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While blending with flexible polymers has been a commonly employed strategy to enhance the toughness of polylactic acid (PLA), it's still a great challenge to avoid the sacrifice of tensile strength at the same time. In this work, we demonstrate a promising route to simultaneously improve the strength and toughness of PLA by compounding PLA with poly(ε‐caprolactone) (PCL) and PLA grafted multi‐walled carbon nanotubes core‐shell nanofiller (MWNT‐PCLPLA) via a two‐step ring‐opening polymerization and have analyzed the strengthening and toughening mechanism through molecular dynamics simulation. The double polymer layers of MWNT‐PCLPLA effectively improve the interfacial interaction between MWNTs and the matrix, in which the outer PLA layer has the same molecular structure with the matrix and facilitates stress transfer, while the flexible PCL layer can absorb energy through self‐deformation and induce local plastic deformation of the matrix. When the content of MWNTs was only 1 wt%, the strength and elongation at break of PLA/MWNT‐PCLPLA nanocomposites were increased by 47.92% and 690.11% compared to neat PLA. Furthermore, the toughness of nanocomposites reached 11.93 MJ/m3, which is about 16 times that of neat PLA. This novel core‐shell nanofiller with double polymer layers is expected to be further applied in other polymer systems. Highlights: A core‐shell nanofiller with double polymer layers was synthesized.Improved dispersion and interfacial compatibility of nanofillers in matrix.The crystallization ability of PLA was improved by functionalized MWNTs.Simultaneously improved strength and toughness of PLA/MWNT‐PCLPLA nanocomposite. [ABSTRACT FROM AUTHOR]

Two new heteroleptic indium aminothiolate compounds [InClSC2H4N(Me)SC2H4]3[1] and [InSC2H4N(Me)SC2H4(C8H5F3NO)] [2] were synthesized by in situ salt metathesis reaction involving indium trichloride, aminothiol, and N,O-β-heteroarylalkenol ligands. The complexes were subsequently purified and thoroughly characterized by nuclear magnetic resonance (NMR) analysis, elemental studies, mass spectroscopy, and X-ray diffraction single crystal analysis that showed a trigonal bipyramidal coordination of In(III) in both complexes. Thermogravimetric analysis of [1] revealed a multistep decomposition pathway and the formation of In2S3 at 350 °C, which differed from the pattern of [2] due to the lower thermal stability of [1]. Compound [2] exhibited a three-step decomposition process, resulting in the formation of In2S3 at 300 °C. The Chemical Vapor Deposition (CVD) experiment involving compound [2] was conducted on the FTO substrate, resulting in the production of singular-phase In2S3 deposits. A comprehensive characterization of these deposits, including crystal structure analysis via X-ray diffraction (XRD), and surface topography examination through scanning electron microscopy (SEM) has been completed. The presence of In–S units was also supported by the Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and energy dispersive spectroscopy (EDS) of the as-deposited films. Moreover, the electronic structure and thermal properties of compound [2] were investigated through DFT calculations. Electron density localization analysis revealed that the highest occupied molecular orbital (HOMO) exhibited dense concentration at the aminothiolate moiety of the complex, while the lowest unoccupied molecular orbital (LUMO) predominantly resided at the N,O-β-heteroarylalkenolate ligand. Furthermore, our computational investigation has validated the formation of indium sulfide by elucidating an intermediate state, effectively identified through EI-MS analysis, as one of the plausible pathways for obtaining In2S3. This intermediate state comprises the aminothiolate ligand (LNS) coordinated with indium metal. [ABSTRACT FROM AUTHOR]

The traditional rule-based energy management strategy for plug-in hybrid vehicles has issues, such as difficulty in online correction and limited online optimization capabilities. In addition, the global optimization energy management strategy cannot be applied online or in real-time. Considering the above difficulties, this study proposes a real-time optimization energy management strategy based on the Markov chain for driving condition prediction and online optimization with the minimum principle. To verify the proposed control strategy, the plug-in hybrid vehicle dynamics model, driving condition prediction model, and online optimization control model were first established. The initial value of the battery state of charge was set to 0.4 under the UDDS (Urban Dynamometer Driving Schedule) standard cycle. The simulation results showed that the comprehensive fuel consumption cost was 1.66 yuan, which was 8.28% better than the energy economy of the traditional rule-based energy management strategy. At the same time, a complete vehicle test was also conducted based on a sample vehicle test platform. The experimental results indicated that the energy management strategy proposed herein exhibits better fuel economy compared to that exhibited by the traditional rule-based energy management strategy. Simulations and experiments have verified the effectiveness of the proposed control strategy in this study. [ABSTRACT FROM AUTHOR]

The traditional rule-based energy management strategy for plug-in hybrid vehicles has issues, such as difficulty in online correction and limited online optimization capabilities. In addition, the global optimization energy management strategy cannot be applied online or in real-time. Considering the above difficulties, this study proposes a real-time optimization energy management strategy based on the Markov chain for driving condition prediction and online optimization with the minimum principle. To verify the proposed control strategy, the plug-in hybrid vehicle dynamics model, driving condition prediction model, and online optimization control model were first established. The initial value of the battery state of charge was set to 0.4 under the UDDS (Urban Dynamometer Driving Schedule) standard cycle. The simulation results showed that the comprehensive fuel consumption cost was 1.66 yuan, which was 8.28% better than the energy economy of the traditional rule-based energy management strategy. At the same time, a complete vehicle test was also conducted based on a sample vehicle test platform. The experimental results indicated that the energy management strategy proposed herein exhibits better fuel economy compared to that exhibited by the traditional rule-based energy management strategy. Simulations and experiments have verified the effectiveness of the proposed control strategy in this study. [ABSTRACT FROM AUTHOR]

It is of supreme importance to develop recyclable and green heterogeneous catalysts due to their potential to reduce environmental impact and reduce costs associated with their use. Hence, in this research, an initial development was made of a core–shell magnetic structure composed of Fe3O4 and a microporous organic network (MON), followed by the physical absorption of palladium nanoparticles (NPs) onto the outer surface of this shell substance. The results of TEM and EDX analyses indicated that Pd NPs of varying sizes, which were produced by using different reducing agents, were evenly bound to the MON shell materials. The use of PiFM and XPS analyses provided evidence that there was effective bonding between Pd nanoparticles and the amine groups present on the surface of MON materials. Besides, the successful immobilization of palladium NPs was also approved by N2 adsorption/desorption analyses with the decrease of the surface from 328 to 227 m2/g after palladium inclusion. The prepared nanoheterogeneous catalysts can catalyze the C–C formation in mild conditions, green solvents, and short reaction times with good to excellent yields. The results revealed that the catalyst with smaller palladium NPs sized 1–5 nm and in medium abundance has better catalytic performance toward C–C formation, compared to those with bigger Pd NPs sized 5–15 nm and in both low and high Pd contents. [ABSTRACT FROM AUTHOR]

This study aims to determine the sources of indoor particulate matter at the Potala Palace Museum in Tibet, China, and evaluate the potential hazards of these pollutants for cultural relics. Long-term monitoring of indoor and outdoor suspended particulate matter concentrations was conducted, and sediment particle samples were collected. The chemical composition of the deposited particles was determined using X-ray fluorescence analysis (XRF). The outdoor suspended particulate concentration was much lower than that indoors; the indoor PM1-10 concentration was much higher than that outdoors and was less affected by outdoor sources. The sources of indoor deposited particles in the high-plateau museum can be classified into four categories: soil dust brought in by tourists from the outdoors, incense ash, pollution from human activities, and ores. Based on data analysis and discussion, proper ventilation can dilute indoor suspended particulate matter, and the installation of air conditioning systems can control temperature and humidity at 20 °C and about 45–60%, respectively, and reduce the fluctuation value, so as to promote particle deposition and better protect the museum's cultural relics. [ABSTRACT FROM AUTHOR]

Polymer hydrogel electrolytes combine the advantages of solvent-free solid electrolytes and liquid electrolytes, with a specific ion migration rate, excellent flexibility and safety. However, the critical limitation to the application of hydrogel electrolytes is that their ionic conductivity hardly rivals that of liquid electrolytes. In this work we design zwitterionic hydrogel (PMH) electrolytes with ultrahigh ionic conductivity, whose ionic conductivity is 140–160% that of alkali metal chloride solutions (LiCl, NaCl and KCl) and 130% that of sulfuric acid solution. This fascinating discovery is attributed to the ice-like clathrate structure formed via electrostatic induction between zwitterionic groups and water molecules. This delicate structure affects the hydration state of nearby ions and improves ion mobility. Meanwhile, the dipole–dipole interaction facilitates the dissociation of ion clusters, further increasing the ionic conductivity. This work provides an effective way to obtain electrolytes with ultrahigh ionic conductivity, representing an important step forward for practical applications in energy storage. [ABSTRACT FROM AUTHOR]

Nucleic acid methylations are important genetic and epigenetic biomarkers. The formation and removal of these markers is related to either methylation or demethylation. In this review, we focus on the demethylation or oxidative modification that is mediated by the 2-oxoglutarate (2-OG)/Fe(II)-dependent AlkB/TET family enzymes. In the catalytic process, most enzymes oxidize 2-OG to succinate, in the meantime oxidizing methyl to hydroxymethyl, leaving formaldehyde and generating demethylated base. The AlkB enzyme from Escherichia coli has nine human homologs (ALKBH1-8 and FTO) and the TET family includes three members, TET1 to 3. Among them, some enzymes have been carefully studied, but for certain enzymes, few studies have been carried out. This review focuses on the kinetic properties of those 2-OG/Fe(II)-dependent enzymes and their alkyl substrates. We also provide some discussions on the future directions of this field. [ABSTRACT FROM AUTHOR]

The isothermal crystallization kinetics of nylon 6/graphene (NG) composites prepared by in situ polymerization was investigated by differential scanning calorimetry. The Avrami equation was used to study the crystallization kinetics. Comparing with nylon 6, it is found that the NG composites (NG-0.1, NG-0.5, and NG-1.0, where the number describes the wt% content of graphene) had higher crystallization rates; the crystallization rate increased remarkably with 0.1 wt% graphene. However, too many crystallization nuclei could not accelerate the crystallization process effectively. The [t.sub.max] values obtained from the plots of heat flow versus time were in agreement with the [t.sub.max] values calculated from the half time of crystallization when the graphene content was lower than 1.0 wt%, which means that the values of the Avrami parameters calculated from the half time of crystallization might be in better agreement with the actual crystallization mechanism than that determined from the Avrami plots. The n values of the NG composites ranged between 1.1 and 1.8, which can be interpreted as meaning both one-dimensional and two-dimensional crystallization growth occurred during isothermal crystallization process. The activation energies, which were determined by the Arrhenius' method, varied within the range from -188 to -142 kJ/mol., INTRODUCTION In 2004, single layers of graphene were successfully prepared by Geim and co-workers at Manchester University in a simple experiment [1], As a new material, the modification of graphene/graphene [...]