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This paper reports the discovery of a magnetophotoluminescence response in metallofullerene Y3N@C80 triggered by the triplet excited state. In experiments, Y3N@C80 exhibits magnetic field‐dependent (0→±42 T) phosphorescence emission at 4.2 K. Crucially, with increasing magnetic field, the phosphorescence peaks shift to longer wavelengths owing to the Zeeman effect. Further, a nanoring of [9]CPPH is employed to modulate the magnetophotoluminescence response of Y3N@C80 through host−guest interaction. The circularly polarized phosphorescence spectra of Y3N@C80 and Y3N@C80⊂[9]CPPH are investigated to further reveal their magnetophotoluminescence properties using the technique of field‐induced circular polarization (FICPO). These results show that metallofullerene Y3N@C80 with magnetophotoluminescence response has potential applications in spin‐related optical devices and quantum technology. [ABSTRACT FROM AUTHOR]

Lactic acid is an important organic acid with wide applications, and preparation of lactic acid from biomass-derived 1,2-propanediol was considered a green reaction route. In this paper, a Cu modified Au/γ-Al2O3 catalyst was designed for the oxidative esterification of 1,2-propanediol to methyl lactate in an alkali-free methanol system. The structural properties of the Au–Cu/γ-Al2O3 catalyst were characterized by various characterization methods, and interaction between Au nanoparticles and Cu species was discovered. Moreover, the catalytic tests showed that the Cu modified Au/γ-Al2O3 catalysts exhibited higher methyl lactate selectivity than the monometallic Au/γ-Al2O3 catalyst. It was revealed that the synergistic effect between the Au nanoparticles and Cu species could promote the oxidation of primary hydroxyl groups of 1,2-propanediol to produce methyl lactate and reduce the generation of by-products. In addition, a reasonable reaction pathway for the oxidative esterification of 1,2-propanediol was proposed based on the comparative experiments. These findings may provide favorable guidance for design of Au based nanocatalysts for the oxidative esterification of alcohols to esters and carboxylic acids. [ABSTRACT FROM AUTHOR]

Cyclohexane epoxide, which contains highly active epoxy groups, plays a crucial role as an intermediate in the preparation of fine chemicals. However, controlling the epoxidation pathway of cyclohexene is challenging due to issues such as the allylic oxidation of cyclohexene and the ring opening of cyclohexane epoxide during the cyclohexene epoxidation process to form cyclohexane oxide. This review focuses on the structure‐activity relationships and synthesis processes of various heterogeneous transition metal‐based catalysts used in cyclohexene epoxidation reactions, including molybdenum(Mo)‐based, tungsten(W)‐based, vanadium(V)‐based, titanium(Ti)‐based, cobalt(Co)‐based, and other catalysts. Initially, the mechanism of cyclohexene epoxidation by transition metal‐based catalysts is examined from the perspective of catalytic active centers. Subsequently, the current research of cyclohexene epoxidation catalysts is summarized based on the perspective of catalyst support. Additionally, the differences between alkyl hydroperoxide, hydrogen peroxide (H2O2), and oxygen (O2) as oxidants are analyzed. Finally, the main factors influencing catalytic performance are summarized, and reasonable suggestions for catalyst design are proposed. This work provides scientific support for the advancement of the olefin epoxidation industry. [ABSTRACT FROM AUTHOR]

Oceanic general circulation models (OGCMs) are important tools used to investigate mechanisms for ocean climate variability and predict the ocean change in the future. However, in most current ocean models, the impact of sea surface waves as one of the most significant dynamic processes in the upper ocean is absent. In this study, the Stokes drift and the vertical mixing induced by nonbreaking surface waves derived from the wave model (WAVEWATCH III) are incorporated into a Climate System Ocean Model, and their effects on an ocean climate simulation are analyzed. Numerical experiments show that both physical processes can improve the simulation of sea surface temperature (SST) and mixed layer depth (MLD) in the Southern Hemisphere. The introduction of Stokes drift effectively reduces the subsurface warm bias in the equatorial tropics, which is caused by the weakening of vertical mixing in the equatorial region. The nonbreaking surface wave mainly reduces the temperature bias in the Southern Ocean by enhancing mixing in the upper ocean. For the MLD, the Stokes drift mainly improves the simulation of the winter MLD, and the nonbreaking surface wave improves the summer MLD. For MLD south of 40° S in summer, the introduction of nonbreaking surface waves resulted in a reduction of 11.86 m in MLD bias and 7.8 m in root mean square errors (RMSEs), respectively. For winter subtropical MLD in the Southern Hemisphere, considering the Stokes drift, the MLD bias and RMSEs were reduced by 2.49 and 5.39 m, respectively. Adding these two physical processes simultaneously provides the best simulation performance for the structure of the upper layer. The introduction of sea surface waves effectively modulates the vertical mixing of the upper ocean and then improves the simulation of the MLD. Thus, sea surface waves are very important for ocean simulation, so we will further couple a sea waves model in the Chinese Academy of Sciences Earth System Model (CAS-ESM) as part of their default model component. [ABSTRACT FROM AUTHOR]

Furfural is one of the most important biomass platform compounds and can be used to prepare various high-value-added chemicals. The reactions of furfural with aliphatic alcohols via an oxidative esterification reaction or oxidative condensation reaction can bond two carbon molecules together and produce longer hydrocarbon chains chemicals, including methylfuroate and some low-volatility liquid biomass fuels. Thus, these reactions are considered significant utilization routes of furfural, and many inspiring catalytic systems have been designed to promoted these reactions. In this work, the reported catalytic systems for the oxidative esterification and oxidative condensation reactions are reviewed separately. The catalysts for the oxidative esterification reaction are reviewed for the classification of noble metal catalysts and non-noble metal catalysts, according to the active metals in the catalysts. For the oxidative condensation reactions, the studies using oxygen as the oxidant are reviewed firstly, and then the studies conducted using the hydrogen transfer process are analyzed subsequently. Furthermore, suggestions for future research directions for the oxidative esterification and oxidative condensation reactions are put forward. [ABSTRACT FROM AUTHOR]

Palladium (Pd) nanostructures are highly active non-platinum anodic electrocatalysts in alkaline direct methanol fuel cells (DMFCs), and their electrocatalytic performance relies highly on their morphology and composition. This study reports the preparation, characterizations, and electrocatalytic properties of palladium-copper alloys loaded on the carbon support. XC-72 was used as a support, and hydrazine hydrate served as a reducing agent. PdxCuy/XC-72 nanoalloy catalysts were prepared in a one-step chemical reduction process with different ratios of Pd and Cu. A range of analytical techniques was used to characterize the microstructure and electronic properties of the catalysts, including transmission electron microscopy (TEM), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma emission spectroscopy (ICP-OES). Benefiting from excellent electronic structure, Pd3Cu2/XC-72 achieves higher mass activity enhancement and improves durability for MOR. Considering the simple synthesis, excellent activity, and long-term stability, PdxCuy/XC-72 anodic electrocatalysts will be highly promising in alkaline DMFCs. [ABSTRACT FROM AUTHOR]

TiO2 photocatalysis, as an energy‐saving, high‐efficiency and green technology, has a wide range of applications in sewage treatment, cancer treatment, hydrogen production, photocatalytic CO2 reduction and photocatalytic sensors. However, the large band width (Eg=3.2 eV) of TiO2 material hinders its practical application, which in turn leads to low visible‐light utilization and low quantum yield. Therefore, the preparation of TiO2 with high quantum yield and fast response to visible light has become a key topic in current photocatalyst research. This review discusses different photocatalytic applications, current synthetic techniques for the elaboration of nanostructures of several TiO2‐based materials and recent advances in enhancing visible photocatalytic activity. [ABSTRACT FROM AUTHOR]

A series of NiAlO composite oxide catalysts with high surface areas and high Ni dispersion were prepared through an improved co-precipitation method. The new preparation method effectively improved the specific surface area and pore volume of the catalyst, promoted the dispersion of nickel species, alleviated the agglomeration of the catalyst, and improved the stability of the catalyst by strengthening the interaction between Ni and Al. The typical catalyst Ni20Al had a specific surface area of 359 m2/g and a NiAl2O4 phase. In the dehydrogenation of methylcyclohexane over the Ni20Al catalyst, the conversion of methylcyclohexane could reach 77.4%, with toluene selectivity of 85.6%, and a hydrogen release rate of 63.94 mmol g−1 h−1, and did not show any significant inactivation during the stability test over 29 h under the reaction conditions of reaction temperature 450 °C and LHSV = 4 mL g−1 h−1. However, the conversion of methylcyclohexane with the IM-NiAl catalyst prepared through the traditional impregnation method was only 50.75%, with toluene selectivity of 70.5%, and with a hydrogen release rate of 35.84 mmol g−1 h−1, and the lifetime of the catalyst was only 15 h. [ABSTRACT FROM AUTHOR]

In this paper, we propose a knowledge sharing oriented approach to enable a robot to reuse other robots' knowledge by adapting itself to the inverse dynamics model of the knowledge-sharing robot. The purpose of this work is to remove the heavy fine-tuning procedure required before using a new robot for a task via reusing other robots' knowledge. We use the Neural Knowledge DNA (NK-DNA) to help robots gain empirical knowledge and introduce a Knowledge Adaption Module (KAM) utilizing the deep neural networks (DNN) for knowledge reuse. The initial experiment shows that the target robot can adapt to the inverse dynamic model of the source robot via our KAM and reuse the knowledge shared by the source robot. [ABSTRACT FROM AUTHOR]

High-efficiency production of xylene/trimethylbenzene from benzene/toluene with methanol is a potential way to promote the implementation on the coupled cycle development strategy of petrochemical and coal chemical industry and optimize the resource structure. At the same time, relying on the innovation of catalytic new materials, physical chemistry, intelligent capture technology, process engineering, and other principles and methods, p-xylene (PX) and trimethylbenzene (TMB) with higher added value were prepared by C6-8~arene methylation, which could elevate the level of methylation field and improve the competitiveness of the industry. This paper focuses on the one-step methylation reaction of benzene with methanol or toluene with methanol to obtain high-purity p-xylene (BM-PX/TM-PX), and the one-step methylation reaction of xylene with methanol to obtain mesitylene (XM-TMB). The methylation reaction mechanism and the preparation strategy of a high-performance catalyst were reviewed. The high selectivity of PX obtained by precisely controlling the pore size and acid site distribution of zeolites was emphasized. Meanwhile, the current research progress of TMB, the kinetic/thermodynamics of the BM-PX/TM-PX, and XM-TMB methylation reaction were described. Based on a literature research and the conclusion of our research group, the mechanism of methylation reaction process was expounded. Finally, the new research direction of catalysts used and reaction process in methylation reaction were prospected in order to guide the rapid development of this field. [ABSTRACT FROM AUTHOR]

Luminescent thermometers provide a non-contact method of probing temperature with high sensitivity and response speed at the nanoscale. Synergistic photoluminescence from different activators can realize high sensitivity for luminescent thermometers by finely selecting ions with specific crystallographic sites. Herein, the more temperature-sensitive Mn4+ and the less-sensitive Eu3+ (or Sm3+) activators are co-doped into a Ca2GdSbO6 matrix to form an effective thermometer, where Mn4+ and Eu3+ (or Sm3+) ions occupy the Sb5+ and Gd3+ sites, respectively. The co-doping of Eu3+ ions or Sm3+ ions leads to lattice expansion of Ca2GdSbO6 matrix and a tuned narrow emission from deep-red to orangish-red. According to the ratio of luminescence intensity, the maximal Sa and Sr values are 0.19 K−0 (347 K) and 1.38% K−( (420 K) for Ca2GdSbO6:Mn4+/Eu3+ probe and 0.26 K−p (363 K) and 1.55% K−( (430 K) for Ca2GdSbO6:Mn4+/Sm3+ probe thermometers, respectively. In addition, thermometers based on Mn4+ emission lifetimes can provide the highest relative sensitivity of 1.47% K−s at 425 K. Thus, the highly-temperature-sensitive Ca2GdSbO6:Mn4+/(Eu3+ or Sm3+) phosphor is a promising candidate for practical luminescence thermometers. [ABSTRACT FROM AUTHOR]

Porous bimetallic TiO 2 –Fe 2 O 3 composite nanofibers with different Fe 2 O 3 compositions (0–40 wt%) were prepared via a simple one-pot electrospinning approach. The surface areas, pore diameters, crystallinity and mesostructures of the bimetallic nanofibers were reasonably tuned by changing the Fe 2 O 3 compositions. A feasible mechanism of TiO 2 nanofiber modified with Fe 2 O 3 was proposed. The sensing results showed that TiO 2 –Fe 2 O 3 nanofibers with an appropriate Ti/Fe ratio exhibited much better Fenton activity than pure TiO 2 nanofibers. The best Fenton properties of methylene blue (MB) degradation were found for 60 wt% TiO 2 -40 wt% Fe 2 O 3 nanofibers, which formed a progressive TiO 2 /Fe 3 Ti 3 O 10 /Fe 2 O 3 triple-heterojunction and accelerated charge transfer and Fe3+/Fe2+ cycle reaction efficiency. More active sites were responsible for the high activity in the Fenton reaction. Porous bimetallic TiO 2 –Fe 2 O 3 composite nanofibers with different Ti/Fe ratio were prepared via a simple one-pot electrospinning approach. Pure nano-TiO 2 fiber had the smallest diameter but the largest particle size. Hence, it possessed a very low surface area because the large grains had to be confined to such a narrow range in fiber by compact and repetitive particle accumulation. TiO 2 fibers exhibited a good methylene blue (MB) degradation rate, which also indicated that TiO 2 itself can provide certain active sites. Thereafter, adding Fe 2 O 3 to TiO 2 can effectively adjust its structure and catalytic performance. When the doping amount of Fe 2 O 3 was 15%, the nanofiber diameter increased, and the particle size of TiO 2 decreased. The wide space can make TiO 2 particles uniformly dispersed, and there are many gaps among the grains. It can be seen from XRD and TEM that the TiO 2 particles were even dispersed, and Fe 2 O 3 particles were so small and homogeneous that they went undetected in XRD. These factors contributed to the rapid increase in its specific surface area. However, the Fenton activity decreased, probably due to too few Fe 2 O 3 active sites, the strong binding force between TiO 2 and Fe 2 O 3 to reduce the lattice oxygen mobility and prejudice redox reactions on the catalyst surface, and the active sites of TiO 2 were overlaid and passivated by Fe 2 O 3. As the iron content continued to increase to 40%, the fiber diameter decreased, and TiO 2 grains increased. The gradually enlarged grains were astricted by the fiber with reduced diameter, the dispersion of Ti–Fe particles was bound to slightly decrease compared with 85 wt%TiO 2 –15 wt%Fe 2 O 3 , the BET of bimetallic composite dropped but was larger than that of pure TiO 2 and mapping showed various elements still were evenly dispersed on the fiber. TiO 2 may be activated on the basis of H 2 -TPR results (reduction peak about pure TiO 2 was observed 580 °C, whereas reduction peak approximately 60 wt%TiO 2 –40 wt%Fe 2 O 3 was observed 515 °C, respectively.). XRD and TEM demonstrated that a new crystal phase Fe 3 Ti 3 O 10 appeared. It was believed that 60 wt%TiO 2 –40 wt%Fe 2 O 3 formed a progressive TiO 2 /Fe 3 Ti 3 O 10 /Fe 2 O 3 triple heterojunction, which accelerated the charge transfer and Fe3+/Fe2+ cycle reaction efficiency on surface of the catalyst, leading to a higher activity. [Display omitted] • TiO 2 -Fe 2 O 3 composite nanofibers (CNs) were synthesized by an electrospinning process. • The surface areas, fiber diameters and crystallinity of the TiO 2 -Fe 2 O 3 CNs are controlled by changing the iron content. • The CNs with appropriate Ti/Fe ratio exhibited a higher BET and much better Fenton activity than pure TiO 2. • The feasible mechanism of TiO 2 nano-fibers modified with Fe 2 O 3 was proposed. [ABSTRACT FROM AUTHOR]

Although HZSM-5 zeolite is more and more widely used in petrochemical industry and other fields, its single narrow micropore system often leads to mass transfer issues during some types of catalytic reactions. In addition, dealumination in the presence of steam and coking due to the presence of strong acids sites are issues of aluminosilicate catalysts in general. In this work, a simple post-treatment method based on the traditional prepared HZSM-5 catalyst was proposed and an outlayer SiO 2 encapsulated Gd/HZSM-5 catalyst with hollow and hierarchical porous systems (Si@Gd/Z5-T) was obtained. This catalyst can overcome those defects for the traditional HZSM-5 mentioned above, such as, the outermost SiO 2 layer can protect the aluminum species in the framework of Gd/HZSM-5 and cover part of strong acid sites, and the hollow and hierarchical porous systems can minimize the mass transfer resistance, etc. The Si@Gd/Z5-T catalyst exhibited high selectivity of BTX (65.7%), especially xylene (39.7%), in the methanol to aromatics reaction (MTA) owing to the suitable acidity and optimized porous system. In addition, the Si@Gd/Z5-T catalyst possessed much better hydrothermal stability and the excellent anticoking ability in the MTA reaction as expected. Thus, this should be a general method for the modification of silica alumina molecular sieve catalysts to obtain the novel catalyst with hollow and hierarchical porous systems, adjustable acidity and high hydrothermal stability. An outlayer SiO 2 encapsulated Gd/HZSM-5 catalyst with hollow and hierarchical porous systems (Si@Gd/Z5-T) was prepared through a simple post-treatment method, which exhibited the high selectivity of BTX (65.7%) especially xylene (39.7%) in the methanol to aromatics reaction. [Display omitted] • An outlayer SiO 2 encapsulated Gd/HZSM-5 with hollow structure was prepared. • This catalyst can overcome the defects for the traditional HZSM-5 catalyst. • The catalyst exhibited high selectivity of BTX (65.7%) in the MTA reaction. • The catalyst possessed excellent hydrothermal stability and anticoking ability. [ABSTRACT FROM AUTHOR]

The FeAPO-44 molecular sieve with CHA-type structure has been synthesized under solvent-free conditions. This is the first case that this material was successfully prepared by this novel solvent-free method. Its optimal synthesis conditions were refined. The results show that proper P 2 O 5 /Al 2 O 3 ratio, a lower SDA/Al 2 O 3 ratio (SDA: cyclohexylamine) and relatively mild crystallization temperature are more beneficial to the synthesis of pure CHA phase. The structural and compositional characteristics of the relatively pure FeAPO-44 zeolite were studied in depth by XRD, TG-DSC, CHN element analysis, EDS, SEM and N 2 physisorption. According to the CHN element analysis, EDS and TG-DSC measurements, the approximate chemical formula of the synthesized sample SDA/Al-1.4 was determined. The catalytic performances of selected samples were investigated in the methanol-to-olefins reaction. The present results imply that many other zeolite topologies may be conveniently prepared by this solvent-free route. [Display omitted] • FeAPO-44 molecular sieve with CHA topology was firstly prepared by a novel solvent-free method. • The ideal chemical composition of the FeAPO-44 molecular sieve was determined. • A facile preparation procedure was developed to synthesize CHA-type material. [ABSTRACT FROM AUTHOR]

Anchoring Pt onto multi-heteroatom doped carbon materials has been recognized as an effective approach to improve the performance of electrocatalytic methanol oxidation. However, distinct contributions and specific behavior mechanisms of different heteroatoms, notably N and P, the specific behavior mechanisms in synergistically promoting Pt NPs remain elusive. In this work, we construct 1D N and P co-doped carbon nanotube (N, P-CNTs) supports with abundant defect anchors for Pt. The as-prepared Pt/N, P-CNTs exhibit outstanding activity and exceptional stability in methanol oxidation reaction (MOR), achieving high mass activity up to 6481.3 mA mg -1 Pt . Moreover, they can retain 90.5 % of their initial current density even after 800 cycles tests. Detailed characterizations and theoretical calculations indicate that the robust strong metal-support interactions (SMSI) effect caused by N doping within the unique N and P co-doped coordination structure controllably regulate the coordination environment of Pt, reduce the d-band center of Pt, thus promoting the adsorption and decomposition of CH 3 OH. However, P doping weakens the adsorption strength of CO on the Pt active site by sacrificing partial electron transfer, accelerating the oxidative conversion of the CO-like poisoning species (CO ads ). Significantly, the synergistic mechanism of N and P species on the modification of Pt's electronic structure and its subsequent impact on the electrocatalytic methanol oxidation behaviors on the Pt surface was thoroughly elucidated, providing a constructive route for designing robust MOR electrocatalysts with high MOR activity and durability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

TiO 2 photocatalysis, as an energy-saving, high-efficiency and green technology, has a wide range of applications in sewage treatment, cancer treatment, hydrogen production, photocatalytic CO 2 reduction and photocatalytic sensors. However, the large band width (E g =3.2 eV) of TiO 2 material hinders its practical application, which in turn leads to low visible-light utilization and low quantum yield. Therefore, the preparation of TiO 2 with high quantum yield and fast response to visible light has become a key topic in current photocatalyst research. This review discusses different photocatalytic applications, current synthetic techniques for the elaboration of nanostructures of several TiO 2 -based materials and recent advances in enhancing visible photocatalytic activity., (© 2022 Wiley-VCH GmbH.)

To enhance nanocatalyst performance and durability for the methanol oxidation reaction (MOR) in a direct methanol fuel cell, small-sized (2.1 nm) and structurally ordered Pt 3 Co intermetallic nanoparticles are uniformly anchored onto nitrogen-doped carbon nanotubes (N-CNTs) via a low-temperature N-anchoring method, and the N-doping abilities of different N-containing reagents are compared. After investigating the microstructure of Pt 3 Co/N-CNTs and evaluating their catalytic activity for the MOR, the results show that N-doping facilitates the uniform loading of Pt 3 Co NPs and plays a crucial role in improving the electrocatalytic activity of Pt 3 Co NPs supported on CNTs. Pt 3 Co/N-CNT-M with melamine as the N dopant exhibits the highest MOR activity and stability among all N-CNT-supported Pt 3 Co NPs and Pt/N-CNT-M. Density functional theory calculations suggest that the doping of N enhances the binding energy of CNTs to Pt 3 Co NPs, and the MOR mechanism shows that the introduction of Co is the reason for the enhancement of MOR reaction kinetics. The excellent electrochemical performance of Pt 3 Co/N-CNT-M is mainly attributed to the synergistic effect of N and Pt 3 Co intermetallic nanoparticles. The combination of ordered alloy nanoparticles and high-performance carrier N-CNT-M described herein exhibits great potential for fuel cells and may provide an unequivocal direction for the optimization of catalyst performance.

Luminescent thermometers provide a non-contact method of probing temperature with high sensitivity and response speed at the nanoscale. Synergistic photoluminescence from different activators can realize high sensitivity for luminescent thermometers by finely selecting ions with specific crystallographic sites. Herein, the more temperature-sensitive Mn 4+ and the less-sensitive Eu 3+ (or Sm 3+ ) activators are co-doped into a Ca 2 GdSbO 6 matrix to form an effective thermometer, where Mn 4+ and Eu 3+ (or Sm 3+ ) ions occupy the Sb 5+ and Gd 3+ sites, respectively. The co-doping of Eu 3+ ions or Sm 3+ ions leads to lattice expansion of Ca 2 GdSbO 6 matrix and a tuned narrow emission from deep-red to orangish-red. According to the ratio of luminescence intensity, the maximal S a and S r values are 0.19 K -0 (347 K) and 1.38% K -( (420 K) for Ca 2 GdSbO 6 :Mn 4+ /Eu 3+ probe and 0.26 K -p (363 K) and 1.55% K -( (430 K) for Ca 2 GdSbO 6 :Mn 4+ /Sm 3+ probe thermometers, respectively. In addition, thermometers based on Mn 4+ emission lifetimes can provide the highest relative sensitivity of 1.47% K -s at 425 K. Thus, the highly-temperature-sensitive Ca 2 GdSbO 6 :Mn 4+ /(Eu 3+ or Sm 3+ ) phosphor is a promising candidate for practical luminescence thermometers.

The screening of high-efficiency and low-energy consumption absorbents is critical for capturing SO 2 . In this study, absorbents with better performance are screened based on mechanism, model, calculation, verification, and analysis methods. The acidity coefficient (p K a ) values of ethylenediamine (EDA), piperazine (PZ), 1-(2-hydroxyethyl)piperazine (HEP), 1,4-bis(2-hydroxyethyl)piperazine (DIHEP), and 1-(2-hydroxyethyl)-4-(2-hydroxypropyl)piperazine (HEHPP) are calculated by quantum chemical methods. A mathematical model of the SO 2 cyclic absorption capacity per amine (α c ) in the amine-based SO 2 capture process is built based on the electroneutrality of the solution. Another model of desorption reaction heat ( Q des ) is also built based on the van't Hoff equation. Correspondingly, α c and Q des of the above five diamines are calculated and verified with the experimental data. The results show that α c of the diamine changes with the increase in the p K a value, and the increase in the p K a value directly leads to changes in Q des . The order of α c of the above five diamines is EDA > PZ > HEHPP > HEP > DIHEP, and the order of Q des is EDA > PZ > HEHPP > DIHEP > HEP. The multiobjective analysis between α c and Q des suggests that it is not advisable to simply pursue a higher α c while ignoring Q des . The compound quaternary system absorbent has a wider range of α c than the single ternary absorbent, which is the direction of absorbent development. This study is expected to strengthen absorbent screening for the amine-based SO 2 capture process from flue gas., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Toluene methylation using methanol offers a high potential molecular engineering process to produce p -xylene (PX) based on shape-selective catalysts. To further improve the process economics, a novel short process was proposed by reducing the high-energy consumption separation of xylene isomers in existing processes since the PX selectivity of the xylene isomers can be enhanced more than the industrial product quality of 99.7%. The PX selectivity intensification was achieved as a result of decreased contact time by considering factors such as the feed ratio, diluents, temperature, and pressure in a toluene methylation reactor. This proposed short process indicated that the reactor effluent could be purified only through the two conventional distillation towers by removing the methanol recovery and separation of xylene isomers. The raw material utilization, energy consumption, and economic data were also analyzed for the six contrastive cases. The short process using catalyst Si-Mg-P-La/ZSM-5 exhibited the highest effective utilization rates of 96.27 and 95.50% for toluene and methanol, respectively. The short process also showed a good economic value in terms of capital investment and operating costs due to the multistage reactor without benzene byproducts. Thus, the obtained total annual cost (TAC) value of 13 848.1 k$·year -1 was 68.9 and 87.9% of the two existing processes., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Modulating the crystal field environment around the emitting ions is an effective strategy to improve the luminescence performance of the practical effective phosphor materials. Here, smaller Y 3+ ions are introduced into substituting the Gd 3+ sites in Ba 2 GdNbO 6 :Mn 4+ phosphor to modify the optical properties, including the enhanced luminescence intensity, redshift, and longer lifetime of the Mn 4+ ions. The substitution of smaller Y 3+ ions leads to lattice contraction and then strengthens pressure on the local structure, enhances lattice rigidity, and suppresses nonradiative transition. Moreover, the prototype phosphor-converted light-emitting diode (LED) demonstrates a continuous change photoelectric performance with a correlated color temperature of 4883-7876 K and a color rendering index of 64.1-83.2, suggesting that it can be one of the most prospective fluorescent materials applied as a warm red component for white LEDss. Thus, the smaller ion partial substitution can provide a concise approach to modulate the crystal field environment around the emitting ions for excellent luminescence properties of phosphors toward the modern artificial light.