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A new acceptor unit, fluorinated thieno[2′,3′:4,5]benzo[1,2-d][1,2,3]triazole (fBTAZT), has been designed and synthesized to build two donor–acceptor (D–A) copolymers with the none/fluorinated benzodithiophene (BDT) unit, which have been applied as the electron-donating material with ITIC as an electron-accepting material to fabricate the nonfullerene polymer solar cells (PSCs). It is found that fluorination at the BTAZT unit and BDT unit exerts a significant influence on photophysical properties and photovoltaic performances of the PSCs. As a result, when the fluorine atom is introduced both into the BTAZT unit and the side-chain thiophene ring of the BDT unit, the corresponding polymer PfBTAZT-fBDT exhibits deeper highest occupied molecular orbital–lowest unoccupied molecular orbital energy level and shows stronger interchain interaction with a little broad and red-shift absorption and high charge mobilities as well as good phase-separated morphologies, thus leading to higher power conversion efficiency of 6.59% in nonfullerene PSCs compared with another polymer PfBTAZT-BDT without F atom at the BDT unit, indicating that fBTAZT can be acted as a medium strong organic acceptor to build D–A polymer donor for high efficient PSCs.

In this paper, a deep BiLSTM ensemble method was proposed to detect anomaly of drinking water quality. First, a convolutional neural network (CNN) is utilized as a feature extractor in order to process the raw data of water quality. Second, bidirectional Long Short Term Memory (BiLSTM) is employed to handle the time series prediction problem. Then, a linear combination of t-time-step predictions weighted by a discount factor was utilized to ensemble the final output of event. Finally, cost-sensitive learning combined with Adam optimization was applied to learn the model according to the imbalance property of the event label.

Exploration of the simple and stable coating methods is of great significance in capillary electrochromatography (CEC). In this work, a lysozyme assemble supramolecular membrane coated capillary column was developed for CEC chiral separation. Taking advantage of phase transformation of lysozyme, the coating process was achieved within 1.0 h thus to a large extent reduced the capillary preparation time and simplified the coating procedure. The successful fabrication of the supramolecular membrane coated capillary was verified by scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), fluorescence imaging, and electroosmotic flow (EOF). The separation capacity of the coated capillary was evaluated by analysis of different chiral analytes, including chiral amine drug and neurotransmitters, and good enantioseparation efficiency was achieved for the three pairs of enantiomers. For three consecutive runs, the relative standard deviations (RSD) for the migration time of the analytes for intra-day (n = 3), inter-day (n = 3) and column-to-column (n = 3) were in the range of 0.7–1.5%, 2.7–3.6%, and 4.5–5.8%, respectively. Additionally, the supramolecular membrane coated capillary column could run consecutively 100 times without observable change in the separation efficiency, proving the feasibility of the coating method based on the adhesion of the protein-based supramolecular membrane.

Fluorescent silicon nanoparticles (SiNPs) displayed different emission wavelengths have been synthesized, but it has not been reported that the preparation of wavelength controllable SiNPs by adjusting the nitrogen content of reducing agents. In this paper, the wavelength-controlled fluorescent SiNPs were prepared by selecting the dopamine (DA) with nitrogen content between catechol and 2-aminophenol as the reducing agent and N-[3-(trimethoxysilyl) propyl]-ethylenediamine (DAMO) as the silicon source via one-step hydrothermal method. The emission wavelength of the prepared SiNPs was in direct proportion to the nitrogen content in the reducing agent. To the best of our knowledge, this is the first time for exploring the nitrogen content in reducing agents could affect the optical properties of SiNPs so far. In addition, the obtained SiNPs could be applied to determinate 2-nitrophenol (2-NP). Based on the combination action of inner filter effect (IFE) and static quenching effect (SQE) mechanism, a wide linear range was obtained from 0.1 to 500 μM, and the limit of detection was 0.029 μM for 2-NP, which was comparable to or even lower than some previous reports. This SiNPs probe was also successfully employed for sensing of 2-NP in industrial effluent with satisfactory results (98.6%–103.4%).

An ingenious and viable method for preparing heterogeneous Co

To retrospectively analyze the efficacy and safety of febuxostat on gout patients with low serum uric acid level. A study was conducted in Nanjing First Hospital from October 2015 to September 2016. Thirty nine acute gouty arthritis patients from the emergency and outpatient department were included. Patients met the 2015 Gout Classification Criteria revised by American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) and had urate deposition around the joints detected by dual-energy computerized tomography (DECT). Patients whose serum uric acid (SUA) were between 5.0 and 7.0 mg/dl (300–420 μmol/l) received febuxostat treatment to maintain the SUA level between 3.0 and 5.0 mg/dl for 1 year. Efficacy and safety of febuxostat were observed during the process. Three of 39 subjects were excluded because of adverse events (AEs) after receiving an initial febuxostat treatment for 2 months. Thirty six subjects were enrolled. The mean SUA level was reduced significantly from 6.51 ± 0.28 mg/dl at baseline to 4.24 ± 0.38 mg/dl and SUA of all subjects decreased by 34.8% compared with baseline. After 1-year treatment, the volume of tophus was reduced approximately 62.8%. Serum creatinine decreased stepwise in 8 gout patients with chronic kidney diseases from 162.5 ± 9.2 μmol/l to 131.4 ± 11.0 μmol/l. Two months after initiation of treatment, the number of gout flares began to markedly decrease and almost did not occur after 1 year. After the 1-year treatment of febuxostat, the average SUA level declined significantly, and the renal function improved gradually. There was nearly complete abolition of gout flares by the end of the study. Tophi resolved markedly compared with baseline as assessed by DECT. Furthermore, only a few people experienced adverse events. Febuxostat has a notable effect for gout patients in the lower SUA level range.

Guanosine 3′-diphosphate-5′-di(tri)phosphate (ppGpp) plays a crucial role in the gene expression, metabolism, growth, and other significant processes of microorganisms. In this work, a facile sensitive and visual strategy for the detection of ppGpp has been established by developing a colorimetric probe of copper ions (Cu2+)-mediated 4-mercaptobenzoic acid (4-MBA) modified gold nanoparticles (AuNPs). The sensing process was characterized by transmission electron microscopy (TEM), zeta potential, dynamic light scattering (DLS) and UV-vis spectroscopy. The strategy not only achieves desirable performance over a wide concentration range (0.05–10 μM), but also exhibits excellent selectivity over other nucleotides and biomolecules. In addition, the results could be visualized by the naked eye. We have demonstrated the determination of ppGpp in Bacillus subtilis lysate samples.

In this work, composites with different amounts of graphene oxide (GO) and the copper-based metal–organic frameworks (HKUST-1) were synthesized. They have been applied in chemiluminescence (CL) as catalysts using the luminol–H2O2 system as a CL model for the first time. The results showed that the well-dispersed GO@HKUST-1 (GMs) greatly improved the CL intensity of the luminol–H2O2 system, up to 359-fold. Based on ascorbic acid (AA) inhibiting the CL of the luminol–H2O2–GMs system, a flow injection CL method for monitoring AA was developed. Under the optimized conditions, a good linear relationship was obtained from 0.001 μM to 10 μM, and the detection limit was 0.35 nM. Moreover, the method was successfully used to detect AA in commercial food and fruit juices with satisfactory results. Due to their fascinating features, the GMs would offer a suitable catalytic platform for CL systems and provide potential promise for the construction of CL sensors.

Ischemic stroke is caused when blood flow to the brain is stopped and is a major cause of death and long term disability across the globe. Excessive release of neurotransmitters is triggered in the brain by ischemia that mediates neuronal damage and causes ischemic injury. In this study, a simple, sensitive, and on-line preconcentration capillary electrophoresis method based on electrokinetic supercharging (EKS) was developed for the determination of the biogenic amines including dopamine (DA), epinephrine (E), and norepinephrine (NE) in C57BL/6 mice brain. Under the optimized conditions, the analytes were concentrated and detected within 10 min. The detection limits for the analytes ranged from 0.42 to 0.57 ng mL(-1) for a mice brain matrix. With the proposed method, the analyses of three neurochemical amines in C57BL/6 mice brain tissue during cerebral ischemic/reperfusion had been performed successfully.

An alkali metal selenite chloride, Rb2SeOCl4·H2O, has been hydrothermally synthesized and structurally characterized. It is the first example of an alkali metal selenite halide in the literature. The compound crystallizes in the noncentrosymmetric (NCS) space group, Cmc21(36), of the orthorhombic system with a = 10.342(3) A, b = 10.124(3) A, c = 9.158(3) A, and α = β = γ = 90°. The anionic [SeOCl4]2− groups are arranged in the crystal in nearly the same direction, giving rise to a relatively large macroscopic dipole moment, causing the compound to display second harmonic generation (SHG) eight times as strong as that of KDP, measured using the Kurtz–Perry method on powders. First-principle density functional theory (DFT) calculations were carried out to interpret the relationship between the crystal structure and properties.

We report on a new series “thiophene-free” organic dyes featured with 2,7-disubstituted carbazole as a π-linker for dye-sensitized solar cells (DSSCs). Three different tert-butyl-capped N-arylamine has been introduced as donor group of this series of dyes (coded DH-13 to DH-15 ). These dyes have been systematically characterized and employed in DSSC devices, leading to the power conversion efficiencies of 5.06%, 4.38% and 1.75% for DH-13 , DH-14 and DH-15 , respectively. For a further modification of DH-13 , 2,1,3-benzothiadiazole has been inserted to construct a D-A-π-A structured dye ( DH-16 ) which achieves a power efficiency of 6.76% without coadsorbent that reached 89% of the reference dye N719-based cell. This result indicates that 2,7-disubstituted carbazole could be a promising building block to construct high-performance metal-free organic sensitizer even without most commonly used thiophene derivatives.

A new series V-shaped organic dyes featured with triphenylamine as core/π-linker has been synthesized for the application of dye-sensitized solar cells. Four different polycyclic aromatic subunits have been introduced as donor group in this series of dyes (named DH-6 to DH-9). These dyes have been systematically characterized and employed in DSSC devices. Among the fabricated devices, DH-6-based cell exhibits the highest power conversion efficiency of 4.04% with a short-circuit current density of 8.02 mA cm−2, an open-circuit photo voltage of 0.73 V and a fill factor of 0.69 under AM 1.5 illumination without coadsorbent that reaches 83% of the reference dye N719-based cell. This result indicates that other than electron-donor, triphenylamine could also be a promising π-linker to construct high-performance metal-free organic sensitizer.

In this study, a simple, sensitive, and selective fluorometric platform has been constructed for measuring trypsin in biological samples using the prepared Au–peptide–FITC beacon. The fluorescence of FITC was quenched by Au NPs owing to the FRET mechanism and recovered after selective cleavage of the beacon peptide by trypsin. The calibration plot for trypsin was achieved over the concentration range of 10–100 nmol L−1 with a correlation coefficient of 0.995 and a limit of detection of 5 nmol L−1. In addition, the application of the present approach in determining the trypsin content in blood plasma samples was demonstrated to be satisfactory, which suggested its potential for diagnostic purpose.

In recent years, extensive research has focused on fluorescent carbon nanoparticles (CNPs) due to their excellent photochemical, biocompatible and water-soluble properties. Doping CNPs with heteroatoms provided an attractive means of effectively tuning their intrinsic properties and exploiting new applications in the field of bioimaging and the environment. Herein, nitrogen doped carbon nanoparticles (N-doped CNPs) with a satisfactory quantum yield (36%) were prepared through a facile one-pot and solid-phase synthesis approach. The as prepared N-doped CNPs were relatively monodisperse with a narrow size distribution and uniform surface state. Furthermore, under the optimal conditions, the N-doped CNPs probe was used for the selective and sensitive determination of Hg2+. The limit of detection was 2.3 nM, with a wide concentration linear range of 0.0060–0.9 μM and 0.9–12.0 μM. This simple and green assay was employed for quick detection of Hg2+ in food and cosmetics samples with satisfactory results. The N-doped CNPs was also used as a new type of fluorescent ink due to their strong fluorescence effect and extremely high fluorescent quantum yield.

A low-voltage electro-membrane bioreactor (e-MBR) for fouling alleviation was designed using stainless steel anodes and a membrane module containing titanium cathodes (Fe-MBR). The electric field was applied intermittently once the suction pump was stopped. Compared with another e-MBR with titanium anodes (Ti-MBR) and with one MBR without an electric field, the Fe-MBR had lower transmembrane pressure (TMP), less irreversible fouling and higher pollutant removals under an intermittent voltage of 2.72 V and current of 0.1 A. Coagulation was not obvious because no significant changes were observed in either particle size or zeta potential. The electric field induced backwash was confirmed, by the Ti-MBR, to be effective to suppress fouling. The electric field force might prevent the tight precipitation of foulant on the membrane’s surface and make the fouling layers looser and easier to be removed by aeration. Besides, a strong positive correlation was obtained between fouling indexes and total organic carbon of soluble microbial products (SMPs), suggesting that the reduction of SMPs in the Fe-MBR could have resulted in the fouling depression, and was related to the release of iron. Thus, the joint effects of the electric field force and the release of iron deducted foulant and irreversible fouling, and ultimately lessened the overall fouling. The energy consumption estimation showed 10% more electricity was consumed to make TMP reduce by 30%, indicating the Fe-MBR would be promising in application.

The organic dyes have been synthesized via a ‘Click’ reaction and employed in dye-sensitized solar cells, in which an electron-deficient 1,2,3-triazole unit is introduced to connect the thienyl group and the phenoxyl group as π-linkers. Compared with the non-thiophene containing reference dye, these new dyes show stronger intramolecular charge transfer and higher molar extinction coefficient with incremental increase of thienyl groups. Thus, the short-circuit current of solar cells based on them is greatly increased. Moreover, the existence of 1,2,3-triazole unit is favorable for the charge separation that can retard the charge recombination and improve the open circuit voltage. Consequently, the solar cell based on the dithienyl containing dye presents the best performance with a Jsc of 10.00 mA cm−2, a Voc of 0.68 V and a FF of 0.71, corresponding to an overall conversion efficiency of 4.81% among them.

In this work, it was reported that Cu-BTC (HKUST-1) can excellently catalyze the chemiluminescence (CL) reaction of luminol–H2O2 system in an alkaline medium for the first time. Compared with the luminol–H2O2 system, the CL intensity of luminol–H2O2–HKUST-1 system was enhanced significantly up to about 90-fold, which formed the sensitized CL system. The presence of dopamine (DA) inhibited the luminol–H2O2–HKUST-1 system, thus causing the changes in CL intensity (ΔI). Based on this phenomenon, the excellent sensing platform for detection of DA was established. Under the optimized conditions, the ΔI was proportional to the concentration of DA in the range of 0.010–0.70 μM with the detection limit of 2.3 nM (3S/N). The proposed method was applied to the determination of DA in human plasma and urine samples with satisfactory results. Furthermore, the corresponding mechanism of such enhancement was investigated. The results indicated that the enhancement in CL intensity of the luminol–H2O2–HKUST-1 system originated from the catalysis of HKUST-1, which facilitated the radical generation and electron-transfer processes on its surface.

A good understanding of the mechanism of interaction between quantum dots (QDs) and heavy metal ions is essential for the design of more effective sensor systems. In this work, CE was introduced to explore how l-cysteine-capped-CdTe QDs (l-cys-CdTe QDs) interacts with Hg(2+) . The change in electrophoretic mobility can synchronously reflect the change in the composition and property of QDs. The effects of the free and capping ligands on the system are discussed in detail. ESI-MS, dynamic light scattering (DLS), zeta potential, and fluorescence (FL) were also applied as cooperative tools to study the interaction mechanism. Furthermore, the interaction mechanism, which principally depended on the concentration of Hg(2+) , was proposed reasonably. At the low concentration of Hg(2+) , the formation of a static complex between Hg(2+) and the carboxyl and amino groups of l-cys-CdTe QDs surface was responsible for the FL quenching. With the increase of Hg(2+) concentration, the capping l-cys was stripped from the surface of l-cys-CdTe QDs due to the high affinity of Hg(2+) to the thiol group of l-cys. Our study demonstrates that CE can reveal the mechanism of the interaction between QDs and heavy metal ions, such as FL quenching.

Fluorescence sensing of specific biological molecules by artificial chemosensors is a versatile technique. In the present work, a switch-on fluorescence sensor for rapid, sensitive, and selective sensing of glutathione (GSH) in food samples was developed. This method was based on the g-CNQDs–Hg2+ system, in which the initial fluorescence from g-CNQDs was quenched by Hg2+ with an electron transfer process. In the presence of GSH, the fluorescence sensor was switched to the “on” state, which was attributed to a competitive affinity of Hg2+ to GSH and the functional groups on the surface of g-CNQDs. Under the optimal conditions, the limit of detection (LOD) of 37 nM for GSH was achieved with a wide range of 0.16–16 μM. The repeatability was better than 5.3% for GSH in both standard and food samples (n = 3). Finally, this fluorescence sensor was successfully employed for the determination of GSH in various kinds of food samples with excellent recoveries. Furthermore, this application may pave a new way for fl...

We developed a colorimetric sensor based on gold nanoparticle (AuNP) labels and target-triggered strand displacement amplification (SDA) for the detection of platelet-derived growth factor-BB (PDGF-BB). Upon the target binding, the linear probe conformation was converted into a triple-helix conformation and then a large number of reporter oligonucleotides were produced by SDA. PDGF-BB was then determined by detecting the reporter oligonucleotides using gold nanoparticle labels. The signal output showed a linear relationship for PDGF-BB within the concentration range from 2.0 to 80 nM with a detection limit of 1.1 nM under the optimal conditions. An obvious AuNPs color change was provided when the concentration of PDGF-BB was as low as 4.0 nM. Notably, the assay demonstrated here was free from the interference of other proteins commonly existing in the human breast cancer tissue extracts.

Using an ion-substitution strategy, herein, a new polar material, Pb

Exploring gene-disease associations is of great significance for early prevention, diagnosis and treatment of diseases. Most existing methods depend on specific type of biological evidence and thus are limited in the application. More importantly, these methods ignore some inherent prior sparsity and structure knowledge which is useful for predicting gene-disease associations. To address these challenges, a novel Enhanced Inductive Matrix Completion (EIMC) model is proposed to predict pathogenic genes by introducing the prior sparsity and structure knowledge into the traditional Inductive Matrix Completion (IMC). Specifically, the EIMC model not only employs the sparse regularization to preserve the prior sparsity of gene-disease associations, but also employs the manifold regularization to capture the prior structure information of data distribution. To the best of our knowledge, the proposed EIMC is the first model to simultaneously incorporate both prior sparse and manifold regularizations into the same objective function. Additionally, note that our proposed EIMC model also integrates the features of genes and diseases extracted from various types of biological data, and can predict new genes and diseases by using an inductive learning strategy. Finally, the extensive experimental results demonstrate that our proposed model outperforms other state-of-the-art methods.

PM\(_{2.5}\) is a crucial indicator of haze pollution, which can cause problems in respiratory systems. Accurate PM\(_{2.5}\) concentration forecasting systems are essential for human beings to take precautions. State-of-the-art methods including support vector regression (SVR), artificial neural network (ANN) and Bayesian, try to forecast PM\(_{2.5}\) concentrations of the following 3 days via building an approximation from weather features to PM\(_{2.5}\) concentration. However, the performances of these methods are poor because they ignore the essence of the problem: PM\(_{2.5}\) concentration is the product of a time series.

In this paper, a simple one-pot hydrothermal procedure to create three-dimensional (3D) graphene/multiwalled carbon nanotubes/Pd (G/MWCNTs/Pd) composite hydrogels with a unique porous nanostructure was reported. During the formation of the G/MWCNTs/Pd composites, 2D graphene sheets and 1D MWCNTs were self-assembled to form interconnected porous microstructures and ultrafine Pd NPs were in situ grown on the 3D carbon-based skeleton simultaneously. In the as-obtained nanocomposites, MWCNTs not only prevented the close restacking of graphene sheets to increase the specific surface area but also provided an additional transport path to the catalyst surfaces which facilitated reactant transport. The G/MWCNTs/Pd composites proved to be an efficient, recyclable, and robust catalyst for the Suzuki cross-coupling reactions under mild aerobic conditions, which was attributed to the 3D macroporous framework with high specific surface area, numerous activation sites, and efficient transport pathways for improving the catalytic performance. Moreover, catalyst separation could be easily achieved by simple filtration, and the catalyst could be reused for at least six runs without significant loss in catalytic activity. Additionally, nearly no Pd species was released from the G/MWCNTs/Pd composites during the catalytic reactions, showing the heterogeneity in the present catalysis system.

We developed a synthetic strategy for enhancing organic thin-film transistor performances of polymer semiconductors through the modification of the side chain to optimize the stacking conformation and the conjugated backbone to decrease the π–π stacking distance of polymers. Our studies demonstrate that the role of bulky alkyl chains attached to the donor unit or the acceptor unit is especially crucial for molecular stacking and aggregation and thus the OTFT device performance of polymers. However, with a larger π–π stacking distance in the thin film, the polymer with a bulky alkyl chain attached at the acceptor (P2) shows almost two orders of magnitude higher mobility than that with a bulky alkyl chain attached at the donor (P1). The better performance for P2 is attributed to the bulky alkyl chain at the acceptor which allows more coplanarity of the P2 backbone in the solution state, which leads to self-assembly, and finally forms a highly ordered layer-by-layer lamellar packing for P2 during spin-coating. Further improved performances were obtained by introducing two thiophene units into the polymer backbone to give P3, due to closer π–π stacking and in-plane π-stacking alignment in the thin film and a higher HOMO energy level. Therefore, an optimized device performance was realized through subtle modification of the polymer structure, including both the main chain and the side chain, which provides an insight into structure–property relationships for high-mobility polymer semiconductors.

MFe 2 O 4 (M=Mg, Ni, Cu) magnetic nanoparticles (MNPs) were found to have catalytic activities similar to those of biological enzymes such as catalase and peroxidase. These nanomaterials, as bifunctional catalase/peroxidases (KatGs), not only could catalyze H 2 O 2 to produce hydroxyl radicals, which oxidized peroxidase substrate to produce color, but also could catalyze the decomposition reaction of H 2 O 2 into water and oxygen directly in the same condition through the catalase-like activity. And it was also found that the amount of generated hydroxyl radicals and oxygen was related to the concentration of MFe 2 O 4 (M=Mg, Ni, Cu) MNPs. The peroxidase-like catalytic behavior of MFe 2 O 4 MNPs was analyzed in detail. Under the optimized conditions, NiFe 2 O 4 MNPs were used as a colorimetric biosensor for the detection of 9.4×10 −7 –2.5×10 −5 mol L −1 glucose with a limit of detection (LOD) of 4.5×10 −7 mol L −1 . The sensor was successfully applied to glucose detection in urine sample.

Two new D–π–A organic dyes containing a tert-butyl-capped indolo[3,2,1-jk]carbazole unit as a donor, bithiophene unit as a π-linker and cyanoacrylic acid as an acceptor (CL-10 and CL-11) have been designed and synthesized for dye-sensitized solar cells (DSSCs). By comparison, two dyes exhibit almost the same absorption and electrochemical properties, because the introduction of two hexyl groups at non-ortho β-positions of the 2,2′-bithiophene unit dose not destroy the planarity of the molecular skeleton of CL-11. However, the DSSC devices based on them show very different photovoltaic performances with power conversion efficiency (PCE) of 3.96% for CL-10 and 2.85% for CL-11, which can be attributed to the existence of the hexyl groups in CL-11 that lead to a big decrease of the dye adsorption onto TiO2. The addition of chenodeoxylic acid (CDCA) as a coadsorbant can significantly improve the photovoltaic performances of the DSSCs with a big increase in the PCE for CL-10 (4.68%) and CL-11 (4.66%).

In this paper, core–shell polydopamine (PDA)-encapsulated CuFe2O4 (CuFe2O4@PDA) magnetic nanoparticles (MNPs) were synthesized through in situ self-polymerization for the first time. The size of the core–shell product can be controlled by tuning the dopamine monomer concentration. The formation of a PDA layer effectively enhanced the catalytic performance and provided a large specific surface area which offered more active sites for the effective interaction. The as-synthesized CuFe2O4@PDA MNPs were characterized and their catalytic activity was evaluated using the degradation of methylene blue (MB) in the presence of H2O2 as a model reaction. The experimental results showed that MB could be degraded efficiently using CuFe2O4@PDA MNPs as a catalyst. Under the optimized conditions, the degradation efficiency of MB was above 97%. Furthermore, a possible reaction mechanism was discussed. Finally, the catalyst was used for effective degradation of MB in a Yellow River water sample, which indicates its potential for practical applications in water pollutant removal and environmental remediation.

In this work, a facile and highly efficient on-line concentration strategy based on a coupling of field enhanced sample injection (FESI) and sweeping was developed for the determination of trace enantiomers (propranolol, PL) by nonaqueous capillary electrophoresis (NACE). In this FESI-sweeping method, the use of a sample of high acidity and low conductivity (pH* = 2.5, 4.0 μS cm(-1)) allowed for a large amount of analyte injection. Then, the concentration of the analytes was carried out by sweeping based on the interaction of an acid-labile anionic selector, di-n-butyl L-tartrate-boric acid complex acid, and cationic analytes. Simultaneously, the concentrated analytes were released and focused at the boundary of the acid sample solution and separation buffer due to the decomposition of the selector in the acid sample solution. Under the optimum conditions, a 21,000-fold sensitivity enhancement upon normal capillary zone electrophoresis (CZE) was achieved for PL enantiomers. The detection limits of R-propranolol and S-propranolol were 0.26 ng mL(-1) and 0.31 ng mL(-1), respectively. Eventually, the FESI-sweeping method was applied to detect PL enantiomers in plasma, saliva, and urine.

A novel thiophene-fused diketopyrrolopyrrole unit (7H-pyrrolo[3,4-a]thieno[3,2-g]indolizine-7,10(9H)-dione, PTI) has been designed as an electron acceptor with the 4,4′-bis-(2-ethylhexyl)-dithieno[3,2-b:2′,3′-d]silole (DTS) unit as a donor to construct a new kind of A–D–A molecule (DTS–2TPTI) for solution-processed solar cells. DTS–2TPTI exhibits excellent thermal stability with the decomposition temperature over 400 °C and shows strong absorption from 550 to 750 nm with a high molar extinction coefficient. The optical band gap (Eg) estimated from the absorption edge of the thin film is about 1.44 eV. The highest occupied molecular orbital energy level of DTS–2TPTI determined from CV is about −4.99 eV. Through optimizing the photovoltaic performances of devices, the DTS–2TPTI/PC71BM-based solution processed bulk-heterojunction solar cell with 0.5% DIO as a solvent additive exhibits the best photovoltaic performance with a JSC of 11.28 mA cm−2, VOC of 0.64 V, FF of 59.5% and power conversion efficiency (PCE) of 4.28%, indicating that the PTI unit can act as an efficient acceptor moiety to construct D–A small molecules for OPVs.

To search for a new nonlinear optical (NLO) material to be used in the mid-IR region with excellent comprehensive performance including high laser damage threshold (LDT), K2SbF2Cl3 has been synthesized by the hydrothermal method, and its potential as such a new material is evaluated for the first time. Its powder shows phase-matchable second harmonic generation (SHG) response of approximately 4 times as strong as that of KH2PO4 (KDP). Its optical band gap is 4.01 eV, which is much wider than the band gaps of the currently commercialised IR NLO crystals. This means that K2SbF2Cl3 will exhibit a much higher LDT. Its powder also exhibits excellent transparency in the range of 0.31–14 μm and good thermal stability. The relationship between the composition, crystal structure and properties is discussed. These results indicate that K2SbF2Cl3 is a promising candidate for IR NLO materials.

The present study aimed to investigate the role and mechanism of microRNA-539 (miR-539) in rheumatoid arthritis (RA). A total of 68 RA patients and 46 osteoarthritis patients were enrolled into the current study. Peripheral blood and joint fluid were collected prior to treatment. Reverse transcription-quantitative polymerase chain reaction was performed to detect osteopontin (OPN) mRNA and miR-539 expression levels, while ELISA and western blot analysis were applied to detect OPN protein expression. In addition, bioinformatics analysis predicted that miR-539 directly targeted OPN, while dual-luciferase assay was used to validate this finding. Furthermore, agomiR-539 transfection and OPN knockdown by siRNA were conducted in MH7A cells, and MTT assay was used to detect MH7A cell proliferation. The results indicated that OPN was significantly increased in the blood and joint fluid of RA patients, while miR-539 expression was significantly decreased in the two types of specimens (P

As we know, hexavalent chromium (Cr(VI)) was usually used as an additive to improve the color fastness during the printing and dyeing process, and thus posing tremendous threat to our health and living quality. In this work, the dual emissive carbon dots (DECDs) were synthesized through hydrothermal treatment of m-aminophenol and oxalic acid. The obtained DECDs not only exhibited dual emission fluorescence peaks (430 nm, 510 nm) under the single excitation wavelength of 380 nm, but also possessed good water solubility and excellent fluorescence stability. A ratiometric fluorescent method for the determination of Cr(VI) was developed using the DECDs as a probe. Under the optimal conditions, a linear range was obtained from 2 to 300 μM with a limit of detection of 0.4 μM. Furthermore, the proposed ratiometric fluorescent method was applied to the analysis of Cr(VI) in textile, steel, industrial wastewater and chromium residue samples with satisfactory recoveries (88.4–106.8%).

In recent years, artificial materials with double helix structure have attracted widespread attention due to their unique properties such as the DNA like double-helicity, intrinsic chirality and diverse functional groups. Developing novel chiral stationary phases (CSPs) for capillary electrochromatography enantioseparation is of intriguing interest. Herein, a novel homochiral zeolite-like metal-organic framework (ZMOF) JLU-Liu23 with unique DNA like double-helicity structure was firstly utilized as the CSP in open tubular capillary electrochromatography (OT-CEC) for enantioseparation of chiral monoamine neurotransmitters and analogues. Owing to the unique DNA like double-helicity structure of the homochiral ZMOF JLU-Liu23, the good enantioseparation of four monoamine neurotransmitters and analogues was achieved on the prepared homochiral ZMOF JLU-Liu23 coated capillary column. The relative standard deviations (RSDs) of the analytes migration time for intra-day, inter-day and column-to-column were in the range of 0.3-0.6%, 0.8-2.2% and 3.5-6.5%, respectively.

The popularity of novel nanoparticles coated capillary column has aroused widespread attention of researchers. Metal organic frameworks (MOFs) with special structure and chemical properties have received great interest in separation sciences. This work presents the investigation of HKUST-1 (Hong Kong University of Science and Technology-1, called Cu3(BTC)2 or MOF-199) nanoparticles as a new type of coating material for capillary electrochromatography. For the first time, three layers coating (3-LC), five layers coating (5-LC), ten layers coating (10-LC), fifteen layers coating (15-LC), twenty layers coating(20-LC) and twenty-five layers coating (25-LC) capillary columns coated with HKUST-1 nanoparticles were synthesized by covalent bond with in situ, layer-by-layer self-assembly approach. The results of scanning electron microscopy (SEM), X-ray diffraction (XRD) and plasma atomic emission spectrometry (ICP-AES) indicated that HKUST-1 was successfully grafted on the inner wall of the capillary. The separating performances of 3-LC, 5-LC, 10-LC, 15-LC, 20-LC and 25-LC open tubular (OT) capillary columns were studied with some neutral small organic molecules. The results indicated that the neutral small organic molecules were separated successfully with 10-LC, 15-LC and 20-LC OT capillary columns because of the size selectivity of lattice aperture and hydrophobicity of organic ligands. In addition, 10-LC and 15-LC OT capillary columns showed better performance for the separation of certain phenolic compounds. Furthermore, 10-LC, 15-LC and 20-LC OT capillary columns exhibited good intra-day repeatability with the relative standard deviations (RSDs; %) of migration time and peak areas lying in the range of 0.3-1.2% and 0.5-4.2%, respectively. For inter-day reproducibility, the RSDs of the three OT capillary columns were found to be lying in the range of 0.3-5.5% and 0.3-4.5% for migration time and peak area, respectively. The RSDs of retention times for column-to-column for three batches of 10-LC, 15-LC and 20-LC OT capillary columns were in the range from 2.3% to 7.2%. Moreover, the fabricated 10-LC, 15-LC and 20-LC OT capillary columns exhibited good repeatability and stability for separation, which could be used successively for more than 120 runs with no observable changes on the separation efficiency.

A family of nonlinear optical materials that contain the halide, oxide, and oxyhalide polar units simultaneously in a single structure, namely ABi

Because 2,4,6-trinitrophenol (TNP) and its analogues such as 2,4,6-trinitrotoluene (TNT) possess similar chemical structures and properties, the reliable and accurate detection of TNP from its analogues still remains a challenging task. In the present work, a selective and sensitive method based on the water-soluble silicon nanoparticles (SiNPs) for the determination of TNP was established. The SiNPs with good thermostability and excellent antiphotobleaching capability were prepared via a simple one-pot method. Compared with the synthesized time of other nanomaterials with respect to the detection of TNP, this method avoided a multistep and time-consuming synthesis procedure. Significantly, the fluorescence of the SiNPs could be remarkably quenched by TNP via an inner filter effect. A wide linear range was obtained from 0.02 to 120 μg/mL with a limit of detection of 6.7 ng/mL. The method displayed excellent selectivity toward TNP over other nitroaromatic explosives. The proposed fluorescent method was successfully applied to the analysis of TNP. Moreover, a straightforward and convenient fluorescent filter paper sensor was developed for the detection of TNP, providing a valuable platform for TNP sensing in public safety and security.

Inspired by the chiral recognition ability of β-cyclodextrin and the natural adhesive properties of polydopamine under alkaline conditions, in this study, a rapid and in situ modification strategy was developed to fabricate β-cyclodextrin/polydopamine composite material coated-capillary columns for open tubular capillary electrochromatography. The results of scanning electron microscopy, FTIR spectroscopy, streaming potential and electro-osmotic flow studies indicated that β-cyclodextrin/polydopamine was successfully fixed on the inner wall of the capillary column. This coating can be achieved within 1 h affording a greatly reduced capillary preparation time. The performance of the β-cyclodextrin/polydopamine-coated capillary was validated by the analysis of seven pairs of chiral analytes, namely epinephrine, norepinephrine, isoprenaline, terbutaline, verapamil, tryptophane, carvedilol. Good enantioseparation efficiencies were achieved for all. For three consecutive runs, the relative standard deviations for the migration times of the analytes for intra-day, inter-day and column-to-column repeatability were in the range of 0.41–1.74%, 1.03–4.18%, and 1.66–8.24%, respectively. Moreover, the separation efficiency of the β-cyclodextrin/polydopamine-coated capillary column did not decrease obviously over 90 runs. The strategy should also be feasible to introduce and immobilize other chiral selectors on the inner walls surface of capillary columns. This article is protected by copyright. All rights reserved

The latest developments in chiral analysis of β-blocker drugs by capillary electromigration techniques are reviewed in this article. Following the previous review by Aturki et al. [Electrophoresis 2011, 32, 2602-2628], this review includes the papers published during the period from January 2011 to December 2013. During this time, some novel chiral selectors were reported and applied to improve the enantioseparation of β-blocker drugs and structurally related compounds. These chiral selectors include CDs and their derivatives, macrocyclic antibiotics, tartrate complexs, the monolithic molecularly imprinted polymer, and the polymeric surfactants. In addition, this article summarizes the methodological improvements for enhancing sensitivity in chiral analysis of β-blockers and structurally related compounds by CE. The involved authors described the use of online sample preconcentration techniques to increase the detection sensitivity in the enantiomeric analysis of a broad range of samples.

In this work, core-satellites nanostructural composites have been synthesized through self-assembly combined with in situ growth strategy for catalytic degradation of common organic contaminants. At first, a three-component microsphere catalyst support containing alkyl-functionalized Fe3O4 magnetite core and a layered chitosan (CTS) shell has been constructed for loading of gold nanoparticles (Au NPs). Wherein, the Fe3O4 microsphere core is in favor for recycling and the formation of a hexadecyltrimethoxysilance@CTS (C-16@CTS) layer effectively increases its surface area and provides more docking sites for small Au satellite NPs to construct core-satellites nanostructure. Through electrostatic interaction and coordination, small Au NPs automatically assembled on the surface of support which served as seeds for further in situ growth of bigger stable Au NPs. The obtained catalyst was stable and had enhanced performance for fast catalytic reduction and fading of common organic contaminants, including 4-nitrophenol (4-NP), methylene blue (MB), Congo red (CR), rhodamine B (RhB), rhodamine 6G (R6G), acid orange (AO) and methyl orange (MO). No significant inactivation of the catalyst was observed even after recycling for eleven cycles or stored for more than 1 month. In addition, the catalyst was used for effective degradation of organic pollutant in Yellow River water sample, which indicated its potential for practical applications in water pollutant removal and environmental remediation. (C) 2014 Elsevier B.V. All rights reserved.

In this work, one pot strategy was proposed for in situ growth of Au nanoparticles (Au NPs) on the surface of amine-modified graphene oxide (GO@NH2) nanosheets. Au NPs were generated via an in situ reduction of Au3+ by Cu+ which was linked to the surface of GO@NH2 nanosheets through inorganic grafting. The initial Au NPs then served as seed for subsequent particle growth. The as-obtained GO@NH2-Au nanocomposites (GO@NH2-Au NCs) exhibited high catalytic activity for the degradation of 4-nitrophenol, which was a refractory pollutant that occur in industrial waste water. The catalytic efficiency was examined by turnover frequency (TOF). It was calculated to be 595 h(-1), which was higher than that of other Au catalysts. Furthermore, the as-prepared catalyst showed high cycle stabilization during the catalytic reduction. (C) 2014 Elsevier B.V. All rights reserved.

Two series of hyperbranched polymers based on alkyl-modified 2,4,6-tris(thiophen-2-yl)-1,3,5-triazine central units linked through fluorene bridges of different lengths have been synthesized via Suzuki coupling. The two series of polymers differ in the position of alkyl substitution within the thienyl group, which can be either closer to the triazine core (P0–P10) or to the fluorene bridge (P0′–P10′). Introduction of a hexyl group at one of the β-positions of the thienyl group improves the solubility of the polymers. A good control over the ratio of triazine and fluorene units allows for the systematic study of the polymer composition effects on the electrochemical, linear, and nonlinear photophysical properties. The nonlinear absorption has been shown to have a noticeable promotion with increasing molar ratio of the triazine core, while the emission quantum yield decreases. The position of alkyl substitution within the thienyl group has a significant effect on the two-photon absorption cross section. Sub...

This paper studies the problem of transfer learning in the context of reinforcement learning. We propose a novel transfer learning method that can speed up reinforcement learning with the aid of previously learnt tasks. Before performing extensive learning episodes, our method attempts to analyze the learning task via some exploration in the environment, and then attempts to reuse previous learning experience whenever it is possible and appropriate. In particular, our proposed method consists of four stages: 1) subgoal discovery, 2) option construction, 3) similarity searching, and 4) option reusing. Especially, in order to fulfill the task of identifying similar options, we propose a novel similarity measure between options, which is built upon the intuition that similar options have similar state-action probabilities. We examine our algorithm using extensive experiments, comparing it with existing methods. The results show that our method outperforms conventional non-transfer reinforcement learning algorithms, as well as existing transfer learning methods, by a wide margin.

In this paper, we first discovered that Co3O4 nanoparticles (NPs) possess intrinsic oxidase-like activity and can catalytically oxidize peroxidase substrates, such as 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and 3,3',5,5'-tetramethylbenzidine (TMB), to form colored products, in the absence of exogenously added H2O2. The presence of sulfite inhibited the TMB-O2-Co3O4 NPs reaction system and caused a change in color of the reaction system. On the basis of this phenomenon, a colormetric approach to detect sulfite was established with a good linear relationship ranging from 0.2×10(-6) to 1.6×10(-5) M and a detection limit of 5.3×10(-8) M. The method was used to detect sulfite in foods. Good recoveries ranging from 93.8% to 100.5% were obtained. Furthermore, the mechanism was studied and results showed that the oxidase-like activity of the Co3O4 NPs was not from •OH or O2•- radical generated. It may probably originate from their ability to transfer an electron between the peroxidase substrate and oxygen absorbed on the surface of the Co3O4 NPs.

A novel strong electron-acceptor, thieno[2,3-f]-2,1,3-benzothiadiazole-6-carboxylate (BTT), was first designed and synthesized. By introducing two thienyl groups into BTT and then copolymerizing with thienyl group substituted benzo[1,2-b:4,5-b′]dithiophene (BDTT) unit, a low band gap D–A copolymer (PBTT-TBDTT) was obtained. Compared with its polymer analogue (PBT-TBDTT) with benzothiadiazole (BT) as an acceptor, PBTT-TBDTT exhibits stronger intramolecular charge transfer. Thus, it shows much broader absorption covering almost the whole visible light region (in the range of 300–850 nm) and narrower optical band gap around 1.45 eV with a large IP (ionization potential) at 5.35 eV. The maximum efficiency of PBTT-TBDTT based device reaches 6.07% which is much higher than that of PBT-TBDTT (3.24%), indicating that BTT unit is a promising electron-acceptor moiety to construct low band gap D–A copolymers for PSCs with high photovoltaic performances.

This paper describes a colorimetric approach to determine trace amounts of nitrite in water supplies, meat and dairy products using 1-butyl-3-methylimidazolium-modified methyl red ([BMIM]MR) as a colour reagent. The technique capitalises on the catalytic effect of nitrite on the oxidative degradation of [BMIM]MR by potassium bromate in acidic media. The absorbances were proportional to nitrite concentrations in the range of 8.70 × 10−2 to 4.17 μM with a detection limit of 1.64 × 10−2 μM. Compared with the method using methyl red as a colour reagent, 60 times improvement of sensitivity was obtained. Activation energy and the apparent rate constant for the catalytic reaction are 61.11 kJ mol−1 and 1.18 × 104 s−1, respectively. The proposed method was successfully applied for the analysis of nitrite in Yellow River water, chicken, and milk with recoveries ranging from 96% to 105%.

In this study, cobalt doped magnetic composite nanoparticles (Co x Fe 3− x O 4 MNPs) were firstly prepared through a simple and convenient coprecipitation approach. The characterization results from EDX, ICP-AES, TEM, XRD and XPS showed that the cobalt atoms might be located in the lattice position instead of the part of iron atoms. Co x Fe 3− x O 4 MNPs possessed higher peroxidase-like activity comparing with Fe 3 O 4 MNPs, although they were similar in crystal structure, size distribution and morphology. The as-prepared nanomaterials could effectively catalyze the reaction between 3,3,5,5-tetramethylbenzidine (TMB) and H 2 O 2 under 40 °C within 15 min. Dopamine (DA) has some reducibility due to the existence of phenol hydroxyl group, which results in it can consume H 2 O 2 and cause the blue shallowing of the reaction solution between H 2 O 2 and TMB. A visual, sensitive and simple colorimetric method based on Co x Fe 3− x O 4 MNPs as peroxidase mimetics was developed for detecting DA. Good linear relationship and recoveries for DA were obtained from 0.6 to 8.0 μM and 98.7 to 101.0%, respectively. The limit of detection (LOD) of the proposed method was calculated as 0.13 μM. And the relative standard deviation (RSD) was less than 4.0%. The visual method was successfully applied to DA detection in Common Yam Rhizome (Shan Yao) and human serum sample.