How do carbon trading price and carbon tax rate affect power project portfolio investment and carbon emission: An analysis based on uncertainty theory.

Responding to the social, economic, and environmental call to resolve current sustainability challenges, the concern about carbon dioxide emission reduction should be incorporated into the power investment decision process. Reflecting the low carbon emission requirement, this paper proposes a new optimization model for power project portfolio selection that simultaneously considers both of carbon emission trading scheme and carbon tax imposition. In this model, the initial investment outlay, the power sale price, the carbon trading price, and carbon tax rate are treated as uncertain variables considering the fast-changing environment and complex market situation. Incorporating the constraint on whether the carbon quota is exceeded into the model, two investment strategies are proposed for investors. Using the proposed model, the impact of the rises in carbon trading price and carbon tax rate on the investor's investment strategy selection and the carbon emission is simulated and analyzed through a case study. When the expected carbon price is 203.50 RMB/tCO2-eq or less, a company should invest based on the strategy that annual emissions exceed the quota to obtain a maximum expected NPV which is larger than 408588 million RMB. When future carbon prices are 352.00, 500.50 and 649.00 RMB/tCO2-eq, the government should impose carbon tax rates of 30, 30, and 40 RMB/tCO2 on a power company, respectively, to obtain carbon emission reduction effect. At last, to see the contrast effect of the results from simultaneous implementation of both carbon trading and carbon tax, the results considering the carbon trading alone or carbon tax alone are discussed, respectively.

An electric double layer of colloidal particles in salt-free concentrated suspensions including non-uniform size effects and orientational ordering of water dipoles.

The response of a suspension under a variety of static or alternating external fields strongly depends on the equilibrium electric double layer that surrounds the colloidal particles in the suspension. The theoretical models for salt-free suspensions can be improved by incorporating non-uniform size effects and orientational ordering of water dipoles neglected in previous mean-field approaches, which are based on the Poisson-Boltzmann approach. Our model including non-uniform size effects and orientational ordering of water dipoles seems to have quite a promising effect because the model can predict the phenomena like a heavy decrease in relative permittivity of the suspension and counterion stratification near highly charged colloidal particles. In this work we numerically obtain the electric potential, the counterion concentration and the relative permittivity around a charged particle in a concentrated salt-free suspension corrected by non-uniform size effects and orientational ordering of water dipoles. The results show the worth of such corrections for medium to high particle charges at every particle volume fraction. We conclude that non-uniform size effects and orientational ordering of water dipoles are necessary for the development of new theoretical models to study non-equilibrium properties in concentrated colloidal suspensions.

Ab initio study of superoxide dismutase (SOD) and catalase activity of EUK-134.

Dismutation reaction of superoxide radical catalyzed by EUK-134 has lower activation energy than non-catalytic reaction, and therefore, EUK-134 catalyzes dismutation reaction of superoxide radical. For non-catalytic dismutation reaction of hydrogen peroxide, there are three possible reaction paths, among which MEP3 has the lowest activation energy, and therefore, is thought to be the most probable reaction path. Dismutation reaction of hydrogen peroxide catalyzed by EUK-134 occurs in two successive steps and has lower energy barrier than non-catalytic dismutation reaction, and therefore, EUK-134 is thought to catalyze the dismutation reaction of hydrogen peroxide. HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) and ESP-fitted charge analysis of EUK-134 indicate that Mn atom plays an electron acceptor and donor for dismutation reactions of superoxide radical and hydrogen peroxide catalyzed by EUK-134, respectively.

Ab initio study of photocatalytic characteristics of graphitic carbon nitride assisted by oxalic acid.

Using density functional theory, structural, electronic, and optical properties of GCN (graphitic carbon nitride) and OAGCN (graphitic carbon nitride combined with oxalic acid) were studied. By comparing HOMOs and LUMOs and excitonic binding energies, OAGCN has lower photoinduced electron-hole recombination rate than GCN. VBM and CBM levels of GCN and OAGCN were calculated, which shows that for GCN, only the electron at CBM contributes to produce radicals for removing pollutants, and for OAGCN, both the electron at CBM and the hole at VBM contribute to produce radicals for removing pollutants. In total, it can be said that OAGCN has higher photocatalytic activity than GCN.