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Atmospheric concentrations of the greenhouse gas nitrous oxide (N(2)O) have increased significantly since pre-industrial times owing to anthropogenic perturbation of the global nitrogen cycle, with animal production being one of the main contributors. Grasslands cover about 20 per cent of the temperate land surface of the Earth and are widely used as pasture. It has been suggested that high animal stocking rates and the resulting elevated nitrogen input increase N(2)O emissions. Internationally agreed methods to upscale the effect of increased livestock numbers on N(2)O emissions are based directly on per capita nitrogen inputs. However, measurements of grassland N(2)O fluxes are often performed over short time periods, with low time resolution and mostly during the growing season. In consequence, our understanding of the daily and seasonal dynamics of grassland N(2)O fluxes remains limited. Here we report year-round N(2)O flux measurements with high and low temporal resolution at ten steppe grassland sites in Inner Mongolia, China. We show that short-lived pulses of N(2)O emission during spring thaw dominate the annual N(2)O budget at our study sites. The N(2)O emission pulses are highest in ungrazed steppe and decrease with increasing stocking rate, suggesting that grazing decreases rather than increases N(2)O emissions. Our results show that the stimulatory effect of higher stocking rates on nitrogen cycling and, hence, on N(2)O emission is more than offset by the effects of a parallel reduction in microbial biomass, inorganic nitrogen production and wintertime water retention. By neglecting these freeze-thaw interactions, existing approaches may have systematically overestimated N(2)O emissions over the last century for semi-arid, cool temperate grasslands by up to 72 per cent.

Abstract Stable aqueous TiO2 nanofluids with different particle (agglomerate) sizes and concentrations are formulated and measured for their static thermal conductivity and rheological behaviour. The nanofluids are then measured for their heat transfer and flow behaviour upon flowing upward through a vertical pipe in both the laminar and turbulent flow regimes. Addition of nanoparticles into the base liquid enhances the thermal conduction and the enhancement increases with increasing particle concentration and decreasing particle (agglomerate) size. Rheological measurements show that the shear viscosity of nanofluids decreases first with increasing shear rate (the shear thinning behaviour), and then approaches a constant at a shear rate greater than ∼100 s−1. The constant viscosity increases with increasing particle (agglomerate) size and particle concentration. Given the flow Reynolds number and particle size, the convective heat transfer coefficient increases with nanoparticle concentration in both the laminar and turbulent flow regimes and the effect of particle concentration seems to be more considerable in the turbulent flow regime. Given the particle concentration and flow Reynolds number, the convective heat transfer coefficient does not seem to be sensitive to the average particle size under the conditions of this work. The results also show that the pressure drop of the nanofluid flows is very close to that of the base liquid flows for a given Reynolds number.

Abstract Although the “resource curse” hypothesis has been supported by many empirical studies focusing on the transnational and regional levels, there has always been a point of contention about the proper method of estimating and selecting natural resource indicators in literature. This paper proposes a mixed estimation method for panel data of 10 typical oil and gas resource-based cities in China from 1998 to 2015. The results show that resource industry agglomeration can mirror the distribution and dependence on the resource industry by location rather than by merely measuring the influence of the relative scale of resource extraction on economic growth. Using resource industry agglomeration as the main explanatory variable for regional economic growth verifies the resource curse hypothesis and shows the nonlinear characteristics of the negative correlation between resources and economic growth. Despite mostly similar indicator parameter estimates, marked differences exist in measured effects for material capital investments and technological innovation investments. The result of using resource industry agglomeration as the main explanatory variable is basically consistent with the economic theory and is more in line with observed reality than the alternative indicator. The research conclusions can provide evidence and data for index selection in the studies on the mediating effect of resource curse transmission and international comparison.

In alkaline electrolyte, Ca2+ doped cobalt based coordination polymers transformed into Ca2+ doped ultrathin CoOOH nanosheets show enhanced OER activity.

Abstract This paper explores the relationships between travelers’ intentions to use low carbon travel modes, a set of socio-psychological variables, and the influence of government supported low carbon travel policies. Specifically, a Comprehensive Intention Determination Model (CIDM) is used to study residents’ low-carbon travel intentions, based on the theory of planned behavior (TPB) and value-belief-norm theory (VBN), and using structural equations modeling (SEM) applied to survey responses by 811 residents of the city of Tianjin, China. Low-carbon transport policies are shown to influence traveler intentions primarily through attitude, subjective and personal norms, awareness of consequence, and ascription of responsibility; and that combining positive social-psychological factors towards low-carbon awareness with effective low carbon transport policies can influence the residents’ willingness to choose low-carbon travel modes to a moderate degree.

3-(Hydroxy(phenyl)phosphoryl)propanoic acid (HPA) has a strong coordination ability for Zn2+/metal anodes which not only form sphere micelles that promote the uniform transmission of Zn2+ but also enhance the preferential adsorption on anodes.

AbstractA series of block copolymers with fixed length of the semiconductor‐block poly(3‐butylthiophene) (P3BT) and varying length of the insulator‐block polystyrene (PS) are synthesized. These copolymers are blended with phenyl‐C61‐butyric acid methyl ester (PCBM) for the bulk heterojunction photoactive layers. With appropriate insulator‐block length and donor–acceptor ratio, the power conversion efficiency increases by one order of magnitude compared with reference devices with pure P3BT/PCBM. PS blocks improve the miscibility of the active layer blends remarkably. The P3BT‐b‐PS crystallizes as nanorods with the P3BT core covered with the PS‐block, which creates a nanoscale tunneling barrier between donor and acceptor leading to more efficient transportation of charge carriers in the semiconductors.

Abstract Millions of tonnes (teragrams) of plastic waste are traded around the world every year, which plays an important role in partially substituting virgin plastics as a source of raw materials in plastic product manufacturing. In this paper, global plastic waste trade networks (GPWTNs) from 1988 to 2017 are established using the UN-Comtrade database. The spatiotemporal evolution of the GPWTNs is analyzed. Attention is given to the country ranks, inter- and intra-continental trade flows, and geo-visual communities in the GPWTNs. We also evaluate the direct and indirect impacts of China’s plastic waste import ban on the GPWTNs. The results show that the GPWTNs have small-world and scale-free properties and a core-periphery structure. The geography of the plastic waste trade is structured by Asia as the dominant importer and North America and Europe as the largest sources of plastic waste. China is the unrivaled colossus in the global plastic waste trade. After China’s import ban, the plastic waste trade flows have been largely redirected to Southeast Asian countries. Compared with import countries, export countries are more important for the robustness of GPWTNs. Clearly, developed countries will not announce bans on plastic waste exports; these countries have strong motivation to continue to shift plastic waste to poorer countries. However, the import bans from developing countries will compel developed countries to build new disposal facilities and deal with their plastic waste domestically.