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The research progress, existing problems and future development of flame retarding modification of bio-based polyurethane are summarized. The work summarized the research status of commonly used methods for preparing bio-based polyurethane, including basic characteristics, application effect and development prospect of various flame retardant agent. At present, vegetable oil-based polyols can effectively replace traditional industrial synthetic petroleum-based polyols as raw materials for the synthesis of bio-based polyurethane. However, there are still some shortcomings in this area that have not been addressed. The defects of polyurethane, such as flammability and smokiness, need to be improved. The practical application conversion rate of research results was not high. The environmental protection and safety performance of bio-based polyurethane can be further improved and enriched. Therefore, more efforts should be put into the above questions, which were all of great significance to the development of polyurethane. The research on retarding modification of polyurethane will have great development space and application value in the future. [ABSTRACT FROM AUTHOR]

Diphenyl carbonate is one of the raw materials used for the synthesis of polycarbonate, and its green and clean production is of great importance to the non-phosgene process for polycarbonate. The production of diphenyl carbonate by transesterification is its representative process route and is considered to be one of the typical examples of a green and sustainable process for chemicals. Since the discovery of the transesterification catalyst for diphenyl carbonate in the 1970s, researchers have been committed to improving its catalytic activity and selectivity and, correspondingly, the reaction engineering process. However, thermodynamic limitations, low activity, low selectivity, and limited stability have been bottlenecks that the transesterification catalyst has not been able to completely overcome, and the improvement of the catalyst is still ongoing. Therefore, this review takes the transesterification reaction of dimethyl carbonate and phenol as a model reaction and, based on a review of the progress in catalyst research on catalytic reaction processes, tries to clarify the structure–activity relationship between catalytic active sites and catalytic performance in homogeneous and heterogeneous catalytic processes and provides an overview of the progress in catalyst synthesis and modification. [ABSTRACT FROM AUTHOR]

The rapid development of digital finance has transformed traditional financial institutions. We investigate the effect and economic consequences of bank digital transformation on corporate financial constraints using data from China. The results show that bank digital transformation alleviates corporate financial constraints by decreasing information search, processing, and verification costs. Furthermore, the effect of bank digital transformation on corporate financial constraints is more pronounced for firms with higher contract intensity, more intangible assets, and poorer external information environment. We also find that bank digital transformation alleviates corporate financial constraints by increasing debt financing. In addition, we show that digital transformation promotes lending by big banks, resulting in the crowding-out effect. Finally, we find that bank digital transformation promotes the flow of credit resources to non-zombie firms, which effectively improves credit allocation efficiency. This paper extends research on digital finance and new structural finance from the perspective of bank digital transformation. [ABSTRACT FROM AUTHOR]

Wood–plastic composites (WPCs) are facing fire hazard when they are used in construction and furniture and need to be treated with fire protection. In this work, polyurethane (PU) was applied to derive simultaneously flame‐retardancy‐improved and mechanically strengthened wood‐polyurethane composites (WPUCs). It was constructed with ammonium polyphosphate (APP) and PU by a simple way. The results showed that a decrease in smoke production in the Cone Calorimeter Test was measured. When the mass of APP is 18% of PU, limiting oxygen index can reach 31.2%. In the combustion test, the peak of heat release rate and total smoke production for WPUCs were, respectively, decreased by 42.1% and 89.7% in the presence of the above ratio of APP and PU. In addition, the results of the functional group test show that PU contains highly reactive ‐NCO which is bonded to the ‐OH and moisture in the wood fiber, resulting in improvement of physical and mechanical properties. The mechanism for the flame retardancy of WPUCs revealed that polyphosphoric acid produced by APP pyrolysis catalyzed PU into the char, and PU was arched by the resulting gases such as NH3 to form the tiny spherical structure, which worked in blocking heat and the exchange of substances. WPUCs with APP prepared by this method are shown to have improved results, and, therefore, it is expected to provide a new strategy for the preparation of flame‐retardant WPCs. [ABSTRACT FROM AUTHOR]

Zr based metallosilicalites, especially Zr‐ß, is promising catalyst for the conversion of ethanol to 1,3‐butadiene, which is considered to be a sustainable alternative to petroleum steam cracking. However it is suffering from deactivation derived from coking and unsatisfied catalytic activity derived from deficient Lewis acidity. For these issues, a dissolution‐recrystallization process through tetraethyl ammonium hydroxide treatment (TEAOH) for enhancing porosity and Lewis acidity of Zr‐ß zeolite was developed in this study. A balance of dissolution and recrystallization existed in this process, which was produced by OH− etching and templating of TEA+ ions, creating additional mesoporosity. Zirconium active sites maintained tetrahedral coordination, while the Lewis acidity was enhanced by creating higher proportion open sites in framework. The recrystallized Zr‐ß exhibited higher catalytic activity and stability in the conversion of ethanol‐acetaldehyde to butadiene due to the compromise of microporosity and mesoporosity, as well as the appropriate enhancement of Lewis acidity. [ABSTRACT FROM AUTHOR]

Egineering running experience shows that with the increase of the operating voltage of the transmission line, the lightning trip rate is increasing. According to theoretical calculation ， UHV transmission lines should be provided with full lightning protection characteristics；however，running experience shows that the lightning withstand level of UHV transmission lines is high，not completely lightning protection; it puts forward higher requirements for lightning protection design of UHV transmission line in China. UHV transmission line is mainly against direct lightning stroke characteristics， one is caused by lightning counterattack trip，the other is the shielding failure of lightning around the line to strike the wound caused by the wire. The lightning fault type identification is based on the micro topography of UHV transmission tower，accumulation of historical data，the development of a more targeted and high voltage transmission line lightning protection scheme is of great significance. In this paper, a real-time identification system based on UV detection technology, which has high accuracy and fast response time, is proposed for lightning fault types of UHV transmission lines, the systems use ultraviolet light to realize online detection of high-voltage transmission line tower nearby lightning, can effective observation tower near lightning discharge, and it has the characteristics of continuous detection, longdistance, no power supply, no contact and no disassembly, it provides an advanced technology for the detection of lightning discharge in UHV transmission line.

BACKGROUND: With the improvements in bioethanol production, the process of converting ethanol to 1,3‐butadiene (ETB) has received substantial scholarly attention, whose industrialization has been constrained by the stability of the catalysts. RESULTS: In this work, the deactivation behavior of Zr‐β zeolite in the process of ethanol/acetaldehyde conversion to 1,3‐butadiene was investigated. In addition, the deactivation kinetics of ETB was studied using an isothermal differential microreactor. A kinetic model was developed and parametrized with the Langmuir–Hinshelwood mechanism, and the intrinsic kinetic equation was derived. The deactivation kinetic model of the ETB reaction was established from the active site content of the catalyst as a function of time on stream. The validity of the kinetic model was tested, and the results were found to be accurate. CONCLUSIONS: Catalyst deactivation was mainly caused by coke species, which are mainly long‐chain unsaturated oxygenated organic compounds and aromatic compounds, covering Lewis acid sites in the microporous channels of the catalyst; nevertheless the zeotype topology and morphology were not destroyed. The kinetic data suggested that the reaction was of first order and the activation energy of the deactivation process was 75.59 kJ mol−1. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Purkinje cells (PCs), as a unique type of neurons output from the cerebellar cortex, are essential for the development and physiological function of the cerebellum. However, the intricate mechanisms underlying the maintenance of Purkinje cells are unclear. The O-GlcNAcylation (O-GlcNAc) of proteins is an emerging regulator of brain function that maintains normal development and neuronal circuity. In this study, we demonstrate that the O-GlcNAc transferase (OGT) in PCs maintains the survival of PCs. Furthermore, a loss of OGT in PCs induces severe ataxia, extensor rigidity and posture abnormalities in mice. Mechanistically, OGT regulates the survival of PCs by inhibiting the generation of intracellular reactive oxygen species (ROS). These data reveal a critical role of O-GlcNAc signaling in the survival and maintenance of cerebellar PCs. [ABSTRACT FROM AUTHOR]

In this work, Ta was firstly reported as an efficient promoter of MgO–SiO2 for the conversion of ethanol and acetaldehyde to 1,3-butadiene. The doping of Ta into MgO–SiO2 forms Ta–O–Si bonds and generates more strong Lewis acid sites, which not only promote the aldol condensation reaction but also significantly facilitate the Meerwein–Ponndorf–Verley reduction, the total conversion around 80% which drops to 65% after 24 h. In addition, the catalyst showed desirable stability in 24 h long-term stability evaluation, the selectivity remained stable at 80%. [ABSTRACT FROM AUTHOR]

Manufacturing is fundamental to the real economy. Given the central role of cost management in the manufacturing industry, we study the role of people in firms' cost management. We find that manufacturing background CEOs significantly decrease cost stickiness. The results can be explained by a manufacturing background CEO's focus on corporate cost management and his superior ability to choose flexible production to accelerate inventory flow and mitigate the bullwhip effect. We also show that the impact of manufacturing background CEOs on cost stickiness is more prominent in firms with high demand uncertainty, high economic policy uncertainty, high asset intensity, or low customer concentration. Finally, we report evidence that CEOs with manufacturing and finance backgrounds are associated with less cost stickiness, thus confirming the critical role of business-finance integration in cost management. In sum, these findings highlight the importance of talents in building a powerful manufacturing country. [ABSTRACT FROM AUTHOR]

To improve the flame retardant performance of plywood and reduce the reagent loss and moisture absorption of the flame retardant, a bio‐based supramolecular flame retardant is prepared by vacuum‐pressure impregnation and high‐temperature in situ polymerization in plywood. The best value of bonding strength appears at 170 °C, and the limiting oxygen index (LOI) of 170BF‐B plywood is 42.3%. After hot pressing, the moisture absorption rate of the 170BF‐B veneer is only 18.51%, while the loss resistance rate achieves 83.45%. Its residue at 700 °C is 91.36% higher than that of poplar veneer. In the combustion process, the peak value of heat release rate (PHRR) and heat release rate (HRR) of 170BF‐B plywood are only 10.69% and 37.11% of that of untreated plywood. After combustion, an intumescent flame retardant layer exhibits a graphitization trend. In the flame retardant layer, there are not only functional groups, such as P═O, PO43−, POC decomposed by flame retardant but also characteristic functional groups of wood fiber, like C═O, CH, etc. The prepolymer BF‐B, which is composed of phytic acid, urea, and dicyandiamide polymerized with chitosan or lignocellulose to form a supramolecular flame retardant connected with POC and PON functional groups, thus improving the flame retardant and anti‐loss property by in situ polymerization. [ABSTRACT FROM AUTHOR]

Introduction: Medulloblastoma (MB) is a malignant pediatric brain tumor that arises in the cerebellar granular neurons. Sonic Hedgehog subtype of MB (SHH‐MB) is one of the major subtypes of MB in the clinic. However, the molecular mechanisms underlying MB tumorigenesis are still not fully understood. Aims: Our previous work demonstrated that the receptor for activated C kinase 1 (Rack1) is essential for SHH signaling activation in granule neuron progenitors (GNPs) during cerebellar development. To investigate the potential role of Rack1 in MB development, human MB tissue array and SHH‐MB genetic mouse model were used to study the expression of function of Rack1 in MB pathogenesis. Results: We found that the expression of Rack1 was significantly upregulated in the majority of human cerebellar MB tumors. Genetic ablation of Rack1 expression in SHH‐MB tumor mice could significantly inhibit MB proliferation, reduce the tumor size, and prolong the survival of tumor rescue mice. Interestingly, neither apoptosis nor autophagy levels were affected in Rack1‐deletion rescue mice compared to WT mice, but the expression of Gli1 and HDAC2 was significantly decreased suggesting the inactivation of SHH signaling pathway in rescue mice. Conclusion: Our results demonstrated that Rack1 may serve as a potential candidate for the diagnostic marker and therapeutic target of MB, including SHH‐MB. [ABSTRACT FROM AUTHOR]

Voltage-dependent anion channels (VDACs) are situated in the outer membrane of the mitochondria and serve as gatekeepers that control metabolite and ion exchange between the cytosol and mitochondria. VDAC1 is one of the most studied members of the VDAC protein family and is overexpressed in multiple types of cancer. However, the specific biological function and regulatory mechanism of VDAC1 in breast cancer remains unclear. The present study investigated the biological role of VDAC1 in breast cancer cells using an MTS assay. The association of clinicopathological features with VDAC1 in breast cancer was analyzed by Gene Expression Profiling Interactive Analysis. The regulatory mechanism of VDAC1 was determined by cell transfection, western blot analysis, reverse transcription-quantitative (q)PCR analysis, chromatin immunoprecipitation (ChIP) and ChIP-qPCR analysis. The results of the present study demonstrated that VDAC1 promoted breast cancer proliferation and was associated with a poor prognosis in patients with breast cancer. Additionally, it was observed that the expression of VDAC1 could be decreased by the bromodomain inhibitor (JQ1), and bromodomain-containing protein 4 (BRD4) was indicated to be a regulator of VDAC1. Furthermore, results suggested that VDAC1 may be involved in the resistance of breast cancer to JQ1. Collectively, the present findings uncovered important aspects of the function of VDAC1 in the tumor progression of breast cancer, and may provide a basis for potential therapeutic strategies for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Triglycidylamine (TGA) modified soybean protein isolate (SPI) adhesive can increase the bonding strength of soy protein and improve its utilization. In order to study the chemical changes of TGA modified SPI adhesives during the heating process, the curing mechanism of soybean protein adhesives was studied by Fourier transform infrared (FTIR), second derivative infrared (SDIR) and two-dimensional correlation spectroscopy (2D-COS). With the increase of temperature, there were significant differences in the absorption peaks at 1075 cm−1, 1169 cm−1, 1390 cm−1, 1735 cm−1 indicating the active functional groups bared and reacted in the modified SPI, which formed hydrophobic ester, amide groups. Besides, some functional groups were dismissed or weakened such as N–H and –CH 2 - at 3440 cm−1 and 2847 cm−1 respectively. The epoxy ring of TGA opened to cross-link with the amino and hydroxyl groups within the molecular structure of SPI. The addition of TGA can effectively improve the molecular weight of soybean protein and form a network structure, which provides a method for improving the performance of a soybean protein adhesive. • FTIR, SDIR, 2D-COS characterized the curing process of modified soy protein isolate (SPI) adhesive and pure SPI adhesive during heating process. • 2D-COS synchronous and asynchronous graphs indicated that the epoxy group had underwent a ring opening reaction while the temperature was increasing. • The epoxy group of Triglycidylamine (TGA) underwent dehydration synthesis with functions group exposed in the SPI molecule to form a network macromolecule. • 2D-COS can reflect the sequential relationship of different functional groups in the reaction process. [ABSTRACT FROM AUTHOR]

As thallium (Tl) is a highly toxic heavy metal, there are compulsory environmental regulations in many countries on minimizing its release. This research investigated the treatment of real industrial wastewater with low Tl(I) concentration by Fe0-electrocoagulation (Fe0-EC) in a batch aeration-forced pump cycle reactor. The effects of pH (7–12), current density (8.3–33.3 mA/cm2), dissolved oxygen (DO) in wastewater, and initial Tl(I) concentration (66–165 µg/L) on Tl(I) removal efficiency were investigated. The removal efficiency of Tl(I) is pH-dependent, to be exact, it increases significantly with pH rising from 8 to 11. Initial pH of influent and DO concentration were the key operation parameters which strongly affect Tl(I) removal. After the water sample with initial Tl(I) concentration of 115 µg/L was treated for 12 min by a single-step process at pH of 11 and current density of 16.7 mA/cm2, the residual Tl(I) concentration was decreased to beneath the emission limit in China (2 µg/L) with a low energy consumption of 0.82 kWh/m3. By prolonging the operation time, the concentration was further reduced to 0.5 µg/L or even lower. The main composition of the flocculent sludges is iron oxyhydroxide, yet its crystal structure varies dependent on pH value which may result in different Tl(I) removal efficiency. Feroxyhyte nanosheets generate in situ by Fe0-EC, which contributes to the rapid and effective removal of Tl(I), while the speedy oxidation under DO-enriched conditions benefits the feroxyhyte formation. The mechanism of Tl(I) removal by Fe0-EC is attributed to the combination of electrostatic attraction and the formation of inner-sphere complexes. As shown in the technical and mechanical studies, Fe0-EC technology is an effective method for low Tl concentration removal from wastewater. [ABSTRACT FROM AUTHOR]

We obtained the chemical abundances of more than 20 Barium (Ba) stars by analysing high resolution echelle spectra. They show obvious overabundances of neutron capture process elements, such as Y, Zr, Ba, La and Eu. Their abundance pattern can be explained by binary accretion through stellar wind, where the Ba stars have accreted the ejecta from the companion stars which were in AGB stages at that time and now evolve as white dwarfs. [ABSTRACT FROM PUBLISHER]

• PA-Fe chelate forms a flame-retardant layer with a high degree of graphitization. • Fe 2 O 3 can effectively catalyze the conversion of unsaturated gases. • The crosslinking reaction between PA and TDI enhances the mechanics of MPCs. The applicability of wood-plastic composites has attracted great attention due to the improved sustainability. However, the fabrication of wood-plastic composites with excellent flame retardance and smoke suppression without compromising the mechanical property remains a great challenge. In this study, marigold straw (MS)-polyurethane (PU) composites (MPCs) were treated with phytic acid (PA) as a flame retardant and iron oxide (Fe 2 O 3) as a smoke suppressor. The oxygen index of the proposed Fe/TMS (treated marigold straw)/PU/PA-10 composite was 27.8, and the total heat release was 12.02 MJ/m2. Fe 2 O 3 and PA formed a mesh chelate in the form of a coordination bond, which provided a highly graphitized solid flame-retardant layer during the combustion process, improving the high-temperature stability of Fe/TMS/PU/PA-10. In addition, Fe 2 O 3 can effectively catalyze the conversion of unsaturated gases, such as CO, into CO 2. This is essential to suppress the smoke release and also avoid the production of toxic gases. The phosphate group of PA is cross-linked with the -NCO group of TDI (2,4-Toluene diisocyanate), thus significantly enhanced the physical properties of MPCs. This study provides an environmentally friendly approach to enhancing the flame retardancy and smoke suppression of MPCs. [Display omitted] [ABSTRACT FROM AUTHOR]

Spliceosomal GTPase elongation factor Tu GTP binding domain containing 2 (EFTUD2) is a causative gene for mandibulofacial dysostosis with microcephaly (MFDM) syndrome comprising cerebellar hypoplasia and motor dysfunction. How EFTUD2 deficiency contributes to these symptoms remains elusive. Here, we demonstrate that specific ablation of Eftud2 in cerebellar Purkinje cells (PCs) in mice results in severe ferroptosis, PC degeneration, dyskinesia, and cerebellar atrophy, which recapitulates phenotypes observed in patients with MFDM. Mechanistically, Eftud2 promotes Scd1 and Gch1 expression, upregulates monounsaturated fatty acid phospholipids, and enhances antioxidant activity, thereby suppressing PC ferroptosis. Importantly, we identified transcription factor Atf4 as a downstream target to regulate anti-ferroptosis effects in PCs in a p53-independent manner. Inhibiting ferroptosis efficiently rescued cerebellar deficits in Eftud2 cKO mice. Our data reveal an important role of Eftud2 in maintaining PC survival, showing that pharmacologically or genetically inhibiting ferroptosis may be a promising therapeutic strategy for EFTUD2 deficiency-induced disorders., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)