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Novel and stringent automotive exhaust gas emissions standards are urgently needed to counter the problems posed by the worsening global climate and environment. However, the traditional cordierite‐based honeycomb ceramics substrates with ultimate pore density have seriously restricted the establishment of new emission standards. Herein, we introduce a novel robust substrate with tailored volume‐specific surface area and low heat capacity. This substrate employs the synergy of high‐strength ceramic fibers and ultrathin TiO2 nanosheets. The micro‐sized fibers provide support to ensure structural strength during the catalytic reaction, while the nanosheets play the dual role of connecting the fibers and providing a high surface area for catalyst immobilization. The new three‐dimensional (3D) microarchitecture exhibits a high volume‐specific surface area of 3.59×104 cm2/cm3, a compressive strength of 2.01 MPa, and remarkable stability after high‐speed air erosion at 800 °C. The honeycomb‐like structure exhibit low resistance to gas flow. Furthermore, after loading with Pt and Pd nanoparticles, the composite 3D microarchitecture delivered an excellent catalytic performance and prominent structural stability, with a super low light‐off temperature of 150 °C. The outstanding mechanical and thermal stability and the high surface area and light‐off temperature of the new substrate indicate its potential for use as a highly efficient catalytic carrier to meet the next‐generation auto emissions standards. [ABSTRACT FROM AUTHOR]

Geographic and climatic differences between islands and continents may affect the evolution of their biota, and promote divergent selection in species distributed in both landscapes. To assess spatial‐genetic structure, we genotyped 18 expressed sequence tag‐simple sequence repeat (EST‐SSR) loci and sequenced two mtDNA markers (ND5 and COI) and one nuclear marker (EF1α) in two subspecies of the butterfly Parantica sita. Compared with nuclear markers, mtDNA had a stronger signal of population structure. Approximate Bayesian computation (ABC) suggested that a continuous‐gene‐flow model best described the data. According to this model, the two subspecies diverged approximately 23.1 kya, with 10 times more introgression from the continental (ssp. sita) to the insular subspecies (ssp. niphonica) than vice versa. Ecological niche modelling was performed to predict the paleo‐ and current potential distributions and elucidate the geohistorical process, which revealed a northeastern, insular origin. Winter precipitation and annual temperature range were the main determinants of the subspecies distributions. Maximum‐likelihood population‐effects models showed that the population differentiation of the insular and continental subspecies was primarily affected by environmental resistance and local climate. Sex‐biased migration capacity and long‐term precipitation‐driven divergence between the continental and insular lineages shaped the current genetic structure of P. sita. Evidence from the nuclear markers confirmed intersubspecific gene flow despite adaptive divergence between the subspecies. These results imply that the continental subspecies is still capable of returning to the island and introgressing with the insular subspecies. [ABSTRACT FROM AUTHOR]

Nowadays, the research on materials science is rapidly entering a phase of data‐driven age. Machine learning, one of the most powerful data‐driven methods, have been being applied to materials discovery and performances prediction with undoubtedly tremendous application foreground. Herein, the challenges and current progress of machine learning are summarized in materials science, the design strategies are classified and highlighted, and possible perspectives are proposed for the future development. It is hoped this review can provide important scientific guidance for innovating materials science and technology via machine learning in the future. [ABSTRACT FROM AUTHOR]

Aim: The Massenerhebung effect (Mass elevation effect) refers to heat‐ or wind‐driven altitudinal distribution patterns of temperature‐dependent parameters among massifs with narrower range and lower elevation around peripheral and isolated mountains compared to core and continuous ones. Although common in ecology, this effect is rarely discussed in population genetics. Here, we use genetic markers to reveal population genetic patterns and also test the mountain‐ and sky‐barrier hypotheses relevant to the Massenerhebung distribution pattern of Acer morrisonense in Taiwan's rugged topography and varied local climates. Location: The alpine and cloud forest of Taiwan. Taxon: Acer morrisonense Hayata. Methods: Two chloroplast DNA (cpDNA) fragments and 17 expressed sequence tag‐simple sequence repeat (EST‐SSR) loci, respectively, from 200 to 286 individuals were used to elucidate the phylogeographic pattern of pollen and seed dispersal of A. morrisonense. These data were combined with ecological niche modeling (ENM) to infer distribution range shifts and refugia. We also correlated the genetic‐divergence indices with spatial factors to clarify latitudinal and altitudinal effects on genetic diversity. Results: The incongruent phylogeographic patterns of genetic distributions between nuclear and cpDNA markers indicate unhindered pollen flow but spatially constrained seed dispersal. Taken together with ENM, the genetic pattern further reflects historical colonization from central‐mountain refugia to edges since the Holocene. The Massenerhebung reduces the gene flow by the surrounding mountains and also causes lower genetic diversity compared to central alpine populations. Main conclusions: This study is the first to reveal the influence of Massenerhebung effect on cpDNA genetic structure of montane trees and reflect the spatial trends of seed dispersal. This population genetic pattern can also be attributed to the demography‐related range shifts with paleoclimate fluctuations under complex mountain topography, supporting the mountain‐barrier hypothesis. The results have important implications for conserving the genetic diversity of species with a wide altitudinal distribution range. [ABSTRACT FROM AUTHOR]

Polymers play a crucial role in promoting the progress of high‐performance inverted perovskite solar cells (PSCs). However, few polymers have simultaneously achieved defect passivation and device encapsulation in PSCs. Herein, a telechelic silicone polymer (poly(dimethylsiloxane‐co‐methylsiloxane acrylate) [PDMA]) is introduced, which possesses crosslinking capability to enable structure regulation through a condensation reaction. By leveraging the advantages of the polymers before and after crosslinking, a synergistic strategy of defect healing and device encapsulation for PSCs is developed via the application of the targeted polymer. PDMA as additives anchors tightly at the grain boundaries (GBs) and bridges the perovskite grains, achieving defect passivation and GBs crosslinking, increasing the efficiency of inverted PSCs from 22.32% to 24.41%. Crosslinked PDMA (CPDMA) is used as an encapsulant to encapsulate the entire device, enabling non‐destructive encapsulation at room temperature and inhibiting perovskite degradation under photothermal aging. Remarkably, the PDMA‐modified device with CPDMA encapsulation maintains 98% of its initial efficiency after 1200 h under continuous illumination at 55 ± 5 °C and retains 95% of its original efficiency after 1000 h of damp heat testing, meeting one of the IEC61215:2016 standards. [ABSTRACT FROM AUTHOR]

Metal‐based nanocatalysts supported on carbon have significant prospect for industry. However, a straightforward method for efficient and stable nanocatalysts still remains extremely challenging. Inspired by the structure and comptosition of cell walls and membranes, an ion chemical bond anchoring, an in situ carbonization coreduction process, is designed to obtain composite catalysts on N‐doped 2D carbon (C‐N) loaded with various noble and non‐noble metals (for example, Pt, Ru, Rh, Pd, Ag, Ir, Au, Co, and Ni) nanocatalysts. These 2 nm particles uniformly and stably bond with the C‐N support since the agglomeration and growth are suppressed by anchoring the metal ions on the cell wall and membrane during the carbonization and reduction reactions. The Pt@C‐N exhibits excellent catalytic activity and long‐term stability for the hydrogen evolution reaction, and the relative overpotential at 100 mA cm−2 is only 77 mV, which is much lower than that of commercial Pt/C and Pt single‐atom catalysts reported recently. [ABSTRACT FROM AUTHOR]

N‐alkyl anilines are a series of common and versatile compounds which not only have been used as reaction solvents, acid‐accepters, and organic‐bases, but also in synthesis of dyes, pharmaceuticals, and anti‐colodal. The N‐methyl and/or N,N‐dimethyl anilines are the most representative ones among these. Due to their widespread uses, numerous works have been reported on synthetic strategies in the past decades. The studies on N−H methylations of anilines mainly focus on selection of reagents, selection of catalysts, or ligands design. Different transition‐metals, e. g., Ir, Ru, Pd, and et. al, with different ligands have been used in the methylation protocols. Methanol (CH3OH), carbon dioxide (CO2), formaldehyde (HCHO), or dimethyl carbonate ((CH3)2CO3) was used as C source, and hydrogen (H2) or silanes as H source. In this work, we would like to summarize the latest advances on the synthesis of N‐methyl (N,N‐dimethyl included) anilines and derivatives. This review provides an overview of reactants and catalyst, as well as an emphasis on the scope of substrates and proposed reaction mechanism for each work. [ABSTRACT FROM AUTHOR]

Lanthanum hexaaluminate is a promising candidate to establish yttria partially stabilized zirconia as a thermal barrier coating material for super alloy due to their remarkable stability and thermophysical performance. In order to understand the relationship between the structure and properties and gain new low thermal conducting materials, the LnMgAl11O19 (LnMA, Ln: La, Pr, Nd, Sm, Eu, Gd) materials were synthesized firstly and further used to produce the LnMA ceramics. With the increasing relative atomic mass of the replaced Ln3+ ions from La to Gd, the lattice parameters and grain sizes of the LnMA platelets decrease, while the mechanical properties increase, and the thermal physic properties decrease. The GdMgAl11O19 ceramics obtain the lowest thermal conductivity with the value of 1.91‐1.78 W/m K in the range from room temperature to 800°C, which could be considered as a promising candidate for application in thermal barrier coating materials. These results could further provide reference for developing novel materials lower thermal conductivity. [ABSTRACT FROM AUTHOR]

In the presence of a nickel catalyst, 1,3-butadiene undergoes selective dimerization and alkylarylation with alkyl fluorides and aryl Grignard reagents to give 1,6-octadienes with alkyl and aryl groups at the 3- and 8-positions, respectively, by the consecutive formation of three carbon-carbon bonds. The formation of an anionic nickel complex plays an important role in forming C−C bonds with alkyl fluorides. [ABSTRACT FROM AUTHOR]

In the presence of a nickel catalyst, 1,3-butadiene undergoes selective dimerization and alkylarylation with alkyl fluorides and aryl Grignard reagents to give 1,6-octadienes with alkyl and aryl groups at the 3- and 8-positions, respectively, by the consecutive formation of three carbon-carbon bonds. The formation of an anionic nickel complex plays an important role in forming C−C bonds with alkyl fluorides. [ABSTRACT FROM AUTHOR]

To study the improvement in solid particle impact erosion wear resistances of 3 mol% yttria-stabilized zirconia (3YSZ) ceramic at elevated temperatures up to 1400°C, 2 wt% LaMgA111O19 was added into 3YSZ to prepare LaMgA111O19-3YSZ ceramic for erosion resistance tests with angular corundum abrasive particles. The testing results show that the volume erosion rates of 3YSZ and LaMgA111O19-3YSZ ceramic were similar in the temperature range from room temperature to 600°C, then exhibited a sharp increase from 600°C to 1200°C, and dropped again at 1400°C. It was mainly caused by the change in material removal mechanisms from plastic deformation below 600°C to the interaction of transverse cracks in the temperature range from 600°C to 1400°C. The solid particle impact erosion wear properties of 3YSZ ceramic in the temperature range from 600°C to 1400°C were successfully improved by the addition 2 wt% LaMgA111O19 platelets. Comparing with the volume erosion rate of pure 3YSZ ceramic (0.687 mm3/g) at 1200°C, the value of LaMgA111O19-3YSZ ceramic (0.551 mm3/g) has been decreased by 20%. [ABSTRACT FROM AUTHOR]

Novel LaMgAl11O19:Tm3+, Dy3+ phosphors were prepared utilizing a high-temperature solid-state reaction method. The phase formation, luminescence properties, energy-transfer mechanism from the Tm3+ to the Dy3+ ions, the thermal stability, and CIE coordinates were investigated. When excited at 359 nm, the LaMgAl11O19: xTm3+ phosphors exhibit strong blue emission bands at 455 nm. After codoping with Dy3+ and excitation at 359 nm, the LaMgAl11O19:0.03Tm3+, yDy3+ phosphors emitted white light consisting of the characteristic emission peaks of Tm3+ and Dy3+. The Dy3+ emission intensity increased with the Dy3+ concentration due to the energy transfer from Tm3+ to Dy3+, and concentration quenching due to the high Dy3+ doping concentration (y = 0.1 mol) did not occur. The calculation of the CIE coordinates of the LaMgAl11O19: Tm3+, yDy3+ phosphors revealed the tunability of the emission color from blue to bluish-white and to white by changing the excitation wavelength and the doping concentration. An energy transfer from Tm3+ to Dy3+ by dipole-dipole interaction was confirmed by the decay curve, lifetime, and energy-transfer efficiency measurements. When excited at 359 nm, the LaMgAl11O19:Tm3+, Dy3+ phosphor also showed good thermal stability, suggesting that it can be used in white LEDs excited by a GaN-based ultraviolet LED. [ABSTRACT FROM AUTHOR]

LaMgAl11O19-3 mol% yttria partially stabilized zirconia ceramics were successfully prepared by pressureless sintering at 1550°C for 3 h. The ceramic's mechanical properties were measured, and the phase composition and microstructure observed using X-ray diffraction and scanning electron microscopy. The results show that the mechanical properties of the ceramic were initially improved on addition of LaMgAl11O19, but further additions were detrimental. When the amount of LMA added was equal to 2 wt.%, the bending strength and fracture toughness reached 812 ± 37 MPa and 14.0 ± 0.3 MPa·m1/2. This equates to an increase of 8.0% and 6.9% compared with untreated 3 mol% yttria partially stabilized zirconia (3 YSZ) ceramic, respectively. However, the bending strength and fracture toughness both decreased when the amount of LaMgAl11O19 added was 4 and 6 wt.%. A crack propagation and force analysis of the crack tips in LaMgAl11O19-platelet-reinforced 3 YSZ ceramic were also carried out. The results indicate that phase transformation and crack deflection were the dominant toughening mechanisms in the LaMgAl11O19-3 YSZ ceramic. At the same time, energy dissipation by the LaMgAl11O19 platelets also helps to restrain crack propagation in the matrix, which improves toughness more effectively. [ABSTRACT FROM AUTHOR]

In order to solve the severe erosion of kiln refractories for the high‐temperature treatment used during the process of recovering valuable metal elements from waste lithium batteries, this study investigates the low‐cost, no‐firing preparation technology of erosion‐resistant SiC–C–t‐ZrO2 composites with self‐prepared t‐ZrO2–SiC–C powder, as well as silicon carbide and flake graphite as the main raw materials, and phenolic resin as the binding agent. (1) The effects of different t‐ZrO2–SiC–C powder additions and heat treatment temperatures on the properties of SiC–C–t‐ZrO2 composites were studied in details. (2) The erosion resistance of SiC–C–t‐ZrO2 composites to after‐use lithium battery waste was evaluated using the static crucible method. The mechanical properties of the t‐ZrO2–SiC–C composites was the best that its cold modulus of rupture (CMOR) was 11.37 MPa and cold crush strength (CCS) was 41.96 MPa when heat treatment temperature was 600°C and content of t‐ZrO2–SiC–C powder was 10 wt%. At that condition, the bulk density of samples reached to 3.15 g/cm3 and apparent porosity of it was only at 11.09% which means that the samples designed in this work are compacted enough. In the erosion test, the t‐ZrO2–SiC–C composites had an excellent resistance to erosion of lithium battery waste. [ABSTRACT FROM AUTHOR]

Using fly ash to synthesize zeolite molecular sieves can improve the reuse value of coal fly ash resources, reduce the synthesis cost of the zeolites, and protect the ecology. A novel approach was proposed to prepare zeolite socony mobil‐5 (ZSM‐5) zeolite via one‐pot hydrothermal synthesis. The mesoporous ZSM‐5 synthesized by adjusting the molar ratio of chemical reagents has higher crystallinity, larger specific surface area, and more adsorption sites. An analysis of methylene blue (MB) adsorption on mesoporous ZSM‐5 was conducted at many different adsorption parameters, including solution concentration, temperature, and duration of adsorption. The Langmuir model can objectively describe the adsorption behavior of MB on ZSM‐5, and the adsorption characteristics of MB on ZSM‐5 are better described by the pseudo‐second‐order kinetic model. The thermodynamic model provides the adsorption behavior as an endothermic reaction. [ABSTRACT FROM AUTHOR]

The level of dentition asymmetry in snail‐eating snakes may reflect their prey choice and feeding efficiency on asymmetric land snails. The three species of Pareas snakes (Squamata: Pareidae) in Taiwan, which form partially sympatric distribution on the island, provide a potential case to test the hypothesis of niche partitioning and character displacement with regard to dentition asymmetry and specialisation in feeding behaviour.In this study, behavioural experiments confirmed that P. formosensis feeds exclusively on slugs, whereas P. atayal and P. komaii consumed both. However, P. atayal more efficiently preys on land snails than P. komaii, exhibiting a shorter handling time and fewer mandibular retractions.Micro‐CT and ancestral character reconstruction demonstrated the lowest asymmetry in P. formosensis (the slug specialist), the highest dentition asymmetry in P. atayal (the land snail specialist) and flexibility in P. komaii (the niche switcher): increased dentition asymmetry when sympatrically distributed with the slug eater (character displacement), and decreased asymmetry when living alone (ecological niche release).Ecological niche modelling showed that the distribution of P. formosensis is associated with the presence of slugs, while that of P. atayal could be explained by the land snails.Combining the results from morphology, phylogeny, behavioural experiments and ecological niche modelling, we showed that competition in the sympatric region might have facilitated character displacement among congeners, while the absence of competition in allopatric region has led to ecological niche release. [ABSTRACT FROM AUTHOR]

A novel Ni‐based initiator is designed and synthesized for obtaining a hydroxyl‐terminated polybutadiene (HTPB) with higher cis‐1,4 unit content (≥90%). By investigating the effect of the butadiene skeleton structure and counterion on initiating efficiency, it is found that [η3‐Ni(CH2CHCHCH2OOCH3)][BPhF4] complex is a feasible combination to be used as an initiator. 1H‐NMR data prove that the initiator structure obtained is in accordance with the original design. The result of 1H‐NMR, 13C‐NMR, FT‐IR confirms that HTPB synthesized not only gains a significant amount in cis‐1,4 unit content (≥90%) compared with the HTPBs by free radical and anionic polymerizations, but also its molecular weight and molecular weight distribution can be effectively controlled during synthesis process. Because of the much higher cis‐1,4 unit content, the glass‐transition temperature of HTPB obtained via [η3‐Ni(CH2CHCHCH2OOCH3)][BPhF4] is markedly reduced; as a result, its low‐temperature mechanical property can also be significantly improved. A novel Ni‐based initiator Ni(CH2CHCHCH2OOCH3)][BPhF4] is designed and synthesized for obtaining a hydroxyl‐terminated polybutadiene (HTPB) with higher cis‐1,4 unit content (≥90%). The glass‐transition temperature of HTPB obtained via [η3‐Ni(CH2CHCHCH2OOCH3)][BPhF4] is markedly reduced; as a result, its low‐temperature mechanical property can also be significantly improved. [ABSTRACT FROM AUTHOR]

An efficient I2/AgNO3 co‐promoted one‐pot annulation of alkynes with 1,2‐arylenediamines into quinoxalines is reported. The reaction proceeded smoothly under mild conditions and rapidly generated quinoxalines (37 examples) in good to excellent yields (up to 83 %) with a good tolerance of functional groups. Moreover, π‐conjugated polycyclic quinoxaline derivatives could also be successfully synthesized by this one‐pot strategy. Furthermore, a gram‐scale reaction of the one‐pot reaction is also investigated. Finally, a plausible mechanism for the one‐pot reaction is proposed. [ABSTRACT FROM AUTHOR]

Environmental pollution and the energy crisis have promoted the development of clean energy as well as new‐generation energy storage systems. Potassium ion batteries (PIBs) have emerged as a possible alternative to lithium‐ion batteries due to their abundant reserves, low cost, and impressive electrochemical performance. However, the search for suitable cathode materials has become particularly crucial. Recently, Prussian blue (PB) has been investigated as a potential cathode material for PIBs, which has an open three‐dimensional framework to accommodate a large volume of potassium ions and adjustable composition for different applications. In this review, Prussian blue and its analogues (PBAs) and their application in PIBs were summarized detailly. We presented the composition, structure, potassium ion storage mechanism, preparation process of PBAs, and then focus on the performance optimization methods of the PBAs, including transition metal doping and conductive material adding into PBAs. Finally, the challenges as well as the outlook on the future development of PBAs were proposed for further application in this battery system. [ABSTRACT FROM AUTHOR]

A cryptic lineage is a genetically diverged but morphologically unrecognized variant of a known species. Clarifying cryptic lineage evolution is essential for quantifying species diversity. In sympatric cryptic lineage divergence compared with allopatric divergence, the forces of divergent selection and mating patterns override geographical isolation. Introgression, by supplying preadapted or neutral standing genetic variations, can promote sympatric cryptic lineage divergence via selection. However, most studies concentrated on extant species introgression, ignoring the genetic legacy of introgression from extinct or unsampled lineages ("ghost introgression"). Cycads are an ideal plant for studying the influence of ghost introgression because of their common interspecific gene flow and past high extinction rate. Here, we utilized reference‐based ddRADseq to clarify the role of ghost introgression in the evolution of a previously identified sympatric cryptic lineage in Cycas revoluta. After re‐evaluating the evolutionary independency of cryptic lineages, the group‐wise diverged single‐nucleotide polymorphisms among sympatric and allopatric lineages were compared and functionally annotated. Next, we employed an approximate Bayesian computation method for hypothesis testing to clarify the cryptic lineage evolution and ghost introgression effect. SNPs with the genomic signatures of ghost introgression were further annotated. Our results reconfirmed the evolutionary independency of cryptic lineage among C. revoluta and demonstrated that ghost introgression to the noncryptic lineage facilitated their divergence. Gene function related to heat stress and disease resistance implied ecological adaptation of the main extant populations of C. revoluta. [ABSTRACT FROM AUTHOR]

A large amount of metallurgical solid waste accumulation poses a serious threat to the environment. Study on synergistic reinforcement of synthetic process of metallurgical solid waste‐based ceramics with fly ash is of great significance in reducing environmental pollution and resource utilization. A metallurgical solid waste‐based ceramic used as building ceramic was developed with the erosion part of used MgO–C bricks and fly ash as main raw materials, and the amount of solid waste added to the prepared ceramics was at least 60 wt% and up to 90 wt%. The effects of fly ash content and sintering temperature on the crystalline phase transitions, morphologies, and the main physical and mechanical properties of ceramics were investigated by X‐ray diffraction, scanning electron microscopy, and mechanical testing. The results show that the obtained ceramics presented maximum bending strength and minimum water absorption, 80.14 MPa and 5.04%, respectively, when the raw material proportions were the erosion part of used refractories accounted for 60 wt%, fly ash 20 wt%, pyrophyllite 10 wt%, and quartz sands 10 wt%, and the process parameters were the sintering temperature 1150°C, sintering time 120 min, and molding pressure 15 MPa. [ABSTRACT FROM AUTHOR]

Ni-catalyzed dimerization of butadiene and subsequent alkylarylation reaction with arylmagnesium bromide and primary alkyl fluorides constitutes an efficient synthesis of 3-alkyl-8-aryl-1,6-octadienes. [ABSTRACT FROM AUTHOR]

Starke C‐F‐Bindungen wurden mit einem anionischen Nickelkatalysator durchtrennt, um die Alkylketten der Alkylfluoride in die gewünschten Kupplungsprodukte einzubauen. In der Zuschrift auf S. 5640 ff. beschreiben N. Kambe, T. Iwasaki et al. eine nickelkatalysierte regio‐ und stereoselektive Mehrkomponentenreaktion von Alkylfluoriden, Aryl‐Grignard‐Reagentien und zwei Molekülen 1,3‐Butadien, die durch die besondere Reaktivität anionischer Bis(allyl)nickel‐Komplexe gegenüber C‐F‐Bindungen ermöglicht wird. [ABSTRACT FROM AUTHOR]

Supramolecular copolymers can not only enrich the diversity of the polymer backbone but also exhibit certain special and improved properties compared with supramolecular homopolymers. However, the synthesis procedure of supramolecular copolymers is relatively complicated and time-consuming. Herein, a simple transformation from an AB2-based supramolecular hyperbranched homopolymer to an AB2+CD2-based supramolecular hyperbranched alternating copolymer by the 'competitive self-sorting' strategy is reported. After adding CD2 monomer, which bears a competitive neutral guest moiety ( TAPN) and two receptive benzo-21-crown-7 host moieties ( B21C7), to the as-prepared AB2-type supramolecular hyperbranched homopolymer constructed by the self-assembly of dialkylammonium salt ( DAAS, A group)-functionalized pillar[5]arene ( MeP5, B groups) monomers, the initial homopolymer structure is disrupted and then reassemble into a new supramolecular hyperbranched alternating copolymer based on the competitive self-sorting interaction between MeP5- TAPN and B21C7- DAAS. This study supplies a convenient approach to directly transform supramolecular homopolymers into supramolecular copolymers. [ABSTRACT FROM AUTHOR]

Aim: Rapid global warming is threatening global biodiversity, and it will likely lead to varying degrees of local adaptation, particularly amongst plant species. Besides, rising temperatures frequently result in upslope distribution shifts towards climatic optima (i.e. the escalator effect) within a limited dispersal space, such as in insular environments. Here, we integrated ecological and genetic approaches to investigate how climate change will impact the genetic compositions and spatial distributions of Taiwan's endemic maple Acer caudatifolium. Location: Taiwan. Methods: We estimate the distribution range shifts of A. caudatifolium under climate change through species distribution modelling (SDM). We also use 368 genotyped samples to infer dispersal and genetic hotspots and quantify the contributions of geography/environments to genetic variations. We further assess the potential risk to A. caudatifolium under different climate warming scenarios. Results: We detected three genetic diversity hotspots near mountainous glacial refugia and two dispersal hotspots in northern Taiwan and the central‐to‐southern Central Mountain Range. Overall range reductions and an altitudinal upslope shift were observed in SDM. Using both linear and nonlinear regression approaches, we found that genetic variation was significantly associated with geographic distance and elevation‐related climatic variables. The potential risk analysis revealed that the northernmost summit‐dwelling populations were the most vulnerable. Furthermore, the major risk factor differed amongst populations: for central populations, temperature and precipitation jointly determined the potential risk, whereas precipitation was the only risk factor for northern and southern populations. Main conclusions: This case study demonstrates how various climate factors, mountain height and the availability of corridors jointly determine the demographic fates and sustainability of island maples in the face of climate change. This study also provided estimates of the implications of global warming, which can be conducive to developing appropriate conservation strategies. [ABSTRACT FROM AUTHOR]

In this work, the mechanical properties and solid particle erosion wear behavior of LaMgAl11O19-Al2O3 ceramics toughened and reinforced with LaMgAl11O19 platelets were investigated. The effects of LaMgAl11O19 additions, impingement angles (30°, 45°, 60°, 75°, and 90°), and erosion temperatures varying from room temperature to 1400°C on the erosion rates and material removal mechanisms of LaMgAl11O19-Al2O3 composites were systematically studied. The results indicated that LaMgAl11O19-Al2O3 ceramics exhibited superior erosive wear resistance compared to monolithic Al2O3 ceramics at room and elevated temperatures due to their enhanced mechanical properties and improved microstructure resulting from the introduction of an appropriate amount of LaMgAl11O19 platelets. Examination of the eroded surfaces of LaMgAl11O19-Al2O3 composites revealed that erosion temperatures and impingement angles play important roles in determining the erosion behavior and mechanisms of the tested materials. For the case of elevated temperature and oblique erosion, plowing and subsurface intergranular fracture are the predominant mechanisms resulting in material removal, whereas at room temperature and normal impact, the erosion process of the targets is primarily dominated by grain ejection and lateral crack intersection. [ABSTRACT FROM AUTHOR]

Hierarchical nano‐micro carbon spheres porous carbon composites are successfully synthesized derived from Euryale ferox shells by the in‐situ decoration of the porous carbon with carbon spheres from carboxymethyl cellulose under the activation of KOH. Effects of fabrication and activation manner on surface area of porous carbons were investigated. The influence of activation temperature, impregnation ratio and modifier were analyzed. The specific surface area, pore volume and average pore diameter of porous carbon was characterized by N2 adsorption isotherms. Porous carbon produced at 800 °C with an impregnation ratio of 3, 2 hours of carbonization time, 20 hours immersion time has been found 2506 m2 g−1, 1.515 cm3 g−1 and 2.4 nm of the optimum specific surface area, pore volume and average pore diameter, respectively. The result of Fourier‐infrared spectroscopy analysis of the prepared porous carbon confirmed that it has abundant functional groups on the surface. The scanning electron micrographs of the prepared porous carbon indicated that a well‐developed pore structure was formed during the experiment. [ABSTRACT FROM AUTHOR]

Silicoaluminophosphate zeolite (SAPO‐34) has been attracting increasing attention due to its excellent form selection and controllability in the chemical industry, as well as being one of the best industrial catalysts for methanol‐to‐olefin (MTO) reaction conversion. However, as a microporous molecular sieve, SAPO‐34 easily generates carbon deposition and rapidly becomes inactivated. Therefore, it is necessary to reduce the crystal size of the zeolite or to introduce secondary macropores into the zeolite crystal to form a hierarchical structure in order to improve the catalytic effect. In this review, the synthesis methods of conventional SAPO‐34 molecular sieves, hierarchical SAPO‐34 molecular sieves and nanosized SAPO‐34 molecular sieves are introduced, and the properties of the synthesized SAPO‐34 molecular sieves are described, including the phase, morphology, pore structure, acid source, and catalytic performance, in particular with respect to the synthesis of hierarchical SAPO‐34 molecular sieves. We hope that the review can provide guidance to the preparation of the SAPO‐34 catalysts, and stimulate the future development of high‐performance hierarchical SAPO‐34 catalysts to meet the growing demands of the material and chemical industries. [ABSTRACT FROM AUTHOR]

The structure of niobium-doped SrBiTiO was calculated by using density function and discrete variation method (DFT-DVM). By comparing the total energy of different doping sites, the total energy is found to be lower when Nb ion was substituted into the Ti site in the upper perovskite layer, which is far from the two bismuth (Bi) ions in the perovskite layer. The bonding strength of Nb (3)-O increases and the electronic conductivity of the SBT decreases after Nb doping. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

Abstract: We report here the characterization of the yeast mto2 null mutants carrying wild-type mitochondrial DNA or 15S rRNA C1049G allele. The amounts of mitochondrial tRNALys, tRNAGlu, tRNAGln, tRNALeu, tRNAGly and tRNAMet were markedly decreased but those of tRNAArg and tRNAHis were not affected in mto2 strains. The mto2 strains exhibited significant reduction in the aminoacylation of tRNALys, tRNALeu but almost no effect in those of tRNAHis. Interestingly, the strain carrying the C1049G allele exhibited an impairment of aminoacylation of those tRNAs. Furthermore, the steady-state levels of mitochondrial mRNA CYTB, COX1, COX2, COX3, and ATP6 were markedly decreased in mto2 strains. These data strongly indicate that unmodified tRNA caused by the deletion of MTO2 caused the instability of mitochondrial tRNAs and mRNAs and impairment of aminoacylation of tRNAs. [Copyright &y& Elsevier]

In the desert, plant diaspore spreading usually relies on both external vectors, such as wind, and internal factors, such as diaspore shape. Ammopiptanthus mongolicus is a heterocarpous shrub species in the cold desert in northwest China. Mature pods may have dehisced or not yet dehisced when abscising, and the dehiscent pods may be twisted or flattened. The propagation distances of diaspores might vary due to differences in their buoyancies in upward air and ground friction according to pod shape. The wind tunnel experiments were conducted to measure the horizontal displacement upon fruit dropping (D1) and the wind‐blown distance traveled by a fallen pod (D2) of A. mongolicus. A generalized linear mixed model and generalized linear model were used to test the effects of pod shape, release height, wind speed and ground substrate type on the spread distance of pods. D1 is jointly determined by the effects of release height and pod shape. Wind speed, pod shape and ground substrate type together affect D2. A twisted pod has higher dispersibility than a flat pod, and dehiscent pods spread further than indehiscent ones. The positive correlation of D1 and D2 indicates that the difference in pod shape additively broadens the range of seed‐spreading distance. Differential seed‐spreading properties could be adaptively advantageous to disperse the risks associated with diasporic dissemination compared with the maintenance of a single optimal dissemination characteristic. Thus, heterodiaspory is an advantageous adaptive characteristic for seed spreading in the windy, arid and harsh desert environment. [ABSTRACT FROM AUTHOR]

A shape‐stabilized composite phase change material (SS‐CPCM) with paraffin (PA) and biological porous carbon (BPC) was prepared. Freeze‐dried biological‐cellulose include abandoned pomelo peel (APP) and tangerine peel (ATP) were carbonized in vacuum at 800 °C to obtain BPC to be used as a matrix material to prevent PA leakage and enhance thermal conductivity. A vacuum impregnation process was utilized to obtain the SS‐CPCM. Scanning electron microscopy showed that BPC (carbonized APP is subsequently referred to as BPC1 and carbonized ATP as BPC2) has a porous, honeycomb‐like structure, and that the paraffin encapsulated by the pores is evenly distributed. The SS‐CPCM2 (made from ATP) had the highest thermal conductivity (2.10 W/m K), which is 1.89 and 10 times that of the SS‐CPCM1 (made using APP) and pure PA, respectively. Differential scanning calorimetry and thermo‐gravimetric analysis were applied to determine the thermal performance and thermal reliability of the SS‐CPCM. Therefore, the prepared SS‐CPCM has potential in the field of energy storage. [ABSTRACT FROM AUTHOR]

Phase‐change materials (PCMs) have been widely investigated as candidates for thermal energy storage and solar thermal energy conversion. However, low thermal conductivity and poor shape stability during phase transition processes are detrimental to their practical applications. In this study, we designed composite PCMs based on carbon foam (CF) via the vacuum impregnation method to overcome these problems. CF with 3D interconnected microporous structures and good compressive strength was fabricated from phenolic resin (PF) using a combined process of carbonization and sacrificial template techniques. The developer material is considered a promising support material for PCMs. The as‐prepared polyethylene glycol/CF composite (PCC) exhibited a high energy‐storage density with a melting enthalpy of 135.7 J/g, and the thermal conductivity was enhanced by 109.8% compared to that of pure polyethylene glycol. In addition, the PCC showed excellent thermal stability and leakage‐proof performance after 100 heating/cooling cycles and good compressive strength. Because of the simple preparation process and low cost, PCC is a promising material for various thermal energy storage applications, especially in building energy storage systems. [ABSTRACT FROM AUTHOR]

Needle‐like α‐Si3N4 with unique structures has potential application in both field emission devices and tips for atomic force microscopes. Single‐crystalline, α‐Si3N4 nanoneedles have been prepared by using an improved chemical vapor deposition (CVD) method at 1200°C for 3 hours. The phases, chemical composition, and microstructure of the as‐prepared products were determined by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) equipped with EDS. The as‐synthesized products show a needle‐like morphology with hundreds of micrometers in length and nanometer‐featured tips. The nanoneedles show a α‐Si3N4@SiOx core‐shell heterostructure as characterized by TEM, with single‐crystalline α‐Si3N4 core and an insulating amorphous silicon oxide shell. The growth of α‐Si3N4 nanoneedles corresponds to vapor‐liquid‐solid cap‐growth and base‐growth mechanism. Photoluminescence (PL) properties of the products were also characterized. An obvious emission peak at 400 nm under 254 nm UV excitation was observed. The nanoneedle morphology and photoluminescence properties of the products have potentials to be used in future optoelectronic nanodevices. [ABSTRACT FROM AUTHOR]

β‐SiC materials have been seen as the third‐generation semiconductor widely used in kinds of photoelectric device, high temperature electronics, and other fields. Compared with ordinary semiconductors, β‐SiC materials have huge potential application in replacing monocrystalline silicon in extreme environments because of their numerals extraordinary chemical and physical properties. Based on this, β‐SiC nanowires obviously are more desirable in any way. Here, we present a modified chemical vapor deposition (CVD) method to synthesis β‐SiC nanowires, which needs no protect gas, and transfer it to Si/SiO2 substrates equipped with Au electrodes. The microstructure of the as‐prepared samples is tested by field emission scanning electron microscopy (FESEM). The humidity sensing performance of electronic device is measured by electrochemical workstation test equipment. It shows that the resistance of β‐SiC nanowires increases with increasing environment humidity within very short response/recovery time‐0.5 seconds/0.5 seconds and also performs excellent cycling stability. Such advantage superiorities make it highly possible to apply β‐SiC nanowires into various environments. [ABSTRACT FROM AUTHOR]

The ZrN‐SiAlON composite powder was synthesized using low‐grade zircon and bauxite by carbothermal reduction nitridation at first and then ZrN‐SiAlON‐SiC‐C composite refractory were fabricated with the ZrN‐SiAlON powder, SiC particles, and a small amount of Si powder as raw materials and sucrose as the binder. The slag resistance of these composites in O2, N2 and Ar atmosphere was investigated by X‐ray diffraction, scanning electron microscopy, and energy dispersion spectra. The results show that the pores in the inside of ZrN‐SiAlON‐SiC‐C composite refractory were enlarged in oxygen atmosphere due to oxidation, which leads to the decrease in slag resistance. In argon atmosphere, blast furnace slag destroyed the sintered body of zircon, corundum, and cristobalite with the formation of CaZrO3, then infiltrated into and filled the pores inside the refractory to form a dense layer, which hindered the further erosion of the blast furnace slag. In the reducing atmosphere, the interfacial energy of the gas‐liquid phases became larger due to the reactions between blast furnace slag liquid and the gas, resulting in a larger wetting angle which prevented the erosion. [ABSTRACT FROM AUTHOR]

Front Cover: Controlled supramolecular architecture transformation from supramolecular hyperbranched homopolymer to alternating copolymer was successfully achieved by “competitive self‐sorting” assembly. The supramolecular hyperbranched homopolymer was initially constructed by the self‐assembly of dialkylammonium salt (DAAS)‐functionalized pillar[5]arene (MeP5) AB2 monomers. After adding CD2 monomer to the AB2 system, the initial supramolecular hyperbranched homopolymer was disrupted and then reassembled into a new supramolecular hyperbranched alternating copolymer. Further information can be found in article 1600631, by H. Li, X. D. Fan,* X. Min, Y. C. Qian, and W. Tian*. [ABSTRACT FROM AUTHOR]

Hierarchical SAPO-34, MTO, nanosized SAPO-34, SAPO-34 molecular sieves, synthesis methods Keywords: hierarchical SAPO-34; MTO; nanosized SAPO-34; SAPO-34 molecular sieves; synthesis methods EN hierarchical SAPO-34 MTO nanosized SAPO-34 SAPO-34 molecular sieves synthesis methods 1 1 1 02/22/22 20220219 NES 220219 The methanol-to-olefins reaction has received considerable interest owing to its importance in converting abundant resources, such as coal, natural gas and biomass, to widely demanded light olefins. SAPO-34, with a CHA topological structure, has high methanol conversion and excellent selectivity for light olefins. [Extracted from the article]

Introduction: Methylenetetrahydrofolate reductase (MTHFR) is essential in mediating folate metabolism, and thus plays an important role in diabetes and diabetic complications. MTHFR C677T (rs1801133 C>T) polymorphism has been proposed to be linked with type 2 diabetes mellitus (T2DM) susceptibility. However, the conclusions are inconsistent. Therefore, we rechecked their linkage aiming to obtain a more reliable estimation by performing an updated meta‐analysis. Methods: We searched electronic databases PubMed, EMBASE, CNKI, and Wanfang to obtain studies updated to October 2019. Results: After carefully screening, we finally incorporated 68 studies with 10,812 cases and 8,745 controls. The genotype frequency of C677T polymorphism was analyzed pooled to generate odds ratios (ORs) and 95% confidence intervals (CIs). Pooled results presented that MTHFR C677T polymorphism was significantly associated with T2DM under homozygous (OR = 1.64, 95% CI = 1.39–1.94), heterozygous (OR = 1.38, 95% CI = 1.20–1.59), recessive (OR = 1.41, 95% CI = 1.23–1.61), dominant (OR = 1.47, 95% CI = 1.27–1.70), and allele (OR = 1.37, 95% CI = 1.23–1.52) genetic models. Stratified analysis demonstrated that C677T genotype was associated with T2DM in Asian populations, but not Caucasian and African populations. Conclusion: Our results indicated that MTHFR C677T polymorphism confers to T2DM, especially in Asian populations. Much more large‐scale case–control studies are needed to strengthen such conclusion in the future. [ABSTRACT FROM AUTHOR]

In this study, a new strategy to synthesize random and alternating multiblock copolymers (MBCs) by the polycondensation of macromonomers' terminal hydroxyl groups with [CpRu(CH3CN)3]PF6/quinaldic acid as the catalyst is reported, which is often used for the preparation of a variety of biological small molecules via the reaction of allyl ethers. The degrees of hydroxyl functionality (Fn) of the MBCs are assessed by titration, and the presence of hydroxyl on both the ends of MBCs is also confirmed by a chain‐extension experiment of the ring‐opening polymerization of D,L‐lactide. [ABSTRACT FROM AUTHOR]

A New Strategy to Synthesize , -Dihydroxy Multiblock Copolymers via [CpRu(CH3CN)3]PF6/Quinaldic Acid Catalyst B Inside Back Cover b : In article number 1900135, Xiaodong Fan and co-workers report a new strategy to synthesize random and alternating multiblock copolymers (MBCs) via polycondensation of terminal hydroxyl groups in macromolecular monomers. GRAPH. [Extracted from the article]

Hollow structures are often used to relieve the intrinsic strain on metal oxide electrodes in alkali‐ion batteries. Nevertheless, one common drawback is that the large interior space leads to low volumetric energy density and inferior electric conductivity. Here, the von Mises stress distribution on a mesoporous hollow bowl (HB) is simulated via the finite element method, and the vital role of the porous HB structure on strain‐relaxation behavior is confirmed. Then, N‐doped‐C coated mesoporous α‐Fe2O3 HBs are designed and synthesized using a multistep soft/hard‐templating strategy. The material has several advantages: (i) there is space to accommodate strains without sacrificing volumetric energy density, unlike with hollow spheres; (ii) the mesoporous hollow structure shortens ion diffusion lengths and allows for high‐rate induced lithiation reactivation; and (iii) the N‐doped carbon nanolayer can enhance conductivity. As an anode in lithium‐ion batteries, the material exhibits a very high reversible capacity of 1452 mAh g−1 at 0.1 A g−1, excellent cycling stability of 1600 cycles (964 mAh g−1 at 2 A g−1), and outstanding rate performance (609 mAh g−1 at 8 A g−1). Notably, the volumetric specific capacity of composite electrode is 42% greater than that of hollow spheres. When used in potassium‐ion batteries, the material also shows high capacity and cycle stability. [ABSTRACT FROM AUTHOR]