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1.
Nature ; 524(7565): 335-8, 2015 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-26289204

RESUMEN

Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = ±7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon).


Asunto(s)
Carbono/análisis , Materiales de Construcción/provisión & distribución , Combustibles Fósiles/estadística & datos numéricos , Dióxido de Carbono/análisis , Secuestro de Carbono , China , Cambio Climático , Carbón Mineral/estadística & datos numéricos , Árboles/metabolismo , Incertidumbre
5.
Environ Sci Pollut Res Int ; 29(3): 4232-4245, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34405327

RESUMEN

Logistics network is one of the most important parts of supply chains with significant share in achieving sustainability across them. In this paper, we investigate a new multi-objective mixed integer linear programming model for the design of multimodal logistics network. A bi-objective mathematical model is introduced and two conflicting objectives including the minimization of total cost and the total environmental impact are taken into account. Effective environmental life cycle assessment-based method is incorporated in the model to estimate the relevant environmental impacts. Due to budget constraints, financing decisions for facility construction are considered in the proposed model. To cope with the model objective functions, the augmented ε-constraint method is applied. Computational analysis is also provided by using a cement multimodal rail-road logistics network case study to present the significance of the proposed model. Results show that utilizing the proposed multi-period optimization model influences the location of multimodal terminals and their construction time. Also, the results show that the use of the proposed model enhances the efficiency of terminals. On the other hand, computational results indicate that preferences of decision-makers and the importance of environmental objective have significant impacts on the topology of transportation network.


Asunto(s)
Materiales de Construcción/provisión & distribución , Modelos Teóricos , Transportes , Ambiente , Programación Lineal
7.
Disaster Med Public Health Prep ; 11(3): 285-289, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27976602

RESUMEN

OBJECTIVES: Typhoon Haiyan hit the Philippines in November 2013 and left a trail of destruction. As part of its emergency response, Médecins Sans Frontières distributed materials for reconstructing houses and boats as standardized kits to be shared between households. Community engagement was sought and communities were empowered in deciding how to make the distributions. We aimed to answer, Was this effective and what lessons were learned? METHODS: A cross-sectional survey using a semi-structured questionnaire was conducted in May 2014 and included all community leaders and 269 households in 22 barangays (community administrative areas). RESULTS: All houses were affected by the typhoon, of which 182 (68%) were totally damaged. All households reported having received and used the housing material. However, in 238 (88%) house repair was incomplete because the materials provided were insufficient or inappropriate for the required repairs. CONCLUSION: This experience of emergency mass distribution of reconstruction or repair materials of houses and boats led by the local community was encouraging. The use of "standardized kits" resulted in equity issues, because households were subjected to variable degrees of damage. A possible way out is to follow up the emergency distribution with a needs assessment and a tailored distribution. (Disaster Med Public Health Preparedness. 2017;11:285-289).


Asunto(s)
Industria de la Construcción/métodos , Tormentas Ciclónicas , Medicina de Desastres/métodos , Medicina de Desastres/tendencias , Centros Comunitarios de Salud/tendencias , Materiales de Construcción/provisión & distribución , Estudios Transversales , Humanos , Evaluación de Necesidades/tendencias , Filipinas , Encuestas y Cuestionarios , Recursos Humanos
8.
ScientificWorldJournal ; 3: 308-18, 2003 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-12806096

RESUMEN

The world production of cement has greatly increased in the past 10 years. This trend is the most significant factor affecting technological development and the updating of manufacturing facilities in the cement industry. Existing technology for the production of cement clinker is ecologically damaging; it consumes much energy and natural resources and also emits pollutants. A new approach to the production of blended or high-volume mineral additive (HVMA) cement helps to improve its ecological compatibility. HVMA cement technology is based on the intergrinding of portland cement clinker, gypsum, mineral additives, and a special complex admixture. This new method increases the compressive strength of ordinary cement, improves durability of the cement-based materials, and--at the same time--uses inexpensive natural mineral additives or industrial by-products. This improvement leads to a reduction of energy consumption per unit of the cement produced. Higher strength, better durability, reduction of pollution at the clinker production stage, and decrease of landfill area occupied by industrial by-products, all provide ecological advantages for HVMA cement.


Asunto(s)
Materiales de Construcción/provisión & distribución , Materiales de Construcción/normas , Ecología/normas , Industrias/tendencias , Industrias/instrumentación
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