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A series of 16 mol% CeO 2 -2 mol% Re 2 O 3 co-stabilised zirconia (ZrO 2) (16Ce4ReSZ, Re Eu, Gd, Dy, Y, Er, Yb) ceramic materials were synthesised using a chemical coprecipitation– high-temperature roasting method. Their phase structure, high-temperature phase stability, mechanical properties, thermal conductivity and coefficient of thermal expansion (CTE) were investigated. The results show that the ZrO 2 tetragonal phase co-stabilised by CeO 2 and Re3+ with a smaller radius has better stability. The 16Ce4ReSZ (Re Dy, Y, Er, Yb) materials have high fracture toughnesses, low thermal conductivities, and high CTE values. As the radius of the Re3+ ions decreases, the lattice energy increased, while the lattice distortion decreases, the CTE decreases slightly and the thermal conductivity of the material increases slightly. Owing to the high phase stability of 16Ce4YbSZ, its mechanical properties are best after 100 h of sintering at 1400 °C. [ABSTRACT FROM AUTHOR]

CeO 2 and Sc 2 O 3 co-stabilized ZrO 2 ceramics have attracted much attention as potential thermal barrier coatings (TBCs) materials for applications above 1300 °C. In this study, a series of Sc 0.04 Ce x Zr 0.96-x O 1.98 (SCZ, x = 0.08, 0.10, 0.12, 0.16) ceramic materials were synthesized with the solid-state method and their phase stability, microstructures and thermo-physical properties were systemically investigated by x-ray diffraction (XRD), Raman spectra, field emission scanning electron microscopy (SEM), thermal dilatometer, laser flash apparatus (LFA), and Vickers hardness tester. The results showed that Sc 0.04 Ce 0.12 Zr 0.84 O 1.98 (4S12CZ) and Sc 0.04 Ce 0.16 Zr 0.80 O 1.98 (4S16CZ) ceramic materials still maintained stable tetragonal phase structure after 100 h high temperature treatment at 1500 °C. SCZ had a high thermal expansion coefficient (TEC), low thermal conductivity, and high fracture toughness. The TEC of the ceramics increased with CeO 2 addition because lattice energy reduced with increasing substitution of Zr4+ by bigger Ce4+ while thermal conductivity decreased due to the increase of lattice distortion. Compared with 4S12CZ, 4S16CZ exhibited a higher fracture toughness of 6.48 ± 0.04 MPa m1/2 and showed the better anti-sintering property. Besides, the thermal conductivity, TEC and thermal cycling lifetime of 4S16CZ were optimal. The comprehensive performance of 4S16CZ suggested it could be explored as a promising TBC material for high-temperature application. [ABSTRACT FROM AUTHOR]

Although hydrogen automobile has attracted increasing attention in recent years, previous studies did not extensively investigate customers' purchase intention for hydrogen automobile, as well as the factors that might affect their purchase intention. The present study therefore investigated whether customers' environmental concern and perceived social value of green buying would affect their purchase intention for hydrogen automobile. Customers' green buying behavior was included as a mediator, and their monthly income and gender were included as moderators. Data from 300 adults in China were collected. Results from structural equation modeling showed that customers' green buying behavior fully mediated the positive association between perceived social value and purchase intention for hydrogen automobile. Further multi-group analysis found that monthly income and gender had moderating effects on the associations between some of the study variables. Based on these findings, possible explanation and practical implications were discussed. • Citizens' purchase intention for hydrogen automobile was impacted by social value. • This association was fully mediated by customers' green buying behavior. • High-income customers' green buying behavior impacted purchase intention stronger. • The indirect effect of Environmental Concern was only significant for males. [ABSTRACT FROM AUTHOR]

The affective quality of teacher-student relationships (TSRs) has mostly been studied in Western contexts and little is known how findings generalize to Eastern contexts. Therefore, the present study examined measurement invariance, mean differences, and agreement in teachers' and students' perceptions of relationship quality between the Netherlands and China. The sample consisted of 789 primary school students (51% girls) and 35 teachers (80% female) from the Netherlands, and 587 primary school students (53% girls) and 14 teachers (93% female) from Zhejiang, China. Both teachers and students reported about the quality of their mutual relationships. Structural equation modeling showed that teachers' perceptions of closeness, conflict and dependency, as well as students' perceptions of closeness and conflict in the relationship, reached partially strong invariance. Chinese students perceived more closeness and less conflict with teachers than Dutch students. Chinese teachers also reported less conflict but comparable levels of closeness and dependency as Dutch teachers. Chinese teacher-student dyads had higher agreement on closeness but lower agreement on conflict than Dutch teacher-student dyads. Implications and suggestions for future research are discussed. [ABSTRACT FROM AUTHOR]

Fluorination reduces dielectric constant and dielectric loss of epoxy resins, expanding their applications in high-speed communication. The methyl group (-CH 3) is a non-polar and space-occupying group, and it can reduce dielectric constant (D k) in some situations. However, it is not well understood how the methyl groups affect dielectric properties, as well as thermal and mechanical properties of fluorinated epoxy resin. To address this question, we specifically select benzene and m-xylene as the reaction monomer for comparison. We synthesize two fluorinated epoxides, diglycidyl ether of 1,3-bis(1,1,1,3,3,3-hexafluoroisopropyl)-benzene (DGE-bHFIP-B) and diglycidyl ether of 4,6-bis(1,1,1,3,3,3-hexafluoroisopropyl)-m-xylene (DGE-bHFIP-MX). We then thermally cure these two epoxides catalyzed with boron trifluoride ethylamine (BF 3 ·MEA) to obtain EP-bHFIP-B and EP-bHFIP-MX. EP-bHFIP-MX with –CH 3 has D k of 2.49–2.51, slightly lower than EP-bHFIP-B with D k of 2.51–2.54 at a high frequency range of 8.2–12.4 GHz. Their D k is much lower than a commercial bisphenol A type epoxy resin (EP-51) with D k of 2.80–2.83. Additionally, EP-bHFIP-MX shrinks less than EP-bHFIP-B after curing, and exhibits higher glass transition temperature with T g − D M A of 181 °C, higher tensile strength of 39.76 ± 5.51 MPa, compared to 129 °C and 34.73 ± 5.10 MPa for EP-bHFIP-B. EP-bHFIP-B and EP-bHFIP-MX both have very low water absorption of 0.134% w/w and 0.147% w/w after being immersed in water for 24 h at 25 °C. Therefore, incorporating –CH 3 groups into phenylene rings of fluorinated epoxies, we can enhance thermal resistance, increase mechanical strength, and reduce shrinkage without compromising dielectric performance. [Display omitted] • Two novel fluorinated epoxides with low dielectric constant are synthesized. • Methyl-substitution slightly decreases D k in fluroinated expoxies. • Methyl-substitution improves thermal, mechanical properties and reduces curing shrinkage. [ABSTRACT FROM AUTHOR]

• Ultracentrifugation (UC) is recommended to separate and enrich field nanoplastics. • Fragmented nanoplastic spikes are prepared using ultrasonic probe sonicator. • UC is validated with environmentally relevant concentration of nanoplastic spikes. • UC can separate and enrich nanoplastics in river water with a high recovery rate. Nanoplastics are an emerging contaminant in aquatic environments. However, analytical methods for the separation, concentration, and identification of nanoplastics, which are essential to assess nanoplastic presence in the environment, are lacking. Here, we developed a new and easy-to-use method to separate and enrich nanoplastics in field water samples with ultracentrifugation. River water was spiked with polystyrene fragments (< 1000 nm) at an environmentally relevant concentration (108–109 particles/L). The polystyrene fragments were successfully separated and enriched by a factor of nearly 50 times with a high recovery rate (87.1%) after undergoing our process. Particles were then characterized using UV-vis spectroscopy, scanning electron microscopy (SEM), and enhanced darkfield microscopy with a hyperspectral imaging (HSI) spectrometer. These techniques are non-destructive and allow the assessment of plastic concentration, morphology, and polymer type. Our method can potentially be applied to other water samples to supply clean, enriched nanoplastic samples that can facilitate their identification in environmental samples. [Display omitted] [ABSTRACT FROM AUTHOR]

Students' shyness was found to harm teacher-student relationship quality in Western contexts, whereas less is known about how shyness is associated with teacher-student relationships in Eastern contexts. The present study therefore examined cultural differences in the association between students' shyness and affective teacher–student relationships between the Netherlands and China. The Dutch sample included 789 third to sixth grade students and 35 teachers, and the Chinese sample consisted of 587 third to sixth graders and 14 teachers. Students reported their own levels of shyness and both teachers and students reported the quality of their mutual relationships. Multilevel regression analysis showed that shyness was associated with less student-reported closeness and more conflict in both countries; these associations were stronger in the Chinese than in the Dutch sample. In both countries, shyness was associated with less teacher-reported closeness but not with more conflict; no cultural difference was found in these associations. Possible explanations and implications are discussed. • Relationships between shy children and their teachers may vary across cultures. • Shyness was linked to less student-reported closeness and more conflict. • These associations were stronger for Chinese than for Dutch students. • Shyness was only associated with less teacher-reported closeness in both samples. • Shyness may be as problematic in Eastern as in Western contexts. [ABSTRACT FROM AUTHOR]

Filters of various structures (filter by pore depth or pore width) and pore sizes are used to extract microplastics (<5 mm) in researches. In present study, we demonstrate that filters with different structures and pore sizes can lead to different outcomes in microplastic filtering. Our results showed that when filtering large-sized microplastics, nylon filter (double-layer-hole type) retained nearly 100% of fibers, while polycarbonate filter (single-layer-hole type) only retained 61.7%. Polycarbonate filter retained the most fragments (80.8%), while cotton fiber filter (multilayer-hole type) retained the least (54.4%). Pellets were retained on different layers of nylon and cotton fiber filters, and could not be quantified accurately. Additionally, the sizes of some fibers and fragments captured were not within the expected ranges by lattice-knitting filters. Large fiber (3568.0 μm) was not filtered out after 1000 μm pore-size filtration. Small fragment (37.2 μm) was found on 50 μm pore-size filters. To validate laboratory results, filed waters containing microplastics (∼90% in form of fibers) were filtered through different pore-size filters. As expected, the relationship between abundance and pore size followed a same trend as that in laboratory fiber samples. Thereby, our results indicated that filter structure and pore size could affect the abundances of microplastics with different shapes. To obtain more accurate abundance of microplastics in a wide size range, and to consider filtration duration, size limitation of observation, and spatial resolution of identification instrument, we recommend that water samples should be filtered using 20 μm pore-size filters with a double-layer-hole type of structure. Image 1 • Filter structure can affect abundance of retained microplastics of different shapes. • Small pore size filter leads to high abundance and wide size range of microplastic. • Filtering with 20 μm filter are efficient for field investigation of microplastic. [ABSTRACT FROM AUTHOR]

The present study investigated the effect of solid digestates from first (FD) and second (SD) runs of anaerobic digestion on rice straw (S) degradation and biogas production. The results indicated that co-digestion of digestate (D) increases the relative lignin content in favor of cellulose and hemicellulose. In addition, digestate enhanced the biomethane content of biogas under both mesophilic and thermophilic conditions. Therefore, different ratios of D:S were further studied. The lowest fiber contents after mesophilic co-digestion (14.0% cellulose, 11.1% hemicellulose and 7.4% lignin) were recorded with FD:S 2:1, which showed insignificant differences with those of FD:S 1:1. Thermophilic anaerobic digestion resulted in slight changes in fiber content among all studied digestate ratios, which confirms that addition of digestate during thermophilic anaerobic digestion speeds up the rate of the process rather than fiber degradation. All applied digestate ratios resulted in shift in the time of maximum biogas production. Therefore, the maximum biogas productivities of 8.5 and 12.4 L kg−1 VS d−1 under mesophilic and thermophilic anaerobic co-digestion were recorded using 1:1 FD:S and 1:1 SD:S, which represented 46.6% and 25.3%, respectively, over the corresponding control. The present study suggests a novel approach of solid digestate recycling that enhances pH stabilization and biogas production. Image 1 • Effect of first digestate (FD) and second digestate (SD) was evaluated. • Digestate enhanced the relative lignin content in favor of holocellulose. • Digestate resulted in lower biogas yield, but shorter peak time and higher biomethane content. • Digestate improved the pH value of digester due to enhancement of VFAs consumption. • SD1:1 showed the maximum methane productivity of 7.5 L kg−1 VS d−1 under thermophilic AD. [ABSTRACT FROM AUTHOR]

• Sensitivity of {1 1 1} faced CdO octahedrons is signally enhanced by hydrogenation. • Density of 3-coordinated Cd atoms at (1 1 1) surface is increased by hydrogenation. • The 3-coordinated Cd atoms are regarded to function as the sensing reactive centers. • They can absorb oxygen, generate free electrons and catalyze the sensing reaction. • Properties of other sensing materials and catalysts may be enhanced by hydrogenation. As a surface optimization strategy, hydrogenation has been successfully used to enhancing the responses of CdO octahedrons sensors to acetone, ethanol and triethylamine by increasing the numbers of 3-coordinate Cd (Cd 3c) atoms on the CdO (111) surface. The Cd 3c atom with three dangling bonds at Cd-CdO (111) surface is considered to be a reactive center for gas sensing, which has three functions: adsorbing oxygen from air, generating free electrons, and catalyzing the redox reaction of the target gas with adsorbed oxygen. The sensing mechanism of surface Cd 3c atom acting as a reactive center can not only deepen understanding the mechanisms of gas sensing and heterogeneous catalytic reactions, but also provide a new insight for developing highly performance sensing and catalytic materials. In addition, hydrogenation may be a general effective strategy for improving sensing and catalytic performances of semiconductor materials. [ABSTRACT FROM AUTHOR]

In this study, the destabilization resistance of Sc 2 O 3 and CeO 2 co-stabilized ZrO 2 (SCZ) ceramics was tested in Na 2 SO 4 + V 2 O 5 molten salts at 750°C–1100 °C. The phase structure and microstructure evolution of the samples during the hot corrosion testing were analyzed with X-ray diffraction (XRD), Raman spectra, scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS), and X-ray photoelectron spectroscopy (XPS). Results showed that the destabilization of SCZ ceramics at 750 °C was the result of the chemical reaction with V 2 O 5 to produce m-ZrO 2 and CeVO 4 , and little ScVO 4 was detected in the Sc 2 O 3 -rich SCZ ceramics. The primary corrosion products at 900 °C and 1100 °C were CeO 2 and m-ZrO 2 due to the mineralization effect. The Sc 2 O 3 -rich SCZ ceramics exhibited excellent degradation resistance and phase stability owing to the enhanced bond strength and the decreased size misfit between Zr4+ and Sc3+. The destabilization mechanism of SCZ ceramic under hot corrosion was also discussed. [ABSTRACT FROM AUTHOR]

High-temperature degradation of the plasma sprayed 16 mol% TaO 2.5 + 16 mol% YO 1.5 co-stabilized ZrO 2 (YTZ) and YSZ (7.6 wt% Y 2 O 3 -stabilized ZrO 2) coatings under calcium-magnesium-aluminon-silicate (CMAS) attack at 1200 °C and 1250 °C were comparatively investigated. Results indicated that the coatings were insensitive to the infiltration of CMAS after 10 h corrosion at 1200 °C. At 1250 °C, the entire YSZ cross-section completely failed and also underwent serious chemical corrosion after 3 h hot corrosion. Even after 10 h corrosion, the penetration depth of CMAS into the YTZ was only about 80 µm. For YTZ coating, the YTaO 4 stabilizer could not easily dissolve in CMAS and precipitated out of the YTZ crystal lattice owing to the strong chemical interaction between Ta5+ and Y3+. The wettability of CMAS on YTZ coating was worse than that on YSZ coating. Compared with YSZ coating, the YTZ coating showed better resistance to CMAS corrosion. [ABSTRACT FROM AUTHOR]

• Bioethanol was produced from rice straw (RS) by cellulosic alcoholic fermentation. • Vinasse (VE) was used in anaerobic co-digestion with RS and swine manure (SM). • RS-VE co-digestion enhanced biogas yield and biomethane content. • Highest biomethane productivity (29.2 L kg−1 VS d−1) was recorded with SM-VE. • SM-VE co-digestion showed the highest energy output rate of 2.04 GJ ton−1 dw d−1. Cellulosic alcoholic fermentation generates large amounts of vinasse, which was utilized in the present work to enhance the anaerobic digestion of rice straw and swine manure at different total solid (TS) contents. Straw fermentation resulted in bioethanol and vinasse yields of 95.2 g and 857.7 mL, respectively, per kg dry straw. Vinasse-straw co-digestion showed the highest cumulative biogas yield of 633.4 L kg−1 VS at 3% TS. Therefore, biogas productivity from co-digestion represented 92.1% higher than that of straw mono-digestion. Vinasse-manure co-digestion showed the highest cumulative biogas yield of 676.7 L kg−1 VS at 3% TS at a shorter technical digestion time, which resulted in 53.9% higher biomethane productivity than the corresponding vinasse-straw. Consequently, vinasse co-digestion at all studied TS ratios enhanced the total gross energy output rate (GEOR total) over mono-digestion. Amongst, vinasse-manure co-digestion at 3% TS showed 7.9% higher GEOR total than the highest recorded value from vinasse-straw co-digestion. [ABSTRACT FROM AUTHOR]