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[en] Highlights: • Downscaling algorithms are revised and applied to obtain nation-level data. • Downscaled results of representative parties on economy and emission are analyzed. • Cancún pledges may lower the temperature increase to a great extent. • Cancún pledges may increase the unfairness among countries. • Downscaled nation-level data can be used for further study as basic dataset. - Abstract: Many countries pledged to reduce their greenhouse gas emissions by 2020 during the 2009 Copenhagen Accord and the 2010 Cancún Agreement. This paper evaluates the Cancún pledges from two aspects, namely, temperature increase and carbon Gini coefficient. The Model for the Assessment of Greenhouse-gas Induced Climate Change is used to calculate the temperature increase, and the carbon Gini coefficient is used to measure the equivalence of emission–reduction allocations. We first downscale regional business as usual (BAU) scenarios from integrated assessment models to the national level. Then, we combine the downscaled BAU with Cancún pledges to generate the emission trajectory of the pledges. We use emissions with and without pledges as input to assess the adequacy and fairness of the pledges by using temperature increase and carbon Gini coefficient, respectively. Based on the results, we show that the Cancún pledges would reduce the temperature increase to a great extent, but not enough to meet the 2 degree target. Due to the insufficient contribution from developed countries, the Cancún pledges will sacrifice equity among countries, especially between developed and developing countries. The common understanding of equity will be essential to bridge the mitigation gap toward meeting the 2 degree target
[en] Highlights: • First study on the co-benefits of mitigation measures in the cement sector in China. • We evaluate the economic value of damage of various pollutants at local level. • We evaluate 18 energy-saving technologies for 31 provinces in cement sector. • The value for the co-benefits ranged from 3 $/t CO2 to 39 $/t CO2. • The large spatial variations may justify stringent targets for richer provinces. - Abstract: We analyzed the impacts of incorporating local air quality improvement and environmental co-benefits into the climate policy and mitigation technology assessment of the cement sector in China. Local air quality can benefit from reducing greenhouse gas emissions, which consequently lowers abatement costs and strengthens the cost-effectiveness of mitigation technologies. We used a simplified approach to estimate environmental damage factors due to air pollution at the sub-national level in China. The calculated economic costs of environmental damage due to PM10, NOx, and SO2 were 7,714 $/t, 1,006 $/t, and 902 $/t, respectively. These values vary among the provinces. We found that most energy-saving technologies in the cement industry will create significant co-benefits, ranging from 3 $/t CO2 to 39 $/t CO2 at the national level; however, a tradeoff for carbon capture and storage (CCS) and energy-saving technologies also resulted with increased electricity consumption. Large spatial variations of co-benefits can be gained at the sub-national level and justify the enactment of more stringent climate policies in the wealthier regions in China
[en] Highlights: • Energy and water limit China’s sustainable development. • Current energy policies fail to address water saving issues. • The energy-water coefficient is estimated for both direct use and indirect use. • Water saving effects associated with energy-saving policies is calculated. • Water-energy nexus should be enhanced in key industrial sectors. - Abstract: Energy and water have become major factors limiting sustainable development in China. Energy efficiency and optimization of water management are critical for the healthy growth of the Chinese economy. Current national energy policies fail to adequately address water use issues. Similarly, current water policies do not consider the impact of energy consumption and greenhouse gas emissions. Consequently, few studies have investigated the relationship between energy consumption and water use. The present study analyzes the energy-water nexus in Chinese industries using input–output tables. Coefficients that characterize the relationship between energy consumption and water are used to describe the supply-consumption relationship between the water supply and primary energy sectors. Next, we calculate the water-saving effects associated with the enforcement of energy-saving policies in selected industrial sectors during the eleventh Five-year Plan, from 2005 to 2010. These calculations address the ferrous metals, non-ferrous metals, petrochemical engineering, building materials, and electricity industries as well as key light industries. Our findings indicate that energy-saving efforts in these industries will result in savings in water consumption. This study suggests that a cooperative relationship between water and energy conservation efforts should be an important factor in creating policies that encourage simultaneous savings of both resources. Additionally, the study indicates that government should promote water- and energy-saving techniques in key industrial sectors to encourage cooperative water and energy conservation
[en] Highlights: • The economic and environmental benefits of smart EVs/HPs are quantified. • This paper implements an advanced stochastic analytical framework. • Operating patterns and potential flexibility of EVs/HPs are sourced from UK trials. • A comprehensive set of case studies across UK future scenarios are carried out. - Abstract: This paper presents an advanced stochastic analytical framework to quantify the benefits of smart electric vehicles (EVs) and heat pumps (HPs) on the carbon emission and the integration cost of renewable energy sources (RES) in the future UK electricity system. The typical operating patterns of EVs/HPs as well as the potential flexibility to perform demand shifting and frequency response are sourced from recent UK trials. A comprehensive range of case studies across several future UK scenarios suggest that smart EVs/HPs could deliver measurable carbon reductions by enabling a more efficient operation of the electricity system, while at the same time making the integration of electrified transport and heating demand significantly less carbon intensive. The second set of case studies establish that smart EVs/HPs have significant potential to support cost-efficient RES integration by reducing: (a) RES balancing cost, (b) cost of required back-up generation capacity, and (c) cost of additional low-carbon capacity required to offset lower fuel efficiency and curtailed RES output while achieving the same emission target. Frequency response provision from EVs/HPs could significantly enhance both the carbon benefit and the RES integration benefit of smart EVs/HPs.
[en] PCCS in AP1000 includes two parts, namely a reinforced concrete containment, which is modeled as structural dynamic, and a gravity drain water tank, which is modeled as lumped masses known as sloshing mass, impulsive mass and rigid mass. Based on the seismic response characteristics of the water storage tank and the reinforced concrete containment, the conventional model and isolated model are built respectively. The optimal analysis of isolated layer parameters, namely the natural period and damping, are provided. Using the nuclear power plant dynamic characteristics and structural design codes, three models, namely conventional structure, isolated model on design code, and isolated model on the optimal parameter, are studied in MATLAB software. The seismic responses of all models are compared under the real earthquake ground motions. Results show that the isolated model with the optimal parameter provided by this paper has the best seismic function in all models. (authors)
[en] We consider direct detection prospects for a class of simplified models of fermionic dark matter (DM) coupled to left and right-handed Standard Model fermions via two charged scalar mediators with arbitrary mixing angle α. DM interactions with the nucleus are mediated by higher electromagnetic moments, which, for Majorana DM, is the anapole moment. After giving a full analytic calculation of the anapole moment, including its α dependence, and matching with limits in the literature, we compute the DM-nucleon scattering cross-section and show the LUX and future LZ constraints on the parameter space of these models. We then compare these results with constraints coming from Fermi-LAT continuum and line searches. Results in the supersymmetric limit of these simplified models are provided in all cases. We find that future direct detection experiments will be able to probe most of the parameter space of these models for O(100−200) GeV DM and lightest mediator mass ≲O(5%) larger than the DM mass. The direct detection prospects dwindle for larger DM mass and larger mass gap between the DM and the lightest mediator mass, although appreciable regions are still probed for O(200) GeV DM and lightest mediator mass ≲O(20%) larger than the DM mass. The direct detection bounds are also attenuated near certain “blind spots' in the parameter space, where the anapole moment is severely suppressed due to cancellation of different terms. We carefully study these blind spots and the associated Fermi-LAT signals in these regions.
[en] Graphical abstract: Fitting values of γ(Pre) predicted by the molar surface Gibbs energy model versus corresponding experimental one, γ(Exp), a good straight line was obtained and it can be seen that predicted surface tension and the corresponding experimental values are highly correlated (correlation coefficient squared, r"2 = 0.999, standard deviation, s = 0.112) and extremely similar (gradient = 0.999; intercept = 0.00592). - Highlights: • A semi-empirical model molar surface Gibbs energy model was put forward. • The predicted γ by the model and matching experimental ones are highly correlated. • By the concept of the molar Gibbs energy, a new Eötvös equation is obtained. - Abstract: The density and surface tension for the aqueous solution of the ionic liquid (IL) 1-hexyl-3-methylimidazolium acetate [C_6mim][OAc] with various molalities were measured at T = (288.15 to 318.15) K with an interval of T = 5 K. On the basis of Li’s model, as a new concept, the molar surface Gibbs energy of the ionic liquid solution was put forward and it was used to predict surface tension of aqueous [C_6mim][OAc]. The predicted values of the surface tension are highly correlated and extremely similar to the corresponding experimental values. It is worth noting that the molar surface Gibbs energy can be connected with the volume, density and surface tension. Therefore, it can be developed as a semi-empirical method to predict physical properties of substances like the parachor. In terms of the molar surface Gibbs energy, a new linear Eötvös equation is obtained. Using this new equation, the values of the molar surface enthalpy for aqueous [C_6mim][OAc] and other aqueous ILs were calculated. The results show that in the solution of the given molality, the molar surface enthalpy is a temperature-independent constant.
[en] In this paper, we apply the binary Bell polynomial approach to high-dimensional variable-coefficient nonlinear evolution equations. Taking the generalized (2+1)-dimensional KdV equation with variable coefficients as an illustrative example, the bilinear formulism, the bilinear Bäcklund transformation and the Lax pair are obtained in a quick and natural manner. Moreover, the infinite conservation laws are also derived. (general)
[en] Graphical abstract: A new Eötvös equation, g = B_1(T_c − T), was obtained, where g is the molar surface Gibbs energy; B_1 = s is the molar surface entropy; the product of B_1 with critical temperature, T_c, is the molar surface enthalpy, h, which is a temperature-independent constant. - Highlights: • The new concept of molar surface Gibbs free energy, g, was proposed. • Using g, the traditional Eötvös equation was improved to be a new one. • An equation to predict surface tension of ILs is derived with refractive index and g. - Abstract: Two new amino acid ionic liquids (AAILs) [C_nmim][Thr] (n = 2, 4) (1-alkyl-3-methylimidazolium threonine salt) were prepared and characterized. The values of density, surface tension and refractive index of the ILs were measured at T = (288.15 to 328.15) K and the values of the molar surface Gibbs free energy, g, were calculated. Using the molar surface Gibbs free energy, the traditional Eötvös equation was improved to be a new Eötvös equation. It is found that the slope of the new Eötvös equation is the molar surface entropy of the ILs and the intercept is the molar surface enthalpy which is a temperature-independent constant. With the help of the refractive index and the molar surface Gibbs free energy, an equation to predict surface tension of the ILs was derived. Using this equation, predicted values of surface tension with the corresponding experimental ones are highly correlated and extremely similar. According to a new scale of polarity for ILs, the polarity of ionic liquids [C_nmim][Thr] (n = 2, 4) was estimated.
[en] The demand for ancillary service is expected to increase significantly in the future Great Britain (GB) electricity system due to high penetration of wind. In particular, the need for frequency response, required to deal with sudden frequency drops following a loss of generator, will increase because of the limited inertia capability of wind plants. This paper quantifies the requirements for primary frequency response and analyses the benefits of frequency response provision from demand-side response (DSR). The results show dramatic changes in frequency response requirements driven by high penetration of wind. Case studies carried out by using an advanced stochastic generation scheduling model suggest that the provision of frequency response from DSR could greatly reduce the system operation cost, wind curtailment, and carbon emissions in the future GB system characterized by high penetration of wind. Furthermore, the results demonstrate that the benefit of DSR shows significant diurnal and seasonal variation, whereas an even more rapid (instant) delivery of frequency response from DSR could provide significant additional value. Our studies also indicate that the competing technologies to DSR, namely battery storage, and more flexible generation could potentially reduce its value by up to 35%, still leaving significant room to deploy DSR as frequency response provider.