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Reports on the defective anodic titanium dioxide (TiO 2) that harvests solar energy to perform photochemical reactions generating value-added chemicals and/or energy are scarce. In this study, we synthesize TiO 2 with two different morphologies (i.e., nanotube and compact layer) on a Ti substrate in a fluoride- and sulfide-containing electrolyte by using the electrochemical anodization method. The effect of high-temperature annealing on various TiO 2 structures and substrates in comparison with commercial TiO 2 nanoparticles coated on fluorine-doped tin oxide substrate under different gaseous environments (i.e., Ar, air, and O 2) is investigated herein by virtue of crystallinity, optoelectronic-physical properties, and photoelectrochemical performances. Unlike traditional TiO 2 nanoparticles, which are only active in ultraviolet illumination and with severe aggregation, the anodic TiO 2 nanotubes endow the effect of the oxygen vacancy and the self-doping of F− and S− ions upon annealing under the Ar environment, which is crucial to extending the photoresponse to the visible region. The gray anodic TiO 2 obtained through thermal annealing at 450 °C crystallizes in the anatase phase and maintains an intact surface morphology under different gaseous environments. The electron paramagnetic spectra are used to confirm the presence of Ti3+ or oxygen vacancy. The entrapment of the F− and S− ions within TiO 2 is determined by X-ray photoelectron spectroscopy and energy-dispersive spectroscopy introducing intrinsic defect states, which can resolve the bottlenecks in materials and encourages new paradigms beyond solar light-induced photocatalysis. [Display omitted] • Different morphologies of TiO 2 nanostructures are fabricated. • The TiO 2 nanostructure defect is controlled by annealing in gaseous environments. • Comparison of visible photoresponse according to different TiO 2 structures. [ABSTRACT FROM AUTHOR]

Pressure retarded osmosis (PRO) harnesses salinity gradient energy through the mixing of freshwater and saltwater, addressing the demand for sustainable energy sources. PRO typically utilizes river water or secondary wastewater as the feed solution, paired with seawater reverse osmosis (SWRO) brine as the draw solution. However, the limited availability of low-saline water presents a significant obstacle to energy generation. Therefore, the feasibility of a high-pressure PRO process utilizing seawater as the feed solution and hypersaline water as the draw solution was assessed to generate sustainable blue energy. Seawater has the potential to achieve the maximum extractable Gibbs-free energy through high-pressure PRO by maximizing the feed/draw ratio. The performance of the high-pressure PRO was theoretically evaluated, resulting in a tenfold increase in specific energy production compared to conventional SWRO-PRO due to the higher feed/draw ratio. However, high hydraulic pressure increased the membrane structural parameter and further reduced water flux and power density due to significant internal concentration polarization. Nevertheless, the high-pressure PRO process can achieve a power density exceeding 84 W/m2 when the structural parameter remains below 100 μm. The implications of the high-pressure PRO were further discussed to advance the concept of a blue circular economy, enhance environmental resilience, and promote sustainability. [Display omitted] • Feasibility of high-pressure PRO was investigated using seawater/hypersaline water. • Higher feed/draw ratio boosted energy production in the PRO process. • Seawater was assessed as a feed for high-pressure PRO for blue energy generation. • High-pressure operation raised the structural parameter reducing power density. • High-pressure PRO achieved >80 W/m2 at structural parameter <100 μm. [ABSTRACT FROM AUTHOR]

Membrane processes have attracted considerable attention in the field of water treatment because of their excellent compactness, convenient operation and management, and relatively low energy consumption. However, fouling is a significant technical challenge. Electrically conductive membrane (ECM) technology has recently emerged as a promising alternative owing to its novel and effective mechanisms and outstanding fouling control efficiency. However, because ECM technology is still in the early stages of research, its maturity is low, and fundamental research on the mechanism is insufficient. In this critical review, the mechanisms of the ECM for fouling control were systematically elucidated and categorized as electrochemical oxidation and reduction, electrostatic interactions, and electrolysis. Subsequently, an extensive and comprehensive literature survey of ECM applications was conducted. The current state of the application and performance of ECM technology was evaluated. The operation and modification strategies of ECM research are discussed based on an accurate understanding and evaluation of the fundamental mechanisms and level of actual application of ECM technology for fouling control. Consequently, topics for future academic research and practical applications of the ECM are proposed. [Display omitted] • Fundamental mechanisms of ECM for fouling control are described and categorized. • Performances of ECM application to membrane processes are analyzed. • Recent operation and modification strategies of ECM are discussed. • Future directions for ECM research and applications are proposed. [ABSTRACT FROM AUTHOR]

• Few studies have addressed the mental health of adults who were raised in single mother households during infancy and toddlerhood. • Accessible job training programs for single mothers and free provision of accessible and high-quality childcare services by the government should be focused on single mothers, particularly those who are pregnant or have children under the age of 5 years. • The intergenerational transmission of inequality between single mothers and their adult children can be addressed by providing more opportunities for well-paying stable jobs with flexible schedules to single mothers. Based on a longitudinal approach, this study explores the effect of single mothers' employment from pregnancy to their children's preschool years on their adult children's self-esteem and depression. The National Longitudinal Survey of Youth 1979 (NLSY79) and the National Longitudinal Survey of Youth 79 for Children and Young Adults (NLSY79 CY) were employed to pair mothers and their adult children. We used six NLSY79 CY waves from 2004 to 2014. A total of 2,596 single mother-headed household dyads were selected. Variables repeatedly measured at six points in time were tested using the Random Effects Model. Results show that single mothers' higher frequency of employment from pregnancy to when their children were four years old was significantly related to their children's self-esteem and depression at above the age of 18 years. Discussion. Providing more opportunities for single mothers to get a job is necessary to enhance their children's mental health over time. Accessible job training programs for single mothers and free provision of accessible and high-quality childcare services by the government should be focused on single mothers, particularly those who are pregnant or have children under the age of 5 years, for their children to positively develop self-esteem and reduce depression over time. The intergenerational transmission of inequality between single mothers and their adult children can be addressed by providing more opportunities for well-paying stable jobs with flexible schedules to single mothers, so they are better able to provide their children with time, support and resources. [ABSTRACT FROM AUTHOR]

The moisture- and salt water-induced degradation of asphalt concrete molecular systems was investigated via molecular dynamics simulations. To establish the microstructure-to-property relationship of asphalt concrete mixture under hygroscopic aging, water molecules and sodium chloride (NaCl) ionic solutes were uniformly distributed in the binder or concentrated at the interface. The mechanical properties of the binder were slightly degraded by moisture and NaCl solutes. The viscosity of the binder decreased with distributed water, whereas it increased as the content of NaCl solute in the salt water increased. Moreover, the NaCl solutes promoted the hygroscopic eigenstrain of the asphalt binder. The interfacial properties between the binder and aggregate were not noticeably affected when moisture and NaCl solutes were uniformly distributed in the binder. While the moisture penetration into the interface was thermodynamically spontaneous when the amount of water was sufficient, the NaCl solutes in the water hindered the diffusion of moisture into the interface. Nonetheless, salt water penetrated into the interface seriously reduced the interfacial adhesion and the cohesive law in mode I and mode II decohesion than pure water. The condensation of penetrated salt water and the associated peeling mechanism of the interface were discussed to clarify the hygroelastic damage mechanism of the asphalt concrete mixture. • Degradation of hygroscopically aged asphalt concrete mixture was studied. • Moisture and Salt water resulted in hygroscopic swelling and remarkable change in viscosity of AAA-1 binder. • Penetration of water molecules in asphalt mixture was thermodynamically spontaneous and degraded the interface. • Dissolved NaCl mitigated the penetration of salt water while seriously deteriorated the interface in asphalt mixture. • Hygroelastic properties of binder and interface essential to constitutive modelling of asphalt mixture were determined. [ABSTRACT FROM AUTHOR]

The performance of chemical mechanical polishing (CMP) was determined by the morphological characteristics of the abrasive particle. In this study, the shape of the aggregate of fumed silica was confirmed by a method of characterizing the morphology of the particles using transmission electron microscopy (TEM). Each aggregate was classified into four types—linear, branched, ellipsoidal, and spheroidal—and the shape distribution of a fumed-silica slurry was investigated with different specific surface areas. The CMP performance of fumed silica slurries at 90 m2/g with numerous linear-shaped aggregates and 400 m2/g with the highest portion of spheroidal aggregates were compared to that of colloidal silica slurry. A model for the effects of bumpy abrasives on CMP explained the reason for this result by using penetration depth and MRR with various numbers of contact bumps. Furthermore, a mixture of spherical and non-spherical abrasives in a ratio of 4:1 exhibited an improved CMP performance. Unlabelled Image • The material removal principle of differently shaped particles was analyzed. • A method for capturing a single aggregate in fumed silica slurry was introduced. • The shape distribution of particles differs depending on the specific surface area. • The polishing performance was enhanced by mixing abrasives of different shapes. [ABSTRACT FROM AUTHOR]

Steam methane reforming (SMR) is widely used in the hydrogen production industry; however, a significant amount of CO 2 is released during this process. Several efforts have been made to produce low-CO 2 hydrogen (blue hydrogen) via SMR; however, the proposed solutions are not applicable to small-scale plants. Therefore, this study proposes an on-site SMR process combined with a hollow fiber membrane module (HFMM) for CO 2 capture in small-scale plants. First, mathematical models for the on-site SMR process and HFMMs were developed, and their accuracy was validated with real-world data. Second, we designed and implemented the SMR–HFMM model based on different operating conditions and gas compositions at three potential CO 2 capture locations (dry syngas, PSA tail gas, and flue gas). The CO 2 capture performances at these three locations were compared using five performance indicators: stage cut, separation factor, CO 2 recovery rate, permeate composition, and retentate composition. Finally, to evaluate the integrated processes for each CO 2 capture location, feasible ranges of the number of HFMMs and the levelized cost of hydrogen (LCOH) were calculated. In the case of CO 2 captured in dry syngas, the number of HFMMs required to achieve a CO 2 purity of over 90% was calculated to be 10–25. Furthermore, despite additional HFMM installation, the LCOH was 0.8%–1.5% lower than that of the conventional on-site SMR process that is 7.07–7.13 USD/kgH 2. The proposed integrated SMR–HFMM process is a potential solution to the problem of CO 2 emissions in on-site SMR processes with a lower LCOH. Therefore, the findings of this study could be of significant importance in improving the environmental sustainability of hydrogen production in small-scale plants. [Display omitted] • Steam methane reforming (SMR) emits CO 2. • Conventional blue hydrogen production methods are not appropriate for on-site SMR plant. • Integration of on-site SMR with a hollow fiber membrane module (HFMM) for hydrogen production was proposed. • HFMM could capture CO 2 with high efficiency in a real on-site SMR plant. [ABSTRACT FROM AUTHOR]

Steam methane reforming (SMR) is widely used in the hydrogen production industry; however, a significant amount of CO 2 is released during this process. Several efforts have been made to produce low-CO 2 hydrogen (blue hydrogen) via SMR; however, the proposed solutions are not applicable to small-scale plants. Therefore, this study proposes an on-site SMR process combined with a hollow fiber membrane module (HFMM) for CO 2 capture in small-scale plants. First, mathematical models for the on-site SMR process and HFMMs were developed, and their accuracy was validated with real-world data. Second, we designed and implemented the SMR–HFMM model based on different operating conditions and gas compositions at three potential CO 2 capture locations (dry syngas, PSA tail gas, and flue gas). The CO 2 capture performances at these three locations were compared using five performance indicators: stage cut, separation factor, CO 2 recovery rate, permeate composition, and retentate composition. Finally, to evaluate the integrated processes for each CO 2 capture location, feasible ranges of the number of HFMMs and the levelized cost of hydrogen (LCOH) were calculated. In the case of CO 2 captured in dry syngas, the number of HFMMs required to achieve a CO 2 purity of over 90% was calculated to be 10–25. Furthermore, despite additional HFMM installation, the LCOH was 0.8%–1.5% lower than that of the conventional on-site SMR process that is 7.07–7.13 USD/kgH 2. The proposed integrated SMR–HFMM process is a potential solution to the problem of CO 2 emissions in on-site SMR processes with a lower LCOH. Therefore, the findings of this study could be of significant importance in improving the environmental sustainability of hydrogen production in small-scale plants. [Display omitted] • Steam methane reforming (SMR) emits CO 2. • Conventional blue hydrogen production methods are not appropriate for on-site SMR plant. • Integration of on-site SMR with a hollow fiber membrane module (HFMM) for hydrogen production was proposed. • HFMM could capture CO 2 with high efficiency in a real on-site SMR plant. [ABSTRACT FROM AUTHOR]

• Control of wettability through changes of surface structure for self-cleaning. • Change of surface structure via anodization in K 2 HPO 4 /glycerol electrolyte. • Surfaces obtained from K 2 HPO 4 /glycerol electrolyte have higher wettability than those obtained from typical electrolytes. The Al 3104 alloy is widely used in the industrial field for building exteriors, heat blockers, and aluminum cans. These products are often exposed to long-term pollution, resulting in economic loss due to corrosion and the removal of pollutants. To solve these problems, self-cleaning of metal surfaces has been actively studied. Self-cleaning can be achieved by modifying hydrophilic or hydrophobic treatments to control the surface energy and surface structure. In the present study, the surface structure was changed through anodization technique. We fabricated three different structures of the top surface: nanotubes, porous, and nanopetals. The various nanostructures exhibited differences in wettability. Under the optimum conditions, the aluminum oxide layer exhibited hydrophilicity, which is a significant advantage for self-cleaning. [ABSTRACT FROM AUTHOR]

In previous studies on the kinetic spraying of cermet (e.g., WC-Co and Cr 3 C 2 –NiCr) the fragmentation of kinetic sprayed cermet particles was a prerequisite for successful deposition. Therefore, the properties of the feedstock powder related to fragmentation are significantly critical factors. In this study, a commercial Cr 3 C 2 –25NiCr powder was mechanically milled to accumulate damage in the feedstock powder and reduce the fragmentation resistance of the cermet particles, then heat-treated to relieve the strain hardening effects on the metal part (NiCr). The effects of the mechanical milling and heat-treatment were evaluated using a nanoindentation test, a powder compression test and transmission electron microscope observation after which the deposition characteristics of three kinds of powders (as-received, milled, and milled + heat-treated) were compared. The Cr 3 C 2 –25NiCr powder was considerably weakened by mechanical milling. There was no recovery of the fracture toughness and phase transformation of the milled Cr 3 C 2 –25NiCr powder even after the heat-treatment. Consequently, the deposition state of the milled and heat-treated Cr 3 C 2 –25NiCr powder was considerably enhanced compared with the as-received powder. Thus, mechanical milling and post heat-treatment of the commercial Cr 3 C 2 –25NiCr powder seems to be effective at enhancing its deposition capability for the kinetic spray process. [ABSTRACT FROM AUTHOR]

An energy source transition is necessary to realize carbon neutrality, emphasizing the importance of a hydrogen economy. The transportation sector accounted for 27% of annual carbon emissions in 2019, highlighting the increasing importance of transitioning to hydrogen vehicles and establishing hydrogen refueling stations (HRSs). In particular, HRSs need to be prioritized for deploying hydrogen vehicles and developing hydrogen supply chains. Thus, research on HRS is important for achieving carbon neutrality in the transportation sector. In this study, we improved the efficiency and scaled up the capacity of an on-site HRS (based on steam methane reforming with a hydrogen production rate of 30 Nm3/h) in Seoul, Korea. This HRS was a prototype with low efficiency and capacity. Its efficiency was increased through thermodynamic analysis and heat exchanger network synthesis. Furthermore, the process was scaled up from 30 Nm3/h to 150 Nm3/h to meet future hydrogen demand. The results of exergy analysis indicated that the exergy destruction in the reforming reactor and heat exchanger accounted for 58.1% and 19.8%, respectively, of the total exergy destruction. Thus, the process was improved by modifying the heat exchanger network to reduce the exergy losses in these units. Consequently, the thermal and exergy efficiencies were increased from 75.7% to 78.6% and from 68.1% to 70.4%, respectively. The improved process was constructed and operated to demonstrate its performance. The operational and simulation data were similar, within the acceptable error ranges. This study provides guidelines for the design and installation of low-carbon on-site HRSs. [Display omitted] • The capacity of hydrogen refueling station (HRS) was expanded from 30 to 150 Nm3/h. • Efficiency of on-site HRS was improved through exergy analysis. • Simulation data was validated with real operation data of the implemented process. • The fuel consumption and CO 2 emission were reduced. • This study provides design and efficiency improvement guidelines for on-site HRSs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cryogenic CO 2 capture and storage (CCS) reduces power generation efficiency penalty. • Power consumption during natural gas liquefaction decreases by up to 67.17%. • Liquefied natural gas (LNG) supply chain with cryogenic CCS reduces energy waste. • Natural gas liquefaction and regasification are integrated based on cryogenic CCS. • The exergy efficiency in the LNG supply chain is increased from 18.18 to 46.39%. Natural gas combined cycle power plants generate substantial amounts of CO 2. Also, since natural gas is produced in limited sites, the liquefied natural gas (LNG) supply chain consumes considerable energy in transporting natural gas overwide. Herein, advanced natural gas liquefaction and regasification processes using an LNG supply chain with cryogenic CO 2 capture and storage (CCS) are proposed using Aspen Plus® V11. This solves three significant problems associated with conventional LNG supply chains. First, through the utilization of LNG cold energy, the cryogenic CCS process reduces the efficiency penalty of power generation from 14.34 to 4.45%. Second, solid CO 2 from cryogenic CCS is used as an additional cold source in the natural gas liquefaction process by conveying it to the liquefaction site via the returning LNG ship. As a result, the power consumption in the refrigerant cycle is reduced by up to 67.17% than single mixed refrigerant (SMR) process. Finally, the LNG supply chain with cryogenic CCS minimizes the sustained energy waste between the natural gas liquefaction and regasification stages owing to the geographical separation. LNG cold energy from the regasification stage is utilized in the form of solid CO 2 in the CCS and liquefaction stages. Consequently, the exergy efficiency in the overall LNG supply chain increases from 18.18 to 46.39%. The findings of this study can potentially provide environmentally friendly design guidelines for various LNG processes that use LNG cold energy in CCS and natural gas liquefaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxy-fuel combustion-based blue hydrogen production process. • Integrates fossil fuel-based hydrogen production and electrolysis processes. • Proposed processes are SMR + SOEC and SMR + PEMEC. • SMR + SOEC shows highest thermal efficiency (85.2%) and exergy efficiency (80.5%) • SMR + SOEC shows lowest levelized cost of hydrogen and life cycle GHG emissions. Blue hydrogen is gaining attention as an intermediate step toward achieving eco-friendly green hydrogen production. However, the general blue hydrogen production requires an energy-intensive process for carbon capture and storage, resulting in low process efficiency. Additionally, the hydrogen production processes, steam methane reforming (SMR) and electrolysis, emits waste heat and byproduct oxygen, respectively. To solve these problems, this study proposes an oxy-fuel combustion-based blue hydrogen production process that integrates fossil fuel-based hydrogen production and electrolysis processes. The proposed processes are SMR + SOEC and SMR + PEMEC, whereas SMR, solid oxide electrolysis cell (SOEC), and proton exchange membrane electrolysis cell (PEMEC) are also examined for comparison. In the proposed processes, the oxygen produced by the electrolyzer is utilized for oxy-fuel combustion in the SMR process, and the resulting flue gas containing CO 2 and H 2 O is condensed to easily separate CO 2. Additionally, the waste heat from the SMR process is recovered to heat the feed water for the electrolyzer, thereby maximizing the process efficiency. Techno-economic, sensitivity, and greenhouse gas (GHG) analyses were conducted to evaluate the efficiency and feasibility of the proposed processes. The results show that SMR + SOEC demonstrated the highest thermal efficiency (85.2%) and exergy efficiency (80.5%), exceeding the efficiency of the SMR process (78.4% and 70.4% for thermal and exergy efficiencies, respectively). Furthermore, the SMR + SOEC process showed the lowest levelized cost of hydrogen of 6.21 USD/kgH 2. Lastly, the SMR + SOEC demonstrated the lowest life cycle GHG emissions. In conclusion, the proposed SMR + SOEC process is expected to be a suitable technology for the transition from gray to green hydrogen. [ABSTRACT FROM AUTHOR]

[Display omitted] • BPA, BPS and BPAF were effectively degraded under UV-LED/chlorine reaction. • RCS contributed the most to the removal of BPs, followed by chlorination at pH 6–8. • Radical contribution was dependent on the functional groups and pK a values of BPs. • Chlorinated BPs were major byproducts and these were removed with further reaction. • Ecotoxicity during the removal of BPs under UV-LED/chlorine reaction decreased. We investigated the UV-LED/chlorine reaction for the degradation of bisphenol A (BPA) and its alternatives, bisphenol S (BPS) and bisphenol AF (BPAF) in water. Three bisphenols (BPs) were removed by the pseudo-first-order kinetics. BPA showed the highest removal compared to BPS and BPAF at pH 7 due to the electron-donating isopropyl group in BPA compared to electron-withdrawing sulfonyl and hexafluoro-isopropyl groups in BPS and BPAF, respectively. While the degradation of BPs during the UV-LED/chlorine reaction was contributed mainly by reactive chlorine species (RCS) at pH 6 to 8, and mainly by chlorination reaction at pH 9 due to the different functional groups and pK a values of BPs, and the status of chlorine depending on pHs. While humic acid suppressed the degradation of BPs, HCO 3 − ions generally increased the removal of BPs. Chlorinated BPs (Cl x BPs) were identified as major transformation products (TPs) in the UV-LED/chlorine reaction using LC-QTOF/MS analysis, and these Cl x BPs were effectively removed by further reaction. In addition, >15 minor TPs and three mineralization products (acetate, formate, and chloroform) were identified for each BP degradation. Defluorination (37% in 4 hr) was observed an as the mineralization pathway for BPAF, indicating that UV-LED/chlorine reaction can break the strong C-F bond on BPAF. We proposed the degradation pathways of three BPs based on the identified TPs and theoretical reactive sites calculated using the condensed Fukui function. The major pathways were sequential chlorine substitution, coupling reaction, and hydroxylation reaction. The ECOSAR assessment showed that the UV-LED/chlorine process is effective in lowering the ecotoxicities of BPs and their TPs. [ABSTRACT FROM AUTHOR]

Abstract A numerical simulator entitled TOUGH-UDEC is introduced for the analysis of coupled thermal-hydraulic-mechanical processes in fractured porous media. Two existing well-established codes, TOUGH2 and UDEC, are coupled to model multiphase fluid flows, heat transfers, and discontinuous deformations in fractured porous media by means of discrete fracture representation. TOUGH2 is widely used for the modeling of heat transfers and multiphase multicomponent fluid flows, and UDEC is a well-known distinct element code for rock mechanics. The two codes are solved sequentially, with coupling parameters passed to each equation at specific intervals. After solving thermal-hydraulic equations within the TOUGH2 code, pressure and temperature information is imported into the UDEC model. After solving the mechanical equation within the UDEC code the calculated fracture apertures are converted to the equivalent permeability and porosity values for a TOUGH2 flow analysis. The solution is calculated by iteratively following an explicit sequence for numerical efficiency. Verifications are presented to demonstrate the capabilities of the coupled TOUGH-UDEC simulator. Three application examples of (1) shear dilation due to increased pore pressure, (2) thermal stress and (3) CO 2 injection, show that the new simulator can be an effective tool for geoengineering applications involving shear activation of fractures and faults. Highlights • TOUGH2 and UDEC are linked to model coupled THM processes in fractured porous rock. • TOUGH-UDEC is verified by hydromechanical and thermomechanical verification cases. • TOUGH-UDEC is applied to two basic hydroshearing and thermoshearing models. • TOUGH-UDEC is applied to a large-scale CO 2 injection and leakage analysis. [ABSTRACT FROM AUTHOR]

Ceria-based abrasive is widely used in the oxide chemical mechanical polishing (CMP) process due to its high polishing performance. Ce3+ ions on the surface of ceria form a Ce–O–Si chemical bond with surface of the SiO 2 wafer, significantly affecting the material removal rate (MRR). In this study, the ceria surface was reduced by contact with hydrogen gas in a high temperature isothermal environment. Hydrogen gas forms surface hydroxyls on the ceria. Then, the generated hydroxyls form H 2 O and oxygen vacancies occur through the desorption of the H 2 O. The color of ceria changed to blue due to a change of the crystal structure by the reduction reaction. The reducing ability of hydrogen gas increased as the reduction temperature increased and the Ce3+ ion concentration increased by 12.7% under isothermal conditions at 1000 °C. The MRR of reduced ceria was improved by up to 37.7% compared to the original ceria. [Display omitted] • The ceria particles were reduced by hydrogen gas in a high temperature environment. • Oxygen vacancy was formed through hydrogen adsorption and H 2 O desorption processes. • Ce3+ ion concentration increased as the reduction temperature increases. • The oxide removal rate was significantly affected by Ce3+ ion concentration. [ABSTRACT FROM AUTHOR]

A sharp-interface level-set method is presented for simulating the growth and collapse of a compressible vapor bubble. The interface tracking method is extended to include the effects of bubble compressibility and liquid-vapor phase change by incorporating the ghost fluid method to efficiently implement the matching conditions of velocity, stress and temperature at the interface. The numerical results for one-dimensional compressible flows and spherical bubble growth show good agreement with the exact solutions. The level-set method is applied to investigate the effects of phase change, ambient temperature and wall on the compressible bubble growth and collapse. [ABSTRACT FROM AUTHOR]

[Display omitted] • An induction heating-based reactor for ammonia decomposition is developed. • The reactor produced an ammonia conversion of >90.0 % at 600 °C and 7 bar. • Proposed process achieves a 150 Nm3/h carbon-free green hydrogen production. • Exergy analysis indicated an exergy efficiency of 54.21% for the overall process. • The levelized cost of hydrogen (LCOH) was calculated to be 6.98 USD/kgH 2. This study presents an induction heating-based reactor for ammonia decomposition and to achieve a 150 Nm3/h carbon-free green hydrogen production process. The developed metallic monolith reactor acts by increasing the reactor temperature through an electromagnetic induction method using renewable-based electricity. As a result, hydrogen is produced without the generation of air pollutants such as CO 2 , which are formed via the conventional production pathway. Furthermore, techno-economic analysis was conducted based on exergy and economic analysis to evaluate the feasibility of the developed process. Experimentally, the proposed reactor showed an ammonia conversion of 90.0 % at 600 ℃ and 7 barg. Exergy analysis indicated that the total unused exergy accounted for 45.79 % of the total exergy input, giving an exergy efficiency of 54.21 % for the overall process. Furthermore, the CAPEX and OPEX values are calculated as 1,599,567 USD and 644,719 USD/y, respectively; therefore, the levelized cost of hydrogen (LCOH) was calculated to be 6.98 USD/kgH 2. This study also demonstrated that the LCOH varies with the ammonia feed price and the process capacity, and so it would be expected to decrease from 6.98 to 5.33 USD/kgH 2 as the hydrogen production capacity is increased from 150 to 500 Nm3/h. Overall, our results confirm the feasibility of carbon-free green hydrogen production on on-site hydrogen refueling stations, and they will be expected to advance the development of an environmental hydrogen economy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amine CCS process is an energy-intensive system, increasing efficiency penalty. • Cryogenic CCS process is proposed to reduce efficiency penalty of NGCC power plant. • LNG cold energy is utilized to capture and store CO 2 in the solid phase. • The efficiency penalty is reduced from 14.34% to 3.51%. This study proposes a novel cryogenic CO 2 capture and storage (CCS) process using liquefied natural gas (LNG) cold energy in a natural gas combined cycle (NGCC) power plant. This study makes two major contributions to the literature. First, the cryogenic solid-phase CCS process using LNG cold energy can effectively reduce the efficiency penalty in NGCC power plants by solving the fundamental problems associated with the conventional CCS process: energy-intensive thermal treatment of the monoethanolamine-based absorption process and significant power consumption for compressing CO 2 to 150 bar. Second, the cryogenic CCS process requires minimal equipment installation in the NGCC power plant by integrating LNG cold energy utilization and CO 2 capture processes. The proposed cryogenic CCS process reduces the efficiency penalty from 14.34 % to 3.51 %, with a 99.93 % CO 2 capture rate. We believe this study will provide a novel guideline for reducing the efficiency penalty by overcoming the challenges of the conventional CCS process. [ABSTRACT FROM AUTHOR]

Quantum dot nanocrystals have particular optical properties due to the quantum confinement effect and the surface effect. This study focuses on the effects of organic materials capping quantum dot on the emission properties of quantum dots. The quantum dots prepared by using 1-hexadecylamine in the synthesis show strong emission, while the quantum dots prepared by using tri-octylphosphine oxide exhibit a suppressed emission and an extra emission related with the surface energy traps. These organic materials cap the quantum dots and make the surface conditions of quantum dots different. TEM images and X-ray diffraction patterns reveal that 1-hexadecylamine constructs a layer on the surface of quantum dot during the synthesis and this surface passivation by a layer of 1-hexadecylamine reduces the surface energy traps. Differently from 1-hexadecylamine, tri-octylphosphine oxide dangles from the surface, which causes a poorly passivated surface. This generates the surface deep trap levels giving rise to a significant and broad emission in the lower energy regime. The optical mechanism is studied by measuring the emission spectra and the time-resolved spectra at various temperatures from 4 K to 300 K. [ABSTRACT FROM AUTHOR]

SnO 2 /ZnS nanocomposites of SnO 2 quantum dots (QDs)-deposited ZnS nanorods having highly enhanced photocatalytic activity and photostability have been fabricated via a facile two-step hydrazine-assisted hydrothermal process without involving any surface treatments. The photocatalytic activity of SnO 2 /ZnS nanocomposites with a Sn-to-Zn molar ratio (R Sn/Zn ) of 0.1 is 3 times higher than that of pristine ZnS nanorods and 17 times higher than that of commercial ZnS. The incorporation of SnO 2 QDs increases the photocatalytic efficiency of ZnS nanorods due to the following reasons: photogenerated charge carriers are readily separated owing to type II band configuration and direct contact at interfaces without having any linker molecules; active surface sites are increased to adsorb more dye molecules; the light absorption range is extended to the visible region, generating more charge carriers on the surfaces of heterojunction structures. The decay time, as well as the intensity, of the band-edge emission of SnO 2 /ZnS nanocomposites at 325 nm decreases progressively and rapidly with the increase of R Sn/Zn , indicating that fast electron transfer takes place from photoexcited ZnS nanorods to SnO 2 QDs. Thus, the higher photocatalytic degradation efficiencies of SnO 2 /ZnS nanocomposites are considered to result mainly from the increased separation rates of photogenerated charges. The photostability of SnO 2 /ZnS nanocomposites is also improved due to the protection and charge-separation effects of decorating SnO 2 QDs. Our prepared SnO 2 /ZnS nanocomposites are suggested to have great potential for photodegradation nanocatalysts in the field of waste-water treatment. [ABSTRACT FROM AUTHOR]

Various industrial activities generate highly acidic wastewaters, posing a particular concern due to their large volume, environmental impact, and limited disposal options. Nanofiltration (NF) has the potential to provide energy-, cost-, and space-effective solutions for wastewater treatment at industrial sites. However, conventional thin-film composite NF membranes degrade under acid exposures, largely limiting their applications in industrial wastewater treatment. Development of chemically robust NF membranes that are stable during operation with highly acidic feed streams has been a subject of active research and industrial interest. In this critical review, we first provide a comprehensive survey for the broad spectrum of industrial processes that yield acidic wastewaters. We then conduct in-depth analyses for short- and long-term rejection performances and stabilities of commercial NF membranes, especially under low solution pH conditions. Several key mechanisms responsible for the degradation of semi-aromatic polyamide networks by acid-catalyzed hydrolysis are discussed to highlight the limitation of commercially available NF membranes. Finally, we describe a wide variety of technical strategies to fabricate acid-resistant NF membranes, focusing on the key mechanism to enhance acid stability. We conclude by providing useful insights to guide the future directions for academic studies as well as industrial applications of acid-resistant NF membranes. [Display omitted] • Performances of NF/RO membranes under acidic conditions were analyzed. • Fundamental mechanisms of acid-catalyzed degradation were described. • Recent fabrication strategies for acid-resistance NF membranes were discussed. • Future directions for acid-resistance NF membrane applications were proposed. [ABSTRACT FROM AUTHOR]

Closed-form load distribution solutions for calculation of the loads exerted by the rolling elements on the outer raceway in cylindrical and spherical roller bearings under radial loading are proposed. The analytical solutions are derived from the non-conforming contact solution of Hertz and the conforming contact solution of Persson. The maximum pressures due to the maximum loads of the rolling elements calculated from the analytical solutions are within a few percents of the results from the corresponding two-dimensional and three-dimensional finite element analyses. A simple method to estimate the fatigue lives of bearings based on the analytical solutions is also presented for engineers to compare the fatigue performance of bearings with different designs. [ABSTRACT FROM AUTHOR]

In this study, a novel hollow fiber nanofiltration (HFNF) was investigated for treating real Cijengkol river water in Indonesia. Ultrafiltration (UF) pretreatment was performed to evaluate the effect of UF on the HFNF performance. The water quality of the raw water and permeate of the UF, HFNF, and UF-HFNF hybrid was first characterized. UF could remove only solids, while both nanofiltration (NF) and the UF-NF hybrid achieved a high removal efficiency for impurities in river water, meeting the standards for drinking water quality. However, severe organic fouling occurred in the HFNF membranes. To effectively control organic fouling, various cleaning methods were investigated, and then the analyses of gel permeation chromatography (GPC) and fluorescence excitation emission matrix (FEEM) were conducted on backwashing wastewater to identify the cleaning mechanism. First, hydraulic flushing and backwashing were evaluated, and both methods achieved higher than 90% efficiency particularly for high-molecular-weight organic foulants (>1000 Da). However, the cleaning efficiency decreased during long-term operation because of the low removal efficiency of low-molecular-weight (LMW) organics. Hence, chemically enhanced backwashing (CEBW) (i.e., 5 ppm and 10 ppm NaOCl) was employed to enhance the cleaning efficiency. The results showed that membrane fouling was easily controlled by CEBW with 95% removal efficiency. To reduce the usage of chemicals, CO 2 scouring, and CO 2 nucleation backwashing were also examined. CO 2 nucleation backwashing exhibited a better efficiency than CO 2 scouring because of the additional effect of CO 2 nucleation on the HFNF membrane surface. Interestingly, a relatively high removal efficiency for fulvic acid-like organic fouling was observed in both CEBW and CO 2 nucleation backwashing, whereas tryptophan and tyrosine-like proteins, soluble microbial products (SMPs), and humic-like organics were hardly removed by acidic condition (pH < 6.5) or high shear force, leading to a low cleaning efficiency of CO 2 nucleation backwashing. [Display omitted] • Indonesia river water was treated by novel hollow fiber nanofiltration membrane. • The dominant membrane fouling was due to low molecular weight organic fouling. • Periodical hydraulic backwashing and CO 2 scouring can replace pretreatment. • Hydraulic backwashing removes only high molecular weight organic foulants. • Chemical and CO 2 backwashing can remove low molecular weight organic fouling. [ABSTRACT FROM AUTHOR]

Organic solvent nanofiltration (OSN) often needs to be conducted under extreme conditions in the chemical and food industries. In this work, we fabricated polybenzimidazole (PBI)-based OSN membranes that possess excellent stability under strongly basic conditions at pH 13. Two crosslinked PBI membranes were prepared by treating pristine PBI membranes with two epoxy-containing crosslinkers. Various permeation and characterization tests were performed to investigate the resistance of the membranes to solvents and basic environments. Both crosslinked membranes displayed reasonable permeance in pure solvents at room temperature under 10 bar operating pressure, along with a sharp molecular discrimination performance in ethanol environments. The crosslinked PBI membranes were found to be stable and did not completely lose their separation properties at high pH, although the effective pore size of the membranes increased presumably due to swelling. The separation performance of the membranes was found to be reversible between filtrations of neutral and basic aqueous solutions. Therefore, our crosslinked PBI membranes, which display exceptional stability, hold great potential for applications in OSN under basic conditions. [Display omitted] • Polybenzimidazole (PBI) OSN membranes were fabricated using crosslinkers containing epoxy groups at both ends. • The OSN performance of PBI membrane was found to be controlled by the structures of the crosslinkers. • The crosslinked PBI membranes exhibited a sharp molecular separation performance in organic solvents. • The crosslinked PBI membranes showed an outstanding chemical resistance under strongly basic conditions. [ABSTRACT FROM AUTHOR]

Power-to-methane (PtM) coupled with renewables requires an energy buffer to ensure a steady and flexible operation. Liquid CO 2 energy storage (LCES) is an emerging energy storage concept with considerable round-trip efficiency (53.5%) and energy density (47.6 kWh/m3) and can be used as both an energy and material (i.e., CO 2) buffer in the PtM process. Integration of LCES with the PtM process realizes co-production of methane and electricity, supports peak shaving of the power grid, and enhances profitability via the sale of electricity at peak hours. This study aims to design, optimize, and comprehensively evaluate the techno-economic performance of the PtM-LCES process using a renewable power mix of solar and wind. A process scheduling model is formulated to understand the impacts of storage sizing and power allocation on the process performance. Then, artificial neural network-based surrogate optimization was performed to establish a cost-optimal design. Investigation at Kramer Junction, California, found that the production cost of methane was 161.6 €/MWh with an efficiency of 76.2% and a renewables penetration of 78.7%. This cost could be reduced by improving LCES's performance and considering electricity price arbitrage in areas with high electricity prices. The electricity price arbitrage and improvement of LCES's performance could lower the cost to 83.8 and ∼60 €/MWh, respectively. Moreover, zero or negative carbon emissions can be achieved if the renewables penetration can be increased to 91.5%. Results indicate that the PtM-LCES process is both energy efficient and economically viable, through which renewable methane can be cost-competitive with fossil natural gas. • Power-to-Methane coupled with renewables via liquid CO 2 energy storage. • Process flexible operation achieved by a bidirectional connection with the grid. • Energy- and cost-efficient production of methane in a continuous manner. • Costs of methane in different scenarios range from 60 to 161.6 €/MWh. [ABSTRACT FROM AUTHOR]

[Display omitted] • On-site hydrogen refueling stations require efficient catalysts/reactors. • Intrinsic kinetics of Ru catalysts were estimated using a parametric estimation. • New multistage (two- and three-stage) reactor designs were proposed. • Multistage reactors showed less temperature drop (better reactor stability). • Three-stage reactor can improve hydrogen production and conversion. In recent years, interest in the development of a hydrogen economy has increased, and the steam methane reforming (SMR) reaction, which yields so-called "gray" hydrogen, is expected to play a key role in hydrogen refueling stations (HRSs) in the interim before "green" hydrogen process is developed. For this purpose, compact and economical designs for small- to medium-scale SMR processes for HRSs are required. Herein, we investigated the intrinsic kinetics of a Ru-based catalyst using catalyst experiments and parametric estimation. In addition, reactor modelling was performed using a kinetic model with a special focus on multistage reactor configurations. The proposed reactor design showed an increase in the reactor energy supplied rate from 6.98 to 7.55 kW compared to the base case (single-stage reactor), and the conversion increased from 86.2% to 91.2%. Further, the drastic temperature drop owing to the strongly endothermic nature of the SMR reaction was reduced, and, thus, reactor stability was improved. The proposed novel design of a multistage reactor using a Ru-based catalyst will advance the development of the hydrogen economy. [ABSTRACT FROM AUTHOR]

Propiconazole (PRO) is a triazole fungicide that is frequently detected in the water. In this study, we investigated the kinetics and degradation mechanism of PRO during the UV photolysis and UV/H 2 O 2 processes. PRO was removed by the pseudo-first-order kinetics in both processes. The removal of PRO was enhanced by increasing H 2 O 2 concentration in the UV/H 2 O 2 process. The highest removal under neutral conditions, and lower removal of PRO were observed in acidic and alkaline pHs in the UV/H 2 O 2 process. The presence of natural water ingredients such as Cl−, NO 3 −, humic acid acted as radical scavengers, but HCO 3 − ion acted as both radical promoter and scavenger in the UV/H 2 O 2 process. The transformation products (TPs) of PRO during both processes were identified using LC-QTOF/MS. Four TPs ([M+H]+ = 238, 256, 306, and 324) were identified during UV photolysis, and six TPs ([M+H]+ = 238, 256, 306, 324, 356, and 358) were identified in the UV/H 2 O 2 process. Among the identified TPs, TP with [M+H]+ values of 356 and 358 were newly identified in the UV/H 2 O 2 process. In addition, ionic byproducts, such as Cl−, NO 3 −, formate (HCOO−), and acetate (CH 3 COO−), were newly identified, indicating that significant mineralization was achieved in the UV/H 2 O 2 process. Based on the identified TPs and ionic byproducts, the degradation mechanisms of PRO during two processes were proposed. The major reactions in both processes were ring cleavage and cyclization, and hydroxylation by OH radicals. The Microtox test with Vibrio fischeri showed that, while the toxicity of the reaction solution increased first, then gradually decreased during UV photolysis, the UV/H 2 O 2 process initially increased toxicity at 10 min due to the production of TPs, but toxicity was completely removed as the reaction progressed. The results obtained in this study imply that the UV/H 2 O 2 process is an effective treatment for eliminating PRO, its TPs, and the resulting toxicity in water. [Display omitted] • Degradation of propiconazole (PRO) in UV photolysis and UV/H 2 O 2 were examined. • The water components mostly acted as radical scavengers in the UV/H 2 O 2 reaction. • Six transformation products (TPs) of PRO during both processes were identified. • Ionic byproducts as mineralization were identified in the UV/H 2 O 2 process. • The degradation mechanisms of PRO during two processes were proposed. [ABSTRACT FROM AUTHOR]

• ∙ Researchers should pay more attention to single mother-headed households who may be at higher risk of the intergenerational transmission of inequity. • ∙ A new framework is necessary to understand intergenerational economic mobility between single mothers and their young adult children. • ∙ It is imperative to consider the role of educational attainment when examining intergenerational economic mobility between single mothers and their young adult children. This study examines the underlying pathway of intergenerational economic mobility within single mother-headed families by considering the mediating role of young adult children's educational attainment. The National Longitudinal Survey of Youth 1979 (NLSY79) and the National Longitudinal Survey of Youth 79 for Children and Young Adults (NLSY79 CY) were used to pair data from single mothers and their young adult children. A total of 3,139 single mother and young adult children pairs were chosen for analysis. Ordinary least squares and logistic regression analysis were employed to examine the mediation model. Single mothers' poverty status was negatively associated with both their young adult children's educational attainment and income. The young adult children's educational attainment was positively related to their income. Results showed a full mediation of the relationship between single mothers' poverty status and their young adult children's income via their young adult children's educational attainment. Researchers should pay more attention to single mother-headed households who may be at higher risk of the intergenerational transmission of inequity. A new framework is necessary to understand intergenerational economic mobility between single mothers and their young adult children. It is imperative to consider the role of educational attainment when examining intergenerational economic mobility between single mothers and their young adult children. [ABSTRACT FROM AUTHOR]

Numerical simulation is performed for stick-slip contact line motion and particle line formation in dip coating. The liquid–gas interface as well as the liquid–gas–solid contact line is tracked by a sharp-interface level-set method, which is extended to include the effect of phase change, to implement the contact angle model for the stick-slip contact line motion, and to treat the particle deposition on a moving substrate. The computations demonstrate that the particle line formation is directly related to the stick-slip contact line motion. The effects of initial particle concentration, substrate withdrawal velocity, substrate temperature and contact angle on the particle line formation in dip coating are investigated. [ABSTRACT FROM AUTHOR]

Methyl-functionalized mesoporous silica SBA-15, synthesized from tetraethyl-orthosilicate (TEOS) and methyltriethoxysilane (MTES), were employed as additives for the enhancement of volumetric mass transfer coefficient ( k L a ) of methane in aqueous solution. The surface functional group, highly ordered structure, and exceptionally high surface area exerted great influence on mass transfer rate of methane in aqueous solution. Especially, the fraction of surface functional groups controlled by adjusting the ratio of TEOS to MTES was found to be a crucial factor. Mesoporous characteristics of synthesized materials were investigated via BET surface area analysis, small angle X-ray diffraction, and FT-IR spectroscopy. At an optimal molar ratio (20:1) of TEOS and MTES, an 88% enhancement of k L a for methane in water was observed at 30 °C. [ABSTRACT FROM AUTHOR]

Numerical simulation is performed for liquid film formation and evaporation on a moving vertical plate, which occurs in dip coating. The liquid–gas interface is tracked by a sharp-interface level-set (LS) method, which is modified to include the effect of phase change at the interface. Numerical techniques for the liquid–gas–solid contact line on a moving plate and the conservation of particle concentration are incorporated into the LS method. The flow and thermal characteristics associated with the dip coating are investigated by solving the conservation equations of mass, momentum, energy, vapor mass fraction, and particle concentration. The effects of plate velocity and temperature on the dip coating process are investigated. [ABSTRACT FROM AUTHOR]

Poly(propylene carbonate) (PPC) is a plastic material that can be mass produced from naturally abundant carbon dioxide. This polymer is also known to decompose back to CO 2 when heated above about 200 °C. Here we report that the CO 2 -generation temperature of PPC can be reduced down to the 40–80 °C range in aqueous environment by using a photoacid generator (PAG) as the catalyst for activating the random scission reaction of PPC. We also investigated the thermal degradation of a PPC-based amphiphilic block copolymer, poly(poly(ethylene glycol) methyl ether methacrylate)-poly(propylene carbonate)-poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMA-PPC-PPEGMA). These triblock copolymers form stable small-sized (<200 nm) micelles in water. We found evidence that with the aid of added PAG these micelles can degrade under mild heating conditions (<80 °C), similarly to what is expected from PPC homopolymer experiments. The combined results suggest that PPC-based amphiphilic block copolymers might be of interest for applications in ultrasound contrast. [ABSTRACT FROM AUTHOR]

Theta-phase gamma-amplitude coupling (TGC) between slow and fast oscillations is considered to represent cortico-subcortical interactions. The purpose of this electroencephalographic (EEG) study was to evaluate the diagnostic utility of TGC by comparing the power spectra and TGC at rest between ADHD and control children. Nineteen-channel EEGs were recorded from 97 volunteers (including 53 subjects with ADHD attending a camp for hyperactive children). The EEG power spectra and TGC data were analyzed. Analysis of covariance (ANCOVA) was conducted on the quantitative EEG results between the groups to adjust for sex. Receiver operator characteristic (ROC) analysis was conducted to examine the discriminating ability of each parameter for ADHD diagnosis. The ADHD group exhibited significantly decreased TGC in multiple areas, including frontal (Fp1, F3, F7, F6), temporal (T3), and occipital (O2) areas, compared with the control group. The ROC analysis performed on the TGC data generated the most accurate result among the EEG measures, with an overall classification accuracy of 71.7%. TGC, which reflects the degree of neuronal interactions between functional systems, provides information about an individual's attentional network. Therefore, resting-state TGC is a promising neurophysiological marker of ADHD in children. [ABSTRACT FROM AUTHOR]

Currently, hydrogen is produced primarily through steam methane reforming, a gray hydrogen production process that generates CO 2 as a by-product. Thus, it is crucial to optimize the process thermal efficiency with minimizing CO 2 generation in a hydrogen production process. This study focuses on the multi-objective optimization of low-carbon hydrogen production process, considering both process thermal efficiency maximization and CO 2 emission minimization. To this end, a hybrid deep neural network model is developed to increase the robustness of the multi-objective optimization. The developed hybrid deep neural network model is incorporated into a proposed multi-objective particle swarm optimization algorithm that performs Pareto dominance-based multi-objective optimization. In experiments conducted, Pareto-optimal solutions with thermal efficiency distribution between 77.5 and 87.0% and CO 2 emissions between 577.9 and 597.6 t/y were obtained. Furthermore, the Pareto-optimal front was analyzed to provide various representative solutions to assist decision-makers. The findings of this study can enable efficient and flexible process operations according to various requirements. [Display omitted] • Low-carbon hydrogen production from an on-site steam methane reforming process. • Multi-objective optimization of thermal efficiency and CO 2 emission simultaneously. • Multi-objective particle swarm optimization for Pareto dominance-based optimization. [ABSTRACT FROM AUTHOR]

Ceria slurries are used in the oxide chemical mechanical polishing (CMP) process due to their high polishing performance and selectivity characteristics. However, it takes great effort to remove small ceria particles that remain on the wafer surface during the post-CMP cleaning process. Therefore, we applied tangential flow filtration (TFF) systems, which can be used to separate small ceria particles before CMP process. In a previous study, we improved the post-CMP cleaning efficiency of the ceria slurry with a circulation-type TFF system. Herein, the correlations between the separation rate of ceria particles and parameters affecting the TFF system, such as membrane pore size, flow rate, and transmembrane pressure (TMP), were evaluated to improve buff cleaning efficiency. Finally, we also fabricated a single-pass TFF system to reduce the process time and loss of active ceria particles. With the single-pass TFF system, the basic properties and polishing performance of the ceria slurry did not change. In addition, the buff cleaning efficiency improved by up to 18.1%. [Display omitted] • The TFF system was applied to improve buff cleaning by separating the small ceria particles (<50 nm) in the slurry. • The correlation between the separation rate and TFF system parameters was investigated. • The single-pass type TFF system was fabricated to shorten the process time and minimize the loss of active ceria particles. • With the single-pass type TFF system, the buff cleaning efficiency was improved and showed similar performance to SC-1. [ABSTRACT FROM AUTHOR]

The Continuous Performance Test (CPT) is a valuable tool for assessing behavior in attention-deficit/hyperactivity disorder (ADHD). Quantitative electroencephalography (QEEG) is a promising tool for the diagnosis of ADHD. Recently, theta-phase gamma-amplitude coupling (TGC) measurement has received attention because it is a feasible method of assessing brain function. We investigated the relationship between CPT performance and EEG measures such as TGC and theta and gamma activity. EEGs were recorded from 68 volunteers from a camp for hyperactive children using a 19-electrode system. Their TGC, theta and 40 Hz gamma activity were estimated and compared with results obtained on the Korean ADHD Rating Scale (KARS) and the Intermediate Visual and Auditory (IVA) CPT. The results demonstrated significant negative partial correlations between TGC and the IVA CPT, such as the Response Control Quotient (RCQ) and Attention Quotient (AQ). TGC successfully identified the level of dysfunctional interaction of the attention/arousal system at a multi-scale large network level. It is thought that as the TGC increases, the efficacy of the system is very low or dysfunctional. Compensatory hyper-arousal patterns of the dysfunctional attention/arousal system may account for this effect. TGC is a promising neurophysiological marker for ADHD behavior in children. [ABSTRACT FROM AUTHOR]

Precious metal-free electrocatalysts are essential for green hydrogen using low-cost electrolysis technology for future power supply systems. In this regard, anion-exchange membrane (AEM) electrolysis is the technology of best choice due to its compactness and high efficiency. Here, we proposed a low cost electrocatalyst composed of cadmium sulfide (CdS) nanoparticles decorated in a Cobalt-based metal-organic framework (CdS/ZIF-67), synthesized using a simple coprecipitation method. Compared with pristine Cobalt-based metal-organic framework (ZIF-67), 5 wt%CdS/ZIF-67 has excellent electrochemical oxygen evolution reaction activity, low overpotential (294 mV), low Tafel-slope (100 mV dec−1), higher mass activity (25.8 mA mg−1), and better stability. The AEM electrolyzer with the 5 wt%CdS/ZIF-67 anode can attain a potential of 1.85 V at a current-density of 1 A cm−2, which is lower than that of bare Cobalt-based metal-organic framework electrolyzers. Thus, these catalysts are not only very active but also scalable, making them a promising electrolyzer for application in commercial power market. [Display omitted] • CdS nanoparticle embedded in Cobalt-based metal-organic framework nanostructures. • The electrocatalytic OER activity of ZIF-67 was enhanced by CdS (5 wt%) nanoparticles. • 5 wt%CdS/ZIF-67 electrocatalysts showed a superior activity in AEM electrolyzer. • This noble metal-free nanocomposite has more efficiency and stability towards OER. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mesoporous SiO2-coated gold nanorods have been irradiated by a Xe lamp for 2h. [•] Irradiated nanocatalysts exhibit superior catalytic performances and reusability. [•] Improved catalytic activity is due to surface atom restructuring by light treatment. [Copyright &y& Elsevier]

Abstract: Objective: Many researchers have reported a relationship between Internet addiction and depression. In the present study, we compared the resting-state quantitative electroencephalography (QEEG) activity of treatment-seeking patients with comorbid Internet addiction and depression with those of treatment-seeking patients with Internet addiction without depression, and healthy controls to investigate the neurobiological markers that differentiate pure Internet addiction from Internet addiction with comorbid depression. Method: Thirty-five patients diagnosed with Internet addiction and 34 age-, sex-, and IQ-matched healthy controls were enrolled in this study. Patients with Internet addiction were divided into two groups according to the presence (N =18) or absence (N =17) of depression. Resting-state, eye-closed QEEG was recorded, and the absolute and relative power of the brain were analyzed. Results: The Internet addiction group without depression had decreased absolute delta and beta powers in all brain regions, whereas the Internet addiction group with depression had increased relative theta and decreased relative alpha power in all regions. These neurophysiological changes were not related to clinical variables. Conclusion: The current findings reflect differential resting-state QEEG patterns between both groups of participants with Internet addiction and healthy controls and also suggest that decreased absolute delta and beta powers are neurobiological markers of Internet addiction. [Copyright &y& Elsevier]

Highlights: [•] SiO2-coated Ag/Au nanoboxes were synthesized via galvanic replacement. [•] The nanoboxes catalyze the degradation of 4-nitrophenol efficiently. [•] The catalytic reaction occurs on the inner and the outer surfaces of the nanoboxes. [•] Catalytic performances were sustained after being recycled repeatedly. [ABSTRACT FROM AUTHOR]

Highlights: [•] The cross-frequency phase–amplitude coupling may be successfully adapted to the scalp resting EEG. [•] There are significant correlations between cross-frequency phase–amplitude couplings and the measures of risk-taking propensity. [•] It is suggested that the cross-frequency phase–amplitude coupling could be a promising indicator for diagnosing the tendency to take risks. [Copyright &y& Elsevier]

During chemical mechanical polishing (CMP) for a dielectric layer, Ce3+, which is the active site on the surface of ceria, has a significant effect on the material removal rate (MRR). Ceria nanoparticles were synthesized using a hydrothermal method with different dopant concentrations of lanthanide elements (La and Nd) to increase the concentration of Ce3+. An oxygen vacancy was formed in the ceria doped with the trivalent lanthanide ions, which reduced the surrounding Ce4+ to Ce3+. The concentration of Ce3+ increased up to 32.57% when the amounts of dopants were increased and Nd was doped. The improved reactivities of the particles by doping were verified by measuring the reduction of the work function of the doped ceria nanoparticles and the increase in the adhesion force with SiO 2. The polishing performance of Nd-doped ceria at high concentrations achieved an MRR up to 3.62 times higher than those of the comparison groups. [Display omitted] • Via facile hydrothermal method, lanthanide-doped ceria was massively synthesized. • The number of Ce3+ was increased by the formation of oxygen vacancies through doping. • The electrical potential of ceria was enhanced with an increase in the concentration of Ce3+. • The effect of Ce3+ on oxide polishing was discovered from their adhesive interaction. [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses thermally-induced shear slip, i.e., thermoshearing, and changes in permeability of a deep geological repository in large scale. We present a systematic examination of the thermal stress expected to be generated in the far-field around the repository. The main mechanisms for generation of thermal stress that can affect permeability are; comparatively high horizontal compressive thermal stress at the repository level, vertical tensile thermal stress right above the repository and horizontal tensile stress near the surface, and shear stress at the corners of the repository. Based on thermal loading history, probabilistic shear slip analysis was conducted to investigate the possibility of thermoshearing. Higher probability of shear slip is expected with higher differential thermal stress, and this was highly affected by fracture orientations. Stress paths obtained from the thermo-mechanical analysis were used as stress boundary conditions for Discrete Fracture Network-Discrete Element Method (DFN-DEM) Analysis to investigate the effect of stress changes on permeability. In four out of the six DFN models, normal deformation dominated the closure and opening of fractures, with shear dilation being the dominant factor in the other two models. Changes in permeability caused by shear dilation were not reversed after the repository cooled, which is explained by the irreversible fracture shear deformation after shear slip. This study was conducted on data from the Forsmark site in Sweden, and this analysis has implications for sites that have comparatively large horizontal in-situ stresses and relatively few fractures. [Copyright &y& Elsevier]

Abstract: It is important that the proportion of true null hypotheses be estimated accurately in a multiple hypothesis context. Current estimation methods, however, are not suitable for high-dimensional data such as microarray data. First, they do not consider the (strong) dependence between hypotheses (or genes), thereby resulting in inaccurate estimation. Second, the unknown distribution of false null hypotheses cannot be estimated properly by these methods. Third, the estimation is affected strongly by outliers. In this paper, we find out the optimal procedure for estimating the proportion of true null hypotheses under a (strong) dependence based on the Dirichlet process prior. In addition, by using the minimum Hellinger distance, the estimation should be robust to any model misspecification as well as to any outliers while maintaining efficiency. The results are confirmed by a simulation study, and the newly developed methodology is illustrated by a real microarray data. [Copyright &y& Elsevier]

Abstract: Alpha event-related desynchronization (ERD) and synchronization are known to reflect brain activation and inhibition, respectively. Alpha phase locking seems to reflect the timing in the cortical process. In a previous study, lower alpha ERD was related to working memory in obsessive-compulsive disorder (OCD) patients than in controls during the retention and retrival phases, but not in the encoding phase. However, memory deficits in OCD patients are known to be related to executive failure during the encoding phase. Thus, focusing on the encoding phase, we tested the level of alpha amplitude and phase locking in OCD patients according to memory load. The EEGs of fifteen OCD patients and fifteen controls were recorded during a Sternberg working memory task. The behavioral performance of the OCD patients was normal. However, the OCD group yielded significantly lower ERD and stronger phase locking. As memory load rose, ERD and phase locking significantly increased in both groups. A difference in event-related alpha oscillation was observed in the encoding phase. Lower alpha modulation in the OCD patient simplied abnormality of the excitatory/inhibitory process in the brain, and increased phase locking might reflect excessive attentional excitability. [Copyright &y& Elsevier]

Abstract: GaN-based light-emitting-diodes (LEDs) on (111) Si substrates with internal quantum efficiency (IQE) exceeding 50% have been successfully grown by metal organic vapor phase epitaxy (MOVPE). 3.5μm thick crack-free GaN epitaxial layers were grown on the Si substrates by the re-growth method on patterned templates. Series of step-graded Al x Ga1−x N epitaxial layers were used as the buffer layers to compensate thermal tensile stresses produced during the post-growth cooling process as well as to reduce the density of threading dislocations (TDs) generated due to the lattice mismatches between III-nitride layers and the silicon substrates. The light-emitting region consisted of 1.8μm thick n-GaN, 3 periods of InGaN/GaN superlattice, InGaN/GaN multiple quantum wells (MQWs) designed for a peak wavelength of about 455nm, an electron blocking layer (EBL), and p-GaN. The full-widths at half-maximum (FWHM) of (0002) and (10−12) ω-rocking curves of the GaN epitaxial layers were 410 and 560arcsec, respectively. Cross-sectional transmission electron microscopy (TEM) investigation revealed that the propagation of the threading dislocations was mostly limited to the interface between the last Al x Ga1−x N buffer and n-GaN layers. The density of the threading dislocations induced pits of n-GaN, as estimated by atomic force microscopy (AFM), was about 5.5×108 cm−2. Temperature dependent photoluminescence (PL) measurements with a relative intensity integration method were carried out to estimate the internal quantum efficiency (IQE) of the light-emitting structures grown on Si, which reached up to 55%. [Copyright &y& Elsevier]

Abstract: Failure mode of laser welds in lap-shear specimens of high strength low alloy (HSLA) steel sheets is investigated in this paper. The experiments for laser welds in lap-shear specimens under quasi-static loading conditions are briefly reviewed first. The experimental results showed that the laser welds failed in a ductile necking/shear failure mode and the ductile failure was initiated at a distance away from the crack tip near the boundary of the base metal and heat affected zone. In order to understand the failure mode of these welds, finite element analyses under plane strain conditions were conducted to identify the effects of the different plastic behaviors of the base metal, heat affected zone, and weld zone as well as the weld geometry on the ductile failure. The results of the reference finite element analysis based on the homogenous material model show that the failure mode is most likely to be a middle surface shear failure mode in the weld. The results of the finite element analysis based on the multi-zone non-homogeneous material models show that the higher effective stress–plastic strain curves of the weld and heat affected zones and the geometry of the weld protrusion result in the necking/shear failure mode in the load carrying sheet. The results of another finite element analysis based on the non-homogeneous material model and the Gurson yield function for porous materials indicate that the consideration of void nucleation and growth is necessary to identify the ductile failure initiation site that matches well with the experimental observations. Finally, the results of this investigation indicate that the failure mode of the welds should be examined carefully and the necking/shear failure mode needs to be considered for development of failure or separation criteria for welds under more complex loading conditions. [ABSTRACT FROM AUTHOR]

Abstract: Histone deacetylase (HDAC) inhibitors are a promising new class of anticancer agents that act by inhibiting cell proliferation and inducing apoptosis in a variety of cancer cells. Although apicidin acts as a potent HDAC inhibitor, the precise mechanism for its anti-tumor activity in human endometrial cancer cells is not completely understood. This study examined the anti-tumor effects of apicidin in Ishikawa cancer cells. The level of cell proliferation, the stage of the cell cycle, and apoptosis were measured after the apicidin treatment. Apicidin significantly inhibited the proliferation of Ishikawa cells in a dose-dependent manner. In addition, apicidin markedly up-regulated the p21WAF1 and down-regulated the expression of cyclins (A, B1, D1, or E), and CDKs (2 or 4), which leading to cell cycle arrest. Cell cycle analysis showed that the apicidin treatment increased the proportion of cells in the G1 phase, and decreased the ratio of cells in the S phase in a dose-dependent manner. Apicidin significantly increased the sub-G1 population and the number of TUNEL positive apoptotic cells compared with the untreated control. These results were confirmed by poly-ADP ribose polymerase (PARP), an 85-kDa fragment resulting from PARP cleavage, where apicidin increased the level of PARP cleavage and caspase-3 activity in 1.0μM apicidin-treated cells. Apicidin-induced apoptosis through caspase-3 activation was confirmed by the increase in the release of cytochrome c and the decrease in the Bax/Bcl-2 ratio. These results suggest that apicidin has anti-tumor properties on endometrial cancer cells by inducing selectively the genes related to cell cycle arrest and apoptosis. [Copyright &y& Elsevier]

Abstract: The mitochondrial adenine nucleotide translocators (Ant) are bi-functional proteins that transport ADP and ATP across the mitochondrial inner membrane, and regulate the mitochondrial permeability transition pore (mtPTP) which initiates apoptosis. The mouse has three Ant isoforms: Ant1 expressed in heart, muscle, and brain; Ant2 expressed in all tissues but muscle; and Ant4 expressed primarily in testis. Ant1-deficient mice manifest muscle and heart but not brain pathology. Brain Ant1 is induced by stress, while Ant2 is not. Ant1-deficient mice are resistant to death induced by systemic exposure to the brain excitotoxin, kainic acid (KA), and their hippocampal and cortical neurons are significantly more resistant to neuronal death induced by glutamate, KA, and etoposide. The mitochondrial membrane potential of Ant1-deficient brain mitochondria is increased and the mtPTP is more resistance to Ca++ induced permeability transition. Hence, Ant1-deficiency may protect the brain from excitotoxicity by desensitizing the mtPTP and by blocking the pro-apoptotic induction of Ant1 by stress. [Copyright &y& Elsevier]