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The possibility to increase human comfort and reduce the global footprint of buildings is a powerful driving force for introduction of new building technology. Here advanced coating technologies pl ...

A better understanding of the genetics of seedling characteristics in rice could be helpful in improving rice varieties. Zhenshan 97 and Minghui 63, the parents of Shanyou 63, an elite hybrid developed during the last decade in China, vary greatly with respect to their physiological and morphological traits at the seedling growth stage. In this study, we used a population of 240 recombinant inbred lines derived from a cross between Zhenshan 97 and Minghui 63 to identify quantitative trait loci (QTL) for seedling characteristics. All plant material was grown in hydroponic culture. Data for the following characters were collected at 30 days and 40 days post-sowing: plant height, shoot dry matter weight (SDW), maximum root length, root dry weight (RDW), total dry weight, and root-shoot ratio (the ratio of SDW to RDW). Analysis using composite interval mapping detected 16 QTL for the six traits in 30-day-old seedlings. Of these 16 QTL, Minghui 63 alleles increased trait values at only two of them. The QTL in the vicinity of R3166 on chromosome 5 simultaneously influenced PH, SDW, MRL, RDW, and TDW in the same direction. Twenty QTL were detected for the same traits in the 40-day-old seedlings. However, at this stage Minghui 63 alleles increased trait values at eight QTL. The QTL linked to R3166 also affected PH, SDW, MRL, RDW, and TDW. Only four QTL were common to the two stages. These results clearly indicate that different genes (QTL) control the same traits during different time intervals. Zhenshan 97 alleles had positive effects during the first 30 days of seedling growth, but thereafter the positive effects of Minghui 63 alleles on seedling growth gradually became more pronounced.

When the weak forces producing parity-violating effects are taken into account, there is a tiny energy difference between the total electronic energies of two enantiomers (ΔEPV), which might be the key to understanding the evolution of the biological homochirality. We focus on the electronic chirality measure (ECM), a powerful descriptor based on the electronic charge density, for quantifying the chirality degree of a molecule, in a representative set of chiral molecules, together with their EPV energies. Our results show a novel, strong, and positive correlation between ΔEPV and ECM, supporting a subtle interplay between the weak forces acting within the nuclei of a given molecule and its chirality. These findings suggest that experimental investigations for molecular parity violation detection should consider molecules with ECM values as large as possible and may support that a chiral signature is imprinted on life by fundamental physics via the parity-violating weak interactions.

Combined floating offshore wind turbines (FOWTs), wave energy converters (WECs), and floating solar photovoltaics (FPVs) systems have the potential to provide cost-effective solutions for offshore multi -energy complementation and structure protection. In this study, a theoretical model based on the potential flow theory and eigenfunction matching method is utilized to study wave diffraction and radiation by a co -located system, in which the main components of the wind platform and WECs are made of vertical cylindrical floats. Based on the displacement constraint matrix, coupled equations of motion are developed to calculate the kinematic response of the co -located systems. After running the convergence analysis and model validation, the present model is employed to perform a multiparameter impact analysis. Case studies are presented to clarify the effects of the WEC radius, draft, layout, power take -off (PTO) system, and incident wave heading and frequency on the hydrodynamic coefficient, wave energy capture width, and motion response of the wind platform. Our findings highlight that several factors play a crucial role in the performance of the co -located system, more importantly, that the theoretical model developed in this study is capable of effectively predicting the wave -structure interactions in wave fields, making it applicable to future wave farm projects.

Abstract The rapid development of distributed generation in different forms and capacities is transforming the conventional planning of distribution networks. Despite the benefits offered by renewable distributed generation technologies, several economic and technical challenges can result from the inappropriate integration of distributed generation in existing distribution networks. Therefore, the optimal planning of distributed generation is of paramount importance to ensure that the performance of distribution network can meet the expected power quality, voltage stability, power loss reduction, reliability and profitability. In this paper, we firstly discuss several conventional and metaheuristic methodologies to address the optimal distributed generation planning problem. Metaheuristic algorithms are often used as they offer more flexibility, particularly for multi-objective planning problems without the pursuit of globally optimized solution. Analytical techniques are considered suitable for modeling power system mechanisms and validating numerical methods. Then, this paper conducts a comprehensive review and critical discussion of state-of-the-art analytical techniques for optimal planning of renewable distributed generation. The analytical techniques are discussed in detail in six categories, i.e. exact loss formula, loss sensitivity factor, branch current loss formula, branch power flow loss formula, equivalent current injection and phasor feeder current injection. In addition, a comparative analysis of analytical techniques is presented to show their suitability for distributed generation planning in terms of various optimization criteria. Finally, we present conclusive remarks along with a set of recommendations and future challenges for optimal planning of distributed generation in modern power distribution networks.

Revealing the trends and main drivers of rural energy transition has important implications for building up a clean, efficient and sustainable energy system. Based on physical energy consumption, we measure the effective energy consumption and constructed a provincial panel dataset of rural China from 1990 to 2017. The results show that the energy transition is not only reflected in the growth of fuel consumption and the change of fuel structure, especially the growth of high-quality energy, the diversification of service functions and the convenience of use. The term of effective energy can more accurately measure the level of energy consumption per capita than physical energy. The income per capita, urbanization level and annual average temperature are three main factors impacting energy consumption. Every 1,000 yuan growth in per capita income can increase the consumption of 6 kgce physical energy and 4 kgce effective energy, respectively. Every 1% rise in the urbanization rate of the population can bring a growth of 4.86 kgce physical energy and 1.83 kgce effective energy. 1℃ of rise in average temperature may decrease by 22.3 kgce physical energy and 2.8 kgce effective energy. There are roughly-three levels of transition, the slow transition in the northeast, the forefront transition in the eastern coastal areas and the intermediate level transition in vast central and western regions. According to regional differences, focus should be on increasing the share of renewable energy, improving energy infrastructure and energy efficiency in the future.

Abstract The United Nations declaration of the Decade of Education for Sustainable Development (UN DESD, 2004–2014) advocates the need for universities to embed sustainability in all learning areas. This inquiry examines how selected post-graduate top-level programmes in urban studies are adapting their curricula to promote sustainable urban development. We start by reviewing an extensive literature to identify the principles and practices characterising the UN DESD, and to identify the topics and themes considered essential for teaching aimed at the promotion of sustainable urban development. Based on the extensive literature review we define an analytical framework in five parts, related to various aspects of curricular content and teaching and learning approaches: programme orientation, skills, ethics and critical reasoning, interdisciplinarity and content related to sustainable urban development issues. We then conduct an empirical study of 25 among the best post-graduate level (MA and MSc) programmes in urban studies from Europe, China, the USA and the Global South, to see how they are adapting their curricula to the requirements of sustainable urban development captured in the analytical framework. While acknowledging the significant context specificities that must be respected, and the multiple challenges that must be reconciled when defining urban studies curricula - we find both strengths and weaknesses in these top programmes, including important differences among the programmes from the four regions. Our data suggests that important steps are being taken towards ‘whole-system’ transformation envisaged by the UN Decade of Education for Sustainable Development, but also that transformative factors depending on cultural and institutional values and practices remain relatively weak.

Tools and experience on solar thermal cooling system sizing and design are still limited, as less than one thousand plants have been built until now. In this paper, a design tool for mid-size thermal solar cooling systems is presented. The tool consists of a model realised in TRNSYS and validated using the data of a real solar air conditioning system installed in the green building of Shanghai Research Institute of Building Science. Characteristic features of the system are the use of adsorption chillers driven by low-temperature solar heat from U-type and heat pipe evacuated solar collectors. The model has subsequently been employed for a technical analysis: the most relevant parameters have been varied and figures of merit calculated. An energy analysis has been performed for 6 reference cities, differing for climates and latitudes, highlighting the possibility to use only renewable energy for cooling purposes. Eventually, the systems have been compared with reference ones. Comparison highlighted that considerable savings in primary energy and CO2 emissions can be achieved: 0.97 MWh per installed square meter of solar collectors and up to 22 tons of CO2 annually, thus indicating a great potential for increasing energy efficiency and reduce CO2 emissions.