485 resultados para carbon economy
Resumo:
As one of the largest sources of greenhouse gas (GHG) emissions, the building and construction sector is facing increasing pressure to reduce its life cycle GHG emissions. One central issue in striving towards reduced carbon emissions in the building and construction sector is to develop a practical and meaningful yardstick to assess and communicate GHG results through carbon labelling. The idea of carbon labelling schemes for building materials is to trigger a transition to a low carbon future by switching consumer-purchasing habits to low-carbon alternatives. As such, failing to change purchasing pattern and behaviour can be disastrous to carbon labelling schemes. One useful tool to assist customers to change their purchasing behaviour is benchmarking, which has been very commonly used in ecolabelling schemes. This paper analyses the definition and scope of benchmarking in the carbon labelling schemes for building materials. The benchmarking process has been examined within the context of carbon labelling. Four practical issues for the successful implementation of benchmarking, including the availability of benchmarks and databases, the usefulness of different types of benchmarks and the selection of labelling practices have also been clarified.
Resumo:
Greenhouse gas (GHG) emissions are simultaneously exhausting the world's supply of fossil fuels and threatening the global climate. In many developing countries, significant improvement in living standards in recent years due to the accelerating development of their economies has resulted in a disproportionate increase in household energy consumption. Therefore, a major reduction in household carbon emissions (HCEs) is essential if global carbon reduction targets are to be met. To do this, major Organisation for Economic Co-operation and Development (OECD) states have already implemented policies to alleviate the negative environmental effects of household behaviors and less carbon-intensive technologies are also proposed to promote energy efficiency and reduce carbon emissions. However, before any further remedial actions can be contemplated, though, it is important to fully understand the actual causes of such large HCEs and help researchers both gain deep insights into the development of the research domain and identify valuable research topics for future study. This paper reviews existing literature focusing on the domain of HCEs. This critical review provides a systematic understanding of current work in the field, describing the factors influencing HCEs under the themes of household income, household size, age, education level, location, gender and rebound effects. The main quantification methodologies of input–output models, life cycle assessment and emission coefficient methods are also presented, and the proposed measures to mitigate HCEs at the policy, technology and consumer levels. Finally, the limitations of work done to date and further research directions are identified for the benefit of future studies.
Resumo:
The influence of fluid flow, surface roughness and immersion time on the electrochemical behaviour of carbon steel in coal seam gas produced water under static and hydrodynamic conditions has been studied. The disc electrode surface morphology before and after the corrosion test was characterized using scanning electron microscopy (SEM). The corrosion product was examined using X-ray photoelectron spectroscopy (XPS) and X-ray diffractometry (XRD).The results show that the anodic current density increased with increasing surface roughness and consequently a decrease in corrosion surface resistance. Under dynamic flow conditions, the corrosion rate increased with increasing rotating speed due to the high mass transfer coefficient and formation of non-protective akaganeite β- FeO(OH) and goethite α- FeO(OH) corrosion scale at the electrode surface.The corrosion rate was lowest at 0 rpm.The corrosion rate decreased in both static and dynamic conditions with increasing immersion time. The decrease in corrosion rate is attributed to the deposition of corrosion products on the electrode surface. SEM results revealed that the rougher surface exhibited a great tendency toward pitting corrosion.
Resumo:
This article discusses two key issues in REDD+ design and implementation at the national level – carbon rights, and benefit sharing. Both carbon rights and benefit sharing can be understood as new legal concepts (although they build on existing law), and as legal concepts they offer a framework for addressing related areas of REDD+ policy. Many countries are currently considering how to manage carbon rights and benefit sharing issues, including Cambodia and Kenya. Both of these countries host existing forest carbon projects and are also in the process of designing national REDD+ programmes. This article uses a conceptual framework for carbon rights and benefit sharing derived from legal analysis to consider the cases of both Cambodia and Kenya, and also includes a general discussion of the challenges countries might encounter when considering how to manage carbon rights and benefit sharing in the context of REDD+ implementation.
Resumo:
The social economy as a regional development actor is gaining greater attention given its purported ability to address social and environmental problems. This growth in interest is occurring within a global environment that is calling for a more holistic understanding of development compared to traditionally economic-centric conceptions. While regional development policies and practices have long considered for-profit businesses as agents for regional growth, there is a relatively limited understanding of the role of the social economy as a development actor. The institutional environment is a large determinant of all kinds of entrepreneurial activity, and therefore understanding the relationships between the social economy and broader regional development processes is warranted. This paper moves beyond suggestions of an economic-centric focus of regional development by utilising institutional logics as a theoretical framework for understanding the role of social enterprise in regional development. A multiple case study of ten social enterprises in two regional locations in Australia suggests that social enterprise can represent competing logics to economic-centric institutional values and systems. The paper argues that dominant institutional logics can constrain or promote the inter-play between the social and the economic aspects of development, in the context of social enterprise.
Resumo:
Nanohybrids consisting of both carbon and pseudocapacitive metal oxides are promising as high-performance electrodes to meet the key energy and power requirements of supercapacitors. However, the development of high-performance nanohybrids with controllable size, density, composition and morphology remains a formidable challenge. Here, we present a simple and robust approach to integrating manganese oxide (MnOx) nanoparticles onto flexible graphite paper using an ultrathin carbon nanotube/reduced graphene oxide (CNT/RGO) supporting layer. Supercapacitor electrodes employing the MnOx/CNT/RGO nanohybrids without any conductive additives or binders yield a specific capacitance of 1070 F g−1 at 10 mV s−1, which is among the highest values reported for a range of hybrid structures and is close to the theoretical capacity of MnOx. Moreover, atmospheric-pressure plasmas are used to functionalize the CNT/RGO supporting layer to improve the adhesion of MnOx nanoparticles, which results in theimproved cycling stability of the nanohybrid electrodes. These results provide information for the utilization of nanohybrids and plasma-related effects to synergistically enhance the performance of supercapacitors and may create new opportunities in areas such as catalysts, photosynthesis and electrochemical sensors
Resumo:
Carbon nanotubes (CNTs) and graphene are two representative nanomaterials comprised of purely element carbon [1,2]. Graphene is the two-dimensional, hexagonal sp2-carbon ring networks with one atomic layer thickness, while CNTs can be envisaged as one or several graphene sheets concentrically rolled up into a one-dimensional cylindrical structure, so-called singlewalled (SW) or multi-walled (MW) CNTs, respectively. Figure 12.1 shows the schematic diagram of structures of graphene, SWCNT and MWCNT. Owing to their exceptional mechanical, electrical, optical and thermal properties, CNTs and graphene have been widely considered as a new type of materials with great potentials to revolutionalize many of the biological and medical fields [3–5].
Resumo:
Many protocols have been used for extraction of DNA from Thraustochytrids. These generally involve the use of CTAB, phenol/chloroform and ethanol. They also feature mechanical grinding, sonication, N2 freezing or bead beating. However, the resulting chemical and physical damage to extracted DNA reduces its quality. The methods are also unsuitable for large numbers of samples. Commercially-available DNA extraction kits give better quality and yields but are expensive. Therefore, an optimized DNA extraction protocol was developed which is suitable for Thraustochytrids to both minimise expensive and time-consuming steps prior to DNA extraction and also to improve the yield. The most effective method is a combination of single bead in TissueLyser (Qiagen) and Proteinase K. Results were conclusive: both the quality and the yield of extracted DNA were higher than with any other method giving an average yield of 8.5 µg/100 mg biomass.
Resumo:
Hybrid urchin-like nanostructures composed of a spherical onion-like carbon (OLC) core and MoS2 nanoleaves were synthesized by a simple solvothermal method followed by thermal annealing treatment. Compared to commercial MoS2 powder, MoS2/OLC nanocomposites exhibit enhanced electrochemical performance as anode materials of lithium-ion batteries (LIBs) with a specific capacity of 853 mA h g−1 at a current density of 50 mA g−1 after 60 cycles, and a moderate initial coulombic efficiency of 71.1%. Furthermore, a simple pre-lithiation method based on direct contact of lithium foil with MoS2/OLC nano-urchins was used to achieve a very high coulombic efficiency of 97.6% in the first discharge/charge cycle, which is at least 26% higher compared to that of pristine MoS2/OLC nano-urchins. This pre-lithiation method can be generalized to develop other carbon-metal sulfide nanohybrids for LIB anode materials. These results may open up a new avenue for the development of the next-generation high-performance LIBs.