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The bonding properties of BFRP composites have been demonstrated in previous studies, satisfying the strength and durability criteria. In this paper, a further in-depth study is carried out to bond Basalt Fibre Reinforced Polymer (BFRP) to Aluminum Alloy 5052 using two bonding agents, Aralite® 2012 and Aralite® 2015, respectively. The salt sprays under 80 °C, 3.5% NaCl environment; 80 °C, 5% NaCl environment; and pure water environment are also considered for comparison. Experimental results show that joints created with Araldite® 2012 adhesives show higher average breaking strength (10.66 MPa at 720 h) and better ductility in a 5% NaCl environment. While the Araldite® 2015 adhesive joint exhibits a combination of tear failure and interface failure, along with thin-layer cohesion failure. In the SEM images of the two adhesive joints' failure, fiber pullout due to tension and damage at the interface between fiber and resin is apparent. To validate the experimental outcomes, water absorption testing, DSC, TGA-DTG, and FTIR experiments were conducted on dog-bone-shaped adhesive specimens to elucidate the results. [ABSTRACT FROM AUTHOR]

Isopropanol has been widely applied in various fields as an important chemical solvent, which is produced by direct hydration of propylene accompanied with the byproduct of n‐propanol. Herein, an ultra‐sensitive fluorescent probe of TPA‐9AC, based on a non‐equivalent hybridized local and charge‐transfer (HLCT) material, is designed and synthesized to quantitatively detect the percentage of n‐propanol in propanol isomers. Owing to the stronger electron acceptor ability of n‐propanol, the excited state of probe transfers from highly emissive HLCT state to non‐emissive charge‐transfer state, resulting in the substantial fluorescence quenching. The low limit of detection (LOD) is achieved as sensitive as 0.02% v/v of n‐propanol in isopropanol. This contribution demonstrates a new approach to distinguish propanol isomers and an effective strategy for designing real‐time fluorescent sensors with high performances. [ABSTRACT FROM AUTHOR]

Mechanoresponsive luminescent (MRL) materials have become a high-profile research system in the fields of force sensing, anti-counterfeiting, and optical information storage because of their obvious variety on luminescence intensity or luminescence color under mechanical force. In this work, nitro-triphenylamine (TPA-NO2) crystal was selected to conduct in situ high pressure experiments based on diamond anvil cell combined with theory calculation, and the piezochromism of TPA-NO2 crystal was discussed in detail. During the compression process, the TPA-NO2 crystal showed the piezochromic behavior and a redshift of the emission peak. The mechanical response behavior of TPA-NO2 provides insight into the study of multicolor properties from a structural perspective, offering a clean means of using pressure to modulate different colors and contributing to the exploration of high-potency MRL materials. [ABSTRACT FROM AUTHOR]

In this study, we synthesized eight water-soluble ionic liquids (ILs) and investigated their tribological performance as additives in water-diethylene glycol (WDG) base fluids. The results of the tribological test suggested that these ILs additives demonstrate promising capabilities in friction reduction and anti-wear for water lubricated contacts. The ILs with the longest carboxylic chain length, namely C 10 MIPA and C 10 DIPA in this work, displayed superior tribological performances. Observations on the abraded surfaces showed that the IL forms a monolayer adsorption through self-assembly, and upon rubbing it creates a continuous and stable tribo-film with an uneven thickness of 30–60 nm through tribo-chemical reactions. The tribo-film mainly consists of iron oxides. The proposed lubrication mechanisms include adsorbed film and formed tribo-films, which work effectively to reduce the shear stress and thus sliding friction. [ABSTRACT FROM AUTHOR]

To improve room‐temperature phosphorescence (RTP) property, thianthrene (TA) is chemically modified into three intramolecular dimers (1TA1TA, 1TA2TA, and 2TA2TA) at different active sites. They all show dual‐emission of fluorescence and RTP after deoxygenation when they are dispersed in polymer matrix to form films. As for the RTP emission among their films, 2TA2TA shows the largest red shift peaking at 540 nm, the longest lifetime of 36.5 ms, and the highest RTP efficiency of 40.7%. These RTP characteristics enable 2TA2TA to act as a self‐referenced ratiometric and colorimetric probe for oxygen sensing and detection at low concentration. As a result, 2TA2TA exhibits the highest quenching efficiency of 98.4% and highest sensitivity (KSV = 13.32 KPa−1) for quantitative oxygen detection. Besides, these oxygen‐sensitive materials can also be used to study aerodynamics through a direct and visual observation of emission intensity/color distribution. Overall, the new‐generation optical probe will be developed in oxygen sensing and detection with high sensitivity, good reversibility, and reproducibility by using the pure organic materials with single‐molecule dual‐emission of fluorescence and RTP through the dispersion of the materials in polymeric host. [ABSTRACT FROM AUTHOR]

Organic materials with excitation wavelength‐dependent (Ex‐de) emission are highly attractive for anticounterfeiting, optoelectronics and bioassay applications; however, the realization of Ex‐de fluorescence, independent of aggregation states, remains a challenge. We herein report a photoinduced electron transfer (PeT) strategy to design Ex‐de fluorescence materials by manipulating the relaxation pathways of multiple excited states. As expected, the o‐carborane dyad presents a clear Ex‐de fluorescence colour in the aggregated states, resulting from the tunable relative intensity of the dual‐fluorescence spectra. Taking TP[1]B as an example, the amorphous powders emitted bright blue‐violet, white and yellow colours under 390 nm, 365 nm and 254 nm UV illumination, respectively. Importantly, multicolour, flexible and transparent films as well as an anticounterfeiting application using this o‐carborane dyad are demonstrated. [ABSTRACT FROM AUTHOR]

Organic materials with excitation wavelength‐dependent (Ex‐de) emission are highly attractive for anticounterfeiting, optoelectronics and bioassay applications; however, the realization of Ex‐de fluorescence, independent of aggregation states, remains a challenge. We herein report a photoinduced electron transfer (PeT) strategy to design Ex‐de fluorescence materials by manipulating the relaxation pathways of multiple excited states. As expected, the o‐carborane dyad presents a clear Ex‐de fluorescence colour in the aggregated states, resulting from the tunable relative intensity of the dual‐fluorescence spectra. Taking TP[1]B as an example, the amorphous powders emitted bright blue‐violet, white and yellow colours under 390 nm, 365 nm and 254 nm UV illumination, respectively. Importantly, multicolour, flexible and transparent films as well as an anticounterfeiting application using this o‐carborane dyad are demonstrated. [ABSTRACT FROM AUTHOR]

Millimeter-wave massive multiple-input multiple-output is a key technology in 5G communication system. In particular, the hybrid precoding method has the advantages of being power efficient and less expensive than the full-digital precoding method, so it has attracted more and more attention. The effectiveness of this method in simple systems has been well verified, but its performance is still unknown due to many problems in real communication such as interference from other users and base stations, and users are constantly on the move. In this article, we propose a dynamic user clustering hybrid precoding method in the high-dimensional millimeter-wave multiple-input multiple-output system, which uses low-dimensional manifolds to avoid complicated calculations when there are many antennas. We model each user set as a novel Convolutional Restricted Boltzmann Machine manifold, and the problem is transformed into cluster-oriented multi-manifold learning. The novel Convolutional Restricted Boltzmann Machine manifold learning seeks to learn embedded low-dimensional manifolds through manifold learning in the face of user mobility in clusters. Through proper user clustering, the hybrid precoding is investigated for the sum-rate maximization problem by manifold quasi-conjugate gradient methods. This algorithm avoids the traditional method of processing high-dimensional channel parameters, achieves a high signal-to-noise ratio, and reduces computational complexity. The simulation result table shows that this method can get almost the best summation rate and higher spectral efficiency compared with the traditional method. [ABSTRACT FROM AUTHOR]

The new energy vehicle system is in the initial stage of application, so the probability of fault is greater. Therefore, its reliability urgently needs to be improved. In order to improve the fault diagnosis effect of new energy vehicles, this paper proposes a fault diagnosis system of new energy vehicle electric drive system based on improved machine learning and also proposes several typical fault detection and diagnosis methods. Through the study of the operating characteristics and structural characteristics of the electric drive system and the analysis of the fault mechanism, this paper classifies the main faults of the electric drive system according to the self-test requirements of the electric drive system and the online diagnosis requirements and presents the self-test fault tree and online diagnosis fault tree of the electric drive system. In addition, this paper designs experiments to verify the performance of the system proposed by this paper, simulates the current common system fault conditions, and uses the system constructed in this paper to perform system fault diagnosis. The research results show that the performance of the fault diagnosis system for drive energy vehicles constructed in this paper is reliable. [ABSTRACT FROM AUTHOR]

With the continuous spread of COVID-19 epidemic, the strict control of personnel makes it a problem to optimize the design of vehicle parameters after field measurement. The energy absorption characteristics and deformation mode of the front structure of the vehicle determine the acceleration or force response of the vehicle body during the impact, which plays an important role in occupant protection. The traditional multi-objective optimization method is to transform multi-objective problems into single objective optimization problems through weighted combination, objective planning, efficiency coefficient and other methods. This method requires a strong prior knowledge. The purpose of this paper is to combine the experimental design with the Multi-objective Particle Swarm Optimization (MPSO) method to achieve the optimization of the crash worthiness of automobile structure. This method can effectively overcome the defect of low precision caused by the conventional response surface method in the whole design space. In this paper, the multi-objective particle swarm optimization method is applied to the research of Crash worthiness optimization of automobile structure, which expands the application field of the multi-objective particle swarm optimization method, and also has a very big role in the optimization of other complex systems. It can be seen from the experiment that the speed of multi-objective particle swarm optimization is much faster than that of other methods. Only 100 iterations can get the relative better results. The case study on the front structure of a car shows that the method has a good result. It is of great significance to apply the method to the optimization design of the crash worthiness of the car structure to improve the crash safety of the car under the influence of COVID-19 epidemic. [ABSTRACT FROM AUTHOR]

Developing the single‐molecule white‐light emitters (SMWLEs) at room temperature is very challenging for pure organic metal‐free system, and it is even more challenging to achieve the high efficiency of pure organic SMWLE. Here, alkoxy substituents are tailored at 2‐positioned thioxanthone (TX) to finely tune the molecular packing mode and the intermolecular interaction between TX units, and the photoluminescence (PL) efficiency (ΦPL) of SMWLE is improved successfully from 1.5% (TX) to 45.0% (TX‐OCH(CH3)2). This simultaneous enhancement of dual emission between fluorescence and phosphorescence can be ascribed to i) a moderate intersystem crossing (ISC) rate for the equilibrium distribution between singlet and triplet excitons, ii) simultaneously accelerated radiative rates of singlet and triplet excitons due to J‐aggregation of TX units, and iii) effective suppression of nonradiation through strong hydrogen bond interactions by alkoxy chains. As a result, this work provides a novel molecular design strategy to harvest high‐efficiency pure organic SMWLE using a precise manipulation of π–π stacking mode and intermolecular interaction by tailoring alkoxy substituents. [ABSTRACT FROM AUTHOR]

Optimized Al:ZnO sputtering target was prepared by cold isostatic pressing (CIP) using nanostructured zinc oxide powder and aluminum oxide powder as raw material. Compared with the target prepared by conventional raw materials, the performance of the optimized Al:ZnO sputtering target is greatly improved. The microstructure of the optimized Al:ZnO sputtering target is refined and its average grain size is less than 5 μm with 99.7% theoretical density. Al:ZnO thin films of both optimized and conventional targets were prepared by RF magnetron sputter and their properties were characterized, respectively. The Al:ZnO thin films obtained by optimized target feature better uniformity and compactness, and the internal stress is −378.8 MPa, which is nearly 2/3 lower than that of the conventional target. The film obtained by optimized targets also features a 97% IR transmittance, 1.71 nm Rq surface roughness and non-offset (002) XRD peak. It can be speculated that the optimized Al:ZnO target has great potential to prepare micrometer scale Al:ZnO films and employed in thin-film ZnO device industry. [ABSTRACT FROM AUTHOR]

Integrating evaporative cooling with loop thermosyphon can significantly improve the free cooling ability. In this paper, a loop thermosyphon with evaporative condenser is investigated experimentally. The mist water flow out of a single nozzle is observed and analyzed. The performance and annual free cooling potential of the system are investigated, compared with conventional loop thermosyphon. The results show that the evaporative cooling effect of the locations below the horizontal level of the nozzle is more significant due to gravity. With the increase of horizontal distance from the nozzle, the temperature decreases and then increases and the optimal distance is 200–400 mm. The heat capacity of LTEC increases with the increase of indoor and outdoor temperature difference while it decreases with the increase of humidity. Evaporative cooling can enhance the heat transfer of LTEC by 7%–33% compared with loop thermosyphon with conventional condenser, and this value is larger for smaller indoor and outdoor temperature difference and higher indoor temperature. LTEC can expand the annual free cooling time by 7%–14% compared with LTCC and the effect is more significant in regions with drier weather. • Loop thermosyphon with evaporative condenser (LTEC) is studied experimentally. • Temperature field and flow field of the water spray out of a single nozzle are analyzed. • The distance with the best evaporative cooling effect is 200–400 mm from the nozzle. • The heat transfer of LTEC is 7%–33% larger than LTCC. • The annual free cooling time of LTEC is 7%–14% larger than LTCC. [ABSTRACT FROM AUTHOR]

The first total synthesis of speradine C has been achieved in only ten steps from a commercially available 4‐bromoindole. Salient features of the work are the formation of four rings through three cyclizations, namely a bioinspired [3+2] annulation to form the C/D rings, an NCS‐mediated oxidation to construct the E ring, and a Ru‐catalyzed ketohydroxylation to assemble the F ring. This work highlights how strategic ring constructions can streamline the synthesis of polycyclic compounds. [ABSTRACT FROM AUTHOR]

The first total synthesis of speradine C has been achieved in only ten steps from a commercially available 4‐bromoindole. Salient features of the work are the formation of four rings through three cyclizations, namely a bioinspired [3+2] annulation to form the C/D rings, an NCS‐mediated oxidation to construct the E ring, and a Ru‐catalyzed ketohydroxylation to assemble the F ring. This work highlights how strategic ring constructions can streamline the synthesis of polycyclic compounds. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mg-V-O oxides supported on the MgO-coated silica were constructed by co-impregnation of magnesium and vanadium citrates. • The structures of surface V species evolved from monovanadates to Mg 3 V 2 O 8 crystallites with increasing the V contents. • The intrinsic performance of surface V species for the ODH of propane was investigated and correlated to their structures. • Supported Mg 3 V 2 O 8 crystallites with size of 15–30 nm are intrinsically selective towards the ODH of propane to propylene. Abstract Supported Mg-V-O oxides were prepared by co-impregnation of magnesium and vanadium citrates with MgO-coated mesoporous silica (SBA-15). Their structures were characterized by complementary techniques including powder X-ray diffraction, Raman spectroscopy, diffuse reflectance UV–vis spectroscopy and transmission electron microscopy. These catalysts were examined in oxidative dehydrogenation (ODH) of propane to propylene, and the reaction kinetic parameters of k 1 / k 2 and k 3 / k 1 were analyzed, which represent the ratios of the rate constants for primary propane ODH (k 1) to propane combustion (k 2) and that for secondary propylene combustion (k 3) to k 1 , respectively. Characterization results show the structural evolution of the vanadium species from isolated VO 4 monovanadates to Mg 3 V 2 O 8 crystallites, without formation of crystalline V 2 O 5 , with increasing the vanadium content from 1.7 wt% to 25.6 wt%. Dispersed monovanadates exhibited higher propane ODH rates than Mg 3 V 2 O 8 crystallites, in line with their higher reducibility probed by temperature-programed reduction in H 2 , but they were less selective to propylene due to the favorable propylene combustion over its formation, as reflected by the higher k 3 / k 1 ratios. The supported Mg 3 V 2 O 8 crystallites with sizes of about 15–30 nm, relative to those of above 30 nm, were found to be intrinsically more selective for the propane ODH, consistent with their higher k 1 / k 2 and lower k 3 / k 1 ratios. Consequently, they offered the superior selectivities and yields of propylene at higher propane conversions. Such understanding on the intrinsic catalytic properties of the Mg-V-O oxides and particularly Mg 3 V 2 O 8 crystallites provides new insights into the structural requirement for the propane ODH reaction, beneficial to design of more efficient Mg-V-O-based catalysts for the production of propylene. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Intrinsic catalytic performances of MgV 2 O 6 , α-Mg 2 V 2 O 7 , Mg 3 V 2 O 8 and their biphasic mixtures were obtained in the ODH of propane. • α-Mg 2 V 2 O 7 consisting of corner-shared V-O-V units is the most selective Mg-V-O phase for the ODH of propane to propylene. • No synergetic effect exists between either α-Mg 2 V 2 O 7 and Mg 3 V 2 O 8 or Mg 3 V 2 O 8 and MgO in the ODH of propane to propylene. Abstract MgV 2 O 6 , α-Mg 2 V 2 O 7 and Mg 3 V 2 O 8 model catalysts with high phase purity were prepared and studied in the oxidative dehydrogenation (ODH) of propane to determine the active and selective Mg-V-O crystalline structures required for the propane ODH reaction. Initial activities and selectivities, and rate constants for the propane ODH (k 1), propane combustion (k 2) and propylene combustion (k 3) reactions were rigorously measured within the kinetically controlled regime. MgV 2 O 6 exhibited the highest propane turnover rates, but it was not a selective phase for the formation of propylene, due to the favorable propylene combustion on its surface reflected by the high k 3 / k 1 ratio. α-Mg 2 V 2 O 7 exhibited both superior propane ODH rates and propylene selectivity relative to Mg 3 V 2 O 8 , indicating that α-Mg 2 V 2 O 7 consisting of dimeric V 2 O 7 units is intrinsically more active and selective than Mg 3 V 2 O 8 containing isolated VO 4 tetrahedra in the ODH of propane, consistent with the smallest k 2 / k 1 and k 3 / k 1 ratios measured for α-Mg 2 V 2 O 7 among the three pure Mg vanadates. Moreover, a detailed comparison between the crystalline Mg-V-O catalysts and their physical mixtures in terms of the intrinsic activities and selectivities demonstrated no synergetic effects between either α-Mg 2 V 2 O 7 and Mg 3 V 2 O 8 or Mg 3 V 2 O 8 and MgO phases in the ODH of propane. This study provides directions for optimization of compositions and design of new structures based on the well-studied Mg-V-O catalysts towards the efficient synthesis of propylene from the ODH of propane. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Parallel flow field with micro-distributor can increase cell output by over 20%. • Modified flow field needs much lower pressure than the serpentine one. • Micro-distributor can significantly enhance the uniform distribution of flow. • Increasing mean pressure drop in sub-channels can improve flow uniformity. Abstract The flow field on bipolar plates of proton exchange membrane fuel cells (PEMFCs) is critical to flow distribution and overall pressure drop, both of which have great influence on cell performance. A micro-distributor was proposed to improve the uniformity of flow distribution in parallel flow field. The effects of micro-distributor size on output cell performance and pressure drop were systematically studied with computational fluid dynamics (CFD) simulations. To evaluate the competence of the modified parallel flow field, a serpentine flow field was also considered for comparison. The results suggest that the modification of the flow field is able to enhance the uniformity of flow distribution significantly. The maximum output power density increases when decreasing the size of micro-distributor. Compared with the serpentine flow field, the modified parallel flow field with micro-distributor enables the fuel cell to give nearly comparable output performance, but requires two orders of magnitude lower pressure. More generally, it was found that the flow uniformity could be simply and conveniently improved by enhancing the mean pressure drop in the sub-channels. The origin of non-uniform distribution of oxygen concentration in the interface of gas diffusion layer (GDL) and catalyst layer (CL) was also discussed. This work provides an alternative to conventional parallel and serpentine flow fields, and is helpful for the designing of high output PEMFCs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Slope turn in hydrophobic channel can enhance water removal from MEA surface. • Slope turn should has the same sectional area as the straight channel. • Optimized slope angle is dependent on water behavior and pressure drop. • Large wall contact angle can accelerate water transport. Abstract Aim to effectively improve the removal and transport of liquid water in the flow channel in a proton exchange membrane fuel cell (PEMFC), we designed a slope turn in the serpentine flow channel and conducted numerical simulations using volume-of-fluid method to investigate the water behavior in it. To optimize the slope turn, the effects of the sectional area and slope angle of the slope turn and the wettability of channel wall on the transport and dynamics of water were investigated. Besides, cases with different sizes of single water droplet and the interactions between multiple droplets were also considered. For single droplet, the results suggest that with the designed slope turn, water droplet can be effectively removed from the surface of membrane electrode assembly (MEA) though the channel walls are hydrophobic. Without slope turn, the water droplet is transported downstream, always being attached on the MEA surface. The designed slope turn is also applicable for the case of multiple droplets to enhance water removal from the MEA surface. [ABSTRACT FROM AUTHOR]

The tumor starvation microenvironment plays a pivotal role in the malignant progression of cancer, which is closely related to autophagy, glycolysis, and epithelial mesenchymal transition (EMT). Nevertheless, the underlying mechanisms of the starvation-mediated malignant phenotype are still not well documented. In this study, we aimed to investigate the effect of starvation on glycolysis, autophagy, and EMT in OSCC and to further elucidate the key metabolic modulator. The results showed that starvation can induce autophagy, EMT, and enhanced glycolysis in OSCC cells. We determined that the expression of the key glycolytic enzyme phosphofructokinase-platelet (PFKP) obviously increased under starvation conditions and that PFKP knockdown inhibited starvation-mediated glycolysis, autophagy and EMT in OSCC cells. Moreover, we confirmed that PFKP knockdown inhibited OSCC xenograft growth in vivo. In addition, PFKP expression was significantly increased in OSCC patients and its upregulation was associated with the presence of tumor pathological differentiation and lymph node metastasis. Taken together, our findings demonstrate that PFKP is necessary for starvation-mediated autophagy, glycolysis, and EMT, thereby promoting the malignant progression of OSCC. [ABSTRACT FROM AUTHOR]

Abstract: Organic light‐emitting materials are centered on their excited states. However, excited‐state geometry is hardly solved. Herein, the planar distance of an anthracene excimer is determined by integrating a monodisperse dimeric anthracene stacking in crystal and high‐pressure technique. The crystal exhibits the pure excimer fluorescence at ambient conditions, and a unique photophysical phenomenon is observed under pressure: fluorescence peak keeps constant first and then starts a gradual redshift. The theoretical potential energy curve indicates that this starting point of redshift corresponds to the excimer equilibrium geometry, which will be innovative to determine the excited‐state π–π interplanar distance (Re) in experiment. Moreover, high‐pressure synchrotron powder X‐ray diffraction experiment tactfully determines Re = 3.330 Å at the pressure point of initial redshift. This work not only suggests the Re determination by an original pathway but also reports a unique excimer photophysics, which may provide a reference benchmark for the further theoretical and experimental studies on aromatic excimer. [ABSTRACT FROM AUTHOR]

Chinese medicinal herbs (CMH) have been considered a potentially efficacious approach for patients with breast cancer that experience adverse effects from endocrine treatment. To investigate the impact of CMH on endocrine therapy-induced side effects in patients with hormone receptor-positive (HR+) breast cancer. Ten databases (e.g., PubMed, Web of Science, Cochrane Library, China National Knowledge Information Database and other databases) were searched up to 20 May 2022. The search terms included Chinese herb, breast cancer, endocrine therapy, clinical trial and their mesh terms. The study selection and data extraction were performed by two independent reviewers. The risk of bias was evaluated using the Cochrane risk of bias method. A total of 31 studies with 2288 patients were included. There were significant improvements in bone mineral density (BMD) [lumbar BMD (MD 0.08, 95% CI 0.07 to 0.09, p < 0.00001) and femoral neck BMD (MD 0.08, 95% CI 0.07 to 0.10, p < 0.00001)] and bone gal protein (BGP) (MD 0.24, 95% CI 0.17 to 0.31, p < 0.00001), with a significant reduction in triglycerides (MD −0.53, 95% CI −1.00 to −0.07, p < 0.05) and no effect on estradiol levels (MD 0.90, 95% CI −0.31 to 2.12, p = 0.15). CMH combined with complementary therapy can moderately reduce endocrine therapy-induced side effects, including bone loss and dyslipidemia in patients with HR + breast cancer, revealing the potential role of CMH in treating (HR+) breast cancer. More high-quality RCTs are warranted to further validate the effectiveness and safety of CMH. [ABSTRACT FROM AUTHOR]

Covering: 2000 to 2017 Ergot alkaloids are among the most important pharmaceuticals and natural toxins. Significant progress has been achieved in recent years on the research of ergot alkaloids. In this review, we re-introduced the history of ergot alkaloids. Meanwhile, we summarized all the natural products and semi-synthetic derivatives of ergot alkaloids. We also briefly described the biosynthesis and semi-synthesis of ergot alkaloid drugs from raw materials obtained by fermentation. Moreover, we reviewed the advances that have been made in the total synthesis of ergot alkaloids since 2000. [ABSTRACT FROM AUTHOR]

• Short- and long-term impacts of variables were determined using the pooled mean group (PMG) • According to the co-integration test, the research sample was co-integrated. • Urbanization has very little impact on environment, both in short term and over long term. • Immediate as well as long-term effects of human energy use on the ecosystem have been demonstrated. Carbon emissions are well-established as a major contributor to global warming and other climate change effects. This work experimentally explores the influence of energy consumption, economic development, urbanization, and energy consumption on carbon emission utilizing panel cointegration tests and pooled mean group (PMG-ARDL) approaches, drawing on panel data of the Chinese country from 1995 to 2020. We add urbanization to the model to determine its significance in the interplay between GDP growth, energy consumption, and carbon emissions. The results show that urbanization has no appreciable impact on environmental quality either immediately or in the long term. Energy usage, on the other hand, was proven to considerably increase environmental harm both immediately and over time. Further research indicated that environmental distortion is a long-term effect of economic expansion for the countries studied. The key to achieving a green and clean environment is in the hands of government officials and politicians, who must pay close attention to improving appropriate energy, urban planning, and pollution reduction without slowing economic growth. [ABSTRACT FROM AUTHOR]

Molecular conformation is closely related to its luminescence process, and pressure is one of the effective tools to regulate molecular conformation. In this letter, we studied the evolution of salicylic acid crystal fluorescence under high pressure and obtained enhanced emission during the compression. At 0–4 GPa, the rotamerization process led to the energy dissipation, which resulted in the fluorescence quenching. After 4 GPa, the rotamerization process completed. The excited-state intramolecular proton transfer (ESIPT) process of SA was inhibited, and due to the strengthened intermolecular hydrogen bond, the non-radiative decay reduced, which resulted in emission enhancement. This work reveals the impact of hydrogen bond and molecular conformation on luminescence and ideas for the development of new small-molecule luminescent materials are furnished. [Display omitted] • Molecular isomerization can be induced by high pressure. • Pressure can control the excited-state intramolecular proton transfer process. • The pressure-induced emission enhancement can be achieved by restrict chemical bond vibrations. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel diketone-linked polyimide (PTN) is explored as cathode material for LIBs. • PTN has π-conjugated structure and abundant redox-active sites. • PTN cathode exhibits excellent rate performance and long cycle life. Aromatic polyimides have been considered promising organic cathode materials for lithium-ion batteries (LIBs) due to their excellent solvent resistance, superior electrochemical capability and highly designable structure. However, the inferior intrinsic conductivity and limited redox-active sites lead to their suboptimal comprehensive electrochemical performance and restrict their applications in LIBs. Herein, a novel conjugated diketone-based polyimide (PTN) cathode material with multiple carbonyl redox sites is proposed and prepared for LIBs. The integration of electron-withdrawing π-conjugated diketone with naphthimide can effectively regulate the electronic structure and elevate the working potential of the polyimide-based cathode, and improve its comprehensive electrochemical performance. The PTN-based cathode delivers a high specific capacity of 213.4 mAh g−1, excellent cycling stability (97.3% capacity retention after 2000 cycles at 2000 mA g−1) and high rate performance (78.2% capacity retention at 2000 mA g−1 vs. 50 mA g−1), high gravimetric energy density (380 Wh kg−1) at a high power density (4417 W kg−1) simultaneously. This comprehensive electrochemical performance is among the best results of reported polyimide cathode materials and suggests that PTN has great potential in energy storage applications. [ABSTRACT FROM AUTHOR]

Recently, perovskite solar cells (PSCs) have attracted widespread attention due to their outstanding advantages. Hole-transport-material-free carbon-based PSCs (C-PSCs) are some of the most potential devices. However, intrinsically inferior contact at perovskite/carbon interfaces and low conductivity of carbon electrode are restricting the commercial application of C-PSCs. In this study, an N, O co-doped biomass porous composite carbon electrode based on KOH-activated soybean dregs carbon, conductive carbon black and polymethylmethacrylate—N-KSDC—is prepared via a spraying method to efficiently improve perovskite/carbon interface qualities as well as enhance the efficiency and stability of C-PSCs. The results showed that the best power conversion efficiencies of N-KSDC-based C-PSCs with an active area of 0.08 and 1 cm2 were 13.45% and 11.08%, respectively. In addition, unencapsulated PSCs retained 92% of their initial power conversion efficiencies under ambient conditions without intentionally controlling humidity for 62 days. In this study, we propose a feasible and effective strategy to improve the performance and stability of perovskite/carbon interfaces in C-PSCs. [Display omitted] • An N, O co-doped biomass porous composite carbon electrode was prepared. • PMMA was used to improve adhesion and passivate to the perovskite film. • Spraying method effectively improved the interface quality. • The PCE of up to 13.45% (0.08 cm2) and 11.08% (1 cm2) were achieved. • The prepared C-PSCs had excellent long-term stability. [ABSTRACT FROM AUTHOR]

Efficient conversion of cellulose, the most abundant biomass on Earth, to chemicals in high yields remains a formidable challenge. Here, we report the marked change in the distribution of polyol products in the cellulose reaction on Ru/C and WO 3 /C, strongly depending on the competitive reactions of the glucose intermediate. WO 3 crystallites not only promote, as a solid acid, the efficient hydrolysis of cellulose to glucose, but also catalyze the selective cleavage of the C–C bonds in glucose and other C 6 sugar intermediates, leading to the formation of ethylene glycol and propylene glycol, in competition with the sugar hydrogenation to the corresponding C 6 polyols (e.g. sorbitol) on Ru/C. The basic C support, behaving similar to other solid bases (i.e. MgO), catalyzes the isomerization of glucose into fructose, leading to the favored formation of propylene glycol instead of ethylene glycol. Such strong dependence of the product distribution on the catalytic functions is clarified by the kinetic analysis of the three competitive reactions of glucose, including its hydrogenation, isomerization and C–C bond cleavage. Importantly, such kinetic analysis can predict the maximum selectivity ratio of propylene glycol to ethylene glycol, which is 2.5, for example, at 478 K under the reaction conditions in this work, corresponding to a maximum yield of propylene glycol of ∼71%. These understandings shed new insights into the selective conversion of cellulose, which provides guidance for the rational design of catalyst functions and tuning of reaction parameters towards the controllable synthesis of specific products from cellulose. [ABSTRACT FROM AUTHOR]

Herein, we report an anthracene-based material, 2-(anthracen-9-yl)thianthrene (2-TA-AN), whose crystal exhibits excimer fluorescence with an unexpected high luminous efficiency (up to 80%) and long lifetime (163.75 ns), due to pairwise anthracene stacking. These results will update the traditional view that excimers are poorly efficient in photoluminescence. [ABSTRACT FROM AUTHOR]

Piperidine is an important cyclic amine with versatile applications. However, its commercial process is not green and depends mainly on the hydrogenation of fossil resource-based pyridine. Here, we report a novel one-pot approach to the sustainable synthesis of piperidine from bio-renewable tetrahydrofurfurylamine (THFAM) via its hydrogenolysis to 5-amino-1-pentanol (APO) and the subsequent intramolecular amination of APO. SiO2-supported Rh–ReOx catalysts exhibited high efficiency and stability in the THFAM reaction to piperidine, providing a high yield of 91.5% at 200 °C and 2.0 MPa H2 in water. Such high efficiency of Rh–ReOx/SiO2 was found to be related to the synergistic effect between the Rh nanoparticles and ReOx species on the kinetically-relevant cleavage of the C–O bond neighboring the C–NH2 group in THFAM, involving the strong adsorption of the C–NH2 group on ReOx and the heterolytic dissociation of H2 on Rh. This work provides an efficient strategy for the selective cleavage of the C–O bonds neighboring the C–NH2 groups, irrespective of their presence in amino ethers or amino alcohols, and the green production of piperidine and its derivatives from biomass resources. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ni/C with solid bases catalyzes xylitol hydrogenolysis to two target glycols. [•] Bases prevent Ni particles agglomeration and leaching in xylitol hydrogenolysis. [•] The yield to ethylene glycol, propylene glycol and glycerol reaches ∼70% on Ni-CaO/C. [•] Lactic acid formation is negligible on basic oxide-promoted Ni/C catalysts. [Copyright &y& Elsevier]

Highlights: [•] 1,1-Diethoxyethane is efficiently synthesized in a high yield of 35.0% from a single feedstock of ethanol in a two sequential reactors. [•] Cu/SiO2 efficiently catalyzes selective ethanol dehydrogenation to acetaldehyde with a 99.0% selectivity. [•] H-Y zeolite with dominant Brönsted acid sites is efficient for acetalization of acetaldehyde to 1,1-diethoxyethane with ethanol. [ABSTRACT FROM AUTHOR]

[Display omitted] • Macroscopic kinetic models of disaccharides hydrolysis were established. • NbP showed high catalytic performance in hydrolysis of disacchrides. • The reaction order is 1.0 over all the substrates and 0.45–0.82 over the acid site. • Decomposition is more sensitive to temperature change than hydrolysis. • The consecutive reaction of monosaccharides occurred in bulk aqueous solution. Macroscopic kinetic models were established to describe the overall hydrolysis process of disaccharides with different type of glycosidic bond and constituted monosaccharides over hierarchically porous niobium phosphate (NbP) aiming for evaluating reaction efficiency of saccharide hydrolysis over solid acid. The NbP sample was synthesized by a sol–gel method accompanied by phase separation with co-continuous macroporous structure and high P/Nb molar ratio. The synthesized NbP sample showed high catalytic performance in the hydrolysis of disaccharides in an aqueous solution. Sucrose with α (1 → 2) glycosidic bond was the most easily hydrolyzed, with almost 100% conversion and monosaccharide yield, followed by melibiose α (1 → 6) and maltose α (1 → 4), while cellobiose β (1 → 4) was the strongest against to be hydrolyzed. The kinetic analysis showed that the reaction order is 1.0 over all the substrates and varied from 0.45 to 0.82 over the acid site, depending on the type of disaccharide. The activation of the decomposition reaction was larger than that of hydrolysis reaction, indicating that decomposition is more sensitive to temperature change than hydrolysis. Accordingly, direct decomposition of the disaccharides and the constituent monosaccharides synergistically determined the final yield and selectivity of the monosaccharides. Further, the decomposition and dehydration of glucose and galactose were found to occur in the bulk aqueous solution instead of on the surface of NbP. [ABSTRACT FROM AUTHOR]

Excitation‐dependent emission (Ex‐de) materials have been of considerable academic interest and have potential applications in real life. Such multicolour luminescence is a characteristic exception to the ubiquitously accepted Kasha's rule. This phenomenon has been increasingly presented in some studies on different luminescence systems; however, a systematic overview of the mechanisms underlying this phenomenon is currently absent. Herein, we resolve this issue by classifying multicolour luminescence from single chromophores and dual/ternary chromophores, as well as multiple emitting species. The underlying processes are described based on electronic and/or geometrical conditions under which the phenomenon occurs. Before we present it in categories, related photophysical and photochemical foundations are introduced. This systematic overview will provide a clear approach to designing multicolour luminescence materials for special applications. [ABSTRACT FROM AUTHOR]

Excitation‐dependent emission (Ex‐de) materials have been of considerable academic interest and have potential applications in real life. Such multicolour luminescence is a characteristic exception to the ubiquitously accepted Kasha's rule. This phenomenon has been increasingly presented in some studies on different luminescence systems; however, a systematic overview of the mechanisms underlying this phenomenon is currently absent. Herein, we resolve this issue by classifying multicolour luminescence from single chromophores and dual/ternary chromophores, as well as multiple emitting species. The underlying processes are described based on electronic and/or geometrical conditions under which the phenomenon occurs. Before we present it in categories, related photophysical and photochemical foundations are introduced. This systematic overview will provide a clear approach to designing multicolour luminescence materials for special applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] High acetol yields from cellulose, and also from glucose and fructose were obtained. [•] The mechanism of cellulose conversion to acetol on bimetallic Ni-SnO x /Al2O3 catalysts was studied. [•] SnO x facilitated the isomerizaiton of glucose to fructose and its subsequent C C bond cleavage. [•] The hydrogenation activity of the Ni-SnO x /Al2O3 catalysts depends on the Sn/Ni ratio. [ABSTRACT FROM AUTHOR]

Abstract: A full sequence of TaHSP70 (heat shock protein 70 of Tanichthys albonubes) was amplified which was 2398bp, including an open reading frame (ORF) of 1392bp encoding a polypeptide of 643 amino acids with all three HSP70 family signatures and cytosolic motif of EEVD. Genomic DNA structure analysis revealed that the TaHSP70 gene contained one intron in 5′UTR. BLAST analysis revealed that the TaHSP70 gene shared high similarity with other known HSP70 genes. The alignment of inferred amino acid sequences also showed high degrees of similarity among the homologues. There was a basal mRNA expression of TaHSP70 in the different tissues from the non-exposed T. albonubes and the highest expression level in the liver. To investigated the time- and dose-dependent relationship of the expression of TaHSP70 following exposure to heavy metals, T. albonubes were exposed to 2−1 96h-LC50 (0.027mgL−1), 4−1 96h-LC50 (0.0135mgL−1) of copper and 2−1 96h-LC50 (2.31mgL−1), 4−1 96h-LC50 (1.15mgL−1) of cadmium for 96h. Hsp70 expression relative to the control was analyzed by Quantitative real-time PCR and Western blotting. The results indicated that there were a dose-dependent expression pattern and an exposure time effect in the liver responded to heavy metal stress. Interestingly, TaHSP70 gene expressions did not show consistent changes between transcription and translation levels. Taken together, the dynamics of TaHSP70 expression observed provided important insight into heavy metal stress, heat shock protein activity, and the potential ways to monitor the chronic stressors in T. albonubes culture environments. [Copyright &y& Elsevier]

A carbon nanoparticle ionic liquid (CNPIL) as a conductive agent and binder is introduced into an activated carbon electrode to improve supercapacitor performance. It has a high specific capacitance of 223 F g−1, high power density (1.64 kW kg−1 at 83.2 W h kg−1) and high charge–discharge efficiency (97.3%). [ABSTRACT FROM AUTHOR]

Cellulose is the most abundant source of biomass in nature, and its selective conversion into polyols provides a viable route towards the sustainable synthesis of fuels and chemicals. Here, we report the marked change in the distribution of polyols in the cellulose reaction with the Sn/Pt atomic ratios in a wide range of 0.1–3.8 on the SnOx-modified Pt/Al2O3 catalysts. Such a change was found to be closely related to the effects of the Sn/Pt ratios on the activity for the hydrogenation of glucose and other C6 sugar intermediates involved in the cellulose reaction as well as to the notable activity of the segregated SnOx species for the selective degradation of the sugar intermediates on the Pt–SnOx/Al2O3 catalysts. At lower Sn/Pt ratios of 0.1–1.0, there existed electron transfer from the SnOx species to the Pt sites and strong interaction between the catalysts, as characterized by temperature-programmed reduction in H2 and infrared spectroscopy for CO adsorption, which led to their superior hydrogenation activity (per exposed Pt atom), and in-parallel higher selectivity to hexitols (e.g. sorbitol) in the cellulose reaction, as compared to Pt/Al2O3. The hexitol selectivity reached the greatest value of 82.7% at the Sn/Pt ratio of 0.5, nearly two times that of Pt/Al2O3 at similar cellulose conversions (∼20%). As the Sn/Pt ratios exceeded 1.5, the Pt–SnOx/Al2O3 catalysts exhibited inferior hydrogenation activity (per exposed Pt atom), due to the formation of the crystalline Pt–Sn alloy, which led to the preferential conversion of cellulose to C2 and especially C3 products (e.g. acetol) over hexitols, most likely involving the isomerization of glucose to fructose and retro-aldol condensation of these sugars on the segregated SnOx species, apparently in the form of Sn(OH)2. These findings clearly demonstrate the feasibility for rational control of the cellulose conversion into the target polyols (e.g. acetol or propylene glycol), for example, by the design of efficient catalysts based on the catalytic functions of the SnOx species with tunable hydrogenation activity. [ABSTRACT FROM AUTHOR]

Abstract: Background: It has been proved that pre-treatment with leonurine could protect brain tissue against ischemic injury by exerting antioxidant effects and regulating mitochondrial function. Whether this protective effect applies to acute phase after cerebral ischemia, we therefore investigate the potential neuroprotective role of leonurine and the underlying mechanisms in cerebral ischemia. Methods: Focal cerebral ischemia was induced in adult male Sprague-Dawley rats by permanent middle cerebral artery occlusion (MCAO). Leonurine was administered intraperitoneally at 7.5 or 15mg/kg/d at 2h after surgery, then once daily thereafter. Neurological deficit, brain water content, and infarct volume were measured at 24h, 72h, and 7d after stroke. Superoxide dismutase (SOD), catalase (CAT) activities, and malondialdehyde (MDA) content were also measured by spectrophotometer to evaluate oxidative reactions, and the expression of uncoupling protein 4 (UCP4), Bcl-2, and Bax were detected by reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemical staining (IHC), and western blot, while the ultrastructure of the mitochondria were observed under transmission electron microscope. Results: Leonurine significantly alleviated neurological deficit, decreased brain water content and infarct volume after ischemic stroke, which was accompanied by decreased levels of MDA and Bax, increased activities of SOD, CAT, UCP4, and Bcl-2, and restored ultrastructure of mitochondria. Conclusions: The results showed that leonurine protected brain injury by increased activities of UCP4, SOD, CAT and Bcl-2, decreased levels of MDA and Bax, and ameliorated ultrastructure of mitochondria in experimental stroke. [Copyright &y& Elsevier]

The selective hydrogenolysis of biomass-derived xylitol to ethylene glycol and propylene glycol was carried out on different catalysts in the presence of Ca(OH)2. The catalysts included Ru supported on activated carbon (C) and, for comparison, on metal oxides, Al2O3, TiO2, ZrO2and Mg2AlOxas well as C-supported other noble metals, Rh, Pd and Pt, with similar particle sizes (1.6–2.0 nm). The kinetic effects of H2pressures (0–10 MPa), temperatures (433–513 K) and solid bases including Ca(OH)2, Mg(OH)2and CaCO3were examined on Ru/C. Ru/C exhibited superior activities and glycol selectivities than Ru on TiO2, ZrO2, Al2O3and Mg2AlOx, and Pt was found to be the most active metal. Such effects of the metals and supports are attributed apparently to their different dehydrogenation/hydrogenation activities and surface acid-basicities, which consequently influenced the xylitol reaction pathways. The large dependencies of the activities and selectivities on the H2pressures, reaction temperatures, and pH values showed their effects on the relative rates for the hydrogenation and base-catalyzed reactions involved in xylitol hydrogenolysis, reflecting the bifunctional nature of the xylitol reaction pathways. These results led to the proposition that xylitol hydrogenolysis to ethylene glycol and propylene glycol apparently involves kinetically relevant dehydrogenation of xylitol to xylose on the metal surfaces, and subsequent base-catalyzed retro-aldol condensation of xylose to form glycolaldehyde and glyceraldehyde, followed by direct glycolaldehyde hydrogenation to ethylene glycol and by sequential glyceraldehyde dehydration and hydrogenation to propylene glycol. Clearly, the relative rates between the hydrogenation of the aldehyde intermediates and their competitive reactions with the bases dictate the selectivities to the two glycols. This study provides directions towards efficient synthesis of the two glycols from not only xylitol, but also other lignocellulose-derived polyols, which can be achieved, for example, by optimizing the reaction parameters, as already shown by the observed effects of the catalysts, pH values, and H2pressures. [ABSTRACT FROM AUTHOR]

A concise and efficient synthetic route to 4,5-fused tricyclic 2-quinolones through the palladium-catalyzed carbonylative annulation of alkyne-tethered N-substituted o-iodoanilines has been developed. This reaction proceeds smoothly under mild reaction conditions and exhibits exceptional tolerance to a variety of functional groups. It has been successfully applied to the efficient synthesis of BI 224436, an HIV integrase inhibitor. [ABSTRACT FROM AUTHOR]

H5PV2Mo10O40 polyoxometallate Keggin clusters supported on ZrO2, TiO2, SiO2, and Al2O3 are effective catalysts for CH3OH oxidation reactions to form HCHO, methyl formate (MF), and dimethoxymethane (DMM). Rates and selectivities and the structure of supported clusters depend on the surface properties of the oxide supports. Raman spectroscopy showed that Keggin structures remained essentially intact on ZrO2, TiO2, and SiO2 after treatment in air at 553 K, but decomposed to MoOx and VOx oligomers on Al2O3. Accessible protons per Keggin unit (KU) were measured during CH3OH oxidation by titration with 2,6-di-tert-butyl pyridine. For similar KU surface densities (0.28–0.37 KU/nm2), the number of accessible protons was larger on SiO2 than on ZrO2 and TiO2 and much smaller on Al2O3 supports, even though residual dimethyl ether (DME) synthesis rates after titrant saturation indicated that the fractional dispersion of KU was similar on the first three supports. These effects of support on structure and on H+ accessibility reflect varying extents of interaction between polyoxometallate clusters and supports. Rates of CH3OH oxidative dehydrogenation per KU were higher on ZrO2 and TiO2 than on SiO2 at similar KU surface densities (0.28–0.37 KU/nm2) and dispersion, indicating that redox properties of Keggin clusters depend on the identity of the support used to disperse them. ZrO2 and TiO2 supports appear to enhance the reducibility of anchored polyoxometallate clusters. Rates were much lower on Al2O3, because structural degradation led to less reactive MoOx and VOx domains. CH3OH reactions involve primary oxidation to form HCHO and subsequent secondary reactions to form DMM and MF. These reactions involve HCHO–CH3OH acetalization steps leading to methoxymethanol (CH3OCH2OH) or hemiacetal intermediates, which condense with CH3OH on acid sites to form DMM or dehydrogenate to form MF. COx formation rates are much lower than those of other reactions, and DME forms in parallel pathways catalyzed by acid sites. Secondary reactions leading to DMM and MF are strongly influenced by the chemical properties of support surfaces. Acidic SiO2 surfaces favored DMM formation, while amphoteric or dehydrogenating surfaces on ZrO2 and TiO2 led to MF formation, as a result of the varying role of each support in directing the reactions of HCHO and CH3OH and of the CH3OCH2OH intermediates toward DMM or MF, which was confirmed using physical catalyst–pure support mixtures. These support effects reflect the bifunctional pathways of CH3OH reactions. These pathways are consistent with the effects of residence time and of the partial removal of H+ sites by titration using 2,6-di-tert-butyl pyridine. [Copyright &y& Elsevier]

The selective oxidation of dimethyl ether (CH3OCH3) to formaldehyde (HCHO) was carried out on MoOx species with a wide range of MoOx surface density and structure supported on MgO, Al2O3, ZrO2, and SnO2. Raman and X-ray absorption spectroscopies were used to probe the structure of these MoOx domains, as they evolved from monomeric species into two-dimensional polymolybdate domains and MoO3 clusters with increasing MoOx surface density. Primary HCHO synthesis rates (per Mo atom) initially increased with increasing MoOx surface density (1.5–7 Mo/nm2) on all supports, indicating that MoOx domain surfaces become more active as two-dimensional monolayers form via oligomerization of monomer species. The incipient formation of MoO3 clusters at higher surface densities led to inaccessible MoOx species and to lower HCHO synthesis rates (per Mo). Areal rates reached constant values as polymolybdate monolayers formed. These areal rates depend on the identity of the support; they were highest on SnO2, lowest on Al2O3, and undetectable on MgO, indicating that the surface properties of polymolybdate structures are strongly influenced by their atomic attachment to a specific support. The catalytic behavior of MoOx domains reflects their ability to delocalize electron density during the formation of transition states required for rate-determining C&z.sbnd;H bond activation steps within redox cycles involved in HCHO synthesis from dimethyl ether. These conclusions are consistent with the observed parallel increase in the rates of HCHO synthesis and of incipient stoichiometric reduction of MoOx domains by H2 as the domain size increases and as the supports become less insulating and more reducible, and as the energy required for ligand-to-metal electronic transitions in the UV–visible spectrum decreases. HCHO selectivities increased with increasing MoOx domain size; they were highest on Al2O3 and lowest on SnO2 supports. The Lewis acidity of the support cations appears to influence HCHO binding energy. HCHO reactions leading to COx and methyl formate via primary and secondary pathways are favored on weaker Lewis acids (with stronger conjugate bases). The Mo&z.sbnd;O–support linkages prevalent at low surface densities also favor primary and secondary pathways to COx and methyl formate. When reported on a CH3OH-free basis, because of the pathways available for CH3OH oxidation to HCHO and for CH3OCH3&z.sbnd;CH3OH interconversion, primary HCHO selectivities reached values greater than 95% on Al2O3-supported polymolybdate monolayers. [Copyright &y& Elsevier]

MoOx species dispersed as small domains on Al2O3, ZrO2, and SnO2 catalyze the oxidative conversion of dimethylether to formaldehyde with high primary selectivity (80–98% HCHO, CH3OH-free basis) at low temperatures (500–550 K). The reaction appears to proceed via redox cycles using lattice oxygen and turnover rates increase with the size and reducibility of MoOx domains. Dimethylether conversion rates (per g) and formaldehyde selectivities at 513 K are significantly higher than those reported previously on various catalysts at significantly higher temperatures (620–880 K). [Copyright &y& Elsevier]

The cocrystals of 2‐(benzo[d]thiazol‐2‐yl)‐3‐(pyren‐1‐yl)acrylonitrile (Py‐BZTCN) and 1,2,4,5‐tetracyanobenzene (TCNB) are constructed through intermolecular charge‐transfer (CT) interactions between donor and acceptor. Cis‐ and trans‐isomers of Py‐BZTCN induce the formation of two different crystal packing with 1:2 and 1:1 stoichiometric ratios between Py‐BZTCN and TCNB, corresponding to the cocrystals of PCNTC‐O and PCNTC‐R, respectively. PCNTC‐O cocrystal exhibits orange‐yellow normal fluorescence with a CT from pyrene (Py) monomer to TCNB, while PCNTC‐R cocrystal presents red thermally activated delayed fluorescence (TADF) with a CT from Py dimer to TCNB. This photophysical difference originates from that, relative to Py monomer, Py dimer has an elevated energy level of highest occupied molecular orbital (HOMO), which results in a stronger CT in PCNTC‐R cocrystal. Both cocrystals possess unique two‐photon absorption (TPA) properties, and changing monomer into dimer as a donor in the CT cocrystal effectively alters the supramolecular properties. Noteworthily, PCNTC‐R is a rare case in which TADF and TPA are integrated into a cocrystal, opening up a new supramolecular strategy to explore the multi‐functional materials. [ABSTRACT FROM AUTHOR]

Recycling flexible polyurethane foam (F-PUF) scraps is difficult due to the material's high cross-linking structure. In this work, a wedge-block-reinforced extruder with a considerable enhanced shear extrusion and stretching area between the rotating screw and the stationary wedge blocks was utilized to recycle F-PUF scraps into powder containing surface-active hydroxyl groups. The powder was then utilized for the quantitative replacement of polyol in the foaming process. Characterizations showed that the continuous shear extrusion and stretching during the extrusion process reduced the volume mean diameter (VMD) of the F-PUF powder obtained by extruding it three times at room temperature to reach 54 μm. The -OH number (OHN) of the powder prepared by extruding it three times reached 19.51 mgKOH/g due to the mechanochemical effect of the powdering method. The F-PUF containing recycled powder used to quantitively replace 10 wt.% polyol was similar in microstructure and chemical structure to the original F-PUF, with a compression set of 2%, indentation load deflection of 21.3 lbf, resilience of 43.4%, air permeability of 815.7 L/m2·s, tensile strength of 73.0 Kpa, and tear strength of 2.3 N/cm, indicating that the recycling method has potential for industrial applications. [ABSTRACT FROM AUTHOR]

Developing materials with dynamic room-temperature phosphorescence (RTP) properties is crucial for expanding the applications of organic light-emitting materials. In this study, we designed and synthesized two novel RTP molecules by combining functional units, incorporating the folded unit thianthrene into the classic luminescent cores thioxanthone or anthraquinone to construct TASO and TA2O. In this combination, the TA unit contributes to the enhancement of spin–orbit coupling (SOC), while the luminescent core governs the triplet energy level. After the strategic manipulation of SOC using the thianthrene unit, the target molecules exhibited a remarkable enhancement in RTP performance. This strategy led to the successful development of TASO and TA2O molecules with outstanding dynamic RTP properties when exposed to continuous ultraviolet irradiation, a result that can be ascribed to their efficient RTP, improved absorption ability, and oxygen-sensitive RTP properties. Leveraging the oxygen-mediated ultraviolet-radiation-induced RTP enhancement in TASO-doped polymer films, we developed a novel time-resolved detection technique for identifying phase separation in polymers with varying oxygen permeability. This research offers a promising approach for constructing materials with dynamic RTP properties. [ABSTRACT FROM AUTHOR]

The mixer is the most widely used batch mixing equipment in the rubber industry. The rotor is a core component and has a great impact on the mixing effect of the equipment. The current rotor structure design is done empirically, being tightly dependent on practical experience. This paper proposes a method for optimizing the rotor structure by using optimization algorithms combined with numerical simulation technology. Using MATLAB software, a parametric design program for synchronous rotors and a set of optimization programs for the particle swarm optimization (PSO) algorithm were written. The global distribution index was used as the fitness function to optimize the synchronous rotor configuration. A comparative analysis of the rotors before and after optimization shows that the optimization process is feasible, and the results are reliable. This provides new ideas for the design and development of mixer rotors. [ABSTRACT FROM AUTHOR]

Hole transporting material (HTM)-free carbon-based perovskite solar cells (C–PSCs) have attracted widespread attention for their notable characteristics of excellent long-term stability and low cost. However, the power conversion efficiency (PCE) of C–PSCs is significantly lower than that of HTM-based PSCs. This is mostly due to the unexpected electron recombination happening at the interface of perovskite/carbon. In this study, biomass-based carbon materials were obtained from discarded soybean dregs with sufficient pore size and good conductivity through programmed temperature carbonization and KOH activation processes. Composites of KOH-activated soybean dregs carbon and conductive carbon were used as the counter electrodes (CEs) of C–PSCs, the electrode interface performance was significantly improved and a PCE of 12.05% was obtained, which was 50% higher than that of pure carbon-based C–PSCs. Through long-term stability tests, it was found that the efficiency of the unpackaged cell did not decrease in after 960 h in the air. Composites of KOH-activated soybean dregs carbon and conductive carbon paste were used as the CEs of C–PSCs, combined with the grinding process, the electrode interface performance was significantly improved. Image 1 • Obtained porous compressible biomass-based carbon from discarded bean dregs. • Improved interfacial performance by using biomass soybean residue carbon as CEs. • A PCE of 12.05% was obtained using biomass soybean residue carbon as CEs. • Incorporation of biomass-based carbon is helpful to suppress charge recombination. [ABSTRACT FROM AUTHOR]