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The stability of luminescent materials is a key factor for the practical application in white light-emitting diodes (LEDs). Poor chemical stability of narrow-band green-emitting RbLi(Li3 SiO4 )2 :Eu2+ (RLSO:Eu2+ ) phosphor hinders their further commercialization even if they have excellent stability against thermal quenching. Herein, we propose an efficient protection scheme by combining the surface coating of amorphous Al2 O3 and hydrophobic modification by octadecyltrimethoxysilane (ODTMS) to construct the moisture-resistant dual-shelled RLSO:Eu2+ @Al2 O3 @ODTMS composite. The growth mechanisms of both the Al2 O3 inorganic layer and the silane organic layer on the phosphor surface are investigated. The results remarkably improve the water-stability of this narrow-band green emitter. The evaluation of the white LED by employing this composite as the green component demonstrates that RLSO:Eu2+ @Al2 O3 @ODTMS is a promising candidate for the high-performance display backlights, and this dual-shelled strategy provides an alternative method to improve the moisture-resistant property of humidity-sensitive phosphors.

Summary Extending the structural hierarchy and complexity through small-molecular self-assembly is a powerful way to obtain large discrete, functional molecular architecture. A hydrogen-bonded supramolecular organic framework (HSOF) with nanometer-size pores is constructed in a solid state with simple guanosine-monomer self-assembly. To extend the hierarchy of the G-quartet self-assembly to a higher order than that of the traditional G-quadruplex, H-bond acceptors on the C-8 position of guanosine are introduced to establish inter-quadruplex linkage via H bonding to N(2)-HB from the neighboring G-quartet. After screening different C-8 substitution groups and various synthesis conditions, HSOF-G1a’ is obtained by solvent evaporation under diluted condition. Single-crystal X-ray structure reveals that cubic repeating units formed by G8 are the supermolecule secondary building block (SBU) with large pores (d = 34 A). To our knowledge, this is the first G-quartet self-assembly with an organized structure beyond cylindrical G-quadruplexes.

Systematic investigations were performed with various substituted groups at C8 purine and ribose. A series of isoG analogs, C8-phenyl substituted isoG were synthesized and applied for Cs+ coordination. The structural proximity between purine and ribose limited pentaplex formation for C8-phenyl substituted isoG derivatives. Based on this observation, deoxy isoG derivative with modification on ribose (tert-butyldimethylsilyl ether) was applied to assemble with the Cs+ cation. Critical solvent (CDCl3 and CD3CN) and anion (BPh4−, BARF−, and PF6−) effects were revealed, leading to the controllable formation of various stable isoG pentaplexes, including singly charged decamer, doubly charged decamer, and 15-mer, etc. Finally, the X-ray crystal structure of [isoG20Cs3]3+(BARF−)3 was successfully obtained, which is the first example of multiple-layer deoxy isoG binding with the Cs+ cation, providing solid evidence of this new isoG ionophore beyond two-layer sandwich self-assembly., The first example of multiple-layer deoxy isoG self-assembly was characterized by X-ray crystal structure. Critical solvent and anion effects were revealed, leading to the controllable formation of various stable isoG assemblies.

In this study, MoS2-graphene-tourmaline (MoS2-GR-T) composite photocatalyst was successful synthesized via one-step hydrothermal method. Raman spectra revealed that graphene oxide was reduced to graphene. Scanning electron microscopy images showed that MoS2 was dispersed well on graphene. Transmission electron microscope images showed that MoS2 and tourmaline contacted well with graphene. Analysis of UV-visible diffuse reflectance spectra implied that the bandgap energies of MoS2, MoS2-T and MoS2-GR-T samples were 2.01 eV, 1.91 eV and 1.79 eV, respectively. The photocatalytic performances are evidenced under Xenon lamp irradiation utilizing Rhodamine B dye as the model compound. Compared with MoS2 and MoS2-GR, the MoS2-graphene-tourmaline (MoS2-GR-T) composites exhibited the excellent photocatalytic activity for the degradation about irradiating for 60 min were 93.9% under visible-light. The enhanced photocatalytic activity of MoS2-GR-T composite could be attributed to the exposed adsorption-photocatalytic active sties, the improved light adsorption ability and the promoted charge separation efficiency. The introduction of tourmaline reduced the band gap explored by analysis of UV-visible diffuse reflectance spectra. This work demonstrated that the charge efficiency of photocatalysts could be promoted by coupling both metal-free co-catalyst and polar mineral.

This study focused on the behavior of heavy metals (HMs) in sewage sludge after conditioning based on total HMs concentration, fractionation and leaching tests. Fe2+-sodium persulfate (SPS) oxidation was applied as chemical conditioner and rice husk (RH) was added as a physical conditioner to improve the dewaterability of sewage sludge. Combined the response surface methodology analysis and our previous research, the capillary suction time (CST) and the water content of sludge cake reduced by 93.8% and 25%, respectively, after conditioned by 125 mg g−1 dry solid (DS) SPS, 33 mg g−1 DS Fe2+, 333 mg g−1 DS RH at original pH of sludge. The HMs analysis indicated that the concentrations of Cu, Pb, Cd, Zn and Cr were increased in liquid phase after conditioning process. And after conditioned by Fe2+/SPS with RH, the leaching toxicity reduction are 79%, 100%, 93%, 80% and 68% for Cu, Pb, Cd, Zn and Cr, respectively. Results showed that RH combined with Fe2+/SPS oxidation has a synergistic effect on risk reduction and immobilization of HMs. The chemical species of HMs were redistributed and the risk of Pb was reduced from medium risk to no risk after sludge conditioning process according to the risk assessment.

Creating ordered metal–organic frameworks (MOFs) membranes with a scalable fabrication for continuous and homogeneous nanoarchitecture represents a category of tunable and functionalizable heterogeneous catalysts. In this work, we demonstrate a facile synthetic strategy for controlling Cu-MOF (1) to fabricate highly oriented MOF membranes (1a) with good controllability in membranes thickness on the macroporous Ni foam as the supporting scaffold, which can promote the growth of the uniform and high-quality MOF-based membranes with the benefit of readily accessible active sites. Nanoscale crystals of 1b also can be acquired by using surfactants as templates without Ni foam as surface-supported. Furthermore, MOFs-based 1–1b have indicated to be efficient heterogeneous catalysts to promote cascade indole acylation–Nazarov cyclization for producing cyclopentenone[b]indoles skeletons. In particular, their unique membrane structure of 1a, containing ordered structure and molecular tunability, affords a well-defi...

Owing to the unpredictable advancement in electronic devices, the demand for highly thermally conductive and electrically insulating material is increasing day by day. Besides, surface treatment of chemically inert hexagonal boron nitride (h-BN) sheets found challenging and a distressing contention towards its acceptable thermal transportation. Herein, h-BN sheets are functionalized with divergent amines (its three isomers) to obtain their astonishing properties like high disperse ability and development of interfacial conduction in polymer composite. This comparative study elucidates the significance of the covalent interaction of amines (-NH2) with h-BN lattice as well as strong hydrogen bonding with thermoplastic polyurethane (TPU) matrix. It is demonstrated that both ortho-phenylenediamine o-PDA-BN and para-phenylenediamine p-PDA-BN filled TPU composites exhibit higher through-plane thermal conductivity (┴TC) of 2.06 and 1.96 W m−1 K−1 respectively by substantially establishing a higher thermal transportation path at high filler loading of 45 wt %. Whereas, meta-phenylenediamine m-PDA-BN composites reveal somewhat low ┴TC of 1.27 W m−1 K−1 at the same filler loading. Interestingly, all fabricated composites consisting of functionalized BN (f-BN) and TPU show unprecedented thermal and mechanical properties at such a high filler loading which demonstrates their great potential for packaging application in microelectronics.

Physical conditioners or skeleton builders are usually used to improve the dewaterability of sewage sludge. In this study, low-cost rice husk (RH) was evaluated as an alternative skeleton builder and combined with Fe2+ and sodium persulfate (SPS) for sewage sludge conditioning. The results show that the sewage sludge conditioned with RH and Fe2+/SPS showed good dewaterability, and the capillary suction time was reduced by 92.8% under optimal conditions. With use of response surface methodology, the optimal composite conditioner concentrations were 151.5 mg/g dry solid (DS) of SPS, 46 mg/g DS of Fe2+, and 333 mg/g DS of RH. After the sludge was conditioned with Fe2+/SPS, some extracellular polymeric substances (EPS) were destroyed, which resulted in the dissolved protein and polysaccharide amounts in the filtrate increasing. The water content analysis indicated the bound water was converted to free water because of the EPS degradation. The particle size analysis showed that the sludge flocs became smaller....

A facile method to fabricate reduced graphene oxide (rGO) and Fe3O4 based composites with enhanced microwave absorption property is prepared by adopting multi-layered structure. The optimal effective bandwidth (EB) reaches 8.4 GHz at 5.2 mm, and optimal reflection loss (RL) value achieves −72.7 dB at 4.5 mm. Comparing with the isotropic single-layered composites with no EB at the same condition, there is a distinct improvement of RL values and EB, demonstrating the positive effects of multi-layered structure on the microwave absorption. The highly improved performances mainly ascribe to the extra interfaces and better impedance match. This work remarkably improves the microwave absorption performance of rGO and Fe3O4 based material through structure adjustment. Besides, we establish an effective and facile path for various materials to enhance their microwave absorption properties by adopting multi-layered structure. The prepared composites can be applied in construction material for microwave absorption and military field for stealth.

Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors with high incidence, rapid progress, and high mortality. There are still some defects in the treatments of OSCC, which seriously affect the quality of patients’ life. Therefore, it is urgent to find a safer and more effective treatment for OSCC. Low molecular weight fucoidan (LMWF) has various biological activities, such as antitumor, anti-inflammatory, and antithrombotic, and has no obvious side effects, but the effect of LMWF on OSCC has not been reported. In this study, the effects of LMWF on dysplastic oral keratinocyte (DOK) and OSCC cells SCC-9 and SCC-25 were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, TUNEL, colony formation, and wound healing assay, and the expression levels of Notch-1 and Jagged-1 treated with LMWF were detected by RT-qPCR. The results showed that LMWF could inhibit the proliferation and migration of DOK and SCC-9, and promote apoptosis. Low molecular weight fucoidan upregulated the expression of Notch-1 and Jagged-1 in DOK and SCC-9 cells. It indicated that LMWF might promote the apoptosis of DOK and SCC-9 by upregulating the Notch signal pathway, thereby inhibiting cell proliferation and playing an antitumor role. It provided theoretical basis to develop LMWF as a novel therapeutic drug for oral cancer.

A rare example of SC-SC triggered by Cu2+ heterogeneous oxidation was demonstrated in a Fe(II)-based MOF {[FeII3(L)2(H2O)6]·3H2O}n (1), which occurred a slow conversion into an oxidized MOF 2 ({[FeIII3(L)2(H2O)6]·3(OH)}n) with retention of single crystallinity. The FeII → FeIII progress of the reaction oxidation was proved by single crystal XRD, PXRD, XPS, 57Fe Mossbauer spectroscopy, and UV–vis. We used 1 and 2 as catalysts to catalyze the tandem Nazarov cyclization, and the results show that acylation products were only harvested when 1 was a catalyst, while the oxidized transformer 2 lead mainly to the formation of cyclization products under identical conditions. Through the test of different substrates, 2 can be a good heterogeneous catalyst candidate for the formation of cyclopentenone[b] benzenes. This work provides a new way to design efficient and hard-synthesized heterogeneous catalyst materials.

Carbon coated hollow mesoporous FeP microcubes derived from Prussian blue were superior in catalytic activity and durability toward electrochemical hydrogen evolution with an overpotential of 115 mV to drive 10 mA cm−2.

Tea saponin of functional ingredients extracted from camellia meal, is China's unique natural functional molecules. With silicone oil containing hydrogen and unsaturated polyether silicon hydrogenation reaction, and then esterification with tea saponin, and the tertiary amine hydrochloride reaction of tea saponin was modified organosilicon quaternary ammonium salt and its conversion rate reached 95%, 90% and 90%, respectively. Discussed the tea saponin in tea saponin modified silicone adjusting agent and quaternary ammonium salt content on the properties of shampoo, used in shampoo, optimum dosage of 0.1 to 0.4% (mass fraction). And tea saponin and quaternary ammonium salt content on the properties of shampoo, it turns out that when n (tea): n (quaternary ammonium salt) = 2.5 ~ 3.5:1, regulate the best performance of shampoo.

Carbon nanotubes (CNTs) have been widely developed for electrochemical energy conversion and storage devices for replacement of high-cost Pt-based catalysts. In this paper, a simple and convenient method is developed for improving the catalytic activity of CNTs in a controlled way. By simple heating treatment in the air, the multi-walled carbon nanotubes (MWCNTs) change with special morphologies, compositions and abundant defects (denoted as h-CNT). Those defects significantly improve the electrocatalytic performances for oxygen reduction reaction (ORR) which proceeds in a nearly four-electron pathway. The heating conditions have important effects on the structures and defect properties of h-CNTs which show a positive correlation between the defect levels and ORR performances. The small amounts of iron residues originated from nanotube growth and nitrogen doping during heating treatment also contribute to some catalytic activity. The inner walls of h-CNT remain intact during heating treatment and provide sufficient conductivity which facilitates charge transport during ORR. The h-CNT electrocatalyst shows better methanol tolerance and long-term durability than commercial Pt/C in alkaline media which makes it an alternative cathode catalyst in fuel cells.

An effective soft template strategy is used for the in situ fabrication of molybdenum-doped mesoporous carbon/graphene composites. As noble-metal-free electrocatalysts for the oxygen reduction reaction in alkaline media, they exhibit excellent catalytic activity through an efficient four-electron-dominant reaction pathway. Observably, compared with commercial Pt/C, they have superior methanol tolerance and long-term stability.

One-step selective benzene acylation-Nazarov cyclization is an attractive, yet challenging method for the synthesis of the benzocyclopentanone skeleton, which is key intermediate of many natural products. Herein, two metal-cluster-based metal-organic frameworks (MCOFs) {(H3 O)2 [Co4 (pbcd)2 (μ3 -OH)2 ]⋅CH3 CH2 OH⋅4 H2 O}n (1; pbcd=9,9'-(propan-1,3-diyl)bis(9H-carbazole-3,6-dicarboxylic acid) and {[Co5.25 (mcd)2 (HCO2 )(μ2 -O)0.5 (μ3 -OH)0.5 (H2 O)4 ]⋅6 H2 O⋅5 DMF}n (2; mcd=9,9'-methylenebis(9H-carbazole-3,6-dicarboxylic acid) were developed to catalyze a tandem Nazarov cyclization reaction of 1,3-dimethoxybenzene with α,β-unsaturated carboxylic acids for the synthesis of cyclopentenone[b]benzenes. MCOFs 1 and 2, which were constructed from tetranuclear CoII cluster [Co4 (μ3 -OH)2 ] and hexanuclear CoII cluster [Co6 (HCO2 )(μ2 -O)(μ3 -OH)], respectively, exhibit high catalytic activity arising not only from their suitable channel size and accessible catalytic sites, but also because of their high density of Lewis acidic sites within the frameworks and the synergic activity among CoII ions. In contrast, {[Co2 (pbcd)(bpe)]⋅2 H2 O⋅2 DMF}n (3; bpe=1,2-bis(pyridin-4-yl)ethane) containing binuclear CoII and having large pore windows is a highly selective catalyst for obtaining exclusively the acylation products. Easy product separation, simple reaction procedures, and catalyst recycling make the catalyst system attractive. This work highlights the synergistic effect among ions of MCOFs in interacting with substrates in a sequential or cooperative manner to achieve tandem catalysis.

A series of solvent-induced Ag-based coordination polymers (CPs) (1-3), which were synthesized by regulating the size, shape, and polarity of solvent molecules (EtOH, iPrOH, 1,4-dioxane) as structure-directing agents, has been used as heterogeneous catalysts to explore how the metal-metal bonds could serve as cooperative catalysis for tandem acylation-Nazarov cyclization reaction to prepare cyclopentenone[b]pyrroles frameworks. Structural conversions from a three-dimensional (3D) framework of 1 to the structure of 2 with Ag-Ag-Ag bonds and to the two-dimensional (2D) framework of 3 with Ag-Ag bonds, arising from the different sizes, shapes, and polarities of the solvent molecules, were observed. Futhermore, the effective cooperative catalysis for tandem acylation-Nazarov cyclization reaction has been evidenced by the significantly transformed connection modes of Ag-Ag interactions in 1-3. As a result, the unique structural characteristics of 2, especially containing the Ag-Ag-Ag bonds, endow 2 with intact multinuclear reaction pathways and well-defined multinuclear platforms that can execute tandem acylation-Nazarov cyclization reaction through the cooperative effect of Ag-Ag-Ag interactions during the catalytic process.

The high price of platinum (Pt)-based cathode catalysts for the oxygen reduction reaction (ORR) have slowed down the practical application of fuel cells. Thanks to their low cost, and outstanding, stable catalytic properties, titanium nitrides (TiN) are among the most promising non-precious metal electrocatalysts for replacing Pt. However, the shape-activity relationships of TiN electrocatalysts have not been well-studied or understood up to now. In this work, by simply adjusting the shape of TiO2 precursor, we are able to tailor the morphology of the TiN catalysts from nanoparticles to nanotubes. We have synthetized uniform carbon-coated titanium nitride nanotubes (carbon-coated TiN NTs) through a nitridation reaction in NH3 flow using a TiO2 nanotubes/melamine mixture as precursor. The carbon-coated TiN NTs hybrids exhibit excellent electrocatalytic activity for the ORR, coupled with superior methanol tolerance and long-term stability in comparison to commercial Pt/C, through an efficient four-electron-dominant ORR process. Compared with nanoparticles, the one-dimensional and hollow structure of the nanotubes result in greater diffusion of electrolyte and superior electrical conductivity, and contribute to the greatly improved electrocatalytic performance of the carbon-coated TiN NTs nanocomposites.

The role of DCP on the space charge performance of XLPE was investigated in this paper. Space charge accumulation characteristics of samples were researched through pulsed electro-acoustic (PEA) and the trapping behavior was studied by surface potential decay (SPD). The results show that the sample without DCP is injected with homo-charges. However, with the increase of DCP concentration, hetero-charges are firstly found and then homo-charges can be found in the samples with higher concentration of DCP. Less space charge as well as more shallow traps can be found in the samples with 1wt% and 1.5wt% DCP. It is indicated that the change of the microstructure and the residues of crosslinking by-products may play a significant role in space charge accumulation and trap formation process in this research.

In our effort to develop coordination polymers (CPs)-based single-site catalysts for the selective synthesis of mono-oxazolines, two Zn-based CPs, [{Zn6 (idbt)4 (phen)4 } ⋅3 H2 O]n (1) and [{Zn3 (idbt)2 (H2 O)4 }⋅2 H2 O]n (2) (H3 idbt= 5,5'-(1H-imidazole-4,5-diyl)-bis-(2H-tetrazole), phen=1,10-phenanthroline) have been synthesized. They exhibit two-dimensional structure and contain isolated and accessible catalytically active sites, mimicking the site isolation of many catalytic enzymes. Micro CPs 1 and 2 are obtained by using surfactant-mediated hydrothermal methods, and an investigation is conducted to explore how different surfactants affect their morphologies and particle sizes. Furthermore, micro 1 and 2 have shown to be effective heterogeneous catalysts for the reaction of amino alcohols and aromatic dinitriles, and exerted a significant influence on the selectivity of the catalytic reactions, yielding mono-oxazolines as the major reaction product.

The development of efficient and low-cost hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalysts for renewable-energy conversion techniques is highly desired. A kind of hollow polyhedral cobalt phosphide (CoP hollow polyhedron) is developed as efficient bifunctional electrocatalysts for HER and OER templated by Co-centered metal-organic frameworks. The as-prepared CoP hollow polyhedron, which have large specific surface area and high porosity providing rich catalytic active sites, show excellent electrocatalytic performances for both HER and OER in acidic and alkaline media, respectively, with onset overpotentials of 35 and 300 mV, Tafel slopes of 59 and 57 mV dec(-1), and a current density of 10 mA cm(-2) at overpotentials of 159 and 400 mV for HER and OER, respectively, which are remarkably superior to those of particulate CoP (CoP particles) and comparable to those of commercial noble-metal catalysts. In addition, the CoP hollow polyhedron also show good durability after long-term operations.

Rapid and sensitive detection of biomarkers with ultralow concentrations remains a great challenge in disease diagnostics. Herein, we present a label-free α-hemolysin (α-HL) nanopore proximity bioassay for protein biomarker detection by a binding-induced DNA strand displacement strategy. In this bioassay, an individual target protein, platelet-derived growth factor B-chain (PDGF-BB), was selectively recognized by two oligonucleotide affinity ligands in which an output DNA was released and translocated through α-HL nanopore with a spikelike short current block. The frequency of the current block events had a linear relationship with the concentration of PDGF-BB with a wide linear dynamic range of 5 orders of magnitude and a detection limit at 500 fM. The selectivity and anti-interference capability of this bioassay show great potential for biomarker detection in bioanalytical chemistry.

A series of N,N’-disubstituted-2-nitroethene-1,1-diamine and N,N’-disubstituted- N’’-cyanoguanidine derivatives were prepared and evaluated for in vivo analgesic activity. The blood brain barrier (BBB) VolSurf model was used to predict the BBB permeation profiles of our synthesized compounds. Some compounds show both remarkable analgesic activity and good BBB permeation profiles, and these compounds might be developed for treatment of opioid tolerance and dependence.

Carbon coated MnO@Mn(3)N(2) core-shell composites (MnO@Mn(3)N(2)/C) were synthesized in a simple approach by calcining MnO(2) nanowires with urea at 800 °C under an ammonia atmosphere. Urea derived carbon nanosheets were partially coated on pure phase MnO@Mn(3)N(2) core-shell composites. Electrochemical measurements reveal that the MnO@Mn(3)N(2)/C displayed high discharge capacities, an excellent high-rate capability and an enhanced cycling performance.