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China's residential buildings in cold and severe cold regions grapple with unaddressed summer overheating issues owing to the lack of tailored regional standards, necessitating a critical examination through globally recognized thermal comfort benchmarks. In this study, 27 bedrooms and 47 living rooms in 13 representative cities were monitored from May to September in the years 2021–2023 to investigate the summer indoor operative temperature of residential buildings in 5 sub-regions. The accuracy of adaptive models from ASHRAE 55, EN 16798–1, and GB/T 50785 for overheating evaluations was tested using measured data. Further, the Chinese Thermal Comfort Database (CTCD) was expanded in this study to enable the development of a preliminary Summer Residential Adaptive Model (SRAM) specifically designed by considering the distinct characteristics of China's cold and severe cold regions. Analysis of the monitoring results showed that 73.1 % of living rooms and all bedrooms were overheated according to CIBSE TM59. Moreover, the slope of SRAM is 0.40, which is lower than 0.73–0.77 of GB/T 50785 and higher than 0.31 and 0.33 of ASHRAE 55 and EN 16798–1, respectively. Further comparative assessments revealed inconsistencies with actual human sensations of heat. The results of this study highlight the inadequacy of CIBSE TM59 and existing thermal comfort standards in accurately assessing building overheating in China's cold and severe cold regions. To improve evaluation, future research must integrate regional climate modeling, various architectural configurations, and thermal sensation indicators to refine the developed SRAM, thus enabling the establishment of more holistic thermal comfort standards. • Highlights standard gaps in cold climates by documenting widespread residential overheating across 74 rooms in 13 Chinese cities. • Refines an adaptive model (slope 0.40) using 21 thermal comfort datasets from 5 sub-regions. • Exposes CIBSE TM59 and standard thermal comfort models' limitations in evaluating overheating accurately. [ABSTRACT FROM AUTHOR]

• Self-tapping screws restored the rotational capacity of connections with cracks. • Partially threaded screws showed a trend to effectively control crack propagation. • A theoretical prediction method is demonstrated. This study uses partially threaded self-tapping screws to enhance the mechanical properties of damaged and undamaged dowel-type timber connections. The damaged connections have a 1.5 mm wide artificial crack across the middle row of the fasteners. Test results showed that screw reinforcement can restore the rotation capacity of damaged connections. The rotational capacity of reinforced connections without cracks is 45.6% higher than unreinforced connections while the improvement on moment-resisting capacity is slight. Digital image correlation (DIC) was used to detect the movement of the connections and validated that the fasteners rotate around the centre of rotation in reinforced connections. Screw reinforcement also demonstrated the ability to control crack propagation, with the reinforced groups showed a reduction of crack length by at least 37% when compared to the unreinforced groups. A calculation method is proposed to calculate the characteristic moment-resisting capacity of damaged and undamaged screw reinforced connections. The calculated values are proven to be conservative when compared with the characteristic value based on the experimental results. [ABSTRACT FROM AUTHOR]

Highlights • Full-scale testing on timber portal frame with screw reinforcement. • Innovative use of self-tapping screws. • Qualitative discussion on the effectiveness of screw reinforcement. Abstract In this study, partially threaded self-tapping screws have been used as reinforcement on timber portal frames to enhance mechanical performance of dowel-type connections. Experimental tests on unreinforced and reinforced portal frames showed that reinforced frames achieved a 31% and 51% increase in moment-resisting capacity and ultimate rotation, respectively. The test on the reinforced frames was stopped when the stroke on the hydraulic jacks had been reached, while 20% of load drop was not observed. The test results demonstrated the performance of partially threaded self-tapping screws which reduces the drive-in torque when compared to fully threaded self-tapping screws. A theoretical prediction on the characteristic moment-resisting capacity of screw reinforced portal frames is proposed. [ABSTRACT FROM AUTHOR]

Given the forecasts of global warming and heatwaves, concern is growing about the exacerbation of overheating in dwellings in severe cold and cold regions of China. This concern, however, has been neglected by Chinese national building codes and standards. The focus in these regions has been to preserve heat during winter, lacking in definite measures prescribed for heat protection during summer. Although many studies have examined the situations in Europe, limited effort has been devoted to investigating overheating in China. The aim of this research is to use validated simulation results and empirical data to reveal overheating risk in these regions of China and identify deficiencies in local standards. The indoor temperature of residential buildings in four representative cities (Yichun, Harbin, Shenyang and Dalian) was measured from May to September 2021. To extend the observation period and enhance the reliability of the results, this study carried out building performance simulations using typical weather data over 15 years (2004–2018). Having the models validated, the results revealed the severity of overheating phenomenon. During the summertime (May to September), overheating were recorded for 6, 191, 483 and 578 h out of total 3672 h (accounted for 0.4%, 12.4%, 31.6% and 37.6%) in the south-facing bedrooms of Yichun, Harbin, Shenyang and Dalian respectively. It is therefore suggested that the design standards should consider a trade-off between thermal retention in winter and overheating in summer. The findings provide useful information and guidance for policymakers contemplating low-carbon building schemes and regulations on thermal comfort. • Vast territory measurements in newly-built stocking of severe cold and cold regions in China. • Simulation applied with local-recorded weather files of 2021, validated against monitoring results. • Simulation applied with TMY weather files over a recent 15-year period, revealing typical overheating performance. • Suggestions for modification of building regulations in the regions. [ABSTRACT FROM AUTHOR]

Abstract: Three novel terpolymers, i.e. P-1, P-2 and P-3, were prepared from the terpolymerization of butyl p-styrenesulfonate (BSS), methyl methacrylate (MMA) and methacrylic acid (MAA). Thin films composed of the prepared terpolymers, 2,2-bis(4-(2-(vinyloxy)ethoxy)phenyl)propane (BVPP) and an IR dye (in case of laser scanning) were made onto an aluminum substrate. Crosslinking and de-crosslinking reactions would readily take place when the films were treated at 80°C and 220°C for a short period of time, respectively. Along with the chemical structural changes during thermal treatment, great solubility changes could be achieved. It was found that the crosslinked polymer matrix was more resistant to aqueous solution and insoluble in neutral water, whereas the de-crosslinked one such as P-1 matrix could become soluble in neutral water. Based on these properties, a positive-working and neutral water-developable imaging material was proposed and preliminary studies on the imaging property were conducted. [Copyright &y& Elsevier]

Various metal ions, including Mg, Co, Nb, and W, were chfosen for ion implantation to modify TiO 2 nanowire arrays. The introduction of metal ions was confirmed by both simulations and transmission electron microscopy (TEM) morphology characterization. A doped TiO 2 shell on the surface was formed by the ion implantation process. Furthermore, the unbonded metal W was found in the doped TiO 2 nanowires. The XPS results implied a special mechanism of heavy ions chosen for low-energy ion implantation. The presence of non-bonded metal restricted water splitting ability evidently. PEC results provided brief evidence that Nb doped TiO 2 nanowire arrays is a promising choice with a 60% improvement in current density. The charge transfer resistance and the flat band potential are more benefit to water splitting than other doped metal ions. The theoretical calculation also supported efficient band gap narrowing of TiO 2 caused by Nb dopant. [ABSTRACT FROM AUTHOR]

Abstract: The elastic and thermodynamic properties of NiB, Ni2B, Ni3B, orthorhombic Ni4B3(O–Ni4B3), monoclinic Ni4B3(M–Ni4B3), and Ni23B6, are calculated via first-principles method for the Ni–B system. The ground state energies, the full sets of elastic constants and the associated macroscopic elastic parameters of these Ni–B alloys are computed for the first time. Taking contributions from lattice vibrations and thermally excited electrons into account, thermodynamic properties at finite temperatures are then predicted. In addition, we measure the molar heat capacity at constant pressure for NiB and compare the results with the theoretical predictions. Various calculations demonstrate that the first-principles calculation can be used to clarify the diverse experimental data, and provide reliable thermodynamic data. [Copyright &y& Elsevier]

Niobium‑chromium (Nb Cr) carbide coatings were deposited on graphite using the thermo-reactive deposition and diffusion (TRD) technique. The microstructure, hardness, and coefficient of thermal expansion were characterized to search for the optimal treatment parameters for hard and adherent coatings on graphite. The growth rate increased with treatment temperature for fixed treatment duration and remained constant at a constant temperature for about 6 h. The coatings were found to consist of alternating Nb and Cr layers, and this interesting multilayer structure might be explained by the thermodynamics of oxide reduction and carbide formation reactions. Compared to the single-carbides layer, the hardness of the complex coatings increased from about 2500 HV to above 3000 HV, and displayed a smaller gradient of the depth-dependent hardness from the coating to the substrate. The variation of coefficient of thermal expansion of the samples with temperature was similar to that of the graphite substrate at temperatures from 40 to 450 °C. These results showed the effectiveness of the TRD method for synthesizing hard and adherent carbide coatings on graphite, and for other coating/substrate systems with sharply dissimilar mechanical properties. [Display omitted] • Nb Cr complex carbide layers were formed on graphite materials by the TRD technique for the first time. • The maximum coating thicknesses can reach up to 20 μm, positively correlate with the TRD treatment temperature/time. • The elements distributions and unique alternating Nb Cr multilayer structure in the coatings were reported and discussed. • The coatings showed excellent hardness performance (>2500 HV) with good adhesions to the graphite substrates. [ABSTRACT FROM AUTHOR]

The powder immersion reaction assisted coating (PIRAC) method was used to fabricate a coating on the graphite surface. The graphite was immersed into Cr powder and annealed at 1173–1373 K. The iodine powder was admixed with the Cr powder to investigate the contribution of iodine to the growth and mechanical properties of the coating. After 4 h of PIRAC treatment with or without iodine, Cr7C3- and Cr23C6-based coatings were formed, respectively. The iodinated samples had a higher hardness and thickness, and the friction coefficient was slightly higher than that of the iodine-free sample. The mechanisms for the formation of PIRAC-chromium carbide coatings are explained, and the variations in the produced coatings are discussed. [ABSTRACT FROM AUTHOR]

In deposition of nitride films through reactive sputtering, the degree of nitrogen dissociation from N 2 in vacuum chambers is small and difficult to control, while the nitrogen sputtered from a nitride target is in the ionic state, reactive, and tunable through the power of the target. In this study, co-sputtering of TaN target and Ta target is used to prepare tantalum nitride films of Ta 2 N phase with low resistance and low temperature coefficient of resistance (TCR). We investigated effects of the power of the TaN target and annealing temperature on the phase, structure, and electrical properties of the thin films, and obtained an optimal Ta 2 N-phase thin-film with adjustable resistance in the low segment and a TCR of −8 ppm/°C. • The metal Ta atoms from the Ta target easily take over the ion state N component from the TaN target. • Tantalum nitride films with low resistance and low TCR were successfully prepared by co-sputtering Ta and TaN targets. • Vacuum annealing at a medium temperature improves the electrical properties of the film. • The best tantalum nitride film has a square resistance of 2.586 Ω·□−1, a resistivity of 243.084 μΩ·cm, and a TCR of −8 ppm/°C. [ABSTRACT FROM AUTHOR]

Solidly mounted resonators (SMRs) rely on high-quality Bragg reflectors, for which tungsten has been used as the high acoustic impedance layer. It is unclear about the effects of tungsten phases on the acoustic performance of SMRs. In this study, high-quality flat layers of different phase structures of W (α-W and β-W) are obtained by changing the post-growth annealing temperature and magnetron sputtering parameters. Our results show that the α-W has higher Young's modulus and acoustic impedance (205 GPa and 63 kg/m2s) than β-W (170 GPa and 57 kg/m2s). These small differences result in amplified difference in acoustic performance of Bragg reflectors using tungsten (W) as their high-impedance layer. Our tests show that the SMR of α-W Bragg reflector has a higher return loss (18.4 dB) at around 2.75 GHz and higher quality factor (687) than that of β-W Bragg reflector (9.2 dB and 228, respectively). • Different phase structures of W are obtained by changing the annealing temperature and magnetron sputtering parameters. • The acoustic impedance of α-W is 10% higher than that of β-W. • The influence of α- and β-W phases on performance of SMR devices is different. [ABSTRACT FROM AUTHOR]

Activated biomass carbons (ABC) produced from bamboo by carbonization and activation have high specific surface areas and mesoporous structures. The specific surface area, total pore volume, and average pore size of the activated biomass carbon are controlled by adjusting the activation temperature from 700 to 1000 °C. The carbon materials activated at 900 °C have an optimal mesoporous structure with a high specific surface area (2221.1 m 2  g −1 ), the highest capacitance (293 F g −1 at 0.5 A g −1 in 3 M KOH aqueous electrolyte) and excellent rate capability (193.8 F g −1 at 20 A g −1 ). Symmetric supercapacitors made of the optimal electrodes exhibit a high energy density of 10.9 Wh kg −1 (18.2 Wh L −1 ) at a power density of 63 W kg −1 (105 W L −1 ) and outstanding capacitance retention of 91.8% over 10,000 cycles. The high electrochemical performance of the mesoporous ABCs show that they are highly promising for energy-storage applications with further optimization. [ABSTRACT FROM AUTHOR]

Devices based on AlN generally require adherent and strong interfaces between AlN and other materials, whereas most metals are known to be nonwetting to AlN and form relatively weak interfaces with AlN. In this study, we selected four representative metals (Al, Cu, Ti, and Zr) to study the adhesion strength of the AlN/metal interfaces. Mathematical models were constructed between the adhesion strength and enthalpy of formation of Al–metal solid solutions, the surface energies of the metals, and the lattice mismatch between the metals and AlN, based on thermodynamic parameters calculated using density functional theory. It appears that the adhesion strength is mainly determined by the lattice mismatch, and is in no linear correlation with either the Al–metal solution's formation enthalpies or the metals’ surface energies. We also investigated the nucleation thermodynamics of the four metals on AlN substrates. It was found that Ti forms the strongest interface with AlN, and has the largest driving force for nucleation on AlN substrates among the four metals. [ABSTRACT FROM AUTHOR]

Ordered mesoporous carbon CMK-3 was successfully prepared by a hard template nanocasting method followed by carbonization at temperatures from 700 to 900 °C. The values of specific surface area, pore diameter and pore volume were found to increase with the rise of carbonization temperatures. After chemical activation by 6 M HNO 3 , the specific surface areas decreased significantly, but the specific capacitances increased remarkably in both alkaline (3 M KOH) and neutral (0.5 M Na 2 SO 4 ) electrolytes. Analysis of the surface structure and composition showed that the chemical activation introduced oxygen-containing functional groups on carbon surface, which are responsible for the enhancement of supercapacitive performances revealed by electrochemical tests. The best achieved specific capacitance is 182.1 F/g in 0.5 M Na 2 SO 4 , and 223.5 F/g in 3 M KOH, both at the current density of 0.5 A/g. The specific capacitance retentions after 500 cycles are 95.6% and 86.3% in 0.5 M Na 2 SO 4 and 3 M KOH, respectively. The higher specific capacitance in KOH electrolyte is due to the lower faradic charge transfer resistance and better electrochemical surface area utilization than in Na 2 SO 4 electrolyte. [ABSTRACT FROM AUTHOR]

Abstract: This paper develops a relative position and attitude estimation approach for satellite formation. A coupled relative translational dynamics is derived to represent orbital motion of arbitrary feature points on deputy, and the relative attitude motion is formulated by a rotational dynamics for no-gyro satellite. A position sensitive diode (PSD) sensor is used to provide multiple line-of-sight (LOS) vectors from a feature point to beacons fixed on the chief. The LOS measurements are coupled with dynamical models in an extended Kalman filter (EKF) to estimate relative attitude of the deputy and relative position of the feature point. Four different scenarios are simulated to validate that the estimation accuracy is affected by the beacons configuration and measurement distance. Through comparisons, the proposed approach is approved to provide high accurate relative attitude and position estimation for the no-gyro satellite. [Copyright &y& Elsevier]

AlCu x NiTiZr 0.75 high entropy alloy (HEA) films were deposited by magnetron sputtering with an alloy target in combination with a pure Cu metal target. The purpose of this study was to reduce electrical resistivity of the HEA films while maintaining mechanical properties and corrosion resistance by adjusting Cu content of the HEA. We found that the AlCu x NiTiZr 0.75 HEA films were amorphous and displayed a homogeneous or columnar microstructure along the cross sections. The increase of Cu content changed the electronic structure of the HEA films, so that the resistivity decreased sharply to 66 μΩ·cm at x = 1.4. The hardness-to-elastic modulus ration H/E, an indicator of a material's ductility, attained the maximum value at x = 1.4. Although the corrosion current densities increased with x , they were all below 10−6 A/cm2 in 3.5 wt% NaCl solution, indicating good corrosion resistance. These findings assumably help expand industrial application of HEA films, particularly when conductivity is required for the functionality of the films. • Amorphous AlCuxNiTiZr 0.75 high entropy alloy films were deposited by co-sputtering. • AlCuxNiTiZr 0.75 films maintained high hardness and good corrosion resistance. • The electronic structure of AlCuxNiTiZr 0.75 films were changed, and the lowest resistivity was 66 μΩ·cm. [ABSTRACT FROM AUTHOR]

• Surface energies of YF 3 are in the order of { 020 } < { 111 } < { 10 1 ¯ } < { 1 ¯ 02 }. • The Wulff shape of YF 3 is truncated octahedron, and may expose { 1 ¯ 02 } facets under extremely fluorine-lean conditions. • Inverse Wulff construction method is used to calculate the required surface energies that correspond to the experimentally observed shapes. Shape and size of YF 3 particles are determinant in hydrothermal synthesis experiments, whereas the surfaces' structural and thermodynamic parameters are largely unknown but are indispensable for further optimizations to the YF 3 micro- and nanocrystals. In this work we focus on {020}, {111}, { 10 1 ¯ } and { 1 ¯ 02 } facets that are frequently observed. For each orientation, structures and surface energies are obtained using density functional theory calculations. The surface energies are found to be in the order of { 020 } < { 111 } < { 10 1 ¯ } < { 1 ¯ 02 }. The Wulff shape is truncated octahedron, and may expose { 1 ¯ 02 } facets under fluorine-lean conditions. For other experimentally observed shapes (octahedron and diamond-like polyhedron), we present necessary modifications to the surface energies through the inverse Wulff construction method. The results are expected to be helpful in choosing surface-specific surfactants in synthesizing YF 3 crystals with targeted morphologies. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Multiple terminations of surfaces (10 1 ¯ 0) , (10 1 ¯ 1) , (11 2 ¯ 0) , and (0001) of Y(OH) 3 are established. • Effects of temperature and partial pressure of water and oxygen are included through first-principles thermodynamics. • The equilibrium morphology is of elongated hexagonal bipyramid enclosed by stoichiometric surfaces. Yttrium hydroxide Y(OH) 3 is an important precursor for yttrium oxides, and its morphologies are inherited by the yttrium oxides, thus affecting the products' properties and performance. Hydrothermally synthesized Y(OH) 3 particles are typically elongated hexagonal bipyramid, but thermodynamic parameters are inadequate for quantitative modeling of the morphology. We calculate surface energies and surface stresses of low-index orientations using density functional theory, and present a thermodynamic morphology model based on these parameters. We find that the thermodynamically stable surface terminations are always stoichiometric, and the surface energies are in the order of γ (10 1 ¯ 0) < γ (10 1 ¯ 1) < γ (11 2 ¯ 0) < γ (0001). The equilibrium morphology is of hexagonal prism capped by hexagonal pyramid enclosed by (10 1 ¯ 1) and (10 1 ¯ 0) surfaces. Because these terminations are stoichiometric, varying temperature or pressure is ineffective for modifying Y(OH) 3 particles' morphology, whereas surfactants should be used for this purpose in hydrothermal synthesis. Image, graphical abstract [ABSTRACT FROM AUTHOR]