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In this study, the axial compressive performance of steel–concrete–steel​ composite walls (SCSCWs) with novel dumbbell-shaped connectors (DSCs) was investigated. Six specimens were designed and tested, and the study parameters included the physical dimensions and arrangement schemes of DSCs. The failure mode, axial displacement, steel strain, and bearing capacity of the specimens were analyzed. The external steel plates exhibited local buckling, and the internal concrete was crushed. The variation in the physical dimensions of the DSC had little effect on the failure modes, and increasing the number of connectors improved the bearing capacity of the specimens. The axial load–displacement relationships of the SCSCWs were calculated considering the effects of local buckling and post-buckling behavior of steel faceplates in the constitutive relationship. The theoretical curves were in good agreement with the experimental results. A simplified formula for the bearing capacity was proposed, and the average ratio of the experimental to theoretical peak loads was 0.98, indicating that the simplified formula had high accuracy. ABAQUS software was used to simulate the axial behavior of SCSCWs. The simulated results were similar to those of the experiments, and the average ratio of the experimental bearing capacity to the corresponding simulated value was 0.99. Based on the benchmark model, further parameter analyses were conducted to study the effects of material strength and physical dimensions on the axial behavior of SCSCWs. Increasing the material strength and sectional thickness could increase the bearing capacity, and the failure mode was not affected. The theoretical initial stiffness of the SCSCWs was calculated, and the accuracy of the formulas was verified using the simulated results. [Display omitted] • Dumbbell-shaped connector was proposed for steel–concrete–steel composite wall. • Axial compressive behaviors of six specimens were experimentally investigated. • Local buckling and post-buckling behaviors were considered in formulas. • Axial load–displacement relationship was theoretically predicted by formulas. • Finite element models were established for further parameter analysis. [ABSTRACT FROM AUTHOR]

ACo 2 O 4 samples were synthesized as water oxidation catalysts. The samples were characterized by multiple experiments to confirm their uniform morphology, which belongs to the spinel structure (Fd3m space group). The catalytic activity of ACo 2 O 4 samples was investigated under photochemical, chemical, and electrochemical conditions; it follows the catalytic activity order NiCo 2 O 4 > CuCo 2 O 4 > ZnCo 2 O 4 . This activity sequence results from different doping metal ions in {Co 4 O 4 } motifs, which act as the active sites of water oxidation. Electrochemical impedance spectroscopy and other experimental data demonstrate that ACo 2 O 4 samples doped with different metal ions may influence the rate of charge and electron transport. Therefore, the catalytic activity of water oxidation followed the above order. [ABSTRACT FROM AUTHOR]

To date, it has not been elucidated whether the strategy method and the direct-response method lead to different behaviors in experiments of economic games. In this study, we investigate this issue under a multi-round setting of the capacity allocation game with both of the elicitation methods. In the first experiment (regular behavioral experiment), subjects are paired to make decisions in a laboratory through a computer network platform. In the second experiment (neuroimaging experiment), the functional magnetic resonance imaging (fMRI) technique is applied to observe similarities and differences in brain activities between the two elicitation methods. The results show that no significant difference is observed in the ordering behaviors between the two methods. Meanwhile, the neuroimaging data reveal that the strategy method induces comparable activations in similar brain regions, as does the direct-response method. Additionally, it is more likely that subjects adjust their decisions during the feedback phase, rather than during the decision phase. Our results indicate that, in multi-round game experiments without features such as emotion, the effect of the elicitation method is not likely to be exhibited. [ABSTRACT FROM AUTHOR]

Nanomaterials have great potential to influence the properties of cement-based materials due to their small particle size and large specific surface area. The influences of Nano-SiO2 (NS), gamma-nano-Al2O3 (GNA), alpha-nano-Al2O3 (ANA), and nano-TiO2 (NT) on the rheology and hydration kinetics of class G cement at 30 °C were investigated in this study. The nanomaterials were added in dry powder form at dosages of 1, 2, 3, 5, and 7% by weight of cement (bwoc), and their dispersion was accomplished using polycarboxylate superplasticizer (PCE) at a dosage of 1.6% bwoc. PCE provides a uniform dispersion of nanoparticles in the cement matrix, enhancing the efficiency of nanomaterials. The w/c ratio varied between 0.718 and 0.78 to form a constant-density slurry of 1.65 g/cm3. Our test results showed that NS and GNA caused significant increases in the rheology of the cement slurry, with this effect increasing with dosage, while ANA and NT tended to reduce the rheology of the slurry. Compared to a well-suspended and well-dispersed cement slurry generated by the use of PCE and diutan gum, all nanomaterials can accelerate early hydration by reducing the induction time, with GNA having the strongest influence, while NS was the only nanomaterial that further increased the long-term hydration heat release at 7 days. The stronger effect of NS and GNA on the cement slurry properties can be attributed to their higher chemical reactivity. The dosage effect on total hydration extent was relatively strong for ANA, NT, and NS from 3% to 5% but weak for GNA in the range from 3% to 7%. [ABSTRACT FROM AUTHOR]

In this study, six steel-concrete-steel composite wall (SCSCW) specimens have been designed and manufactured, and their out-of-plane flexural behaviors under combined axial and horizontal loads are experimentally studied. The study parameters include the connector arrangement scheme and applied axial load. The effects of these parameters on the failure modes, experimental load–displacement curves, bearing capacities, ductility coefficients, stiffness, energy dissipation capacities, and strain distributions of the specimens are analyzed. All specimens exhibit sectional flexural failure. The failure phenomena include the out-of-plane local buckling, concrete crushing, and welding fracture of the steel plates. These specimens show excellent ductility with an average ductility coefficient 2.27. The strength degradation coefficients of the specimens are >0.85. Increasing the number of connectors can restrict the local buckling of external steel plates, and the bearing capacities of the specimens are also improved. The connector arrangement scheme and axial load significantly influence the secant stiffness of the specimens during the initial stage of the experiments. When the connector arrangement schemes are identical, the higher the axial load, the better the energy dissipation capacity of the specimens. A simplified calculation model for the flexural capacity of SCSCWs is proposed considering the effects of local buckling and side plates, which has high accuracy and efficiency, and average ratio between the calculated and experimental peak loads is 0.96. A brief design example for the SCSCWs is provided to illustrate the design process considering the axial and out-of-plane loads. [Display omitted] • Quasi-static tests were performed to study the flexural behavior of composite walls. • A novel dumbbell-shaped connectors were used in six full-scaled specimens. • Local buckling of steel plates were considered in theory. • Theoretical formula for the bearing capacity of specimens was developed. [ABSTRACT FROM AUTHOR]

This paper presents axial compressive experiments of double-skin composite walls (DSCWs) with novel dumbbell-shaped connectors (DSCs) and traditional headed studs. The effects of the wall thickness, material strength, and diameter and number of the headed studs on the axial behavior of the DSCWs were analyzed. The failure modes of the specimens included the local buckling of the steel plates and compressive crushing of the concrete. The buckling position was between two adjacent rows of connectors. The experimental results demonstrated that the denser the arrangement of the connectors and the larger the diameter of the headed studs, the higher the critical buckling stress and axial bearing capacity of the specimens. The compressive stress–strain relationship of the steel material was determined considering the buckling and post-buckling behaviors of steel plates. According to the superposition principle, the theoretical load–displacement relationships of the five specimens were calculated, and the theoretical curves were in good agreement with the experimental results. The calculation formula for the axial bearing capacity of the specimens was introduced with some simplified assumptions, and the average value of the experiment/calculation ratio was 96.14%. ABAQUS software was used to simulate the DSCW specimens, and the failure modes of the models were in good agreement with the experiments. The average value of the experiment/simulation ratio for the peak load was 98.77%. Based on the verified benchmark model, the effects of four parameters on the compressive behavior of DSCWs were analyzed. [Display omitted] • Compressive experiments of five double-skin composite walls were conducted • A novel form of dumbbell-shaped connector was introduced • Local buckling and post-buckling behavior of steel plates were considered in theory • Theoretical formula for the bearing capacity of specimens was developed • FEM analysis was performed to study the effects of four parameters [ABSTRACT FROM AUTHOR]

Due to the low power consumption, self-powered ultraviolet (UV) photodetectors (PDs) are essential for the next-generation optoelectronic applications. In this work, it is pretty novel to demonstrate a self-powered photoelectrochemical (PEC) UV PD based on gallium nitride/cesium lead bromide (GaN/CsPbBr 3) core-shell nanowire (NW) heterojunctions. The GaN/CsPbBr 3 core-shell NW heterojunctions are formed efficiently by introducing the CsPbBr 3 quantum dots (QDs) with cubic phase onto the GaN NW surfaces. In the PEC PDs, CsPbBr 3 QDs can act as both light harvester and hole conductor. The appropriate energy level alignment could be a key reason contributing to the efficient increase of carrier separation and transport. Furthermore, it is found that the QD quantity and the spacing of GaN/CsPbBr 3 core-shell NWs can affect the PD performance significantly. With an appropriate quantity of CsPbBr 3 QDs, GaN/CsPbBr 3 core-shell NWs can not only enhance the photocurrent and responsivity significantly, but also accelerate the response speed by reducing the fall time. Thanks to the further introduction of the hydrogel, we can decrease the PD volume remarkably by working without water. It is also found that the hydrogel can accelerate the response speed significantly by reducing the path for carrier transport, which has the potential to develop the new practical PDs with high performance. It is very novel to demonstrate GaN/CsPbBr 3 core-shell nanowire heterojunctions in enhancing the ultraviolet responsivity of self-powered photoelectrochemical photodetector successfully. It is found that the hydrogel can not only decrease the photodetector volume by replacing water, but also accelerate the response speed significantly. Such a novel photodetector could pave a way for the development of next-generation optoelectronic devices. [Display omitted] • A detector based on GaN/CsPbBr 3 heterojunctions has been fabricated successfully. • CsPbBr 3 quantum dots can enhance the photocurrent by about 160%. • The quantity of CsPbBr 3 quantum dots can affect the photocurrent significantly. • The hydrogel can decrease the photodetector volume remarkably by replacing water. • It is found that the hydrogel can accelerate the response speed significantly. [ABSTRACT FROM AUTHOR]

A unique hexagonal sheet-shaped NiO/CoO/Fe2O3 composite with irregularly shaped nanoparticles was fabricated for the first time through a simple co-precipitation and hydrothermal method. The NiO/CoO/Fe2O3 composite was characterized by numerous techniques (TEM, HRTEM, PXRD, EDX, ICP-AES, BET, and XPS) to confirm its structure and composition. This structure of the NiO/CoO/Fe2O3 composite may enhance the photocatalytic and electrocatalytic performance for water oxidation. Compared with NiO, CoO and Fe2O3, the NiO/CoO/Fe2O3 composite exhibits a lower overpotential and a much smaller Tafel slope of 49 mV dec−1 for water oxidation. At the same time, the composite possesses beneficial ferromagnetic properties and superior stability; thus, it can be used repeatedly without any loss in activity. [ABSTRACT FROM AUTHOR]

Co3V2O8, a uniform hexagonal sheet-shaped morphology, for the first time acted as a robust catalyst for water oxidation. Under optimal photocatalytic conditions (photoirradiation at λ≥ 420 nm, Ru(bpy)3Cl2 as the photosensitizer, Na2S2O8 as the oxidant in borate buffer at pH = 8.5), the optimum apparent TOF of 10.9 μmol s−1 m−2 and O2 initial evolution rate of 31.7 μmol s−1 g−1 were achieved, which, to our best knowledge, are the highest values reported for heterogeneous photocatalytic water oxidation to date. Variables of the photocatalytic reaction, including catalyst concentrations, pH, dye concentrations and oxidant concentrations, were systemically studied. The oxygen atoms of the evolved oxygen came from water, as confirmed by isotope-labeled experiments. The stability of Co3V2O8 was tested and confirmed with multiple experiments (FT-IR, XRD, XPS), which indicated that Co3V2O8 is a stable catalyst under water oxidation. In addition, a mechanism of Co3V2O8 for the process of water oxidation was proposed. [ABSTRACT FROM AUTHOR]

Meaning in life contributes to psychological well-being. However, few studies have adopted an implicit theory approach to studying people's beliefs about the malleability of meaning in life. We propose the growth mindset of meaning in life (GMML) as the belief that meaning in life can be developed. In Study 1, we construct the Mindset of Meaning in Life Scale (MMLS) to measure GMML and demonstrate that GMML is distinct from growth mindset of intelligence and meaning in life. As predicted, GMML is positively associated with psychological well-being indicators, including life satisfaction and positive coping styles, and negatively correlated with ill-being measures such as depression and anxiety. In Study 2, tolerance of uncertainty was found to partially mediate the relationships between GMML and depression, anxiety, purpose in life, the presence of and search for meaning in life. Taken together, our findings suggest that GMML is a distinct construct relevant to individuals' well-being and meaning in life. [ABSTRACT FROM AUTHOR]

As a representative of third-generation semiconductors, silicon carbide serves as a new platform for quantum nano-optics with readable paramagnetic color centers such as silicon vacancies. The potential applications include biomedical imaging, quantum sensing and micro/nano environment detection. Color centers are usually prepared based on ion-irradiated substrates, then annealed at high temperature to increase the yield. Currently, annealing furnaces have been the main method to heat the substrate and achieve annealing of the whole sample. However, further exploration is still necessary for fine processing requirements such as specialized annealing regions with certain shapes. In this work, we applied femtosecond laser to achieve controllable annealing at micron scale, based on silicon carbide substrate after ion injection. The whole process of point, line and pattern annealing was realized. The annealing area demonstrates enhanced photoluminescence, attributed to silicon vacancy color centers. Raman and photoluminescence spectra reveal that the annealing effect is primarily influenced by the number of pulses per unit area. The mechanism of femtosecond laser annealing was introduced. Finally, the controllable annealing areas with various shapes were prepared based on the comprehensive optimal parameters (100 kHz pulse repetition frequency, 105 point annealing pulses, 10 μm/s line scanning speed). This annealing strategy demonstrates excellent stability and uniformity, as well as micron scale accuracy. Additionally, the excited state lifetime of silicon vacancy was extracted and quantified. The result means that femtosecond laser annealing enhances the optical properties and quantum application potential of color centers. This work can be further extended to other semiconductors as well as patterned modification of local surface/planes at some depth, and helpful to explore the mechanism and applications of femtosecond laser annealing. [ABSTRACT FROM AUTHOR]

In recent years, the rapid development of brain‐inspired neuromorphic systems has created an imperative demand for artificial photonic synapses that operate with low power consumption. In this study, a self‐driven memristor synapse based on gallium oxide (Ga2O3) nanowires is proposed and demonstrated successfully. This memristor synapse is capable of emulating a range of functionalities of biological synapses when exposed to 255 nm light stimulation. These functionalities encompass peak time‐dependent plasticity, pulse facilitation, and memory learning capabilities. It exhibits an ultrahigh paired‐pulse facilitation index of 158, indicating exceptional learning performance. The transition from short‐term memory to long‐term memory can be attributed to the remarkable relearning capabilities. Furthermore, the potential applications of the memristor synapse is showcased through the successful manipulation of a humanoid intelligent robot. Upon establishing artificial intelligence (AI) systems, the control commands originating from the synaptic device can drive the humanoid robot to perform various actions. Based on the memristor synapses, the autonomous feedback system of the humanoid robot facilitates a good collaboration between robotic actions and bio‐inspired light perception. Therefore, this research opens up an effective way to advance the development of neuromorphic computing technologies, AI systems, and intelligent robots that demand ultra‐low energy consumption. [ABSTRACT FROM AUTHOR]

Investigates the coadsorption of cyclohexane and oxygen of Pt(III) by HREELS and TDS. HREES spectra of cyclohexanone on the Pt(III) surface with preadsorption of oxygen; Formation of intermediate species and disappearance of the C=O stretching band after heating the coadsorbed surface; Cleavage of the molecule rings of dehydrogenation species.

Free chlorine (FC) species are important oxidants for organic synthesis and environmental remediation. However, due to competitive water oxidation, it's hard to obtain satisfied photoelectrochemical Faradic efficiency (FE) of FC via energetically unfavorable •Cl intermediate. Herein, we developed a non-radical strategy to realize efficient and stable FC production. High FE (86.2 %), high partial photocurrent density (2.8 mA/cm2) and excellent stability were achieved even under the conditions of diluted Cl (0.1 M) and neutral pH. Furthermore, compared with BVO, BVO@AgCl exhibited multi-fold faster rates for chlorine-mediated oxidations of styrene and arsenite with superior FEs (90.0 % vs. 59.4 %; 89.3 % vs. 47.3 %). Mechanistically, photogenerated holes are accumulated at AgCl sites (Cl+). FC is catalytically produced from the nucleophilic attack of Cl to Cl+, which bypasses •Cl intermediate and energetically outcompetes water oxidation. This work provides promising photoelectrochemical systems for highly efficient and stable production of FC, promoting high-value-added chemical synthesis and water treatment. [Display omitted] • A non-radical photoelectrochemical strategy to realize the efficient and stable FC production, by modifying BiVO 4 (BVO) photoanodes with AgCl sites (BVO@AgCl). • Relative to •Cl pathway on BVO, photogenerated holes are accumulated at AgCl sites, and FC is catalytically produced from the nucleophilic attack of Cl to the oxidized AgCl sites (Cl+) in a non-radical manner, which is energetically outcompetes water oxidation to •OH. [ABSTRACT FROM AUTHOR]

Fracture is a key factor for high and stable reservoir production in Ordovician carbonatite fracture-cavity reservoirs in the Tahe Oilfield. In this paper, we firstly identify and statistically analyse the medium to small scale fractures in the Ordovician carbonate reservoirs of the Tarim Basin Tahe Oilfield by using a large amount of thin section, core, and imaging logging data. Secondly, the R/S-FD numerical analysis method is introduced to realize the calculation of fracture development segments based on different conventional logging curves, and then the cumulative multiplication method is used to realize the quantitative prediction of fracture development segments in a single well under the constraints of multiple curves. Finally, the fracture identified by the core and FMI imaging logging data was verified with the prediction results of the R/S-FD numerical analysis method to determine the applicability and accuracy of the method in fracture prediction. The results show that Structural fractures predominate in the study area, where high angle, shear fractures are mainly developed; Of the different types of conventional logging curves, the AC, RS and RD curves are highly sensitive and similar to the fracture development segments in carbonate reservoirs. Although GR is sensitive to fractures, it is too different from the rest of the curves to be applied in the comprehensive analysis. DEN and CAL curves are relatively weak in terms of fracture sensitivity and are not suitable to be applied in fracture prediction. The results of R/S-FD fracture identification for different curves show that the method is effective in identifying single, high-angle fractures and multiple, medium-angle fractures, and is inadequate in identifying low-angle and horizontal fractures. Comparison and validation of the R/S-FD fracture identification curves with cores and imaging logs show that the comprehensive fracture identification probability of the method can reach 71.6%, which proves that the method has a strong ability to identify single-well tectonic fractures in carbonate reservoirs. The application of this method to fracture prediction in Ordovician carbonate reservoirs is of great significance for the evaluation of fractured carbonate reservoirs in oil and gas exploration. [ABSTRACT FROM AUTHOR]

The rapid proton exchange between surface bridging hydroxyls and adsorbed molecules on TiO 2 was investigated, which was modulated by surface healing. • The interactions of adsorbed molecules with the surface sites on TiO 2 were investigated. • The surface hydroxyls, defects and Ti sites were modulated by surface healing process. • The rapid proton exchange between the defect-involved bridging hydroxyl groups and the adsorbed molecules was confirmed. • The increase in non-defective surface sites enhanced ζ potential and hindered interfacial electron transfer activity. Understanding the interactions of adsorbed molecules with TiO 2 surfaces is important for diverse applications, such as photocatalysis and self-cleaning surfaces. Herein, we investigated the interactions of adsorbed molecules with surface sites on TiO 2. The 1H NMR spectra showed that surface healing led to an interesting upfield shift in the chemical shifts of hydroxyls of adsorbed molecules, which is caused by rapid proton exchange between the defect-involved bridging hydroxyls and adsorbed molecules. Infrared spectroscopy confirmed that surface healing decreases the number of surface hydroxyl groups and enhances the number of non-defective surface Ti sites required for methanol adsorption. Therefore, we proposed that undissociative adsorption of methanol is the preferential interaction mode with the non-defective sites of the TiO 2 surface but dynamic equilibrium between dissociative and undissociative adsorption exists around surface defect sites. The increase in non-defective surface sites enhanced the surface ζ potential and hindered interfacial electron transfer activity. [ABSTRACT FROM AUTHOR]

• Tune the luminescence spectra of InGaN nanocolumns by a low-cost method. • Uniform microhole arrays show the ability in tuning the luminescence spectra. • Microhole size and flat area are found to have obvious effects in spectra tuning. In this paper, the molecular beam epitaxy of InGaN nanocolumns on silicon-based microhole arrays has been investigated experimentally. A low-cost method has been designed, which contains the processes of photolithography and wet etching. Tuning uniform microhole arrays show the ability in modulating the luminescence spectra of InGaN nanocolumns, which could lead to the modulation of tristimulus coordinates and correlated color temperatures. Due to the shadow effect, it is found that the size of microholes and the area of flat Si surface have more obvious effects, while the configuration of microhole arrays has limited effect on the modulation of peak wavelength. [ABSTRACT FROM AUTHOR]

Because of wide range of applications, the flexible artificial synapse is an indispensable part for next-generation neural morphology computing. In this work, we demonstrate a flexible synaptic device based on a lift-off (In,Ga)N thin film successfully. The synaptic device can mimic the learning, forgetting, and relearning functions of biological synapses at both flat and bent states. Furthermore, the synaptic device can simulate the transition from short-term memory to long-term memory successfully under different bending conditions. With the high flexibility, the excitatory post-synaptic current of the bent device only shows a slight decrease, leading to the high stability. Based on the experimental conductance for long-term potentiation and depression, the simulated three-layer neural network can achieve a high recognition rate up to 90.2%, indicating that the system comprising of flexible synaptic devices could have a strong learning-memory capability. Therefore, this work has a great potential for the development of wearable intelligence devices and flexible neuromorphic systems. [ABSTRACT FROM AUTHOR]

Taking a resource perspective, we examined the relationships between employee authenticity and work attitudes/behaviors, focusing especially on the mediating role of psychological capital and the moderating role of leader authenticity. Data were collected with a three-wave survey administered to a sample of 588 employees from a biological manufacturing company in eastern China. Our results showed that employee authenticity can promote positive work attitudes/behaviors and inhibit negative ones among employees. The underlying mechanism is that employee authenticity can be converted into psychological capital, which is a positive psychological resource, and can further shape employee work attitudes and behaviors. Additionally, leader authenticity, as a job resource in the work environment, strengthens this conversion. The theoretical and practical implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Broadband ultraviolet (BUV) photodetectors responding to the multiband spectrum can effectively reduce false alarm rates and improve the accuracy and versatility of detection systems in various situations. A high‐responsivity BUV photodetector based on vertical Ga2O3/GaN nanowire array is proposed and demonstrated. Ga2O3/GaN nanowires are obtained by partially thermally oxidizing GaN nanowires grown by molecular beam epitaxy and used to combine with a monolayer graphene film to form graphene/Ga2O3/GaN heterojunction. Moreover, the oxidation mechanism of GaN nanowires is further investigated by the developed thermal oxidation model. The fabricated devices exhibit excellent performance with a broadband spectral response of exceeding 550 A W−1 at −5 V and a fast‐response speed in the millisecond range, which can be attributed to the optical properties of vertical nanowire array structure and the internal gain mechanism of graphene/Ga2O3/GaN heterojunction. A high‐responsivity broadband ultraviolet photodetector based on vertical Ga2O3/GaN nanowire array is proposed and demonstrated. The nanowires are obtained by partial thermal oxidation and form a graphene/Ga2O3/GaN heterojunction. The fabricated devices exhibit a great broadband spectral response with the high responsivity exceeding 550 A W−1. Meanwhile, an oxidation model is proposed to explain the crystalline transformation of GaN nanowires in thermal oxidation. [ABSTRACT FROM AUTHOR]

In the electrodes of spent lithium-ion batteries, graphite, due to its layered structure and crystalline composition, presents significant recyclable value, yet it has not been fully utilized. This study proposes a modified mechanical exfoliation method (MEM), which employs leaching-drying pretreatment to transform waste graphite into two-dimensional graphene. Three drying methods were evaluated, among which freeze drying was found to be the most conducive for exfoliation. Pneumatic drying, being basic and simple, did not exhibit any special effects that benefit exfoliation. XRD results showed that leaching restores the lamellar structure of graphite, with peak intensity (× 105) increasing from 6.5 to 8.9–10.1. XPS analysis revealed that vacuum roasting drying leads to dehydration condensation of hydroxyl groups between layers, resulting in the obtained graphite having the best dehydration effect and the lowest oxygen content, at only 1.89%, but this enhances interlayer forces, which is counterproductive for exfoliation. In contrast, freeze drying, through the volumetric expansion caused by the freezing of water, disrupts the interlayer forces, achieving an interlayer spacing of 337.5 nm, which facilitates the exfoliation of graphene. This was confirmed by TEM results. This method effectively overcomes the problem of impurity contamination in waste graphite, providing a new approach for the high-value utilization and green recycling of graphite in spent lithium batteries. [Display omitted] • Dehydration condensation of vacuum drying results in a tighter graphite layer. • Volume expansion from water freezing can break the interlayer force of graphite. • The modified MEM can remove impurities and avoid secondary contamination. • Graphite wastes in spent LIBs can be environmentally upcycled into 2D graphene. [ABSTRACT FROM AUTHOR]

Background: Sesquiterpenes are designated as a large class of plant-derived natural active compounds, which have wide applications in industries of energy, food, cosmetics, medicine and agriculture. Neither plant extraction nor chemical synthesis can meet the massive market demands and sustainable development goals. Biosynthesis in microbial cell factories represents an eco-friendly and high-efficient way. Among several microorganisms, Saccharomyces cerevisiae exhibited the potential as a chassis for bioproduction of various sesquiterpenes due to its native mevalonate pathway. However, its inefficient nature limits biosynthesis of diverse sesquiterpenes at industrial grade. Results: Herein, we exploited an artificial synthetic malonic acid-acetoacetyl-CoA (MAAC) metabolic pathway to switch central carbon metabolic flux for stable and efficient biosynthesis of sesquiterpene-based high-density biofuel precursor in S. cerevisiae. Through investigations at transcription and metabolism levels, we revealed that strains with rewired central metabolism can devote more sugars to β-caryophyllene production. By optimizing the MVA pathway, the yield of β-caryophyllene from YQ-4 was 25.8 mg/L, which was 3 times higher than that of the initial strain YQ-1. Strain YQ-7 was obtained by introducing malonic acid metabolic pathway. Combing the optimized flask fermentation process, the target production boosted by about 13-fold, to 328 mg/L compared to that in the strain YQ-4 without malonic acid metabolic pathway. Conclusion: This designed MAAC pathway for sesquiterpene-based high-density biofuel precursor synthesis can provide an impressive cornerstone for achieving a sustainable production of renewable fuels. [ABSTRACT FROM AUTHOR]

Due to the emerging requirements of miniaturization and multifunctionality, monolithic devices with both functions of lighting and detection are essential for next-generation optoelectronic devices. In this work, based on freestanding (In,Ga)N films, we demonstrate a monolithic device with two functions of lighting and self-powered detection successfully. The freestanding (In,Ga)N film is detached from the epitaxial silicon (Si) substrate by a cost-effective and fast method of electrochemical etching. Due to the stress release and the lightening of the quantum-confined Stark effect (QCSE), the wavelength blueshift of electroluminescent (EL) peak is very small (<1 nm) when increasing the injection current, leading to quite stable EL spectra. On the other hand, the proposed monolithic bifunctional device can have a high ultraviolet/visible reject ratio (Q = 821) for self-powered detection, leading to the excellent detection selectivity. The main reason can be attributed to the removal of Si by the lift-off process, which can limit the response to visible light. This work paves an effective way to develop new monolithic multifunctional devices for both detection and display. [ABSTRACT FROM AUTHOR]

Background: The triglyceride-glucose (TyG) index is a reliable alternative biomarker of insulin resistance (IR). However, whether the TyG index has prognostic value in critically ill patients with coronary heart disease (CHD) remains unclear. Methods: Participants from the Medical Information Mart for Intensive Care III (MIMIC-III) were grouped into quartiles according to the TyG index. The primary outcome was in-hospital all-cause mortality. Cox proportional hazards models were constructed to examine the association between TyG index and all-cause mortality in critically ill patients with CHD. A restricted cubic splines model was used to examine the associations between the TyG index and outcomes. Results: A total of 1,618 patients (65.14% men) were included. The hospital mortality and intensive care unit (ICU) mortality rate were 9.64% and 7.60%, respectively. Multivariable Cox proportional hazards analyses indicated that the TyG index was independently associated with an elevated risk of hospital mortality (HR, 1.71 [95% CI 1.25–2.33] P = 0.001) and ICU mortality (HR, 1.50 [95% CI 1.07–2.10] P = 0.019). The restricted cubic splines regression model revealed that the risk of hospital mortality and ICU mortality increased linearly with increasing TyG index (P for non-linearity = 0.467 and P for non-linearity = 0.764). Conclusions: The TyG index was a strong independent predictor of greater mortality in critically ill patients with CHD. Larger prospective studies are required to confirm these findings. [ABSTRACT FROM AUTHOR]