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The effect of a LiF interlayer on the photovoltaic characteristics of the ITO/PEDOT:PSS/MEH-PPV:C (0wt%, 10wt% and 20wt%)/Al composite device has been investigated. For undoped MEH-PPV devices (0wt%), the modified devices show an increase in both the V and I. However, for composite devices (10wt% and 20wt%), the modified devices show an increase in the V, but a decline in the I. These changes of photovoltaic properties are attributed to the dipole layer between composite film and Al cathode due to the introduction of LiF layer. This dipole layer equivalently lowers the work function of cathode, which enhances the build-in potential and thus V. The different effects of LiF on the undoped and composite devices are caused by the different LUMO of C and MEH-PPV.

The emergence and development of the power-to-gas (P2G) technique have made the bidirectional energy flow between power and natural gas systems possible. P2G represents a key technique in the emerging energy internet, and promotes the integration of multi-energy systems. By transforming electricity to gas, existing gas storage facilities can be used to mitigate the volatility of renewable energy generation. The modeling of future complex multi-energy systems with P2G functions is presented based on the "energy hub" framework, and a coordinated optimization model presented. A game-theory-based method is next proposed to attain market equilibrium in a multi-energy system. A 4-bus sample multi-energy system and a simplified Victoria gas-electricity combined network system in Australia are adopted for demonstrating the effectiveness of the presented optimization model and solving algorithm.

Co-integration analysis and Granger causality test were applied in this paper,using the panel statistical data of annual macro-economy in year 1978～2006,the dependent relation between the amount of China energy consumption and gross domestic product was checked.In the further step,an analysis was made to prove the correlation between different industry economic growth and energy consumption in China.An evidence-based study showed that co-integration relation exists between the gross of China energy consumption and the GDP,and the two variables possess bi-directional causality.The energy consumption for the secondary industry has a markedly stimulative effect.This paper also explained the short-term behavior of energy demands by error correcting model.

Water use efficiency (WUE) of an ecosystem is an important index to measure the degree of coupling of the carbon and water cycles. The WUE of a cropland ecosystem in Anhui Province was estimated and the spatio-temporal distribution of cropland WUE was analyzed to explore its influencing factors, which will be of great significance for scientific allocation and rational utilization of water resources in the cropland region. This study focused on the application of data from moderate-resolution imaging spectroradiometer (MODIS) and meteorological data, estimated the cropland WUE, analyzed the spatio-temporal characteristics of cropland WUE in Anhui Province over the last 15 years, and evaluated the relationship of WUE with climatic factors. The results showed that 1) Between 2000 and 2014, the average annual cropland WUE for Anhui Province was 1.54 gC mm 1 m, ranging from 1.38 to 1.66 gC mm 1 m. As a whole, the annual growth trend of cropland WUE was 0.011 gC mm 1 m, and cropland WUE had a strong spatial variability in Anhui Province, where it was higher in the north and lower in the southern part of the province. The cropland WUE north of the Huaihe River was higher than that of the province as a whole, while that of the Huaihe River was lower than the province average. 2) The variation of cropland WUE in Anhui Province showed a bimodal change pattern with obvious seasonal variation, in the order of spring > autumn > summer > winter. Taking Huaihe as the boundary, the changing trends of the cities in the north and the south were slightly different. The maximum value south of Huaihe was in A p r i l, while that north of Huaihe was the highest in March. 3) The dynamic change of cropland WUE in Anhui Province was closely related to temperature and rainfall. The regions with cropland WUE changes resulting from non-climate factors made up 81.42% of the total area of cropland in the province, followed by that mainly affected by precipitation (17.14%) and temperature (0 . 7 3 %), while the combination of ...

A high pressure supercritical CO geochemical reactor was used to simulate the CO sequestration process into deep coal seam under around 40°C and 9.8 MPa for 72 hours. The changes of pore structure of different rank coal samples with and without the supercritical CO treatment were investigated by helium pycnometer and mercury porosimetry. The results show that the true density of anthracite increase from 1.51 g/cm to 1.59 g/cm while that of other rank samples have no significant changes after being treated by the HP-ScCO-HO system. All the bulk densities decrease, of which lignite and low volatile bituminous decreased by 0.1 g/cm. The growth rate of total pore volume and porosity of lignite are 85% and 118% respectively, which are mainly attributed to the increase in macropores. Pore structures of coal during CO sequestration are mainly influenced by macropores and mesopores in low rank coals, while in high rank coals mainly by micropores, which increase the surface area of coal. As shown in anthracite, the surface area increase from 24.3 m/g to 27.6 m/g, which accordingly enhance the gas adsorption. The "ink-bottle" pores are influenced during CO sequestration process from analysis on hysteresis of the extrusion curves.

The transport mechanism of photogenerated carriers in the composite films based on poly[2-methoxy, 5-(2'-ethyl-hexyloxy)-1,4,-phenylene-vinylene] (MEH-PPV) doped with CuS nanoparticles is investigated by the steady-state photo-current spectra and dynamic double-pulse photocurrent response. An obvious charging effect is found at lower concentration of CuS nanoparticles, while at high concentration, the same feature is absent. The charging effect is attributed to charge accumulation at the interface between MEH-PPV and CuS nanoparticles, which directly destroys the photocurrent responses of composite devices. It is concluded that doping CuS into MEH-PPV at low concentration causes trap states, and filling and emptying traps leads to charging and discharging effect respectively. At high concentration of CuS nanoparticles, the aggregation scale becomes larger and the double polar transport of charge carriers is improved, which inhibits the charge accumulation at the interface of MEH-PPV/CuS.