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Flexible butyl interconnection segments are synthetically incorporated into an electronically conductive poly(pyrene methacrylate) homopolymer and its copolymer. The insertion of butyl segment makes the pyrene polymer more flexible, and can better accommodate deformation. This new class of flexible and conductive polymers can be used as a polymer binder and adhesive to facilitate the electrochemical performance of a silicon/graphene composite anode material for lithium ion battery application. They act like a “spring” to maintain the electrode mechanical and electrical integrity. High mass loading and high areal capacity, which are critical design requirements of high energy batteries, have been achieved in the electrodes composed of the novel binders and silicon/graphene composite material. A remarkable area capacity of over 5 mAh/cm2 and volumetric capacity of over 1700 Ah/L have been reached at a high current rate of 333 mA/g.

In China, the power sector is currently the largest carbon emitter and the transportation sector is the fastest-growing carbon emitter. This paper proposes a model of solar-powered charging stations for electric vehicles to mitigate problems encountered in China’s renewable energy utilization processes and to cope with the increasing power demand by electric vehicles for the near future. This study applies the proposed model to Shenzhen City to verify its technical and economic feasibility. Modeling results showed that the total net present value of a photovoltaic power charging station that meets the daily electricity demand of 4500 kWh is $3,579,236 and that the cost of energy of the combined energy system is $0.098/kWh. In addition, the photovoltaic powered electric vehicle model has pollutant reduction potentials of 99.8%, 99.7% and 100% for carbon dioxide, sulfur dioxide, and nitrogen oxides, respectively, compared with a traditional gasoline-fueled car. Sensitivity analysis results indicated that interest rate has a relatively strong influence on COE (Cost of Energy). An increase in the interest rate from 0% to 6% increases COE from $0.027/kWh to $0.097/kWh. This analysis also suggests that carbon pricing promotes renewable energy only when the price of carbon is above $20/t.

This paper analyses the impact of postponing global mitigation action on abatement costs and energy systems changes in China and India. It compares energy-system changes and mitigation costs from a global and two national energy-system models under two global emission pathways with medium likelihood of meeting the 2 °C target: a least-cost pathway and a pathway that postpones ambitious mitigation action, starting from the Copenhagen Accord pledges. Both pathways have similar 2010–2050 cumulative greenhouse gas emissions. The analysis shows that postponing mitigation action increases the lock-in in less energy efficient technologies and results in much higher cumulative mitigation costs. The models agree that carbon capture and storage (CCS) and nuclear energy are important mitigation technologies, while the shares of biofuels and other renewables vary largely over the models. Differences between India and China with respect to the timing of emission reductions and the choice of mitigation measures relate to differences in projections of rapid economic change, capital stock turnover and technological development. Furthermore, depending on the way it is implemented, climate policy could increase indoor air pollution, but it is likely to provide synergies for energy security. These relations should be taken into account when designing national climate policies.

Owing to the current serious environmental and climate problems, the energy industry must focus on the problem of energy utilization rates. High-temperature gas-cooled reactors (HTGRs) are fourth-generation reactors, characterized by high outlet temperatures. The combined cycle is composed of the gas turbine and steam turbine cycles, and it can realize the cascade utilization of high-quality energy. It is a highly competitive power conversion scheme for HTGRs. In this study, the matching characteristics of the combined cycle coupled with HTGRs are revealed through the progressive optimization method. In the combined cycle coupled with HTGRs, the topping and bottoming cycle are both closed cycles, therefore, the optimization for cycle efficiency is to match the topping and bottoming cycles. For a combined cycle with subcritical steam parameters, there are two extreme values of the combined cycle efficiency that have different power ratios. The characteristics revealed in this study are unique to closed combined cycle coupled with HTGRs.

Study Region Mekong River Basin and surrounding areas. Study Focus: This study investigated the impacts of climate change on future meteorological and hydrological droughts in the Mekong River Basin and its surrounding areas. Our work is based on the output of five global climate models (GCMs) and simulations using the geomorphology-based hydrological model (GBHM) for the historical (1975–2004), near future (2010–2039), middle future (2040–2069), and far future (2070–2099) periods. The meteorological droughts in the study area were measured using SPI and SPEI, while the hydrological droughts were measured using SSI. New Hydrological Insights for the Region: The results suggest that droughts will generally reduce in the future over most of the study area, but will be more unevenly distributed with an eastward migration as compared to the historical period. Both meteorological and hydrological droughts will intensify in the near future, but will then reduce in intensity. Meteorological droughts will increase in the northeastern areas in the near future, followed by migration towards the south. Hydrological droughts showed similar aggravation followed by reduction, with upstream areas showing greater variability. In the general context of drought alleviation, southwestern China and the Mekong River estuary may suffer from a continuously increasing drought intensity in the future. This finding is based on 100-year extreme drought events.

When extreme weather events occur, people often turn to social media platforms to share information, opinions and experiences. One of the topics commonly discussed is the role climate change may or may not have played in influencing an event. Here, we examine Twitter posts that mentioned climate change in the context of three high-magnitude extreme weather events – Hurricane Irene, Hurricane Sandy and Snowstorm Jonas – in order to assess how the framing of the topic and the attention paid to it can vary between events. We also examine the role that contextual factors can play in shaping climate change coverage on the platform. We find that criticism of climate change denial dominated during Irene, while political and ideological struggle frames dominated during Sandy. Discourse during Jonas was, in contrast, more divided between posts about the scientific links between climate change and the events, and posts contesting climate science in general. The focus on political and ideological struggle frames during Sandy reflects the event's occurrence at a time when the Occupy movement was active and the 2012 US Presidential Election was nearing. These factors, we suggest, could also contribute to climate change being a more prominent discussion point during Sandy than during Irene or Jonas. The Jonas frames, meanwhile, hint at lesser public understanding of how climate change may influence cold weather events when compared with tropical storms. Overall, our findings demonstrate how event characteristics and short-term socio-political context can play a critical role in determining the lenses through which climate change is viewed.

Global warming due to anthropogenic activities has alarming effects on biodiversity. It could negatively impact the interactions between predators and their prey by shifting or eliminating their suitable habitats. The predator common leopard (Panthera pardus) and two prey species, Himalayan grey goral (Naemorhedus goral) and Himalayan grey langur (Semnopithecus ajax) play important roles in balancing the forest ecosystem in northern Pakistan. The common leopard is listed as a Vulnerable species on the IUCN Red List, while grey goral and grey langur are listed as Near Threatened and Endangered respectively. For this study, we used Maximum Entropy Model (MaxEnt) to model the current (average for 1950–2000) and future (in 2070) suitable habitat for each of these species using three General Circulation Models [GCMs; i.e. Beijing Climate Center Climate System Model (BCC-CSM1–1), Community Climate System Model (CCSM4), and Hadley Global Environment Model 2 (HadGEM2-AO)]. We used two climate change emission scenarios, i.e., a moderate carbon emission scenario (RCP4.5) and an extreme carbon emission scenario (RCP8.5). Our results indicated that an area of 18,360 km2, 34,142 km2 and 10,636 km2 are currently suitable for the common leopard, grey goral, and grey langur, respectively. In the future, common leopard, grey goral and grey langur were predicted to lose over 11%, 43%, and 44% of currently inhabited areas under the most severe climate scenario (RCP8.5), respectively. Overall, 56–89% of the current suitable habitat area was predicted as stable suitable habitat for all the species. The study projected that currently, 14,321 km2 is suitable for both common leopard and grey goral. Whereas, 7096 km2 of current habitat is suitable for both common leopard and grey langur. Overlapping areas were predicted to be reduced in the future (due to fluctuations in temperature and precipitation), ranging from 2% (under RCP8.5) to 8% (under RCP45) for areas suitable for common leopard and grey goral, and from 30% (under RCP4.5) to 47% (under RCP8.5) for areas suitable for common leopard and grey langur, respectively. Most of the overlapping areas that remained suitable were projected between the altitudinal range of 1000 m – 3000 m for common leopard and grey goral, and from 2000 m to 4000 m for common leopard and grey langur. Our results inform management plans and conservation strategies (e.g., establishment of new or improving the status of existing protected areas) for mitigating the impacts of climate change on endangered predator and prey species in the northern Pakistan.