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Two analogous tetranuclear lanthanide complexes have been synthesized with the general formula [Ln4(vht)4(MeOH)8](NO3)4·aMeOH·bH2O, where H2vht = (3,6-bis(vanillidenehydrazinyl)-1,2,4,5-tetrazine) and Ln = DyIII (1), GdIII (2). These complexes are characterized by several techniques; including single-crystal X-ray diffraction, SQUID magnetometry and single-crystal micro-SQUID hysteresis loop measurements. Elucidation of the crystal structure of the complexes shows that the lanthanide ions are bridged by a tetrazine ring, a rare bridging moiety for lanthanide ions. Magnetic studies reveal that both 1 and 2 exhibit weak ferromagnetic exchange interactions between Ln ions, and 1 displaying Single-Molecule Magnet (SMM) behaviour with a magnetisation reversal barrier of Ueff = 158 K (τ0 = 1.06 × 10−7 s). [ABSTRACT FROM AUTHOR]

We present spectroscopic measurements looking for the coherent coupling between molecular magnetic centers and microwave photons. The aim is to find the optimal conditions and the best molecular features to achieve the quantum strong coupling regime, for which coherent dynamics of hybrid photon-spin states take place. To this end, we used a high critical temperature YBCO superconducting planar resonator working at 7.7 GHz and at low temperatures to investigate three molecular mononuclear coordination compounds, namely (PPh4)2[Cu(mnt)2] (where mnt2− = maleonitriledithiolate), [ErPc2]−TBA+ (where pc2− is the phtalocyaninato and TBA+ is the tetra-n-butylammonium cation) and Dy(trensal) (where H3trensal = 2,2′,2′′-tris(salicylideneimino)triethylamine). Although the strong coupling regime was not achieved in these preliminary experiments, the results provided several hints on how to design molecular magnetic centers to be integrated into hybrid quantum circuits. [ABSTRACT FROM AUTHOR]

Rational design of small molecular gelators is an elusive and herculean task, despite the rapidly growing body of literature devoted to such gels over the past decade. The process of self-assembly, in molecular gels, is intricate and must balance parameters influencing solubility and those contrasting forces that govern epitaxial growth into axially symmetric elongated aggregates. Although the gelator–gelator interactions are of paramount importance in understanding gelation, the solvent–gelator specific (i.e., H-bonding) and nonspecific (dipole–dipole, dipole-induced and instantaneous dipole induced forces) intermolecular interactions are equally important. Solvent properties mediate the self-assembly of molecular gelators into their self-assembled fibrillar networks. Herein, solubility parameters of solvents, ranging from partition coefficients (log P), to Henry's law constants (HLC), to solvatochromic parameters (ET(30)), and Kamlet–Taft parameters (β, α and π), and to Hansen solubility parameters (δp, δd, δh), are correlated with the gelation ability of numerous classes of molecular gelators. Advanced solvent clustering techniques have led to the development of a priori tools that can identify the solvents that will be gelled and not gelled by molecular gelators. These tools will greatly aid in the development of novel gelators without solely relying on serendipitous discoveries. These tools illustrate that the quest for the universal gelator should be left in the hands of Don Quixote and as researchers we must focus on identifying gelators capable of gelling classes of solvents as there is likely no one gelator capable of gelling all solvents. [ABSTRACT FROM AUTHOR]

The thermally activated delayed fluorescence (TADF)-sensitized fluorescent (TSF) dye strategy has been used successfully in thermally evaporated organic light-emitting diodes (eOLEDs), but the development of solution-processed TSF-OLEDs (TSF-sOLEDs) is still very limited to date. Previously, the introduction of electronically inert shielding terminal groups for TADF sensitizer and/or fluorescent dyes was commonly used in TSF-sOLEDs, which aimed to achieve sufficient Förster energy transfer (FET) while restraining notorious Dexter energy transfer (DET) at a high doping concentration of fluorescent dyes. However, this approach has not yet enabled efficient TSF-sOLEDs owing to severe charge trapping emission (CTE) for triplet loss. In this study, by simply utilizing highly efficient boron-dipyrromethene derivatives (BODIPYs) that simultaneously feature high fluorescent quantum efficiency and narrow-band emission spectra, we developed highly efficient and super color-purity TSF-sOLEDs using a 0.1 wt% ultralow doping strategy. As confirmed, the resultant ultralow doping TSF-sOLEDs achieved sufficient FET from sensitizer to fluorochrome without noticeable CTE issues. The device achieves record maximum external quantum efficiency (EQE max ) and current efficiency (CE max ) of 21.5% and 78.8 cd A -1 , respectively, and an ultrapure green emission with Commission International de l'Eclairage (CIE) coordinates of (0.28, 0.65). This study validates the new device architecture of ultralow doping TSF-sOLEDs, which paves the way for future development of high-resolution TSF-sOLED displays via a simple solution-processed manufacturing approach.

Revealing the mechanism of directed transport of active matter is critical for advancing our fundamental understanding of non-equilibrium physics. Asymmetric microstructures are commonly used to rectify random movement of active particles. However, it remains unclear as to how to achieve unidirectional movement of active particles in long narrow channels. Here, we study the dynamics of active particles in a device which is divided into two chambers by V-shaped barriers and connected by a narrow channel. We find three distinct movement modes of active particles within this symmetric channel, including stochastic movement, self-sustained oscillation, and long-lived unidirectional flows. We demonstrate that the three movement modes are determined by the competition between the ratchet effect induced by the V-shaped barriers and the particle transport mediated by the long-narrow channel. Finally, we show that the unidirectional particle flow can serve as an "energy battery" to continuously supply energy for the directed transport of other objects. Our findings offer valuable insights into a unique approach for realizing unidirectional movement of active matter and open new avenues for application in microfluidics and material transport.

This work investigates the design of stimuli-responsive Pickering emulsions (PEs) for transdermal drug delivery applications, by exploring the impact of stabilising microgels size and interactions on their rheological and release properties. Temperature-responsive poly( N -isopropylacrylamide) microgels modified with 1-benzyl-3-vinylimidazolium bromide (pNIPAM- co -BVI) are synthesized in varying sizes and used to stabilise jojoba oil-in-water concentrated emulsions. The results reveals two distinct behaviours: for small microgels (∼300 nm), the PEs exhibit a smooth, uniform structure characterised by a mild yield stress, characteristic of soft glassy systems. Conversely, larger microgels (∼800 nm) induce droplet clustering, resulting in increased elasticity and a more complex yielding process. Interestingly, transdermal delivery tests demonstrate that microstructure, rather than bulk rheology, governs sustained drug release. The release process can be modelled as diffusion-controlled transport through a porous medium with random traps. At room temperature, the trap size corresponds to the droplet size, and the release time scales with the total dispersed phases volume fraction. However, at physiological temperature (37 °C), above the volume-phase transition temperature of the microgels, the release time increases significantly. The trap size approaches the microgel size, suggesting that microgel porosity becomes the dominant factor controlling drug release. Overall, the results highlight the critical role of microstructure design in optimising stimuli-responsive PEs for controlled transdermal drug delivery.

Herein, we demonstrate a practical dual ligand-enabled iron photocatalysis paradigm-converting all kinds of halogen-containing carboxylates (C n X m COO - , X: F, Cl, Br) into C n X m radicals for the valuable chloro/fluoro-polyhaloalkylation of non-activated alkenes with easily available trichloroacetonitrile/Selectfluor as the electrophilic halogenation reagent. The modular in situ assembly of the effective iron and C n X m COO - -based light-harvesting species using the two ligands-OMe/CF 3 -substituted bipyridine and acetonitrile/trichloroacetonitrile is evidenced by detailed mechanistic studies. The late-stage modification, low loading amount of iron (TON: 257) and feasible gram-scale synthesis show the utility of this protocol. We thus anticipate that the dual ligand-enabled iron photocatalysis paradigm may facilitate activation and transformation of inert bulk chemicals., Competing Interests: The authors declare that they have no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Selective S-C bond cleavage of disulfides presents a significant challenge due to the fact that S-S bonds are weaker than S-C bonds. In this study, we present a novel chloride-induced Selectfluor radical cation process for converting readily available symmetrical disulfides into unsymmetrical β-fluorodisulfides through selective S-C bond cleavage. Mechanistic investigations and DFT calculations suggest the involvement of a chlorinated disulfide radical, which subsequently reacts with alkenes to form β-fluorodisulfides via the atom transfer radical addition (ATRA) mechanism. Furthermore, this method exhibits broad functional group tolerance, enabling the synthesis of various target products in moderate to good yields.

The development of dual linkage covalent organic frameworks (DL-COFs) is fundamentally important for creating diversified structures and functions. Herein, imine-hydrazone DL-COFs were synthesized for the first time. Three novel imine-hydrazone DL-COFs have been constructed with bifunctional molecule 4-amino-2-methoxybenzohydrazide as the key building block via imine and hydrazone condensations simultaneously.

Smart windows always respond to single stimuli, which cannot satisfy various needs in practical applications. Smart windows that integrate thermotropic, electrochromic and power-generating functions in one device is highly challenging yet important in satisfying on-demand light modulation and energy efficiency in practical applications. Herein, a thermoresponsive lower critical solution temperature (LCST) ion gel was fabricated via a facile in situ polymerization of butyl acrylate in a conventional ionic liquid to explore "all in one" smart windows. The ion gel-assembled smart windows are thermotropic and electrochromic with a reliable adjustment of light transparency as well as power-generating, enabled by the ionic Soret effect of ionic liquids. Additionally, the ion gels demonstrated self-defensive robust mechanical properties, thermal insulating and antifogging properties. With such an interdisciplinary and comprehensive study of the ion gels, the LCST ion gels could fulfil the requirements of genius windows with high energy-saving potential and exceptional climate adaptability, such as shut-down of light transmission in summer, daily solar energy collection, and colour changes on demand. It conceptually updates smart windows from an energy saving to an energy supplier in buildings. It is the first time to explore the "all in one" smart windows based on integrated multifunctional ionic liquids, which could greatly bridge the gap between the materials and buildings to accelerate practical applications of smart windows.

The asymmetric synthesis of thiophene-derived compounds, including catalytic asymmetric dearomatization of thiophene and atroposelective synthesis of benzothiophene derivatives, has rarely been reported. In this work, the asymmetric transformation of the thiophene motif is investigated. Through the rational design of substrates with a thiophene structure, by using the vinylidene ortho -quinone methide (VQM) intermediate as a versatile tool, axially chiral naphthyl-benzothiophene derivatives and thiophene-dearomatized chiral spiranes were obtained in high yields with excellent enantioselectivities., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Reductive elimination is a key step in Ni-catalysed cross-couplings, which is often considered to result in new covalent bonds. Due to the weak oxidizing ability of Ni(II) species, reductive eliminations from Ni(II) centers are challenging. A thorough mechanistic understanding of this process could inspire the rational design of Ni-catalysed coupling reactions. In this article, we give an overview of recent advances in the mechanistic study of reductive elimination from Ni(II) species achieved by our group. Three possible models for reductive elimination from Ni(II) species were investigated and discussed, including direct reductive elimination, electron density-controlled reductive elimination, and oxidation-induced reductive elimination. Notably, the direct reductive elimination from Ni(II) species often requires a high activation energy in some cases. In contrast, the electron density-controlled and oxidation-induced reductive elimination pathways can significantly enhance the driving force for reductive elimination, accelerating the formation of new covalent bonds. The intricate reaction mechanisms for each of these pathways are thoroughly discussed and systematically summarized in this paper. These computational studies showcase the characteristics of three models for reductive elimination from Ni(II) species, and we hope that it will spur the development of mechanistic studies of cross-coupling reactions.

A simple aqueous complexing system of UO 2 2+ with F - is selected to systematically illustrate the application of Raman spectroscopy in exploring uranyl(VI) chemistry. Five successive complexes, UO 2 F + , UO 2 F 2 (aq), UO 2 F 3 - , UO 2 F 4 2- , and UO 2 F 5 3- , are identified, as well as the formation constants except for the 1 : 5 species UO 2 F 5 3- , which was experimentally observed here for the first time. The standard relative molar Raman scattering intensity for each species is obtained by deconvolution of the spectra collected during titrations. The results of relativistic quantum chemical first-principles and ab initio calculations are presented for the complete set of [UO 2 (H 2 O) m F n ] 2- n complexes ( n = 0-5), both for the gas phase as well as for aqueous solution modelling bulk water using the conductor-like screening model. Electronic structure calculations at the Møller-Plesset second-order perturbation theory level provide accurate geometrical parameters and in particular reveal that k water molecules in the second coordination sphere coordinating to the F - ligands in the resulting [UO 2 (H 2 O) m F n ] 2- n (H 2 O) k complexes need to be treated explicitly in order to obtain vibrational frequencies in very good agreement with experimental data. The thermodynamics and structural information obtained in this work and the developed methodology could be instructive for the future experimental and computational research on the complexation of the uranyl ion.

A tandem palladium-catalyzed Sonogashira coupling, propargyl-allenyl isomerization, and [2+2] cycloaddition sequence between electron-deficient haloarenes and 1,8-diynylic ethers is developed. The reaction shows good functional tolerance and proceeds under mild conditions to provide a new profile of benzooxepane-fused cyclobutene derivatives in moderate to high yields with high selectivity. The reaction mechanism is validated both by experimental studies and DFT calculations.

SiO-based materials as lithium-ion anodes have attracted huge attention owing to their ultrahigh capacity. However, they usually undergo severe volume expansion over the repeated lithiation/delithiation processes and have low electronic conductivity, leading to an inferior cycling stability and poor rate capability. In this study, carbon nanotubes in situ grown on the surface of commercially available micro-sized SiO ( D 50 = 5 μm) were prepared. The conductive network composed of one-dimensional carbon nanotubes could enhance its conductivity and enhance the structural stability during the cycling. The synthesized 3D-SiO@C material demonstrates good long-term cycling stability, with a reversible capacity of up to 687.7 mA h g -1 after 1000 cycles, and it maintains a high reversible capacity of 736.8 mA h g -1 , even at a high current density of 1 A g -1 .

A series of highly reduced Mo red clusters {Mo 28 } (1), {Mo 30 } (2), and {Mo 40 } (3) are synthesized from the rational assembly of planar {MoV4} building blocks and employed for proton conduction. 3 exhibits the best conductivity of 7.56 × 10 -3 S cm -1 under optimal conditions due to the most efficient hydrogen-bonding network.

Theoretical calculations are performed to elucidate the adsorption behaviors and poisoning effects of CO gas on the ZrCo surface, which drastically limits its application in hydrogen isotopic storage. Specifically, the ionic Zr-Co bond on the surface leads to unique CO adsorption structures on different sites. The CO molecule tends to prefer a tilted adsorption configuration on the Co-Co bridge site. The electronic structures, charge distributions, and bonding characteristics are further explored to study the CO adsorption properties, which obey the electron density donation and back-donation mechanism. For different CO coverages, the stepwise adsorption energies of CO increase with the increasing of coverage, reaching the saturated coverage at n CO = 11. Then, the effects of temperature and partial pressure on CO coverage are evaluated using atomic thermodynamics. The computed phase diagram shows that the ZrCo(110) surface has a stable coverage of n CO = 6 at ambient temperature under ultrahigh vacuum conditions. The pre-adsorbed CO molecules lead to the charge redistribution and the d-band center downshift on the surface, which significantly affect hydrogen adsorption and dissociation. Our results provide insights into the poisoning mechanisms of the impurity gas on ZrCo alloys, which can be beneficial for designing high-performance ZrCo-based alloys with improved poisoning tolerance.

The repair of mandibular defects is a challenging clinical problem, and associated infections often hinder the treatment, leading to failure in bone regeneration. Herein, a multifunctional platform is designed against the shortages of existing therapies for infected bone deficiency. 2D Ti 3 C 2 MXene and berberine (BBR) are effectively loaded into 3D printing biphasic calcium phosphate (BCP) scaffolds. The prepared composite scaffolds take the feature of the excellent photothermal capacity of Ti 3 C 2 as an antibacterial, mediating NIR-responsive BBR release under laser stimuli. Meanwhile, the sustained release of BBR enhances its antibacterial effect and further accelerates the bone healing process. Importantly, the integration of Ti 3 C 2 improves the mechanical properties of the 3D scaffolds, which are beneficial for new bone formation. Their remarkable biomedical performances in vitro and in vivo present the outstanding antibacterial and osteogenic properties of the Ti 3 C 2 -BBR functionalized BCP scaffolds. The synergistic therapy makes it highly promising for repairing infected bone defects and provides insights into a wide range of applications of 2D nanosheets in biomedicine.

Probiotic intervention, already showing promise in the treatment of various psychiatric disorders like depression, emerges as a potential therapy for anorexia nervosa (AN) with minimal side effects. In this study, we established an activity-based anorexia (ABA) model to probe the pathogenesis of AN and assess the impact of probiotics on ABA mice. ABA resulted in a compensatory increase in duodenal ghrelin levels, impairing the regulation of feeding and the brain reward system. Intervention with Streptococcus salivarius subsp. thermophilus CCFM1312 ameliorated these ABA-induced effects, and the activation of neurons in the nucleus tractus solitarius (NTS) was observed following probiotic administration, revealing the advantageous role of probiotics in AN through the vagus nerve. Furthermore, our metabolomics analysis of cecal contents unveiled that S. salivarius subsp. thermophilus CCFM1312 modulated gut microbiota metabolism and thereby regulated intestinal ghrelin levels.

Alcoholic liver disease is a prevalent condition resulting from excessive alcohol consumption, characterized by hepatic lipid accumulation and inflammation. This study delved into the protective effects and mechanisms of L. plantarum P101 on alcoholic liver injury in mice. As a result, L. plantarum P101 intervention reduced ALT and AST release, indicative of hepatocyte injury alleviation, while enhancing the activity of the antioxidant enzymes SOD and CAT. A reduction in pro-inflammatory cytokine TNF-α and an increase in anti-inflammatory cytokine IL-10 levels were observed in the L. plantarum P101-intervened mouse liver, signifying reduced inflammation within the mice. Furthermore, L. plantarum P101 intervention altered the gut microbial composition, primarily marked by an increase in Bacteroidota abundance, along with significant enrichment of beneficial bacteria, including Coprostanoligenes , Blautia and Lactiplantibacillus . Correlation analysis unveiled connections between serum tryptophan metabolites and the altered gut microbiota genera, suggesting that gut microbiota-driven effects may extend to extraintestinal organs through their metabolites. Intriguingly, serum indole-3-acetamide (IAM) was elevated by L. plantarum P101-regulated gut microbiota. Subsequently, the role of IAM in ameliorating alcoholic injury was explored using HepG2 cells, where it bolstered cell viability and attenuated EtOH-induced oxidative damage. Concomitantly, IAM activated the gene and protein expression of AhR in cells. Likewise, hepatic AhR expression in mice subjected to L. plantarum P101 significantly up-regulated, possibly instigated by gut microbiota-mediated IAM. Collectively, L. plantarum P101 orchestrates a modulation of gut microbiota and its metabolites, particularly IAM, to activate AhR, thereby alleviating alcoholic liver injury.

The influence of sp 2 - and sp 3 -hybridized carbon coexisting in carbon cores on fluorescence characteristics of carbon dots (CDs) was revealed by density functional theory calculations. Based on the constructed coronene-like structures, the fluorescence emission spectra, transition molecular orbital pairs and several physical quantities describing the distribution of electrons and holes were investigated. The results indicate that due to the interaction between sp 2 and sp 3 carbon atoms, two main factors including the hyperconjugative effect and the separation of sp 2 domain by sp 3 carbon atoms can regulate the fluorescence wavelength. By analyzing the transition molecular orbital pairs, it was found that the fluorescence wavelength has a close correlation with the conjugation length, suggesting that the conjugation length can predict the shift of the emission spectra of CDs. The theoretical results provide a comprehensive understanding of fluorescence mechanism and help to synthesize CDs with expected fluorescence wavelength., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

The interface microenvironment of doped quantum dots (QDs) is crucial in optimizing the properties associated with the photogenerated excitons. However, the imprecision of QDs' surface structures and compositions impedes a thorough understanding of the modulation mechanism caused by the complex interface microenvironment, particularly distinguishing the contribution of surface dopants from inner ones. Herein, we investigated interface-mediated emission using a unique model of an atomically precise chalcogenide semiconductor nanocluster containing uniform near-surface Mn 2+ dopants. Significantly, we discovered that Mn 2+ ions can directly transfer charges with hydrogen-bonding-bound electron-rich alkylamines with matched molecular configurations and electronic structures at the interface. This work provides a new pathway, the use of atomically precise nanoclusters, for analyzing and enhancing the interface-dependent properties of various doped QDs, including chalcogenides and perovskites., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Lipophilic N , N , N ', N '-tetraalkyl-diglycolamides (TRDGAs) are promising extractants for actinides separation in spent nuclear fuel reprocessing. Usually, in the extracted complexes of actinide and lanthanide ions of various oxidation states, the metal ions are completely surrounded by 2 or 3 TRDGA molecules, and the counter anions do not directly coordinate with them. In contrast, the extracted complexes of U(iv) from different media presenting different absorption spectra indicate that the anions (Cl - and NO 3 - ) are directly involved in the coordination with U(iv) in the first inner sphere. Based on this exceptional observation in solvent extraction, taking the coordination of U(iv) with N , N , N ', N '-tetramethyl-diglycolamide (TMDGA, the smallest analogue of TRDGA) as the research object, we mimic the behaviours of counterions (Cl - and NO 3 - ) and the water molecule during coordination of TMDGA with U(iv), especially combining with the simulation of the absorption spectra. We demonstrate that during the complexing of TMDGA to U(iv), the counterion Cl - will occupy one coordination number in the inner coordination sphere, and NO 3 - will occupy two by bidentate type; however, the ubiquitous water cannot squeeze in the inner coordination sphere. In addition, the coordination of Cl - and NO 3 - is proved to favour the extraction with the lower binding energy. Moreover, the simulation of absorption spectra is in good agreement with the observation from experiments, further verifying the aforementioned conclusion. This work in some way will provide guidance to improve the computation methods in research of actinides by mimicking the absorption spectra of actinide ions in different complexes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Fabrication of an organic polymer nanofiltration membrane with both high water permeability and high salt rejection is still a big challenge. Herein, phytic acid (PhA)-modified graphene oxide (GO) was used as the membrane thickness modifier, which was introduced into the thin-film nanoparticle composite (TFN) membrane via in situ interfacial polymerization (IP) on a porous substrate. The water flux of the optimally tuned TFN-GP-0.2 composite membrane is 48.9 L m -2 h -1 , which is 1.3 times that of the pristine thin-film composite (TFC) nanofiltration membrane (37.9 L m -2 h -1 ) (GP represents the PhA modified GO composite). The rejection rate of 2000 ppm MgSO 4 for TFN-GP-0.2 membranes was maintained at 97.5%. The increased water flux of the TFN-GP composite membrane compared to that of the TFN nanofiltration membrane was mainly attributed to enhanced hydrophilicity and reduced thickness of the polyamide (PA) layer. Molecular dynamics (MD) simulations confirm that the diffusion rate of amine monomers is reduced by the presence of a GP complex in the IP process, which facilitates the formation of PA layer with thinner thickness. In addition, the TFN-GP-0.2 composite membrane also showed good long-term stability; after 12 h of continuous operation, the water flux only decreased by 0.1%. This study sheds new light on the development of GO-based nanofiltration for potential implementation, as well as a unique concept for manufacturing high-performance nanofiltration membranes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Inorganic lead halide perovskite quantum dots (CsPbX 3 QDs (X = Cl, Br, or I)) have attracted more and more attention due to their high absorption coefficient, narrow emission band, high quantum efficiency, and tunable emission wavelength. However, CsPbX 3 QDs are decomposed when exposed to bright light, heat, moisture, etc ., which leads to severe luminous attenuation and limits their commercial application. In this paper, CsPbBr 3 @glass materials were successfully synthesized by a one-step self-crystallization method, including melting, quenching and heat treatment processes. The stability of CsPbBr 3 QDs was improved by embedding CsPbBr 3 QDs into zinc-borosilicate glass. Then, the CsPbBr 3 @glass was combined with polyurethane (PU) to form a flexible composite luminescent film CsPbBr 3 @glass@PU. This strategy enables the transformation of rigid perovskite quantum dot glass into flexible luminescent film materials and further improves the photoluminescence quantum yield (PLQY) from 50.5% to 70.2%. The flexible film has good tensile properties, and its length can be strained 5 times as long as the original length. Finally, a white LED was encapsulated by combining CsPbBr 3 @glass@PU film and red phosphor K 2 SiF 6 :Mn 4+ with a blue LED chip. The good performance of the obtained CsPbBr 3 @glass@PU film indicates that it has potential application in flexible liquid crystal displays (LCDs) as a backlight source.

Microfluidic impedance cytometry is emerging as a label-free, low-cost and portable solution for cell analysis. Impedance-based cell or particle characterization is provided by microfluidic and electronic devices. We report the design and characterization of a miniaturized flow cytometer based on a 3-dimensional (3D) hydrodynamic focusing mechanism. A sheath adaptively concentrated the sample laterally and vertically at the bottom of the microchannel, reducing the variance of particle translocation height and increasing the signal-to-noise ratio of the particle impedance pulse. Through simulation and confocal microscopy experiments, it has been verified that an increase in the ratio of sheath to sample decreased the cross-sectional area of the concentrated stream, which can be reduced to 26.50% of the pre-focusing value. The appropriate sheath flow settings increased the impedance pulse amplitude for different particles, and the coefficient of variation reduced by at least 35.85%, contributing to a more accurate representation of the particle impedance characteristic distribution. The system displayed the difference of HepG2 cell impedance before and after drug treatment, which is consistent with the results of flow cytometry, providing a convenient and inexpensive solution for monitoring cell status.

Transition metal and nitrogen co-doped carbon materials (M-N-C) have attracted great attention in the field of catalysis due to their high atomic utilization and outstanding catalytic performance. Herein, a series of Co and N-doped carbon catalysts (Co-N-C@mSiO 2 - x ) were successfully prepared by pyrolysis of cobalt porphyrins in situ synthesized in the cavity of mesoporous hollow silica spheres according to a ship-in-bottle method. The optimal catalyst exhibited excellent catalytic performance for the selective oxidation of ethylbenzene, with 95.5% conversion for ethylbenzene and 98.9% selectivity toward acetophenone. In combination with characterization techniques, acid treatment experiments and KSCN poisoning tests, the successful synthesis of cobalt-porphyrins in hollow silica spheres was demonstrated, and the excellent performance of Co-N-C@mSiO 2 -0.10 was attributed to the more acid-resistant Co-N x species as the main metal active center. In addition, the N-containing groups could significantly facilitate the conversion of ethylbenzene. This work is expected to provide a straightforward and green approach to design metal and N co-doped carbon materials.

Bovine casein hydrolysates (CHs) have demonstrated sleep-promoting activities. However, only few peptides were identified from CHs with sleep-promoting effects. In this work, an in vitro model based on the electrophysiology of brain neurons was established for the evaluation of sleep-promoting effects. Based on this model, four novel peptides were systematically separated from CH. Compared with the control group, the action potential (AP) inhibitory rate of four peptides increased by 38.63%, 340.93%, 233.28%, and 900%, respectively, and the membrane potential (MP) change rate of four peptides increased by 319.78%, 503.09%, 381.22%, and 547.10%, respectively. These results suggested that four peptides have sleep-promoting activities. Furthermore, Caenorhabditis elegans ( C. elegans ) sleep behavior results indicated that all the four peptides could significantly increase the total sleep duration, the motionless sleep duration of C. elegans , implying that these four peptides can significantly improve sleep. The LC-MS/MS results showed that the primary structures of these novel peptides were HQGLPQEVLNENLLR (α s1 -CN, f8-22), YKVPQLEIVPNSAEER (α s1 -CN, f104-119), HPIKHQGLPQEVLNENLLR (α s1 -CN, f4-22), and VPQLEIVPNSAEER (α s1 -CN, f106-119). Overall, this study revealed that the four novel sleep-promoting peptides identified were strong candidates as potential functional ingredients in the development of sleep-promoting products.

Active particles without detailed balance can rectify their random motions to drive the directed movement or rotation of asymmetric passive obstacles. However, whether they can drive the directed movement of symmetric passive obstacles is still unclear. Here, we show that a rod-like passive particle which is fixed to move along the x -axis in an active bath can keep long-lived directed movement at nearly constant speed due to the spontaneous symmetry breaking of the neighboring active particle cluster. If the passive particle is further confined by a harmonic potential, it may undergo self-sustained periodic oscillation for an appropriate length of the passive particle and self-propelled velocity of active particles. The restoring force from the harmonic potential will trigger the velocity jump-off and thus lead to self-sustained periodic oscillation. Remarkably, the relationship between the velocity of the passive particle and the external force shows that the effective viscosity of the active bath may become negative in some regime. Finally, we develop a minimum 1D theoretical model to further probe the mechanism underlying the directed movement and self-sustained oscillation of the passive particle. Our findings reveal the effect of the moving boundary on the active bath and demonstrate a novel method to extract practical mechanical work from the active bath to propel microdevices.

The conversion of the common ginsenoside Rb1 to the rare ginsenoside compound K (CK) using snailase (Sna) is an efficient method for industrial production. In order to improve the stability and recoverability of Sna during the catalytic conversion of ginsenosides, the cage-like immobilised Sna material ZIF-ZnCo-Sna and the hybrid nanoflower-based immobilised Sna material Asp@ZIF-ZnCo-Sna modified with L-aspartic acid (Asp) were synthesised using a one-step method. The addition of Asp provides a richer ligand pattern and the morphology of the material changed from a cage to a hybrid nanoflower. The modified hybrid nanoflower Asp@ZIF-ZnCo-Sna has a larger specific surface area, resulting in an enzyme loading of 142.57 mg g -1 . The more abundant mesopores allowed the enzyme to maintain a good conformation and the enzyme activity was 79.8% of that of the free Sna. In addition, the total conversion rate of Asp@ZIF-ZnCo-Sna to ginsenoside Rb1 was as high as 88.35%, whereas that of ZIF-ZnCo-Sna was 79.12%. Moreover, after 6 cycles, the catalytic conversion of ZIF-ZnCo-Sna and Asp@ZIF-ZnCo-Sna and the crystalline shape remained the same, indicating that both composites have good stability and catalytic properties. This new approach of improving the MOF morphology and enzymatic activity by a one-step addition of small biological molecules provides a simple, rapid, and effective strategy for biocatalysis. It also provides a certain reference value for the immobilized Sna to produce rare ginsenoside CK.

Boronic acids have become one of the most prevalent classes of reagents in modern organic synthesis, displaying various reactivity profiles via C-B bond cleavage. Herein, we describe the utilization of a readily available boronic acid as an efficient surrogate of hydroxide upon activation via fluoride complexation. The hitherto unknown aryne induced ring-opening reaction of cyclic sulfides and three-component coupling of fluoro-azaarenes are developed to exemplify the application value. Different from metal hydroxides or water, this novel hydroxy source displays mild activation conditions, great functionality tolerance and structural tunability, which shall engender a new synthetic paradigm and in a broad context offer new blueprints for organoboron chemistry. Detailed computational studies also recognize the fluoride activation mode, provide in-depth insights into the unprecedented mechanistic pathway and elucidate the reactivity difference of ArB(OH) x F y complexes, which fully support the experimental data., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Glucose metabolism disorder triggered by a high-energy diet is associated with circadian disruption in the brain, peripheral tissues and gut microbiota. The present study aims to investigate the regulating effects of capsaicin (CAP) on the diet-induced disturbances of glucose homeostasis and gut microbiota in respect of circadian rhythm-related mechanisms. Our results indicated that CAP significantly ameliorated glucose metabolism disorder in mice induced by a high-fat and high-fructose diet (HFFD). The rhythmic expressions of circadian clock genes ( Bmal1 , Clock , and others) and glucose metabolism-related genes ( Pgc-1α , Glut2 , G6pc , and Pepck ) in the liver disrupted by an abnormal diet were also recovered by CAP. Microbial studies using 16S rDNA sequencing revealed that CAP modulated the structure and composition of gut microbiota and improved the circadian oscillations of Firmicutes and Bacteroidetes at the phylum level and Allobaculum , Bacteroides , Bifidobacterium , and Alistipes at the genus level. Correlation analysis indicated that a close correlation existed between intestinal microbiota, hepatic circadian gene expressions and the level of glucose metabolism-related factors, indicating that CAP could alleviate HFFD-induced disturbances of glucose metabolism and gut microbiota associated with circadian clock related mechanisms.

The assembly of inflammasomes drives caspase-1 activation, which further promotes proinflammatory cytokine secretion and downstream pyroptosis. The discovery of novel caspase-1 inhibitors is pivotal to developing new therapeutic means for inflammasome-involved diseases. In our present study, sennoside A (Sen A), a popular ingredient in multiple weight-loss medicines and dietary supplements, is found to potently inhibit the enzymatic activity of caspase-1 in vitro . Sen A considerably decreased IL-1β production in macrophages stimulated by LPS plus ATP, nigericin or MSU as well as poly(dA:dT) transfection, and remedied ROS-involved pyroptosis via caspase-1 inhibition. Mechanistically, Sen A not only suppressed the assembly of both NLRP3 and AIM2 inflammasome but also affected the priming process of NLRP3 inflammasome by blocking NF-κB signaling. Sen A significantly ameliorated the pathophysiological effect in LPS-, MSU- and carrageenan-challenged rodent models by suppressing inflammasome activation. Furthermore, P2X7 was indispensable for Sen A inhibiting NLRP3 inflammasome since it failed to further decrease IL-1β and IL-18 production in LPS plus ATP-stimulated BMDMs that were transfected with P2X7 siRNA. Sen A also restrained the large pore-forming functionalities of the P2X7R as verified by the YO-PRO-1 uptake assay. Taken together, Sen A inactivates caspase-1 to inhibit NLRP3 and AIM2 inflammasome-involved inflammation in a P2X7-dependent manner, making it an attractive candidate as a caspase-1 small-molecular inhibitor.

We report the first example of a perovskite sulfate [Na 3 (H 2 O)]Fe(SO 4 ) 3 . Further structure modulation, by dimensional reduction or ligand extension, has resulted in two related layered perovskite-like compounds Na 6 Fe(SO 4 ) 4 and Na 12 Fe 3 (SO 4 ) 6 F 8 . Taken together, these results open up a more general strategy for the future design of more complex perovskite-related materials.

Bridged tetracyclic nitrogen scaffolds are found in numerous biologically active molecules and medicinally relevant structures. Traditional methods usually require tedious reaction steps, and/or the use of structurally specific starting materials. We report an unprecedented, iminyl radical-triggered relay annulation from oxime-derived peresters and azadienes, which shows good substrate scope and functional group compatibility, and can deliver various bridged aza-tetracyclic compounds with complex molecular topology and four contiguous stereogenic centers (dr > 19 : 1) in a single operation. This transformation represents the first example of trifunctionalization of iminyl radicals through simultaneous formation of one C-N and two C-C bonds. DFT calculation studies were conducted to obtain an in-depth insight into the reaction pathways, which revealed that the reactions involved an interesting 1,6-hydrogen atom transfer process., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

To achieve the most efficient, all-exciton-harvesting organic electrochemiluminescence (ECL) for biosensing, aqueous thermally activated delayed fluorescence (TADF)-ECL (aqueous TADF-ECL) was successfully launched to provide a breakthrough for the theoretical ECL efficiency limitation of aqueous fluorescence ECL (aqueous FL-ECL). However, achieving efficient TADF emitters suitable for aqueous TADF-ECL remains challenging. A previous strategy relied on TADF small molecular nanoparticles (NPs). However, the aggregation caused quenching of such TADF molecules within NPs is intense, which renders such NPs inefficient for ECL emission. Herein, we propose developing conjugated polymer dots (Pdots) based aqueous TADF-ECL. Compared to the intrinsic TADF polymer, the Pdots achieve a comparable TADF photophysical properties in water, i.e. , the comparable PL spectra, similar PL quantum efficiency ( Φ PL ) and intense delayed fluorescent contributions via a fast reverse intersystem crossing rate ( k RISC ) of 1.5 × 10 6 s -1 . The resultant relative ECL efficiency ( Φ ECL ) of the oxidative-reduction ECL system (C 2 O 4 2- as the co-reactant) is as high as 11.73% ( vs. the Ru(bpy) 3 2+ counterpart). Additionally, satisfactory dopamine biosensing was accomplished for such TADF-Pdots/C 2 O 4 2- couple. All those results are combined to highlight the promising potential of such an aqueous TADF-ECL strategy.

A visible-light-induced, transition-metal and photosensitizer-free cross-coupling of aryl iodides with hydrazones was developed. In this strategy, hydrazones were used as alternatives to organometallic reagents, in the absence of a transition metal or an external photosensitizer, making this cross-coupling mild and green. The protocol was compatible with a variety of functionalities, including methyl, methoxy, trifluoromethyl, halogen, and heteroaromatic rings. Mechanistic investigations showed that the association of the hydrazone anion with aryl halides formed an electron donor-acceptor complex, which when excited with visible light generated an aryl radical via single-electron transfer., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Herein, we report a Pd-catalyzed regiospecific cycloaromatization of β -bromoenal and vinyl borate esters to synthesize m -alkenyl substituted benzaldehydes. This allows the construction of complex molecules from simple materials, which may be useful in the search for new optical materials.

A new class of stable four-coordinated benzotriazole-borane compounds was developed via gold-catalyzed alkyne hydroboration. The application of polymeric (BH 2 CN) n reagent gave the formation of cyano-amine-boranes (CAB) complexes with less basic N-heterocyclic amines and anilines. Various new CABs were investigated in catalytic hydroboration to synthesize N-B cycles. The 1,2,3-benzotriazoles were identified as the only feasible N-source, giving the four coordinated borane N-B cycles (BTAB) in excellent yields (up to 90%) with good functional group tolerability. This new class of polycyclic N-B compounds showed excellent stability toward acid, base, high temperature, and photo-irradiation. The facile synthesis, excellent stability, strong and tunable fluorescence emission make BTAB interesting new fluorescent probes for future chemical and biological applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Secoisolariciresinol diglucoside (SDG) has a strong anti-inflammatory effect, which depends partly on the participation of gut microbiota. We studied the effect of SDG on colonic inflammation caused by a common poor diet, high-fat diet (HFD), and the regulation of gut microbiota as well as its metabolites. Considering the difference of sources, prices, and possible bioactivity, we compared the effects of a single compound and the extract of SDG on colon inflammation. The results displayed that both the single compound and the extract ameliorated morphologic damage of the colon and improved intestinal barrier integrity. In addition, SDG suppressed the mRNA expressions of inflammatory cytokines in the colon, and the inhibitory effect of a single compound was stronger than that of the extract. The results of 16S rRNA sequencing showed that SDG altered the diversity and composition of gut microbiota, particularly the abundance of inflammation-related bacteria, and the effect of the extract was greater than that of a single compound. The analysis of short-chain fatty acids (SCFAs) manifested the improved concentration with the intervention of SDG. These results confirmed that SDG, including a single compound and extract, exerted protective effects against colon inflammation, which might be partly explained by the gut microbiome. Our research could provide a positive nutritional intervention for chronic intestinal inflammation.

Obesity has been reported to be associated with gut microbiome dysbiosis. seabuckthorn fruits have traditionally been used in Tibetan foods and medicines for thousands of years. Seabuckthorn polysaccharide (SP) is one of the main functional components in seabuckthorn fruits. However, the effects of SP on a high-fat diet (HFD)-induced obesity have not yet been elucidated. The purpose of this study is to explore the amelioration effect of SP on obesity induced by HFD and to reveal its mechanism of gut microbiota and its metabolites. Results showed that 12-week SP (0.1%, w/w) dietary supplementation could significantly reduce body weight gain, serum lipid level and liver triglycerides level in obese mice. Notably, the SP treatment elevated p-AMPKα and PPARα proteins expression stimulated the phosphorylation of ACC1 and inhibited the protein expression of FAS, PPARγ, and CD36 in the mice liver. Further, SP also reorganized the gut microbiome by up-regulating the proportion of Muribaculaceae_unclassified , Bifidobacterium , Rikenellaceae_RC9_gut_group , Alistipes , and Bacteroides , and down-regulating the abundance of Lactobacillus , Firmicutes_unclassified, Dubosiella Bilophila , and Streptococcus in HFD-induced obese mice. Moreover, the production of microbial metabolites short-chain fatty acids (SCFAs) in feces has also increased. In addition, correlation analysis results showed that obesity-ameliorating effects of SP were highly associated with levels of SCFAs in feces. Therefore, the regulation of SP on liver lipid metabolism may be due to the variation of the gut microbiome and raised production of SCFAs. These results indicate that SP could play the part of a potential nutraceutical for ameliorating obesity through regulation of the gut-liver axis.

The complexation of solid uranyl nitrate with tri- n -butyl phosphate (TBP) in supercritical CO 2 is quite different from that of a liquid-liquid extraction system because fewer water molecules are involved. Here, the complexation mechanism was investigated by molecular dynamics simulation, emphasising on speciation distribution analysis. In the anhydrous uranyl nitrate system, poly-core uranyl-TBP species [UO 2 (NO 3 ) 2 ] 2 ·3TBP and [UO 2 (NO 3 ) 2 ] 3 ·3TBP were formed in addition to the predominant [UO 2 (NO 3 ) 2 ]·1TBP and [UO 2 (NO 3 ) 2 ]·2TBP species. The poly-core species was mainly constructed via the linkage of U[double bond, length as m-dash]O⋯U contributed by pre-developed [UO 2 (NO 3 ) 2 ]·1TBP species. However, in the hydrated uranyl nitrate system, TBP·[UO 2 (NO 3 ) 2 ]·H 2 O species form, preventing the formation of the poly-core species. The complexation developed differently depending on the TBP to the uranyl nitrate ratio, the solute densities and the participation of water. It suggested that the kinetically favoring species would gradually convert into the thermodynamically stable species [UO 2 (NO 3 ) 2 ]·2TBP by ligand exchange., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)