A highly sensitive and selective fluorescent probe for rapid detection and intracellular imaging of Pd(II).

A novel near-infrared fluorescent probe (SWJT-13) for detecting Pd2+ ions was designed and synthesized using 3-bromopropargyne group as a recognition site. SWJT-13 can detect Pd2+ ions specifically, which can be quickly recognized by naked eye under natural light. SWJT-13 has a large Stokes shift (155 nm) with LOD of 10.5 nM. The mechanism was verified by 1H NMR, MS, and Gaussian calculations. In addition, the detection of Pd2+ ions by the probe was studied in HeLa cells.

Modified Bamboo Charcoal as a Bifunctional Material for Methylene Blue Removal.

Biomass-derived raw bamboo charcoal (BC), NaOH-impregnated bamboo charcoal (BC-I), and magnetic bamboo charcoal (BC-IM) were fabricated and used as bio-adsorbents and Fenton-like catalysts for methylene blue removal. Compared to the raw biochar, a simple NaOH impregnation process significantly optimized the crystal structure, pore size distribution, and surface functional groups and increase the specific surface area from 1.4 to 63.0 m2/g. Further magnetization of the BC-I sample not only enhanced the surface area to 84.7 m2/g, but also improved the recycling convenience due to the superparamagnetism. The maximum adsorption capacity of BC, BC-I, and BC-IM for methylene blue at 328 K was 135.13, 220.26 and 497.51 mg/g, respectively. The pseudo-first-order rate constants k at 308 K for BC, BC-I, and BC-IM catalytic degradation in the presence of H2O2 were 0.198, 0.351, and 1.542 h-1, respectively. A synergistic mechanism between adsorption and radical processes was proposed.

A Near-Infrared Fluorescent Probe for Recognition of Hypochlorite Anions Based on Dicyanoisophorone Skeleton.

A novel near-infrared (NIR) fluorescent probe (SWJT-9) was designed and synthesized for the detection of hypochlorite anion (ClO-) using a diaminomaleonitrile group as the recognition site. SWJT-9 had large Stokes shift (237 nm) and showed an excellent NIR fluorescence response to ClO- with the color change under the visible light. It showed a low detection limit (24.7 nM), high selectivity, and rapid detection (within 2 min) for ClO-. The new detection mechanism of SWJT-9 on ClO- was confirmed by 1H NMR, MS spectrum, and the density functional theory (DFT) calculations. In addition, the probe was successfully used to detect ClO- in HeLa cells.

A Double-Site Chemodosimeter for Selective Fluorescence Detection of a Nerve Agent Mimic.

A novel two-site chemodosimeter (SWJT-4) based on fluorescein skeleton to detect diethyl chlorophosphate (DCP) was designed and synthesized. It is a turn-on fluorescent probe for DCP with good selectivity and obvious color change in aqueous solution. Interestingly, the two oxime groups of SWJT-4 as dual response sites initiated different reactions with DCP to form a cyano group and an isoxazole ring, respectively. The corresponding mechanism was confirmed by 1H NMR, MS and DFT calculation. Moreover, SWJT-4 could be used as a fluorescent test paper to detect DCP vapor.

Influence of micro-structure on modulation properties in VO2 composite terahertz memory metamaterials.

We have grown VO2 films and combined with terahertz metamaterials to manipulate the memory effect during the insulator-to-metal transition. The temperature-dependent resonant frequency of hybrid structure shows a thermal hysteresis accompanied with frequency shift and bandwidth variation due to the presence of a VO2 dielectric layer. This frequency memory effect significantly depends on the metallic micro-structure. Further theoretical calculation demonstrates this phenomenon mainly originates from the different coupling strength between VO2 and metallic structures. Our findings could facilitate the application of VO2 films in the smart window and dynamical terahertz modulators.

Nanostructured MoO3 for Efficient Energy and Environmental Catalysis.

This paper mainly focuses on the application of nanostructured MoO3 materials in both energy and environmental catalysis fields. MoO3 has wide tunability in bandgap, a unique semiconducting structure, and multiple valence states. Due to the natural advantage, it can be used as a high-activity metal oxide catalyst, can serve as an excellent support material, and provide opportunities to replace noble metal catalysts, thus having broad application prospects in catalysis. Herein, we comprehensively summarize the crystal structure and properties of nanostructured MoO3 and highlight the recent significant research advancements in energy and environmental catalysis. Several current challenges and perspective research directions based on nanostructured MoO3 are also discussed.

Evaluation of three stone-scoring systems for predicting SFR and complications after percutaneous nephrolithotomy: a systematic review and meta-analysis.

BACKGROUND: Clinical studies assessing the feasibility and accuracy of three stone scoring systems's (SSSs: Guy's stone score, CROES nomogram and S.T.O.N.E nephrolithometry scoring system) have reported contradictory outcomes. This systematic evaluation was performed to obtain comprehensive evidence with regard to the feasibility and accuracy of three SSSs. METHODS: A systematic search of Embase, Pubmed, Medline, and the Cochrane Library was conducted to identify studies that compared three SSSs up to Mar 2018. Patients were categorized according to stone free (SF) and no-stone free (NSF), Outcomes of interest included perioperative variables, stone-free rate (SFR), and complications. RESULTS: Ten studies estimating three SSSs were included for meta-analysis. The results showed that SF patients had a significantly lower proportion of male (OR = 1.48, P = 0.0007), lower stone burden (WMD = -504.28, P < 0.0001), fewer No of involved calyces (OR = -1.23, P = 0.0007) and lower proportion of staghorn stone (OR = 0.33, P < 0.0001). Moreover, SF patients had significantly lower score of Guy score (WMD = -0.64, P < 0.0001), but, S.T.O.N.E. score (WMD = -1.23, P < 0.0001) and a higher score of CROES nomogram (WMD = 29.48, P = 0.003). However, the comparison of area under curves (AUC) of predicting SFR indicated that there was no remarkable difference between three SSSs. Nonetheless, Guy score was the only stone scoring system that predicted complications after PCNL (WMD = -0.29, 95% CI: - 0.57 to - 0.02, P = 0.03). CONCLUSIONS: Our meta-analysis indicated that the three SSSs were equally, feasible and accurate for predicting SFR after PCNL. However, Guy score was the only stone scoring system that predicted complications after PCNL.

A Ferrite Synaptic Transistor with Topotactic Transformation.

Hardware implementation of artificial synaptic devices that emulate the functions of biological synapses is inspired by the biological neuromorphic system and has drawn considerable interest. Here, a three-terminal ferrite synaptic device based on a topotactic phase transition between crystalline phases is presented. The electrolyte-gating-controlled topotactic phase transformation between brownmillerite SrFeO2.5 and perovskite SrFeO3- δ is confirmed from the examination of the crystal and electronic structure. A synaptic transistor with electrolyte-gated ferrite films by harnessing gate-controllable multilevel conduction states, which originate from many distinct oxygen-deficient perovskite structures of SrFeOx induced by topotactic phase transformation, is successfully constructed. This three-terminal artificial synapse can mimic important synaptic functions, such as synaptic plasticity and spike-timing-dependent plasticity. Simulations of a neural network consisting of ferrite synaptic transistors indicate that the system offers high classification accuracy. These results provide insight into the potential application of advanced topotactic phase transformation materials for designing artificial synapses with high performance.

High-performance voltammetric sensor for dichlorophenol based on ß-cyclodextrin functionalized boron-doped graphene composite aerogels.

2, 2-methylenebis (4-chlorophenol) (dichlorophenol, Dcp) is a priority pollutant that poses a serious health threat to the public. Thus, the sensitive analysis of Dcp is of great significance. Heteroatom-doped carbon nanomaterials modified electrodes have been proven to be good electrocatalysts for electrochemical sensing application. ß-cyclodextrin (ß-CD) as a signal amplifier has also been utilized in biosensors. Inspired by these, in this study, a new composite of ß-CD and three-dimensional (3D) boron-doped graphene aerogels (BGAs/ß-CD) has been designed as a high-performance electrochemical sensing platform for Dcp determination. Graphene aerogels possess high specific surface area, large pore volume and good conductivity, which ensure rapid mass transfer and accelerated electron transfer. Besides, boron doping causes uneven charge distribution on the graphene lattice surface, producing a large amount of flowing π electrons, which provide abundant active sites for the catalytic oxidation reaction of Dcp. In addition, Dcp molecules could be captured into ß-CD through host-guest recognition, which can effectively amplify the detection signal. Combining the merits of BGAs and ß-CD, the BGAs/ß-CD based sensor achieved sensitive detection of Dcp. Under optimized experimental conditions, the oxidation currents and the concentration of Dcp had a good linear relationship within 1.0 nM âˆ¼ 21 µM. The detection limit was estimated as 0.33 nM (S/N = 3). This study might provide a new basis for the fabrication of 3D BG-based aerogel architectural material and its application in Dcp detection.

Dichloridotetra-kis-(diniconazole)cobalt(II).

In the crystal structure of the title compound, [CoCl(2)(C(15)H(17)Cl(2)N(3)O)(4)], the Co(II) cation lies on an inversion center and has a slightly distorted octa-hedral coordination geometry. The equatorial positions are occupied by four N atoms from four diniconazole [systematic name: (E)-(RS)-1-(2,4-dichloro-phen-yl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pent-1-en-3-ol] ligands. The axial sites are occupied by two Cl(-) anions. In the two independent organic ligands, the triazole ring is oriented at dihedral angles of 18.28 (14) and 32.15 (14)° with respect to the dichloro-phenyl ring. Inter-molecular O-H⋯Cl hydrogen bonds consolidate the crystal packing.

[(E)-(1-Phenyl-ethyl-idene)amino]-urea methanol monosolvate.

In the title compound, C(9)H(11)N(3)O·CH(4)O, the semicarbazone moiety is nearly planar [maximum deviation = 0.017 (2) Å] and is twisted by a dihedral angle of 29.40 (13)° with respect to the phenyl ring. The semicarbazone moiety and phenyl ring are located on opposite sides of the C=N bond, showing the E configuration. An inter-molecular O-H⋯O and N-H⋯O hydrogen-bonding network occurs in the crystal structure.