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Applications of luminescent quantum dots require the materials to be stable under a wide range of temperatures, photon fluxes and chemical environments. In this work, we demonstrate that Al2O3 shells synthesized by atomic layer deposition on films of CdTe quantum dots are effective to prevent chemical degradation for up to 17 hours under continuous illumination at 90 °C in ambient air. Control samples with no Al2O3 coating experienced extensive oxidation and severe quenching of the photoluminescence intensity under these conditions. [ABSTRACT FROM AUTHOR]

The geometrical control of atom transfer radical addition (ATRA) reactions to alkynes poses significant challenges. Herein, we present a uniform solution by developing a stereodivergent synthetic method for both isomers of the resulting alkene products, starting from the same materials. The synthesis of the thermodynamically more stable isomer utilizes the strategy of uphill catalysis while the accumulation of the less stable isomer is facilitated by a manganese-catalyzed iodo-abstraction/radical rebound process, taking advantage of its reversibility. Various substituted alkyl iodides can be used to provide easy access to both isomers of iodoalkene products with valuable functional groups such as CF 3 , CF 2 H, CN, ester, or amide at the allylic position.

Light-emitting electrochemical cells (LECs) are appealing for cost-effective, large-area emission applications; however, their luminescence efficiency is significantly limited by exciton annihilation caused by high concentration polarons. Here, we present thermally activated delayed fluorescence (TADF) sensitized fluorescence LECs (TSF-LECs) that achieve a record 9% EQE. The TADF sensitizers with rapid reverse intersystem crossing (RISC) rates can effectively convert triplet excitons to singlet excitons in LECs, thereby establishing a more efficient overall energy transfer pathway. Importantly, magneto-electroluminescence measurements indicate that the additional RISC route in TSF-LECs significantly suppresses the annihilation of triplet excitons and thus reduces exciton loss under high concentration polaron conditions. Compared to LECs without a sensitizer, TSF-LECs exhibit improved EQE and luminance, extended operational lifetimes, and suppressed efficiency roll-off. A flexible display prototype based on TSF-LECs was further fabricated, capable of stably displaying high-brightness preset patterns for extended periods. The exploration of the exciton dynamics in high concentration polaron environments offers valuable insights for future developments in high-efficiency LEC technology.

Mesenchymal stem cells (MSCs) exhibit substantial potential for osteoarthritis (OA) therapy through cartilage regeneration, yet the realization of optimal therapeutic outcomes is hampered by their limited intrinsic reparative capacities. Herein, MSCs are engineered with circular mRNA (cmRNA) encoding fibroblast growth factor 18 (FGF18) encapsulated within lipid nanoparticles (LNP) derived from a glycerolipid to facilitate OA healing. A proprietary biodegradable and ionizable glycerolipid, TG6A, with branched tails and five ester bonds, forms LNP exhibiting above 9-fold and 41-fold higher EGFP protein expression in MSCs than commercial LNP from DLin-MC3-DMA and ALC-0315, respectively. The introduction of FGF18 not only augmented the proliferative capacity of MSCs but also upregulated the expression of chondrogenic genes and glycosaminoglycan (GAG) content. Additionally, FGF18 enhanced the production of proteoglycans and type II collagen in chondrocyte pellet cultures in a three-dimensional culture. In an OA rat model, transplantation with FGF18-engineered MSCs remarkably preserved cartilage integrity and facilitated functional repair of cartilage lesions, as evidenced by thicker cartilage layers, reduced histopathological scores, maintenance of zone structure, and incremental type II collagen and extracellular matrix (ECM) deposition. Taken together, our findings suggest that TG6A-based LNP loading with cmRNA for engineering MSCs present an innovative strategy to overcome the current limitations in OA treatment.

V 3 O 7 ·H 2 O (VO) stands out as a highly promising cathode material for aqueous zinc-ion batteries (AZIB). However, due to the instability of the VO structure and the limited ion transport rate, achieving the required specific capacity and extended cycling lifespan has been challenging. To tackle this issue, we synthesized Mg-ion intercalated VO (MgVO) using a straightforward hydrothermal method. Introducing Mg 2+ as an interlayer support enhanced the flexibility of MgVO within the confined layer space, stabilized its lamellar structure, and expanded the VO layer spacing. The AZIB employing the MgVO cathode demonstrated a high specific capacity of 382.7 mA h g -1 at a current density of 0.1 A g -1 and showed excellent cycling stability. The robust structural stability of MgVO suggests promising applications for large-scale energy storage, while the Mg 2+ intercalation strategy presents a novel approach for exploring other potential cathode materials.

Acid-catalyzed Friedel-Crafts-type cyclization of tetrapyrrolic BF 2 complex 1 and α,α'-dibromotripyrrin 2 gave 5,10,23-trimesityl [28]heptaphyrin(1.1.0.0.1.0.0) BF 2 complex 3BF 2 as a stable and moderate antiaromatic macrocycle. Demetalation of 3BF 2 with methanesulfonic acid followed by treatment with HCl gave free-base salt 3HCl that holds a chloride anion at the core. This salt displays a planar structure with an inverted pyrrole and a stronger paratropic ring current. Metalation of neutral free-base 3 with PdCl 2 gave bis-Pd II complex 3Pd 2 as a stable antiaromatic molecule. The 1 H NMR spectrum of 3Pd 2 displays signals due to pyrrolic β-protons in the range of -1.06 ∼ -1.90 ppm, indicating the unprecedented strong paratropic ring current., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Ni II porphyrin (P) and Ni II 5,15-diazaporphyrin (DAP) hybrid tapes were synthesized by Suzuki-Miyaura cross-coupling reactions of meso - or β-borylated P with β-brominated DAP followed by intramolecular oxidative fusion reactions. Meso -β doubly linked hybrid tapes were synthesized by oxidation of singly linked precursors with DDQ-FeCl 3 . Synthesis of triply linked hybrid tapes was achieved by oxidation with DDQ-FeCl 3 -AgOTf with suppression of peripheral β-chlorination. In these tapes, DAP segments were present as a 20π-electronic unit, but their local antiaromatic contribution was trivial. Remarkably, these hybrid tapes were stable and exhibited extremely enhanced absorption bands in the NIR region and multiple reversible redox waves. A pentameric hybrid tape showed a remarkably sharp and red-shifted band at 1168 nm with ε = 5.75 × 10 5 M -1 cm -1 . Singly linked P-DAP dyads were oxidized with DDQ-FeCl 3 to give stable radicals, which were oxidized further to afford dimeric hybrid tapes possessing a nitrogen atom at the peripheral-side meso -position., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Direct CO 2 hydrogenation to value-added chemicals is a promising path toward realizing the "carbon-neutral" goal. However, controlling the selectivity of CO 2 hydrogenation toward desired products ( e.g. , CO and CH 4 ) using non-precious metal-based catalysts is important but challenging. It is imperative to explore catalysts with high activity and stability. Herein, boron-doped cobalt nanoparticles supported on H-ZSM-5 were devised for CO 2 hydrogenation to produce CO in a gas-solid flow system. Our results demonstrate that boron doping not only increases the CO 2 adsorption capability of the catalyst but also optimizes the electronic state of Co for CO desorption during hydrogenation process. As a result, the boron-doped cobalt catalysts displayed an enhanced CO selectivity of 94.5% and a CO 2 conversion rate of 45.6%, which is much higher than that of Co-ZSM-5 without boron doping. This study shows that the strategic design of metal borides is important for controlling the selectivity of desired products in the CO 2 hydrogenation reaction., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The hydration process of cement-based materials primarily results in the formation of calcium silicate hydrate (CSH), which is crucial in deciding how long concrete will last. This study utilizes molecular dynamics simulation technology to explore the freezing behavior of pure water solutions within various calcium silicate hydrate (CSH) matrices. The investigated matrices encompass four different Ca/Si ratios. According to the simulation, as ice crystals develop close to the surface of CSH, the CSH matrix strengthens its hydrogen and ionic interactions with water molecules, which effectively prevents water molecules from crystallizing and nucleating. Consequently, these molecules compose an unfrozen water film structure that bridges between ice crystals and the CSH matrix. The research also reveals an intriguing relationship between silica chain behavior on the Ca/Si ratio and the CSH surface. Surface flaws arise as a result of the silica chains of CSH breaking into shorter segments as the Ca/Si ratio increases. These surface defects manifest as grooves on the matrix's surface, effectively capturing and retaining specific water molecules. The CSH matrix's hydrogen bonds with water molecules are weakened as a result of this process, facilitating their participation in the crystallization process, and leading to a thinner unfrozen water film thickness with an increased Ca/Si ratio. This study contributes to a greater knowledge of the performance and dependability of cement-based products by offering molecular-level insights into the freezing actions of liquids in gel pores.

Objectives : Fine particulate matter (PM 2.5 ), a small molecule particulate pollutant, can reach the lungs via respiration and cause lung damage. Currently, effective strategies and measures are lacking to prevent and treat the pulmonary toxicity of PM 2.5 . Astaxanthin (ASX), a natural xanthophyll carotenoid, has attracted attention due to its unique biological activity. Our research aims to probe into the prevention and treatment of ASX on PM 2.5 -induced lung injury and clarify its potential mechanism. Methods : Sprague-Dawley (SD) rats were given olive oil and different concentrations of ASX orally daily for 21 days. PM 2.5 suspension was instilled into the trachea of rats every two days for one week to successfully develop the PM 2.5 exposure model in the PM 2.5 -exposed and ASX-treated groups of rats. The bronchoalveolar lavage fluid (BALF) was collected, and the content of lung injury-related markers was detected. Histomorphological changes and expression of markers associated with oxidative stress, inflammation, iron death, and apoptosis were detected in lung tissue. Results : PM 2.5 exposure can cause changes in lung histochemistry and increase the expression levels of TP, AKP, ALB, and LDH in the BALF. Simultaneously, inflammatory responses and oxidative stress were promoted in rat lung tissue after exposure to particulate matter. Additionally, ASX preconditioning can alleviate histomorphological changes, oxidative stress, and inflammation caused by PM 2.5 and reduce PM 2.5 -related ferroptosis and apoptosis. Conclusion : ASX preconditioning can alleviate lung injury after PM 2.5 exposure by inhibiting ferroptosis and apoptosis.

Nanopore sensing is at the forefront of the technological revolution of the protein research field and has been widely used in molecular diagnosis and molecular dynamics, as well as for various sequencing applications. However, direct protein sensing with biological nanopores is still challenging owing to the large molecular size. Here, we propose an aptamer-assisted nanopore strategy for direct protein sensing and demonstrate its proof-of-concept utilities by experiments with SARS-Cov-2 nucleocapsid protein (NP), the most abundantly expressed viral protein, that is widely used in clinical diagnosis for COVID-19. NP binds with an oligonucleotide-tailed aptamer to form a protein-DNA complex which induces a discriminative two-level pattern of current blockades. We reveal the potential molecular interaction mechanism for the characteristic blockades and identify the salt gradient condition as the dominant factor of the phenomenon. Furthermore, we achieve a high sensitivity of 10 pM for NP detection within one hour and make a preliminary exploration on clinical diagnosis. This work promises a new platform for rapid and label-free protein detection.

Inorganic nanoparticles with long-chain ligands are usually hydrophobic. However, simple and practical methods for converting hydrophobic nanoparticles to hydrophilic nanoparticles are still lacking. Herein, we developed a general method involving using dimercaptosuccinic acid (DMSA) for endowing hydrophobic nanoparticles with water dispersion abilities. By mixing a tetrahydrofuran solution of DMSA with a cyclohexane solution of hydrophobic nanoparticles, the long-chain ligands were replaced with DMSA, with the replacement due to the strong and broad-spectrum coordination abilities of sulphydryls and carboxyls. Four representative kinds of hydrophobic nanoparticles, namely Ag, NaGdF 4 , TiO 2 , and ZnS nanoparticles, were selected for verifying the performance of this DMSA-based modification method. Meanwhile, this method can also widen the applications of hydrophobic nanoparticles and facilitate their being subjected to further graft modifications. We hope that our research will increase the chances for applications of nanomaterials to be made.

The zeolitic imidazole framework with a leaf-shaped morphology (ZIF-L) has a wide range of promising applications in gas storage, battery materials, catalytic reactions, and optoelectronic devices due to its planar leaf-like structure and large surface area. However, the low conductivity, weak catalytic activity, and poor stability in the water dielectric medium of ZIF-L limit its further practical application. To solve these problems, we added the conductive polymer heterocyclic poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to ZIF-L for the sensitive detection of dopamine (DA). The synthesized composite ZIF-L/PEDOT:PSS (ZIF-L/PEDOT) not only retained the surface morphology of ZIF-L but also exhibited excellent electrochemical properties. The higher electrical conductivity of ZIF-L/PEDOT than that of ZIF-L was due to the enhanced electron transfer at the interface between ZIF-L and PEDOT:PSS. As a result, we developed an electrochemical biosensor based on the ZIF-L/PEDOT composite, which has a limit of detection of 7 nM for DA and a wide linear range from 25 nM to 500 μM. Furthermore, the current drop was negligible after 28 days, proving that the biosensor has excellent stability. Based on the above-mentioned outstanding performance, the ZIF-L/PEDOT-based biosensor was successfully used to detect DA in human serum samples. These results demonstrated that ZIF-L/PEDOT is expected to play an essential role in disease detection.

A systematic quantum-chemical study of the hydrogenation of ethene, catalyzed by strong acids HX (X = F, Cl, Br) and superacids HA (A = MgX 3 , Mg 2 X 5 ; X = F, Cl, Br) arising from octet superhalogens is explored. Two possible paths are proposed, concerted and stepwise, and the calculated results show that the concerted path is more favorable than the stepwise path. Compared to the hydrogenation reaction without any catalyst, the improvement of the catalytic efficiency of the superacid HA (A = MgX 3 , Mg 2 X 5 ) is high, up to 38.8 to 59.4%. Compared to the strong acid HX (X = F, Cl, Br), the barrier energy is significantly reduced and the improvement of the catalytic efficiency of the superacid HA reaches 23.1 to 31.7%. In particular, for HMg 2 Br 5 , the barrier energy of the hydrogenation of ethene is only 36 kcal mol -1 , which shows that the reaction could proceed under experimental conditions. In addition, the results show that the catalytic efficiency of the superacid HA is related to the acidity of the superacid. In general, the greater the acidity, the lower the barrier energy and the easier the hydrogenation reaction. From the analysis of the bond order, the newly formed C-H bond of the transition state (TS3) in the concerted path, in which the H atom comes from the superacid catalyst, directly affects the barrier energy of the entire reaction. For the more acidic catalyst, this H atom is provided more easily, and then the formed C-H bond in the transition state is stronger. Consequently, this stronger bond leads to a more stable transition state, and hence to a lower energy barrier as well as a higher efficiency of the superacid catalyst. Therefore, a positive correlation between the acidity of the metal-free catalyst and its catalytic efficiency is expected in the hydrogenation reaction.

An electron acceptor based on a quinoidal dipyrrolopyrazinedione core was synthesized for organic solar cells and photodetectors. A power conversion efficiency of 6.7% and a specific detectivity of 4.1 × 10 13 Jones at 800 nm have been obtained, suggesting the promising prospects of quinoidal molecules for optoelectronic devices.

Hierarchical self-assembly of organic molecules or assemblies is of great importance for organic photonics to move from fundamental research to integrated and practical applications. Magnetic fields with the advantages of high controllability, non-contact manipulation, and instantaneous response have emerged as an elegant way to prepare organic hierarchical nanostructures. In this perspective, we outline the development history of organic photonic materials and highlight the importance of organic hierarchical nanostructures for a wide range of applications, including microlasers, optical displays, information encoding, sensing, and beyond. Then, we will discuss recent advances in magnetically controlled assembly for creating organic hierarchical nanostructures, with a particular focus on their potential for enabling the development of integrated photonic devices with unprecedented functionality and performance. Finally, we present several perspectives on the further development of magnetically controlled assembly strategies from the perspective of performance optimization and functional design of organic integrated photonics., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Single-molecule magnets (SMMs) have great potential in becoming revolutionary materials for micro-electronic devices. As one type of SMM and holding the performance record, lanthanide single-ion magnets (Ln-SIMs) stand at the forefront of the family. Lowering the coordination number (CN) is an important strategy to improve the performance of Ln-SIMs. Here, we report a theoretical study on a typical group of low-CN Ln-SIMs, i.e. , tetracoordinated structures. Our results are consistent with those of experiments and they identify the same three best Ln-SIMs via a concise criterion, i.e. , the co-existence of long τ QTM and high U eff . Compared to the record-holding dysprosocenium systems, the best SIMs here possess τ QTM values that are shorter by several orders of magnitude and U eff values that are lower by ∼1000 Kelvin (K). These are important reasons for the fact that the tetracoordinated Ln-SIMs are clearly inferior to dysprosocenium. A simple but intuitive crystal-field analysis leads to several routes to improve the performance of a given Ln-SIM, including compression of the axial bond length, widening the axial bond angle, elongation of the equatorial bond length and usage of weaker equatorial donor ligands. Although these routes are not brand-new, the most efficient option and the degree of improvement resulting from it are not known in advance. Consequently, a theoretical magneto-structural study, covering various routes, is carried out for the best Ln-SIM here and the most efficient route is shown to be widening the axial ∠O-Dy-O angle. The most optimistic case, having a ∠O-Dy-O of 180°, could have a τ QTM (up to 10 3 s) and U eff (∼2400 K) close to those of the record-holders. Subsequently, a blocking temperature ( T B ) of 64 K is predicted to be possible for it. A more practical case, with ∠O-Dy-O being 160°, could have a τ QTM of up to 400 s, U eff of around 2200 K and the possibility of a T B of 57 K. Although having an inherent precision limit, these predictions provide a guide to performance improvement, starting from an existing system.

Metal nanoclusters are excellent electrochemiluminescent luminophores owing to their rich electrochemical and optical properties. However, the optical activity of their electrochemiluminescence (ECL) is unknown. Herein, we achieved, for the first time, the integration of optical activity and ECL, i.e. , circularly polarized electrochemiluminescence (CPECL), in a pair of chiral Au 9 Ag 4 metal nanocluster enantiomers. Chiral ligand induction and alloying were employed to endow the racemic nanoclusters with chirality and photoelectrochemical reactivity. S -Au 9 Ag 4 and R -Au 9 Ag 4 exhibited chirality and bright-red emission (quantum yield = 4.2%) in the ground and excited states. The enantiomers showed mirror-imaged CPECL signals at 805 nm owing to their highly intense and stable ECL emission in the presence of tripropylamine as a co-reactant. The ECL dissymmetry factor of the enantiomers at 805 nm was calculated to be ±3 × 10 -3 , which is comparable with that obtained from their photoluminescence. The obtained nanocluster CPECL platform shows the discrimination of chiral 2-chloropropionic acid. The integration of optical activity and ECL in metal nanoclusters provides the opportunity to achieve enantiomer discrimination and local chirality detection with high sensitivity and contrast., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Herein, Fe-doped Co 3 O 4 (Fe-Co 3 O 4 ) was prepared to solve the issues of poor electrical conductivity and the lack of active sites in Co 3 O 4 materials. Due to having similar radius and physical/chemical properties to Co, Fe is an ideal choice for doping Co 3 O 4 , as it can improve intrinsic conductivity without causing severe lattice distortion. Oxygen vacancies are gradually formed as doping reactions occur to maintain electric neutrality. Owing to the merits of oxygen vacancies in Co 3 O 4 , the distribution of the electrons is changed, thus optimizing the material's intrinsic charge/ion states and modifying the band gap by introducing impurity levels. Moreover, the surface area of Fe-Co 3 O 4 is 1.5 times larger than that of the original material. The synergistic effect promotes the electrochemical oxidation reduction reaction and improves the capacitance and cycling stability. Finally, such an advanced Zn//Fe-Co 3 O 4 battery exhibits a discharge-specific capacity of 171.97 mA h g -1 , nearly eight times higher than that of the previous Zn//Co 3 O 4 battery (22.38 mA h g -1 ). In addition, the attenuation of the capacity was almost negligible after 9000 cycles.

Hyperuricemia (HUA) is a systemic disease characterized by a disorder of purine metabolism and an abnormal increase in the serum level of uric acid (UA). Probiotics can exert potential therapeutic benefits against some metabolic diseases by regulating the intestinal microbiota. Lactobacillus fermentum F40-4 with UA-lowering activity of 87.40% was screened using purine as the target in vitro . The UA-lowering activity of L. fermentum F40-4 was further explored in a mouse model of HUA in vivo . L. fermentum F40-4 could downregulate serum levels of UA, blood urea nitrogen, creatinine, and xanthine oxidase by 40.84%, 11.61%, 57.66%, and 41.79%, respectively. L. fermentum F40-4 restored organ damage, and adjusted enzyme activity and transporter expression to promote the metabolic level of UA. In addition, L. fermentum F40-4 could reshape the gut microbiota and suppress inflammation to ameliorate HUA. An increment in intestinal UA excretion was documented. These findings suggest that L. fermentum F40-4 might serve as a potential probiotic for the prevention and treatment of HUA.

Since procalcitonin (PCT) is a specific inflammation indicator of severe bacterial inflammation and fungal infection, it is of great significance to construct a sensitive and rapid microfluidic chip to detect PCT in clinical application. The design of micromixers using a lab-on-a-chip (LOC) device is the premise to realizing the adequate mixing of analytical samples and reagents and is an important measure to improve the accuracy and efficiency of determination. In this research study, we investigate the mixing characteristics of hyperbolic micromixers and explore the effects of different hyperbolic curvatures, different Reynolds numbers (Re) and different channel widths on the mixing performance of the micromixers. Then, an optimal micromixer was integrated into a microfluidic chip to fabricate a desirable hyperbolic microfluidic chip (DHMC) for the sensitive determination of inflammation marker PCT with a limit of detection (LOD) as low as 0.17 ng mL -1 via a chemiluminescence signal, which can be used as a promising real-time platform for early clinical diagnosis.

Based on the bis-β-diketonate-Dy 2 metalloligand [Dy 2 (pbth) 4 ]·2Et 3 N (1, pbth = (3z,3'z)-4,4'-(1,3-phenylene)bis(1,1,1-trifluoro-4-hydroxybut-3-en-2-one)), six dinuclear complexes with eight-coordinated geometries were synthesized solvothermally through different capping N-donor coligands or solvent systems. These complexes are namely [Dy 2 (pbth) 3 (Phen) 2 ]·2C 2 H 5 OH (2), [Dy 2 (pbth) 3 (BPhen) 2 ]·2C 2 H 5 OH (3), [Dy 2 (pbth) 3 (Dppz) 2 ]·2C 2 H 5 OH (4), [Dy 2 (pbth) 3 (Dppz) 2 ]·2CH 3 OH (4a), [Dy 2 (pbth) 3 (4-Dmbp) 2 ]·CH 3 OH·C 2 H 5 OH (5) and [Dy 2 (pbth) 3 (5-Dmbp) 2 ]·CH 3 OH (6) (Phen = 1,10-phenanthroline, BPhen = 4,7-diphenyl-1,10-phenanthroline, dppz = dipyrido [3,2- a :2',3'- c ] phenazine, 4-Dmbp = 4,4'-dimethyl-2,2'-bipyridyl, 5-Dmbp = 5,5'-dimethyl-2,2'-bipyridyl), respectively. In the synthetic processes of 2-6, one of four bis-β-diketonate ligands in the metalloligand is replaced by two capping N-donor coligands. The coordination geometries, metal distances and M-L-M torsion angles of the synthesized complexes are perceptibly fine-tuned by the modification of the capping N-donor coligands or the latticed solvent molecules. Systematic magnetic investigations indicate the different magnetic relaxation dynamics of 1-6. Complex 1 displays no characteristics of single-molecule magnets (SMMs), while complexes 2-6 exhibit SMM behaviours in the absence of a static magnetic field. Complexes 2 and 3 possess effective energy barriers ( U eff ) of 110.18 (2) K and 133.21 (4) K, respectively. Theoretical analysis based on ab initio calculation provides some interpretations of experimental observation.

Exploring the structural evolution of clusters with similar sizes and atom numbers induced by the removal or addition of a few atoms contributes to a deep understanding of structure-property relationships. Herein, three well-characterized copper-hydride nanoclusters that provide insight into the surface-vacancy-defect to non-defect structural evolution were reported. A surface-defective copper hydride nanocluster [Cu 28 (S- c -C 6 H 11 ) 18 (PPh 2 Py) 3 H 8 ] 2+ (Cu 28 -PPh 2 Py for short) with only one C 1 symmetry axis was synthesized using a one-pot method under mild conditions, and its structure was determined. Through ligand regulation, a 29 th copper atom was inserted into the surface vacancy site to give two non-defective copper hydride nanoclusters, namely [Cu 29 (SAdm) 15 Cl 3 (P(Ph-Cl) 3 ) 4 H 10 ] + (Cu 29 -P(Ph-Cl) 3 for short) with one C 3 symmetry axis and (Cu 29 (S- c -C 6 H 11 ) 18 (P(Ph- p Me) 3 ) 4 H 10 ) + (Cu 29 -P(Ph-Me) 3 for short) with four C 3 symmetry axes. The optimized structures show that the 10 hydrides cap four triangular and all six square-planar structures of the cuboctahedral Cu 13 core of Cu 29 -P(Ph-Me) 3 , while the 10 hydrides cap four triangular and six square-planar structures of the anti-cuboctahedral Cu 13 core of Cu 29 -P(Ph-Cl) 3 , with the eight hydrides in Cu 28 -PPh 2 Py capping four triangular and four square planar-structures of its anti-cuboctahedral Cu 13 core. Cluster stability was found to increase sequentially from Cu 28 -PPh 2 Py to Cu 29 -P(Ph-Cl) 3 and then to Cu 29 -P(Ph-Me) 3 , which indicates that stability is affected by the overall structure of the cluster. Structural adjustments to the metal core, shell, and core-shell bonding model, in moving from Cu 28 -PPh 2 Py to Cu 29 -P(Ph-Cl) 3 and then to Cu 29 -P(Ph-Me) 3 , enable the structural evolution and mechanism responsible for their physicochemical properties to be understood and provide valuable insight into the structures of surface vacancies in copper nanoclusters and structure-property relationships., Competing Interests: The authors declare no competing financial interests., (This journal is © The Royal Society of Chemistry.)

NiAl-LDH and CoAl-LDH as typical two-dimensional layered materials have been widely used as supercapacitor cathodes due to their special composition, morphology and rich electrochemically active centers. However, a clear strategy to enhance their electrochemical performances remains lacking. Here, with Ni x Co 3- x Al 1 -LDHs ( x = 1, 1.5 and 2, in short: NiCoAl-LDHs) as examples, a Co/Ni ion co-incorporation strategy was used to study the possible effects on their capacitive performance. Our work demonstrated that different cobalt contents in NiCoAl-LDHs show no obvious changes in their crystal structure, morphology, surface area, etc. However, incorporating more cobalt ions into NiCoAl-LDHs will generate more oxygen vacancies, causing more Ni 3+ ions to appear on the surface, and higher concentrations of Ni 3+ ions and more oxygen vacancies play active roles in enhancing the capacitive performances. The Ni 1 Co 2 Al 1 -LDH electrode with a Ni 3+ /Ni 2+ ratio of 1.44 and an oxygen vacancy concentration of 54.83% delivers a high specific capacitance (728 C g -1 at 1 A g -1 ) and excellent capacitance retention (93.18% of initial capacitance at 30 A g -1 after 10 000 cycles).

The single-molecule magnet (SMM) is a fascinating system holding the potential of being a revolutionary micro-electronic device in information technology. However current SMMs are still far away from real-life application due to their limited performance. Progress towards a performance improvement in SMMs relies on the understanding and then regulation of the magnetic relaxation, which is the microscopical process underlying SMM behaviours. Currently, ab initio electronic structure calculation has become the most popular tool to provide such knowledge, and hence a perspective on its capability and limits is highly valuable. In this work, we make such an attempt based on our research experience with an important constituent of SMM, i.e. , the lanthanide single-ion magnet (Ln-SIM). Besides some fundamental knowledge, we demonstrate what ab initio calculation applied to Ln-SIMs can provide, including both qualitative interpretation and quantitative prediction. The most optimistic expectation is a prediction of the blocking temperature T B with a relative deviation of a few tens of percentages. However we must be aware that reliable assessments of the precision of these results, obtained from ab initio calculation, are crucial to conduct a rational utilization of ab initio calculation in SMMs. Thus, based on our experience and understanding, we also provide such assessments for the sake of being unbiased.

Since cancer has emerged as one of the most serious threats to human health, the highly sensitive determination of cancer cells is of significant importance to improve the accuracy of early clinical diagnosis. In our investigation, a novel cascade Fermat spiral microfluidic mixer chip (CFSMMC) combined with fluorescence sensors as a point-of-care (POC) testing system is successfully fabricated to detect and differentiate cancer cells (MCF-7) from normal cells with excellent sensitivity and selectivity. Here, copper ions (Cu 2+ ) with peroxidase properties can catalyze the oxidation of the non-fluorescent substrate Amplex Red (AR) to the highly fluorescent resorufin (ox-AR) in the presence of hydrogen peroxide (H 2 O 2 ). Subsequently, thanks to the quenching response of AS1411-AuNPs to ox-AR in the microchannel and the binding of AS1411 to nucleolin on the surface of cancer cells, a CFSMMC-based POC system is established for the highly sensitive detection and identification of human breast cancer cells in a "turn on" manner. The change in fluorescence intensity is linearly related to the concentration of MCF-7, ranging from 10 2 to 10 7 cells per mL with a limit of detection (LOD) as low as 17 cells per mL. Interestingly, the cascaded AND logic gate is integrated with CFSMMC for the first time to distinguish cancer cells from normal cells under the control of logic functions, which exhibits great potential in the development of one-step rapid and intelligent detection and logic discrimination.

Over the recent years, intelligent, multi-responsive micelles have received considerable attention due to their promising application in a variety of fields, including biomedical technology, drug delivery, separation, and catalysis. However, the design of such systems with controlled self-assembly is challenging both experimentally and theoretically and is still in the nascent stage. In this study, a novel dual-stimuli triggered wormlike micellar solution is prepared by mixing cationic surfactants 3-hexadecyloxy-2-hydroxypropyltrimethylammonium bromide (R 16 HTAB) and sodium hydrogen phthalate (SHP). The viscoelasticity, aggregate morphology, and pH- and thermo-responsive behavior of the micellar solution are examined by rheological measurements, cryogenic-transmission electron microscopy (cryo-TEM), nuclear magnetic resonance ( 1 H NMR) spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. The dual-sensitive fluid can be switched between a water-like state and a gel-like state by adjusting the pH and temperature. The variations in the flowing behavior are ascribed to the microstructural transition between wormlike micelles, short cylindrical micelles, and spherical micelles. Furthermore, based on the experimental results, dual-responsive behavior of the mixed solution is attributed to the different binding modes between SHP and the surfactant with the variation in the pH and temperature. We hope that the proposed system provides a new route for developing multi-stimuli-responsive materials that are capable of adapting to local environmental variations.

A systematic theoretical study is performed on a group of 16 square antiprism dysprosium single-ion magnets. Based on ab initio calculations, the quantum tunneling of magnetization (QTM) time, i.e. , τ QTM , and effective barrier of magnetic reversal, U eff , are theoretically predicted. The theoretical τ QTM is able to identify the ones with the longest QTM time with small numerical deviations. Similar results occur with respect to U eff too. The systems possessing the best single-molecule magnet (SMM) properties here are just the ones having both the longest τ QTM and the highest U eff , from either experiment or theory. Thus, our results suggest the coexistence of long τ QTM and high U eff to be a criterion for high-performance SMMs. Although having its own limits, this criterion is easy to be applied in a large number of systems since both τ QTM and U eff could be predicted by theory with satisfactory efficiency and reliability. Therefore, this concise criterion could provide screened candidates for high-performance SMMs quickly and, hence, ease the burden of further exploration aiming for a higher degree of precision. This screening is important since the further exploration could easily demand tens or even hundreds of ab initio calculations for a single SMM. A semi-quantitative crystal field (CF) analysis is performed and shown here to be capable of indicating the general trends in a more chemically intuitive way. This analysis could help to identify the most important coordinating atoms for both diagonal and non-diagonal CF components. Thus, it could give some direct clues for improving the SMM properties: reducing the distance of the axial atom to the central ion, rotating the axial atom closer to the easy axis or increasing the amount of its negative charge. Correspondingly, opposite operations on the equatorial atom could give the same result.

The application of supplementary cementitious materials (SCMs) in concrete can improve its durability in the marine environment. Calcium alumino silicate hydrate (CASH) is the main hydration product of SCMs; however, to date, the mechanism of the wetting discrepancy in CASH with different Al/Si ratios has not been revealed at the molecular scale. Herein, the molecular dynamics simulation method was used to study the wettability of water nanodroplets on the surface of CASH substrates with different Al/Si ratios, aiming to reveal the influence of CASH gel with different Al contents on the wettability of water molecules. The simulation results suggested that the CASH interface with a high Al/Si ratio has better wettability for nanodroplets. The microcosmic analysis showed that the interaction between particles and the CASH substrate is affected by the Al content. The electronegativity of the CASH substrate increases due to the substitution of Al-O tetrahedrons, which makes it stronger to solidify Ca ions on its surface and easier to form hydrogen bonds with water molecules in a nanodroplet. The orientation distribution of water molecules further revealed the source of the force of the CASH substrate on nanodroplets at the atomic level. The analysis of the dynamic properties showed that the H-bonds between CASH substrate with a high Al/Si ratio and water molecules are more stable, and thus the nanodroplets have better stability on the surface of CASH.

Ion sensors are attracting attention for real-time ion monitoring in biological fluids, which requires the development of sensitive, stable, flexible, robust and durable ion-selective electrodes (ISEs) and reference electrodes (REs). In this paper, a highly robust and durable ion sensor was prepared by coating polymer membranes on porous carbon electrodes. A high sensitivity of 58.6 mV per decade with a rapid response time of 0.8 s, and a negligible potential drift less than 1.4 mV h -1 were obtained simultaneously. In addition, after six washing cycles, the K + ion sensors still have an average sensitivity of 53.2 mV per decade. Importantly, the polymer membrane permeated and packed the porous structure tightly, and thus the ion sensors presented outstanding robustness and durability. The Nernst slope of the K + ion response fluctuated from 60.2 to 57.9 mV per decade between 0° and 60° bending angles. Repeated bending for 8000 cycles did not result in the delamination of the sensing and reference membranes or reduction of the sensitivity (57.4 mV per decade). Furthermore, five kinds of flexible reference electrodes (LEC, bare Ag, bare Ag/AgCl, PVB + NaCl on Ag/AgCl, PVC/agarose + NaCl on Ag/AgCl) were fabricated and evaluated in terms of the sensitivity for Cl - and long-term stability. Finally, the flexible K + ion sensor was integrated with microfluidic channels and connected to a portable electrochemical workstation to realize the real-time analysis of human sweat.

Six Dy(III) single-ion magnets (SIMs) [Dy( n -OMe-bbpen)X] were synthesized by a solvothermal reaction with three positional isomers ( ortho , meta , and para ) of ligands n -OMe-H 2 bbpen and dysprosium halides DyX 3 , ( n -OMe-H 2 bbpen = N , N '-bis(2-hydroxy- n -methoxybenzyl)- N , N '-bis(2-methylpyridyl)ethylenediamine; n = 3, X = Cl, 1; n = 3, X = Br, 2; n = 4, X = Cl, 3; n = 4, X = Br, 4; n = 5, X = Cl, 5; n = 5, X = Br, 6). Dynamic magnetic measurements revealed that the six complexes possess notably different effective barriers of magnetic reversal: 872.0 K (1), 1210.1 K (2), 137.9 K (3), 602.6 K (4), 907.0 K (5) and 1216.7 K (6). 6 showed the best performance as SIMs among the six Dy(III) complexes. Moreover, the magnetic hysteresis loops of 6 remained open at 21 K. The crystal structures indicate the switching of local symmetry around Dy(III) ion, aroused by the variation in intermolecular interactions and steric effects. This switch is primarily correlated with the distinction of magnetic properties. In addition, ab initio calculations confirmed that the different electrostatic potential around Dy(III) ion stemming from the electronic effect of the OMe-substituted group is another factor leading to the distinction in magnetic properties. This work warns us that when designing ligands for Dy-SIMs, the effect of positional isomerism on magnetic performance must be considered, which is one of the factors that can easily be overlooked.

Flexible wearable electronics play an important role in the healthcare industry due to their unique skin affinity, portability and breathability. Despite great progress, it still remains a big challenge to facilely fabricate stretchable electrodes with low resistance, excellent stability and a wide tensile range. Here, we propose a handy and time-saving strategy for the fabrication of elastomeric films consisting of wave-like fibers with a robust conductive layer of silver nanoparticles (AgNPs) immobilized using polydopamine (PDA) and silicone rubber (SR). To realize better stretchability, electrospun thermoplastic polyurethane (TPU) mats with oriented nanofibers were treated via ethanol to achieve a wavy structure, which also allowed for the decoration of AgNP precursors on the TPU surface via PDA assisted electroless deposition (ELD). Therefore, the electrodes achieved a stretchability of 120% with high electrical conductivity (486 S cm -1 ). The films with a reduction time of 30 min showed superior electrical conductivity indicated by a resistance increase of only 100% within 50% strain. The TPU/PDA/AgNP/SR composites with a shorter reduction time of silver precursors could monitor human motions as wearable strain sensors with a wide work strain range (0-98%) and a high sensitivity (with a gauge factor (GF) of up to 81.76) for a strain of 80-98%. Therefore, they are an excellent candidate for potential application in prospective stretchable electronics.

Controlling the viscoelastic characteristics of wormlike micelles is of great significance to both basic theory and practical applications. In this article, a novel multi-stimuli responsive wormlike micellar solution was prepared by mixing cationic surfactant 3-hexadecyloxy-2-hydroxypropyltrimethylammonium bromide (R 16 HTAB) with trans-o -hydroxycinnamic acid (OHCA). Rheological studies, nuclear magnetic resonance ( 1 H-NMR) spectroscopy, UV-vis spectroscopy, and cryogenic-transmission electron microscopy (cryo-TEM) were utilized to investigate the wormlike micellar system's multi-responsive activity. The results showed that the self-assembled structure and viscoelasticity of the mixed system could be regulated by pH, temperature, and light irradiation. With the increasing trans -OHCA concentration, η 0 of the mixed solution increases first and then decreases and the turning point is presented at 30 mM trans -OHCA, indicating the transformation of spherical micelles to wormlike micelles, and then to short micelles. The microstructure of the mixed systems could be reversibly altered by adjusting the pH between 6.41 and 3.90, which was ascertained by cryogenic-transmission electron microscopy (cryo-TEM). The relationship of temperature and η 0 obeys the Arrhenius law, attributed to the decreasing micellar contour length. η 0 of a 40 mM R 16 HTAB/15 mM OHCA solution sharply increases after UV irradiation, mainly because the cis -isomer could insert into the micelle more easily, and the transition mechanism was studied by UV-vis and 1 H NMR. The multi-responsive self-assembled system may open a new vista for building multi-functional aggregates to adapt to various environmental changes.

Two mononuclear Dy 3+ compounds [Dy(bmbpen-F)X] (X = Cl, 1; Br, 2) with a pentagonal bipyramidal (PBP) geometry were obtained from N , N '-bis-(5-methyl-2-hydroxybenzyl)- N , N '-bis(5-fluoro-2-methylpyridyl)ethylenediamine (H 2 bmbpen-F) and dysprosium halides. The magnetic anisotropy and single-molecule magnet (SMM) behavior of these PBP compounds were regulated by introducing both electron-withdrawing F atoms into the equatorial pyridine rings and electron-donating -CH 3 groups into the axial phenolic hydroxyl rings. The results of magnetic characterization show that 1 and 2 exhibit single molecule magnet behavior with magnetization reversal barriers of 990(13) and 1189(16) K under a zero dc external field and magnetic hysteresis loops up to 26 K and 36 K, respectively. The results of ab initio calculations are consistent with the experimental observations, confirming that the simultaneous introduction of electron-withdrawing groups into the equatorial positions and electron-donating groups into the axial positions can lead to PBP Dy-SMMs with improved properties.

During weaning transition, mammalian newborns suffer severe enteric infections and thus induced gut microbiota dysbiosis, which in turn aggravates enteric disorder. The synthetic dipeptide glycyl-glutamine (GlyGln) has been used as a diet supplement to improve the weaning transition of newborns. However, the effect of dietary GlyGln supplementation on the gut microbiota of piglets with enteric infection remains unclear. Here, weaned piglets received a basal diet or a basal diet supplemented with 0.25% GlyGln for 3 weeks. Five piglets in each group received an intraperitoneal injection of lipopolysaccharide (LPS) (100 μg per kg BW) (LPS and GlyGln + LPS groups) and meanwhile five piglets in a control group received an intraperitoneal injection of saline (Ctrl group). The results showed that dietary GlyGln supplementation improved the LPS induced inflammation response and damage to the ileum morphology by increasing interleukin 10, tight junction proteins, villus height, and the ratio villus height/crypt depth, but decreasing the crypt depth. For the oxidative status, dietary GlyGln supplementation increased the ileal superoxide dismutase and meanwhile reduced the malondialdehyde and nitric oxide synthase activity (NOS) (total NOS and inducible NOS), compared with that in the LPS group. LPS challenge reduced the diversity of gut microbiota and enriched the facultative anaerobic Escherichia coli. The GlyGln restored alpha diversity and the structure of the gut microbiota by enriching obligate anaerobes and short-chain fatty acid (SCFA)-producing bacteria, including Clostridium, Lachnospira, Phascolarctobacterium, Roseburia, Lachnospiraceae, and Synergistetes. GlyGln enriched the gut microbiota function of carbohydrate metabolism and elevated the ileal SCFA concentrations of propionic acid and butyric acid that had been decreased by the LPS challenge. The beneficial effects of dietary GlyGln supplementation are closely associated with its enriched bacteria and SCFAs. Taken together, dietary GlyGln supplementation improved the gut microbiota dysbiosis induced by LPS challenge and enriched obligate anaerobes and SCFA-producing bacteria, which contributed to the amelioration of intestinal integrity, inflammatory responses, and oxidative status.

In this work, a theoretical method, taking into account the anisotropy of the internal magnetic field (B[combining right harpoon above]int), is proposed to predict the rate of quantum tunneling of magnetization (QTM), i.e., τQTM-1, for Kramers single-ion magnets (SIMs). Direct comparison to both experimental and previous theoretical results of three typical Kramers SIMs indicates the necessity of the inclusion of the anisotropy of B[combining right harpoon above]int for accurate description of QTM. The predictions of the method here are consistent with the theory proposed by Prokof'ev and Stamp (PS). For Kramers SIMs of high magnetic axiality, the QTM rates, predicted by the method here, are almost linearly proportional to the results by the PS method. The dependence of τQTM-1 on various parameters is analyzed for model systems. The averaged magnitude of B[combining right harpoon above]int (Bave) and principal g value of the axial direction (gZ) are the parameters on which τQTM-1 is linearly dependent. The ones on which τQTM-1 is quadratically dependent are gXY, i.e., the principal g value of the transversal direction, and xaniso characterizing the anisotropy of B[combining right harpoon above]int. Compared to Bave and gZ, gXY and xaniso provide a higher order of dependence for QTM. Therefore regulation of the SMM property via introduction of desired values of gXY and xaniso ought to be a strategy more efficient than the one via Bave and gZ. Being different from the one via gXY, the strategy via xaniso to regulate the QTM has been rarely touched upon according to our best knowledge. However, this strategy could also lead to significant improvement since it is the same as gXY in the aspect of the dependence of τQTM-1.

A CuH-catalyzed Z-selective partial reduction of alkynyl amides to afford α,β-unsaturated amides using silane as the hydrogen donor is developed. This reaction is carried out under mild conditions and able to accommodate a broad scope of alkynyl amides including those bearing a terminal carbon-carbon double bond or triple bond, affording alkenyl amides with high stereoselectivity and excellent yields.

Solvent responsive magnets comprise a class of molecule-based materials where lattice solvent driven structural transformation leads to the switching of magnetic properties. Herein, we present a special type of magnet where single-crystal to single-crystal (SCSC) transformations within mononuclear DyIII compounds result in the switching of DyIII single-molecule magnets (SMMs). This structural transformation involves lattice solvents which leads to significant changes in the color and magnetic properties. Additionally, the relaxation dynamics of mononuclear DyIII compounds are perceptibly fine-tuned by the modification of β-diketonate ligands. The uniaxial magnetic anisotropies, magneto-structural correlations and the relaxation mechanism were investigated by magnetic studies and ab initio calculations. These experimental and theoretical studies indicate that compound 2 exhibits the best magnetic properties in compounds 1-4. The experimental observation is supported by the theoretical prediction of QTM time (τZeeQTM) as theτZeeQTM of 2 is remarkably longer than those of the other three compounds by an order of magnitude. This means that, compared with 1, 3, and 4, the magnetic relaxation of 2 is significantly slower. Meanwhile, 2 has the largest value of axial ESP (the axial electrostatic potential), which supports the smallest gXY value in these compounds, resulting in better SMM properties. The present results offer a systematic synthesis regulation to change the magnetization dynamics and further understand magneto-structural correlations for DyIII SMMs.

Alloying is an effective tool to comprehend the packing mechanism and adjust the properties of nanomaterials. Herein, two crystal structures of alloy nanoclusters with M 13 icosahedron cores, formulated as [Pt 2 Ag 51 (S-Adm) 28 (PPh 3 ) 2 Cl 7 ](SbF 6 ) 2 and [Au 3 Ag 48 (S-Adm) 28 Cl 7 ](SbF 6 ) 2 , are determined. The preferable site(s) of alloy metals in M 13 induces various packing patterns of M 13 . The Pt 2 Ag 21 and Au 3 Ag 22 kernels are observed in Pt 2 Ag 51 and Au 3 Ag 48 , respectively. The electronic structures of these two nanoclusters are evaluated. Overall, this work presents the effect of alloying on the packing patterns of M 13 and electronic structures of the metal nanoclusters.

A long-term high-fat diet (HFD) leads to significant oxidative stress in the body and induces inflammation. A preliminary evidence suggests a potential therapeutic utility of probiotics for this condition. To evaluate the potential effect of Lactobacillus fermentum DALI02 on the oxidative stress and inflammatory damage induced by HFD, we used a hyperlipidemic rat as a model fed with HFD. Results revealed that HFD induced a significant oxidative stress and inflammation. However, results reveal that L. fermentum DALI02, manifested a significant decrease in levels of malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and resistin, while the catalase (CAT), total antioxidant capability (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and adiponectin (ADPN) levels significantly increased. And it was dose-dependent that the effect of high dose groups with high viable count was particularly notable. The results suggest that L. fermentum DALI02 could alleviate oxidative stress and inflammation as it appeared to reduce lipid peroxidation and improved the lipid metabolism in vivo ., Competing Interests: The authors declare that they have no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Photodynamic therapy (PDT) has been demonstrated to be a promising strategy for the treatment of cancer, while its therapeutic efficacy is often compromised due to excessive concentrations of glutathione (GSH) as a reactive oxygen species (ROS) scavenger in cancer cells. Herein, we report the development of near-infrared (NIR) photothermal liposomal nanoantagonists (PLNAs) for amplified PDT through through the reduction of intracellular GSH biosynthesis. Such PLNAs were constructed via encapsulating a photosensitizer, indocyanine green (ICG) and a GSH synthesis antagonist, l-buthionine sulfoximine (BSO) into a thermal responsive liposome. Under NIR laser irradiation at 808 nm, PLNAs generate mild heat via a ICG-mediated photothermal conversion effect, which leads to the destruction of thermal responsive liposomes for a controlled release of BSO in a tumor microenvironment, ultimately reducing GSH levels. This amplifies intracellular oxidative stresses and thus synergizes with PDT to afford an enhanced therapeutic efficacy. Both in vitro and in vivo data verify that PLNA-mediated phototherapy has an at least 2-fold higher efficacy in killing cancer cells and inhibiting tumor growth compared to sole PDT. This study thus demonstrates a NIR photothermal drug delivery nanosystem for amplified photomedicine.

In this work, a theoretical method for the prediction of both the relaxation time of quantum tunneling of magnetization (τQTM) and the effective barrier of magnetic reversal (Ueff) is proposed for single-ion magnet (SIM) systems of Kramers type. The reliability of theoretical τQTM is tested within a large series of 18 lanthanide SIMs. Compared to the experimental results, the deviations of theoretical τQTM are within one order of magnitude for 11 tested SIMs and the largest order-of-magnitude deviation is only 1.86. In the aspect of Ueff, for 5 typical high-performance Dy-SIMs of the local coordination mode of a pentagonal bipyramid, the relative deviations of theoretical values lie within the range of 1.4-7.2%. Thus this method possesses good reliability, at least in the aspect of the order of magnitude. Besides an empirical estimate of the local magnetic field experienced by the central ion, for a given SIM, one ab initio calculation, providing accurate g-factors of both ground and excited Kramers doublets (KDs), is the only computational cost. Therefore this method has a high degree of both reliability and efficiency. Based on the temperature dependence of theoretically predicted Ueff and its contributions from various KDs, some mechanistic information on the magnetic relaxation could be given by this method too. Therefore it is reasonable to expect the bright prospect of this method in the aspects of both the interpretation of the existing experimental results and rational design of future high-performance SIMs.

A variety of N -unprotected 2-amide-substituted indoles were synthesized from readily available furfural-based Ugi adducts in moderate to good yields via palladium-catalyzed intramolecular cyclization of o -iodoanilines bearing furan rings. These reactions involved a cascade sequence consisting of dearomatizing arylation, opening of the furan ring, and deprotection of the N atom., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Direct C-H functionalization of aryl ethers remains challenging owing to their low reactivity and selectivity. Herein, a novel strategy for nondirected C-H alkenylation of aryl ethers promoted by a dual ligand catalyst was demonstrated. This catalytic system readily achieved the highly efficient alkenylation of alkyl aryl ethers (anisole, phenetole, n-propyl phenyl ether, n-butyl phenyl ether and benzyl phenyl ether), cyclic aryl ethers (1,4-benzodioxan, 2,3-dihydrobenzofuran, dibenzofuran), and diphenyl oxides. Moreover, the proposed methodology was successfully employed for the late-stage modification of complex drugs containing the aryl ether motif. Interestingly, the compounds developed herein displayed fluorescent properties, which would facilitate their biological applications.

Poly(ionic liquid) (PIL), integrating the characteristics of both polymers and ionic liquid, is synthesized and employed to modify diglycidyl-4,5-epoxy-cyclohexane-1,2-dicarboxylate (TDE-85). With the addition of PIL, the fracture toughness, and thermal and dielectric performances of TDE-85 were discovered to be simultaneously improved, meanwhile the tensile modulus and strength is increased. Upon an optimal loading of 3 wt% PIL, the critical stress intensity factor ( K IC ), tensile modulus and strength are raised by 92.9%, 13.3% and 10.7%, respectively. Multi-toughening mechanisms due to spherical domains of PIL formed in TDE-85 during curing are responsible for the improved toughness. Moreover, the dielectric and thermal properties of TDE-85 are also enhanced by adding PIL. With the optimal addition of 5 wt% PIL, the dielectric constant of the composites is enhanced by 62.5%, the glass transition temperature is increased by 16.58 °C and the residual weight of carbon is increased by 59%., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

A family of new structurally manipulable pentagonal-bipyramidal (PBP) Dy III SMMs, with formulas [Dy(Hbpen)(Cl) 3 ] (1), [Dy(Hbpen)Cl(OPhBr 2 NO 2 ) 2 ] (2), [Dy(Hbpen)(OPhCl 2 NO 2 ) 3 ] (3) and [Dy(Mbpen)(Cl) 3 ] (1CH 3 ), were controllably prepared based on a H-substituted amine-based ligand N,N'-bis(2-pyridylmethyl)-ethylenediamine (Hbpen) or a CH 3 -substituted amine-based ligand N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)-ethylenediamine (Mbpen) and are compared with the reported imine-based Dy III analogues (1'-3'). Upon fine-modulating the type of nitrogen donor on the pentagon plane, the electronic effect is efficiently implemented to significantly modify the magnetic anisotropy and SMM behavior of PBP complexes. Notably, the amine-based 2 shows a three-fold improved energy barrier and an observable hysteresis opening up to 3 K. 1 and 1CH 3 exhibit slower relaxation and enhanced anisotropy compared to the imine-based analogue, accompanied by the reorientation of magnetic easy axes. Conversely, poor magnetic properties are observed in 3 after the reduction of imine. The changes in SMM behavior and uniaxial anisotropies are rationalized by both experimental and theoretical studies. The H-substituted amine has formally a larger magnitude of negative charge than imine due to the polarized N-H σ bond. However the repulsion generated by the sp 3 N of amine towards the Dy III ion is also affected by the orientation of lone pair electrons. The present work provides a feasible way to rationally optimize the SMM performance of Dy III complexes, highlighting the importance of the electronic properties of an equatorial donor in controlling the quantum tunneling and the magnetic relaxation of PBP Dy III -SMMs.

Based on systematic DFT calculations, silaborane-based superhalogen anions, which obey the Wade-Mingos rule, are shown to be capable of giving rise to superacids via their combination with protons. Compared to previous carborane-based systems, the acidities of the composites here are stronger in both the gas phase and solution phase. Thus, the potential of candidates based on silaborane could be greater than those based on carborane in the search for ultra-strong acidic systems. Within a given group, a higher superhalogen anion vertical electron detachment energy (VDE) generally leads to stronger acidity. This consistency arises from the dominant role of the VDE, as established through the decomposition of the gas-phase acidity into different contributions. Thus, constructing superacids from superhalogens is a rational route whose future should be positive. Besides the VDE, other effects, i.e., the deformation energy (DE) and bond dissociation energy (BDE), could also be crucial, especially in terms of the differences between the acidities of composites belonging to different groups. A comparison between the results in the gas phase and solution phase indicates that complete calculations of both gas-phase ΔG acid and solution-phase pK a values are necessary to obtain an unbiased description of the acidity. The solvation free energies of the participants in the deprotonation process, especially the conjugate acid, are responsible for the discrepancies between gas phase and solution phase behavior.

A novel carbazole-containing porphyrinoid 4H and its oligomers 6H and 7H were synthesized for the first time via the Suzuki-Miyaura cross-coupling reaction. The structures of 4H, 4Pd, 6H, and 6Zn were finally confirmed by X-ray analysis. The exciton coupling strength (628 cm -1 ) in 4Zn, 6Zn, and 7Zn was found to be larger than that of the directly-linked porphyrin arrays (570 cm -1 ), extending their absorption spectra to the NIR region as well as enhancing the extinction coefficients.