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Renewable Materials (renewable + material)
Selected AbstractsChemInform Abstract: Conversion of Fructose to 5-Hydroxymethylfurfural Using Ionic Liquids Prepared from Renewable Materials.CHEMINFORM, Issue 15 2009Suqin Hu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Colours and Metallic Sheen in Beetle Shells , A Biomimetic Search for Material Structuring Principles Causing Light Interference,ADVANCED ENGINEERING MATERIALS, Issue 4 2008T. Lenau Abstract Visual aesthetic has always played a vital role for the success of many products. This includes colours and glossiness and metal appearance which is often achieved using surface coatings. Present coating techniques do, however, have limitations. It is difficult to reach very bright and brilliant colours, colours tend to fade over time and many of the materials and coating technologies pollute and have other environmental problems. Beetles in nature have many of the desired properties: They have appealing brilliant colours and some even with metallic appearance. It is noticeable that the colours are long lasting as some of the beetles we have studied at the zoological museum are more than 200 years old and have colours and brightness as if they were still alive. Furthermore, the beetles in nature are part of sustainable ecosystems, which means that they are made from renewable materials that are broken down and recycled when the beetle dies. Beetles also possess another and very attractive property: Their metallic look originates from structures in organic materials which is both electrically and thermal insulating. The industrial perspective is to be able to manufacture products with attractive metallic surfaces that do not feel so cold to touch as their metallic counterparts and that do not represent an electrical shock hazard. [source] Optimization of the reaction parameters of epoxidation of rapeseed oil with peracetic acidJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2010Eugeniusz Milchert Abstract BACKGROUND: The epoxidation of vegetable oils has been a subject of interest for many years; epoxidized oils are frequently used as plasticizers and as renewable materials for the manufacture of alcohols, glycols and many other complex compounds with excellent antioxidant and antifriction properties. In this work the epoxidation process of rapeseed oil (RO) with peracetic acid generated in situ by the reaction of 30 wt% hydrogen peroxide and acetic acid has been studied. Optimization studies were performed by application of a statistical experimental design method utilizing a rotatable-uniform design. RESULTS: The significant parameters for the RO epoxidation process were established as temperature, molar ratio of hydrogen peroxide to rapeseed oil, molar ratio of acetic acid to rapeseed oil and reaction time. The process description was based on five response functions: iodine number, epoxy number, conversion, yield and selectivity. The highest values of all functions with the exception of selectivity were achieved for the same values of parameters: temperature 65 °C, molar ratio of hydrogen peroxide to RO 11.1:1 mol mol,1, molar ratio of acetic acid to RO 1.89:1 mol mol,1 and reaction time 6 h. CONCLUSION: In summary, these optimum parameters allow one to obtain epoxidized rapeseed oil with a yield of 66.2 mol% at an oil conversion of 91.0 mol% in mild and relatively safe conditions. The epoxy number of the product was 0.207 mol per 100 g, whereas the iodine number was 0.027 mol per 100 g. Copyright © 2010 Society of Chemical Industry [source] Front and Back Covers, Volume 21, Number 4.ANTHROPOLOGY TODAY, Issue 4 2005August 200 Front and back cover caption, volume 21 issue 4 Front cover The photo on the front cover, taken from the World Monuments Fund (WMF) website, shows house in Hilinawalö Mazingö, South Nias, Indonesia which was recently included on the WMF's List of 100 most endangered sites. Built in the 19th century, the house withstood the massive earthquake of 28 March 2005 that reduced the port towns of Nias to rubble and made over 150,000 people homeless. Constructed without nails, its complex structure can absorb tremors where modern concrete houses collapse. However, the hardwoods needed to replace columns and panels damaged by fire, rain and insects are no longer available, since Nias has been stripped of primary forest. Urgent conservation work is needed if the stone-paved villages and traditional architecture of Nias are to survive further destruction. In order to house the homeless, reconstruction planners are now studying the possibility of reviving traditional designs using cheaper, renewable materials. South Nias, whose plight was barely reported in the aftermath of the earthquake, received no government attention until ten days after the disaster. In his article on pp. 5-7 of this issue, Andrew Beatty reflects on the lack of development in Nias since he began fieldwork there in 1986 and considers the context of the recovery operation, showing how selective reporting, narrowly focused on stereotypical human interest stories, has failed to address local conditions, allowing corruption and inefficiency to thrive. Local knowledge is key to the success of aid. But only better reporting of regional power structures and stakeholders, combined with greater scrutiny of official dealings, will help to ensure that aid reaches those most in need. Back cover POLICY AND RACE The back cover reproduces questions from recent censuses conducted in England and Wales (above) and the USA (below). The former asks the respondent to state 'your ethnic group'; the latter seeks information on a 'person's race'. Statistics from the responses to these questions are given on page 4 of this issue. The British census question on ethnic origin, first introduced in 1991, is unusual in the European context. The 2001 census introduced a new 'mixed' category, as well as the term 'British' as a qualifier (to permit identification as British Black or British Asian), and a 'white' category subdivided into British, Irish and others. It also included a question on religion for the first time in more than a century, in response to the concerns of those for whom ethnic affiliation relates closely to religion (e.g. South Asian Muslims). In the US, the census of 2000 offered individuals, for the first time, the opportunity to identify themselves as belonging to more than one racial category (previously people of mixed descent were asked to choose a single racial category or to respond as 'some other race'). Most countries conduct regular censuses of their populations. In 1995 the United Nations Assembly passed a resolution calling on all its member countries to compile census data by 2004. However, a census depends on the consent of the population. Germany has not taken a full census since 1987, after postponing its scheduled 1983 census because of public concern over the proposed use of census returns to update local population registers; the Netherlands has not had a census since 1971, when high rates of refusal rendered returns unreliable. In common with a number of other countries, including Denmark, these two have turned to alternative data sources, particularly population and housing registers as well as sample surveys, for population statistics. The discourse of governance and perceptions of social category are powerfully influenced by the terms officially sanctioned by governments for the classification of citizens. The US census identifies its use of race as 'sociopolitical constructs' that are not 'scientific or anthropological in nature' (quickfacts.census.gov/qfd/meta/long_68186.htm). Race is surely one of the most potent and elusive of concepts anthropology is trying to make sense of, whether as a scientific or as a cultural category. In this issue of AT, Michael Banton contends that contributors to recent debate have not distinguished sufficiently between scientific classifications and the categories current in the English language of everyday life. In their review of the recent 'Anthropology and Genomics' conference, Simpson and Konrad point out how issues of race and policy arise in this dynamic field. ANTHROPOLOGY TODAY continues to offer a forum for topical debate on issues of public concern, and welcomes further contributions on these questions. [source] Advanced biofuel production in microbesBIOTECHNOLOGY JOURNAL, Issue 2 2010Pamela P. Peralta-Yahya Abstract The cost-effective production of biofuels from renewable materials will begin to address energy security and climate change concerns. Ethanol, naturally produced by microorganisms, is currently the major biofuel in the transportation sector. However, its low energy content and incompatibility with existing fuel distribution and storage infrastructure limits its economic use in the future. Advanced biofuels, such as long chain alcohols and isoprenoid- and fatty acid-based biofuels, have physical properties that more closely resemble petroleum-derived fuels, and as such are an attractive alternative for the future supplementation or replacement of petroleum-derived fuels. Here, we review recent developments in the engineering of metabolic pathways for the production of known and potential advanced biofuels by microorganisms. We concentrate on the metabolic engineering of genetically tractable organisms such as Escherichia coli and Saccharomyces cerevisiae for the production of these advanced biofuels. [source] | ||||||||||