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Since the renewable energy penetration in electricity system is getting more and more increased, new strategy is desired to help accommodate the fluctuated renewable energy. This paper proposes a transient-state gas flow model based unit commitment of integrated electricity and gas system (IEGS) with a decomposition optimization scheme adopted to satisfy the privacy protection requirements of system operators. The problem is solved decomposedly in an iteration procedure and the convergence of solution is guaranteed as well. Case study is conducted on a 6-bus 7-node system to verify the effectiveness of renewable energy accommodation capability. Besides, comparison between centralized optimization and the proposed decomposed optimization demonstrates that the adopted decomposition optimization scheme can find the global optimal integer variables, which further verify the validity of the proposed strategy.

Abstract Climate change and rapid adaption of invasive pathogens pose a constant pressure on the fruit industry to develop improved varieties. Aiming to accelerate the development of better-adapted cultivars, new breeding techniques have emerged as a promising alternative to meet the demand of a growing global population. Accelerated breeding, cisgenesis, and CRISPR/Cas genome editing hold significant potential for crop trait improvement and have proven to be useful in several plant species. This review focuses on the successful application of these technologies in fruit trees to confer pathogen resistance and tolerance to abiotic stress and improve quality traits. In addition, we review the optimization and diversification of CRISPR/Cas genome editing tools applied to fruit trees, such as multiplexing, CRISPR/Cas-mediated base editing and site-specific recombination systems. Advances in protoplast regeneration and delivery techniques, including the use of nanoparticles and viral-derived replicons, are described for the obtention of exogenous DNA-free fruit tree species. The regulatory landscape and broader social acceptability for cisgenesis and CRISPR/Cas genome editing are also discussed. Altogether, this review provides an overview of the versatility of applications for fruit crop improvement, as well as current challenges that deserve attention for further optimization and potential implementation of new breeding techniques.

Super-hot rock geothermal is an emerging source of renewable and carbon-free energy. This paper is the first attempt to explore fluid and heat flow dynamics in the reservoir-wellbore coupled system, to assess the power generation performance of a super-hot (>450 °C) enhanced geothermal system (EGS). We developed a high-performance code and built a 3-D wellbore-reservoir coupled model based on data from a recently completed deep-drilling project at Larderello, Italy. The general pattern of the super-hot EGS is characterized by a significant temperature plummet (>60 °C), after which the production fluid evolves from steam to a two-phase mixture till the end of the operation period. Reservoir pressure emerges as a key parameter to determine the temperature of the two-phase mixture. By realistically capturing phase transitions driven by coupled thermo-hydraulic processes during operations, our numerical model predicts a lower power generation efficiency compared to previous attempts based on ultra-simplified models. Although finalized at assessing the thermodynamic viability of a specific system, this modeling approach provides general information on fundamental thermo-hydraulic processes in the Earth crust that might be applied for the design of similar EGS projects elsewhere.

Electrolysis occupies a dominant position in the long-term application of hydrogen energy, as it can use the power surplus directly from renewable energies to produce hydrogen. Alkaline water electrolysis (AWE) is a mature and reliable technology standing out from other types of electrolysis because of its simplicity and low cost. Several multiphysics processes inside the AWE cell, such as the electrochemical, thermal, and fluidic processes. Developing the multiphysics model to quantify the relationship between these physics fields is essential for cell design. This paper establishes a three-dimensional numerical model to consider the quantitative relationship between the electrochemical process and fluidic process inside the cell of industrial AWE. The model considers the structural design of industrial AWE equipment, revealing that the shunting current effect introduced by the structure design cannot be ignored in the model. The simulation results present that the multiphysics model considering the bubble effect can estimate the current–voltage (I-V) characteristic curve more accurately with a relative error smaller than 5%, especially at a current density higher than 2500 A/m2. The model established is supposed to advance the development of water electrolysis models and guide the electrolyzer design of industrial AWE cell.

Abstract Organic farming is considered as a promising solution for reducing the environmental burden related to agricultural practices. China is one of the top-five countries with the largest organic area in the world and produces a major part of the world's organic rice. Rice cultivation causes a considerable environmental impact and changing from conventional to organic rice cultivation might therefore have a potentially great impact. Meanwhile, it takes time for the organic farming systems to reach a new steady state after conversion to organic. Thus, the environmental profile of the organic products will change over time and it is therefore important to examine whether the difference to conventional will be reduced (and disappear) or be increased over time. The aim of the present study was therefore to assess the environmental impact of organic rice production 5 (OR5), 10 (OR10) and 15 (OR15) years since conversion and compare it to conventional rice (CR) in subtropical China. The life cycle assessment (LCA) method was used to assess environmental impact of rice production systems with regard to nine environmental impact categories: Non-renewable Energy Depletion (NED), Water Depletion (WD), Land Occupation (LO), Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP), Aquatic Toxicity Potential (ATP), Human Toxicity Potential (HTP) and Soil Toxicity Potential (STP). Overall, the results show that the conventional rice production system had the highest comprehensive environmental impact indices (9.65), more than 10 times that of the organic ones. Interestingly, the results showed that the environmental impact indices in the organic rice systems decreased over time from 0.80 (OR5), 0.72 (OR10) to 0.68 (OR15), and thus increased the difference to conventional over the years. The conventional rice had higher impacts from NED, WD, AP, EP, ATP, and HTP, while organic rice had higher LO, GWP and STP indices. The largest environmental index was ATP for conventional and WD for organic rice. Based on this study, organic rice systems have the potential of being recommended as sustainable agricultural practices in comparison with conventional practices. Furthermore, the present study indicated that the difference in the environmental profile of organic versus conventional agricultural products might be underestimated when analyzing organic system that has not yet reached their steady state.

The Urban Intelligence (UI) paradigm conceived by CNR consists of an ecosystem of digital technologies joined within a Digital Twin (DT) of the city aimed at improving the city governance towards goals addressed also by the UN Agenda 2030, such as urban environment, sustainability and resilience, wellbeing and quality of life, local development, and social inclusion. In particular, UI provides a set of candidate policies in complex scenarios, and supports policy makers and stakeholders in designing shared, evidence-based, and integrated solutions. UI is being applied for the first time to two Italian cities, Matera and Catania, paving the way for a deeper scientific framing of the paradigm, as well as for the technological development and testing of the core UI ecosystem in real-life situations. The paper introduces the UI key-concepts and components, illustrates the ongoing experimentations in these pilot cities related to the development of two DTs on parts of the urban areas, and presents some initial results.

Monitoring of anaerobic digestion process is essential for achieving efficient and stable performance, thus requiring identification of effective stability indicators. The response of two experimental, continuously stirred tank reactors under mesophilic condition (fed with pig manure) was investigated to analyze the perturbation of organic and hydraulic overloading, and low-temperature shock. The pH was stably maintained in the range of 7.2-7.7, regardless of the presence of most simulated perturbation situations. Monitoring of biogas production and composition is important to reflect the current state of biogas process, but cannot predict the imbalance in the system. Accumulation of total VFAs up to 21,718 mg/L was observed under the organic overloading condition (rapid increase of the organic loading rate of pig manure from 3 g VS/L/d to 9 g VS/L/d), but not for other perturbations. The ratio of propionate to acetate and that of intermediate alkalinity to partial alkalinity are rapidly altered in response to all perturbations, indicating their potential to function as stability indicators. However, the determination of the ratio of intermediate alkalinity to partial alkalinity can be performed by simple titration methods and be easily applied to actual projects without significant investment in advanced equipment and skilled operators.