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Modern energy batteries are mainly used in pure electric vehicles. The stability of battery operation relies heavily on thermal management systems for which phase-change batteries have become an effective solution. In this study, we designed a battery thermal management system divided into two parts: a shaped phase-change material (PCM) module and a battery module. In the qualitative PCM module, polyethylene glycol was used to absorb heat, expanded graphite (EG) was used as the thermally conductive agent, and copper foam formed the support skeleton. The battery module comprised an 18650 lithium-ion battery with an enthalpy of 155 J/g. In our experiments, we applied PCMs to the battery modules and demonstrated the effectiveness of composite PCM (CPCM) in effectively lowering the temperature of both battery packs and minimizing the temperature discrepancies among individual batteries. At a gradually increasing discharge rate (1C/2C/3C), the battery's Tmax could be lowered and the temperature could be de creased at various positions. It was evident that the battery temperature could be effectively preserved using CPCM. The findings of this study lay a foundation for future research on battery thermal management. Finally, the copper foam and EG contributed significantly to the prevention of leakage. [ABSTRACT FROM AUTHOR]

[Display omitted] • First comprehensive overview on low temperature CO 2 methanation. • Overview on CO 2 methanation fundamentals, catalysts and reactor technologies. • Identified challenges and opportunities in each of the areas reviewed. • A critical process simulation result for low temperature CO 2 methanation. CO 2 utilization technologies can not only provide a pathway to reduce greenhouse gas emissions but may also enable renewable energy to be incorporated into important materials used in the society such as fuel and chemicals. Power to gas (PtG) technologies, especially Power to methane has been deemed as one of the promising pathways for the conversion of CO 2 into valuable gaseous fuel. Many reports have reviewed the academic literature related to CO 2 methanation. While the benefits of high temperature methanation for overall process efficiency are well understood, the potential for low-temperature methanation is less understood. In particular the opportunities that arise from coupling a low-temperature methanation process with low temperature hydrogen production technologies, such as PEM electrolysis, have received little attention. It is therefore considered valuable to provide a critical review of the state of the art of this technology at low temperature conditions for the interests of broader research community. In this paper we focus on the recent work around low temperature CO 2 methanation including reaction thermodynamics and kinetics, catalyst materials including supports and promoters, and suitable reactor technologies. We discuss each of these critical aspects of the technology and identify key challenges and opportunities for low temperature CO 2 methanation (methanation conducted at temperatures less than 300 °C). As part of this paper, we also present the results of an ASPEN Plus simulation study based on data available from the literature to highlight the potential energy efficiency gains of a low temperature methanation process. [ABSTRACT FROM AUTHOR]

• Various synthetic methods for metal sulfides are introduced and compared. • Performances, merits, and flaws of metal sulfides are summarized and commented. • Layered metal sulfides, MoS 2 , WS 2 and SnS 2 , are the most promising mercury sorbents. • Effects of gas ingredients on the performances of metal sulfides are summed up. • Mercury capture mechanisms for metal sulfides are outlined and discussed. Mercury is largely emitted into the atmosphere during fossil fuel combustion or gasification, which causes a long-term contamination problem and poses great threats to human health. Currently, novel metal sulfides have been extensively investigated in capturing gaseous mercury because of their intense Hg0 affinities, large mercury uptakes, and distinguished tolerance to sulfur dioxide. This article overviews the recent progress on elemental mercury capture by diverse metal sulfides, i.e., CuS, ZnS, pyrite-phase metal sulfides, layered metal sulfides, Bi 2 S 3 and In 2 S 3. CuS and ZnS show good performances in a narrow temperature range due to the poor thermal stability and the compact crystal structure, respectively. Bi 2 S 3 and In 2 S 3 are also active in Hg0 adsorption, however, their performances are still unsatisfactory. Most pyrite-phase metal sulfides show moderate Hg0 capture abilities likely due to their compact crystal structures. Loading pyrites onto carriers or creating S vacancies in pyrite lattices seem to be feasible pathways to improve their performances. MoS 2 and WS 2 attained via molten salt method significantly outperform the ones obtained via hydrothermal method at elevated temperatures due to the production of ample sulfur variances and chemisorbed oxygen. Incorporating heteroatoms and expanding the interlayer distance by ions intercalation are effective routes to further strengthen their performances probably due to promoted electron transfer and increased accessibility of active sites, respectively. [ABSTRACT FROM AUTHOR]

For a phase-change material (PCM) confined in a porous structure, the interfacial interactions between the PCM and the porous skeleton are the decisive factors in latent heat storage performance. In this work, a novel composite PCM based on hierarchically porous TiO 2 and n-octadecane was successfully synthesized. The porous TiO 2 was prepared by a soft-template method, and the composite PCM was fabricated by introducing n-octadecane under vacuum. Transmission electron microscope and X-ray diffraction (XRD) results revealed that the as-prepared supporting matrix was crystalline TiO 2 , and N 2 adsorption/desorption isotherms indicated that TiO 2 has a hierarchically porous structure. For composite PCMs, Fourier transform infrared spectroscopy and XRD spectra revealed that no chemical bonds were formed between n-octadecane and TiO 2. Scanning electron microscopy results showed abundant n-octadecane enclosed within the nanopores and closely bound on the surfaces of the hierarchically porous TiO 2 , as a result of capillary forces and interfacial tension. Porous TiO 2 exhibited high adsorption for n-octadecane (50 wt%), and the relative enthalpy of the composite PCM was as high as 85.8 J/g. Compared with pure n-octadecane, the thermal conductivity of the as-prepared composite PCMs (e.g., 50 wt% n-octadecane sample) was improved by 138% with the addition of porous TiO 2. After 800 melting/solidifying cycles, the composite PCMs exhibited excellent thermal reliability and high enthalpy. The influence of the TiO 2 pore structure on n-octadecane crystallization behavior is shown in the results. • Hierarchically porous TiO 2 nanomaterial provided an ideal skeleton. • A novel n-octadecane/hierarchically porous TiO 2 composite PCMs was synthesized. • The effect of the nanoporous structure on crystallization is demonstrated. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A 3-layer phase change material configuration was proposed. • A method for temperature selection of phase change material was proposed. • Novel hybrid phase change material wallboards were fabricated and characterized. Abstract Phase change materials are smart, feasible latent heat storage materials and have been incorporated into building materials to reduce energy demand and improve the thermal comfort of buildings. This study proposes a method for improving energy efficiency and thermal comfort in buildings (during both summers and winters) by developing a novel hybrid phase change material wallboard and a method to select the temperature of phase change material for different seasons (29 °C for summer, 18 °C for midseason, and 12 °C for winter). This type of hybrid phase change materials wallboard consists of three types of phase change materials with different phase-change temperatures that can be utilized efficiently in different seasons. The thermal performances of the hybrid phase change material wallboards (two combination modes: Mode1 and Mode2) were evaluated by a guarded hot plate method. The effective thermal conductivity (λ) and apparent specific heat (C p) of these wallboards were investigated. The interior temperature variations of the two types of phase change materials wallboards were compared during heating and cooling, and it could be concluded that the Mode2 hybrid phase change materials wallboard (where phase change material was incorporated into different gypsum wallboard layers) was more suitable for real applications. The goal of this study is to investigate an appropriate method to fabricate a new hybrid phase change materials wallboard for building energy savings over different seasons. [ABSTRACT FROM AUTHOR]

Highlights • A home-made apparatus was developed to measure the thermal characteristics of the PCM-contained wallboard. • The "analogous step method" was proposed to determine the enthalpy of the bulk PCM in gypsum. • Three methods of obtaining H(t) curves were compared and analyzed. Abstract Phase change materials (PCM) as a smart, feasible latent heat storage material has been utilized to reduce the energy demand and improve the thermal comfort of the buildings when incorporated into the building materials. Conventionally, the thermal behavior of the PCM mixed with the solid matrix (mortar or gypsum) is different with the bulk PCM. In this study, we designed an experimental apparatus to characterize the thermal performance of PCMs when they were utilized in their implementation state. Firstly, we investigated the effective thermal conductivity (λ) and the apparent specific heat (C p) of the PCM-contained wallboard and the common gypsum wallboard, which were dependent on the temperature variation. Dynamic method was used to determine the phase change temperature, and the phase change process of the PCMs-wallboard was studied. Then, an "analogous step method" was proposed to determine the H(t) curves of the PCMs-wallboard, and the results were compared with the dynamic method. Finally, three methods of obtaining H(t) curves were compared and analyzed. From the obtained results, it can be concluded that when adopting the dynamic method appropriate heating rate (according to real application scenario) is necessary. When selecting the analogous step method, reducing the temperature interval can increase the accuracy of the H(t) even though it takes a lot of time. Anyway, both ways are more suitable for real wallboard test, comparing with the theoretical calculation method. The goal of our work is to investigate an appropriate method to evaluate the conductivities, apparent heat capacities, H(t) curves, and the phase change temperature of PCM-contained wallboards in their real application. [ABSTRACT FROM AUTHOR]

Abstract A novel n-octadecane@PMMA/TiO 2 hybrid shell PCM was prepared through a facile emulsion method, then characterized and estimated for thermal energy storage. During the synthetic process, the emulsion was enhanced by modified TiO 2 particles to improve the stability and thermal conduction. The aggregation process can be performed by an eco-friendly and efficient way, which was carried out under ultraviolet radiation for 10 min at 35 °C. The prepared microencapsulated PCMs have excellent nuclear shell structure, and the surface of the shell covered with TiO 2 particles uniformly. The TGA and DSC analysis showed that the microencapsulated PCMs have excellent thermal stability, high enthalpy and small degree of supercooling, which were suitable for thermal energy release and retrieval. The encapsulation efficiency of the microcapsules reached 67.2% when the appropriate proportion of MMA/n-octadecane was 1:1, and the melting enthalpy was 179.9 J/g. We also studied the crystallization behavior by in situ XRD method, the results showed that the crystallization behavior was different comparing with the bulk n-octadecane and hybrid shell PCMs. During the crystallization process, surface crystallization phenomenon occurred on the interface, which existed between inner surface of the microcapsules and melted n-octadecane. Subsequently, two sequential exothermic peaks were formed, which was different with bulk n-octadecane (only one exothermic peaks). The work was not only to develop a method to prepare the organic-inorganic hybrid shell Micro-PCMs, but also to study the discipline of crystallization behavior between the bulk n-octadecane and hybrid shell PCMs. Highlights • N-octadecane@PMMA/TiO 2 PCM was prepared through a facile efficient method. • The phase change behavior of composite PCMs was investigated. • The microencapsulated PCM showed excellent thermal performance. [ABSTRACT FROM AUTHOR]

A novel poly (ethylene glycol)/ZSM-5 composite was fabricated by a simple way, and it was characterized and evaluated for heat energy storage. The composite PCMs was fabricated through introducing PEG to mesoporous pores of ZSM-5 assisted with a vacuum impregnation system. XRD and FTIR analysis results showed that there was no chemical reaction happened between PEG4000 and ZSM-5. DSC and TGA analysis results indicated that the as-prepared PCMs has outstanding latent heats and superb thermal stability. The latent heat of the as-prepared PCMs achieves to 76.37 J/g without any leakiness. Compare with pure PEG, the thermal conductivity of as-prepared PCMs was improved 200%, which means selecting ZSM-5 serve as the supporting material was an effective way to enhance the thermal conductivity. Exudation stability tests results showed that the doping of PEG can reach up 50 wt% without any leakage when the composite undergoing the melting process. According to the above analysis, the prepared composite with good thermal stability, high latent heats and excellent thermal conductivity is very suitable for heat energy storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoS 2 /SnO 2 composite adsorbent is facilely obtained via a molten salt method. • CoS 2 and SnO 2 exhibit a cooperative effect with respect to mercury capture. • SnO 2 addition can notably reinforce the Hg0 capture ability of cobalt disulfide. • NO and SO 2 negatively affect the Hg0 removal performance of CoS 2 /SnO 2. SnO 2 doped cobalt pyrite (CoS 2 /SnO 2) adsorbent is facilely prepared using a molten salt method and used to capture Hg0 capture in simulated flue gas. Bare CoS 2 and SnO 2 display relatively lower Hg0 adsorption ability. SnO 2 addition can evidently enhance the Hg0 capture ability of CoS 2 likely owing to the synergetic effect between CoS 2 and SnO 2. NO and SO 2 can negatively affect Hg0 capture processes due to competitive adsorption or side reaction. Co2+, S 2 2-, Sn4+ ions serve as the major adsorption sites for elemental mercury capture over CoS 2 /SnO 2. Chemisorbed oxygen may be participated in the mercury removale process. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel composition of PCMW was proposed for complex climates. • Energy-saving potential of PCM-based wallboard was investigated for different locations. • The thermal response of PCM-based wallboard in different climates was analyzed. The incorporation of phase-change material (PCM) into construction materials has been proposed to indirectly accomplish indoor thermal comfort and energy saving. To adapt to seasonal changes (e.g., hot summer and cold winter), a novel type of hybrid PCM-containing wallboard (including three different PCMs) was proposed with a wide phase-change temperature range and that can work in various climates. In this study, a small building equipped with a hybrid PCM wallboard was established to evaluate energy-saving performance using EnergyPlus. To compare different hybrid PCM wallboards, four building models were considered, including Mode 1, Mode 2, Mode 3, and gypsum wallboard (BASE). The building performance in terms of heating and cooling energy consumption over one year was investigated at seven locations in China to represent different climate zones. The results show that less heating and cooling energy was required for Mode 2 than for the other models. Further investigation of the Mode 2 PCM wallboard revealed that the location of the PCM layer also influenced the energy savings. The total energy requirements for Mode 2 were lower than those for BASE by 2.15%, 4.33 %, 1.77 %, 5.56 %, 7.65 %, 5.84 %, and 0.2% for Shanghai, Beijing, Kunming, Lanzhou, Xining, Harbin, and Hong Kong, respectively. We conclude that the hybrid PCM wallboard can effectively reduce the heat gain through the building envelope throughout the year, presenting a considerable advantage of using it in buildings located in Shanghai, which experiences a hot summer and cold winter. [ABSTRACT FROM AUTHOR]

A simplified approach for the fabrication of CuO/TiO 2 was demonstrated. In this study, low cost CuO/TiO 2 photocatalysts (CuO loading 0–15 wt.%) were prepared, characterized and evaluated for gas-phase Hg 0 oxidation. The obtained CuO/TiO 2 photocatalysts were used to remove gaseous elemental mercury under UV light and visible light (both xenon lamp and LED), respectively, and the optimum doping levels of CuO and optimum illumination conditions were determined. The results showed that the CuO/TiO 2 photocatalysts were highly efficient in oxidizing Hg 0 , reaching above 70% in all cases under UV light, peaking at 57.8% with 1.25 wt.% CuO under visible light and peaking at about 60% with 1.25 wt.% CuO under LED light. We have proposed that the probable mechanism by which CuO/TiO 2 photocatalysts removes gaseous elemental mercury is two-fold: the CuO not only prevents electrons and holes from recombining, but also narrows the band gap of TiO 2 . [ABSTRACT FROM AUTHOR]

Abstract: Silicon carbide is a useful material for the reactors in chemical processes. In recent years, microreactors have gained significant attentions due to the high demand for process miniaturization. As heat and mass-transfer are highly improved inside the gas flow channels in microreactors, any change on the surface of inner channels under heating becomes critical to the performance of microreactors. To investigate the surface changes of silicon carbide during the heat treatment, 6H-SiC coupons were processed in five different gases—Ar, N2, air, 0.9% O2 in Ar and 50% H2O in air—that are commonly encountered in high temperature chemical processes. While the formation of oxide film was found to be dependent on the partial pressure of oxidizing gas, surface decomposition was found from the treatment in nitrogen environment. Characterization of the SiC surface by Raman spectroscopy and SEM–EDX revealed that a graphitic layer has formed at the oxide film/SiC interface. Crystallinity of graphitic layer at the interface seemed to be dependent on the partial pressure of oxidizing gas, which was revealed by the relationship between G peak position and R(I D/I G). The intensity ratio of FTO(0)/FTO(2/6) bands showed that stacking faults on the surface of SiC coupons were reduced after heat treatment. [Copyright &y& Elsevier]

[Display omitted] • The different morphologies of BiOI and Bi modified Bi 4 O 5 I 2 catalysts were successfully synthesized by three methods. • The synergistic effect of oxygen vacancies and built-in electric field promotes the separation of photogenerated electron-holes. • The 3D Bi/Bi 4 O 5 I 2 microspheres with rich oxygen vacancies exhibits an excellent photocatalytic activity and durability. • Possible photo-induced charges transfer mechanism and photocatalytic reaction mechanism were proposed. A 3D hierarchical metallic Bi modified Bi 4 O 5 I 2 microspheres with rich oxygen vacancies (Vos) was successfully prepared via a one-pot solvothermal method. In this work, the different morphologies of BiOI and Bi modified Bi 4 O 5 I 2 were prepared by precipitation, hydrothermal and solvothermal methods. It was discovered that using the solvothermal method with ethylene glycol as the solvent could not only prepare microspheres Bi 4 O 5 I 2 with rich oxygen vacancies but also control the content of Bi by changing the reaction duration. The doping of metallic Bi created a built-in electric field between Bi and Bi 4 O 5 I 2 , which is helpful to improve the efficiency of carrier separation. Benefited from the synergistic effect of oxygen vacancies and built-in electric field, the as-prepared Bi/Bi 4 O 5 I 2 exhibits an excellent mercury removal efficiency, high-performance stability, and satisfactory sulfur resistance as well as nitric oxide resistance. Finally, the mechanism of catalytic oxidation reaction was proposed, photo-generated holes and superoxide radicals were predominant in the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Steam-CO2 reforming of biomass derived synthesis gas (bio-syngas) was investigated with regard to the steam concentration in the feed using Rh-loaded alumina foam monolith catalysts, which was also accompanied by thermodynamic equilibrium calculation. With 40 vol % steam addition, steam methane reforming and water gas shift reaction were prevailed at the temperature below 640 °C, above which methane dry reforming and reverse-water gas shift reaction were intensified. Substantial change of activation energy based on the methane conversion was observed at 640 °C, where the reaction seemed to be shifted from the kinetic controlled region to the mass transfer controlled region. At the reduced steam of 20 vol %, the increase in the gas velocity led to the increase in the contribution of steam reforming. Comparing to the absence of steam, the addition of steam (40 vol %) resulted in the increase in the production of H2 and CO2, which in turn increased the H2/CO ratio by 95% and decreased the CO/CO2 ratio by 60%. Rh-loaded alumina monolith was revealed to have a good stability in upgrading of the raw bio-syngas. [ABSTRACT FROM AUTHOR]

• The prospect and limitation of low-dimensional carbon for Hg0 removal are commented. • Bio-char, carbon nitride, and metal-organic framework are promising mercury sorbents. • The performances and mechanisms of diverse carbon-based sorbents are fully discussed. Mercury emission, derived from natural gas exploitation, metal sintering, coal gasification and combustion, gold mining, etc., has posed great threaten to the environment and human beings due to its volatility, mobility, toxicity, and bioaccumulation in ecosystem and food chains. Adsorption using carbon materials is regarded as one of the most promising techniques for mercury emission control due to its simple equipment, convenient operation, high removing efficacy, less secondary pollution, etc. This review comments the new research progress of elemental mercury capture by novel carbon-based sorbents in recent five years, particularly emerging carbon materials, such as bio-chars, graphene and graphene oxide, carbon nanotubes and nanofibers, carbon spheres, carbon aerogels, metal-organic frameworks, and graphitic carbon nitrides. The mercury removal performances and reaction mechanisms of diverse carbon-based sorbents along with their merits and drawbacks are fully discussed, which aims to strengthen the understanding of this emerging research topic and outline future research directions for the development of sustainable, recyclable, and cost-effective carbon-based mercury sorbents. [ABSTRACT FROM AUTHOR]

[Display omitted] • H 2 and CO 2 mixture essential for thermal MOF-derivation of Ru0/ZrO 2. • H 2 acts by breaking down the MOF framework and by reducing Ru atoms. • CO 2 acts as a mild oxidant promoting carbon removal. • In operando powder XRD elucidated phase transition from MOF into active catalyst. Carbon Capture, Utilisation and Storage (CCUS) technologies are utilised to minimise net CO 2 emissions and hence mitigate the impact of anthropogenic emissions on the global climate. One example of CO 2 utilisation is the production of carbon-neutral methane fuel via catalytic CO 2 reduction with H 2 (methanation). Thermal activation of a metal impregnated metal-organic framework (MOF), 1 wt%Ru/UiO-66 in the presence of H 2 and CO 2 provides in situ synthesis of a highly active methanation catalyst: H 2 promotes the formation of Ru0 nanoparticles, and CO 2 behaves as a mild oxidant to remove framework carbon and promote ZrO 2 crystallisation. The nature of the active MOF-derived Ru0/ZrO 2 catalyst was studied by PXRD, TEM, and XAS, and the evolution of the parent 1 wt%Ru/UiO-66 during thermal activation monitored in operando by synchrotron PXRD. The Ru impregnated Zr-based MOF collapses on heating in H 2 and CO 2 to form an amorphous C and Zr containing phase that subsequently crystallises as tetragonal (t-) ZrO 2 nanoparticles. These t-ZrO 2 nanoparticles undergo a subsequent phase transition to the more stable monoclinic (m-) ZrO 2 polymorph. In situ activation of Ru/UiO-66 generates a highly active catalyst for CO 2 methanation by transforming the MOF precursor into a (carbon-free) crystalline t-ZrO 2 support that stabilises highly dispersed metallic Ru nanoparticles. This insight may guide the rational design of future MOF-derived catalysts. [ABSTRACT FROM AUTHOR]

Recently, salt-assisted pyrolyzation has been deemed an emerging and efficient method for the preparation of biochars due to its facile operation as well as its good structural and chemical properties. In this work, biochars (MBCx) are prepared by heating bamboo powders in eutectic salts (Li2CO3 + K2CO3) at 500–600 °C in the air. Multiple technologies are employed to examine the physiochemical properties of bamboo biochars. Correlations between heating temperature and structural features and carbon dioxide uptakes of bamboo biochars have been investigated. The results show that heating temperature has a significant influence on the physicochemical properties of bamboo biochars. With the elevation of the heating temperature, the defect structures of bamboo biochars gradually ascend, especially when the heating temperature reaches 600 °C. MBCx biochars visibly exceed conventional bamboo biochar prepared via pyrolyzation in a nitrogen stream free of salt addition. Pyrolysis of bamboo in eutectic salts endows biochars with higher oxygen content and more carbon defects, which likely accounts for their better CO2 capture activities. [ABSTRACT FROM AUTHOR]

Sulfate-induced deterioration can reduce the service life of recycled aggregate concrete (RAC). To demonstrate the transport behavior of sulfate ions in RAC, a two-dimensional, six-phase numerical model of RAC is proposed in this study. Sulfate ion diffusion coefficients were defined for different phases [attached mortar, new mortar, interfacial transition zone (ITZ) between attached mortar and original aggregate, ITZ between the new mortar and original aggregate, and ITZ between the new mortar and attached mortar] of RAC. The effects of ITZ width and porosity on ion transport behavior in RAC were analyzed. The results show that the numerical model agrees with the experimental data. Numerical results indicate that the six-phase model of RAC provides more-accurate simulation results because tortuosity is reflected in the model. The width and porosity of ITZs both affect the diffusion of sulfate ions in concrete. However, due to the low volume fraction of ITZ in concrete, just improving ITZ performance has no significant effect on ion attack resistance of concrete. The ITZ is a crucial zone where damage may originate and develop. [ABSTRACT FROM AUTHOR]

One of the most significant axes of regional, national, and worldwide energy policy is energy efficiency in building design. In particular, the energy efficiency of HVAC systems is of paramount importance. They provide energy for both residential and commercial sectors. As a result, assessing building energy usage is a critical step in optimizing building energy consumption. The impact of eight input factors on the two output variables, heating and cooling loads, for residential structures was explored in this study. For this purpose, the SVR-supervised machine learning algorithm was used. Despite its advantages, such as predictive accuracy and robustness, this method suffers from the fact that there is no specific rule for fitting its parameters. Therefore, six meta-heuristic optimization algorithms were investigated, and the strongest algorithm for optimal parameter fitting for the SVR model was presented. The correlation and error parameters analysis showed that the hybrid model SVR-AEO has the best performance in simulating residential buildings' heating and cooling loads. According to the obtained results, the value of R2 for the cooling and heating loads prediction in the training data is obtained to be 0.9975 and 0.99955, respectively. [Display omitted] • A hybrid Support Vector Regression model is presented to forecast building energy consumption. • The parameter selection for the SVR models is done by six different metaheuristic algorithms. • SVR-AEO simulates the heating and cooling loads of residential structures more accurately than others. • In 240 iterations, the SVR-AEO has the best MSE values in heating and cooling load. [ABSTRACT FROM AUTHOR]

The carbon modified BiOI/BiOIO 3 (CSs-BiOI/BiOIO 3 ) composites with heterostructures have been prepared via a facile hydrothermal method, using carbon spheres, bismuth nitrate and potassium iodate as precursors. Moreover, a new synthesis mechanism has been proposed. The photocatalytic activities of as-prepared catalysts are evaluated by oxidation of gaseous elemental mercury under visible light irradiation. It is found that the CSs-BiOI/BiOIO 3 exhibits highly enhanced visible photocatalytic activity, compared with that of pure BiOIO 3 . The results show that the Hg 0 removal efficiency of CSs-BiOI/BiOIO 3 reach up to 92.9% and 83.0% under LED light irradiation and simulated sunlight irradiation respectively. The improved photocatalytic activity can be ascribed to the increased the absorption of visible light, enhanced charge separation and transfer and the surface properties. This work points to CSs-BiOI/BiOIO 3 nanocomposites as new and efficient visible light photocatalysts for environmental remediation applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon nitride microsphere (CNS) is synthesized via a hydrothermal method. • Heterojunction interface between CNS and CeO 2 activate Hg0 adsorption process. • DFT guided design of microstructure is used to construct efficient mercury sorbents. • Hg0 is chemically adsorbed on the heterojunction interface of CeO 2 /CNS sorbent. Engineering sorbent microstructure to regulate their interfacial activity is a promising strategy for enhancing mercury adsorption activity. In this work, carbon nitride microsphere (CNS) synthesized via a hydrothermal route is used for Hg0 adsorption. Bare CNS shows a moderate Hg0 capture performance with mercury removal efficiency of 43.1%. To accomplish effective mercury capture by CNS, the heterojunction structure is rationally developed via density functional theory (DFT). Calculation results reveal a considerable charge interaction at the heterojunction interface of CNS and CeO 2. Mercury adsorption energy at the heterojunction interface is significantly higher than that of pristine CNS. x CeO 2 /CNS composites are prepared by wetness impregnation method under the guidance of DFT results. Optimal performance is observed over 5CeO 2 /CNS with Hg0 removal efficiency of 98.3%, which testifies that constructing a heterojunction interface can distinctly enhance the mercury capture ability of CNS. These results contribute a lot to the deep understanding of the structural properties and mercury adsorption behaviors of x CeO 2 /CNS composites, which also indicate that DFT-assisted design of the microstructures of sorbents is a feasible way to improve their mercury removal performances. [ABSTRACT FROM AUTHOR]

A simple and general approach is reported for the direct growth of carbon nanotubes (CNTs) on macroscopic carbon substrates. Two typical geometries of biomass materials, cellulose fibers or rice husks, are chosen to act as the precursor of carbon substrates, and commercial polypropylene (PP) pellets are used as the carbon source of CNTs with the presence of Ni-Mo-Mg catalysts. This simple and general strategy was realized by a direct pyrolyzation of the PP blends containing biomass materials and Ni-Mo-Mg catalysts in a chemical vapor deposition device at 800 °C under nitrogen's protection. The carbon products were characterized by various techniques such as X-ray diffractometer, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, and thermogravimetric analysis. Results show that the CNTs are successfully grown on the macroscopic carbon substrate derived from cellulose fibers or rice husks, whereas the addition of biomass materials as carbon precursors has to some extent an influence on the morphology of CNTs in the carbon products. [ABSTRACT FROM AUTHOR]

• Build a co-optimization model to optimize supply and demand sides of IES. • Modify stochastic programming to capture both demand and supply sides' scenarios. • Co-optimization model achieves more cost-efficient design considering carbon tax. • Basic and Standard demand-side upgrading are cost-efficient while Premium is not. • Carbon tax accelerates both renewable penetration and demand-side upgrading. Integrated energy systems (IES) can help achieve greater energy efficiency, and then ultimately promote a climate-neutral economy by utilizing local renewable resources. Demand-side energy-saving measures can reduce operational costs associated with energy usage. Most existing IES models, however, focus on supply-side optimization, while the demand-side energy-saving potential and its impacts on whole-system performance are still not clear. The increasing carbon tax makes it even more important to understand the interactions between supply and demand sides to achieve a sustainable system with a minimal carbon charge. Hence, this study proposes a co-optimization model to simultaneously optimize the supply and demand sides of an IES considering the impact of the carbon tax. A selection tree is developed to describe various demand-side envelope upgrading technologies, and a binary tree is established by generating a set of supply-side scenarios with corresponding probabilities. Based on these results, an improved two-stage stochastic programming model is proposed. The robustness of the modeling results was further validated by a simulation–optimization-based uncertainty analysis addressing price uncertainties. A case study in Shanghai indicates that the proposed co-optimization model achieves more cost-efficient solutions than supply-side-only optimization considering carbon tax. Introducing carbon tax can reduce the installed capacity of fuel-based energy technologies by up to 24% and greatly accelerate the penetration of renewables. The increasing carbon tax also promotes the adoption of more advanced energy-saving technologies. Uncertainty analysis reveals acceptable robustness of the optimal demand-side scheme and supply-side configuration with a deviation of less than 5% and a coefficient of variation of 7%. Overall, the observations of the proposed model and case study provide valuable insights for IES design considering an emerging charge of carbon tax. [ABSTRACT FROM AUTHOR]

• Model community-level energy by combining GIS, simulation, and data-driven approaches. • Propose a GIS-based urban building energy modeling method with low computational cost. • Generate various prototype buildings through two-stage clustering process to describe buildings' diversity. • Integrate urban building energy modeling with global sensitivity analysis to discovery urban planning factors. • Identify FAR and BCR as the most influential factors affecting communities' energy use. The residential sector accounts for an increasing amount of global energy use with continued urbanization. Residential energy-informed urban planning offers an economical and easy-to-operate approach to achieve more efficient urban energy utilization. However, quantifying the interactions between residential energy and urban planning remains an open challenge. This study proposes a holistic approach integrating GIS techniques, building energy modeling, and a global sensitivity analysis to prioritize eight key urban planning factors on the community energy performance based on a building energy dataset. The dataset, including urban planning and building information, was first established using GIS techniques and validated using survey data. The residential energy performance model at the community scale was developed using the clustering tree structure of residential building prototypes and building performance simulations. A combined data-driven and global sensitivity analysis approach was further applied to prioritize the impacts of eight vital urban planning factors on energy use intensity and peak load intensity. A case study of 1963 communities in Shanghai revealed that, for the energy performance of residential communities, the floor area ratio and building coverage ratio are the most influential factors, followed by the maximum height and high-rise proportion having a relatively low impact but higher than other factors. Overall, the proposed holistic approach generates robust insights into urban-scale residential energy performance, which can effectively inform urban planners to achieve more energy-efficient regulatory planning. [ABSTRACT FROM AUTHOR]

Various algorithms predominantly use data-driven methods for forecasting building electricity consumption. Among them, algorithms that use deep learning methods and, long and short-term memory (LSTM) have shown strong prediction accuracy in numerous fields. However, the LSTM algorithm still has certain limitations, e.g., the accuracy of forecasting the building air conditioning power consumption was not very high. To explore ways of improving the prediction accuracy, this study selects a high-rise office building in Shanghai to predict the air conditioning power consumption and lighting power consumption, respectively and discusses the influence of weather parameters and schedule parameters on the prediction accuracy. The results demonstrate that using the LSTM algorithm to accurately predict the electricity consumption of air conditioners is more challenging than predicting lighting electricity consumption. To improve the prediction accuracy of air conditioning power consumption, two parameters, relative humidity, and scheduling, must be added to the prediction model. [ABSTRACT FROM AUTHOR]

Human thermoregulation models can predict human thermal responses to evaluate thermal comfort and help create a healthy environment, while their applicability to older people has not been sufficiently validated. This study aimed to evaluate the performance of the Stolwijk model and the Tanabe model for predicting older people's mean and local skin temperatures under thermal transient conditions. Eighteen healthy older people were recruited and exposed to transient environments including neutral (26 °C), low-temperature (23 and 21 °C), and high-temperature (29 and 32 °C) conditions. The local skin temperatures of the subjects were measured and compared to predictions of the Stolwijk model and the Tanabe model. The results revealed that the Stolwijk model and the Tanabe model could accurately predict the mean skin temperature of older people under neutral and high-temperature conditions, while their predictive accuracy declined under low-temperature conditions. Increased deviations were observed in the predictions of local skin temperatures for all conditions. This work attempted to provide an understanding of older people's thermal response characteristics under transient conditions and to inspire the improvement of thermoregulation models for older people. [ABSTRACT FROM AUTHOR]

Uncertainty complicates the optimization model of distributed energy systems, it is a challenge to address the fragility of optimal solutions, which calls for an effective but convenient approach to introduce uncertainties into multi-objective optimization. This study proposes and compares the priori and the posteriori modeling approaches for optimizing the design of distributed energy systems under uncertainty. The posteriori approach is developed as a Monte Carlo simulation combined with the deterministic programming model, while the priori approach is formulated as a two-stage stochastic programming model. Both approaches consider economic and environmental objectives and use the same set of uncertainty parameters based on a case study in Shanghai. The results show that, compared with the priori-approach model, the posteriori-approach model leads to an underestimation of the total annual cost, but their total annual carbon emission approximates. Besides, the Pareto frontier cliques from the posteriori approach demonstrate the distributions of system performance, whereas the priori approach can capture the uncertainties at the substantially higher computational cost. Finally, the tradeoff between model complexity and computational cost is discussed to generate more insights on the optimal design, i.e., configuration and dispatch, of distributed energy systems. • Develop a multi-objective stochastic optimization model for distributed energy system • Quantify multiple uncertainties throughout the optimum stochastic scenarios • Combine Monte Carlo simulation and multi-objective deterministic optimization • Propose Pareto frontier cliques to exhibit the optimal solution regions • Comparatively analyze the priori and posteriori uncertainty-modeling approaches [ABSTRACT FROM AUTHOR]

• Propose a multi-objective optimization and robustness analysis integrated framework. • Merge multi-objective optimization with two-stage stochastic programming. • Generate probabilistic stochastic scenarios capturing multiple uncertainties. • Identify the final optimum solutions by two decision-making methods. • Combine optimization with Monte Carlo simulation for robustness analysis. The optimal design of building integrated energy system is sensitive to the variation of uncertain parameters. For addressing the tradeoff of uncertainty and optimality-robustness, this study proposes a combined multi-objective optimization and robustness analysis framework for optimal design of building integrated energy system. The proposed framework includes two parts. In the optimization part, on the basis of scenario generation for capturing the uncertainties of renewable energy sources and energy demands, two-stage multi-objective stochastic mixed-integer nonlinear programming is conducted to optimize the system's economic and environmental objectives. Two decision-making methods are introduced to identify the final optimum solution from the obtained Pareto frontier. In the robustness-analysis part, a combined Monte Carlo simulation and optimization method is implemented to verify the robustness of the optimal solutions. The two parts of the framework are integrated to investigate the case of a hotel in Beijing, China. The results indicate that compared with the stochastic model, the deterministic model underestimates the annual total cost. Achieving economic and environmental optimum is conflicting and needs a trade-off through decision making. Moreover, in the robustness analysis, an acceptable robustness value is identified, considering both the selected objectives and the operation constraints' probability of failure. The Shannon-entropy-based final optimum solution exhibits the best comprehensive performance, with an annual total cost of $695 × 103/year, an annual carbon emissions of 2100 tons/year, and an 8.81% probability of failure. [ABSTRACT FROM AUTHOR]

The analysis of energy configuration in the planning of data-center-park-integrated energy systems (DCP-IESs) has become an enormous challenge, owing to multi-energy complementarity, energy cascade use, and energy security. In this study, a configuration model of DCP-IESs was established to obtain the economic and low-carbon energy uses of the data centers, based on mixed integer linear programming. In the model, carbon emissions were converted to economic indicators through carbon pricing. Then, the configuration model was modified according to the security of the proposed device switching logic, and the Markov-based reliability estimation method was used to ensure the redundant design of the configuration. Using the new energy configuration method, the DCP-IES configuration scheme could be obtained under economical, low-carbon, and high reliability conditions. A data center park in Shanghai was selected as a case study, and the results are as follows: it will only take 2.88 years for the economics of DCP-IES to reach those of traditional data center energy systems. Additionally, the use of configuration model in DCP-IES would result in a reduction in annual carbon emissions of 39,323 tons, with a power usage effectiveness of 1.388, whereas an increase in reliability results in an increasingly faster increase in the initial investment cost. [ABSTRACT FROM AUTHOR]