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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]

As a basic and crucial security requirement for Wireless Sensor Networks (WSNs), authentication is generally used to prevent various communication attacks such as Denial-of-Service (DoS) attack. A novel broadcast authentication framework is proposed in this paper, where an Identity-Based Signature scheme by using the Extended Chaotic Maps (ECM-IBS) is designed to authenticate all broadcast messages and specifically, a chaos-based hash function is used for message authentication in the WSNs. It is implemented using a WSN hardware device of CC2530 and its performance is analyzed under various methods. Performance analysis and experimental results show that the proposed ECM-IBS scheme has a quick signature generation speed, low energy consumption and short verification delay, and can be applied to WSN applications. [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]

Described herein is the merging of allylic C(sp3)–H activation and directed C(sp2)–H activation into a single approach for discovering unprecedented chemical transformations. As a proof-of-concept, we disclose for the first time the rhodium-catalyzed regioselective oxidative annulation of anilines with allylbenzenes to deliver a variety of indoles. In this work, the C3 and C2 positions of the allylic segment are set to construct C–N and C–C bonds, respectively. [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]

Bimetallic Ni-Cu/SAPO-11 catalysts were prepared by co-impregnation method and assessed in the hydroisomerization of n -octane. Their physicochemical properties were characterized by means of powder X-ray diffraction, nitrogen adsorption-desorption, temperature-programmed desorption of ammonia, pyridine-adsorbed infrared spectroscopy, temperature-programmed reduction of hydrogen, transmission electron microscopy, energy dispersive X-ray, and X-ray photoelectron spectroscopy. The Ni-Cu alloy was formed after reduction in the H 2 flow at 450 °C. Copper changed the electronic interaction of nickel and diluted the nickel ensemble size in the Ni-Cu alloy. The hydrogenolysis reaction that decreases the selectivity of isomerization was effectively restrained over the bimetallic Ni-Cu/SAPO-11 catalysts. The selectivity to n -octane isomers over the bimetallic nickel (3%) and copper (1.5%) catalyst was 19% more than that over the monometallic nickel (3%) catalyst at the conversion of 70%. A possible reaction scheme was proposed to explain the catalytic properties in n -octane hydroisomerization. [ABSTRACT FROM AUTHOR]

In this work, we utilize the quasinormal modes (QNMs) of a massless scalar perturbation to probe the Van der Waals-like small and large black holes (SBH/LBH) phase transition of charged topological Anti-de Sitter (AdS) black holes in four-dimensional massive gravity. We find that the signature of this SBH/LBH phase transition is detected in the isobaric as well as in the isothermal process. This further supports the idea that the QNMs can be an efficient tool to investigate the thermodynamical phase transition. [ABSTRACT FROM AUTHOR]

The left circumflex coronary artery associated with a fistula to superior vena cava is a rare entity. We describe a 7-year-old girl who presented with a cardiac murmur and was diagnosed with a coronary artery fistula between the left circumflex artery and superior vena cava by echocardiography. The surgical occlusion of the fistula was successful. [ABSTRACT FROM AUTHOR]

The chaotic map has complex dynamics under ideal conditions however it suffers from the problem of performance degradation in the case of finite computing precision. In order to prevent the dynamics degradation, in this paper the continuous Chen chaotic system is used to perturb both the inputs and parameters of Chebyshev map to minimize the chaotic degradation phenomenon under finite precision. Experimental evaluations and corresponding performance analysis demonstrate that the Chebyshev chaotic map has a good randomness and complex dynamic performance by using the proposed perturbation method, and some attributes of the proposed system are stronger than the original system (e.g. chaos attractor and approximate entropy). Finally, the corresponding pseudorandom number generator (PRNG) is constructed by this method and then its randomness is evaluated via NIST SP800-22 and TestU01 test suites, respectively. Statistical test results show that the proposed PRNG has high reliability of randomness, thus it can be used for cryptography and other potential applications. [ABSTRACT FROM AUTHOR]

A novel dehydrodimerization of malonates with indoles has been developed, providing simple and rapid access to 3-indolyl tetramethyl 1,1,2,2-ethanetetracarboxylates. Pd(OAc) 2 -catalyzed ‘one pot’ C(sp 2 )–C(sp 3 ) and C(sp 3 )–C(sp 3 ) cross-dehydrogenative-couplings of malonates with a variety of 2-aryl indoles were involved. The titled compounds were obtained in high yields with good functional group tolerance. [ABSTRACT FROM AUTHOR]

Amorphous structure discovered from both the wear debris and the friction layer of the carbon/carbon composites after the braking tests was attributed to the breakdown of crystallites in the graphitized bulk material. Graphite layers produced through interlayer shear deformation were found to be the basic units of the pyrocarbon during sliding while carbon fiber tended to be worn into small fragments along the fiber axis in the primary stage of rubbing. The transition of graphitic pyrocarbon in the friction process was described as four stages. Nano-scale carbon particles of onion-like structure were found in the fiction layer, which were likely to participate in the formation of friction layer and lubricate the friction process. [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]

Colalt sulfide nanocrystals (NCs), including dandelion-like Co 9 S 8 and sphere-like Co 3 S 4 , have been synthesized via a thermal decomposition approach using cobalt acetylacetonate as the cobalt source, 1-dodecanethiol as the sulfur source and oleic acid or oleylamine as the high boiling organic solvent. It is found that the molar ratio of the Co:S precursor and the species of solvent play an important role in the control of phase and morphology of cobalt sulfide nanostructures. The phase structure and morphology of the as-synthesized nickel sulfide NCs are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), energy dispersive spectrum (EDS) mapping, X-ray photoelectron spectroscopy (XPS) and N 2 adsorption–desorption. Then we further compare the electrocatalytic activity and stability of as-synthesized cobalt sulfide NCs for hydrogen evolution reaction (HER). The results show that sphere-like Co 3 S 4 exhibits better electrocatalytic activity than the dandelion-like Co 9 S 8 NCs for HER, which can be attributed to the difference of phase structure and morphology. The sphere-like Co 3 S 4 NCs have large surface area and high electrical conductivity, both are beneficial to enhance the catalytic activity. This study indicates that the crystalline phase structure and morphology of cobalt sulfide NCs are important for designing HER electrocatalysts with high efficiency and good stability. [ABSTRACT FROM AUTHOR]

In this paper, an efficient method to fabricate Al-based metal organic framework (Al-MOF) MIL-96 crystals with controllable size and morphology, by mixing other forms of reactants to replace the coordination modulators or capping agents, is presented. The size and morphology of the MIL-96 crystals can be selectively varied by simply altering the ratio of dual reactants via their hydrolysis reaction. All the samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA) and nitrogen sorption. Then based on the BFDH theory, a mechanism for the impact of hydrolysis of reactants on the crystal size and morphology is presented and discussed. We also evaluated the performance of these MOFs as sorbents for capturing CO2, and they all show enhanced adsorption properties compared with the bulk material, displaying high adsorption capacities on CO2 at atmospheric pressure and ambient temperature. [ABSTRACT FROM AUTHOR]

New electrocatalysts to replace noble metal catalysts for the hydrogen evolution reaction (HER) are highly desired to produce renewable and environmentally-friendly energy. In this work, nanostructured nickel phosphides supported on carbon nanospheres (CNSs) with different carbon content (Ni 2 P/CNSs- x , x = 10, 20, 40, 60) are synthesized by thermal decomposition using nickel acetylacetonate as nickel source and trioctylphosphine as phosphorus source in an oleylamine solution containing CNSs for the first time. The structure and morphology are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), and N 2 adsorption-desorption. Then the electrocatalytic properties of as-synthesized Ni 2 P/CNSs- x for the HER are studied. In addition, the Ni/CNSs-20 hybrid is synthesized and the electrocatalytic properties are studied. The results show that all the Ni 2 P/CNSs hybrids exhibit higher catalytic activity than the Ni/CNSs-20 hybrid. The catalytic activity of the as-synthesized Ni 2 P/CNSs hybrid can be enhanced by changing the carbon content. The superior catalytic activity is attributed to the coupling effect between the Ni 2 P nanoparticles and CNSs, the electronic effect of Ni, the ensemble effect of P, the large surface area, and the high electron conductivity of CNSs. This study paves the way for the design of HER electrocatalysts with high performance and low-cost that can be employed under acid conditions. [ABSTRACT FROM AUTHOR]

NiMo catalysts were prepared using Waugh-type NiMo heteropolycompounds as active phase precursors and evaluated in hydrodesulfurization (HDS) of dibenzothiophene (DBT). These catalysts were compared with corresponding reference catalysts prepared from the conventional precursors (ammonium heptamolybdate and nickel nitrate). Prepared catalysts were characterized by N physisorption, XRD, FT-IR, H-TPR, DRIFT of CO adsorption and HRTEM techniques. It was found that NiMo catalysts prepared from Waugh-type NiMo HPCs showed higher performance in HDS of DBT than their counterparts. Possible reasons of this result were discussed. Graphical Abstract: [Figure not available: see fulltext.] [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]

Poly-4-hydroxybutyrate, P(4HB), is a biosynthetic thermoplastic polymer that has been studied as a bio-absorbable medical material. In order to explore the in vivo biodegradation behaviour of porous P(4HB) membranes with specified apertures (89–150 µm), membranes with different porosities were implanted subcutaneously into the backs of 27 eight-week-old Sprague Dawley® rats. The implanted specimens were examined with Masson and hematoxylin and eosin staining. Masson staining indicated that the P(4HB) membranes were encased in fibrous cysts and that more collagen fibers were present within the sections of the hyper-porosity group. Hematoxylin and eosin staining showed that the residual area of the P(4HB) membranes in the hyper-porosity group decreased sharply compared to the hypo-porosity group, which implied that the P(4HB) membranes with higher porosity degraded faster than those with lower porosity. A slow degradation phase persisted for approximately 14 weeks during the degradation process. After the 16th week, the P(4HB) scaffolds fell into a fast degradation phase. The residual areas of the hyper-porosity P(4HB) membranes at the 32nd week were reduced by 39.76% compared with the second week after implantation. We concluded that P(4HB) membranes manifest a special biodegradation behavior in vivo and that the increased porosity of these membranes is an important factor favoring their biodegradation rates. [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]

Abstract: A bifunctional NiPb/ZnO-diatomite-ZSM-5 (NiPb/ZnO-DZSM-5) catalyst for FCC gasoline upgrading by reactive adsorption desulfurization (RADS) coupling olefin aromatization function was prepared by wet-mixed squeezed method to avoid octane number loss from olefins hydro-saturation in traditional RADS processing. The crystalline structure and textural property of as-prepared adsorbents/catalysts were characterized by X-ray powder diffraction (XRD) and N2 adsorption analysis, respectively. Adsorption desulfurization and aromatization activities evaluation of FCC gasoline and model gasoline over different adsorbents/catalysts were investigated. The results showed directly introducing the composite of aromatization catalyst into the reactive adsorption desulfurization adsorbent is difficult to conquer the loss of gasoline octane number from olefin saturation and sustain the ultra deep desulfurization ability of the reactive adsorption desulfurization process simultaneously. However, the prepared Pb-modified Ni/ZnO-DZSM-5 catalysts (by introducing second metal into Ni/ZnO-DZSM-5 catalyst), exhibited improved aromatization and desulfurization performance with low octane number loss. The aromatic concentration in products increased with the additive amount of ZSM-5 in catalyst composition, meanwhile, as the adding Pb cannot destroy the original crystalline phase, Pb-modified NiPb/ZnO-ZSM-5 catalyst can inhibit olefin saturation effectively with high desulfurization activity. Regenerated bifunctional NiPb/ZnO-DZSM-5 catalyst also exhibits excellent desulfurization and aromatization performance with no octane number loss. [Copyright &y& Elsevier]

Abstract: Mesoporous boehmite with different morphologies have been prepared by a surfactant-free solvothermal technique with an alcohol-toluene mixed system, and the corresponding γ-Al2O3 was obtained after sequential calcination. The effects of the type of alcohol on the crystalline structure, textural properties, morphology, and acidity of the products were investigated through a series of characterizations, including XRD, SEM, TEM, nitrogen physisorption, 27Al MAS NMR, and Py-IR. The results indicate that alcohol molecules with different number of carbon atoms make a strong impact on the growth of boehmite crystallites and their sequent assemblies. Longer alkyl chain in the alcohol molecule is favorable for the formation of boehmite with hierarchical structures. The changes in crystalline structure further affect the pore structure and surface acidity of the alumina samples. Besides, different inorganic salts including Ca(NO3)2·4H2O, Cu(NO3)2·3H2O, Co(NO3)2·6H2O, MgCl2·6H2O, Zn(NO3)2·6H2O, and Fe(NO3)3·9H2O were used instead of Al(NO3)3·9H2O to synthesize the corresponding hydroxides, and the results show that other hydroxide hierarchical structures with similar morphologies can be also obtained through this simple solvothermal route. [Copyright &y& Elsevier]

Abstract: In this paper, systematical investigation has been made for the new simple synthesis pathway of catalytic alumina with high surface area through thermal decomposition of ammonium aluminum carbonate hydroxide (AACH), which has been prepared by a low-temperature solid-state reaction in non-aqueous system. The results indicate that the molar ratios of NH4HCO3/Al influence crystallinities and the morphologies of AACH. Well-crystallized AACH with nanorod morphology and low-crystallized AACH with cluster structure can be obtained with different molar ratios NH4HCO3/Al. The γ-Al2O3 product with high surface area (511m2/g) can be obtained from the calcination of AACH at 500°C. Moreover, the results also indicate that crystallinities and morphologies of AACH affect their thermal decomposition behaviors. In addition, the formation of high-surface-area is possibly attributed to intracrystalline porosity of as-prepared γ-Al2O3. [Copyright &y& Elsevier]

Abstract: Hierarchically organized γ-AlOOH hollow spheres with nanoflake-like porous surface texture have been successfully synthesized via an ionic liquid-assisted hydrothermal synthesis method in citric acid monohydrate (CAMs). It was found that ionic liquid [bmim]+Cl− played an important role in the morphology of the product due to its strong interactions with reaction particles. The samples were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM). The results show that the product has narrow particle size distribution (500–900nm particle diameter range), high specific surface area (240.5m2/g) and large pore volume (0.61cm3/g). The corresponding γ-Al2O3 hollow spheres can be obtained by calcining it at 550°C for 3h. The proposed formation mechanism and other influencing factors of the γ-AlOOH hollow sphere material, such as reaction temperature, reaction duration, CAMs and urea, have also been investigated. [Copyright &y& Elsevier]

Abstract: A series of aluminas were obtained through rehydration–dehydration of the initial alumina under different hydrothermal conditions. To investigate the influences of rehydration temperature on the physicochemical properties of the as-obtained aluminas, several techniques were applied, such as X-ray powder diffraction, nitrogen adsorption, scanning/transmission electron microscopy, Fourier transform infrared, thermogravimetric analysis, and 27Al MAS NMR. The results show that crystal size and morphology of alumina particles changed as the treatment temperature was increased, and alumina crystallites grew mainly along two surface orientations. Consequently, the changes in textural properties of the aluminas took place. In addition, the rehydration process increased not only the weak acid sites but also the strong acid sites, which is closely related to the growth of the (111) and (110) surfaces of γ-Al2O3. The two type acid sites were originated from coordinately unsaturated four-fold aluminum atoms. TPR for a series of Ni(Mo) catalysts were carried out and the results show that rehydration process increased the surface acidity and basicity of alumina simultaneously, which enhanced the interacting force of Ni and Mo species with aluminas respectively. This interaction is closely related to the hydrodenitrogenation (HDN) activity of quinoline over the corresponding NiMo/γ-Al2O3 catalysts. [Copyright &y& Elsevier]

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]

Abstract: We develop a holographic superconductor in BTZ black hole background with backreactions. We investigate the influence of the backreaction on the condensation of the scalar hair and the dynamics of perturbation in the background spacetime. When the Breitenlohner–Freedman bound is approached, we argue that only one of two possible operators can reflect the real property of the condensation in the holographic superconductor. This argument is supported by the investigation in dynamics. [Copyright &y& Elsevier]

Abstract: We investigate the perturbations of charged scalar field in 5-dimensional Gauss–Bonnet AdS black hole backgrounds. From the perturbation behaviors we obtain the objective picture on how the high curvature influences the spacetime perturbation and the condensation of the scalar hair. The high curvature effects can also be read from the linear response function such as the susceptibility and the correlation length, when the system approaches the critical point. We find that the Gauss–Bonnet term does not affect the critical exponents of the system and they still take the mean-field values. [Copyright &y& Elsevier]

Abstract: Boehmite (AlOOH) with hierarchical flower-like structures was synthesized by the solvothermal reaction of AlCl3·6H2O in the presence of ethanol and toluene at 200°C for 24h. The product was characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that boehmite with flower-like nanostructures, which aggregated together by the weak hydrogen bonds, was formed through dissolution–deposition process of boehmite microcrystals and the toluene has a great effect on the morphology of product in the reaction system. Meanwhile, the γ-Al2O3 was also obtained by calcination of above product at 500°C for 2h, and the flower-like morphology kept no change. The surface area of γ-Al2O3 powder was determined to be 166.8m2/g by N2 adsorption measurement. The possible formation mechanism of flower-like boehmite nanostructures was proposed and discussed. [ABSTRACT FROM AUTHOR]

Organic thin-film transistors based on polycrystalline copper phthalocyanine (CuPc) were fabricated by using poly(vinyl alcohol) as gate dielectric. After treatment of the gate dielectric using an octadecyltrichlorosilane self-assembled monolayer, a mobility of up to 0.11 cm2/V s was achieved, which is comparable to that of single-crystal CuPc devices (0.1–1 cm2/V s). The surface morphology was analyzed and the possible reasons for the enhanced mobility are discussed. [ABSTRACT FROM AUTHOR]

To realize graphene-based electronics, various types of graphene are required; thus, modulation of its electrical properties is of great importance. Theoretic studies show that intentional doping is a promising route for this goal, and the doped graphene might promise fascinating properties and widespread applications. However, there is no experimental example and electrical testing of the substitutionally doped graphene up to date. Here, we synthesize the N-doped graphene by a chemical vapor deposition (CVD) method. We find that most of them are few-layer graphene, although single-layer graphene can be occasionally detected. As doping accompanies with the recombination of carbon atoms into graphene in the CVD process, N atoms can be substitutionally doped into the graphene lattice, which is hard to realize by other synthetic methods. Electrical measurements show that the N-doped graphene exhibits an n-type behavior, indicating substitutional doping can effectively modulate the electrical properties of graphene. Our finding provides a new experimental instance of graphene and would promote the research and applications of graphene. [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]

Abstract: The pyrolysis of iron(II) phthalocyanine on an Au substrate under an atmosphere of ethanol/argon was found to produce recumbent bamboo-like multi-walled carbon nanotubes. By changing the pattern of the Au bars in the substrate, the configuration of the nanotube could be changed. A possible mechanism for the formation of these patterns is suggested. [Copyright &y& Elsevier]