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Three-dimensional (3D) printing, otherwise known as additive manufacturing in a non-technical context, is becoming increasingly popular in the field of dentistry. As an essential step in the 3D printing process, postwashing with organic solvents can damage the printed resin polymer and possibly pose a risk to human health. The development of water-washable dental resins means that water can be used as a washing agent. However, the effects of washing agents and washing times on the mechanical and biocompatibility properties of water-washable resins remain unclear. This study investigated the impact of different washing agents (water, detergent, and alcohol) and washing time points (5, 10, 20, and 30 min) on the flexural strength, Vickers hardness, surface characterization, degree of conversion, biocompatibility, and monomer elution of 3D printed samples. Using water for long-term washing better preserved the mechanical properties, caused a smooth surface, and improved the degree of conversion, with 20 min of washing with water achieving the same biological performance as organic solvents. Water is an applicable agent option for washing the 3D printing water-washable temporary crown and bridge resin in the postwashing process. This advancement facilitates the development of other water-washable intraoral resins and the optimization of clinical standard washing guidelines. [ABSTRACT FROM AUTHOR]

Intrinsically stretchable organic optoelectronic devices have been demonstrated for board applications such as tissue-like patches, medical prosthetic apparatus, biomimetic visual system and interactive soft robots. However, there are huge barriers to implementing high-performance intrinsically stretchable organic optoelectronic devices and integrated circuits. In this perspective, a brief overview of recent advances in several significant intrinsically stretchable organic optoelectronic devices and arrays is provided. Furthermore, the overlooked challenges and our viewpoint on the future development of intrinsically stretchable organic optoelectronic technologies are emphasized. [Display omitted] [ABSTRACT FROM AUTHOR]

Comprehensive Summary: 2D covalent organic framework (2D‐COF), a modular three‐dimensional material, is easily influenced by the component module. The assembly of different functionalized modules gives 2D‐COF unique performance. The modular structure not only allows for customization but also allows for variety, which gives 2D‐COF a wide range of functions. Hence, many building blocks with catalytic, ligand, semiconductor, luminescent, and redox centers are integrated into the COF scaffold. The connection and assembly of such modules determine the nature of the final block material. The intra‐layer connections of the modules form a monolayer mesh chemical structure, and the subsequent stacking of the monolayer mesh structure produces the final crystalline porous material—2D‐COF. This review describes in detail the potential of COF materials as optoelectronic materials and our understanding of optoelectronic processes, starting from monolayer reticulation chemistry to final 3D stacked structures, thus establishing a new paradigm for the rational design of well‐defined novel 2D‐COF optoelectronic materials and devices. [ABSTRACT FROM AUTHOR]

We study dynamic processes through which the scalar hair of black holes is generated or detached in a theory with a scalar field non-minimally coupled to Gauss-Bonnet and Ricci scalar invariants. We concentrate on the nonlinear temporal evolution of a far-from-equilibrium gravitational system. In our simulations, we choose the initial spacetime to be either a bald Schwarzschild or a scalarized spherically symmetric black hole. Succeeding continuous accretion of the scalar field onto the original black hole, the final fate of the system displays intriguing features, which depend on the initial configurations, strengths of the perturbation, and specific metric parameters. In addition to the scalarization process through which the bald black hole addresses scalar hair, we observe the dynamical descalarization, which removes scalar hair from an original hairy hole after continuous scalar field accretion. We examine the temporal evolution of the scalar field, the metrics, and the Misner-Sharp mass of the spacetime and exhibit rich phase structures through nonlinear dynamical processes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Vitis vinifera L. cv. Syrah grapevines in most Chinese viticulture regions generally have compact clusters that increase the susceptibility to diseases and inhibit coloration of the inner berries. Gibberellic acid (GA3) is a plant growth regulator that is widely used during grape cultivation to elongate the rachis, control fruit set, and decrease cluster compactness. In this study, Syrah grapevines were treated with GA3 before flowering in 2019 and 2020 to determine the optimal GA3 treatment concentrations and times for decreasing bunch compactness, while minimizing the negative effects on the wine grape cluster weight. RESULTS: Pre‐flowering GA3 applications at 3, 5, and 7 mg L−1, especially treatment at 20 days before flowering, decreased Syrah grape bunch compactness by decreasing the fruit set rate and promoting bunch elongation, with minimal adverse effects on the healthy grape cluster weight in both years. The 7 mg L−1 GA3 treatment at 20 days before flowering significantly increased reducing sugar, total phenolic, tannin, and total anthocyanin contents of Syrah grape berries in 2019 and 2020. Moreover, high‐performance liquid chromatography–electrospray ionization–tandem mass spectrometry, hierarchical cluster, and principal component analysis results indicated GA3 applications before flowering (3, 5, and 7 mg L−1) significantly affected the accumulation of different anthocyanins in Syrah grape berries. Notably, the application of 7 mg L−1 GA3 at 20 days before flowering resulted in the highest anthocyanin content. CONCLUSION: Pre‐flowering gibberellin application can decrease bunch compactness and improve the quality of Syrah grape berries. These findings reflect the potential utility of gibberellin treatments for decreasing cluster compactness and increasing the quality of wine grapes. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Robust 2‐mm 6061‐T6/SUS304 butt plates were obtained using laser‐MIG hybrid welding‐brazing technology. The fatigue properties and fracture behavior of Al/steel welding‐brazing joints were first discussed. Due to the change in the fracture mechanism, the weld reinforcement improved the fatigue strength, which was higher than that of the Al/steel joints using the solid‐state welding method. This strengthening effect was very different from traditional fusion welding joints with reinforcement. The fatigue test results showed that the fatigue strength of the Al/steel joints with reinforcement reached about 105 MPa at 106 cycles. After removing the weld reinforcement, the fatigue strength of the Al/steel joints reduced significantly to 55 MPa. The existence of reinforcement also led to different fatigue fracture behaviors. In the Al/steel joints with reinforcement, the fatigue fracture mode changed with increasing cyclic stress load, and the fatigue crack initiation zone was inclined to begin at the weld toe and then propagated along the weld at a lower stress load. Fatigue crack initiation sites moved to the aluminum weld near the interface and spread along with the IMC layer and the aluminum weld at higher stress loads. After removing the weld reinforcement, only the interface fracture mode was found. Highlights: A high strength Al/steel welding‐brazing joint (up to 200 MPa) is obtained.The weld reinforcement has a positive effect on the fatigue strength.The existence of the weld reinforcement leads to different fatigue fracture modes.Pores inside the aluminum weld are likely to be the fatigue crack initiation zone. [ABSTRACT FROM AUTHOR]

• Fatigue crack propagation (FCP) in different micro-zones of aluminum/steel joints was investigated. • Single-edge notched tensile (SENT)-interface showed the highest FCP rate and crack threshold. • The FCP path of SENT-weld was deflected toward the heat-affected zone. • SENT-weld deflection is due to the effects of microstructure and micro-performance. Research on fatigue damage of aluminum/steel dissimilar joints is critical to ensure the reliability of multi-material lightweight structures. In this study, the fatigue crack propagation (FCP) characteristics of the interface, weld, and heat-affected zone (HAZ) of aluminum/steel laser-metal inert gas (MIG) fusion-brazed joints were investigated. Additionally, the influencing role of the microstructure of different micro-zones on the FCP behaviors was discussed. Single-edge notched tensile (SENT) specimens of the interface region exhibited a higher crack growth rate and crack threshold than SENT-weld and SENT- HAZ specimens due to the highly hard and brittle nature of the intermetallic compounds (IMC) at the aluminum/steel interface. Moreover, the fatigue fracture surface of SENT-interface specimens showed a brittle fracture pattern without fatigue striation characteristics, which was different from aluminum/steel solid-state and traditional aluminum alloy welded joints. Electron backscatter diffraction (EBSD) analysis results revealed that the synergistic effects of grain size, sub-grain boundaries, and micro-performance all contributed to the crack deflection of SENT-weld at a large angle to the HAZ, thereby resulting in more optimized crack resistance in the weld zone. [ABSTRACT FROM AUTHOR]

As a kind of energy-saving and micro-hydropower utilization device, pump as turbine (PAT) is simple to construct with low operation and maintenance costs, which is widely used in the energy-consuming industrial processes and micro-hydro power generation. The variation law of blade angle from blade inlet to outlet has the characteristics of uncertainty and diversity, which determines the middle bending shape of the blade and has a direct impact on the fluid. Different blade bending shapes form different wrap angles on the premise of impeller outlet and inlet angles kept invariable. To investigate how the blade angle distribution affects the performance, four different impellers were created and analyzed based on computational fluid dynamics method. This paper investigates the effect of blade bending shapes on the performance characteristics, unsteady characteristics and energy loss of PAT. The numerical result shows due to the small blade wrap angle, the best efficiency of scheme 2 is the lowest among the four schemes, while the best efficiency of scheme 4 is the highest. The appropriate blade bending shape is beneficial to reduce the enstrophy dissipation and improve the efficiency and operating stability of PAT. These findings provide reference points for optimizing the blade profile in PAT. • Different angle distribution profiles from the blade inlet to the blade outlet will form different blade camber shapes. • Four PAT's impellers with different blade bending shapes are designed and investigated by a verified CFD method. • The appropriate blade bending shape can improve the operation stability and the unsteady flow characteristics of PAT. • It is beneficial to improve the PAT's performance that the blade camber shape is mainly concentrated in the blade middle. [ABSTRACT FROM AUTHOR]

The evolutionary success in information technology has been sustained by the rapid growth of sensor technology. Recently, advances in sensor technology have promoted the ambitious requirement to build intelligent systems that can be controlled by external stimuli along with independent operation, adaptivity, and low energy expenditure. Among various sensing techniques, field-effect transistors (FETs) with channels made of two-dimensional (2D) materials attract increasing attention for advantages such as label-free detection, fast response, easy operation, and capability of integration. With atomic thickness, 2D materials restrict the carrier flow within the material surface and expose it directly to the external environment, leading to efficient signal acquisition and conversion. This review summarizes the latest advances of 2D-materials-based FET (2D FET) sensors in a comprehensive manner that contains the material, operating principles, fabrication technologies, proof-of-concept applications, and prototypes. First, a brief description of the background and fundamentals is provided. The subsequent contents summarize physical, chemical, and biological 2D FET sensors and their applications. Then, we highlight the challenges of their commercialization and discuss corresponding solution techniques. The following section presents a systematic survey of recent progress in developing commercial prototypes. Lastly, we summarize the long-standing efforts and prospective future development of 2D FET-based sensing systems toward commercialization. [ABSTRACT FROM AUTHOR]

The latent space of pre-trained generative adversarial networks (GANs) is rich in semantic information, which often becomes highly entangled. It is crucial to identify semantic directions within this latent space, as these directions correlate with image attributes and are vital for image editing tasks. Existing methods for semantic discovery usually involve labor-intensive procedures such as manual labeling and training attribute classifiers, which limits their practicality. In response to this issue, the paper proposes the Optimal Transport-based Unsupervised Semantic Disentanglement (OTUSD) algorithm. This novel method efficiently uncovers semantic directions in the latent space of GANs by utilizing the concepts of manifold learning and optimal transport (OT) theory. OTUSD applies singular value decomposition (SVD) to the OT matrix that links latent codes to generated images. This process yields singular vectors that correspond to semantically meaningful directions. Unlike traditional methods, OTUSD bypasses the need for time-consuming labeling and training processes, thus enhancing efficiency and revealing a wider array of semantically meaningful directions. Experimental results demonstrate the effectiveness of OTUSD in discovering semantic directions from several state-of-the-art GAN models, including StyleGAN, StyleGAN2, and BigGAN. This performance emphasizes the potential applicability of OTUSD to image editing and other related tasks, and illuminates its value in harnessing the manifold learning and OT mapping capabilities inherent in GANs for semantic disentanglement. The implementation code is available at https://github.com/LuckAlex/OTUSD. • Introduced the unsupervised algorithm to disentangle semantics in GANs. • Outperforms other methods in identifying variation factors. • Increased efficiency in representing GAN generation processes. • Validated through experiments with state-of-the-art GAN models. • Broad applicability for image editing and beyond. [ABSTRACT FROM AUTHOR]

This article discusses the recent progress in the development of high-mobility polymer semiconductors with various functionalities. These semiconductors have advantages such as easy solution processing, large-area manufacturing, mechanical strength, and flexibility. The article focuses on the integration of high mobility with stretchability, strong luminescence, photolithography patterning, and efficient thermoelectric conversion. The challenges and future directions in this field are also discussed. The research is supported by various funding sources. [Extracted from the article]

• DIC technology is used to study the quasi-static and dynamic fracture mechanisms. • Strain concentration is the main reason for quasi-static and dynamic fracture of aluminum/steel joints. • FEM results explained the different fatigue fracture behaviors of aluminum/steel joints with reinforcement. • The weld reinforcement has an important effect on the performance and fracture behavior. • It is important to retain proper weld reinforcement of aluminum/steel joints in practical applications. The primary focus of this study was the fracture mechanism of aluminum/steel laser-arc welded-brazed joints under quasi-static tensile and dynamic fatigue conditions. Digital image correlation (DIC) was applied to record the tensile and fatigue fracture process, while finite element method (FEM) was employed to analyze stress distributions during fatigue tests. The tensile results indicated that the weld reinforcement changed the strain evolution and significantly improved mechanical properties of aluminum/steel joints. During fatigue tests, the weld reinforcement enhanced fatigue properties and changed the joint geometry of aluminum/steel joints, leading to the emergence of distinct failure behaviors. At larger stress loads, the maximum cyclic stress on the interface surpassed the interfacial bonding strength, which resulted in a gradual shift of strain concentration from the weld toe to the interface. At smaller stress loads, the interfacial region exhibited tremendous crack resistance, and strain gradually accumulated in the weld toe, which led to fatigue damage. Interestingly, the strain in the interfacial region became more significant during the fatigue process after removing the weld reinforcement. Overall, this study shed light on the fracture mechanism of aluminum/steel joints under different loading conditions. Knowledge of this mechanism is essential for developing reliable aluminum/steel structures. [ABSTRACT FROM AUTHOR]

Cardiac ventricular arrhythmia triggered by acute myocardial infarction (AMI) is a major cause of sudden cardiac death. We have reported previously that an increased serum level of circular RNA CDR1as is a potential biomarker of AMI. However, the possible role of CDR1as in post-infarct arrhythmia remains unclear. This study in MI mice investigated the effects and underlying mechanism of CDR1as in ventricular arrhythmias associated with MI. We showed that knockdown of CDR1as abbreviated the duration of the abnormally prolonged QRS complex and QTc intervals and decreased susceptibility to ventricular arrhythmias. Optical mapping demonstrated knockdown of CDR1as also reduced post-infarct arrhythmia by increasing the conduction velocity and decreasing dispersion of repolarization. Mechanistically, CDR1as led to the depletion of NAD+ and caused mitochondrial dysfunction by directly targeting the NAMPT protein and repressing its expression. Moreover, CDR1as aggravated dysregulation of the Na V 1.5 and Kir6.2 channels in cardiomyocytes, a change which was alleviated by the replenishment of NAD+. These findings suggest that anti-CDR1as is a potential therapeutic approach for ischemic arrhythmias. [Display omitted] • The increase of CDR1as expression in MI induced arrhythmias by compromising cardiac mitochondrial function and NAD+ homeostasis. • CDR1as directly interacts with NAMPT protein, leading to abnormal cardiac conduction velocity and APD dispersion. • NAD+ salvage capacity is important for the expression of Na V 1.5 and Kir6.2 channels in cardiomyocytes after MI. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are a type of crystalline porous polymer composed of light elements through strong covalent bonds. COFs have attracted considerable attention due to their unique designable structures and excellent material properties. Currently, COFs have shown outstanding potential in various fields, including gas storage, pollutant removal, catalysis, adsorption, optoelectronics, and their research in the sensing field is also increasingly flourishing. In this review, we focus on COF‐based sensors. Firstly, we elucidate the fundamental principles of COF‐based sensors. Then, we present the primary application areas of COF‐based sensors and their recent advancements, encompassing gas, ions, organic compounds, and biomolecules sensing. Finally, we discuss the future trends and challenges faced by COF‐based sensors, outlining their promising prospects in the field of sensing. [ABSTRACT FROM AUTHOR]

Under the Belt and Road Initiative (BRI), China and BRI countries mutually benefited from the trade in the economy. Meanwhile, considerable CO 2 emissions were embodied in the trade, possibly putting pressure on China's "3060" target of peaking CO 2 emissions before 2030 and achieving carbon neutrality by 2060. Yet less is known about the heterogeneous impacts of BRI-induced trade on China, especially at the provincial level. This study quantifies the provincial mismatch of CO 2 emissions and economic benefits induced by BRI countries' final demand using the latest linked multiregional input-output model. We found that provinces in China paid around 0.24–7.01 Mt embodied CO 2 emissions to obtain per unit billion USD dollars in fulfilling BRI countries' final demand. Regarding the sectoral patterns, embodied CO 2 emissions of electricity, gas, and water sector accounted for the largest proportion (more than 50%) for 60% of provinces. Other services sector greatly contributed to each province's economic benefits. We also found that only 15.2% of these embodied CO 2 emissions could be mitigated even though upgrading the technology levels of all sectors in backward provinces to China's average level. This indicated that measures relying on the current technology are far from enough for achieving the carbon targets. Therefore, it is urgent to deepen the technology innovation and reform of emission sectors in the short term. In the long run, seeking new long-term pathways of emission reduction, such as optimizing trade structure, is conducive to promoting the sustainable development of BRI and the "3060" realization. [Display omitted] • Assessment of embodied provincial CO 2 emissions and value-added under BRI. • Scenario analysis is conducted to assess emission reduction potential under BRI. • Developed provinces got more wealth at similar costs of CO 2 emissions in China. • Upgrading sectoral technological levels to China's average level is insufficient. [ABSTRACT FROM AUTHOR]

• Long-period fiber grating based linearly polarized mode converter operating at a dispersion turning point has been demonstrated. Such mode converter can realize broadband mode conversion. • A broadband and controllable linearly polarized OAM modes generator using a single long-period fiber grating followed by a length of few-mode polarization-maintaining fiber has been demonstrated. • A simple approach was proposed to tunable the linearly polarized OAM mode, the phase difference of the two linearly polarized modes was continually turned by strain, the OAM mode can be smoothly tunable between ±1 order. We demonstrate a broadband and stable linearly polarized mode converter by inscribing long-period grating (LPG) in few-mode polarization-maintaining fibers (FPMFs). The operating wavelength of the mode converter at 1.0- and 1.5- μm waveband has been achieved by using PMF with different cut-off wavelengths. Theoretical and experimental demonstrated broadband linearly polarized mode conversion can be achieved with a maximum 10 dB bandwidth of 140- and 189- nm at 1.0- and 1.5- μm waveband respectively due to the turning point coupling mechanism. Then, we propose and demonstrate a controllable linearly polarized orbital angular momentum (LP-OAM) mode generator using a single LPG-based mode converter and a length of FPMF. The LP-OAM mode is produced by turning axial strain and can be smoothly switched between ± 1 order. Our all-FPMF based grating fabrication offers a new option towards a stable and broadband polarized mode converter and LP-OAM mode generator for application in a few-mode fiber laser and communication system. [ABSTRACT FROM AUTHOR]

[Display omitted] • Circulating fluidized bed combustion fly ash provided calcium source for microbially induced calcium carbonate precipitation. • Circulating fluidized bed combustion fly ash underwent hydrate reaction. • The hydration product C-S-H promoted CaCO 3 precipitation and contributed to strength. • The approach has the potential of application in geotechnical engineering field. [ABSTRACT FROM AUTHOR]

[Display omitted] • P. mucilaginosus destructed anhydrite of circulating fluidized-bed fly ash. • Active SiO 2 and Al 2 O 3 was increased by P. mucilaginosus. • Pozzolanic activity was improved by P. mucilaginosus. • P. mucilaginosus promoted fly ash hydration and ettringite earlier formation. • The compatibility of circulating fluidized-bed fly ash with cement was improved. The present investigation reports an eco-friendly biotechnology applying Paenibacilllus mucilaginosus (P.m), a silicate solubilizing bacteria, to activate pozzolanic activity of CFA. The results show SiO 2 and Al 2 O 3 dissolution rate of CFA treated by P.m and its Ca2+ absorption capacity in saturated Ca(OH) 2 solutions are increased compared to raw CFA indicating that pozzolanic reactivity of CFA is improved by P.m. One reason is destruction of the anhydrite coating layer of CFA particles surface through P.m erosion. Another reason is promotion of SiO 2 dissolution caused by deformation and destruction of Si-O-Si (Al) bonds by P.m. Carbonic anhydrase activity of P.m is one of the main factors involved in dissolution of SiO 2 , which also induces CaCO 3 mineralization. The hardening characteristics and hydration products of CFA-15% lime system with different content of P.m further confirm the effects of P.m on pozzolanic activity of CFA. 40% P.m incorporation is conducive to promote CFA hydration, ettringite earlier formation and bio-mineralization, thereby improving the mechanical properties of hardened mortar. Incorporation of 40% P.m in cement blended with CFA results in that CFA content is increased by 5–20% and the 28d strength improved by 11.5–23.9 MPa. This is the first report of microbial activation of CFA pozzolanic activity. [ABSTRACT FROM AUTHOR]

6-mm 6061-T6/SUS304 butt joints were obtained successfully with a breakthrough through a deep-penetration welding-brazing process using a laser hybrid metal inert gas (MIG). The laser powers were optimized to obtain a sound joint with good formation. The quality of joints was evaluated via tensile tests. Moreover, the morphology and thickness of the intermetallic compound (IMC) layer along Al/steel interface were also studied via Scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the spreading degree on the steel side of the molten metal was improved with increasing laser power, and a sound joint without visible defects was obtained when the laser power was 4150 W. Double IMC layers consisting of η-Fe 2 (Al, Si) 5 and θ-Fe(Al, Si) 3 were formed at the three interface regions regardless of the laser power. A larger number of cracks appeared at the interface as the laser power increased to 4200 W. TEM analysis revealed that characterization and thickness of the IMC layer at the interface on the top and bottom were quite distinct. The maximum tensile strength (140.7 MPa) with reinforcement was significantly higher than that of the 6 mm Al/steel fusion welding joints using laser or laser-arc keyhole welding technology. [Display omitted] • Deep-penetration welding-brazing is employed for the joining of 6-mm Al/steel butt plates. • Double IMC layers consist of Fe 2 (Al, Si) 5 and Fe(Al, Si) 3 are formed at the three interface regions. • The characterization of the IMC layer on the top and bottom are enormously distinct. • The maximum tensile strength is higher than that of 6 mm Al/steel fusion welding joints. [ABSTRACT FROM AUTHOR]

• An optimization method that is more in line with the actual situation for CLHS system. • The exergy as objective function is better than energy and entransy. • The recommended boundary conditions are given for CLHS system. • The latent heat capacity has a significant effect on the optimization results. The flow of heat to and from Phase Change Materials (PCMs) is governed by the temperature differences. One of the most viable passive strategy to enhance temperature differences is by using cascaded PCMs. Based on a dynamic heat transfer model coupled with a genetic algorithm, a method for optimizing the performance of cascaded latent heat storage systems is proposed. In this method, the optimization variables and thermal performance based on different objective functions and boundary conditions are investigated. The results show that the mass of the PCM and the number of transfer units (NTU) in each cascaded stage should not always be the same under different objective functions and boundary conditions, unlike in the literature. Additionally, the objective function based on charged exergy is better than that based on charged energy or entransy. Increasing the charging time would increase the charged energy, exergy and entransy, but it will result in a decrease in the efficiencies. As the heat transfer fluid (HTF) has a flow rate greater than 0.2 kg/s, the energy, exergy and entransy efficiencies drop sharply, but have no significant influence on the charged energy, exergy and entransy. For a steady state HTF, an increase of inlet temperature, causes the charged energy, exergy and entransy to increase linearly. However, in this case the rate of temperature increase of the PCMs increase as expected, but the efficiencies decrease slightly. For an unsteady HTF, as the fluctuation in the temperature increases, the charged energy, exergy, entransy along with the efficiencies decrease linearly. In addition, the latent heat capacity of PCMs in different stages will have a significant influence on the optimization variables and thermal performance. In the model in this study, the recommended charging time and HTF flow rate are 3000 s and 0.2 kg/s, respectively. [ABSTRACT FROM AUTHOR]

Red wine grape color and quality decrease substantially at the late stages of ripening in warm climates because of anthocyanin degradation; however, the underlying mechanism remains unclear. We analyzed the anthocyanin metabolite and transcriptome profiles of Yan73 grape berries from two vintages using HPLC-ESI-MS/MS and RNA-sequencing technologies. The results showed that anthocyanins in Yan73 grape skin and flesh were significantly degraded at the late stages of ripening in both vintages. Moreover, non-methylated anthocyanins were degraded at a higher rate than the methylated anthocyanins. The protocatechuic acid (i.e., possible anthocyanin degradation product) concentration increased significantly in Yan73 skin and flesh at the late stages of ripening. However, the expression of anthocyanin biosynthesis-related structural genes and MYBA1 was upregulated in Yan73 skin and flesh at the late stages of ripening, indicating an increase in the anthocyanin synthesis capacity. Enzyme activity and qRT-PCR assays revealed that peroxidase and polyphenol oxidase activities and the VvPrx31 expression level increased in Yan73 skin and flesh at the late stages of ripening, suggesting they may function in the anthocyanin degradation. The β-glucosidase activity was higher only in Yan73 grape flesh at the late stages of ripening. These findings clarify the pre-harvest anthocyanin degradation in grape berries. [Display omitted] • Anthocyanins in Yan73 grape were markedly degraded at late ripening stage in 2 years. • Non-methylated anthocyanins were degraded at a higher rate than the methylated ones. • Anthocyanin synthesis genes were highly expressed in Yan73 grape at late ripening stage. • Peroxidase, polyphenol oxidase activities increased in Yan73 grape at late ripening stage. • One peroxidase gene, Prx31, was highly expressed in Yan73 grape at late ripening stage. [ABSTRACT FROM AUTHOR]

Aiming at the technical difficulty of poor teeth accuracy of the extruded sun gears, an innovative precision finishing approach was developed as the subsequent process of producing high-quality sun gears, and three finishing tools were designed, namely mandrel with gap, mandrel without gap and interference mandrel. A finite element prediction method was proposed by using the post-processing toolbox of DEFORM software to study the distribution laws of outer and inner teeth deviations of the reshaped sun gear. Moreover, the effects of various precision finishing tools on the formability of sun gear (such as tooth deformation, tool stress and tooth accuracy) were investigated. The results show that the tooth accuracy class of the reshaped outer teeth in profile and helix were seventh and eighth, respectively, and the total M-value error of the inner teeth was decreased to 72.3 μm and the reduction ratio was 73.8% by adopting the interference mandrel, which indicates that the finishing effect of the interference mandrel was better than that of mandrels for both with gap and without gap, and the forming accuracy of the finished teeth could be considerably improved. Therefore, the interference mandrel can be recommended as the optimum finishing tool in the manufacture of precision sun gears. The simulated results were in good agreement with experimental ones within a maximum error of 14.4%, which proves the practicability of the sizing approach and the dependability of the finite element prediction method. [ABSTRACT FROM AUTHOR]

An optical fiber current sensor based on helical long-period fiber grating (HLPG) inscribed in polarization-maintaining fiber (PMF) by CO 2 laser has been proposed. The PMF-HLPG is put into the solenoids with a direct current (DC) current source, and the value of applied current can be measured by monitoring the rotation angle of the input elliptical polarized light due to the changes of the magnetic field along the grating. The main factors that affect the rotation angle have been investigated experimentally. The experimental results show a good linear relationship between the rotation angle and the applied current, which indicate that the PMF-HLPG can be used as all fiber current sensor. The maximum sensitivity of the current measurement can be achieved by adjusting the parameters of the input elliptical polarized light. The current sensor based on the PMF-HLPG exhibits high sensitivity even for the detection of small electric current. • The PMF-HLPGs show a large optical activity. • The length of the PMF-HLPG is short. • The fabrication of PMF-HLPG is simpler than that of other optical fibers for current sensing. • The current sensitivity can be changed by adjusting related parameters. [ABSTRACT FROM AUTHOR]

Different from common coaxial couplers used for superconducting radio frequency (SRF) accelerators, power couplers with capacitive coupling in which the inner conductor is separated into two unconnected parts on both sides of the cold ceramic window transmit RF power by capacitive coupling. Capacitive coupling type power couplers have the advantages of easy fabrication of ceramic window, reduced thermal conduction from room temperature side to the cryogenic system, and convenient assembling to cryomodule. To further investigate the performance of this type of RF power couplers, an upgraded power coupler with capacitive coupling has been designed and fabricated at Peking University. The high-power test demonstrated that RF power up to 15 kW in continuous wave (CW) mode can be transmitted steadily. In this paper, the structure, simulation, and high-power test results of this power coupler are presented in detail. [ABSTRACT FROM AUTHOR]

Autophagy serves a crucial role in the etiology of kidney diseases, including drug-induced renal impairment, inherited kidney disease, diabetic nephropathy and aristolochic acid nephropathy (AAN) and is, therefore, a potential target for treatment. We previously demonstrated that rapamycin could attenuate AAN in mice; however, the underlying mechanism remains to be elucidated. Therefore, whether the renal protective effect of rapamycin (an autophagy activator) is related to autophagy in aristolochic acid (AA)-treated mice was of particular interest. The pathophysiological roles of rapamycin were investigated in AA-induced nephrotoxicity in mice and the mechanisms of rapamycin action were explored by evaluating the modulation of autophagy in rapamycin-treated mice and cultured renal tubular epithelial cells. Supplementation with rapamycin reversed AA-induced kidney injury in mice and improved AA-induced autophagy damage in vivo and in vitro. Mechanistically, rapamycin inhibited the renal expression of phosphorylated (p-)mammalian target of rapamycin (mTOR) and p-ribosomal S6 protein kinase 1, which in turn activated renal autophagy and decreased apoptosis, probably by removing AA-elicited damaged mitochondria and misfolded proteins. The findings of the present study demonstrated that rapamycin protects against AA-induced nephropathy by activating the mTOR-autophagy axis and suggested that rapamycin may be a promising pharmacological target for the treatment of AAN. [ABSTRACT FROM AUTHOR]

With excellent biocompatibility, a narrow bandgap, and long thermal carrier lifetime, tin‐based perovskite solar cells (TPSCs) are promising within the solar technology. The fullerene derivative indene‐C60 bisadduct (ICBA) is recognized as the most efficient electron‐transport material for TPSCs, thanks to its suitable band structure. Nevertheless, the limited electron transport capability and susceptibility to moisture penetration of ICBA have hindered the progress of TPSCs. Herein, the study proposes a new hydrophobic electron‐transport layer (ETL) comprising a surface‐anchored non‐fullerene n‐type semiconducting polymer layer, poly (naphthalene diimide‐alt‐dithiophenebezothiadiazole) (PNDI‐BT), in conjunction with ICBA. PNDI‐BT exhibits high electron mobilities, a fitting band structure, robust interaction with Sn‐based perovskites, and exceptional moisture resistance, effectively addressing the shortcomings of ICBA. Consequently, this innovative hydrophobic ETL of PNDI‐BT/ICBA enhances electron transport and protects Sn‐based perovskites from moisture. As a result, the inverted TPSCs with the new hydrophobic ETL achieve an impressive efficiency of 13.90%, surpassing TPSCs with the ICBA layer (12.75%). Moreover, even after 1000 h of storage in ambient atmosphere, the encapsulated TPSC maintains a remarkable 81% of its initial efficiency. This comprehensive study seamlessly integrates the synthesis of non‐fullerene n‐type semiconducting polymer and device fabrication, providing valuable insights into designing cutting‐edge ETL structure for inverted TPSCs. [ABSTRACT FROM AUTHOR]

As an economical energy recovery device, pump as turbine (PAT) is widely used in micro-hydropower stations and the chemical industry. The inlet and outlet pipelines connected to the double-suction pump are on the same horizontal line. As the pipeline layout is very convenient, in some chemical industries, the way of residual pressure energy utilization is increasing using the double-suction pump as a turbine. Based on numerical simulation, experimental verification, and entropy generation theory, the energy loss rule of each flow component in the pump mode and turbine mode under different flow rates is compared and analyzed. The results show that when the double-suction pump is used as a turbine, the flow rate at the best efficiency point (BEP) in the turbine mode shifts to a large flow rate by 30.89% and the BEP efficiency decreases by 1.30%. In the pump mode and turbine mode, the main energy loss component is the impeller, and the turbulent entropy generation power and the wall entropy generation power are the main sources of energy loss. The energy loss in the suction chamber and impeller increases sharply, and the energy loss is primarily enhanced in the blade trailing edge and the tongue near due to the unsteady flow in the turbine mode. Due to the complex structure, the spiral suction chamber is not suitable for the flow direction of the fluid flow out of the impeller, and the flow state inside the impeller is negatively affected by the suction chamber in the turbine mode. This paper provides a theoretical basis for the design and application of double-suction centrifugal PAT. [ABSTRACT FROM AUTHOR]

Endophytic symbioses between plants and fungi are a dominant feature of many terrestrial ecosystems, yet little is known about the signaling that defines these symbiotic associations. Hydrogen peroxide (H2O2) is recognized as a key signal mediating the plant adaptive response to both biotic and abiotic stresses. However, the role of H2O2 in plant–fungal symbiosis remains elusive. Using a combination of physiological analysis, plant and fungal deletion mutants, and comparative transcriptomics, we reported that various environmental conditions differentially affect the interaction between Arabidopsis and the root endophyte Phomopsis liquidambaris , and link this process to alterations in H2O2 levels and H2O2 fluxes across root tips. We found that enhanced H2O2 efflux leading to a moderate increase in H2O2 levels at the plant–fungal interface is required for maintaining plant–fungal symbiosis. Disturbance of plant H2O2 homeostasis compromises the symbiotic ability of plant roots. Moreover, the fungus-regulated H2O2 dynamics modulate the rhizosphere microbiome by selectively enriching for the phylum Cyanobacteria, with strong antioxidant defenses. Our results demonstrated that the regulation of H2O2 dynamics at the plant–fungal interface affects the symbiotic outcome in response to external conditions and highlight the importance of the root endophyte in reshaping the rhizosphere microbiota. [ABSTRACT FROM AUTHOR]

Heterocycle‐linked phthalocyanine‐based COFs with close‐packed π–π conjugated structures are a kind of material with intrinsic electrical conductivity, and they are considered to be candidates for photoelectrical devices. Previous studies have revealed their applications for energy storage, gas sensors, and field‐effect transistors. However, their potential application in photodetector is still not fully studied. The main difficulty is preparing high‐quality films. In our study, we found that our newly designed benzimidazole‐linked Cu (II)‐phthalocyanine‐based COFs (BICuPc‐COFs) film can hardly formed with a regular aerobic oxidation method. Therefore, we developed a transfer dehydrogenation method with N‐benzylideneaniline (BA) as a mild reagent. With this in hand, we successfully prepared a family of high crystalline BICuPc‐COFs powders and films. Furthermore, both of these new BICuPc‐COFs films showed high electrical conductivity (0.022–0.218 S/m), higher than most of the reported COFs materials. Due to the broad absorption and high conductivity of BICuPc‐COFs, synaptic devices with small source‐drain voltage (VDS=1 V) were fabricated with response light from visible to near‐infrared. Based on these findings, we expect this study will provide a new perspective for the application of conducting heterocycle‐linked COFs in synaptic devices. [ABSTRACT FROM AUTHOR]

Heterocycle‐linked phthalocyanine‐based COFs with close‐packed π–π conjugated structures are a kind of material with intrinsic electrical conductivity, and they are considered to be candidates for photoelectrical devices. Previous studies have revealed their applications for energy storage, gas sensors, and field‐effect transistors. However, their potential application in photodetector is still not fully studied. The main difficulty is preparing high‐quality films. In our study, we found that our newly designed benzimidazole‐linked Cu (II)‐phthalocyanine‐based COFs (BICuPc‐COFs) film can hardly formed with a regular aerobic oxidation method. Therefore, we developed a transfer dehydrogenation method with N‐benzylideneaniline (BA) as a mild reagent. With this in hand, we successfully prepared a family of high crystalline BICuPc‐COFs powders and films. Furthermore, both of these new BICuPc‐COFs films showed high electrical conductivity (0.022–0.218 S/m), higher than most of the reported COFs materials. Due to the broad absorption and high conductivity of BICuPc‐COFs, synaptic devices with small source‐drain voltage (VDS=1 V) were fabricated with response light from visible to near‐infrared. Based on these findings, we expect this study will provide a new perspective for the application of conducting heterocycle‐linked COFs in synaptic devices. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskites exhibit superior optoelectrical properties and have been widely used in photodetectors. Perovskite photodetectors with excellent detectivity have great potential for developing artificial photonic synapses which can merge data transmission and storage. They are highly desired for next generation neuromorphic computing. The recent progress of perovskite photodetectors and their application in artificial photonic synapses are summarized in this review. Firstly, the key performance parameters of photodetectors are briefly introduced. Secondly, the recent research progress of photodetectors including photoconductors, photodiodes, and phototransistors is summarized. Finally, the applications of perovskite photodetectors in artificial photonic synapses in recent years are highlighted. All these demonstrate the great potential of perovskite photonic synapses for the development of artificial intelligence. [ABSTRACT FROM AUTHOR]

The lack of ambipolar polymers with balanced hole (μh) and electron mobilities (μe) >10 cm2 V−1 s−1 is the main bottleneck for developing organic integrated circuits. Herein, we show the design and synthesis of a π‐extended selenium‐containing acceptor‐dimeric unit, namely benzo[c][1,2,5]selenadiazol‐4‐yl)ethane (BBSeE), to address this dilemma. In comparison to its sulfur‐counterpart, BBSeE demonstrates enlarged co‐planarity, selective noncovalent interactions, polarized Se−N bond, and higher electron affinity. The successful stannylation of BBSeE offers a great opportunity to access acceptor‐acceptor copolymer pN‐BBSeE, which shows a narrower band gap, lower‐lying lowest unoccupied molecular orbital level (−4.05 eV), and a higher degree of backbone planarity. Consequently, the pN‐BBSeE‐based organic transistors display an ideally balanced ambipolar transporting property with μh and μe of 10.65 and 10.72 cm2 V−1 s−1, respectively. To the best of our knowledge, the simultaneous μh/μe values >10.0 cm2 V−1 s−1 are the best performances ever reported for ambipolar polymers. In addition, pN‐BBSeE shows an excellent shelf‐storage stability, retaining over 85 % of the initial mobility values after two months storage. Our study demonstrates the π‐extended acceptor‐dimeric BBSeE is a promising acceptor building block for constructing high‐performance ambipolar polymers applied in next‐generation organic integrated circuit. [ABSTRACT FROM AUTHOR]

The lack of ambipolar polymers with balanced hole (μh) and electron mobilities (μe) >10 cm2 V−1 s−1 is the main bottleneck for developing organic integrated circuits. Herein, we show the design and synthesis of a π‐extended selenium‐containing acceptor‐dimeric unit, namely benzo[c][1,2,5]selenadiazol‐4‐yl)ethane (BBSeE), to address this dilemma. In comparison to its sulfur‐counterpart, BBSeE demonstrates enlarged co‐planarity, selective noncovalent interactions, polarized Se−N bond, and higher electron affinity. The successful stannylation of BBSeE offers a great opportunity to access acceptor‐acceptor copolymer pN‐BBSeE, which shows a narrower band gap, lower‐lying lowest unoccupied molecular orbital level (−4.05 eV), and a higher degree of backbone planarity. Consequently, the pN‐BBSeE‐based organic transistors display an ideally balanced ambipolar transporting property with μh and μe of 10.65 and 10.72 cm2 V−1 s−1, respectively. To the best of our knowledge, the simultaneous μh/μe values >10.0 cm2 V−1 s−1 are the best performances ever reported for ambipolar polymers. In addition, pN‐BBSeE shows an excellent shelf‐storage stability, retaining over 85 % of the initial mobility values after two months storage. Our study demonstrates the π‐extended acceptor‐dimeric BBSeE is a promising acceptor building block for constructing high‐performance ambipolar polymers applied in next‐generation organic integrated circuit. [ABSTRACT FROM AUTHOR]

Edge structures, thiophene adsorption and hydrodesulfurization (HDS) mechanisms are investigated on the S-edge of triangular MoS2 nanoclusters using density functional theory. The calculated formation energies for different S coverages on the S-edge suggest that the formation of coordinative unsaturated site at the vertex and edge-I (close to the vertex) sites is preferred over the edge-II (away from the vertex) sites. The adsorption of thiophene on the top site of Mo atom mainly occurs at the edge-I, whereas bridge adsorption occurs at the edge-II. The 92% and 50% S-edge coverages involve relatively larger adsorption energies (− 0.68 and − 0.79 eV) among all the possible adsorption configurations. On the S edge with 92% S coverage, the hydrogenation route is more favorable, producing 1-butene. On the S edge with 50% S coverage, the direct desulfurization route is preferred, yielding butadiene. These findings deepen the understanding of edge structures of MoS2 nanoclusters and the corresponding HDS mechanisms for MoS2-based HDS catalysts. [ABSTRACT FROM AUTHOR]

In this paper, WO 3 with specific exposed facets was prepared through hydrothermal method, then Pt nanoparticles were decorated on the surface of WO 3 to enhance the H 2 dissociation ability, and the obtained Pt/WO 3 materials could realize the visualized H 2 detection by the rapid color change of powder. In specific, the high exposure of oxygen ion at c-axis and the shortened diameter of (001) crystal facets is helpful for achieving fast coloring-blenching process. As a result, WO 3 nanowires could exhibit a reflectance change of 86.2%, rapid coloring time (64 s) and recovery rate compared with nanorods and microspheres. Moreover, the detailed influencing mechanism of morphology on diffusion and injection of H and O atoms during gasochromism was revealed. This study could contribute to deepen the understanding of morphology-dependent hydrogen gasochromic performance from microscopic view. • Pt decorated WO 3 hydrogen gasochromic materials with different morphologies were prepared. • The morphology discrepancy of WO 3 resulted in differentiated gasochromic performance. • Enhancing the exposure of O2− at c axis could improve gasochormic performance of WO 3. • The mechanism of morphology-dependent hydrogen gasochromic performance was explored. [ABSTRACT FROM AUTHOR]

Reticular chemistry has been a cornerstone in the design of novel 2D materials. Despite numerous possibilities for topological arrangements, only a few with high symmetry can form stable networks. Here, starting from 2D carbons, four types of highly stable tessellations are discovered, which consist of chains of non‐hexagonal rings separated by hexagonal ribbons. A modified Read–Shockley model is established to perfectly describe the stability of these highly stable frameworks, which is based on the interaction between non‐hexagonal rings. Moreover, these four types of tessellations and the modified Read–Shockley model are found to be of general validity in designing highly stable 2D materials, which is verified by the calculations on polymorphs of boron nitride and molybdenum disulfide. Besides, among the studied 2D carbon allotropes, two semi‐metallic structures with highly anisotropic Dirac cones and one semimetal with a Dirac nodal line at the Fermi level are discovered, as protected by their D2h symmetry. Spin‐orbital coupling is further found to open small bandgaps for these three Dirac structures, making them nontrivial topological insulators. The in‐depth understanding of the stability of 2D crystals in this study provides a new way for rational design of 2D crystals that may show peculiar electronic structures. [ABSTRACT FROM AUTHOR]

We demonstrate an optically tunable mode-locked fiber laser using long-period fiber grating (LPFG) coated with multi-walled carbon nanotubes (CNTs). The multi-walled CNTs can absorb light to convert it into thermal energy, and the resonance wavelength of the grating can be easily turned by varying the external modulated light power. This multi-walled CNT coated LPFG-based all-optical fast and efficient spectrum tunable filter enables continuous tuning of the central wavelength of the laser by manipulating the loss of the mode-locked laser, ensuring the stability of the mode-locking state. In the absence of modulated light on multi-walled CNTs, the soliton laser could generate 890 fs pulses at 1546.7 nm with a spectrum bandwidth of 3.26 nm and a signal-to-noise ratio of 73.1 dB. Through adjustment of the pump power of the modulation light on multi-walled CNTs, the mode-locked fiber laser can be continuously tuned from 1546.71 to 1563.15 nm. The response time of the optically tunable system was measured to be in the order of hundreds of milliseconds. The presented optical tuning filter shows great potential in the fiber laser system, offering a repeatable, straightforward, and rapidly responsive laser tuning technique. [ABSTRACT FROM AUTHOR]

Intrinsically stretchable light‐emitting polymer semiconductors are essential building blocks for bioelectronics and display textiles. Stretchability is challenging for rigid conjugated polymers unless sacrificing charge mobility by introducing amorphous domains. High‐performance light‐emitting properties designed with twisted angle are undesirable for conductive materials. Hence, the concurrent strategies hardly satisfy the balance of stretchability, light‐emitting and mobility. Herein, a morphology engineering is proposed by controlling micro‐crystalline and limiting aggregation, that four intrinsically stretchable emissive polymers with good charge mobility based on indacenodithiophene (IDT) are obtained. Polymers reveal good emission properties with high photoluminescence quantum yields (PLQY) of about 20%, while stretchable modulus and charge mobility are tunable by backbone and weight. Specifically emphasizing, IDT‐2T‐H retains high performance of charge mobility and PLQY even at 100% strain. Therefore, organic light emitting diodes are fabricated based on it and showing the luminance of 176.2 cd cm−2, which verifies the potential of technique to reconcile integration of stretchability, light‐emitting, and mobility. This is the first attempt to integrate balanced mechanical, optical, and electrical properties through micro‐crystalline aggregation‐limited morphology in one polymer, offering a feasible approach to advanced integrated circuit and multi‐functional electronics in the future. [ABSTRACT FROM AUTHOR]

Recently, conductive metal–organic frameworks (c‐MOFs) have drawn tremendous attention for the application in oxygen evolution reaction (OER) due to their superior conductivity and highly accessible active sites. Herein, a facile method is reported to prepare a series of bimetallic c‐MOFs (NixFe1‐x‐THQ, THQ = tetrahydroxy‐1,4‐benzoquinone hydrate) by using the smallest benzene‐based ligand with high‐density catalytic active sites for OER. By adjusting the ratio of Ni/Fe, a series of catalysts with optimal electronic structures and adsorption capacity to intermediates, and faster charge transport are obtained. Among them, Ni0.5Fe0.5‐THQ exhibits superior catalytic performances for OER with a low overpotential of 272 mV at 10 mA cm−2, a small Tafel slope of 47.9 mV, and robust operation for 40 h with no detectable activity decay, which is far superior to commercial RuO2, most of traditional MOFs and even some monometallic conductive MOFs. Moreover, both the measured and simulated results manifest that Ni0.5Fe0.5‐THQ can tailor the d‐band center, and induce the directional transfer of electrons, optimizing the rate‐determining step and adsorption capacity to intermediates during OER, thus exhibits superior electrochemical activity. This work not only presents a strategy to fabricate an electrocatalyst with remarkable OER performance but also promotes the development of THQ‐based c‐MOFs for electrocatalysis. [ABSTRACT FROM AUTHOR]

Apart from the polarization and spatial mode, the degree of coherence (DoC), as a new degree of freedom (DoF), has actuated the control of structured optical fields beyond into a higher dimension. However, the control of DoC mainly focuses on the spatial coherence, and so far, there are no reports on the modulation of temporal coherence of the structured light. Here, a temporal coherence-tailorable vector fiber source is proposed and experimentally demonstrated. With a two-mode long-period fiber grating and polarization control, switchable transverse-mode outputs including azimuthally polarized mode TE01 and radially polarized mode TM01 are performed in an all-fiber compact regime. Benefitting from a tunable superfluorescent fiber source as the illumination of spatial mode control, the temporal coherence and the operating wavelength of vector beams can be simultaneously modulated. This work may not only advance a considerable protocol for creating and manipulating high-dimensional vectorial optical field, but also open up a promising avenue for potential applications in optical communication, high-resolution imaging, and particle trapping. [ABSTRACT FROM AUTHOR]

Constructing uniform covalent organic framework (COF) film on substrates for electronic devices is highly desirable. Here, a simple and mild strategy is developed to prepare them by polymerization on a solid‐liquid interface. The universality of the method is confirmed by the successful preparation of five COF films with different microstructures. These films have large lateral size, controllable thickness, and high crystalline quality. And COF patterns can also be directly achieved on substrates via hydrophilic and hydrophobic interface engineering, which is in favor of preparing device array. For application studies, the PyTTA‐TPA (PyTTA: 4,4′,4′′,4′′′‐(1,3,6,8‐Tetrakis(4‐aminophenyl)pyrene and TPA: terephthalaldehyde) COF film has a high photoresponsivity of 59.79 μA W−1 at 420 nm for photoelectrochemical (PEC) detection. When employed as an active material for optoelectronic synaptic devices for the first attempt, it shows excellent light‐stimulated synaptic plasticity properties such as short‐term plasticity (STP), long‐term plasticity (LTP), and the conversion of STP to LTP, which can be used to simulate biological synaptic functions. [ABSTRACT FROM AUTHOR]

Constructing uniform covalent organic framework (COF) film on substrates for electronic devices is highly desirable. Here, a simple and mild strategy is developed to prepare them by polymerization on a solid‐liquid interface. The universality of the method is confirmed by the successful preparation of five COF films with different microstructures. These films have large lateral size, controllable thickness, and high crystalline quality. And COF patterns can also be directly achieved on substrates via hydrophilic and hydrophobic interface engineering, which is in favor of preparing device array. For application studies, the PyTTA‐TPA (PyTTA: 4,4′,4′′,4′′′‐(1,3,6,8‐Tetrakis(4‐aminophenyl)pyrene and TPA: terephthalaldehyde) COF film has a high photoresponsivity of 59.79 μA W−1 at 420 nm for photoelectrochemical (PEC) detection. When employed as an active material for optoelectronic synaptic devices for the first attempt, it shows excellent light‐stimulated synaptic plasticity properties such as short‐term plasticity (STP), long‐term plasticity (LTP), and the conversion of STP to LTP, which can be used to simulate biological synaptic functions. [ABSTRACT FROM AUTHOR]

Due to the complex structure of a double-suction pump's suction chamber, the flow in the pump's cavity is often ignored in numerical simulations because of difficulties in structured hexahedral meshing. However, the wear ring clearance interlinking the pump chamber leads the fluid at the impeller inlet directly to the impeller area. This significantly impacts the pump's internal flow field, so the influence of the clearance on the internal flow of a double-suction pump cannot be ignored. This paper develops four three-dimensional double-suction pump models with different wear ring clearances to investigate their influence on pump performance, and structured hexahedral meshes were used for all the computational domains. The clearances varied from 0.2 to 0.5 mm in 0.1 mm increments. The influences of the clearance on the energy loss, external characteristics, and internal flow field distribution of the pump were simulated via a verified computational fluid dynamics method. The results show that the wear ring leakage decreases with the flow rate and increases with wear ring clearance. The increase in backflow leads to an internal flow disorder inside the impeller, resulting in a decreased head and efficiency. Energy loss is mainly caused by increasing the turbulence entropy production with an increasing wear ring clearance. Also, the low-pressure region in the pump cavity expands to the volute with increasing clearance, and the impeller outlet pressure decreases. This study's research on wear ring clearance provides a reference for the design and application of double-suction centrifugal pumps. [ABSTRACT FROM AUTHOR]

The progress of neural synaptic devices is experiencing an era of explosive growth. Given that the traditional storage system has yet to overcome the von Neumann bottleneck, it is critical to develop hardware with bioinspired information processing functions and lower power consumption. Transistors based on 2D materials, metal oxides, and organic materials have been adopted to mimic the synapse of a human brain, due to their high plasticity, parallel computing, integrated storage, and system information processing. Among these materials used to build transistors, organic semiconductors are considered to be the most promising candidate for neural synaptic devices and bio‐electronics, owing to their easy processing, mechanical flexibility, low cost, good bio‐compatibility, and ductility. This review focuses on the recent advances in organic synaptic devices with various structures, materials, and working mechanisms. The applications of artificial neural networks that integrate multiple organic synaptic transistors are also concretely discussed. Finally, the challenges that organic synaptic devices currently face are discussed and future developments are forecast. [ABSTRACT FROM AUTHOR]

A N, S co‐doped carbon with abundant vacancy defects (NSC) anchored Pt single atoms (SAs) and nanoclusters (NCs) derived from coal pitch by a self‐assembly‐pyrolysis strategy is reported and a defect‐induced electron redistribution effect based on Pt SAs‐Pt NCs/NSC catalyst is proposed for electrocatalytic hydrogen evolution reaction (HER). The optimized catalyst featuring Pt‐N3S1 SAs and Pt NCs dual active sites exhibit excellent HER activity with an overpotential of 192 mV at a current density of 400 mA cm−2, a turnover frequency of 30.1 s−1 at an overpotential of 150 mV, which the mass activity is 13716 mA mgPt−1, 7.4 times higher than that of 20% Pt/C catalyst. In situ Raman revealsa direct correlation between the defect structure of the catalyst and hydrogen adsorption during the reaction process. Density functional theory calculation shows the defect‐induced electron redistribution between Pt‐N3S1 SAs and Pt NCs. The electrons are transferred from Pt NCs to Pt SAs, which increases the number of electrons on the surface of Pt SAs and enhances the adsorption ability of H+. Meanwhile, the dissociation ability of H* on the Pt NCs is promoted, thus synergistically promoting the HER process. [ABSTRACT FROM AUTHOR]

Y‐series non‐fullerene acceptors (NFAs) have achieved great progress in organic solar cells (OSCs). Most research attention is currently paid to their molecular engineering to improve the efficiency of OSCs. However, as n‐type organic semiconductors, the relationship between their molecular packing structures and charge transport properties is mostly ignored. Herein, it is clarified how the molecular packing of Y‐series NFAs fundamentally determines their charge transport properties by manipulating their crystal stacking via sidechain engineering. Therefore, branched alkyl/alkoxy substitutions are taken on a reference NFA (Y6‐1O), affording three derivatives, namely 1OBO‐1, 1OBO‐2, and 1OBO‐3. Results show that while the replacement of branched alkyl/alkoxy sidechains has little impact on optical properties and energy levels, it can change crystal stacking motifs significantly. The single crystal of Y6‐1O with all linear sidechains forms a 2D‐brickwork structure and shows lower mobility. In contrast, 1OBO‐2 with all branched sidechains exhibits a favorable 3D interpenetrating porous network, displaying an electron mobility of 1.42 cm2 V−1 s−1 in single‐crystal organic field‐effect transistors (SC‐OFETs). This value is among the highest for NFA‐based n‐type OFETs. This study not only reveals the fundamental structure–property relationships of Y‐series NFAs, but also suggests the potential of Y‐series NFAs for high‐performance n‐type organic semiconductors. [ABSTRACT FROM AUTHOR]

Lubricating oil is easily polluted by solid particles, causing it to deteriorate; therefore, solid particles must be separated from the oil. Furthermore, as conventional filtration devices cannot meet both filtration accuracy and service life requirements, an oil and solid separation method for multi-gradient filtration enhanced by an electric field is proposed. A numerical model for multi-gradient separation was established by coupling the governing equations of electric and flow fields, the particle-wall collision equation, and the discrete phase-tracking equation. Enhanced by an electric field, the characteristics of the multi-gradient filtration of solid particles in oil were investigated using finite element method. The effects of the main control parameters on the filtration performance were analyzed. The results indicate that using the electric field-enhanced multi-gradient filtration method can achieve highly efficient separation of solid particles from the oil. When the electric field strength was increased from 0 kV/mm to 2 kV/mm, the deposition concentration of particles was 2.5 times higher and filtration efficiency of the system increased to 97.46%. Additionally, the deposition concentration and filtration efficiency decreased from 0.15 m/s to 0.3 m/s, while gradually increased from 0.3 m/s to 0.5 m/s, for a particle size range of 10–40 µm. [Display omitted] • An oil and solid separation method for multi-gradient filtration enhanced by an electric field was proposed. • A numerical model for multi-gradient separation enhanced by an electric field was established. • Characteristics of electric field-enhanced multi-gradient of solid particles in oil were investigated. • The effects of the main control parameters on the filter efficiency were analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly dispersed Pd-Mn 3 O 4 catalyst was constructed by limited pyrolysis oxidation strategy. • Strong metal-support interaction effect between Pd and Mn 3 O 4 make the surface electron rich. • Strong metal-support interaction effect was conducive to catalyse propane degradation. Adjusting the interaction between dual active components for enhancing volatile organic compounds (VOCs) degradation is an effective but still challenging means of air pollution control. Herein, a limited pyrolysis oxidation strategy was adopted to prepare Pd-Mn 3 O 4 spinel catalysts with uniform morphology and active component dispersion. Among these, 1.08Pd-Mn 3 O 4 presented the highest catalytic efficiency with a T 90 value of 240 °C, which was 94 °C lower than that of Mn 3 O 4. Characterization and density functional theory (DFT) calculation results revealed that the strong metal-support interaction (SMSI) effect between Pd and Mn 3 O 4 promoted the redistribution of surface charges, thus strengthening the oxidation-reduction ability of the active sites. Moreover, the SMSI effect led to a better migration of surface oxygen species, and boosted the generation of active surface oxygen species. Simultaneously, the Pd catalyst further reduced the energy barrier in the initial stage of the dehydrogenation of propane. Overall, this study provided a novel design strategy for dual active components catalysts with SMSI effect and extended the application of these catalysts in the important field of VOCs elimination. [ABSTRACT FROM AUTHOR]

Carbon nanorings (CNRs) and carbon nanobelts (CNBs) of various sizes and innovative molecular architectures have ushered improvement in research in recent years. This serves as a prerequisite for further advances and applications, such as organic semiconductors and bottom‐up synthesis of single‐walled carbon nanotubes. Nevertheless, challenges such as high strain energy, excessive reactivity, end‐product stability, low‐scale yields, and side reactions inhibit material synthesis and applications. In this review, CNRs, CNBs, and other heteroatom‐doped molecular belts are discussed based on their molecular structural characteristics, with a special focus on their developments in the past two years. Furthermore, current applications, research obstacles, and future developments related to CNRs and CNBs are discussed. For the first time, studies and advancements in organic field‐effect transistors (OFETs) have been summarized in detail. [ABSTRACT FROM AUTHOR]

The microbially induced carbonate precipitation (MICP) technique has been used to increase mechanical strength, reduce permeability, and fix radionuclides of soils, etc. To achieve effective soil cementation by MICP, 3 aspects should be considered: MICP efficiency, bacterium retention (in soils after injections), and precipitation uniformity. Here, experiments and statistical analyses were conducted to understand the parameters affecting the 3 aspects. Moreover, the parameters leading to better performance in these aspects were designed and used to conduct MICP soil cementation with varying the number of injections. The results present that temperature and OD600nm of bacterial suspension are the most important parameters affecting MICP efficiency, followed by reaction time, pH, and concentration of cementation solution, and they are all statistically significant. As these parameters increased, MICP efficiency (ratio of CaCO 3 formed to Ca2+ added) first increased quickly and then slowly or decreased. The soil particle size distribution and injection rate affected bacterium retention greatly. Smaller particle sizes, wider particle-size-distribution spans, and slower injection rates are beneficial to bacterium retention. However, higher injection rates favour precipitation uniformity. Finally, the unconfined compressive strength (UCS) of the bio-treated soil can be increased further by increasing the number of injections. • Evaluates the factors influencing MICP efficiency. • Analyzes the effect of particle size distribution and injection rate on bacterium retention. • Studies the uniformity of precipitation at different injection rates. • Examines the cementation strength of the soil at different grouting times under preferred parameter. [ABSTRACT FROM AUTHOR]