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The development of novel luminescent materials with multi-stimuli responsive and multi-functional properties is required. In this work, we designed and synthesized a novel AIE-based fluorenone derivative, MBPF. The donor–acceptor–donor (D–A–D) structure promoted the intermolecular hydrogen bonding capacity of the exposed oxygen atom in fluorenone. MBPF displayed three different aggregation morphologies: an amorphous floccule Y-MBPF with yellow-green luminescence, a block crystal O-MBPF with orange luminescence, and a needlelike crystal R-MBPF with red emission. They all exhibited reversible stimuli-response phase transitions to temperature and shear, accompanied by fluorescence switching. The orange crystal O-MBPF was also sensitive to isotropic hydrostatic pressure with prominent and contrasting luminescent conversion. Furthermore, we prepared MBPF nanocrystallites and encapsulated them with DSPE–PEG and the monoclonal antibody cetuximab (C225) to obtain MBPF-C225 NPs, which were biocompatible and photostable. They could be used for specific cancer cell imaging through receptor-mediated endocytosis.

Occurrence and flow of hydrocarbons in nanopores are two important issues in the effective exploitation of shale oil reservoirs. In this study, molecular dynamics simulations are employed to investigate the mechanisms about occurrence and flow of octane in slit-shaped quartz nanopores. We show that the occurrence state of octane and, therefore, its flow behavior are profoundly affected by the potential field from quartz walls and adsorption layers if the nanopore width w becomes less than 50 Å. Two main adsorption layers are always formed, adjacent to the walls and independent of w, due to two potential wells generated by the attractive potentials of the walls. Each pair of symmetrical adsorption layers, each of which can be considered as a solid-like surface, forms a confined environment similar to a nano-slit. The attractive potentials from them are found to be the cause for the formation of the adsorption layers between them. The obvious bulk phase of octane is formed in the pore of w = 50 Å due to the wide zero potential barrier induced by the innermost two adsorption layers. The nonlinear dependence of flow rate on pressure gradient shows that Darcy's law fails to describe the flow in the nanopore. The non-Darcy behavior mainly arises from adsorption effects from the walls and the adsorption layers, slippage between octane and walls and between adjacent two adsorption layers, and the molecular exchange between adsorption layers. A modified microscopic model is established to predict the dependence of flow rate on potential field, pressure gradient and w, which is in a good agreement with our simulation results and verified by the dodecane flow through the nanopore. Our work can be of great importance for revealing the mechanisms of occurrence and transport and guiding the estimation and exploitation of shale oil resources.

A series of fully conjugated macrocycles Mn (n = 4–7) consisting of N-(3,5-di-tert-butyl-4-methoxyphenyl) substituted carbazole (Cz-Ar) were successfully synthesized. The aryl carbazole and macrocycle M4 can be readily oxidized and the corresponding radical cation species were found to be highly stable. Moreover, macrocycle M5 was found to form 1 : 1 stoichiometric complexes with fullerenes C60 and C70 with association constants as high as (8.38 ± 0.33) × 104 M−1 and (7.64 ± 0.26) × 104 M−1, respectively.

In this study, Cu(OH)F microspheres suppported on a carbon cloth (Cu(OH)F MS/CC) were rapidly synthesized (at 90 V with 20 min) using an atmospheric dielectric barrier discharge microplasma (DBD). As a multifunctional electrochemical sensor for the detection of glucose (Glu), formaldehyde and hydrogen peroxide, it can accurately detect blood glucose levels in actual serum samples and can determine the contents of formaldehyde and hydrogen peroxide in water samples. Furthermore, it shows good sensitivity and selectivity, which confirmed the feasibility of the Cu(OH)F microsphere electrode for electrochemical sensing. This method was not only rapid and mild (at room temperature and atmospheric pressure) but also provided a promising route for the preparation of nanomaterials for electrochemical sensors.

The intestinal barrier is vital for preventing inflammatory bowel disease (IBD). This study aimed to investigate the potential mechanism behind the protective effects of B. dentium N8 on the intestinal barrier using the lipopolysaccharide (LPS)-induced Caco-2 cells model. Our probiotic validation results showed that B. dentium N8 had a higher adhesion ability and a more substantial inhibition effect on Escherichia coli ATCC 25922 adhesion to HT-29 cells. Regarding the epithelial integrity, B. dentium N8 significantly increased the trans-epithelial electrical resistance (TEER) value and decreased the paracellular permeability of Caco-2 cells stimulated by lipopolysaccharide (LPS). In addition, B. dentium N8 significantly increased ZO-1, occludin, and claudin-1 mRNA expression. B. dentium N8 downregulated the mRNA expression level of TLR4 and pro-inflammatory cytokines (TNF-α, IL-1β, IL-6). Furthermore, B. dentium N8 had a better protective effect on the intestinal barrier than that of E7. Comparative genomics of B. dentium N8 and E7 showed B. dentium N8 had the specific genes encoding for adhesion ability and immune system regulation. The findings provide the theoretical basis for B. dentium N8 possessing a protective effect on the intestinal barrier, which indicate that it could be used as a novel therapy for IBD.

Polyethylene oxide (PEO) and poly(propylene oxide) (PPO), especially their tri-block copolymers PEO-PPO-PEO (poloxamers), have a broad range of applications in biotechnology and medical science. Understanding their specific interactions with biomembranes is the key to unveil the unique features of poloxamers either as membrane-healing or membrane pore-forming agents. Based on the coarse-graining convention of the MARTINI force field and the big multipole water (BMW) model, which has a three charged site topology and can reproduce the correct dipole moment of four-water clusters, we generated coarse-grained (CG) models with analytical and numerical potentials for PEO and PPO homopolymers and poloxamers in dilute solution. The effective bonded interaction potentials between CG beads were determined from the probability distributions of bond lengths, angles and dihedrals that are determined from atomistic simulations. The nonbonded interaction parameters were fine-tuned to reproduce the conformational properties of atomistic PEO and PPO homopolymers and poloxamers via extensive CG simulations of PEO and PPO homopolymers and poloxamers in a BMW water environment. The reported CG models provide a promising framework for a comprehensive understanding of the microstructural, conformational, and dynamic properties of poloxamers and their delicate interactions with other species in an explicit water environment.

The transitions between surfactant aggregate structures are triggered by changes in chemical or physical stimulations, including addition of additives. Effects of added alcohols on aggregate morphologies correlate strongly with alcohol chain length. The local molarities of alcohol, water, and counterions in the interfacial regions play an important role in controlling the aggregate morphologies. However, direct experimental estimates of changes of interfacial alcohol molarities during alcohol induced micelle-to-vesicle transitions have never been reported. Ellipsoidal-wormlike micelle-vesicle transitions in CTAB/KBr aqueous solutions in the presence of long-chain octanol were characterized by using combined rheological, dynamic light scattering (DLS), transmission electron microscopy (TEM) and turbidity measurements. However, the transitions are absent with added butanol. The chemical trapping method (CT) was employed to understand the differences between medium- and long-chain alcohols in determining aggregate morphology. The CT method was used to estimate interfacial water, alcohol, and counterion molarities with increasing stoichiometric alcohol concentrations. With 55 mM alcohol added, the interfacial octanol molarity is 0.9 M, which is three times higher than that for butanol. With added octanol, the ellipsoidal-wormlike micelle-vesicle transition is accompanied by a concurrent sharp increase of interfacial water molarities and a decrease of interfacial counterion molarity, which is not observed with added butanol. The CT data was also employed to estimate the changes of Israelachvili's packing parameter with increasing added alcohol concentration. Our result provides critical molecular level information for understanding the morphological transitions of CTAB/additives.

A catalytic asymmetric synthesis of 3,4-dihydrocoumarins with adjacent tertiary–quaternary stereocenters by 1,6-addition/transesterification cascade reaction of α-isocyanoacetates with ortho-hydroxyphenyl-substituted para-quinone methides (p-QMs) has been developed. Using a combination of dihydroquinidine-derived aminophosphine and silver nitrate as a binary catalytic system, moderate to good yields, excellent diastereoselectivities (>20 : 1 dr) and good to excellent enantioselectivities (up to 94% ee) were achieved for a wide range of isocyanoacetates and p-QMs.

Carrier recombination and charge loss at the interfaces of perovskite layers have a significant influence on high-performance planar perovskite solar cells (PSCs). We employed two-dimensional graphitic carbon nitride (g-C3N4), which is a heat-resistant n-type semiconductor, to modify the electron-transport layer/perovskite and perovskite/hole-transport layer interfaces, respectively. g-C3N4 could passivate the surface trap states of the methylammonium lead iodide light absorber through the formation of a Lewis adduct between N and the under-coordinated Pb, and it could also remarkably reduce the grain boundaries between perovskite crystal particles. A maximum power conversion efficiency (PCE) of 19.67% (Voc = 1.14 V, Jsc = 21.45 mA cm−2, FF = 0.807) could be obtained from planar PSCs with long-term stability using dual-positioned g-C3N4. Therefore, we consider that ultrathin semiconductor films with a Lewis base nature are suitable as dual-functional transport materials for devices. This work provides new guidance for dual-interfacial modification to improve the PCE and stability of devices.

Despite being promising photovoltaic materials, widespread use of organic–inorganic halide perovskite materials is still hindered by their undesirable stability. To cope with this challenge, methylamine (MA) is doped into triple cation perovskite single crystals of (FA0.95−xMAxCs0.05)PbI3, and cesium-containing triple cation perovskite single crystals with five different MA molar ratios (x = 0, 0.05, 0.10, 0.15, and 0.20) are synthesized and characterized. Among them, (FA0.8MA0.15Cs0.05)PbI3 shows high stability against water-oxygen and light for 60 days, and the thermal decomposition temperature of (FA0.8MA0.15Cs0.05)PbI3 reaches as high as 305 °C. Besides, the carrier lifetime of (FA0.8MA0.15Cs0.05)PbI3 is up to 5.957 μs, which remains as 5.646 μs (95%) after 60 days of light illumination. This work studies the stability of perovskite single crystals based on (FA0.95−xMAxCs0.05)PbI3 compositions and provides a reference for the discovery of novel perovskite photovoltaic devices with high efficiency and long-term stability.

Single nucleotide polymorphisms (SNPs) have been proven to be important biomarkers for disease diagnosis, prognosis and disease pathogenesis. Here, taking the advantages of a self-assembled oligonucleotide sandwich structure and robust chemical reactions, we have developed a simple, high-throughput and effective colorimetric analytical technique termed CuAAC-based ligation-assisted assays (CuAAC-LA) for SNP detection using a DNA-BIND 96-well plate. With the 5'-azide and 3'-alkyne groups labelled on two oligonucleotide probes, the target DNA can direct a Cu(i)-catalyzed alkyne-azide cycloaddition (CuAAC) click reaction. Since the small difference in duplex stability caused by a single-nucleotide mismatch was amplified by the steric effects of these reactive groups for the ligation reaction of an unstable duplex, CuAAC-LA exhibited an ultra-sensitive discrimination ability for a mutant type target in the presence of large amounts of wild type targets. As low as 0.05% SNP could be clearly detected, which was better than most previously reported methods by various DNA ligases, indicating that a simple and rapid synthetic method i.e., the DNA template-directed click reaction held the potential to replace the ligase for SNP detection.

The current research involves fabrication of a redox-responsive self-assembly system based on a ferrocene (Fc)-containing β-cyclodextrin (β-CD) derivative (βCD-EG-Fc). βCD-EG-Fc was synthesized, and its redox-sensitive self-assembly behavior was investigated using various techniques. On the basis of the intermolecular host–guest recognition between the β-CD group and the Fc moiety, βCD-EG-Fc primarily formed network-like structures and then vesicles following aging for a specified time. The formation of these structures was primarily driven by hydrogen bonding. Conversely, the oxidized molecules (βCD-EG-Fc+) self-assembled into cationic vesicles with the absence of host–guest complexation. Upon controlling the oxidation and reduction of Fc/Fc+, reversible aggregate transformation was achieved. The current study resulted in a deeper understanding of β-CD/Fc redox-responsive self-assemblies and contributed to the development of a single-component host–guest inclusion model.

Carbazole-based porous organic polymers (CPOPs) and their derived carbon materials have been found to be promising candidates for many applications, such as gas adsorption and energy storage, due to their highly porous structure and nitrogen-containing functionalities. However, most of the reported CPOPs or CPOP-derived carbons are powder-like materials, which limit their industrial applications. Hereby, flexible nitrogen-doped porous carbon materials (FNPCs) were synthesized through in situ oxidative coupling polymerization in/on flexible biomass textiles and subsequent carbonization procedures. During the carbonization procedure, the microporous structure and the nitrogen in CPOPs were maintained. The CPOP-derived FNPCs possess good flexibility and relatively large specific surface area and pore volume, together with high nitrogen contents. In light of these merits, gas adsorption, separation, and preliminary sensing experiments were conducted. The carbon dioxide and methane adsorption capacities of the FNPC are 21.0 wt% and 3.5 wt% (at 273 K and 1.0 bar), respectively. Meanwhile, due to the interaction between CO2 and the FNPCs, the materials can also be used for CO2/N2 separation and gas sensing, and a preliminary experiment on FNPC as a gas sensor for exhaled breath was conducted. More importantly, the materials are flexible and they can be easily assembled into gas adsorption devices and sensors.

An efficient organocatalytic asymmetric tandem conjugate addition-protonation of α-substituted isocyanoacetates to 2-chloroacrylonitrile catalyzed by dihydroquinine-derived thiourea has been investigated, affording the corresponding adducts with two non-adjacent tertiary-quaternary stereocenters in excellent yields (up to 99%) along with good to excellent diastereo- and enantioselectivities (up to 20 : 1 dr, up to 95% ee) under mild conditions. The adduct can also be transformed into chiral γ-lactam by synthetic transformations.

A ruthenium-catalyzed C-H alkenylation of aroylsilanes with electron-deficient alkenes was developed, using acylsilane as the directing group. The mild reaction conditions enable the tolerance of a wide scope of functionalities such as OMe, F, Cl, Br and CF3, providing a convenient and highly effective method for the synthesis of styrene derivatives bearing acylsilane. Steroid and heterocycles such as furan and thiophene were also well tolerated. Furthermore, acylsilane was efficiently converted to the corresponding aldehyde or carboxylic acid.

A facile template-free one-step synthesis method of ultrathin g-C3N4 nanosheets was developed through thermal polycondensation of melamine. The higher temperature, prolonged time and tightly sealed crucible reaction system contributed to the formation of ultrathin g-C3N4 nanosheets. The as-synthesized g-C3N4 nanosheets were applied to the visible light photocatalytic degradation of RhB. The photocatalytic activity was significantly enhanced with increased calcination temperature from 500 °C to 650 °C and prolonged calcination time from 4 h to 10 h. Interestingly, the obtained ultrathin g-C3N4 nanosheets simultaneously possess high yield and excellent photocatalytic activity. Moreover, g-C3N4 nanosheets can maintain photochemical stability after five consecutive runs. The remarkably enhanced photocatalytic activity can be interpreted as the synergistic effects of the enhanced crystallinity, the large surface area, the reduced layer thickness and size and the reduced number of defects. A new layer exfoliation and splitting mechanism of the formation of the ultrathin nanosheets was proposed. This work provides a new strategy to develop a facile eco-friendly template-free one-step synthesis method for potential large-scale synthesis of ultrathin nanosheets with high yield, high photocatalytic efficiency and stable activity for environmental and energetic applications.

Herein, we present the successful preparation of a new family of porphyrin-functionalized coordination star polymers through the combination of coordination-driven self-assembly and post-assembly polymerization. Their ordered self-assembly behaviour in water and potential applications in photodynamic therapy have been demonstrated.

Polysaccharides are one of the major bioactive components in chrysanthemum teas. In order to understand well the chemical structures and bioactivities of polysaccharides from different chrysanthemum teas (JHPs) collected in China, the physicochemical characteristics, antioxidant activity, and antiglycation activity of polysaccharides extracted from different chrysanthemum teas, including Coreopsis tinctoria, Chrysanthemum indicum, C. morifolium ‘Huangju’, C. morifolium ‘Gongju’, and C. morifolium ‘Hangbaiju’, were investigated. The results showed that the contents of total uronic acids and total phenolics in JHPs ranged from (28.4 ± 0.3)% to (36.2 ± 0.2)%, and from 9.4 ± 0.7 to 70.2 ± 1.7 mg GAE per g, respectively. The molecular weights of fraction 1 and fraction 2 in JHPs ranged from 4.29 × 105 to 5.88 × 105 Da, and from 4.11 × 104 to 5.24 × 104 Da, respectively. The dominant constituent monosaccharides of JHPs were galacturonic acid, arabinose, and galactose. Furthermore, JHPs, especially polysaccharides extracted from C. tinctoria, exerted remarkable ABTS, DPPH, nitric oxide, and hydroxyl radical scavenging activities, as well as strong antiglycation activities. The results are helpful for better understanding of the chemical structures and bioactivities of JHPs, and JHPs may have good potential applications in the functional-food industry.

To design highly efficient catalysts for the cleavage of the C–O/C–C bond is the key task in the depolymerization of lignin. Bimetallic alloy catalysts Au–Pd-CTFs were developed to be effective in the oxidative cleavage of β-O-4 lignin model compounds with O2. Au–Pd nanoparticles with an Au/Pd molar ratio between 1 : 1 and 1 : 1.5 showed the highest cleavage efficiency. The kinetics of the reaction process revealed that a synergistic effect between Au and Pd played a crucial role in the oxidation of Cα–OH into CαO, which was the rate-determining step for the whole oxidative cleavage process. Further insight revealed that the cooperative effect between Au–Pd nanoparticles and the support covalent triazine frameworks (CTFs) facilitated the cleavage of the formed β-O-4 ketone compound to the corresponding aromatics. In addition, Au–Pd-CTF catalysts also showed efficiency in the oxidative transformation of the organosolv lignin. This catalytic system will provide guidance in the oxidative cleavage of β-O-4 linkages in lignin.

An efficient organocatalytic asymmetric formal [3 + 2] cycloaddition reaction of α-aryl isocyanoacetates with N-aryl or alkyl substituted itaconimides catalyzed by a dihydroquinine derived squaramide catalyst has been investigated, which affords the corresponding spiropyrroline succinimide derivatives with two non-adjacent quaternary–quaternary stereocenters in moderate to good yields (up to 82%) with moderate to excellent diastereoselectivities (up to >20 : 1 dr) and excellent enantioselectivities (90–>99% ee) under mild conditions.

Uranium is one of the most important elements in the nuclear industry, but it also causes potential health risks to human beings when released into the natural environment. It is highly desired to develop a strategy that enables concurrent uranium detection and adsorption for sustainable development of nuclear energy and environmental conservation. In this work, a fluorescent conjugated microporous polymer consisting of 1,3,5-triethynylbenzene and amidoxime/carboxylate-substituted fluorene (CMPAO) is designed and synthesized for efficient extraction and detection of uranyl ions. The amidoxime ligands on CMPAO provide selective uranium-binding properties, while hydrophilic carboxylate groups largely enhance aqueous dispersibility leading to adequate contact with uranyl ions. As a consequence, CMPAO is capable of selective and efficient extraction of uranyl ions, achieving an optimal sorption capacity of 251.9 mg U g−1. Moreover, the adsorption of uranium on CMPAO leads to dramatic fluorescence quenching, allowing selective and sensitive detection of uranyl ions by fluorescence spectroscopy. Importantly, thanks to the signal amplification by the conjugated skeleton, CMPAO has a fairly low detection limit of 1.7 × 10−9 M for uranyl ions in deionized water, which is far below the maximum contamination standard in drinking water of the World Health Organization (6.3 × 10−8 M).

A platanus-fruit-like manganese monoxide (MnO)/nitrogen-doped porous carbon (MNPC) is prepared by a simple and low-cost method, in which MnO nanoparticles are combined with the polypyrrole-based hydrogel (PPH) derived nitrogen-doped porous carbon (NPC). When used as an electrode, the porous NPC acts as an effective support for the MnO nanoparticles that can provide a high ion storage capacity. Consequently, MNPC shows a good cycling stability and an enhanced rate capability in lithium-ion batteries, and the composite performs better than NPC and bare MnO particles alone. However, in sodium-ion batteries, MNPC exhibits a similar electrochemical behavior as NPC, indicating that MnO nanoparticles are much less active for storing sodium. This is likely because the thermodynamic driving force and redox potential for sodium storage in MnO are much lower than those for lithium storage. Thus, this study helps to thermodynamically reveal the lithiation and sodiation properties of MnO materials.

Facile synthesis of diverse rotaxanes was successfully realized through a simple and efficient supramolecular transformation strategy. Starting from an organometallic [3]rotaxane with a platinum-acetylide moiety as the bridge moiety and transformation site, employing a simple phosphine ligand exchange and sequential reductive elimination reactions resulted in the successful preparation of various rotaxanes with diverse structures and properties.

Covalent triazine frameworks (CTFs) were reported to be effective in the oxidative cleavage of the lignin model compound 2-phenoxyacetophenone, as metal-free catalysts with O2, producing phenol, benzoic acid, methyl benzoate and methyl benzoylformate as the major products. Combining the detailed characterizations with the reaction results, the triazine structure with unique properties of CTFs contributes to their superior catalytic performance. Mechanism investigation, including isotope-labeling, radical trapping and intermediate verification experiments, was carried out. CTFs promoted the decomposition of peroxide and cleavage of both the C–C bond and C–O bond occurred. The catalyst was reusable and very stable under the present reaction conditions. When CTFs were applied to the catalytic oxidative cleavage of organosolv lignin, nearly 80% of β-O-4 ketone bonds of the oxidized lignin were converted, suggesting the potential of CTFs in lignin depolymerization.

Based on the designed π-conjugated aromatic pentacarboxylate of 3,5-di(2′,4′-dicarboxylphenyl)benozoic acid (H5DDB) and bis(imidazole) ancillary linkers (bib = 1,4-bis(imidazol-1-yl)benzene, m-bimb = 1,3-bis(imidazol-1-ylmethyl)benzene, p-bimb = 1,4-bis(imidazol-1-ylmethyl)benzene), five 3D coordination polymers, namely, {Co2(HDDB)(bib)1.5(H2O)2]·H2O}n (1), {[Mn2.5(H2DDB)(HDDB)(bib)0.5(μ2-H2O)(H2O)1.5]·(Hbib)·0.5(H2bib)·0.5H2O}n (2), {[Cd2(HDDB)(bib)1.5(H2O)]·2.5H2O}n (3), {[Cd2(HDDB)(m-bimb)]·H2O}n (4), and {[Cd2(DDB)(p-bimb)]·2.5H2O·0.5(p-H2bimb)}n (5), have been obtained and characterized. Complex 1 is a 3D 3-fold interpenetrating (3,4)-c {83}2{85·9}-vtx net. Based on the binuclear {Mn2(COO)2} SBUs, as well as the trinuclear {Mn3(COO)4(μ2-H2O)2} SBUs, complex 2 shows a 3D 3,4,6-c 3,4,6T10 net with a point symbol of {3·72}2{32·73·8}{32·76·86·10}. Complex 3 displays an unprecedented 3D (3,4,4)-c net with a point symbol of {6·82}2{64·82}2{8·104·12} based on the binuclear {Cd2(COO)4} SBUs. Complex 4 shows an interesting 3D (3,10)-c {410·632·83}{43}2 net based on the quadrilateral tetranuclear {Cd4(COO)8} SBUs. Complex 5 exhibits a linear tetranuclear {Cd4(COO)4} SBU-based 3D (4,10)-c deh1 net with a point symbol of {3·45}2{34·412·510·614·73·82}. A variable temperature magnetic susceptibility investigation indicated that antiferromagnetic interactions exist between the neighbouring metal ions in 1 and 2. Fluorescence measurements showed that 3–5 are promising luminescence sensors for the detection of Cr(VI) anions (CrO42− and Cr2O72− anions) in aqueous solution.

The polymer blend as a modifier for bitumen provides a new route to enhance its rheological properties directly related to service performance. The blending of crystalline polyethylene (PE) and thermoplastic elastomer styrene–butadiene–styrene (SBS) is a good choice for bitumen modification due to the possible combination of excellent rigidity and elasticity originating from PE and SBS, respectively. However, the immiscibility between SBS/PE and either of them with bitumen would make the phase structure evolution complicated. In this paper, the phase structure evolution of bitumen/SBS/PE during annealing is studied by in situ observation under optical microscopy. Two different composition ratios of SBS/PE are chosen to distinguish the role of crystalline polymer and elastomer in the phase structure and rheological behavior. It is found that the phase morphology evolution is mainly dependent on the compositional ratio of polymer blend, which accordingly influences the evolution of SBS-rich droplets. The immersion of SBS-rich droplets into bitumen would effectively enhance the rheological properties in terms of complex modulus and viscosity.

pseudo[1]Catenane 3 is in a self-included conformation in chloroform, but in dichloromethane, it exists in an equilibrium between the self-included conformational state and a de-threading one. The planar chirality inversion of 3 can be triggered by the host-guest complexation of 3 with adiponitrile G, but the extent of such chiral switching depends on the length of self-included bis(pyrazin-2-yloxy)alkane chains in 3 - longer chains are more favored than shorter ones in the inversion.

We have developed an efficient diastereo- and enantioselective Mannich/cyclization cascade reaction of α-substituted isocyanoacetates with 4-aryl-3-carbonyl-1,2,5-thiadiazole-1,1-dioxide type cyclic sulfamide ketimines cooperatively catalyzed by cinchona alkaloid-derived squaramide and AgOAc. The corresponding optically active 2,3,3a,4-tetrahydroimidazo[1,5-b][1,2,5]thiadiazole-1,1-dioxide derivatives were obtained in excellent yields (up to 99%) and good to excellent stereoselectivities (up to >20 : 1 dr, up to 94% ee).

Mono-phosphines (L1 and L2) and diphosphines (L3 and L4) with typical π-acceptor character were prepared and applied in Ir(I)-catalyzed N-alkylation of amines with alcohols. It was found that the π-acceptor character of the applied phosphines is closely correlated to the catalytic efficiency of the [Ir(COD)Cl]2 complex for this green reaction. Compared to PPh3 as the typical σ-donor (i.e. with poor π-acceptor character), L1–L4 all resulted in the efficient N-alkylation of aniline to benzyl-aniline. While L1–L4 coordinated to the Ir(I)-catalyst, the consolidated Ir–P linkages due to π-backdonation could well protect the Ir-catalyst against deactivation, giving rise to the N-alkylation of aniline. On the other hand, the stabilized Ir-catalyst with the involvement of L2 could be recycled successfully for at least 4 runs in the ionic liquid of [MePh3P]Br without the detectable leaching of Ir and P elements in the organic products.

A tripodal fluorescent probe L1 armed with Rhodamine B and 1-naphthaleneisothiocyanates was prepared in high yield. A study of the recognition properties revealed that probe L1 exhibited high sensitivity and selectivity towards Al3+ through a "FRET" fluorescence response and colorimetric response with low detection limits of the order of 10-8 M. Meanwhile, probe L1 also possessed high recognition ability for I- through fluorescence decay, which given there are comparatively few selective fluorescent probes for I-, is significant. Furthermore, the complexation mechanisms were fully investigated by spectral titrations, 1H NMR spectroscopic titrations and mass spectrometry. The utility of probe L1 as a biosensor in living cells (PC3 cells) towards Al3+ ions has also been demonstrated.

In this paper, the graphene oxide (GO) modified by polycarboxylate superplasticizer (PC) (PC@GO) was decorated by silica nanoparticles (SiO2 NPs) to form a hybrid structure of SiO2 NPs/PC@GO. The as-prepared SiO2 NPs/PC@GO hybrid was incorporated in cement matrix for further reinforcement. The results show that SiO2 NPs are uniformly distributed on the surface of GO nanosheets. The addition of SiO2 NPs/PC@GO hybrid (1.5% SiO2 and 0.02% GO by weight of cement) can increase the compressive strength by factors of 38.31%, 44.47% and 38.89% at 3, 7, 28 days, respectively, which are much higher than those of cement composites reinforced by a single-promoter (either PC@GO or SiO2 NPs). Moreover, our results demonstrate that SiO2 NPs/PC@GO hybrid can accelerate the cement hydration, improve the degree of pozzolanic reaction and refine the microstructure of hydration products. The excellent reinforcement is attributed to the synergistic effects of SiO2 NPs/PC@GO hybrid including better dispersion property, higher degree of pozzolanic reaction and cross-linking structure of [SiO2–GO–CSH]. This work provides a very effective way to reinforce cement composites by SiO2 NPs/PC@GO hybrid.

Stimuli-responsive nanocomposite has a great potential application for cell imaging, drug delivery, and improving therapeutic effect. Rare-earth upconversion nanoparticles (UCNPs) have exhibited an excellent properties as a promising biological luminescent labels for fluorescence imaging. In this work, we prepared β-NaLuF4:Yb3+,Er3+ UCNPs coated with thermo-responsive copolymer poly(N-isopropyl acrylamide-co-acrylic acid) (P(NIPAM-co-AA)) by using ligand exchange strategy to obtain novel nanocomposite UCNP@P(NIPAM-co-AA). The acrylic acid moieties of P(NIPAM-co-AA) coordinate with the surfaces of UCNPs, and the PNIPAM moieties can induce the UCNPs dispersion or aggregation in the aqueous solution below and above the lower critical solution temperature (LCST) of PNIPAM. The UCNP@P(NIPAM-co-AA) exhibited weak upconversion luminescence(UCL) fluorescence intensity below the LCST but an 80-fold enhanced UCL intensity at 31 °C above their LCST with only 1 °C temperature transition range. The novel nanocomposite also shows a remarkable reversible property in aqueous solution and low cytotoxicity. For in vitro imaging, a 13-fold signal-to-noise ratio can be obtained below and above the LCST for the novel thermo-activatable UCL imaging, which implies potential application for intelligent biomedical agent.

In this work, hydroxyl-terminated polydimethylsiloxane (H-t-PDMS) nanocomposites reinforced by different contents of graphene oxide nanoribbons (GONRs) were prepared via a facile solvent-free process, and the mechanical properties of the H-t-PDMS/GONR nanocomposites were investigated and compared with the corresponding nanocomposites containing pristine carbon nanotubes (CNTs) or functionalized CNTs (f-CNTs). It was found that the GONRs with abundant functional groups showed good compatibility with the H-t-PDMS matrix at appropriate content: both good dispersion levels of the GONR sheets and strong GONR/matrix interfacial interactions were achieved at low filler content (≤0.5 wt%), although the GONR sheets showed obvious clusters in the matrix at relatively high content. Mechanical testing indicated that the incorporation of a low content of GONRs into the H-t-PDMS polymer resulted in significant improvements in both the tensile and tear strengths, e.g. about 158 and 284% at 0.5 wt% GONRs, respectively; and such reinforcement efficiency of the GONRs in the PDMS nanocomposites was much better than those of the corresponding CNTs or f-CNTs, even superior to those of other carbon nanofillers in previous PDMS-based nanocomposite systems. Based on the morphology and fracture surface analysis, the possible reinforcing mechanisms were discussed and clarified to understand the discrepancies in the mechanical properties of the nanocomposite systems studied.

The wetting behavior of transparent superhydrophobic surfaces has attracted much attention in our daily life as well as in engineering applications. Optically transparent superhydrophobic silica films were synthesized by sol–gel method. The coating was formed by in a solution containing silica nanoparticles and silicic acid, in which the silica nanoparticles and silicic acid had different proportions to modulate the roughness of the coating. Comparing with the HMDZ modified films (140 ± 2°), the films modified by TMCS showed very high water contact angle (164 ± 2°), which indicating the excellent waterproof behavior of the films. When the TMCS modified films were heated at temperature above 350 °C and 400 °C, it became superhydrophilic. The transmittance of coated glasses were above 80% for wavelengths at 400–800 nm. Moreover, the properties of the film were almost unchanged after acid corrosion and immersion in salt solution, and still retained the superhydrophobicity. Even after the impact of water flow and sand impact abrasion, it can still maintain good performance of superhydrophobicity.

The overall objective of this research was the preparation of optical nanocomposite photoanodes through a simple method. The synthesized nanocomposite photoanodes were then used to improve the power conversion efficiency of dye-sensitized solar cells (DSSCs). Titanium dioxide (TiO2) nanofibers (NF) were prepared via electrospinning and calcination. Then, thin films were prepared with commercial TiO2 (NP) as a binder. Different concentrations of zinc oxide (ZnO) nanoparticles were used to impregnate TiO2 NP/NF. When the prepared nanostructures were used as photoanodes, the DSSCs based on NP/NF–ZnO film with an optimum concentration of ZnO (3.5 M) exhibited the highest short circuit current density (Jsc) of 12.83 mA cm−2 and open circuit voltage (Voc) of 0.764 V. The NP/NF–ZnO photoanode also exhibited a maximum power conversion efficiency (PCE) of 6.54%, which was higher by 26.5% than that of NP/NF (5.17%) with the same electrolyte.

A two-dimensional porous framework SHU-1 could undergo solvent-induced structural transformations to SHU-1a in methanol and SHU-1b in water. SHU-1, SHU-1a and SHU-1b showed selective adsorption towards malachite green.

Metal sulfide has received considerable interest for electrochemical energy storage and conversion. However, its inherent poor conductivity and structural instability limit its practical application in energy conversion and storage devices. In this work, Ni3S2 nanoslices anchored on reduced graphene oxide (denoted as Ni3S2@C-RGO) were designed and synthesized through a facile hydrothermal step and a subsequent heating treatment process. Glucose and graphene oxide (GO) both possess abundant oxygenated functional groups, and their strong synergetic effects help to restrict the growth of Ni3S2 to form a nanoslice structure. Meanwhile, the redundant glucose can be transformed into a thin carbon layer coating on the surface of the Ni3S2 slices through the subsequent thermal treatment. When evaluated as the anode of a lithium ion battery (LIB), the synthesized Ni3S2@C-RGO nanocomposite showed an initial capacity of 608.4 mA h g−1, a specific discharge capacity of 560 mA h g−1 remained after the 100th cycle, and improved rate capability, which is much better than that of the Ni3S2 and Ni3S2-RGO nanostructures. The enhanced electrochemical performance can be attributed to the synergetic effects between Ni3S2 nanoslices and the 2D C-RGO nanostructures, such as increasing conductivity, shortening Li+ ion diffusion path, and accommodating huge volume changes through the cycles.

Highly fluorescent non-volatile fluidic fluorene derivatives functionalized with siloxane chains were synthesized and used in monolithic solvent-free liquid organic semiconductor distributed feedback lasers. The photoluminescence quantum yield values, the amplified spontaneous emission thresholds and the ambipolar charge carrier mobilities demonstrate that this class of materials is extremely promising for organic fluidic light-emitting and lasing devices.

A set of pyrene-capped starburst organic emitters composed of a non-planar cross-shaped spirofluorene core (SF-PyF) and a large rigid planar pyrene core (Py-PyF) have been designed, synthesized and explored as efficient emitters for organic lasers. High photoluminescence yields and excellent thermal stability of SF-PyF and Py-PyF in neat films make them promising optical gain media. Low amplified spontaneous emission (ASE) thresholds of 6.6 μJ cm−2 (1.3 kW cm−2) at 451 nm for SF-PyF and 5.4 μJ cm−2 (1.1 kW cm−2) at 490 nm for Py-PyF were obtained (pump pulse: λp = 355 nm, 10 Hz, 5 ns). Distributed feedback (DFB) lasers based on SF-PyF and Py-PyF exhibited good performance with low thresholds (16 nJ per pulse for SF-PyF and 24 nJ per pulse for Py-PyF, respectively) and the full width at half maximum of about 0.2 nm. Surprisingly, DFB lasers integrated with SF-PyF and Py-PyF as gain media exhibited excellent ambient photostability and superior reliability even in hot water (80 °C). The excellent stability of ASE spectra, electroluminescence spectra and lasing spectra under harsh conditions manifests that the resulting pyrene-capped starburst emitters are beneficial for improving the lasing stability issues. The study sheds light on exploring robust organic gain media toward electrically pumped OSLs.

Nanoparticles have the great potential to act as drug delivery carriers, and such systems must effectively deliver the drug to the cancer cells, and provide intracellular drug release. In this research, two types of H+-triggered bubble generating nanosystems (BGNS) were developed which were obtained using hollow mesoporous silica nanoparticles loaded with doxorubicin and subsequently treated with bubble generating agents, i.e., sodium bicarbonate (SBC) and ammonium carbonate (AC). These were named BGNS-SBC and BGNS-AC. After internalization by the tumor cells, the H+ reacts with bicarbonate or carbonate to generate carbon dioxide bubbles quickly in an acidic environment of endo/lysosomes, which results in lysosomal membrane permeabilization (LMP). Then, the enhanced LMP induced cancer cell death by an apoptosis-like pathway because of the release of caspase-3 from the lysosome into the cytoplasm. In addition, BGNS-SBC and BGNS-AC possessed remarkable cytotoxicity against MCF-7 cells and efficiently overcame the multidrug resistance (MDR) of MCF-7/adriamycin cells. Therefore, these bubble generating nanosystems could be a promising nanocarrier for the treatment of tumors.

Glucose-sensitive drug delivery systems, which can continuously and automatically regulate drug release based on the concentration of glucose, have attracted much interest in recent years. Self-regulated drug delivery platforms have potential application in diabetes treatment to reduce the intervention and improve the quality of life for patients. At present, there are three types of glucose-sensitive drug delivery systems based on glucose oxidase (GOD), concanavalin A (Con A), and phenylboronic acid (PBA) respectively. This review covers the recent advances in GOD-, Con A-, or PBA-mediated glucose-sensitive nanoscale drug delivery systems, and provides their major challenges and opportunities.

A series of ionic phosphonium-based aminophosphines L1–L3 were prepared and fully characterized, in each of which the involved bifunctional moieties of the phosphine fragment and Lewis acidic phosphonium were linked together by stable chemical bonds and bridged by one N-atom. The molecular structure of the L2-ligated Rh-complex (Rh-L2) indicated that such bifunctionalities were well retained without incompatibility problems. Investigations on co-catalysis over L1–L3 showed that L3 exhibited the best sequential catalysis for both hydroformylation and acetalization. The phosphine fragment in L3 was responsible for hydroformylation together with the Rh-complex and the phosphonium acted as the Lewis acidic catalyst in charge of acetalization. The L3–Rh(acac)(CO)2 system also exhibited good generality to hydroformylation–acetalization of a wide range of olefins in different alcohols.

The crystal morphology of FOX-7 in different solvents was investigated via molecular dynamics simulations. A modified attachment energy (MEA) model was constructed by introducing surface chemistry terms and the associated topography of the habit crystal plane. Solvent has a large effect on the crystal morphology of FOX-7. The calculated results show that the crystal morphology of FOX-7 in vacuum is dominated by six faces, (0 1 1), (1 0 −1), (1 0 1), (1 1 −1), (0 0 2) and (1 10), while that in acetic acid is dominated by three faces, (1 1 −1), (0 1 1) and (1 0 1). The applicability of the model was successfully validated by the study of FOX-7 crystals grown from cyclohexanone, acetonitrile, H2O/DMF, and H2O/DMSO. All the predicted results are in good agreement with the experimental results. The crystal morphology of FOX-7 is variable in different crystallization solvents. H2O/DMF and H2O/DMSO are good choices for the solvent recrystallization of FOX-7. The results are useful for the formulation design of FOX-7.

A highly efficient and stable Rh–P catalytic system in the RTIL of [PEmim]BF4 was developed for the biphasic hydroformylation of 1-octene by using the diphosphine-functionalized ionic liquid (FIL) of 2. While 2-Rh(acac)(CO)2 was immobilized in [PEmim]BF4 (solvent), a typical biphasic catalysis was fulfilled with advantages of facile separation and recycling ability – 9 runs without any loss of activity. It was found that not only the acquired π-acceptor character of 2, but also the synergetic role of the piperidyl group in [PEmim]BF4 as an N-containing donor, cooperatively contributed to the efficient hydroformylation due to the facilitated formation and stability of the Rh-H active species (ν 2045 cm−1). This was supported by the in situ high-pressure FT-IR spectral analysis.

In this study, we prepared and isolated the pristine endohedral dimetallofullerene Pr2@C72, whose structure was determined to be Pr2@D2(10611)-C72 by a combination of mass spectrometry, UV-visible-near-infrared absorption spectroscopy, and quantum mechanics characterization. Furthermore, we explored the reactivity of Pr2@D2(10611)-C72 using its functionalization by 2-adamantane-2,3-[3H]-diazirine, and the resulting adducts were identified by mass spectrometry and high performance liquid chromatography. Additionally, the preferred addition positions and isomeric structures of the dominant mono-adduct Pr2@C72(Ad) were further investigated using density functional theory.

A novel ionic bi-functional ligand of L2 containing a phosphine and a Lewis acidic phosphonium with I− as the counter-anion was prepared and fully characterized. The molecular structure indicated that the bi-functionalities in L2 were well retained without the incompatibility problem for quenching of the acidity of the phosphonium cation by the Lewis basic phosphine fragment or the anionic I− when the incorporated phosphine fragment and the Lewis acidic phosphonium were strictly located in the confined cis-positions. The co-catalysis over L2–Rh(acac)(CO)2 in the ways of synergetic catalysis and sequential catalysis was successfully fulfilled for one-pot hydroformylation–acetalization, which proved not to be the result of the simple mixture of the mono-phosphine (L4) and the phosphonium salt (L4′). In L2, the phosphonium not only acted as a Lewis acid organocatalyst to drive the sequential acetalization of aldehydes, but also contributed to the synergetic catalysis for the preceding hydroformylation through stabilizing the Rh-acyl intermediate with the phosphine cooperatively. The L2-Rh(acac)(CO)2 system is also generally applied to hydroformylation–acetalization of a wide range of olefins in different alcohols. Advantageously, as an ionic phosphonium-based ligand, L2 could be recycled for 7 runs with Rh(acac)(CO)2 together in RTIL of [Bmim]BF4 without obvious activity loss or metal leaching.

Binding of metal ions to the head of a coordinating amphiphile TTC4L substantially changes the emission color of the terthiophene group attached to the chain end via a conformation triggered self-assembly. This is in analogy with the allostery of proteins in which binding a ligand to one site may affect its performance at another site through conformational change.

A novel metallo-supramolecular micelle PF–SDS–SM was formed at room temperature through the self-assembly of potassium ferrioxalate and sodium dodecyl sulphate. This leads to a new reaction pattern which is not yet fully understood, accompanied by the creation of hollow elongated square microtubular iron oxalate dihydrate during a hydrothermal process.

Human hair, a biowaste composed of protein, is converted into nitrogen and sulfur co-doped porous carbonaceous materials via a facile degradation and carbonization/activation process. The resulting carbon materials possess a large specific surface area value (2700 m2 g−1) as well as high nitrogen and sulfur content (around 8.0 and 4.0 wt%, respectively). The morphology, composition and porous structure of the obtained materials were thoroughly characterized using scanning and transmission electron microscopy, elemental analysis, nitrogen and carbon dioxide sorption analysis, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy, etc. It is confirmed that both the degradation and the carbonization/activation procedures play important roles in the porous structure formation. Furthermore, these materials are proven to exhibit good performances in gas adsorption: carbon dioxide uptake (up to 24.0 wt%, at 273 K and 1.0 bar), methane adsorption (up to 3.04 wt%, at 273 K and 1.0 bar), and hydrogen adsorption (up to 2.03 wt%, at 77 K and 1.0 bar). The high gas adsorption capacities could be attributed to the microporous structure combined with the surface functionalities. In addition, we believe that this synthesis process offers a facile and effective way for transforming protein-containing biowastes into functionalized porous carbonaceous materials.

A novel Pr-based monometallofullerene derivative, Pr@C72(C6H3Cl2), was successfully prepared and isolated. Its molecular composition was determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The molecular structure of Pr@C72(C6H3Cl2) was verified as Pr@C2(10612)-C72(C6H3Cl2) by combined UV-visible-near-infrared absorption spectroscopy and quantum mechanics characterization, as well as a comparison with the structurally characterized analogue La@C72(C6H3Cl2). Furthermore, an additional computation indicated that the nonderivatized Pr@C72 has the lowest-lying structure of Pr@C2(10612)-C72, followed by Pr@C2v(11188)-C72, which lies only 0.62 kcal mol−1 above Pr@C2(10612)-C72. In addition, the temperature dependence of their thermodynamic distribution was estimated. We also analyzed the charge transfer and orbital interaction between the endohedral Pr atom and the carbon cage as well as the electronic configuration and formal charge state of the encapsulated Pr atom based on the computed quantum mechanics data.