Simple Composition Research Articles

Controllable Deformation Modulated Multi‐Functionality for Phase‐Gradient Metamaterials

AbstractTunable metamaterials offer versatile approaches to achieve the dynamic manipulation of electromagnetic waves with various dimensionality. Recently, mechanical approaches have been extensively employed to construct reconfigurable metamaterials with simple composition and superior mechanical characteristics. Mechanical modulation methods in phase‐gradient metamaterials are even more worthy of being investigated to facilitate valuable applications. Here, an in‐plane rotational deformation principle is proposed to assist the structural design of reconfigurable phase‐gradient metamaterials by integrating split ring resonators (SRRs) on the hyperelastic kirigami substrate. The orientations and split angles of SRRs are explored to manipulate the amplitudes and phases of cross‐polarized transmittance under x‐polarized incidence, respectively. The tensile strains dramatically modulate the amplitudes yet not the gradient phase. As proof‐of‐concept, a reconfigurable metalens is elaborately designed to realize tunable focus location and number by regulating the transmittance amplitudes of meta‐atoms via stretching the kirigami substrate. Furthermore, a holographic metamaterial is developed to perform dynamic hologram on the imaging plane under the strain 0% and 40%. The proposed mechanical deformation principle offers a promising platform for dynamic manipulation of the wavefront and may promote the conformal and flexible designs in certain cases and enlarge the potential applications of meta‐devices in imaging and information encryption.

An Unexpected Driving Force for Lipid Order Appears in Asymmetric Lipid Bilayers.

An ordered phase in one leaflet of an asymmetric bilayer can induce a precisely superimposed induced order domain in the apposed leaflet. Order is induced in such simple lipid compositions as dioleoylphosphatidylcholine/cholesterol (DOPC)/chol) which is expected to be a uniform and disordered lipid mixture. Dye partitioning can be used to label and identify coexisting liquid-disordered (Ld), liquid-ordered (Lo), or gel-ordered (Lβ) molecules in a phase-separated leaflet. In the other leaflet of an asymmetric bilayer, dye partitioning also labels and identifies any induced order domains created by an Lo or gel phase domain in the apposed leaflet as well as the state of disorder of the lipid surrounding the induced ordered region. We explore a molecular level mechanism by which a disorder-prone uniform mixture of DOPC/chol = 0.8/0.2 would spontaneously separate into ordered regions coexisting with disordered regions. A redistribution of cholesterol seems to take place in the regions apposed to the ordered phase. The precision of the superposition of Lo or gel domains with their induced order domains implies a strong energy penalty that would be incurred if order/disorder interfaces were to form at the bilayer midplane. We conclude that the energy penalty for Lo/Ld or gel/Ld contact in the bilayer midplane is sufficient to drive disorderly DOPC/chol into an ordered state that reduces unfavorable order-disorder contacts at the bilayer midplane interface.

Exploring the tunability of lead free Ba0.5Sn0.5TiO3 to mimic PbTiO3

Can a material be designed and engineered to use as a replacement for an environmentally unfriendly material? In the specific context of lead titanates, the quest for finding such material replacements is ongoing, beginning from lead free alternatives with simple perovskite compositions, extending to hybrid and double perovskite compositions. In this work, we have demonstrated through ab initio density functional theory investigations the tunability of multiple properties of a simple perovskite Ba0.5Sn0.5TiO3 to mimic that of PbTiO3. Our results show that A-site Sn enhances the polarization of Ba0.5Sn0.5TiO3 closer to that of PbTiO3 and tunes its pressure dependent polarization behavior to become similar to that of PbTiO3 and dissimilar to that of BaTiO3 by reorienting the displacements profiles of A, B site and O atoms to become like that of their counterparts in PbTiO3. Compressive pressures facilitate transition from indirect to direct bandgap, increase the mobility of charge carriers and lead to stronger exciton binding in Ba0.5Sn0.5TiO3 opening up its use for optoelectronics. Ba0.5Sn0.5TiO3 has an early onset of absorption and its absorption spectra in UV range is qualitatively similar to PbTiO3 albeit with reduced absorption peak heights and broadening. The absorption spectra of Ba0.5Sn0.5TiO3 can be modified via application of strains and peak absorption heights can be changed to become similar to that of PbTiO3. We also demonstrate that the dielectric constant as well as refractive index of Ba0.5Sn0.5TiO3 can be modulated to increase (decrease) by applying compressive (tensile) strains. The study of mechanical properties demonstrates that Ba0.5Sn0.5TiO3 is more ductile and is mechanically stable even under higher compressive strains making it excitingly attractive for device applications over other lead-free alternatives that are known to display poor stabilities. These comprehensive investigations demonstrate for the first time that all the physical properties of Ba0.5Sn0.5TiO3 can be tuned as desired for a chosen device application making it a competitive and green replacement to lead titanates.

THE INFLUENCE OF EUROPEAN ART ON CHINESE OPERA CULTURE

The article examines the influence of European culture on the origin and development of Beijing opera, focusing on the penetration and assimilation of European opera's characteristic features into Chinese musical culture. It systematically analyzes these innovations within the historical context, elucidating their role and position in the broader Chinese cultural and historical processes. The study reveals that the primary avenue for introducing European musical canons was through school songs, which, due to their simple composition and ease of performance, served as the basis for incorporating structured European approaches into Chinese music. It notes that the creation of the first officially recognized Chinese opera, “Grey-hair Girl”, followed the emergence of Children's Operas, which exhibited elements of Europeanization while retaining their melodic structure. The conclusions highlight that the development of the European experience within the opera genre unfolded in tandem with the evolution of compositional and dramatic patterns derived from Western opera. However, on a musical and stylistic level, Chinese composers remained rooted in the national tradition, endeavoring to achieve varying degrees of successful fusion between Western form and national content. It was only towards the latter part of the 20th century that a harmonious symbiosis began to emerge, integrating the organizational aspects of opera from the European experience with Chinese identity at different levels.

Superconductivity above 30K Achieved in Dense Scandium

Superconductivity is one of most intriguing quantum phenomena, and the quest for elemental superconductors with high critical temperature (T c) is of great scientific significance due to their relatively simple material composition and the underlying mechanism. Here we report the experimental discovery of densely compressed scandium (Sc) becoming the first elemental superconductor with T c breaking into 30 K range, which is comparable to the T c values of the classic La–Ba–Cu–O or LaFeAsO superconductors. Our results show that of Sc increases from ∼ 3 K at around 43 GPa to ∼ 32 K at about 283 GPa ( K), which is well above liquid neon temperature. Interestingly, measured T c shows no sign of saturation up to the maximum pressure achieved in our experiments, indicating that T c may be even higher upon further compression.

Gas Analysis of Large-Format Automotive Lithium-Ion Battery Cells during Formation

Due to the decision by the European Union to stop sales of combustion-based vehicles after 2035, all car manufacturers are in search to close this gap with alternative solutions. As Lithium-Ion batteries (LIBs) are already an integral part of our everyday life, battery based electric vehicles (BEVs) are expected to be one possible alternative for the individual mobility of tomorrow. Therefore, all original equipment manufacturers (OEMs) who want to produce their own battery cells must deal with many challenges as the LIB is the most expensive single component used in EVs. Reducing costs of LIB production is making EVs more affordable and even more sustainable. One major production-related factor is the dwell-time under dry-room conditions as its disproportionately increases the overall production costs. Dry-Room conditions can´t be avoided as materials like the electrolyte and active material rely on water-free handling conditions [2-3, 5].Battery cells are typically assembled in a dry state. Cells are then filled with electrolyte and a so-called precharge step is performed. During this, the solid-electrolyte interface (SEI) is formed on the negative electrode when the electrolyte is partially reduced. The formation process results in a significant gas evolution, where typical gasses like CO, CO2, H2, O2, C2H4 can be formed [1, 4, 5]. After main gas evolution, the cells can be sealed and transported into normal atmosphere, where further charging and evaluation protocols are performed. In order to understand the voltage-related gas evolution during first charging, new analytical methods are needed. The hyphenation of electrochemical cycling and mass spectrometry to so-called Online-Electrochemical Mass Spectrometry (OEMS) is a powerful technique to investigate the gas evolution inside LIBs.In this project the development of OEMS for large-format prismatic LIBs will be outlined. The feasibility of studying battery cell formation reactions and the influence of typical parameters, like temperature or charging rate onto the gassing rate will be discussed. The obtained experiments are designed to give new insights into the gas formation during first charge and how the results compare in size to already well described model-cell OEMS-experiments [2, 3]. The cells are based on a graphite / NMC811 system with ethylene carbonate (EC) and ethyl methyl carbonate (EMC) 5/7 w% (LP57-electrolyte). The cells are produced by our BMW inhouse prototype production line and provide a clear as simple composition of all components. In contrast, commercially available LIBs differ in many aspects, e.g., containing a complex mixture of different volatile organic carbonates as well as quite often unknown additives, which may complicate the analysis [4]. The inhouse production also allows a unique integration of a commercially available Swagelok fitting in the lid of the LIB.

Molecular Structure of Gaseous Oxopivalate Co(II): Electronic States of Various Multiplicities.

Synchronous electron diffraction/mass spectrometry was used to study the composition and structure of molecular forms existing in a saturated vapor of cobalt(II) oxopivalate at T = 410 K. It was found that monomeric complexes Co4O(piv)6 dominate in the vapor. The complex geometry possesses the C3 symmetry with bond lengths Co-Oc = 1.975(5) Å and Co-O = 1.963(5) Å, as well as bond angles Oc-Co-O = 111.8(3)°, Co-Oc-Co = 110.4(6)°, O-Co-O = 107.1(3)° in the central OcCo4 fragment and four OcCoO3 fragments. The presence of an open 3d shell for each Co atom leads to the possibility of the existence of electronic states of the Co4O(piv)6 complex with Multiplicities 1, 3, 5, 7, 9, 11, and 13. For them, the CASSCF and XMCQDPT2 calculations predict similar energies, identical shapes of active orbitals, and geometric parameters, the difference between which is comparable with the error of determination by the electron diffraction experiment. QTAIM and NBO analysis show that the Co-Oc and Co-O bonds can be attributed to ionic (or coordination) bonds with a significant contribution of the covalent component. The high volatility and simple vapor composition make it possible to recommend cobalt (II) oxopivalate as precursors in the preparation of oxide films or coatings in the CVD technologies. The features of the electronic and geometric structure of the Co4O(piv)6 complex allows for the conclude that only a very small change in energy is required for the transition from antiferromagnetically to ferromagnetically coupled Co atoms.

Messenger RNA chromatographic purification: advances and challenges

Messenger RNA (mRNA) technologies have shown great potential in prophylactic vaccines and therapeutic medicines due to their adaptability, rapidity, efficacy, and safety. The purity of mRNA determines the efficacy and safety of mRNA drugs. Though chromatographic technologies are currently employed in mRNA purification, they are facing challenges, mainly arising from the large size, relatively simple chemical composition, instability, and high resemblance of by-products to the target mRNA. In this review, we will first make a comprehensive analysis of physiochemical properties differences between mRNA and proteins, then the major challenges facing in mRNA purification and general considerations are highlighted. A detailed summary of the state-of-arts in mRNA chromatographic purification will be provided, which are mainly classified into physicochemical property-based (size, charge, and hydrophobicity) and chemical structure-based (phosphate backbone, bases, cap structure, and poly A tail) technologies. Efforts in eliminating dsRNA byproducts via post in vitro transcript (IVT) purification and by manipulating the IVT process to reduce the generation of dsRNA are highlighted. Finally, a brief summary of the current status of chromatographic purification of the emerging circular mRNA (circRNA) is provided. We hope this review will provide some useful guidance for the Quality by Design (QbD) of mRNA downstream process development.

Oxidation in Ca/K-1144 iron-based superconductors polycrystalline compounds

Iron-based superconductors (IBSCs) are a class of material under investigation for the development of superconducting wires in the low-temperature-high magnetic fields power application. Among the various families of IBSCs, the 1144 CaKFe4As4 compound is a promising material able to achieve outstanding superconducting properties with a cheap and simple chemical composition. Oxidation, in these compounds, is considered an obstacle for high intergranular critical current density, Jc,GB. A study devoted to the evaluation of oxidation phenomena and their effects on the superconducting properties is thus needed in order to fully understand the involved mechanisms. From the evaluation of polycrystalline samples obtained by a mechanochemically assisted synthesis route, a degradation of the critical temperature and critical currents has been observed concurrently with oxygen accumulation at grain boundaries in open porosities. However, the crystalline structure at an atomic level seems not affected, as well as intragranular superconducting properties assessed by means of calorimetric methods. These results suggest that loss of superconducting properties in Ca/K-1144 compounds following oxidation is significantly associated with the worsening of grain connectivity.

Neural underpinnings of processing combinatorial unstated meaning and the influence of individual cognitive style.

We investigated the neurocognitive mechanisms underlying the processing of combinatorial unstated meaning. Sentences like "Charles jumped for 5 minutes." engender an iterative meaning that is not explicitly stated but enriched by comprehenders beyond simple composition. Comprehending unstated meaning involves meaning contextualization-integrative meaning search in sentential-discourse context. Meanwhile, people differ in how they process information with varying context sensitivity. We hypothesized that unstated meaning processing would vary with individual socio-cognitive propensity indexed by the Autism-Spectrum Quotient (AQ), accompanied by differential cortical engagements. Using functional magnetic resonance imaging, we examined the processing of sentences with unstated iterative meaning in typically-developed individuals and found an engagement of the fronto-parietal network, including the left pars triangularis (L.PT), right intraparietal (R.IPS), and parieto-occipital sulcus (R.POS). We suggest that the L.PT subserves a contextual meaning search, while the R.IPS/POS supports enriching unstated iteration in consideration of event durations and interval lengths. Moreover, the activation level of these regions negatively correlated with AQ. Higher AQ ties to lower L.PT activation, likely reflecting weaker context sensitivity, along with lower IPS activation, likely reflecting weaker computation of events' numerical-temporal specifications. These suggest that the L.PT and R.IPS/POS support the processing of combinatorial unstated meaning, with the activation level modulated by individual cognitive styles.

Applications of DNA tetrahedron nanostructure in cancer diagnosis and anticancer drugs delivery

Abstract DNA nanostructures constructed under the guidance of DNA nanotechnology have developed rapidly for the last two decades, standing at the forefront in the biomedical field. Among them, DNA tetrahedron nanostructure (DTN) has emerged as one of the most representative DNA nanostructures. DTN was easily formed by one-step annealing of four single-stranded DNA. Due to its unique advantages such as simple and stable structural composition, high synthesis efficiency, uniform nanometer size, high programmability, and good biocompatibility, DTN has been widely used in biological detection, biological imaging, drug delivery, and other fields, and shows a great potential. Especially in the detection of cancer-related biomarkers and the delivery of anticancer drugs, nano-platforms based on DTN has achieved great success. In this review, we focus on the applications of DTN in cancer diagnosis and therapy, as well as the challenges and prospects.

MgO-mediated activation of active carbon as an affordable strategy to “in situ” degradation of lindane in contaminated soils

The accumulation in soil landfills of toxic and persistent lindane, widely used as an insecticide, triggers the risk of leaching with the concomitant contamination of surrounding rivers. Thus, viable remediation to eliminate in situ high concentrations of lindane in soil and water becomes an urgent demand. In this line, a simple and cost-effective composite is proposed, including the use of industrial wastes. It includes reductive and non-reductive base-catalyzed strategies to remove lindane in the media. A mixture of magnesium oxide (MgO) and activated carbon (AC) was selected for that purpose. The use of MgO provides a basic pH. In addition, the specific selected MgO forms double-layered hydroxides in water which permits the total adsorption of the main heavy metals in contaminated soils. AC provides adsorption microsites to hold the lindane and a reductive atmosphere that was increased when combined with the MgO. These properties trigger highly efficient remediation of the composite. It permits a complete elimination of lindane in the solution. In soils doped with lindane and heavy metals, it produces a rapid, complete, and stable elimination of lindane and immobilization of the metals. Finally, the composite tested in lindane-highly contaminated soils permits the “in situ” degradation of nearly 70% of the initial lindane. The proposed strategy opens a promising way to face this environmental issue with a simple, cost-effective composite to degrade lindane and fix heavy metals in contaminated soils.

Multifunctional Hollow Porous Fe3O4@N-C Nanocomposites as Anodes of Lithium-Ion Battery, Adsorbents and Surface-Enhanced Raman Scattering Substrates

At present, it is still a challenge to prepare multifunctional composite nanomaterials with simple composition and favorable structure. Here, multifunctional Fe3O4@nitrogen-doped carbon (N-C) nanocomposites with hollow porous core-shell structure and significant electrochemical, adsorption and sensing performances were successfully synthesized through the hydrothermal method, polymer coating, then thermal annealing process in nitrogen (N2) and lastly etching in hydrochloric acid (HCl). The morphologies and properties of the as-obtained Fe3O4@N-C nanocomposites were markedly affected by the etching time of HCl. When the Fe3O4@N-C nanocomposites after etching for 30 min (Fe3O4@N-C-3) were applied as the anodes for lithium-ion batteries (LIBs), the invertible capacity could reach 1772 mA h g−1 after 100 cycles at the current density of 0.2 A g−1, which is much better than that of Fe3O4@N-C nanocomposites etched, respectively, for 15 min and 45 min (948 mA h g−1 and 1127 mA h g−1). Additionally, the hollow porous Fe3O4@N-C-3 nanocomposites also exhibited superior rate capacity (950 mA h g−1 at 0.6 A g−1). The excellent electrochemical properties of Fe3O4@N-C nanocomposites are attributed to their distinctive hollow porous core-shell structure and appropriate N-doped carbon coating, which could provide high-efficiency transmission channels for ions/electrons, improve the structural stability and accommodate the volume variation in the repeated Li insertion/extraction procedure. In addition, the Fe3O4@N-C nanocomposites etched by HCl for different lengths of time, especially Fe3O4@N-C-3 nanocomposites, also show good performance as adsorbents for the removal of the organic dye (methyl orange, MO) and surface-enhanced Raman scattering (SERS) substrates for the determination of a pesticide (thiram). This work provides reference for the design and preparation of multifunctional materials with peculiar pore structure and uncomplicated composition.

Thermal performance analysis and burning questions of refrigerant direct cooling for electric vehicle battery

Refrigerant direct cooling technology has been gaining attention due to its advantages of simple system composition and high cooling efficiency, but its temperature control performance does not have advantages over mature liquid cooling in industrial applications, reasons for which should be discovered. This paper proposes a novel discrete model based on an electro-thermal coupling method and thermal resistance network to analyze the local temperature control performance of refrigerant direct cooling and liquid cooling systems under real operating scenarios with acceptable computing time and accuracy. The results show that the phase change of the refrigerant in the refrigerant direct cooling plate significantly affects the temperature control performance. The vapour-liquid two-phase zone has a high heat transfer capability, which can dissipate heat well and maintain a small temperature difference with the maximum temperature of the battery reduced by 28.3% compared with the liquid cooling system. There is a serious heat transfer deterioration in the superheated gaseous zone, causing a significant increase in the local battery temperature, and the maximum temperature difference is much higher than that in the liquid cooling system. When the refrigerant switches from two-phase to single-phase under 2C charging condition, the heat transfer coefficient reduces by roughly 73.6%, which causes the accompanying battery unit temperature to rise by about 12 ∼ 14 °C. Besides, the low refrigerant temperature will cause a large temperature difference in the vertical direction of the battery, which restricts the application of the refrigerant direct cooling system in practice. When the evaporation pressure increases from 300 kPa to 500 kPa, the temperature difference will decrease from 14.1 °C to 8.8 °C which is a 37.6% reduction. Through an in-depth analysis of the local temperature distribution of battery units, two burning questions were identified which deteriorate the temperature control performance of the refrigerant direct cooling system and results can provide directions for performance improvement.

High compressive plasticity refractory medium entropy alloy fabricated by laser powder bed fusion using elemental blended powders

High plasticity light weight refractory complex concentrated alloys (RCCAs) are the best alternative to replace nickel base alloy. The advantages of additive manufacturing (AM) in the rapid and direct forming of complex structure RCCA parts are beyond the reach of traditional techniques. In this work, a simple composition of refractory metal elementals was carefully designed. The single-phase BCC Nb–40Ti–20Ta refractory alloy was fabricated by laser powder bed fusion (LPBF) using elemental blended powders, it has excellent compression plasticity (e>80%) and strength at both room and high temperatures. The effects of laser parameters and treatment process on microstructure and mechanical properties of the Nb–40Ti–20Ta alloy were investigated. The experimental results show that the density and hardness of the alloy are approximately positively correlated with the laser energy density. The laser parameters have a significant effect on the microstructure. Too low energy density leads to the formation of some unmelted powders, while too high power density results in the transformation of micro-pore into larger keyhole. The laser short action time and too rapid cooling rate of the molten pool induce the micro-segregation in grains. β-phase dendrites are formed from inside to outside while the high melting point Ta acts as the center, and Ti is enriched in the inter-dendrite region. The shapes of grains are divided into two types: columnar and cellular substructures. The single phase BCC Nb–40Ti–20Ta alloy has ultra compressive plasticity whether annealed or not. The results show that the novel alloy prepared by LPBF possesses excellent mechanical properties. This work provides an important progress for the preparation high compressive plasticity RHEAs by LPBF using elemental blended powders.

Microemulsion and microsuspension polymerization of methyl methacrylate in surfactant-free microemulsions (SFME)

HypothesisThis article presents a free-radical polymerization method in a mesostructured system – free of any surfactants, protective colloids, or other auxiliary agents. It is applicable for a large variety of industrially relevant vinylic monomers. The aim of this work is to study the impact of surfactant-free mesostructuring on the polymerization kinetics and the polymer derived. ExperimentsSo-called surfactant-free microemulsions (SFME) were investigated as reaction media with a simple composition comprising water, a hydrotrope (ethanol, n-propanol, isopropanol, tert-butyl alcohol), and the monomer as the reactive oil phase (methyl methacrylate). Polymerization reactions were performed using oil-soluble, thermal- and UV-active initiators (surfactant-free microsuspension polymerization) and water-soluble, redox-active initiators (surfactant-free microemulsion polymerization). Structural analysis of the SFMEs used and the polymerization kinetics were followed by dynamic light scattering (DLS). Dried polymers were analyzed with regard to their conversion yield by mass balance, the corresponding molar masses were determined using gel permeation chromatography (GPC), and the morphology was investigated by light microscopy. FindingsAll alcohols are suitable hydrotropes to form SFMEs, except for ethanol, which forms a molecularly disperse system. We observe significant differences in the polymerization kinetics and the molar masses of the polymers obtained. Ethanol leads to significantly higher molar masses. Within a system, higher concentrations of the other alcohols investigated give rise to less pronounced mesostructuring, lower conversions, and lower average molar masses. It could be demonstrated that the effective concentration of alcohol in the oil-rich pseudophases as well as the repulsive effect of the surfactant-free, alcohol-rich interphases constitute the relevant factors influencing polymerization. Concerning the morphology, the polymers derived range from powder-like polymers in the so-called “pre-Ouzo region” over porous-solid polymers in the bicontinuous region to dense, almost compacted, transparent polymers in unstructured regions, comparable to the findings for surfactant-based systems reported in the literature. Polymerizations in SFME comprise a new intermediate between well-known solution (i.e., molecularly dispersed) and microemulsion respectively microsuspension polymerization processes.

Simultaneously enhanced piezoelectric response and depolarization temperature in BNT-7BT ceramics with simple composition via optimizing sintering temperature

For (Bi0.5Na0.5)TiO3-based ceramics, one of the obstacles limiting their actual application is the incompatibility of a large piezoelectric response d33 with a low depolarization temperature Td. In this work, a high d33 of 186 pC/N and a Td of 133 °C are achieved simultaneously in unmodified 0.93(Bi0.5Na0.5) TiO3–0.07BaTiO3 (BNT-7BT) ceramics only via optimizing sintering temperature. Structural and microstructural analyses show that grain size and relative content of P4bm and R3c phases in BNT-7BT ceramics can be regulated by tuning the sintering temperature (Tsinter = 1100 °C, 1120 °C, 1140 °C, 1160 °C, and 1180 °C). Thus, high sintering temperature is not only able to increase the grain size to promote the domains switching for higher the piezoelectric response, but also to enhance the ratio of R3c/P4bm phase so as to improve ferroelectric-relaxor transition temperature that defer the depolarization. Hence, the present work provides a simple and effective method for optimizing the piezoelectric properties of (Bi0.5Na0.5)TiO3-based ceramics.

Monomer blended electrochemical polymerization in chiral liquid crystals to produce electro-optically active copolymer

Electro-optically active low-bandgap conjugated copolymers were obtained by electrochemical polymerization (EP) in cholesteric liquid crystal (CLC). We prepared CLC electrolyte mixture blends of monomers, and electrochemically polymerized for obtaining conjugated copolymer with optical activity, in which the structure of the CLC is transferred, from achiral monomers on a CLC template. In addition, this copolymer showed a narrow bandgap and a significant red shift of the absorption band compared to the homopolymer. The optical rotatory dispersion (ORD) indicates that the polymer is chiroptically active and that the optical rotation can be tuned via redox. The guest monomers used for the EP in liquid crystal (LC) require solubility in the host LC and a rod-like structure, limiting their structural design. This technique has the advantage that complex synthesis of monomers is no required, and simple composition of monomers can be used to prepare copolymer films in a convenient manner by blending various monomers. This method expands the design range of optically active electrochromic devices based on conjugated polymers with pleochroic properties.

Spiky surface topography of heterostructured nanoparticles for programmable acceleration of multistage wound healing

Wound healing is a complex and orchestrated physiological process that involves multiple stages, including hemostasis, inflammation, proliferation, and remodeling stages. Various nanomaterials have been developed to improve the wound healing; however, most of them can only promote an individual stage of this intricate process, lacking hierarchical acceleration for multiple stages. In the present study, spiky gold-palladium heterostructured nanoparticles (AuPd SHs) were designed to possess topographical architectures on the surface of nanoparticles, capable of promoting multistage wound healing in a programmable manner. First, the spiky surface topography of AuPd SHs exhibited the potent nanobridge effect for rapid wound closure, promoting the hemostasis stage. Second, the heterostructures of AuPd SHs realized visible-light-mediated hot electron excitation and electron–hole spatial separation between Au cores and Pd spikes to efficiently generate reactive oxygen species, beneficial for the inflammation stage. Third, the spiky surface topography of AuPd SHs triggered macrophage polarization from M1 to M2 phenotype, promoting the proliferation and maturation stages. Spiky AuPd SHs with simple composition and compact structures exhibit hierarchical acceleration on multiple stages of wound healing.

Systems engineering of cybersecured digital and information measuring systems based on the signature Boolean-polynomial algebra synthesis apparatus

Development of DIMSCC models with cyber-controllability of their apparatus and software for computing function (operations) in real time becomes the primary task since the problem relevance of the cyber security of digital information and measuring systems of control complexes (DIMSCC) for critical infrastructure objects is increasing. Based on an analysis of known digital systems functional control methods new term «functional cyber-controllability of the digital informational and measuring system» was defined in the article. New approach to operational functional control of hardware redundancy is proposed. This is the synthesis of DIMSCC computing operations. Hardware redundancy is a synthesized control node chosen for functional control of various DIMSCC basic arithmetic and logical functions (operations) which should be reduced to simple procedure of corresponding switching functionally complete combinational structures from a finite set (standard set). Concerning this, the synthesis task is as follows. Only inputs and outputs of specified object are available for functional control of arithmetic and logical operations on binary operands under external hacker influence. Combination type functional control node structure (operational compositional adaptation) should be developed depending on the type of controlled computing operation being performed. The result of the synthesis task solving is a system of formulae determination (signature control equations) of the signature functional control of all DIMSCC basic arithmetic and logical functions (operations) on a single basis of a single equivalent representation of their known formulaic expression by corresponding (adequate) descriptions in infix notation (infix models). Apparatus of Boolean-polynomial algebra is used aiming to realize infix notation. The practical advantage of the proposed approach to the synthesis of hardware redundancy of operational functional signature control of computing operations is the transition possibility from signature control equations formulae to their realization implementation in the form of a signature control node directly without additional interpreting and minimizing procedures use by simple logical composition (switching) functionally complete combinational structures from a finite set (standard set).