Search results for " Resource"
showing 10 items of 3405 documents
Introduction to Government and Disaster Resilience Minitrack
2017
Stakeholders' Perceptions about Fire Impacts on Lithuanian Protected Areas
2014
The aim of this work is to study Lithuanian stakeholders' perceptions of fire impacts in protected areas. For this study, the stakeholders consisted of foresters, ecologists and farmers. A clear understanding of the opinions of stakeholders about fire effects on environmental, social and economic aspects of Lithuanian protected areas will allow an assessment of the stakeholders' reaction to fire policy, including government measures towards fire prevention, suppression and application of prescribed fire to landscape management. The results showed that stakeholders in general think that fire is not a threat to Lithuania and to the ecological processes in the protected areas. However, they ag…
NATURALLY AVAILABLE SOLUTIONS FOR BUILDING NEW METABOLIC TERRITORIES
2021
Building new metabolic territories is a proactive way of responding to the challenges and precariousness of the contemporary city. Byintegrating solutions inspired by new scientific advances in urban ecology, cities are able to address some of the environmental threats. Many European cities are implementing alternative nature-based solutions to protect their health and tackle water scarcity, land consumption and climate change, to increase citizens' well-being. Wellbeing and health (Agenda 2030) are the most important analytical parameters for measuring the results and impacts of environmental project actions. With this in mind, the study presents a "nature-action" project hypothesis for wh…
Xylochemistry--Making Natural Products Entirely from Wood.
2015
The first total synthesis of the dimeric berberine alkaloid ilicifoline (ilicifoline B) is reported. Its carbon skeleton is constructed from ferulic acid, veratrole, and methanol. The synthesis reported herein employs starting materials solely derived from wood. The natural product is thus constructed entirely from renewable resources. The same strategy is applied to a formal total synthesis of morphinan alkaloids. The use of wood-derived building blocks (xylochemicals) instead of the conventional petrochemicals represents a sustainable alternative to classical synthetic approaches.
Activity of a Heterogeneous Catalyst in Deep Eutectic Solvents: The Case of Carbohydrate Conversion into 5-Hydroxymethylfurfural
2019
Obtaining industrially relevant products from renewable resources and developing processes under the light of sustainable chemistry is a prominent endeavor of present-day chemical research. In this context, herein we investigated the dehydration of fructose and sucrose in deep eutectic solvents promoted by the ion-exchange resin Amberlyst 15 as heterogeneous catalyst. We optimized the reaction conditions in terms of temperature, catalyst loading, and initial amount of substrate. Then, we looked at the effect of structural variations in the solvent components on the reaction outcome. Under the best experimental conditions, we obtained very good yields of 78% at 60 °C and 69% at 80 °C for fru…
Undecylenic acid: A tunable bio-based synthon for materials applications
2016
International audience; An undecylenic acid-based monoglyceride prepared from glycidol and undecylenic acid is used as suitable and tunable synthon for polymerization applications. Epoxidation and acrylation reactions lead to photopolymerizable monomers while transesterification with dimethyl carbonate, metathesis and aminolysis reactions provide access to polyhydroxyurethane-based materials. The successive intermediates were synthesized according to a green chemistry approach implicating solvent-less and catalyzed reactions, and were at each step fully characterized by infrared, 1H and 13C{1H} NMR spectroscopy, elemental analysis and mass spectrometry. Analyses of the resulting polymer mat…
Examples of xylochemistry: colorants and polymers
2017
Against the backdrop of modern sustainable chemistry and valorization of biomass for chemical raw materials, the syntheses of indigo dyes and polyamides as representatives of two classes of everyday chemical products based on xylochemicals are described. Wood-derived starting materials were transformed into functional materials using the principles of green chemistry to expand the scope of products gained from renewable resources. The indigo dyes were synthesized in a short, straightforward sequence starting from vanillin. Two polyamides, representatives of an important class of polymers, were obtained from 4-propylcyclohexanol, which is one of the longest known (and most abundant) hydrogen…
Landfill gas upgrading with countercurrent water wash.
2006
A pilot-scale countercurrent absorption process for upgrading landfill gas to produce vehicle fuel was studied using absorption and desorption units and water as absorbent. The height-to-diameter ratio of the absorption column used was 3:1 instead of the more conventionally used 20:1 ratio, and a higher pressure was used along with a lower water flow rate. The effects of pressure (10-30 bar) and water and gas flow-ratios on the upgrading process were studied. Methane content in the product gas increased to near or above 90% with both gas flows (50 and 100 l/min) used at over 20 bar pressure with 10 l/min water flow and at 30 bar pressure with 5l/min water flow. Carbon dioxide content with t…
Mechanically-biologically treated municipal solid waste as a support medium for microbial methane oxidation to mitigate landfill greenhouse emissions.
2005
The residual fraction of mechanically-biologically treated municipal solid waste (MBT residual) was studied in the laboratory to evaluate its suitability and environmental compatibility as a support medium in methane (CH(4)) oxidative biocovers for the mitigation of greenhouse gas emissions from landfills. Two MBT residuals with 5 and 12 months total (aerobic) biological stabilisation times were used in the study. MBT residual appeared to be a favourable medium for CH(4) oxidation as indicated by its area-based CH(4) oxidation rates (12.2-82.3 g CH(4) m(-2) d(-1) at 2-25 degrees C; determined in CH(4)-sparged columns). The CH(4) oxidation potential (determined in batch assays) of the MBT re…
Road project opportunity costs subject to a regional constraint on greenhouse gas emissions
2012
Abstract France has constrained the Aquitaine region to set up a climate plan to avoid an emission of 2883 ktCO 2 eq for the period 2007–2013. In parallel, the region has decided to carry out the construction of road infrastructures in order to avoid very high congestion costs. Those road projects will involve an increase in greenhouse gas (GHG) emissions during that period. In the present context of strong sustainability, all emissions (direct and indirect) generated by those projects should be offset. At the regional level, the offsetting of GHG emissions is usually carried out by implementing carbon sequestration projects or projects that reduce energy demand. This paper aims at determin…