Search

Mechanochromic photonic crystals are attractive due to their force-dependent structural colors; however, showing unrecordable color and unsatisfied performances, which significantly limits their development and expansion toward advanced applications. Here, a thermal-responsive mechanochromic photonic crystal with a multicolor recordability-erasability was fabricated by combining non-close-packing mechanochromic photonic crystals and phase-change materials. Multicolor recordability is realized by pressing thermal-responsive mechanochromic photonic crystals to obtain target colors over the phase-change temperature followed by fixing the target colors and deformed configuration at room temperature. The stable recorded color can be erased and reconfigured by simply heating and similar color-recording procedures respectively due to the thermoswitchable on-off mechanochromism of thermal-responsive mechanochromic photonic crystals along with solid-gel phase transition. These thermal-responsive mechanochromic photonic crystals are ideal rewritable papers for ink-freely achieving multicolor patterns with high resolution, difficult for conventional photonic papers. This work offers a perspective for designing color-recordable/erasable and other stimulus-switchable materials with advanced applications. Mechanochromic photonic crystals are extremely attractive due to their force-dependent structural colors yet are limited by unrecordable color and unsatisfactory performances. Here, the authors report a thermal-responsive mechanochromic photonic crystal with multicolor recordability-erasability. [ABSTRACT FROM AUTHOR]

My comments concern the significant errors in the crystallographic part of the commented paper. The diffraction patterns are erroneously analysed and the final chemical composition is different than those supposed in the paper. There are also some manipulations with data. [ABSTRACT FROM AUTHOR]

SCORE was introduced as a spectral approach to network community detection. Since many networks have severe degree heterogeneity, the ordinary spectral clustering (OSC) approach to community detection may perform unsatisfactorily. SCORE alleviates the effect of degree heterogeneity by introducing a new normalization idea in the spectral domain and makes OSC more effective. SCORE is easy to use and computationally fast. It adapts easily to new directions and sees an increasing interest in practice. In this paper, we review the basics of SCORE, the adaption of SCORE to network mixed membership estimation and topic modeling, and the application of SCORE in real data, including two datasets on the publications of statisticians. We also review the theoretical "ideology" underlying SCORE. We show that in the spectral domain, SCORE converts a simplicial cone to a simplex and provides a simple and direct link between the simplex and network memberships. SCORE attains an exponential rate and a sharp phase transition in community detection, and achieves optimal rates in mixed membership estimation and topic modeling. [ABSTRACT FROM AUTHOR]

The small‐signal dielectric and piezoelectric coefficients of paper‐derived sodium potassium niobate, K0.5Na0.5NbO3 (KNN), were compared with those of conventionally prepared samples. Results show similar functional properties of paper‐derived KNN without significantly decreasing the small‐signal piezoelectric coefficient. The structure and microstructure analysis of conventional KNN and paper‐derived KNN did not reveal any significant difference in the crystal structure and grain size. However, the temperature‐dependent inter‐ferroelectric phase transition temperature estimated from the temperature‐dependent dielectric permittivity data revealed a decrease of approximately 18°C for the paper‐derived KNN and is possibly associated with the structural and microstructural defects. This work indicates that optimizing suspension chemistry and sintering conditions will be critical to enhance the functional response of paper‐derived KNN further. Moreover, paper‐derived ceramic processing, a novel and cost‐effective additive manufacturing technology, can be potentially used to fabricate other electroceramics with a wide range of porosities and sizes as well as complex geometries and multilayer structures. [ABSTRACT FROM AUTHOR]

The text is an introduction to the selected papers from the HES-2023 conference, which focuses on the application of electromagnetic fields for materials processing. The conference was postponed by a year due to the pandemic and the war in Ukraine. The main developments in electroheat involve a multi-physics approach to modeling and simulation, with a focus on coupling different physical domains. The use of AI-based methods, such as digital twins and machine learning, in electrothermal systems is a current topic of research. The conference also covered topics such as induction heating, induction hardening, and inverse problems in induction heating. Overall, 52 papers were presented at the conference, and the 10 selected papers cover the main topics discussed. [Extracted from the article]

Thermal printing technology requires a color developer to activate the dye under the action of heat. Bisphenol A (BPA) has traditionally been used for this purpose, although it has increasingly been replaced by bisphenol S (BPS) in recent years. Due to concerns regarding their toxicity, the Swiss authorities have banned both BPA and BPS from thermal papers since 2020. The impact of this regulatory decision was evaluated during 3 monitoring campaigns: in 2013–2014, 2019 and 2021. They were used to describe the starting point, the transition phase, and the status after entry into force of the ban, respectively. Whereas the use of BPA as color developer dropped from 82.2% in 2013/14 to 10.8% in 2021, the fraction of BPS-based thermal paper rose from 3.1% to 19.1% during the same period, despite being banned. However, Pergafast® 201 (PF201) is now the main color developer in thermal paper in Switzerland, with an occurrence of 60.3%. Other alternatives such as D-8, TGSA, PPSMU, NKK-1304, BPS-MAE, D-90 and Blue4est® have only been marginally detected. This study demonstrates the efficiency of the regulatory measure and the feasibility to substitute BPA in thermal papers with less-toxic alternatives. [Display omitted] • Swiss authorities banned BPA and BPS from thermal papers in 2020. • Whereas BPA use dropped drastically, BPS increased slightly despite its ban. • PF201 is clearly the most frequent color developer currently in Switzerland. • D-8, TGSA, PPSMU, NKK-1304, BPS-MAE, D-90 and Blue4est® were marginally detected. [ABSTRACT FROM AUTHOR]

Hydrophobic paper decorated Ag nanoparticles (NPs) with a uniform distribution was fabricated in an oil-paper-aqueous triphasic system via a facile in situ interfacial reduction approach. Interestingly, the Ag NPs formed at the paper/aqueous interface could migrate to the oil/paper interface. Moreover, these Ag NPs would not continue to migrate away the paper surface into the oil phase but was completely confined in the solid paper matrix. This phase confinement of migrated Ag NPs in the paper matrix creates abundant 3D hot spots for plasmonic enhancement. The obtained Ag-loaded paper exhibits an excellent SERS activity, reliable reproducibility and autofluorescence suppression effect, which enabling it as a promising platform for qualitative and quantitative SERS study. Due to its condensation effect, the hydrophobic paper surface can be used as a concentrator to enrich water-soluble analytes over the SERS active domains for highly sensitive detection (10 −9 mol/L −1 ). Furthermore, the Ag-loaded paper combined with the feature of chromatography and plamon-enhanced optical signals possesses ability to perform synchronous separation and surface-enhanced Raman scattering (SERS) detection of complex samples. [ABSTRACT FROM AUTHOR]

The development of sodium-ion batteries for large-scale applications requires the synthesis of electrode materials with high capacity, high initial Coulombic efficiency (ICE), high rate performance, long cycle life, and low cost. A rational design of freestanding anode materials is reported for sodium-ion batteries, consisting of molybdenum disulfide (MoS2) nanosheets aligned vertically on carbon paper derived from paper towel. The hierarchical structure enables sufficient electrode/electrolyte interaction and fast electron transportation. Meanwhile, the unique architecture can minimize the excessive interface between carbon and electrolyte, enabling high ICE. The as-prepared MoS2@carbon paper composites as freestanding electrodes for sodium-ion batteries can liberate the traditional electrode manufacturing procedure, thereby reducing the cost of sodium-ion batteries. The freestanding MoS2@carbon paper electrode exhibits a high reversible capacity, high ICE, good cycling performance, and excellent rate capability. By exploiting in situ Raman spectroscopy, the reversibility of the phase transition from 2H-MoS2 to 1T-MoS2 is observed during the sodium-ion intercalation/deintercalation process. This work is expected to inspire the development of advanced electrode materials for high-performance sodium-ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five series of rod-like liquid crystals containing cyanostilbene and different terminal atoms were constructed. • Different terminal atoms and chain length induced mesogenic transition between smectic A phase and nematic phase. • Increasing temperature induced fluorescence quenching. • The terminal halogen atoms induced different AIE and mechanochromism behaviors. Five series of cyanostilbene-based rod-like liquid crystals containing one different terminal atom (H, F, Cl, Br and I) at one end and one terminal aliphatic chain with different numbers of carbon atoms at the other end were reported by Suzuki coupling and Knoevenagel reactions. The influence of terminal halogen atoms and terminal chain length on the self-assembly, AIE behavior, temperature-dependent emission and mechanochromism behavior was explored by POM, DSC, XRD, SEM, absorption spectra and emission spectra. All the compounds are enantiotropic liquid crystals. The lowest non-halogen substituted homologue exhibited solo N phase, but the higher non-halogen substituted homologues exhibited mesogenic transition from SmA phase to N phase upon rising temperature. All the lowest halogen substituted homologues exhibited mesogenic transition from SmA phase to N phase upon rising temperature and all the higher homologues only exhibited SmA. The distinct mesogenic phase transition could be attributed to the intermolecular interaction produced by terminal halogen and the rigidity of the terminal aliphatic chain. All the non-halogen substituted compounds and halogen substituted compounds with smaller terminal halogen atom (F, Cl and Br atom) exhibited AIE behaviors, whereas the iodinated compounds exhibited extremely weak emission in solution and aggregated states due to the heavy atoms effect. These compounds also exhibited distinct solid-state emission with blue or cyan fluorescence, which could be quenched by increasing temperature. The reversible mechanochromism behavior was also achieved in all the compounds. The mechanical force induced quench in emission in non-halogen substituted compounds and halogen substituted compounds with smaller terminal halogen atom (F, Cl and Br atom), whereas enhancement in iodinated compounds. The reversible mechanochromism behavior endowed these compounds with potential applications in rewritable paper and anti-counterfeiting. The interesting properties in these liquid crystals would be attributed to the balance of the halogen-halogen interactions, heavy atom effect, steric-hindrance effect and chain length. These investigations would be helpful to understand the relationship between chemical structures and properties. [ABSTRACT FROM AUTHOR]

A facile and low-cost superhydrophobic nanocomposite coating on paper surface was fabricated through one-step simply spraying dispersion, using hydrophobic silica nanoparticles as a filter (SiNPs) and polyvinylidene fluoride (PVDF) as a film-forming material. Hydrophobic SiNPs were fabricated via co-hydropholysis and condensation of TEOS and long-chain alkyl silane based on a simple sol-gel process, and the surface chemical structure of SiNPs was characterized by Fourier transform infrared (FTIR) spectra. The wettability and morphology of the coating surface were measured by contact angle (CA) measurement and scanning electron microscope, respectively. The influence of the mass ratio of hydrophobic SiNPs to PVDF (M(SiNPs:PVDF)) on the superhydrophobicity of paper surface was studied. The results showed that when M(SiNPs:PVDF) was 3:1, the water CA was 156.0 ± 1.0° for the nanocomposite coating with micro/nano-hierarchical structure on paper surface. Further, such superhydrophobic nanocomposite coatings on paper surface showed little adhesive property with water. In addition, the prepared superhydrophobic nanocomposite coating could be applied in other substrates, such as wood, aluminum sheet, stainless steel, polytetrafluoroethylene (PTFE), etc. [ABSTRACT FROM PUBLISHER]

My comments concern the severe errors in the crystallographic part of the commented paper. The correct formula is proposed to be Bi1–xYxFeO3 ('Bi0.85Y0.15FeO3') instead of BiFe0.85Y0.15O3. It is found that the studied sample is bi-phasic with nearly equal amounts of BiFeO3:Y and Bi25FeO39:Y. The actual composition of the studied crystals is not known. Moreover, the type of unit cell is not correct. [ABSTRACT FROM AUTHOR]

Of course, the paper complements the SEM imaging, which is intrinsic to the FIB, with imaging and diffraction in the TEM. The paper does also have a SharedIt link like all articles in JMS (https://rdcu.be/cWW0L) so it can be widely and immediately shared with readers; all papers published in JMS are free-to-read using the SharedIt link from the moment they appear online with their permanent DOI. The cover for the November 2022 issues of the Journal of Materials Science comes from the paper by Tunes et al. which appeared in issue #35 from September 2022 [[1]]. [Extracted from the article]

Herein, we report high electrocatalytic activity of monoclinic VO2 (M1 phase) for the oxygen evolution reaction (OER) for the first time. The single-phase VO2 (M1) nanoparticles are prepared in the form of uniformly covering the surface of individual carbon fibers constituting a carbon fiber paper (CFP). The VO2 nanoparticles reveal the metal-insulator phase transition at ca. 65 °C (heating) and 62 °C (cooling) with low thermal hysteresis, indicating a high concentration of structural defect which is considered a grain boundary among VO2 nanoparticles with some particle coalescence. Consequently, the VO2/CFP shows a high electrocatalytic OER activity with the lowest η10 (350 mV) and Tafel slope (46 mV/dec) values in a 1 M aqueous solution of KOH as compared to those of the vacuum annealed V2O5 and the hydrothermally grown VO2 (M1), α-V2O5, and γ′-V2O5. The catalytically active site is considered V4+ components and V4+/5+ redox couples in VO2. The oxidation state of V4+ is revealed to be more favorable to the OER catalysis compared to that of V5+ in vanadium oxide through comparative studies. Furthermore, the amount of V5+ component is found to be increased on the surface of VO2 catalyst during the OER, giving rise to the performance degradation. This work suggests V4+ and its redox couple as a novel active component for the OER in metal-oxide electrocatalysts. [ABSTRACT FROM AUTHOR]

Developing a flexible nano-composite material which is not only impermeable to low-polar oil, but also has the ability of daytime radiation cooling, remains a huge challenge for both academia and industry. By modifying the fiber network of the dust-free paper using nano-ZnO particles (ZnO-DF), we strategically designed and demonstrated dual capabilities of superhydrophilicity/superoleophobicity and daytime radiant cooling for the flexible cellulose nano-composite simultaneously. A superior surface with superhydrophilic/superoleophobic (oil contact angle up to 159° and water contact angle down to 0°) was attained by regulation of surface energy components and roughness. Furthermore, the materials revealed outstanding corrosion and mechanical damage resistance, 152,788 L m−2 h−1 high permeation flux and >99.2% continuous and efficient oil-water separation performance. In addition, a cooling effect of about 5.6 °C of ZnO-DF paper could be achieved by cooperative function of both radiative cooling and sweat evaporation. It is expected that the ZnO-DF paper is promising for the thermal management of wearable products integrated with passive radiant cooling, phase change cooling (e.g., sweat evaporation) and large-scale industrial oil-water separation. [Display omitted] • A novel and stable flexible cellulose "ZnO-DF paper" nanocomposites were fabricated. • Nanocomposites have multi-functions covering superhydrophilic/superoleophobic and passive radiant cooling. • ◆Cetane-water mixture separation efficiency is up to 99.2%, and the extremely high water permeation flux up to 152,788 L m−2 h−1. • 5.6 °C of moist ZnO-DF paper could be achieved by cooperative function of both radiative cooling and sweat evaporation. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction provides a potential means for synthesizing value-added chemicals over the near equilibrium potential regime, i.e., formate production on Pd-based catalysts. However, the activity of Pd catalysts has been largely plagued by the potential-depended deactivation pathways (e.g., α-PdH to β-PdH phase transition, CO poisoning), limiting the formate production to a narrow potential window of 0 V to -0.25 V vs. reversible hydrogen electrode (RHE). Herein, we discovered that the Pd surface capped with polyvinylpyrrolidone (PVP) ligand exhibits effective resistance to the potential-depended deactivations and can catalyze formate production at a much extended potential window (beyond -0.7 V vs. RHE) with significantly improved activity (~14-times enhancement at -0.4 V vs. RHE) compared to that of the pristine Pd surface. Combined results from physical and electrochemical characterizations, kinetic analysis, and first-principle simulations suggest that the PVP capping ligand can effectively stabilize the high-valence-state Pd species (Pdδ+) resulted from the catalyst synthesis and pretreatments, and these Pdβ+ species are responsible for the inhibited phase transition from α-PdH to α-PdH, and the suppression of CO and H2 formation. The present study confers a desired catalyst design principle, introducing positive charges into Pd-based electrocatalyst to enable efficient and stable CO2 to formate conversion. [ABSTRACT FROM AUTHOR]

An approach of implementing X-bar and R control charts as a statistical control tool to monitor the changes in the melting profile of fresh and stored flaxseed oils by differential scanning calorimetry (DSC) was used. Phase transition melting profiles were collected after 0, 2, 4, and 6 months of storing flaxseed oils, originating from five different cultivars. Four peaks at around −36, −30, −25, and −12 °C were identified using the deconvolution analysis procedure, which enabled the data to be collected at peak temperature (T), peak height (h), the peak area (A), and the percentages of the area (P A), as well as the ratio calculated from these parameters. Control charts obtained for the second peak of the melting profile showed a significant decrease of peak height (h2) from 0.50 to 0.39 W/g and the percentage of the area (P A2) from 50 to 38%, within the storage time (p ≤ 0.05); thus, they were considered to be indicators of oil deterioration. Strong negative correlations of the unstable parameters of DSC with chemical indicators of the oils' oxidative stability (PV, p-AV, TOTOX) were found. For DSC parameters, related to the first peak (h1, A1) and the third peak (h3, A3), changes were statistically not significant within storage (p > 0.05); thus, they can be used as markers of flaxseed oil authenticity. The study demonstrated that X-bar and R control charts could effectively monitor changes in the specific peaks and calculated ratios from the DSC melting profile of fresh and stored flaxseed oils, serving as reliable indicators of oil deterioration. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to increase the thermal resistance of a cellulose substrate, using films (a mixture of corundum-phase aluminum oxide, α-Al2O3, and a PVA solution). The corundum phase, which was chosen due to its high thermal resistance, was obtained using an adaptation of Pechini‘s polymeric precursor method. A polyvinyl alcohol (PVA) solution was used as a medium for mixing the oxide for subsequent deposition on a paper substrate. The materials were characterized by X-ray diffraction (XRD) and field emission gun scanning electron microscopy (FEG-SEM) coupled with energy dispersive X-ray spectrometry (EDS). The thermal behavior of the material was investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC). The EDS results indicate that all the samples with deposited α-phase aluminum oxide contain the chemical elements (Al and O) originating from the α-phase, while the surface analysis indicated that the paper substrates were completely coated with the films. The TG and DSC analyses of the thermal resistance of the film-coated substrate indicate that it was impossible to increase the thermal resistance of the paper substrate because the events that occurred (decomposition of cellulose and pyrolysis of lignin, hemicellulose and PVA) took place in the same temperature range, as has been reported in the literature for samples of the paper substrate without deposited film. [Copyright &y& Elsevier]

Utilizing the phase transition principle of VO2, this paper presents a tunable ultra-wideband terahertz perfect absorption device with simple structure and tunability. The proposed broadband terahertz perfect absorption device is a three-layer structure with a metal reflective layer, a silicon dioxide dielectric layer and a VO2 layer from bottom to top. It was found that the terahertz perfect absorption device's absorption could be dynamically adjusted from 1.2% to 99.9% when changing from an insulated to a metallic state. With the VO2 in the metallic state, the terahertz perfect absorption device has an absorption efficiency of more than 90% in 4.00 to 10.08 THz's ultra-broadband range and near-perfect absorption is achieved in the ranges of 4.71 THz to 5.16 THz and 7.74 THz to 8.06 THz. To explain the working principle of this terahertz perfect absorption device, this paper utilizes wave interference's principle, theory of impedance matching and electric field analysis. Compared to previously reported terahertz metamaterial devices, the vanadium dioxide device proposed in this paper is significantly optimized in terms of tunable range and absorption bandwidth. In addition, the terahertz perfect absorption device is polarization insensitive and maintains good absorptivity over a wide-angle incidence range. This tunable ultra-wideband terahertz perfect absorption device could have applications in the fields of modulation, stealth devices, and thermal emission devices. [ABSTRACT FROM AUTHOR]

We discuss microscopic mechanisms of complex network growth, with the special emphasis of how these mechanisms can be evaluated from the measurements on real networks. As an example we consider the network of citations to scientific papers. Contrary to common belief that its growth is determined by the linear preferential attachment, our microscopic measurements show that it is driven by the nonlinear autocatalytic growth. This invalidates the scale-free hypothesis for the citation network. The nonlinearity is responsible for a dramatic dynamical phase transition: while the citation lifetime of majority of papers is 6-10 years, the highly-cited papers have practically infinite lifetime. [ABSTRACT FROM AUTHOR]

A recent paper [1] presents a high-resolution, high-temperature version of the Nitrogen Dioxide Spectroscopic Databank called NDSD-1000. The NDSD-1000 database contains line parameters (positions, intensities, self- and air-broadening coefficients, exponents of the temperature dependence of self- and air-broadening coefficients) for numerous cold and hot bands of the 14 N 16 O 2 isotopomer of nitrogen dioxide. The parameters used for the line positions and intensities calculation were generated through a global modeling of experimental data collected in the literature within the framework of the method of effective operators. However, the form of the effective dipole moment operator used to compute the NO 2 line intensities in the NDSD-1000 database differs from the classical one used for line intensities calculation in the NO 2 infrared literature [12]. Using Fourier transform spectra recorded at high resolution in the 6.3 µm region, it is shown here, that the NDSD-1000 formulation is incorrect since the computed intensities do not account properly for the (Int(+)/Int(−)) intensity ratio between the (+) (J = N+ 1/2) and (−) (J = N−1/2) electron – spin rotation subcomponents of the computed vibration rotation transitions. On the other hand, in the HITRAN or GEISA spectroscopic databases, the NO 2 line intensities were computed using the classical theoretical approach, and it is shown here that these data lead to a significant better agreement between the observed and calculated spectra. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. It includes a cover image and an inside cover image, both with accompanying articles. The document also lists several papers that are featured in the journal, covering topics such as crystal structures, coordination polymers, and the synthesis of various materials. The journal is published by The Royal Society of Chemistry, a leading chemistry community. [Extracted from the article]

Many results have been obtained when studying scientific papers citations databases in a network perspective. Articles can be ranked according to their current in-degree and their future popularity or citation counts can even be predicted. The dynamical properties of such networks and the observation of the time evolution of their nodes started more recently. This work adopts an evolutionary perspective and proposes an original algorithm for the construction of genealogical trees of scientific papers on the basis of their citation count evolution in time. The fitness of a paper now amounts to its in-degree growing trend and a “dying” paper will suddenly see this trend declining in time. It will give birth and be taken over by some of its most prevalent citing “offspring”. Practically, this might be used to trace the successive published milestones of a research field. [ABSTRACT FROM AUTHOR]

Abstract: Bucky paper (BP) made from vertically aligned carbon nanotubes exhibits a high mechanical strength and flexibility owing to the high aspect ratio of the carbon nanotubes. Such macroscopic material with nanoscopic properties was efficiently used as a catalyst support in the gas-phase desulfurization reaction. The Fe2O3 (3wt.%) supported on BP exhibits superior stability and activity in H2S oxidation to sulphur compared with other catalysts supported on activated charcoal and carbon felt. The high stability of the Fe2O3/BP catalyst was attributed to the presence of a strong active phase-support interaction which prevents the active phase sintering during operation. [Copyright &y& Elsevier]

My comments concern the significant errors in the crystallographic part of the commented paper. [ABSTRACT FROM AUTHOR]

The new analysis of the previously published data on the nanocrystalline CaYTiNbO7:Eu indicates an occurrence of the size-induced structural phase transition like in other nanocrystalline phosphors of pyrochlore structure. [ABSTRACT FROM AUTHOR]

I would like to comment the crystallographic part of the paper by Santosh Kumor Parida and Rama Narayan Prasad Choudhary entitled 'Preparation method and cerium dopant effects on the properties of BaMnO3 single perovskite' and published in 'Phase Transitions' in September 2020 [1]. There are several errors that should be corrected, if possible. [ABSTRACT FROM AUTHOR]

This document is a special issue of the journal "Materials" that focuses on the recent progress in the structure transition, processing, characterization, and applications of metallic materials. The issue includes research papers on various topics such as the development of dispersion-strengthened copper alloys, the characterization of carbide precipitation in steel, the effect of magnetic fields on aluminum bronze, and the enhancement of impact toughness in cast iron through heat treatment. The issue aims to provide comprehensive and up-to-date information for researchers, engineers, and industry experts in the field of metallic materials. [Extracted from the article]

Kirigami, the ancient paper art of cutting, has recently emerged as a new approach to construct metamaterials with novel properties imparted by cuts. However, most studies are limited to thin sheets‐based 2D kirigami metamaterials with specific forms and limited reconfigurability due to planar connection constraints of cut units. Here, 3D modular kirigami is introduced by cutting bulk materials into spatially closed‐loop connected cut cubes to construct a new class of 3D kirigami metamaterials. The module is transformable with multiple degrees of freedom that can transform into versatile distinct daughter building blocks. Their conformable assembly creates a wealth of reconfigurable and disassemblable metamaterials with diverse structures and unique properties, including reconfigurable 1D column‐like materials, 2D lattice‐like metamaterials with phase transition of chirality, as well as 3D frustration‐free multilayered metamaterials with 3D auxetic behaviors and programmable deformation modes. This study largely expands the design space of kirigami metamaterials from 2D to 3D. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. The list includes various papers on topics such as molecular packing characteristics, crystal structures, photocatalytic activity, crystal growth, and more. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document also mentions approved training courses offered by the society. [Extracted from the article]

This document discusses the importance of lubricating oil and grease in reducing friction and wear in mechanical parts. It highlights the role of additives in enhancing the performance of lubricants and grease, such as improving wear resistance and thermal stability. The document includes 11 papers that cover various topics related to lubricants and grease, including the use of additives like layered double hydroxide and molybdenum disulphide, carbon-based nanomaterials, fullerenes, graphene, and WS2 nanoparticles. The papers explore the effects of these additives on the tribological properties of lubricants and grease, such as friction reduction and improved oxidation resistance. The document also discusses the synthesis and design of lubricant additives using computational simulations and quantitative structure-property relationship models. Overall, the document provides valuable insights into the research and applications of additives for lubricating oil and grease. [Extracted from the article]

The efficiency and economy of an ASHP (air source heat pump) can be significantly improved in a cold area by combining it with a TESU (thermal energy storage unit). The work of looking for a phase change material with a suitable temperature range, a large thermal capacity, and high conductivity has been always on the road. This paper prepared 10 CPCMs (composites of a phase change material) by using the vacuum adsorption method, which consists of LA (lauric acid) as the phase change material and EG (expanded graphite) as the skeleton matrix for its high thermal conductivity and porous characteristics. By characterizing and analyzing their basic properties, surface morp\hology, and stability, a suitable CPCM for the TESU coupled with the ASHP heating system is found. The leakage experiment results show that the maximum effective content of LA absorbed in 100-mesh EG of a CPCM is 80%, and that in 200-mesh EG, it is 90%. Among 10 CPCMs, CPCM3, with a mass ratio of LA:EG/8:2, is considered the more satisfactory one for the TESU proposed by this paper, because its performance shows good stability, its phase transition temperature is 40.98–41.94 °C, its latent heat is 164.34–168.28 kJ/kg, and especially, its thermal conductivity is 8.15–8.33 W/(m·K). This paper will be followed by performance research on TESUs coupled with ASHP heating systems. [ABSTRACT FROM AUTHOR]

We present a metapopulation dynamic model for the diffusively-coupled rock-paper-scissors (RPS) game with mutation in scale-free hierarchical networks. We investigate how the RPS game changes by mutation in scale-free networks. Only the mutation from rock to scissors (R-to-S) occurs with rate μ. In the network, a node represents a patch where the RPS game is performed. RPS individuals migrate among nodes by diffusion. The dynamics are represented by the reaction-diffusion equations with the recursion formula. We study where and how species coexist or go extinct in the scale-free network. We numerically obtained the solutions for the metapopulation dynamics and derived the transition points. The results show that, with increasing mutation rate μ , the extinction of P species occurs and then the extinction of R species occurs, and finally only S species survives. Thus, the first and second dynamical phase transitions occur in the scale-free hierarchical network. We also show that the scaling law holds for the population dynamics which suggests that the transition points approach zero in the limit of infinite size. [ABSTRACT FROM AUTHOR]

Abstract: Carbon paper is commonly used as the gas diffusion layer (GDL) in polymer electrolyte membrane (PEM) fuel cells as it exhibits high chemical and mechanical durability. This diffusion medium is also anisotropic, which directly affects its transport properties and specifically the thermal conductivity. In this study, the in-plane thermal conductivity of the carbon paper GDL was determined using thermal diffusivity measurements for a temperature range from −20 to +120°C and four Teflon loadings (0, 5, 20 and 50wt.%). It is important to understand the effect of temperature on the thermal conductivity since PEM fuel cells are designed to operate under various temperatures depending on the application of use. Further, Teflon is used to change the hydrophobic properties of the carbon paper GDL with 20wt.% as the most widely used percentage. In this study, the Teflon loadings were chosen to gain a comprehensive understanding of the thermal resistance due to Teflon. In this study, a quasi-steady method was used to measure the thermal properties of the carbon paper; hence, the phase transformation in the presence of PTFE was investigated. The thermal conductivity decreases with an increase in temperature for all samples. The addition of as little as 5wt.% Teflon resulted in high thermal resistance decreasing the overall thermal conductivity of the sample. Further addition of Teflon did not have major effects on the thermal conductivity. For all treated samples, the thermal conductivity lies in the range of 10.1–14.7W/mK. Finally, empirical relations for the thermal diffusivity and conductivity with temperature were deduced. [Copyright &y& Elsevier]

The New Journal of Chemistry is a publication that features articles and papers on various topics in chemistry. The current issue includes papers on lithium-sulfur batteries, graphene, and carbon nanotubes, among others. The journal is published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. The papers provide valuable insights and findings in their respective fields of research, covering topics such as compound synthesis, crystal structures, magnetic behavior, and the development of new materials for applications like photocatalysis and electrocatalysis. The journal also offers professional recognition and development opportunities for scientists. [Extracted from the article]

Abstract: A new tar destruction technology has been developed by integrating in-situ catalytic gasification and a hot-gas cleaning system in the catalytic gasification of paper-reject sludge. Experimental results indicated that the tar yield in syngas decreased significantly from 13.64 to 10.76 g/m3, when increasing the zeolite addition during in-situ catalytic gasification. When the syngas passed through the hot-gas cleaning system, the tar concentration measured from downstream was approximately 0.22 g/m3. The hot-gas cleaning system used in this research seems to have played a significant role in reducing tar concentration of the syngas. The major tar speciation identified after hot-gas cleaning system was 1-ring or 2-ring hydrocarbons, which included benzene, toluene, xylene, styrene and naphthalene. In summary, the energy yield efficiency of syngas will be enhanced due to the tar reduction and transformation. The syngas seems to be appropriate to use as a fuel in gas engines for electricity generation. [Copyright &y& Elsevier]