepared and characterized. The promoter was added in various proportions to a calcined coprecipitated nickel—alumina material by adsorption of the acetylacetonate complex of titanium, followed by further calcination and reduction. The structure of the resultant materials was similar to that of the unpromoted coprecipitated nickel—alumina. The chemisorption properties of the catalyst and its behaviour in the CO/H2 reaction were characteristic of a strong metal-support interaction (SMSI) reported in the literature for Ni/TiO2. The strong adsorption of both carbon monoxide and hydrogen were suppressed while the activity for carbon monoxide hydrogenation was increased, the activation energy being lowered. The higher activity, however, was relatively unstable under reaction conditions

    Effects of forest conversions to oil palm plantations on freshwater macroinvertebrates: a case study from Sarawak, Malaysia

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    Oil palm plantations in Malaysia are expanding rapidly due to global oil and biofuel demand. This is of particular concern, as the conversion process of forested land to oil palm plantations and the maintenance of a plantation can significantly alter freshwater ecosystems. This is a result of the initial loss of a forested catchment, particularly the riparian vegetation, changes to the bed and banks of streams, sedimentation and changes to detrital inputs. In addition, various chemicals used on the plantations leach into the nearest waterways and can potentially affect freshwater macroinvertebrates. In the Malaysian region, these are largely endemic and generally incompletely known. This study assesses the impact of oil palm plantations on stream macroinvertebrates by comparing four steams flowing through undisturbed rainforest and four streams flowing through oil palm plantations in Sarawak, Malaysia. Freshwater macroinvertebrates were sampled using the standard three-minute kick sample method with accompanying chemical measurements. Although there were no distinct differences between the control and oil palm streams in the chemical data, the invertebrate communities provided a different interpretation of stream quality. Invertebrates were more abundant, species rich and diverse in rainforest streams than in oil palm ones. Most noticeably, two whole orders of insecta, Coleoptera (beetles) and Hemiptera (true bugs), were absent from the oil palm streams. This may be the result of the disappearance of natural bank habitats, the sensitivity to the pesticides targeted at the Rhinocerous beetle (Oryctes rhinoceros), or a combination of both

    The adaptation of self-report measures to the needs of people with intellectual disabilities : a systematic review

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    Persons with intellectual disabilities (ID) may have difficulties providing reliable and valid accounts of their personal experiences through self-report measures. The aim of the current study was to systematically review the peer-reviewed research literature on the adaptations needed to develop “ID-inclusive” self-report measures. A search of APA PsycInfo, PubMed, Web of Science, and Google Scholar identified 49 studies that met inclusion criteria. A GRADE-CERQual assessment was performed to determine the level of confidence in the review findings. One hundred sixty-one recommendations for the development of “ID-inclusive” self-report measures were extracted from 49 included studies. Recommendations were presented in a GRADE-CERQual Summary of Findings table, according to a five-stage model of instrument development. This review offers much-needed practical guidance for clinicians and researchers on how to develop “ID-inclusive” self-report measures. Recommendations for future research about self-report instrument development for use with people with ID are presented
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