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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]

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]

• 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]

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]

[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]

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]

Citric acid is an important biomass-derived platform chemical for the synthesis of high-value organic acids, such as itaconic acid (ICA), 2-methylsuccinic acid (MSA) and tricarballylic acid (TCA). However, these reactions frequently encounter low efficiency and severe leaching of catalysts imposed by the acidity of citric acid under hydrothermal conditions, limiting their practical applications. Here, we report that highly acid- and etching-resistant monoclinic zirconium dioxide (m-ZrO2) exhibited high catalytic efficiency in the conversion of citric acid to ICA via sequential dehydration and decarboxylation steps, providing a high yield of 70.3% at 180 °C on m-ZrO2 (calcined at 300 °C). The correlation between the activity of the m-ZrO2 catalysts and their acid-basicity demonstrates that the synergistic effect of acidic and basic sites facilitates the rate-determining dehydration step for the citric acid conversion to ICA. On the bifunctional catalysts, Pt and Pd nanoparticles supported on P25 and anatase TiO2, citric acid can be selectively converted to MSA and TCA, respectively, with yields as high as 83.1% and 64.9%. The hydrogenation activity of the bifunctional catalysts was found to be crucial for regulating the relative rates of the decarboxylation and hydrogenation steps involved in the selective conversion of citric acid to MSA and TCA. These catalysts showed excellent stability and recyclability in acidic aqueous solutions. This study provides a rationale for tuning catalytic functions required for the green production of important carboxylic acids from citric acid and other biomass-derived feedstocks. [ABSTRACT FROM AUTHOR]

The role of Pleckstrin homology-like domain family B member 2 (PHLDB2) in the regulation of cell migration has been extensively studied. However, the exploration of PHLDB2 in head and neck squamous cell carcinoma (HNSCC) is still limited in terms of expression, function, and therapeutic potential. In this study, we discovered an upregulation of PHLDB2 expression in HNSCC tissues which was correlated with a negative prognosis in patients with HNSCC. Additionally, we determined that a high level of expression of PHLDB2 is crucial for maintaining cell migration through the regulation of the epithelial–mesenchymal transition (EMT). Furthermore, we demonstrated that the ablation of PHLDB2 in tumor cells inhibited tumorigenicity in a C3H syngeneic tumor-bearing mouse model. Mechanistically, PHLDB2 was found to be involved in the regulation of T cell anti-tumor immunity, primarily by enhancing the activation and infiltration of CD8+ T cells. In light of these findings, PHLDB2 emerges as a promising biomarker and therapeutic target for interventions in HNSCC. [ABSTRACT FROM AUTHOR]

Low-temperature mechanical chemical devulcanization is a process that can produce reclaimed rubber with exceptional mechanical properties. However, the inadequacy and low efficiency of the devulcanization have significantly restricted its application. To address the issues, alcoholic amines, including hydroxyethyl ethylenediamine (AEEA), ethanolamine (ETA), and diethanol amine (DEA), are utilized as devulcanizing agents to promote the devulcanization process. Careful characterizations are conducted to reveal the devulcanizing mechanism and to depict the performances of reclaimed rubbers. Results show that the amine groups in the devulcanizing agents can react with sulfur after the crosslink bonds are broken by mechanical shear force, thus blocking the activity of sulfur and introducing hydroxyl groups into the rubber chains. The incorporation of alcoholic amines can enhance the devulcanizing degree and devulcanizing efficiency, reduce the Mooney viscosity, and improve the mechanical and anti-aging performance. When using DEA as the devulcanizing agent, the sol content of reclaimed rubber increases from 13.1% to 22.4%, the devulcanization ratio increases from 82.1% to 89.0%, the Mooney viscosity decreases from 135.5 to 83.6, the tensile strength improves from 14.7 MPa to 16.3 MPa, the retention rate of tensile strength raises from 55.2% to 82.6% after aging for 72 h, while the devulcanization time is shortened from 21 min to 9.5 min, compared with that without using alcoholic amines. Therefore, alcoholic amines exhibit remarkable advantages in the devulcanization of waste rubber, thus indicating a promising direction for the advancement of research in the area of waste rubber reclamation. [ABSTRACT FROM AUTHOR]

Plastic waste is globally ubiquitous and ecologically harmful, but it can be recycled as an abundant carbon source to alleviate worldwide heavy dependence on fossil resources and reduce CO2 emissions. Therefore, research into the chemical recycling of plastic waste has become a critical and pressing area. Compared with polyolefins, polyesters, as represented by PET and PLA, can easily achieve selective depolymerization to their corresponding monomers due to the presence of weaker ester bonds, thus favoring their closed-loop recycling and upcycling. However, comprehensive reviews on this important topic remain scarce, especially from the standpoint of re/upcycling. In this review, we present significant progress in the catalytic depolymerization of different polyesters, including biodegradable polyesters and nonbiodegradable polyesters, and discuss the key factors that limit the efficacies of the different methods and formidable challenges towards closed-loop recycling and upcycling. Such insightful discussion may benefit the further development of advanced strategies to address the problems with the increasing polyester plastic wastes and stimulate their efficient recycling to value-added chemicals and materials. [ABSTRACT FROM AUTHOR]

The structure–property relationship is always the focus when organic light-emitting materials are used mainly in the aggregated state in some fields, such as optoelectronic devices, sensors, and bioimaging. To clarify a clear structure–property relationship between the aggregate structure and the luminescent property, the intermolecular dimer, which represents the smallest aggregate in a number, is selected as an ideal research model. However, how to achieve an intermolecular dimer by a rational molecular design is rarely found in previous papers in this field. Here, we design and synthesize three pyrene derivatives, aiming at achieving the pyrene-based dimer in a solid state, by bridging pyrene and benzo[d]thiazole (BZT) in a different position on a phenylene. The pyrene and BZT groups are connected with each other in the ortho-, meta-, and para-positions of the phenylene to construct three molecules Py-oBZT, Py-mBZT, and Py-pBZT. Experimental and theoretical investigations demonstrate that only Py-oBZT shows pyrene-based dimer stacking with a discrete feature due to the large steric hindrance provided by the BZT group. Compared to individual pyrenes in the crystal, the pyrene-based dimer in the Py-oBZT crystal exhibits a different molecular orientation, which is verified by the presence of multiple potential wells of the pyrene dimer using a theoretical simulation of the potential energy surface. This work not only examines the effect of steric hindrance on the formation of the pyrene dimer packing, but also provides an understanding of the multiplicity of the pyrene dimer structures. [ABSTRACT FROM AUTHOR]

In recent years, pure organic room‐temperature phosphorescence (RTP) with highly efficient and long‐persistent afterglow has drawn substantial awareness. Commonly, spin‐orbit coupling can be improved by introducing heavy atoms into pure‐organic molecules. However, this strategy will simultaneously increase the radiative and non‐radiative transition rate, further resulting in dramatic decreases in the excited state lifetime and afterglow duration. Here in this work, a highly symmetric bird‐like structure tetraphenylene (TeP), and its three symmetrical halogenated derivatives (TeP−F, TeP−Cl and TeP−Br) are synthesized, while their RTP properties and mechanisms are systematically investigated by both theoretical and experimental approaches. As the results, the rigid, highly twisted conformation of TeP restricts the non‐radiative processes of RTP and gives rise to the enhancement of electron‐exchange, which can contribute to the RTP radiation process. Despite the faint RTP of the bromine and chlorine‐substituted ones (TeP−Br, TeP−Cl), the fluoro‐substituted TeP−F exhibited a long phosphorescent lifetime up to 890 ms, corresponding to an extremely long RTP afterglow over 8 s, which could be incorporated into the best series of non‐heavy‐atom RTP materials reported in previous literature. [ABSTRACT FROM AUTHOR]

In recent years, pure organic room‐temperature phosphorescence (RTP) with highly efficient and long‐persistent afterglow has drawn substantial awareness. Commonly, spin‐orbit coupling can be improved by introducing heavy atoms into pure‐organic molecules. However, this strategy will simultaneously increase the radiative and non‐radiative transition rate, further resulting in dramatic decreases in the excited state lifetime and afterglow duration. Here in this work, a highly symmetric bird‐like structure tetraphenylene (TeP), and its three symmetrical halogenated derivatives (TeP−F, TeP−Cl and TeP−Br) are synthesized, while their RTP properties and mechanisms are systematically investigated by both theoretical and experimental approaches. As the results, the rigid, highly twisted conformation of TeP restricts the non‐radiative processes of RTP and gives rise to the enhancement of electron‐exchange, which can contribute to the RTP radiation process. Despite the faint RTP of the bromine and chlorine‐substituted ones (TeP−Br, TeP−Cl), the fluoro‐substituted TeP−F exhibited a long phosphorescent lifetime up to 890 ms, corresponding to an extremely long RTP afterglow over 8 s, which could be incorporated into the best series of non‐heavy‐atom RTP materials reported in previous literature. [ABSTRACT FROM AUTHOR]

• Pd/ m- Al 2 O 3 -Si catalyst exhibited high efficiency in converting α- amino -ε- caprolactam (α- ACL) to dimethyl-protected cyclic lysine (DMCL). • The lack of Brönsted acid sites on Pd/ m- Al 2 O 3 -Si surface facilitated the formation of DMCL and suppressed undesirable reaction process. • Pd/ m- Al 2 O 3 -Si catalyst with microspherical morphology performed excellent stability and physical strength during the catalytic process. • The nylon‑6 copolymers produced from the as-synthesized DMCL exhibited a great potential in the synthesis of self-cleaning antibacterial materials. Antibacterial monomers are prerequisites for synthesizing antibacterial polymers, especially during the current COVID-19 pandemic. Dimethyl-protected cyclic lysine (DMCL) is a promising functional monomer for nylon-6 based self-cleaning antibacterial polymers. However, the production of DMCL still faces formidable challenges, such as harsh reaction conditions and low catalyst activities. In this study, we developed a Pd/ m -Al 2 O 3 -Si catalyst, which exhibited high efficiency in converting α -amino- ε -caprolactam (α -ACL) to DMCL, affording a yield of as high as 97.1% at 100 °C and 1 MPa H 2. The lack of Brönsted acid sites on the catalyst surface facilitated the formation of DMCL and suppressed undesirable hydrolysis or cracking by-products from the lactam-based reactant. The recycled experiments showed that Pd/ m -Al 2 O 3 -Si performed excellent stability and physical strength with essentially no damage to its microspheres after the reaction. The nylon‑6 copolymers produced from the as-synthesized DMCL exhibited similar structure and thermal stability with pure nylon-6, showing great potential in synthesizing the self-cleaning antibacterial polymers. This work provides a sustainable and efficient method for producing DMCL and other lysine-based antibacterial monomers, showing a great prospect for the utilization of bio-based chemicals in synthesizing functional polymers. [ABSTRACT FROM AUTHOR]

Photo‐assisted reverse water gas shift (RWGS) reaction is regarded green and promising in controlling the reaction gas ratio in Fischer Tropsch synthesis. But it is inclined to produce more byproducts in high H2 concentration condition. Herein, LaInO3 loaded with Ni‐nanoparticles (Ni NPs) was designed to obtain an efficient photothermal RWGS reaction rate, where LaInO3 was enriched with oxygen vacancies to roundly adsorbing CO2 and the strong interaction with Ni NPs endowed the catalysts with powerful H2 activity. The optimized catalyst performed a large CO yield rate (1314 mmol gNi−1 h−1) and ≈100 % selectivity. In situ characterizations demonstrated a COOH* pathway of the reaction and photoinduced charge transfer process for reducing the RWGS reaction active energy. Our work provides valuable insights on the construction of catalysts concerning products selectivity and photoelectronic activating mechanism on CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

Photo‐assisted reverse water gas shift (RWGS) reaction is regarded green and promising in controlling the reaction gas ratio in Fischer Tropsch synthesis. But it is inclined to produce more byproducts in high H2 concentration condition. Herein, LaInO3 loaded with Ni‐nanoparticles (Ni NPs) was designed to obtain an efficient photothermal RWGS reaction rate, where LaInO3 was enriched with oxygen vacancies to roundly adsorbing CO2 and the strong interaction with Ni NPs endowed the catalysts with powerful H2 activity. The optimized catalyst performed a large CO yield rate (1314 mmol gNi−1 h−1) and ≈100 % selectivity. In situ characterizations demonstrated a COOH* pathway of the reaction and photoinduced charge transfer process for reducing the RWGS reaction active energy. Our work provides valuable insights on the construction of catalysts concerning products selectivity and photoelectronic activating mechanism on CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

Noncovalent fluorescence switching materials with specific molecular packing motifs for desired performance are difficult to design accurately due to the complexity of intermolecular interactions. Herein, a noncovalent interaction competition strategy to design fluorescence‐switching materials by fine‐modulating hydrogen‐bond and π–π interactions is proposed. Hydrogen bonds are generated by nitrogen/oxygen‐containing units while π–π interactions are generated between polycyclic aromatic hydrocarbons. After these two interactions are balanced in strength, they attempt to induce the formation of respective molecule assemblies stably under controllable conditions. Through thermal stimulus produced by a laser, a reversible assembly transition with high‐contrast monomer‐to‐excimer fluorescence switching is achieved, which demonstrates promising applications in rewritable optical recording and time‐dependent anti‐counterfeiting. This strategy provides a crucial step toward the controllable switching of supramolecular assembly for information handling. [ABSTRACT FROM AUTHOR]

The accessibility and adjustability of the brake system pressure give more control freedom to the vehicle dynamics control. Pneumatic braking system works as the most common form in vehicles, whose overall model is the basis for pressure estimation and control. This paper analyzes the coupling relationship of the relay valve, ABS valve, pipeline and braking cylinder in the pneumatic braking system. The dynamic performances of each component including the electrical, electromagnetic, mechanical and fluid performance are studied. In the fluid modeling, the distributed model is proposed further for describing the behavior of compressible gas in pipelines. Next, the pressure estimation algorithm and the rule-based pressure control strategy are designed based on the proposed model. Finally, the proposed model and strategy is verified in bench and vehicle experiments. The results show that the models are able to represent the behavior of the typical pneumatic braking system, and the pressure estimation and control based on it meets the application needs of real vehicles. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to assess the epidemiological features and explore the potential risk factors for early neurological deterioration (END) in patients with acute single small subcortical infarction (SSSI) who underwent antiplatelet therapy without carotid artery stenosis. Materials & methods: Patients with SSSI, as confirmed by cranial magnetic resonance imaging (MRI), who were hospitalized within 48 h after the onset of symptoms were enrolled. END was mainly defined as increment in the National Institutes of Health Stroke Scale (NIHSS) score of ≥ 2 points or any new neurological deficit. Poor functional outcome was defined as modified Rankin Scale (mRS) score of > 2 points at 3-month after the onset. The association of END with multiple indicators was assessed at the early stage of admission using multivariate logistic regression analysis, and adjusted odds ratios (aORs) were calculated. Results: A total of 280 patients were enrolled from June 2020 to May 2021, of whom, END occurred in 44 (15.7%) patients (median age, 64 years; 70.5% male), while END occurred during sleep in 28 (63.6%) patients. History of hypertension (aOR: 4.82, p = 0.001), infarction in internal capsule (aOR: 3.35, p = 0.001), and elevated level of low-density lipoprotein cholesterol (LDL-C; aOR: 0.036, p = 0.0016) were significantly associated with the risk of END. Patients with END (aOR: 5.74, p = 0.002), history of diabetes (aOR: 2.61, p = 0.020), and higher NIHSS scores at discharge (per 1-score increase, aOR: 1.29, p = 0.026) were associated with the poor functional outcome at 3-month after the onset. Conclusion: Patients with a history of hypertension, infarction in internal capsule or a higher level of LDL-C were found to be at a higher risk of END. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT), as reinforcing agents in natural rubber (NR), has gained a large amount of consideration due to their excellent properties. Uniform dispersion of CNT is the key to obtaining high-performance NR nanocomposites. In this contribution, a novel ultrasonic grinding dispersion method of CNT with waterjet-produced rubber powder (WPRP) as a carrier is proposed. Microscopic morphologies show that a Xanthium-like structure with WPRP as the core and CNTs as the spikes is formed, which significantly improves the dispersion of CNT in the NR matrix and simultaneously strengthens the bonding of the WPRP and NR matrix. With the increase in the WPRP loading, the Payne effect of CNT/WPRP/NR composites decreases, indicating the effectiveness of the dispersion method. The vulcanization MH and ML value and crosslinking density increase with the increase in the WPRP loading, whereas the scorch time and cure time exhibit a decreasing trend when the WPRP loading is less than 15 phr. It is found that the CNT/WPRP/NR composites filled with 5 phr WPRP have a 4% increase in 300% modulus, a 3% increase in tensile strength, while a 5% decrease in Akron abrasion loss, compared to CNT/NR composites. [ABSTRACT FROM AUTHOR]

Objectives: To identify independent factors for head and neck cancer (HNC) patients with carotid blowout syndrome (CBS) and construct a nomogram to predict risk of CBS preoperatively based on computed tomography angiography (CTA) imaging. Subject and Methods: From January 2010 to July 2020, 73 HNC patients who had surgery in hospitalization and underwent CTA examination for head and neck region were included in this study. Vascular alterations and the relationship between carotid artery (CA) and tumor were evaluated in CTA. Clinical and CTA imaging features were distinguished by logistic regression analysis and used to perform receiver operating curve analysis. Nomogram was created to predict risk of CBS and assessed by concordance index (C‐index) and calibration curve. Results: Three independent risk factors were identified, including radical neck dissection, CA surrounded by tumor, and CA invaded by tumor without clear boundary. Area under curve of the combination of 3 variables was 0.836 (95% CI, 0.72–0.952, p < 0.001). The C‐index of nomogram was 0.84 (95% CI, 0.73–0.94), and the calibration plot showed a good fitting between prediction and observation. Conclusions: We established a useful nomogram based on CTA imaging, which showed a satisfied efficacy for evaluating risk of CBS in HNC patients preoperatively. [ABSTRACT FROM AUTHOR]

In the context of protecting the ecological environment and carbon neutrality, high-value recycling of flexible polyurethane foam (F-PUF) scraps, generated in the production process, is of great significance to save petroleum raw materials and reduce energy consumption. In the present study, F-PUF scraps were ground into powder by strong shear regrinding using two-roll mill and then reused as a partial replacement of polyol for re-foaming. A series of characterizations were employed to investigate the effect of milling cycles, roller temperatures, and content of the powder on the properties of the powder and F-PUF containing powder. It was revealed that the mechanochemical effect induced breaking of the cross-linking structure and increased activity of the powder. The volume mean diameter (VMD) of powder prepared with 7 milling cycles, at room temperature, is about 97.73 μm. The microstructure and density of the F-PUF containing powder prepared in the above-mentioned manner to replace up to 15 wt.% polyol, is similar to the original F-PUF, with resilience 49.08% and compression set 7.8%, which indicates that the recycling method will play an important role in industrial applications. [ABSTRACT FROM AUTHOR]

We have synthesized two novel amide-based organic friction modifiers(OFMs), namely NIPAOA and NDEAOA, through the addition reaction of oleamine with N-isopropylacrylamide and N, N-dimethylacrylamide. The two OFMs exhibit good solubility in PAO6 base oil. Their tribological performance has been investigated using a line contact both individually and when compounded with the anti-wear additive zinc dialkyldithiophosphate (ZDDP) at temperatures ranging from 40 ℃ to 130 ℃. The results show that NIPAOA and NDEAOA form dual-site adsorption on the tribo-pair surface through the N and O atoms in the head group amide, resulting in the tribo-film exhibiting excellent friction-reducing performance in PAO6 across the temperatures. When compounded with ZDDP, they both exhibit effective synergistic friction-reducing effects, attributed to the formation of a unique tribo-chemical reaction film on the worn surface that contains almost no Fe and its compounds. The formation of the unique tribo-film is partly due to the continuous adsorption of free OFMs on the surface of the formed ZDDP tribo-film, providing a milder contact environment for the tribo-pair, allowing for the continuous polymerization of medium and long-chain zinc dialkyldithiophosphate (ZDDP) to ultimately form a uniform and flat tribo-chemical reaction film which interspersed with nitrogen-containing compounds. Even after long-term testing, the film maintains good stability and abrasion resistance, effectively synergizing friction-reducing and anti-wear properties. [ABSTRACT FROM AUTHOR]

In this study, a novel capacitance based analytical method to monitor the film thickness in a ball bearing under a combination of axial and radial load is presented. Furthermore, an extended method is presented to infer the difference between the lubricant film height on the inner ring and the outer ring of a rolling element. Numerical investigations provide the basis for describing the influence of the operating parameters on the lubricant film thickness distribution in the HERTZ'ian contact. The method for calculating the correction factor k c presented in a previous paper is extended so that it is valid for a wider operating range. This makes it possible to calculate the total capacitance of a contact from the capacitance of only the HERTZ'ian contact area. • Extension of Capacitance Formulae for Point Contact. • Formula to Calculate Film Thickness Distribution under Combined Load Cases from Capacitance Measurements. • Analytical Formula to Predict the Film Thickness Distribution between the Rolling Element and the Inner and Outer Ring. [ABSTRACT FROM AUTHOR]

A pyrene-based non-covalent dimer in a crystal showed a strengthened π–π interaction, which was robust enough against external disturbances. Such a strong π–π interaction made the pyrene-based dimer easily form in the amorphous film, indicating that the dimer could potentially work as the monomer. [ABSTRACT FROM AUTHOR]

Objective. The aim of this study was to investigate the efficacy and safety of bladder flap ureteroplasty (psoas hitch) in the treatment of lower ureteral injuries and strictures. Methods. 19 patients with lower ureteral injuries and strictures scheduled for a bladder flap ureteroplasty (psoas hitch) in our hospital from January 2020 to January 2021 were recruited. The outcome measures included treatment efficacy and safety. Results. The operative time, intraoperative bleeding, catheter extubation time, hospital stay, extubation time of ureteral stent, and follow-up time were (125.36 ± 15.38) min, (75.37 ± 11.09) ml, (7.25 ± 1.04) d, (8.76 ± 1.11) d, (46.34 ± 7.66) d, and(19.27 ± 1.27) months, respectively. No serious perioperative adverse reactions were observed, and all the symptoms of patients were relieved. Conclusion. Bladder flap ureteroplasty (psoas hitch) is safe and effective for the treatment of lower ureteral injuries, with advantages such as less intraoperative bleeding and trauma and rapid recovery, so it is worthy of promotion. This was a retrospective study supervised by the Ethics Committee of Hebei Yanda Hospital.This trial is registered with no. hebYD076. [ABSTRACT FROM AUTHOR]

Low and medium temperature pyrolysis technology is an important way of clean and utilization of low metamorphic coal. In this paper, three kinds of char samples were prepared in tube furnace according to different pyrolysis temperatures, and their combustion characteristics were compared by means of thermal analysis. Three modeless kinetic methods, KAS, FWO and Fredman, were used to study the combustion reaction activity under nonisothermal conditions from TG curve and DSC curve. In the end, Malek method is used to explore the mechanism function of the reaction process, and the results are analyzed numerically. The objective programming model and MATLAB are used to calculate the combined mechanism function of the reaction process. The results show that with the increase in the pyrolysis temperature, the combustion of char gradually shifts to the high temperature zone and shows a secondary effect between the volatile matter and the combustion characteristic temperature. The results show that the flammability index and burnout index increase first and then decrease, and the char prepared at 550 °C has the most developed pores and the best combustion performance with the increase in pyrolysis temperature, the average reaction activation energy decreases first and then increases, and the char prepared at 550 °C has the lowest activation energy. When the combustion heating rate is 5 °C min−1, the experimental curve and theoretical curve have a higher coincidence, and the combined mechanism function is adopted. The number is more suitable than the single most probable mechanism function to describe the combustion process of char. At this heating rate, the fuel reaction conforms to Z–L–T equation and reaction order model, which is limited by three-dimensional diffusion and chemical reaction. The distribution coefficients of the combined mechanism function are 0.4207 and 0.5886. [ABSTRACT FROM AUTHOR]

Studies show that long‐term operation of the rubber mixer results in wear at the end face of the mixer. End face wear increases the gap between the mixing chamber and the end face, which results in leakage and reduces the mixing performance, thereby affecting the quality of the final product. Therefore, it is of significant importance to investigate the wear of metal face during the mixing process. In the present study, calcium powder was added to the rubber compound using a mechanical blender to obtain a composite material. Then the influence of the calcium powder on metal friction and wear of the end face of the mixer was analyzed. The obtained results show that the calcium powder has anti‐friction properties, which can greatly reduce the compound wear on the metal. The lowest corrosion and wear of the compound on the metal was achieved with 5 phr of calcium powder. Meanwhile, it is found that the tensile and tear‐resistance properties of the compound with 5 phr of calcium powder are slightly lower than those without calcium powder. However, the compound with 5 phr of calcium powder has higher friction, cold resistance, wet slip resistance, and lower rolling resistance. [ABSTRACT FROM AUTHOR]

Excimer materials are frequently applied to organic chemistry, optoelectronic devices and stimulus response. Specific research on the entire process of excimer generation in solid materials, as well as the intricate mechanism of piezochromic luminescence based on excimer, are still absent and need to be examined in-depth through comprehensive experiments. Therefore, we designed an anthracene-based molecule CZPAN , which adopts no overlap area between anthracene molecules in its crystal at ambient conditions, to investigate the piezochromic luminescence behavior and expect the anthracene group to form excimers under high-pressure stimulation. As pressure increases, CZPAN gradually changes from blue monomer luminescence to green excimer luminescence accompanied with the considerably red-shifted emission spectra, and exhibits a discontinuity of fluorescence quenching during the formation of excimers (in the pressure range of 5.3–6.6 GPa). Moreover, the pressure relief process is fully reversible. This study presents abundant piezochromic luminescence of CZPAN and proves that the formation of excimers requires a certain overlap area between molecules. Pursuing the appropriate strength of π–π interactions will thus be the focus of future research on excimer materials of high luminescence efficiency, so that excimers can be better applied in sensors and imaging devices. [Display omitted] • There are no overlap areas between anthracene molecules in the designed crystal at ambient conditions. • High pressure induces the formation of excimers. • The designed crystal shows abundant phenomena of piezochromic luminescence during compression. • High luminescence efficiency of excimers requires the appropriate strength of π–π interactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Deep-red emissive material TPANZPPICN with AIEE property is synthesized. • The "hot-exciton" mechanism is clearly revealed with MEL experiment. • Doped OLED of TPANZPPICN shows high EQE of 8.0 % at 660 nm. Organic deep-red fluorescent materials have a wide range of applications in organic light-emitting diodes (OLEDs), biological imaging, night-vision equipment, and other fields. Here, we designed and synthesized a new deep-red emissive donor–acceptor (D-A) compound TPANZPPICN , whose non-doped OLED achieves stable pure deep-red electroluminescence (EL) at 692 nm with a maximum external quantum efficiency (EQE) of 2.67 % in non-doped OLED and a maximum EQE of 7.96 % at 660 nm in doped OLED. Magneto-electroluminescence (MEL) measurements reveal a negative response in the doped OLED, which is a significant character of reversed intersystem crossing (RISC) on high-lying excited states. Both theoretical calculations and experimental results confirm that the hot-exciton mechanism is responsible for the high efficiency EL of doped OLED, which proves to be a novel approach to realize the efficient deep-red organic fluorescent OLEDs. [ABSTRACT FROM AUTHOR]

In this paper, two donor (D)-acceptor (A) type of small organic fluorescent molecules (T1 and T2) based on terpyridine group are synthesized, characterized and used as colorimetric/fluorometric dual-channel probes towards diethylchlorophosphate (DCP, the mimic of chemical warfare agent sarin) not only in solution but also in gas phase featuring instantaneous responses, excellent recyclability, high selectivity and sensitivity. Interestingly though the discriminated units of both chemosensors are terpyridine, their fluorescent responded signals are different, which is due to the different electron-donating substituents of T1 and T2 caused the different responded mechanism to DCP. And the possible sensing mechanism was proved by using nuclear magnetic resonance (1H NMR, 31P NMR) spectra and natural transition orbitals calculations. Furthermore, facile testing filter paper-constructed strips with the visualization of colorimetric/fluorometric dual-channel responses based on T1 and T2 have been fabricated for real-time, on-site high selective and sensitive, recyclable monitor of DCP vapor. [Display omitted] • Two novel colorimetric/fluorometric probes are developed to detect Sarin mimic DCP. • Both probes display rapid response, excellent selectivity and reutilization to DCP. • The detection limits of the two probes to DCP vapor are extraordinary low. • The quantitative colorimetric/fluorometric filter paper cards are achieved. [ABSTRACT FROM AUTHOR]

Pure organic multi-color luminescent materials were developed using a supramolecular complex strategy based on a high-efficiency blue-emitting anthracene derivative, in which the emission color can be finely tuned from blue through green to red due to the different co-former compositions and stacking modes in the crystal. Experimental and theoretical investigations demonstrate that the excited-state characteristics are essentially responsible for multi-color fluorescence emission with tunable lifetime and efficiency, corresponding to the different excited-state species (e.g., monomer, excimer-like aggregate and exciplex) in the crystals, respectively. Meanwhile, these supramolecular complexes exhibit intriguing mechanochromic and solvent-induced luminescence switching in the stimuli-responsive field. This work not only provides a better understanding of the structure–property relationship between intermolecular complexes and fluorescence properties, but also suggests a feasible strategy to develop a new class of organic solid-state luminescent materials with multi-color fluorescence. [ABSTRACT FROM AUTHOR]

Vinyl methyl ether (VME) is an important chemical intermediate for the production of functional polymers and fine chemicals. It is primarily produced in industry via the addition of methanol to acetylene, known as Reppe vinylation. However, the requirement for high pressures and caustic bases as catalysts limits its practical applications. Here, we report a novel route for the sustainable synthesis of VME from biomass-derived ethylene glycol dimethyl ether (EGDE) via the methanol elimination reaction catalyzed by CaO-based solid bases at atmospheric pressure. The co-precipitated CaO–MgO catalyst with a Ca/Mg molar ratio of 2 exhibited high efficiency and stability, achieving 100% EGDE conversion and 93.5% selectivity to VME at 400 °C. The strongly basic sites facilitated the formation of VME on the CaO–MgO surfaces, whereas, for comparison, the weakly basic sites on MgO or acidic sites on amphoteric oxides (e.g. CeO2) and solid acids (e.g. H-ZSM-5) were found to promote the degradation of VME. This work provides a viable and sustainable strategy for the synthesis of VME and other high-value vinyl compounds from biomass. [ABSTRACT FROM AUTHOR]

Rational regulation on the hybrid local and charge-transfer (HLCT) excited state is crucial for the optimization of light color, especially those of the blue-emissive materials. In this work, two rigid, orthogonal donor-acceptor (D-A) materials are designed and synthesized using the tripenylamine-phenanthroimidazole backbone donor and triphenyltriazine as the acceptor, with different distance between the donor and acceptor units. The shorter distanced DRZ-TPM forms a typical CT excited state, and its organic light emitting diode (OLED) produced green electroluminescence with maximum external quantum efficiency (EQE max) of 5.0%. To regulate the light color, we inserted a phenyl ring to increase the donor-acceptor distance for a reduced CT component. The new material TRZ-TPM achieves sky-blue electroluminescence at 452 nm with EQE max of 2.5% in doped OLED. Furthermore, TRZ-TPM showed obvious excimer emission in the aggregated state, and the non-doped OLED performed reduced opening-voltage comparing to the doped OLED, owing to the better formation of intermolecular charge-transfer state. Two orthogonal donor-acceptor (D-A) materials are designed and synthesized to investigate both intramolecular and intermolecular effect on the hybrid-local and charge-transfer (HLCT) excited state. The extended D-A distance gives rise to the optimized blue-purity and the dimerization can help lowering the turn-on voltage in organic light emitting diode (OLED). [Display omitted] • Rigidly, orthogonally linked donor-acceptor structured, hybrid local and charge-transfer (HLCT) materials are synthesized. • Extended donor-acceptor distance weakens the charge-transfer and realizes better blue purity and electrofluorescence. • A special excimer emission phenomenon with its formation mechanism is discovered and explored. [ABSTRACT FROM AUTHOR]

This paper reviewed the recent research advances in the thermal management issues of Proton-Exchange-Membrane-Fuel-Cells (PEMFC) from design and control perspectives. Most of the current research on PEMFC thermal management have focused mainly on two main aspects; the cooling technology and stack cold start. However, PEM fuel cell thermal management involves many other issues such as effective heat-dissipation, temperature-distribution, temperature-control, and parasitic power, which are crucial in the process of thermal management research. The PEMFC temperature control has been weakly explored in the current review papers and thus, it has a potential research gap to be further studied in the area of PEMFC research. In addition, a review of the latest research in fuel cell technology is necessary due to its rapid development, especially with the increasing demand for fuel cell vehicles in recent years. In this paper, the PEMFC heat production, transfer and dissipation, and their related calculation equations are first reviewed. Then, the thermal management of PEMFC is reviewed from two perspectives: (i) the temperature-distribution characteristics inside the PEMFC and the influence of the structural parameters of each component on the heat dissipation and the uniformity of temperature distribution. (ii) The effects of different control strategies on stack temperature-control (Tst) with the evaluation of robustness of each controller. In addition, the coupling relationship between the fan and the pump in the cooling system and parasitic power studies are analyzed. Finally, according to the current research status of the PEMFC thermal management, the directions for further research are proposed. • PEMFC temperature control has been weakly explored in the current review papers • PEMFC heat production, transfer and dissipation with related equations are reviewed • PEMFC thermal management review is focused on temperature distribution and control • The coupling control between the fan and the pump in the cooling system is studied [ABSTRACT FROM AUTHOR]