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The photocatalyst film, composed of tetragonal BiOI nanosheets and cubic phase CuI nanoparticles, was synthesized on the FTO substrate by a simple electro-deposition method. The orderly crisscrossed nanosheet structure caused exterior hydrophobic property, resisting the excess H 2 O molecules and further inhibiting the competitive H 2 O reduction process. The novel BiOI/CuI catalyst exhibited excellent photocatalytic ability of CO 2 reduction into CO with 100 % selectivity in H 2 O vapor. Typically, the optimal 150BiOI/CuI photocatalyst exhibited CO yield of 7237.65 μmol/cm2 after 11 h of simulated sunlight illumination, achieving quantum efficiency of 2.5 % at 380 nm. The excellent performance of the BiOI/CuI composite film in photocatalytic CO 2 reduction can be attributed to the construction of hydrophobic surface and S-scheme heterojunction with I 3 −/I− redox mediator, as confirmed by the in-situ XPS, hole injection test and cyclic voltammetry results. This study lays the groundwork for employing highly efficient iodide-based photocatalysts in gas-liquid-solid triphase catalytic systems. Variable valence I 3 −/I− ionic bridge CuI nanoparticle/BiOI nanosheet S-scheme photocatalyst with hydrophobic surface exhibited the efficient conversion from CO 2 to CO with 2.5 % apparent quantum efficiency at 380 nm light. [Display omitted] [ABSTRACT FROM AUTHOR]

Rational design and construction of Step-scheme (S-scheme) photocatalyst have attracted considerable attention in the photocatalytic field. In this study, a series of Step-scheme (S-scheme) CuBi 2 O 4 /Na doped P25 photocatalysts (CBO/Na–P25) were synthesized through a facile hydrothermal method. CBO/Na–P25 photocatalyst without co-catalyst exhibited good photocatalytic performance for hydrogen evolution, and the H 2 yield rate of the 7.5%CBO/Na–P25 sample achieved 2695.73 μmol/g cat /h after 4 h of illumination, which was more than 37.8, 13.7 and above 100 times those of pure P25, Na–P25 and CuBi 2 O 4. The calculated apparent band gap of P25 decreased by Na doping and the construction of CuBi 2 O 4 /Na–P25 heterojunction contributed to efficient interfacial charge separation. Meanwhile, the S-scheme carrier transfer mechanism for the CuBi 2 O 4 /Na–P25 heterojunction photocatalyst was verified by the experimental results under different light wavelengths. This work demonstrated that the P25 based S-scheme heterojunction is a promising photocatalyst for hydrogen evolution. [Display omitted] • CuBi 2 O 4 /Na doped P25 was synthesized through a facile hydrothermal method. • CuBi 2 O 4 /Na–P25 without co-catalyst realized the photocatalysis for H 2 evolution. • S-scheme carrier transfer mechanism of CuBi 2 O 4 /Na–P25 heterojunction was verified. • Na doping widen the photoinduced range of P25 and enhanced electron transfer ability. [ABSTRACT FROM AUTHOR]

Photo-assisted gas sensors for n-butyl alcohol detection have attracted considerable attention due to their great potential in safety production and human health. However, the sensitivity, selectivity and stability should be further improved for practical application. Herein, Bi 2 WO 6 nanosheet supported on CuBi 2 O 4 nanorod sensor was realized by the two-step hydrothermal method, and it exhibited excellent sensitivity and stability for n-butyl alcohol detection under blue LED light illumination at the operating work temperature of 110 °C with gas concentration from 0.5 to 800 ppm. Meanwhile, the gas concentration of n-butyl alcohol obtained from the sensor was comparable to that of GC analysis. Furthermore, the sensor showed lower responses to other 25 kinds of common organic gases including alcohols, aldehydes, benzenes and ketones compared with that of n-butyl alcohol. More attractively, the Bi 2 WO 6 /CuBi 2 O 4 sensor maintained its stable photo-assisted sensing activity over 3 months. The excellent gas-sensing property was caused by light illumination and formation of Bi 2 WO 6 /CuBi 2 O 4 heterojunction, leading to abundant active electrons and superoxide radicals. The S-scheme mode of charge transfer at the Bi 2 WO 6 /CuBi 2 O 4 heterojunction was revealed by the in-situ XPS and in-situ ESR analyses. The results gained herein may be useful for rational design of S-scheme heterojunction in photo-assisted gas sensor for n-butyl alcohol analysis. [Display omitted] • Bi 2 WO 6 nanosheet/CuBi 2 O 4 nanorod heterojunction was synthesized for the first time. • The photoassisted n-butyl alcohol sensor exhibited good selectivity and stability. • The widened linear correlation for n-butyl alcohol analysis was built. • The S-scheme heterojunction between Bi 2 WO 6 and CuBi 2 O 4 was proven. [ABSTRACT FROM AUTHOR]

Highlights • Ti is a potential low activation interlayer material to bond W/Steel for first wall application. • Microstructure and mechanical properties of W/Ti/Steel joints can be affected at lower deuterium concentration. • Ti interlayers crush into powder and W/Ti/Steel joints are failed at higher deuterium concentration. • Concentration of H isotope in W/Ti/Steel joints shall be strictly controlled for safety operation of fusion reactor. Abstract The first wall (FW) of a water cooled ceramic breeder (WCCB) blanket uses ferritic/martensitic steel (FMS) as structural material and tungsten (W) as armor material. The FW is exposed to fusion reaction fuels: deuterium (D) or tritium (T) plasma; and HT, T 2 , or HTO produced in breeding reactions. Titanium (Ti) is required as an interlayer in a W/FMS welding joint formed by hot isostatic pressing (HIP). However, Ti is sensitive to hydrogen (H) embrittlement which can result from the concentration and diffusion of H isotopes at welding interfaces. Qualitative analysis of the effect of D concentration on the W/Ti/FMS bonding quality was performed. The experiments demonstrated that D can affect the microstructure and mechanical properties of the W/Ti/FMS joints at lower D concentrations. Excessive TiD 2 will turn the Ti interlayer into powder, and finally lead to joint failure at higher D concentrations. The H isotope concentration in the joints shall be strictly controlled to ensure steady operation of the fusion reactor. [ABSTRACT FROM AUTHOR]

Enhancing photocatalytic efficiency of mixed-pollutant degradation is a critical issue for the application in wastewater purification, especially under natural-sunlight illumination. CuBi 2 O 4 rods decorated with Fe 2 O 3 nanoparticles were synthesized by the hydrothermal method. The Fe 2 O 3 /CuBi 2 O 4 composites exhibited significantly enhanced photocatalytic activity for Fenton oxidation of Rhodamine B (RhB) and 4-nitrophenol (4-NP) in the near-neutral catalytic system, and the degradation efficiency of the above two pollutants reached above 90% after 50 min of visible-light irradiation. Meanwhile, the good catalytic performance and stability were maintained in the seventh cycling test. Notably, the efficient synchronous degradation of the above mixed pollutants was accomplished under natural-sunlight over the optimal 7%Fe 2 O 3 /CuBi 2 O 4 catalyst. The staggered band structure in the heterojunction was determined by DRS and UPS results, and the S-scheme electron transfer mode was verified by the in situ-XPS measurement under dark and light conditions. The study is expected to be beneficial to explore step-scheme (S-scheme) semiconductor photocatalysts for natural-sunlight-driven Fenton oxidation of mixed pollutants. [Display omitted] • Fe 2 O 3 nanoparticles decorated CuBi 2 O 4 rods was synthesized. • The photocatalysis for mixed degradation was accomplished under natural light. • The 4-NP and RhB degradation performance was promoted by the heterojunction. • S-scheme charge transfer was proven by the in situ-XPS measurement. [ABSTRACT FROM AUTHOR]

Conjugated polymers have emerged as a promising class of organic photocatalysts for photocatalytic hydrogen evolution from water splitting due to their adjustable chemical structures and electronic properties. However, developing highly efficient organic polymer photocatalysts with high photocatalytic activity for hydrogen evolution remains a significant challenge. Herein, we present an efficient approach to enhance the photocatalytic performance of linear conjugated polymers by modifying the surface chemistry via introducing a hydrophilic adenine group into the side chain. The adenine unit with five nitrogen atoms could enhance the interaction between the surface of polymer photocatalyst and water molecules through the formation of hydrogen bonding, which improves the hydrophilicity and dispersity of the resulting polymer photocatalyst in the photocatalytic reaction solution. In addition, the strong electron-donating ability of adenine group with plentiful nitrogen atoms could promote the separation of light-induced electrons and holes. As a result, the adenine-functionalized conjugated polymer PF6A-DBTO2 shows a high photocatalytic activity with a hydrogen evolution rate (HER) of 25.21 mmol g−1 h−1 under UV-Vis light irradiation, which is much higher than that of its counterpart polymer PF6-DBTO2 without the adenine group (6.53 mmol g−1 h−1). More importantly, PF6A-DBTO2 without addition of a Pt co-catalyst also exhibits an impressive HER of 21.93 mmol g−1 h−1 under visible light (λ > 420 nm). This work highlights that it is an efficient strategy to improve the photocatalytic activity of conjugated polymer photocatalysts by the modification of surface chemistry. An adenine-functionalized conjugated polymer PF6A-DBTO2 was constructed and developed as an efficient photocatalyst for hydrogen evolution from water. A hydrogen evolution rate (HER) of 25.21 mmol g−1 h−1 was obtained for PF6A-DBTO2 without addition of a Pt co-catalyst, which is much higher than that of its counterpart polymer PF6-DBTO2 with alkyl side chains. [Display omitted] • An adenine-functionalized conjugated polymer was developed for highly efficient photocatalytic hydrogen evolution. • The enhanced contact between adenine groups and water enables more efficient charge transfer and separation. • The adenine-containing polymer photocatalyst exhibited a much higher HER than the counterpart polymer with alkyl chains. [ABSTRACT FROM AUTHOR]

Monitoring threatened species at the individual level is fundamental and crucial in ecology and conservation, especially for critically endangered species. Hainan gibbon (Nomasucs hainanus) is the world's rarest primate species with <40 individuals, urgently needs a labor-efficient and continuous individual-level monitoring system to inform science-based conservation actions. Male dispersal, replacement, and formation of new groups with females are crucial for the population dynamics of gibbons. Their loud and elaborate morning songs provide the potential to automate the monitoring of their dynamics. Based on acoustic recordings from focal recording and 13 autonomous recording units within gibbons' home ranges, we developed an automated system, which successively (a) detected song bouts (duration ≈ 10 min, with ≈ 50 phrases) with temporal parameters using an energy detector with a hidden Markov model (F1 score >75 %), (b) detected and classified phrases (duration ≈ 5 s) within song bouts using a random forest model (F1 score ≈ 80–90 %), and (c) classified known individuals by a linear support vector machine (accuracy >93 %), and recognized unknown individuals by Gaussian mixture models (accuracy >90 %). The system successfully monitored a male immigration and kept tracking a dispersing male for nearly a year since it left the natal group to establish its own group with two females. Our system is effective even in the face of an ever-changing population and can be applied to passive acoustic data. It will contribute to the realization of long-term, large-scale, and continuous monitoring of individual dynamics for vocal animals. • We identified and tracked the dispersal of male Hainan gibbons with an automated system. • The system needs little training data and is robust against data variations. • The system helps to monitor individual dynamics from passive acoustics continuously. [ABSTRACT FROM AUTHOR]

Herein, cobalt embedded in nitrogen-doped porous carbon (Co@NC) was developed as a robust heterogeneous catalyst for the dehydrogenative coupling of primary alcohols and hydroxides. With Co@NC as the first earth-abundant metal/carbon composite material for this transformation, numerous aromatic and aliphatic carboxylic acids were efficiently afforded. Notably, the newly prepared Co@NC was fabricated in a facile and straightforward manner and reused up to 15 recycle rounds without activity decay. It is also worth emphasizing that the catalyst recycling was realized via magnetic separation with no special treatment or activation. Additionally, further experiments elucidated the pivotal role of the cobalt and nitrogen elements dispersed in the carbon matrix as well as the hierarchical porosity (micro-/meso-pores) in the catalytic activity and recyclability. Considering the active sites of Co@NC, we envisioned that the Co–N species was the most active site, while other active sites such as Co–O, Co0 species and free N-doped carbon were also present, but demonstrating lower activity or stability in comparison with the Co–N species. Additional mechanistic investigations were carried out to gain more insights into the possible reaction pathways. We found that the aldehyde was identified as a crucial intermediate, and two possible pathways were proposed for this catalytic process. Image 1 • Co embedded in nitrogen-doped porous carbon as a robust heterogeneous catalyst. • The 1st earth-abundant metal/carbon material for the alcohol dehydrogenation to acids. • Recyclable for 15 times by magnetic separation without special treatment/activation. • Unique porous structure and well-dispersion of Co and N within the carbon matrix. • Investigation of active catalytic sites and reaction pathways. [ABSTRACT FROM AUTHOR]

Surgery is the definitive treatment option for symptomatic Chiari malformation I (CMI), but there is no clear consensus as to the preferred surgical method. This study aimed to quantitatively assess and compare the effect and safety of dura splitting decompression (DSD) and posterior fossa decompression with duraplasty (PFDD) in treating patients with CMI. A literature search of EMBASE, MEDLINE, PubMed, Cochrane Library, and Web of Science databases was conducted. References from January 1990 to September 2020 were retrieved. We only included papers containing original data, comparing the use of DSD and PFDD in CMI patients. Overall, 11 relevant studies were identified, wherein 443 patients treated for CMI by DSD were compared with 261 patients treated by PFDD. No difference was observed between PFDD and PFD in terms of clinical improvement (P = 0.69), syringomyelia improvement (P = 0.90), or reoperation (P = 0.22). DSD was associated with shorter operation durations (P = 0.0007), shorter length of stay (P = 0.0007), and shorter overall postoperative complications (P < 0.0001) (especially cerebrospinal fluid [CSF] leak P = 0.005], meningitis P = 0.002], and pseudomeningocele P = 0.002]), as compared with PFDD. This study confirmed that dura splitting decompression has clinical and syringomyelia improvement outcomes comparable to posterior fossa decompression with duraplasty. Compared with PFDD, DSD not only significantly shortened the operation time and length of stay, but also significantly reduced the overall complication rate, especially those related to incidence of CSF-related complications. More evidence from advanced multicenter studies are needed to require to validate the findings. [ABSTRACT FROM AUTHOR]

Asymmetric side-chain engineering has been demonstrated to be an effective approach for modifying the solubility and morphology of non-fullerene small molecule acceptors (NF-SMAs). However, prior research has mostly concentrated on optimizing the length and branching locations of alkyl chains. Phenyl and cyclohexyl groups suspended on the side chains have been shown to be effective for tuning the crystallinity and self-assembly of symmetric organic molecules for efficient organic solar cells. To investigate the impact of the aromatic and non-aromatic ring side chains on the performance of asymmetric NF-SMAs, two asymmetric acceptors, Y-Ph4F and Y–CH4F , are designed with phenyl and cyclohexyl as two distinct side chains, respectively, in this work. Due to their common backbone, the two NF-SMAs exhibit similar absorption spectra and energy levels as determined by UV–vis absorption, cyclic voltammetry, and density functional theory calculations. Differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD) demonstrate that Y–CH4F with 4-cyclohexylbutyl side chains has stronger molecular packing and crystallinity in the solid state compared to Y-Ph4F with 4-phenylbutyl side chains. By pairing these NFAs with a well-known polymer donor PM6, both PM6:Y-Ph4F and PM6:Y-Ph4F-based organic solar cells (OSCs) achieve power conversion efficiencies (PCEs) of more than 15%. When fabricated with a 1 cm2 active area, the Y-Ph4F and Y–CH4F-based devices can also obtain exceptional PCEs of 15.05% and 14.10%, respectively. These findings suggest that the aromatic and non-aromatic ring side chains can effectively tune the molecular packing and crystallinity for efficient OSCs. [Display omitted] • Two novel asymmetric acceptors were synthesized and used in organic solar cells. • The impact of the side chains on the performance of acceptors was investigated. • Both acceptors show power conversion efficiencies over than 15%. • A new design approach for high-efficiency small molecule acceptors was developed. [ABSTRACT FROM AUTHOR]

Ductile-brittle transition temperature (DBTT) is a critical property of tungsten (W) materials for their application in a fusion reactor. The mechanism of ductile-brittle transition (DBT) has been the focus of debate in past decades. In this work, four-point bending test (4PBT) was performed to explore the controlling factors in different directions relative to the rolling direction. Opposite DBTT shifting trend in different directions after different recrystallization treatments indicated the diverse controlling factors of DBTT in rolled-W. Combined with microstructure analyses, the dislocation activity is considered the main controlling factor of DBTT in parallel to the rolling direction. For the samples perpendicular to the rolling direction, the change of DBTT is strongly correlated with the fracture mode. This study revealed the controlling factor of DBTT is anisotropic related to rolling direction after different recrystallization treatments. • Anisotropic controlling factors of DBT after different recrystallization treatments are related to the anisotropy of rolled-W. • The texture produced by rolling is more conducive to dislocation slip in RD direction. • The change of DBTT is strongly correlated with the fracture mode in TD direction. [ABSTRACT FROM AUTHOR]

Abstract: A series of ceria-based solid solution electrolytes, CoO and Sm2O3 codoped ceria Ce0.8Sm0.2−x Co x O2−δ (denoted as CSO for x =0 and CSC x for x =0.01–0.09), are synthesized via a carbonate co-precipitate method. The phase composition of the precursor is determined by XRD, EA and TG/DSC. The oxidation valence of Co in the samples calcined at different temperatures is probed by XPS and determined to be in +2 valence state at the temperature >1000°C. The sintering investigation demonstrates that the addition of Co promotes densification to occur at lower temperatures with a uniform grain growth. Impedance spectroscopy measurements indicate an improvement in the grain and the grain boundary conductivities for the samples with appropriate Co/Sm ratio. The optimal amount of Co additive is proved to be 7mol%. It shows that CSC0.07 exhibits higher conductivity (σ t =0.0538Scm−1 at 600°C) and lower activation energy (E a =0.567eV) compared with CSO and other CSC x . The results suggest that cobalt oxide could be used not only as an effective sintering aid but as a favorable dopant to ceria as well. [Copyright &y& Elsevier]

• Females are more attracted to mates in bright light under natural nocturnal light conditions. • The preference for longer calls of female frogs is not altered with ambient light intensity under natural nocturnal light conditions. • Neither dim nor bright light conditions affect the decision-making time of female frogs. Artificial light at night (ALAN) is a widespread anthropogenic stimulus that can significantly alter nocturnal animals' behavior, from migration to foraging to vocal communication. In the present study, we tested the hypothesis that the mate choice decisions of female serrate-legged small treefrogs (Kurixalus odontotarsus) were influenced by ambient light intensity. Standard two-speaker phonotaxis tests were conducted in a sound attenuating chamber. We set four light treatments (I-IV, from low to high) based on a range of light intensities from the maximum natural light at night (i.e., full moon) to that of the actual calling sites, which had artificial light. Contrary to our prediction, female frogs showed a preference for calls on the bright side in treatment I when they were exposed to identical stimuli. However, females preferred longer calls on the dim side to shorter calls on the bright side in this treatment. In addition, there were no significant effects of choice side, light treatment or their interaction on leave time or choice time. Our results suggest that females are more attracted to mates in bright light under natural nocturnal light conditions, but the preference for longer calls is not altered in serrate-legged small treefrogs. [ABSTRACT FROM AUTHOR]