1,185 research outputs found
Green chemistry and green engineering in China: drivers, policies and barriers to innovation
With the worldâs largest population and consistently rapid rates of economic growth, China faces a choice of whether it will move towards a more sustainable development trajectory. This paper identifies the different factors driving innovation in the fields of green chemistry and green engineering in China, which we find to be largely driven by energy efficiency policy, increasingly strict enforcement of pollution regulations, and national attention to cleaner production concepts, such as âcircular economy.â We also identify seven key barriers to the development and implementation of green chemistry and engineering in China. They are (1) competition between economic growth and environmental agendas, (2) regulatory and bureaucratic barriers, (3) availability of research funding, (4) technical barriers, (5)workforce training, (6) industrial engineering capacity, and (7) economic and financial barriers. Our analysis reveals that the most crucial barriers to green chemistry and engineering nnovations in China appear to be those that arise from competing priorities of economic growth and environmental protection as well as the technical challenges that arise from possessing a smaller base of experienced human capital. We find that there is a great deal of potential for both the development of the underlying science, as well as its implementation throughout the chemical enterprise, especially if investment occurs before problems of technological lock-in and sunk costs emerge
Book review: green consumption: the global rise of eco-chic edited by Bart Barendregt and Rivke Jaffe
Green lifestyles and ethical consumption have become increasingly popular strategies in moving towards environmentally-friendly societies and combating global poverty. This book aims to scrutinize the emergent phenomenon of âeco-chicâ: a combination of lifestyle politics, environmentalism, spirituality, beauty and health. Case studies cover Basque sheep cheese production and Ghanaian Afro-chic hairstyles to Asian tropical spa culture and Dutch fair-trade jewellery initiatives. For those interested in sustainable consumption, this book is an interesting look at the intersection of ethics, fashion, and power from a largely anthropological perspective, writes Kira Matus
Synchronization and multi-mode dynamics of mutually coupled semiconductor lasers
Dynamics of coupled semiconductor lasers is investigated by numerical simulations. A realistic laser simulation engine is used to study the synchronization and dynamical regime in two mutually coupled Fabry-Perot and/or DFB lasers. Both, single- and multi-mode operation regimes are studied with emphasis on the role of the multiple laser-cavity modes. Our findings indicate that the two laser synchronize within each laser-cavity mode, while the synchronization across different cavity modes is significantly weaker
The grapevine Pectin Methylesterases gene family and its involvement in Botrytis bunch rot control
Plant Pectin Methylesterases (PMEs) represent a group of tissue-specific and developmentally regulated proteins. The gene family is involved in the plant cell wall (CW) remodelling process, by the control of the degree of cell wall pectin methylesterification. Pectin methylesterification also influence the susceptibility to pathogens as Botrytis cinerea (Bc), a necrotrophic fungus responsible of the Botrytis bunch rot in grapevine. In Botrytis, PME as well as other CW degrading enzymes have been identified as virulence factors. To further characterize the PME gene family and its role in the Botrytis bunch rot, the latest genome assembly and annotation were revised and through sequence homology search, a total of 63 PME domain containing proteins were identified, 16 more than a previous identification in grapevine. The in-silico analyses of the family by means of the Vitis gene expression database VESPUCCI as well as Aggregated Gene Co-expression Network approach (AggGCNs) allowed us to identify and enrich gene co-expression modules and build gene co-expression networks. Interestingly, one of the co-expression modules showed a high modulation in presence of Botrytis cinerea infection and particular attention was paid to it. To investigate the contribution of the genes of that module, their expression level in different organs and developmental stages from two grapevine cultivars with divergent Bc susceptibility was investigated. Furthermore, berries were artificially infected with Bc at mature stage to evaluate PME gene expression level and their possible role in the grapevine bunch rot susceptibility. The results obtained contribute to characterize the grapevine PME gene family and the role of specific members in the grapevine-Bc interaction and to select PME genes candidate to the control of Botrytis bunch rot in grapevine
Razonamiento matemĂĄtico a travĂ©s del uso de tecnologĂas digitales: experiencias de aula en el contexto de un diplomado en la U.D.P
Recientemente se ha puesto de relieve en el currĂculum escolar chileno, la importancia de trabajar el razonamiento matemĂĄtico desde los primeros años escolares. La masificaciĂłn del uso de tecnologĂas digitales en la vida cotidiana y en el trabajo, se presenta como una gran oportunidad para implementar modelos de enseñanza que propongan el desarrollo de estas habilidades. En este trabajo, se reporta la experiencia de un grupo de profesores de una comuna de San JoaquĂn, en el contexto de un Diplomado en EducaciĂłn MatemĂĄtica y TecnologĂas Digitales organizado por el CDPD de la Universidad Diego Portales. En particular se describe, modelos de enseñanza y tipos de recursos digitales que fueron presentados en el programa y que favorecerĂan el desarrollo del razonamiento matemĂĄtico, segĂșn la literatura especializada. Como resultado, se muestra los tipos de recursos y modelos pedagĂłgicas especĂficos que fueron implementadas por este grupo de profesores con el objetivo de favorecer el razonamiento matemĂĄtico en sus estudiantes de enseñanza bĂĄsica
Charge-Stripe Order and Superconductivity in
A combined resistivity and hard x-ray diffraction study of superconductivity
and charge ordering in , as a function of Pt
substitution and externally applied hydrostatic pressure, is presented.
Experiments are focused on samples near the critical composition where competition and switching between charge order and
superconductivity is established. We show that charge order as a function of
pressure in is preempted - and hence
triggered - by a structural transition. Charge ordering appears uniaxially
along the short crystallographic (1,0,1) domain axis with a
modulation. Based on these results we
draw a charge-order phase diagram and discuss the relation between stripe
ordering and superconductivity.Comment: 8 pages, 4 figures: Accepted in Scientific Report
Quantum Lattice Fluctuations and Luminescence in C_60
We consider luminescence in photo-excited neutral C_60 using the
Su-Schrieffer-Heeger model applied to a single C_60 molecule. To calculate the
luminescence we use a collective coordinate method where our collective
coordinate resembles the displacement of the carbon atoms of the Hg(8) phonon
mode and extrapolates between the ground state "dimerisation" and the exciton
polaron. There is good agreement for the existing luminescence peak spacing and
fair agreement for the relative intensity. We predict the existence of further
peaks not yet resolved in experiment. PACS Numbers : 78.65.Hc, 74.70.Kn,
36.90+
The Solar Spectrum in the Atacama Desert
The Atacama Desert has been pointed out as one of the places on earth where the highest surface irradiance may occur. This area is characterized by its high altitude, prevalent cloudless conditions and relatively low columns of ozone and water vapor. Aimed at the characterization of the solar spectrum in the Atacama Desert, we carried out in February-March 2015 ground-based measurements of the spectral irradiance (from the ultraviolet to the near infrared) at seven locations that ranged from the city of Antofagasta (on the southern pacific coastline) to the Chajnantor Plateau (5,100 m altitude). Our spectral measurements allowed us to retrieve the total ozone column, the precipitable water, and the aerosol properties at each location. We found that changes in these parameters, as well as the shorter optical path length at high-altitude locations, lead to significant increases in the surface irradiance with the altitude. Our measurements show that, in the range 0?5100 m altitude, surface irradiance increases with the altitude by about 27% in the infrared range, 6% in the visible range, and 20% in the ultraviolet range. Spectral measurements carried out at the Iza?a Observatory (Tenerife, Spain), in Hannover (Germany) and in Santiago (Chile), were used for further comparisons
Global Health and Economic Impacts of Future Ozone Pollution
Abstract and PDF report are also available on the MIT Joint Program on the Science and Policy of Global Change website (http://globalchange.mit.edu/).We assess the human health and economic impacts of projected 2000-2050 changes in ozone pollution using the MIT Emissions Prediction and Policy Analysis-Health Effects (EPPA-HE) model, in combination with results from the GEOS-Chem global tropospheric chemistry model that simulated climate and chemistry effects of IPCC SRES emissions. We use EPPA to assess the human health damages (including acute mortality and morbidity outcomes) caused by ozone pollution and quantify their economic impacts in sixteen world regions. We compare the costs of ozone pollution under scenarios with 2000 and 2050 ozone precursor and greenhouse gas emissions (SRES A1B scenario). We estimate that health costs due to global ozone pollution above pre-industrial levels by 2050 will be ) and that acute mortalities will exceed 2 million. We find that previous methodologies underestimate costs of air pollution by more than a third because they do not take into account the long-term, compounding effects of health costs. The economic effects of emissions changes far exceed the influence of climate alone.United States Department of Energy, Office of
Science (BER) grants DE-FG02-94ER61937 and DE-FG02-93ER61677, the United States
Environmental Protection Agency grant EPA-XA-83344601-0, and the industrial and foundation
sponsors of the MIT Joint Program on the Science and Policy of Global Change
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