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Present work depicted a novel electrochemical sensor fabricated with magnetic carbon dots (M-CDs) and cetyltrimethylammonium bromide (CTAB) modified glassy carbon electrode (GCE) for selective measurement of 3,3′,5,5′-tetrabromobisphenol A (TBBPA) in beverages. The M-CDs composite material revealed good electrocatalytic activity, and CTAB has strong hydrophobic interaction which enable it have good enrichment capacity of hydrophobic compounds, and combination of them further enhances the electrochemical signal. Hence CTAB decoration can markedly improve the detection performance of TBBPA. Electrochemical properties of the fabricated sensor was investigated through performing cyclic voltammetry (CV). The morphology and functional groups of the modified materials were examined with transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR). The results indicated that the synthesized material had a spherical-like structure, good dispersion properties and plenty of functional groups on the surface. The effects of incubation potential, incubation time, pH of electrolyte, and scanning rate on oxidation peak current were investigated. Under optimal conditions, the designed sensor had good linear range of 1 nM–1000 nM, and the detection of limit of the constructed sensor was 0.75 nM. The constructed sensor was utilized to detect TBBPA in vitamin water, scream drink and genki forest, and satisfactory detection performance had been achieved. • Magnetic carbon dots (M-CDs) were facile prepared with simple method. • M-CDs composite material revealed good electrocatalytic activity. • Novel electrochemical sensor was developed with M-CDs and CTAB. • Developed sensor provided good sensitivity of 0.75 nM for tetrabromobisphenol A. [ABSTRACT FROM AUTHOR]

Background: Pediatric obstructive sleep apnea/hypopnea syndrome (OSAHS) is a multifactorial syndrome caused by many risk factors, such as craniofacial anomalies, adenotonsillar hypertrophy, obesity, and airway inflammation. Although new treatment patterns have recently been proposed, treatment methods for children remain particularly challenging and controversial. This randomized controlled trial was designed to investigate the efficacy of adenotonsillectomy and/or orthodontic treatment for children who have mild OSAHS with mandibular retrognathia.Methods: A sample of 352 children with mild OSAHS and mandibular retrognathia, who are aged between 7 and 10 years, will be enrolled in the study. They will be randomized into four groups: the drug treatment group, the surgical treatment group, the orthodontic treatment group, or the surgery and postoperative orthodontic group. After randomization the children will receive treatments within 4 weeks. Outcome assessment will take place at the following points: (1) baseline, (2) 7 months after the treatment starting point, (3) 12 months after the treatment starting point, and (4) 24 months after the treatment starting point. The primary endpoint of the trial is the mean change in obstructive apnea/hypopnea index. Other endpoints will consist of the lowest oxygen saturation, apnea index, and hypopnea index assessed by polysomnography, subjective symptoms (assessed by the OSA-20 questionnaire), cephalometric measurements, and morphologic analysis of the upper airway.Discussion: The results of this study will provide valuable evidence for the merits and long-term efficacy of different treatment approaches and contribute to facilitating the multidisciplinary treatment of pediatric OSAHS.Trial Registration: ClinicalTrials.gov : NCT03451318. Registered on 2 March 2018 (last update posted 19 April 2018). [ABSTRACT FROM AUTHOR]

In forensic investigations, age estimation is vital for determining whether a suspect is under or over the legally defined adult age. With breakthroughs in RNA sequencing technology, small noncoding RNAs have provided new ways to solve problems related to the age estimation of trace or aged samples, owing to their small molecular weight and better stability. In our previous study, we had applied miRNAs for the age estimation of bloodstains; however, further improvement of the existing model is needed. PIWI-interacting RNAs (PiRNAs), which are 24–32 nt noncoding small RNA molecules involved in the PIWI-piRNA pathway, play an important role in the aging process. In this study, we explored the possibility of simultaneously analyzing piRNAs and miRNAs for better age estimation purpose. Through massively parallel sequencing, five age-related piRNAs were identified in blood samples that had been stored for eight years. Further real-time PCR analysis revealed that two piRNAs (piR-000753 and piR-020548) showed relatively higher efficiency in age estimation. Additionally, two age-related miRNAs (miR-324-3p and miR-330-5p) were used to build the estimation model. Among all algorithms tested, gradient boosting showed the lowest mean absolute error (MAE) and root mean square error (RMSE) values (3.171 and 4.403 years, respectively) for the validation dataset (n = 110). The errors of the model were less than 5 years and 10 years for 81.82% and 96.36% of the samples, respectively. The results suggest that the combined use of piRNA and miRNA markers may increase the accuracy of age estimation, and our new model has great potential for application in forensic casework. [ABSTRACT FROM AUTHOR]

In this work, fabrication of Cu2O@Cu1.75S core‐shell octahedrons was achieved through a facile water bath stirring process. Compared with pure Cu2O, the composite showed enhanced sensing performance for NO2. The response value of Cu2O@Cu1.75S to 5 ppm NO2 at 40 °C is seven times that of Cu2O to 5 ppm NO2 at 75 °C. Moreover, Cu2O@Cu1.75S has the ability to detect 100 ppb NO2 and has good NO2 sensing selectivity and long‐term stability. This study shows that Cu2O@Cu1.75S hybrid is a type of outstanding NO2 gas sensing material on account of its low working temperature and high sensing sensitivity. [ABSTRACT FROM AUTHOR]

In order to effectively compensate negative sequence current (NSC) of the V/v traction system and reduce the capacity and cost of railway power conditioner (RPC), a low-cost hybrid railway power conditioner (HRPC) technology scheme considering regenerative braking energy is proposed in this paper. The proposed HRPC consists of an RPC with a modular multilevel converter structure (MMC-RPC) and a railway static var compensator (RSVC). First, the circuit topology of the proposed scheme and the principle of NSC compensation considering regenerative braking energy are given. Then, the capacity configurations of MMC-RPC and RSVC are presented to reduce the capacity of active equipment and further lower the investment cost of HRPC. On this basis, the HRPC with energy storage units (ESU-HRPC) is studied to recycle the remaining regenerative braking energy, and the difference from the proposed HRPC is further analyzed. Subsequently, the capacities of HRPC and ESU-HRPC are designed based on the measured power data from a heavy-haul railway in China as an example. Besides, the system control strategy is given. Finally, the proposed technical schemes are verified by the hardware in loop (HIL) experiments. [ABSTRACT FROM AUTHOR]

Genetic modification of industrial yeast strains often faces more difficulties than that of laboratory strains. Thus, new approaches are still required. In this research, the Angel Yeast‐derived haploid strain Kα was genetically modified by multiple rounds of δ‐integration, which was achieved via URA3 recycling. Three δ‐integrative plasmids, pGδRU, pGδRU‐BGL, and pGδRU‐EG, were first constructed with two 167 bp δ sequences and a repeat‐URA3‐repeat fragment. Then, the δ‐integrative strains containing the bgl1 or egl2 gene were successfully obtained by one‐time transformation of the linearized pGδRU‐BGL or pGδRU‐EG fragment, respectively. Their counterparts in which the URA3 gene was looped out were also easily isolated by selection for growth on 5´‐fluoroorotic acid plates, although the ratio of colonies lacking URA3 to the total number of colonies decreased with increasing copy number of the corresponding integrated cellulase‐encoding gene. Similar results were observed during the second round of δ‐integration, in which the δ‐integration strain Kα(δ::bgl1‐repeat) obtained from the first round was transformed with a linearized pGδRU‐EG fragment. After 10 rounds of cell growth and transfer to fresh medium, the doubling times and enzyme activities of Kα(δ::bgl1‐repeat), Kα(δ::egl2‐repeat), and Kα(δ::bgl1‐repeat)(δ::egl2‐repeat) showed no significant change and were stable. Further, their maximum ethanol concentrations during simultaneous saccharification and fermentation of pretreated corncob over a 7‐day period were 46.35, 33.13, and 51.77 g/L, respectively, which were all substantially higher than the parent Kα strain. Thus, repetitive δ‐integration with URA3 recycling can be a feasible and valuable method for genetic engineering of Angel Yeast. These results also provide clues about some important issues related to δ‐integration, such as the structural stability of δ‐integrated genes and the effects of individual integration‐site locations on gene expression. Further be elucidation of these issues should help to fully realize the potential of δ‐integration‐based methods in industrial yeast breeding. [ABSTRACT FROM AUTHOR]

Sewage and sludge are usually treated separately. Considering improving sludge treatment while improving sewage treatment is beneficial to the synergetic effect of sewage treatment and sludge treatment. The efficiency of pulverized coal‐activated sludge (PAS) on contaminant removal, sludge calorific value, and combustion characteristic was investigated in contrast to conventional activated sludge (CAS) using the laboratory‐scale sequencing batch reactor (SBR). Results indicated that the average chemical oxygen demand, ammonium nitrogen, total nitrogen, and total phosphorus removal efficiency of PAS were highest under a dosage of 0.4 g/L, which were 98.56%, 94.22%, 68.60%, and 95.96%, respectively. The average effluent concentration satisfied the Level A discharge standard of pollutants for municipal wastewater treatment plants (GB18918‐2002). The calorific value and maximum weight loss of PAS gradually increased adjusting the dosage of pulverized coal. At the pulverized coal dosage of 0.2 g/L, the calorific value of PAS with 70% water content is 3,824.07 kJ/kg, which can satisfy the requirement of self‐maintained combustion. Overall, the pulverized coal can simultaneously improve the treatment of wastewater in SBR and promote the sludge combustion by increasing calorific value. Therefore, PAS system is an innovation based on improving the sewage treatment sludge combustion. Practitioner points: An innovative method to simultaneously improving wastewater treatment and sewage sludge combustion using pulverized coal‐activated sludge was developed.The average COD, NH4+‐N, TN, and TP removal efficiency of PAS‐0.4 is best.The 70% moisture content sludge calorific values of 3,824.07 kJ/kg in PAS‐0.2 can satisfy the requirement of self‐maintained combustion. [ABSTRACT FROM AUTHOR]

Organochlorine pesticides (OCPs) have received much attention due to their toxicity. Reliable methods to monitor their residues in the environment are needed. Here, magnetic polyamidoamine dendrimers were prepared by co-precipitation, Michael addition, and amidation. The magnetic polyamidoamine dendrimers demonstrated good adsorption ability for OCPs—this feature was utilized to construct a sensitive tool for monitoring OCPs in water samples. The proposed method provided remarkable linearity from 0.1 to 500 μg/L and satisfactory limits of detection from 0.012 to 0.029 μg/L. The spiked recoveries of the four target analytes were 91.8%−103.5% with relative standard deviations less than 4.5%. The magnetic materials had good reusability. The results indicated that the resulting method was an efficient, easy, rapid, economical, and eco-friendly tool for monitoring OCPs in aqueous samples. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• ASC chemiluminescence immunoassay we developed showed a good analytical performance. • Studies have shown that serum ASC might be a promising indicator for the diagnosis of stroke especially in the hyperacute phase. • Serum ASC concentration closely correlated with severity of stroke. Apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) is a promising stroke biomarker. However, a large study of human serum ASC has not yet to be reported; additionally, the diagnostic value of prehospital concentration and practicality of ASC remains unknown. We recruited 774 Chinese stroke patients, including 523 with ischemic stroke (IS) and 251 with hemorrhagic stroke (HS) within 14 days following symptom onset in the emergency department, alongside 481 healthy individuals and 64 cognitive impairment patients as controls. Serum ASC concentrations were determined using automated chemiluminescence immunoassay, exploring the relationship between serum ASC concentration and subtypes, severity, and sampling timepoints of stroke. ASC concentrations were significantly higher in stroke patients compared with all controls (P < 0.001). HS patients had greater ASC concentrations than IS patients (P < 0.05). With increasing ASC concentration, the proportion of severe cases increased. The area under the receiver operating characteristic curve (AUC) for differentiating between healthy individuals and stroke patients in the hyperacute phase was 0.78; this markedly improved (0.90) when considering samples from healthy individuals and patients with subarachnoid hemorrhage (SAH) ≤ 3 h from last-known-well (LKW). Serum ASC is a valuable biomarker for stroke differentiation and aids in the clinical diagnosis of stroke severity and subtypes. [ABSTRACT FROM AUTHOR]

• MNP@PAMAM-Gn@C 60 were firstly synthesized by simple method. • Modification with PAMAM and C 60 endow target magnetic material excellent adsorption. • MNP@PAMAM-Gn@C 60 based MSPE provided high enrichment and sensitivity for PCBs. • The proposed method was reliable and effective for measurement of PCBs in beverages. Polychlorinated biphenyls (PCBs) are persistent organic pollutants which are widely present in environment and harmful to human health. In this study, an efficient and convenient magnetic solid phase extraction method with C 60 modified magnetic polyamido-amine (PAMAM) dendrimers as sorbents was established for enriching trace amounts of PCBs in beverage samples. Gas chromatography-tandem mass spectrometry (GC–MS/MS) was utilized for analysis of PCBs. Parameters affecting extraction efficiency were optimized. Under optimal parameters, good linearity can be achieved in concentration range of 0.001–20 μg L−1 and 0.002–20 μg L−1 for nine selected PCBs. The limits of detection for PCBs were in the range of 0.1–0.2 ng L-1. The spiked recoveries were in the range of 87.0 %–115.1 % (n = 3). The results proved that this established method was reliable for monitoring trace PCBs in beverage samples. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are a kind of hazardous persistent organic contaminants and widely present in nature due to large consumption in the past. Although PCBs have been banned in many countries of the world, they are still present at trace level in food and water samples. It is of significant value to establish reliable enrichment and detection method. Based on the conversion of the hydrophilicity and hydrophobicity from heptanoic acid under alkali and acid, increasing the contact area between heptanoic acid and PCBs, a new switchable solvent micro-extraction method for PCBs from beverages was developed with good extraction efficiency using heptanoic acid as the extractant prior to gas chromatography-tandem mass spectrometry (GC-MS/MS). The key parameters that had impact on enrichment of PCBs were investigated in detail. Under the optimal conditions, a good linearity can be achieved in a concentration range of 0.01–20 μg L−1 with the correlation coefficients of 0.9978–0.9994. Limits of detection for PCB28, PCB53, PCB206 were 3 ng L−1 and PCB118 was 5 ng L−1 while other target PCBs were 2 ng L−1. Intra-day and inter-day precisions were in the range of 1.9–4.2% and 2.1–4.2％(relative standard deviation, RSD, n = 6), respectively. The real sample spiked recoveries of the targets were in the range of 93.2–114.3％ (n = 3). The enrichment factors were in the range of 16.2–17.9. The results proved that this method was reliable for monitoring trace PCBs in beverage samples and will help for future assessments of impacts on human and animal health. • A switchable solvent microextraction method was established for enrichment of PCBs. • Enrichment is due to conversion between hydrophobic and hydrophilic forms of heptanoic acid. • The method was reliable, sensitive, simple and effective for measurement of PCBs. [ABSTRACT FROM AUTHOR]

In this study, graphene oxide modified magnetic polyamidoamine dendrimers (MNPs@PAMAM-G2.0@GO) nanoparticles were successfully prepared by amidation method. The obtained MNPs@PAMAM-G2.0@GO nanocomposites were examined by fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscope (SEM) and transmission electron microscopy (TEM), etc. MNPs@PAMAM-G2.0@GO exhibited excellent adsorption property and was investigated for magnetic solid phase extraction (MSPE) of polycyclic aromatic hydrocarbons (PAHs) from water. The detection of extracted PAHs was accomplished by high performance liquid chromatography (HPLC) and gas chromatography tandem mass spectrometry (GC-MS/MS). The target PAHs included anthracene (ANT), pyrene (PYR), fluoranthene (FLT), carbazole (CB), 7-methylquinoline (7-MQL), 9-methylcarbazole (9-MCB), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DBT). Important operation parameters for MSPE that could affect the extraction efficiencies of PAHs were investigated in detail. Under optimal parameters, the constructed method demonstrated excellent linear range with 0.001–10 μg L−1 for analytes and low limits of detection within the range of 0.11–0.9 ng L−1. The spiked average recoveries of PAHs in natural water samples ranged from 92.5% to 105.2%. The promising results indicated that MNPs@PAMAM-G2.0@GO could be employed to efficiently extract PAHs from aqueous samples. [Display omitted] • Magnetic dendrimers modified with graphene oxide exhibited good adsorption for PAHs. • An efficient magnetic solid phase extraction method was developed for PAHs. • The method provided advances of rapidity, sensitivity, easy operation and low cost. [ABSTRACT FROM AUTHOR]

The global effort against the COVID-19 pandemic dictates that routine quantitative detection of SARS-CoV-2 neutralizing antibodies is vital for assessing immunity following periodic revaccination against new viral variants. Here, we report a dual-detection fluorescent immunochromatographic assay (DFIA), with a built-in self-calibration process, that enables rapid quantitative detection of neutralizing antibodies that block binding between the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein and the angiotensin-converting enzyme 2 (ACE2). Thus, this assay is based on the inhibition of binding between ACE2 and the RBD of the SARS-CoV-2 spike protein by neutralizing antibodies, and the affinity of anti-human immunoglobulins for these neutralizing antibodies. Our self-calibrating DFIA shows improved precision and sensitivity with a wider dynamic linear range, due to the incorporation of a ratiometric algorithm of two-reverse linkage signals responding to an analyte. This was evident by the fact that no positive results (0/14) were observed in verified negative samples, while 22 positives were detected in 23 samples from verified convalescent plasma. A comparative analysis of the ability to detect neutralizing antibodies in 266 clinical serum samples including those from vaccine recipients, indicated that the overall percent agreement between DFIA and the commercial ELISA kit was 90.98%. Thus, the proposed DFIA provides a more reliable and accurate rapid test for detecting SARS-CoV-2 infections and vaccinations in the community. Therefore, the DFIA based strategy for detecting biomarkers, which uses a ratiometric algorithm based on affinity and inhibition reactions, may be applied to improve the performance of immunochromatographic assays. • A dual-detection fluorescent immunochromatographic assay (DFIA) was developed. • DFIA is a ratiometric detection method based on inhibition of ACE2 & RBD binding. • DFIA is self-calibrating & shows improved precision and sensitivity. • DFIA enables rapid quantitative detection of neutralizing antibodies. • Overall percent agreement between DFIA and the commercial ELISA kit was 90.98%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen-doped carbon dots were fabricated by a simple hydrothermal strategy. • N-CDs exhibited strong fluorescence property, stability and water solubility. • The sensor was endowed high sensitivity and selectivity for Cu2+ detection. • The sensor can be applied in weak acid and high salt environment. A new kind of nitrogen-doped carbon dots (N-CDs) was synthesized via a simple hydrothermal strategy using humic acid as the carbon source and urea as the nitrogen source. The fluorescence intensity of as-prepared N-CDs was quenched significantly in presence of Cu2+ based on a specific inner filter effect, which could be utilized to construct a selective sensor for monitoring Cu2+ in aqueous samples. The sensor exhibited good linearity over the range of 0.1–2 μM, and high sensitivity with a detection limit of 25 nM. Under the optimal conditions, there was no significant interference by other metal ions such as Cd2+, Al3+, Cr3+, Fe3+, Pb2+, Na+, Ni+, Fe2+, Ba2+, Ca2+, Co2+, Mg2+, As3+, K+, Zn2+ for Cu2+ detecting except Hg2+. The interference of Hg2+ can be masked by addition of sodium chloride. The experimental results demonstrated that the prepared N-CDs owned strong fluorescence, high monodispersity, good stability and good water solubility, and the constructed sensor had many advances and great application prospect in environmental field. [ABSTRACT FROM AUTHOR]

4-Carboxyphenylboronic acid was used as the single precursor to facilely prepare fluorescent carbon quantum dots by one-step solvothermal method. The as-obtained carbon dots (CDs) exhibited highly selective and sensitive for benzo[a]pyrene (BaP), and may be a splendid sensor for sensing BaP. The principle was that the as-prepared CDs could form a complex with BaP through hydrophobic interaction which causes the decrease of fluorescence intensity of CDs by static quenching principle. The constructed fluorescent sensor exhibited excellent linearity ranged from 0.002 to 0.06 μg mL−1 and provided a low limit of detection of 0.16 ng mL−1. The experimental results showed that this fluorescent sensor resulted in simplicity, rapidness, low cost, short analytical time, and high sensitivity and stability. Validation with real water samples endowed the sensor high reliability and feasibility for BaP determination in practical application in various samples. • Selective carbon dots are facilely derived from 4-carboxyphenylboronic acid. • Carbon dots exhibit good selective and sensitive for BaP. • Fluorescence detection of BaP is based on static quenching mechanism. • The sensor shows high feasibility and provides good sensitivity of 0.16 ng mL−1. [ABSTRACT FROM AUTHOR]

In present work, we reported a new nanomaterial nano Fe0 decorated with SiO 2 and dopamine by self-assembly method (Fe@SiO 2 @PDA). A sensitive method for determination of Sudan pollutants in aqueous samples was developed using Fe@SiO 2 @PDA as magnetic solid phase extraction adsorbents prior to high-performance liquid chromatography with variable wavelength detector. The possible parameters which would affect the enrichment have been optimized. The best parameters were as follows: elutent, 4.5 mL methanol; adsorbent dosage, 30 mg; adsorption time, 20 min; elution time, 18 min; sample pH 7; sample volume, 40 mL. The experimental results demonstrated that Fe@SiO 2 @PDA exhibited good adsorption properties to Sudan Red dyes. The established method provided excellent linear ranges over 0.01–50 μg L−1 and detection limits ranged from 2.0 to 5.1 ng L−1 for Sudan red I-IV. The developed method was also evaluated with real water samples and the results demonstrated that it was of applicative value owing to its merits including robustness, easy operation, fastness, cheapness and high enrichment efficiency, and had great prospect in environmental fields. • Fe@polydopamine was easily prepared and earned excellent enrichment capability. • Modification with dopamine endowed nanoscale zero valent iron with new applications. • Established method provided good sensitivity from 2 to 5.1 ngL−1 for Sudan I-IV. • The developed method earned merits of various merits and great prospect. [ABSTRACT FROM AUTHOR]

Carbon dots have been a promising nano-carbon material with many advantages, and attracted many more attentions. This study designed a new chemosensor integrating the strong fluorescent property of carbon dots and the magnetism of amino-functionalized magnetic core-shell nanomaterial, Fe@SiO 2 –NH 2 for determination of 2,4,6-trinitrotoluene (TNT). In this system, fluorescent carbon dots interacted with amino groups on the surface of amino-functionalized magnetic core-shell nanomaterial leading to fluorescence quenching of carbon dots, appearance of TNT competitively replaced of carbon dots on the surface of the magnetic material through forming a Meisenheimer complex. This sensor exhibits excellent selectivity and sensitivity for TNT, and which provided a good dynamic linear range for TNT from 10 to 2000 ng mL−1. The experiments demonstrate a low detection limit of 2.15 ng mL−1. The intra-day precisions for 25, 100 and 500 ng mL−1 were 4.6, 2.3 and 0.5% (RSD, n = 6), inter-day precisions for 25, 100 and 500 ng mL−1 were 4.2, 2.5 and 0.9% (RSD, n = 6), respectively. The developed sensor was validated with river water, dust, and soil samples, and the achieved spiked recoveries were immensely satisfied from 98.1% to 102.0%. The Fe@SiO 2 –NH 2 possessed excellent reusability. This sensor exhibits that it is simple, sensitive and selective, and will be a vital analytical tool for TNT in many fields. [Display omitted] • Carbon dots were facilely synthesized with sodium citrate and polyacrylamide. • Sensitive chemosensor was developed with Fe@SiO 2 –NH 2 and the prepared carbon dots. • Chemosensor exhibits good sensitivity and selectivity for TNT. • The sensor provided remarkable merits and had promising application prospect. [ABSTRACT FROM AUTHOR]

Polyamidoamine dendrimer decorated Fe 3 O 4 magnetic nanoparticles was synthesized and grafted with 4-mercaptobenzoic acid (4-MBA). The resulting material was utilized to develop an effective magnetic solid phase extraction method in combination with high performance liquid chromatography for trace determination of polycyclic aromatic hydrocarbons including phenanthrene (PHE), anthracene (ANT), fluoranthene (FLT), pyrene (PYR) and benzo(a)pyrene (BaP). The MNPs@G3.0@4-MBA exhibited to be an efficient extracting medium due to the existence of terminal benzene ring groups, the internal pores, and strong hydrophobic interactions and π-π interactions. The experiments demonstrated that the proposed method possessed excellent linearity in the concentration range of 0.1–300 μg L−1 with correlation coefficients (R) larger than 0.997, and the limits of detection (LODs, S/N = 3) according to the ratio of signal to noise equal to three of PHE, ANT, FLT, PYR and BaP were 0.014 μg L−1, 0.032 μg L−1, 0.055 μg L−1, 0.027 μg L−1 and 0.039 μg L−1, respectively. The proposed method was applied to real water samples and the spiked recoveries were over the range of 92–99%. The results showed that the method earned good repeatability and high sensitivity, and the as-prepared materials were stable and reusable, which displayed that the proposed method would have a wonderful application prospect. Image 1 • 4-Mercaptobenzoic acid grafted PAMAM dendrimer decorated Fe 3 O 4 was prepared. • MNP@G3.0@4-MBA exhibited excellent adsorption capacity for PAHs. • The method provided good sensitivity with low LODs of 0.014–0.055 μgL−1 for PAHs. • The method was robust, simple and of low cost and good repeatability. [ABSTRACT FROM AUTHOR]

An ordered g–C 3 N 4 – and polyaniline-modified titanium oxide nanotube array (g–C 3 N 4 – and PANI-co-modified TiO 2 NTAs) was successfully synthesized and used as a photocatalyst. Polyaniline (PANI) was coated onto TiO 2 NTAs by electrochemical polycondensation, and g-C 3 N 4 was deposited via the soaking adsorption method. The photocatalysts were examined by several technologies. The experiments demonstrated that the amount of g-C 3 N 4 and PANI, as well as the initial pH value, had significant effects on the photocatalytic efficiency. The resulting photocatalysts exhibited high visible light photocatalytic ability for tetrabromobisphenol A (TBBPA) for two reasons. First, PANI expanded the light absorption into the visible region. Second, rapid and efficient separation of photoinduced charges from the photogenerated potential difference were produced at the contact interface of g-C 3 N 4 and PANI-co-modified TiO 2 NTAs. The •OH, • O 2 − and h+ were dominant components for the photocatalytic degradation of TBBPA. In addition, the g-C 3 N 4 and PANI-co-modified TiO 2 NTAs have excellent long-term stability. • g–C 3 N 4 – and PANI-co-modified TiO 2 NTAs was synthesized by a facile method. • g–C 3 N 4 – and PANI-co-modified TiO 2 NTAs markedly enhanced photocatalytic activity. • g-C 3 N 4 and PANI co-modification generated strongly synergistic effect. [ABSTRACT FROM AUTHOR]

2,4,6-Trinitrophenol (TNP) has absorbed much concerns because of its toxic effect and threat on the environment, which results from the fact that it is an important and universal reagent widely utilized for manufacturing many products. It is of great necessity to explore facile and efficient methods for monitoring TNP. In present study, carbon dots (CDs), a new carbonaceous nanomaterial with strong fluorescence, was applied to build a novel sensor for highly sensitive and selective detection of TNP. In the sensing procedure, the fluorescence intensity of as-prepared CDs was diminished with the presence of TNP due to inner filter effect (IFE) quenching mechanism. The sensitivity of the fluorescent sensor was very high with limit of detection down to 5.37 ng mL−1. This fluorescent sensor was evaluated and excellent spiked recoveries were gained, which demonstrated that the developed sensor would be a robust tool for environmental applications. Unlabelled Image • Fluorescent CDs were prepared by a facile and reliable method. • Sensitive sensor was developed with carbon dots based on inner filter effect. • This sensor earned high sensitivity with LOD of 5.37 ng mL−1. [ABSTRACT FROM AUTHOR]