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The study of atomically dispersed metal‐nitrogen electrocatalysts is still limited in terms of understanding their catalytic mechanism because of the inability to precisely regulate the coordination number and type of N in combination with the metal elements. Inspired by the high catalytic activity and selectivity of natural enzymes, herein, we have designed and fabricated ultrathin carbon nanosheet‐supported Mn single‐atom catalysts (SACs) with a precise pyrrole‐type Mn‐N4 (PT‐MnN4) configuration using a bio‐mimicking strategy. The PT‐MnN4 SACs display outstanding oxygen reduction reaction (ORR) activity, with a half‐wave potential (E1/2) of 0.88 V (vs. revisible hydrogen electrode [RHE]) and extremely high stability in alkaline media. Moreover, superior ORR activities are also obtained, E1/2 of 0.73 V and 0.63 V in acid and neutral electrolytes, respectively, indicating the efficient pH‐universal ORR performances. The assembled zinc–air battery using the PT‐MnN4 SACs as air cathodes exhibits a high peak power density (175 mW cm−2) and long‐term stability up to 150 h, implying its promising application in metal–air batteries. This study has paved the way toward the rational design and precise regulation of single‐atom electrocatalysts.

Stable and recyclable catalysts are crucial to the peroxymonosulfate (PMS) based advanced oxidation process (AOPs) for wastewater treatment. Herein, nitrogen-rich carbon wrapped Fe3C (Fe3C@CN) on carbon felt (CF) substrate was synthesized by using Prussian blue (PB) loaded CF as the precursors. The obtained Fe3C@CN/CF catalyst was applied for degradation of bisphenol A (BPA) via the heterogeneous catalytic activation of PMS. Results showed that ~91.7%, 95.2%, 98.1% and 99.1% of BPA (20 mg/L) were eliminated in the Fe3C@CN/CF + PMS system within 4, 10, 20 and 30 min, respectively. The fast degradation kinetics is attributed to the production of abundant reactive species ( OH, SO4 − and 1O2) in the Fe3C@CN/CF + PMS system, as demonstrated by the electron paramagnetic resonance spectroscopy and quench experiments. The Fe3C@CN/CF catalyst was stable and can be easily recycled by using an external magnet. The results indicated that the nanoconfined Fe3C endowed Fe3C@CN/CF with high stability and magnetic property and enabled the efficient electron transfer for PMS activation. This study provides a cost-effective approach for the fabrication of stable and recyclable Fe3C@CN/CF catalyst, and shed a new light on the rational design of multifunctional catalyst for advanced water remediation.

Graphitic carbon nitride (g-C3N4), with a moderate band gap (∼2.7 eV), high chemical and thermal stability, has been the hotspot in environmental photocatalysis. However, its performance is still u...

Partial denitrification combined with Anammox is a promising approach for simultaneous removal of ammonium and nitrate from wastewaters. In this study, the start-up, influencing factors and stable operation of partial denitrification for treating biological effluent from landfill leachate were investigated. High nitrate loads (3.85 kg N m−3 d−1) and short hydraulic retention time (0.66 h) were obtained in the partial denitrification process, yielding a suitable ratio of NO2−-N/NH4+-N in the effluent for downstream Anammox process. The study also revealed the importance of carbon sources, COD/NO3−-N ratio and salinity in the partial denitrification. Acetate-type carbon source, COD/NO3−-N ratio of about 3.0 and salinity lower than 1% favored high-efficient partial denitrification. The endogenous carbon sources from high-rate partial denitrification sludge contributed to low COD consumption in the process. During the partial denitrification, the dominant genus of Thauera was enriched, and shifted to Pseudomonas with the increase of organic removal rates.

Resuscitated strains which were obtained by addition of resuscitation promoting factor (Rpf) could provide a vast majority of microbial source for obtaining highly efficient polychlorinated biphenyl (PCB)-degrading bacteria. In this study, the Castellaniella sp. strain SPC4 which was resuscitated by Rpf addition showed the highest efficiency in degradation of 3,3′,4,4′-tetrachlorobiphenyl (PCB 77) among the resuscitated and non-resuscitated isolates. Further investigations on the PCB 77 degradation capability of the resuscitated strain SPC4 showed that SPC4 could efficiently degrade PCB 77 with maximum degradation rate (qmax) of 0.066/h at about 20 mg/L of PCB 77. The maximum growth rate on PCB 77 was 2.663 × 107 CFU/(mL·h) (0.024/h). The most suitable model of Edward demonstrated that the SPC4 could achieve qmax of 0.9315/h, with substrate-affinity of 11.33 mg/L and substrate-inhibition constants of 11.41 mg/L. Meanwhile, the presence of bphA gene expression and chlorine ions release, together with the identification of metabolites, confirmed that the bph-encoded biphenyl pathway was involved in PCB 77 mineralization by SPC4. This report is the first to demonstrate aerobic degradation of PCB 77 by the resuscitated strain Castellaniella sp. SPC4, indicating excellent potential for PCB bioremediation.

The goal of this work was to investigate the genetics of an acidophilic phenol-degrading yeast strain using whole-genome sequencing (WGS), characterize the growth of the strain and phenol degradation capability as well as degradation pathway under extremely acidic conditions. The result showed that the strain ZM1 isolated from an acid mine drainage (AMD) belongs to basidiomycetous yeast Rhodotorula sp., which possesses some unique genes compared to other four closely related Rhodotorula species. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis suggested that ZM1 possessed the degradation potentials for aromatic compounds. ZM1 was acidophilic with the optimum growth at the initial pH of 3.0. It could adjust pH to desired levels probably by acid production during the cultivation. Notably, at pH 3.0, the strain ZM1 showed a high phenol-degrading capability that almost completely degraded 1100 mg/L of phenol in 120 h with the highest degradation rate of 0.074 g/(g cell dry weight h). Under the same pH, the strain could completely degrade 500 mg/L phenol within 48 h at NaCl concentration up to 10 g/L. The identification of the gene catA by the KEGG analysis, together with the presence of metabolic intermediate of cis, cis-muconic acid detected by gas chromatography-mass spectrometry, confirmed that the strain ZM1 degraded phenol via ortho-cleavage pathway. These findings suggest that the indigenous yeasts strain ZM1 could be exploited as an important member for in-situ biodegradation of aromatic compounds in the extremely acidic environments.

Graphene with atomic layer of sp2-hybridized carbon atoms in a hexagonal structure has attracted multidisciplinary attention since its discovery. Due to the inherent advantages of large specific surface area and abundant functional groups, its derivative graphene oxide (GO) nanomaterials have achieved large-scale development in effective pollution treatment. In the past few years, novel GO-based nanomaterials through coupling with other nanomaterials have been synthesized with significant process and applied for efficient elimination of different kinds of pollutants. This paper aims to summarize recent research results on the excellent removal ability of GO-based nanomaterials for various heavy metal ions in aqueous solutions. The synthesis, adsorption process characteristics and interaction mechanism of the adsorbent are emphasized and discussed. The effects of various environmental conditions are outlined. At last, a brief summary, perspective and outlook are presented. This review is intended to provide some thrilling information for the design and manufacture of GO-based nanomaterials for the elimination of heavy metal ions from wastewater in environmental pollution management.

Ultrafiltration (UF) membrane has recently drawn interest in textile and dyeing wastewater treatment due to its unique advantages of low-cost and large flux. However, its low rejection to dyes and developing appropriate membrane materials remain the major hurdles for its large-scale application. Herein, we developed a novel conductive polyvinylidene fluoride (PVDF)-Ni membrane combined with an external electric field to treat typical dyes. The membrane could be fabricated by a facile and low-cost method. The conductive PVDF-Ni membrane showed favorable rejection rate of Congo red (CR) (100%) and extremely high permeance (137.5 ± 6.8 L m−2 h−1 bar−1). To our knowledge, the permeance has exceeded the maximal literature record for the membranes with similar rejection rates of CR. The novel membrane combined with external electric field also provided a unique aeration mode: in-situ aeration, due to its good electrocatalytic activity for hydrogen evolution reaction (HER) (overpotential of 157 mV at the current density of 10 mA cm−2). Benefit from the in-situ aeration, the PVDF-Ni membrane showed 94% flux recovery after filtration of bovine serum albumin (BSA). Additionally, the PVDF-Ni membrane exhibited evident resistance to dye absorption and antibacterial activity. These versatile proprieties, together with the facile fabrication process, indicated the tremendous application prospect of the fabricated PVDF-Ni membrane for textile and dyeing wastewater treatment.

In recent years, water pollution caused by radionuclides has become a rising concern, among which uranium is a representative class of actinide element. Since hexavalent uranium, i.e. U(VI), is biologically hazardous with high migration, it's essential to develop efficient adsorbents to minimize the impact on the environment. Towards this end, we have synthesized a novel material (GO/PEDOT:PSS) by direct assembling graphene oxide (GO) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) through a facile ball milling method, which shows impressing performance for the immobilization of U(VI). On the basis of the batch experiments, GO/PEDOT:PSS exhibits ionic strength-independent sorption edges and temperature-promoted sorption isotherms, revealing an inner-sphere complexation with endothermic nature. The sorption kinetics can be illustrated by the pseudo-second-order model, yielding a rate constant of 1.09. × 10−2 g mg−1∙min−1, while the sorption isotherms are in coincidence with the Langmuir model, according to which the maximum sorption capacity is measured to be 384.51 mg g−1 at pH 4.5 under 298 K, indicating a monolayer sorption mechanism. In the light of the FT-IR and XPS investigations, the surface carboxyl/sulfonate group is responsible to the chelation of U(VI), indicating that the enhanced sorption capacity may be ascribed to the PSS moiety. These findings can greatly contribute to the design strategy for developing highly efficient adsorbents in the field of radioactive wastewater treatment.

In this study, nanoscale zero-valent iron (nZVI) supported on layered double hydroxide (LDH) composite (LDH@nZVI) was prepared, characterized and applied to U(VI) scavenging in water. Removal of U(VI) as a function of pH, ionic strength, reaction time, initial concentrations of U(VI), and temperature were studied and compared with pure LDH and nZVI, the LDH@nZVI had best U(VI) removal efficiency owning to the excellent synergistic combination of LDH adsorption and nZVI reduction. XPS analysis found that surface oxygen functional groups and surface-bound Fe(II) played a critical role in U(VI) remediation. The large surface areas (334.0 m2/g), abundant functional groups (i.e., M O, C O and OH), rapid kinetics (adsorption equilibrium within 1 h) and excellent adsorption capacities (176 mg/g) indicating that LDH@nZVI can be considered as a potential material for preconcentration of U(VI) from sewage water.

As robust polymeric catalysts, graphitic carbon nitride (g-C3N4) has been known to have great application potential in environmental remediation. However, the mechanisms in the photo-assisted catalytic processes during the reduction or oxidation of pollutants are still difficult to discern and therefore not well studied. In this work, visible-assisted catalytic reduction of hexavalent chromium (Cr(VI)) or oxidation of sulfisoxazole (SIZ) by g-C3N4 with the addition of formic acid (FA) or potassium peroxydisulfate (PS) were systematically investigated. Effects of operation parameters such as g-C3N4 dosage, FA concentration, Cr(VI) concentration, solution pH, PS concentration were studied. The results showed g-C3N4 can be effective and robust catalyst for both the reduction (Yin) and oxidation (Yang) reactions in the environmental remediation. Mechanisms were studied by using electron spin resonance (ESR) spectroscopy. The results revealed the CO 2- is the predominant radical for Cr(VI) reduction in the g-C3N4/FA/Vis system and the SO4- and OH are all the main radicals for the oxidation of SIZ in the g-C3N4/PS/Vis system. The photo-generated carriers by g-C3N4, act as radical initiator, were responsible for the production of the reactive radical species in aqueous solution. This work not only shed a new light on the application of semiconductor polymers for the removal of micropollutants and also will expand the applicability of the polymeric photocatalysts for environmental remediation.

To evaluate the impact of DCAcAm on zebrafish gill, we measure the responses of antioxidant enzyme (superoxide dismutase, SOD), lipid peroxidation (malondialdehyde, MDA), ATPase (Na+ /K+ -ATPase and Ca2+ /Mg2+ -ATP) and histopathological changes of gill in adult zebrafish, after exposed to different concentrations of DCAcAm (0, 1, 10, 100, and 1000 μg L-1 ) for 30 days. Results indicated that DCAcAm first increased and then decreased SOD activity, and DCAcAm also lowered the activities of Na+ /K+ -ATPase and Ca2+ /Mg2+ -ATPase. These results indicated that high affinity of DCAcAm probably be a main factor, which can damage the structures of enzymes, thereby inhibiting the SOD and ATPase activities. Besides, histopathological investigation results also manifested that chronic exposure to DCAcAm can damage the gill tissues, disrupting the normal function of gills. We conclude that chronic exposure to DCAcAm was harmful to organisms, not only influence gill function, but also further cause damage on the gill tissues.

As a class of famous carbon materials, biochars (BCs) and their derivative materials with excellent physicochemical properties and diversified functionalities present great potential in wastewater treatment fields. This review focuses on the latest development in reported biochar-based materials as superior adsorbents or catalysts for removing harmful organic contaminants from wastewater. The construction and properties of biochar-based materials are briefly introduced at the beginning. As one of the major factors affecting the properties of BCs, the wide diversity of feedstocks, such as agricultural and forest residues, industrial by-products as well as municipal wastes, endows BCs different chemical compositions and structures. Woody and herbaceous BCs usually have higher carbon contents, larger surface areas and strong aromaticity, which is in favor of the organic contaminant removal. Driven by the desire of more cost-effective materials, several types of biochar-based hybrid materials, such as magnetic BC composites (MBC), nanometal/nanometallic oxides/hydroxide BC composites and layered nanomaterial-coated BCs, as well as physically/chemically activated BCs, have also been developed. With the help of foreign materials, these types of hybrid BCs have excellent capacities to remove a wide range of organic contaminants, including organic dyestuff, phenols and chemical intermediates, as well as pharmaceutically active compounds, from aquatic solutions. Depending on the different types of biochar-based materials, organic contaminants can be removed by different mechanisms, such as physical adsorption, electrostatic interaction, π–π interaction and Fenton process, as well as photocatalytic degradation. In summary, the low cost, tunable surface chemistry and excellent physical–chemical properties of BCs allow it to be a potential material in organic contaminant removal. The combination of BCs with foreign materials endows BCs more functionalities and broader development opportunities. Considering the urgent demand of practical wastewater treatment, we hope more researches will focus on the applications and commercialization of biochar-based materials.

Heterogeneous activation of peroxymonosulfate (PMS) is one of the most promising techniques for wastewater treatment. Herein, an ingenious system by coupling of photocatalysis and PMS activation was developed, using hollow-structured amorphous prussian blue (A-PB) decorated on graphitic carbon nitride (g-C3N4) as the catalyst. Degradation of bisphenol A (BPA) via the A-PB-g-C3N4 mediated PMS activation under visible light (Vis) was systematically investigated. Astonishingly, it was found that ~ 82.0%, 92.6%, 98.2% and 99.3% of BPA (40 mg/L) were removed within 2, 4, 6 and 7 min, respectively, suggesting the extremely strong oxidizing capacity of the A-PB-g-C3N4/PMS/Vis system. Synergistic effect between the decorated A-PB and the g-C3N4 substrate promoted the Fe(III)/Fe(II) redox cycling and facilitated the charge transfer at the A-PB/g-C3N4 heterojunction interface. As a result, both photocatalysis and heterogeneous activation of PMS were boosted in the A-PB-g-C3N4/PMS/Vis system, leading to the production of large amount of reactive oxygen species (ROS). The various ROS (SO4•–, HO•, •O2– and 1O2) was responsible for the ultrafast degradation of BPA. Moreover, the A-PB-g-C3N4 catalyst also exhibited outstanding reusability and stability, retaining 98.9% of the removal percentage for BPA after five consecutive reaction cycles. This study suggests that the A-PB-g-C3N4 can be an all-rounder to bridge photocatalysis and PMS activation, and shed a new light on the application of multiple ROS for the ultrafast elimination of micropollutants from wastewater.

Age-related macular degeneration (AMD) is the most common cause of visual impairment in developed countries. Inflammation serves a critical role in the pathogenesis of AMD. Gardenia jasminoides is found in several regions of China and is traditionally used as an organic yellow dye but has also been widely used as a therapeutic agent in numerous diseases, including inflammation, depression, hepatic and vascular disorders, which may reflect the variability of functional compounds that are present in Gardenia jasminoides extracts (GJE). To investigate the therapeutic potential of GJE for AMD, ARPE-19 cells were treated with lipopolysaccharide (LPS) or LPS plus GJE. GJE significantly decreased LPS-induced expression of proinflammatory cytokines, including IL-1β, IL-6 and TNF-α. In the in vivo study, GJE inhibited CuSO4-induced migration of primitive macrophages to the lateral line in zebrafish embryos. GJE also attenuated expression of cytokines (IL-1β, IL-6 and TNF-α), NFKB activating protein (nkap) and TLR4 in ARPE-19 cells. The results of the present study demonstrated the anti-inflammatory potential of GJE in vitro and in vivo, and suggested GJE as a therapeutic candidate for AMD.

Although electrode materials based on metal organic frameworks (MOFs) were widely studied in the electrochemistry field, the origin of poor conductivity is still a bottleneck restricting their development. Herein, we constructed a conductive circuit by growing a layer of hydroxide on the surface of the Fe-MOF, and composite materials (Fe-MOF@Ni(OH)2) are applied in the fields of supercapacitor, OER, and electrochemical sensing. Fe-MOF@Ni(OH)2 not only maintains the intrinsic advantages of Fe-MOF, but also improves the electrical conductivity. Fe-MOF@Ni(OH)2 exhibits a high specific capacity of 188 mAh g−1 at 1 A g−1 . The energy density of the asymmetric supercapacitor (Fe-MOF@Ni(OH)2–20//AC) reaches 67.1 Wh kg−1. During the oxygen evolution reaction, the overpotential of the material is 280 mV at 10 mA cm−2, and the Tafel slope is 37.6 mV dec−1. The electrochemical sensing tests showed the detection limit of BPA is 5 μM. Hence, these results provide key insights into the design of multifunctional electrode materials.

Herein, a facile and low-cost method for the preparation of activated carbon from peanut shell was developed for the first time for the fast extraction and determination of Bisphenol A in human urine. Bisphenol A was separated by EC-C18 column (250 mm×4.6 mm, 4 μm) and was detected by VWD, with retention time for qualitative analysis and peak area for quantitation. The parameters, pH values of the urine, adsorbent dose, adsorption time and so on, were optimized to achieve the excellent extraction performance. The detection limit of Bisphenol A in human urine was 1.0 ng · mL−1 (S/N = 3), and the standard curve was linear in the range of 5.0 ng · mL−1˜200.0 ng · mL−1 (r = 0.9993). The average recovery of Bisphenol A was 78.5˜96.2% at three spiked levels in the range of 5.00 ng · mL−1˜200.00 ng·mL−1. The method was proved simple, practical and highly sensitive, which could satisfy the request for the determination of Bisphenol A in human urine.

Given the highly complex recalcitrant nature of synthetic dyes, biological treatment of textile wastewater using efficient bacterial species is still considered as an environmentally friendly manner. In this study, a reactive blue 19 (RB19)-degrading strain, Bacillus sp. JF4, which was isolated by resuscitation-promoting factor (Rpf) strategy, was immobilized into polyvinyl alcohol–calcium alginate–activated carbon beads (JF4-immobilized beads) for RB19 decolorization. Results suggest that the JF4-immobilized beads, which were capable of simultaneous adsorption and biodegradation, showed a high decolorization activity, while they exhibited better tolerability towards high RB19 concentrations. The JF4-immobilized beads could almost completely decolorize 100 mg/L RB19 within 10 d, while only 92.1% was decolorized by free bacteria within 12 d. Further investigation on the equilibrium and kinetics of the adsorption process suggests that the pseudo-second-order model best fit the adsorption kinetics data, and the Freundlich isotherm was the most suitable for the description of the equilibrium data. Notably, the repeated batch cycles indicated that complete decolorization of 100 mg/L RB19 by JF4-immobilized beads can be maintained for at least three cycles without much reduction in efficiency. These findings suggest that immobilizing Rpf-resuscitated strain into beads was an effective strategy for textile wastewater treatment.

2,6-dichlorobenzoquinone (2,6-DCBQ), an emerging disinfection by-production, frequently occurs in reclaimed water and drinking water. However, limited information was available regarding its toxicity. To evaluate its impact, zebrafish at early life stage were exposed to 0, 10, 30, 60, 90, or 120 μg L−1 2,6-BDCQ for 72 h. Our results indicated that 2,6-BDCQ decreased zebrafish's survival rate to 65% and 44% at 90 and 120 μg L−1 treatments and increased its aberration rate to 11% and 26% at 90 μg L−1 and 120 μg L−1 treatments. Besides, 2,6-BDCQ had adverse effect on its oxidative stress (elevated superoxide dismutase activity), lipid peroxidation (increased malondialdehyde levels), DNA damage (increased 8-hydroxydeoxyguanosine contents) and apoptosis (increased caspase-3 activity). Although lower concentrations (≤60 μg L−1) of 2,6-BDCQ didn't exhibit significant effect on its survival development or lipid peroxidation of zebrafish, they induced obvious DNA damage and apoptosis occurrence. These results revealed 2,6-BDCQ caused genotoxicity and cytotoxicity to zebrafish. This study provides novel insight into 2,6-DCBQ-induced toxicity in zebrafish.

Molecular doping has been considered as an effective approach to realize novel conjugated polymers with tailored morphology, electronic structure and performance. Inspired by these merits, a facile strategy is presented to address the problems of insufficient charge separation and low photocatalytic performance of graphitic carbon nitride (g-C3N4). We designed and synthesized molecularly doped g-C3N4 polymers using basic fuchsin (BF), a common organic dye, as the dopant. BF-g-C3N4 exhibited an enhanced performance for the photocatalytic hydrogen production with a H2 evolution rate of 1619 μmol g−1 h−1, which was ∼4.4 times higher than that of pure g-C3N4 under visible light irradiation. The mechanisms for the enhanced photocatalytic activity were systematically investigated by the techniques of ultraviolet-visible-near infrared diffuse reflectance spectroscopy (UV-vis-NIR DRS), ultraviolet photoelectron spectroscopy (UPS), photoluminescence (PL) spectroscopy, and time-resolved fluorescence decay spectroscopy as well as density functional theory (DFT) calculations. The results suggested that the BF doping can improve the light absorption and change the electronic structure of g-C3N4 polymers. The doped BF molecules can create extended band tails that act as electron trap states, leading to an enhanced efficiency for the separation and transportation of photoinduced electron–hole pairs. This study not only sheds new light on the modification of semiconductor polymers via the cost-effective molecular doping approach, but will also expand the applicability of polymeric photocatalysts.

Objective. This systematic review aims to investigate the efficacy and safety of moxibustion for chronic kidney disease (CKD). Methods. Nine databases were searched to identify relevant evidence up to March 8, 2020. Randomized controlled trials (RCTs) that tested moxibustion + basic treatments versus basic treatments alone for patients with CKD and reported, at least, one of the outcomes of interest were included. In the meta-analyses, the mean differences (MDs) and 95% confidence intervals (CIs) were used to measure the effect size. Results. Twenty-three RCTs (n = 1571) with a moderate to high risk of bias were included. The pooled estimates showed that compared with the controls, patients after moxibustion had a significant reduction in serum creatinine (MD −17.34 μmol/L, 95% CI −28.44 to −6.23; I2 = 87%), 24-hour urine protein excretion (MD −0.75 g/h, 95% CI −1.07 to −0.42; I2 = 84%), and blood urea nitrogen (MD −0.63 mmol/L, 95% CI −1.09 to −0.18; I2 = 37%) and a significant improvement in the quality of life (MD 10.18, 95% CI 3.67 to 16.69; I2 = 57%). Moxibustion did not show a significant effect on the estimated glomerular filtration rate (eGFR), creatinine clearance, or hemoglobin. The subgroup analyses showed that a longer course of moxibustion (>8 weeks) and indirect moxibustion had a greater effect on reducing serum creatinine. The effect of moxibustion on blood urea nitrogen changed to be nonsignificant after excluding RCTs with a high risk of bias (MD −0.96 mmol/L, 95% CI −2.96 to 1.03). Only one adverse event of burn was reported. Conclusions. This systematic review suggests that, as an adjuvant therapy, moxibustion may improve serum creatinine, urinary protein excretion, blood urea nitrogen, and quality of life in patients with CKD. Moxibustion may not have effects on eGFR, creatinine clearance, or hemoglobin. The quality of evidence is weakened by the limitations of risk of bias, heterogeneity, and imprecision.

Membrane fouling problem impedes widespread application of polyvinylidene fluoride (PVDF) membrane for water treatment. This study proposed a novel strategy to endow hydrophobic PVDF ultrafiltration (UF) membrane with good antifouling and antibacterial activity. The novel strategy includes 3 steps: polydopamine (PDA) modification, Ag catalytic activation and electroless Cu plating. Via this strategy, copper nanoparticles (CuNPs) were in situ immobilized on PVDF membrane. The adhesive PDA layer not only facilitated to firm attachment of CuNPs, but also increased surface hydrophilicity. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) analyses confirmed successful immobilization of CuNPs, which improved surface hydrophilicity and absolution value of negative zeta potential as compared with the pristine PVDF membrane. Meanwhile, the modified Cu/PDA/PVDF membrane had relatively high conductivity, significantly improving antifouling performance when 0.30 V cm−1 of external electrical field was applied. Antibacterial tests revealed that the modified membrane possessed significantly enhanced antibacterial activity against live E. coli. The novel modification strategy in this study gave important implications for membrane fabrication, and the modified membrane possessed attractive potential in water treatment.

This study assumed that key degraders of functional bacterial community were prone to enter into the viable but non-culturable (VBNC) state under high saline phenolic conditions, and resuscitation-promoting factor (Rpf) could strengthen these degraders for better performances. Based on these assumptions, Rpf was used to enhance salt-tolerant phenol-degrading capability of functional populations in activated sludge. Results suggested that Rpf accelerated the start-up process during sludge domestication, and significantly enhanced salt-tolerant phenol-degrading capability. High-throughput sequencing showed that the resuscitation and stimulation functions of Rpf linked mainly to the genus Corynebacterium within the phylum Actinobacteria, and the genera Proteiniphilum and Petrimonas within the phylum Bacteroidete. These key functional populations contributed to better phenol-degrading capabilities under high salinity conditions. This study indicated that Rpf is a promising additive for improving biological treatment performance of saline phenolic wastewater.

A rapid, sensitive, and economical pipette tip solid phase extraction (PT-SPE) based on graphene oxide/polypyrrole (GO/PPy) coupled with high performance liquid chromatography (HPLC) was developed for the extraction and determination of sulfonamides (SAs) in honey and milk samples. The PT-SPE procedure involved only 3.0 mg of adsorbent, 3 min adsorptive extraction time, and less than 1.0 mL of solvent consumption (sample, washing, or eluent). Under the optimal conditions, good linearities (0.01–10.00 μg mL−1) were obtained with correlation coefficients (r) > 0.9996. The limits of detection (S/N = 3) were in the range of 1.04–1.50 ng mL−1. Meanwhile, the proposed method was successfully applied for the analysis of SAs in honey and milk with average recoveries within 62.3–109.0% and relative standard deviations less than 11.2%. The results demonstrated that the developed PT-SPE-HPLC method was suitable for the analysis of SAs in complex matrix due to its high sensitivity and accuracy.

This study provided a first report on a facile strategy to fabricate superhydrophilic and low-fouling multilayer coatings on polyvinylidene fluoride (PVDF) membrane by layer-by-layer (LBL) assembly of Fe3+ and phytic acid (PA) alternately. Successful modification was verified by scanning electron microscope (SEM) observation and element analysis. It was found that, the resulted PA/Fe@PVDF-OH membrane with five bilayers’ (BLs’) modification performed the optimal antifouling properties under conditions in this study. As compared to the original PVDF-OH membrane, the coated membrane surface possessed super hydrophilicity (water contact angle was 11.34°) and improved negative charge density. Thermodynamic analysis showed that, the changes of interaction energy caused by both of the modified surface thermodynamic properties and morphology were responsible for the improved antifouling performance of the coated membrane. The facile coating strategy, together with the method assessing interaction energy in this study provided a potential solution to optimize LBL assembly technique and to quantitatively tune antifouling ability of membranes.

In this study, a new strategy which blends low-density polyethylene (LDPE), magnesium hydroxide (MH) and lauryl acrylate by electron-beam radiation for production of LDPE-based composites with high performance was proposed. It was found that, MH played main roles in flame retardancy but reduced processing flow and mechanical properties of the composites. Meanwhile, melt flow rate (MFR) increased while viscosity of the composites decreased with lauryl acrylate content increased, facilitating LDPE composites processing. Electron beam radiation could prompt crosslinking of lauryl acrylate, which significantly enhanced the mechanical properties of LDPE composites. Meanwhile, lauryl acrylate addition only slightly decreased the flame retardancy, suggesting that LDPE composites could remain high flame retardancy even when lauryl acrylate content was high. The study highly demonstrated the feasibility to produce LDPE-based composites simultaneously with high flame retardancy and high mechanical properties by the blending strategy provided in this study.

To realize the efficient and complete removal of organic pollutants in waste water, it is highly urgent for scalable synthesis of either self-supported bimetallic nanocatalysts or anchored on carbon-based materials. In this study, a simple one-pot coreduction method was developed for preparing well-dispersed AgPd alloyed nanoclusters uniformly dispersed on reduced graphene oxide (AgPd NCs/rGO) at room temperature by utilizing 5-azacytosine as the capping agent. The nanocomposites were characterized by a set of physical characterizations. The formation mechanism and catalytic mechanism were discussed in some details. Moreover, the prepared AgPd NCs/rGO exhibited dramatically increased catalytic properties towards the reduction of 4-nitrophenol (4-NP) in the presence of NaBH4 when compared to commercial Pd/C (20 wt.%).

The extensive usage of chlorotetracycline (CTC) has caused the persistence of antibiotic residues in aquatic environments, resulting in serious threat to human health and ecosystems. In this study, graphene oxide/titanium dioxide (GO/TiO 2 ) nanocomposite was successfully synthesized via in situ hydrolysis of tetra- n -butyl titanate (Ti(BuO) 4 ) to TiO 2 particles on GO sheets and used as adsorbent for efficient adsorptive removal of CTC from aqueous solution. The prepared GO/TiO 2 was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transformed infrared (FT-IR), Raman spectroscopy and X-ray photoelectron (XPS). Adsorption kinetics, isotherms and thermodynamics were systematically investigated to evaluate the adsorption properties of GO/TiO 2 . Adsorption mechanism was further analyzed by FT-IR, UV–vis and XPS. The results indicated that adsorption kinetics closely followed the pseudo-second order model; the maximum adsorption capacity determined by Langmuir model was 261.10 mg g −1 at 298 K and the thermodynamic studies revealed that the adsorption of CTC onto the GO/TiO 2 was a spontaneous and endothermic process. Moreover, the interactions between CTC and GO/TiO 2 were presumed to be ligand exchange between CTC and TiO 2 , while the π-π electron donor-acceptor interaction, hydrogen bond and cation-π bonding were constructed between CTC and GO. Finally, the prepared GO/TiO 2 was successfully applied for the efficient removal of CTC from Wu River water.

In this work, a scalable and cost-effective approach was developed for the synthesis of magnetic carbon nano-onions (MCNOs) by using iron (III) acetylacetonate modified candle as the raw materials. The candle soot was collected from the burning candle and then subjected to calcination at 800 °C under N2 atmosphere. The obtained MCNOs were further applied as adsorbent for the removal of bisphenol A (BPA) from aqueous solutions. Adsorption of BPA onto the MCNOs was investigated with the influence of initial concentration of BPA, solution pH, and adsorption time. The results demonstrated the adsorption of BPA onto the MCNOs was almost not affected by pH in the range from 5–9. The adsorption isothermal and kinetic's data were better fitted by Langmuir isotherm and pseudo-second-order kinetic model, respectively. Moreover, the MCNOs are easily recycled by using and external magnet and regenerated by simply methanol washing. The results present here not only provide a novel synthetic approach toward low-cost nanocarbons but also revealed the great application potential of the MCNOs for the removal of endocrine disrupting compounds from aqueous solution.

We have developed an analytical method for the extraction and determination of enrofloxacin in milk sample by magnetic solid-phase extraction with metal-organic framework/graphene oxide (Fe3O4/MIL-100(Fe)/GO) as a sorbent coupling to spectrofluorimetry. The prepared Fe3O4/MIL-100(Fe)/GO nanocomposite were characterized by scanning electron microscopy, FT-IR spectroscopy, x-ray diffraction, and vibration sample magnetometer. The parameters affecting extraction efficiency including sample pH, amounts of sorbent, adsorption time, and acidity of elution solvent were optimized systematically. The optimal extraction conditions were as follows: 100.0-mL sample at pH of 8.0, 20.0 mg of Fe3O4/MIL-100(Fe)/GO as sorbent, extraction time of 30 min, and 4.00 mL of 15% (v/v) formic acid in methanol as eluent. A matrix-matched linear relationship (10.00–350.00 μg L−1) between the fluorescence intensity and the concentrations of enrofloxacin was obtained with correlation coefficient (r) = 0.9979. The limit of detection (S/N = 3) and the limit of quantification (S/N = 10) were 0.65 and 2.17 μg L−1, respectively. The relative standard deviations of intraday and interday analysis (n = 5) were 1.64 and 2.86%, respectively. The proposed method was successfully applied for the determination of enrofloxacin in milk sample with recoveries ranged from 85.7 to 106.3%.

The main objective of this study was to assess the effects of disinfection conditions on bromine incorporation into disinfection by-products (DBPs) during chlorination of water with low specific UV absorbance (SUVA). Five classes of DBPs were included: trihalomethanes (THMs), dihaloacetic acids (di-HAAs), trihaloacetic acids (tri-HAAs), dihaloacetonitriles (DHANs) and trihalonitromethanes (THNMs). Results showed that the bromine utilization in DBPs formation was positive related with reaction time, pH and temperature. On the other hand, the bromine substitution factors (BSFs) of DBPs were generally increased with pH (except tri-HAAs) and bromide concentration, but decreased with the reaction time, temperature and chlorine dose. Moreover, the BSFs values varied with DBP classes with the ranking being as following: THNMs≫DHANs≫tri-HAAs>THM≈di-HAAs. These results were mostly similar with the references, yet the pH effect on BSFs as well as the rank of BSFs for different DBP classes may differ with the specific UV absorbance of organic matter.

Herein, a single-step co-reduction aqueous route was designed for preparation of hierarchical AuPt alloy nanochains, firstly using amprolium hydrochloride as a new stabilizing agent and structure-director. The morphology, structure, composition, and size of the products were characterized by a series of technique. The growth mechanism of AuPt nanochains was discussed in details. The AuPt nanochains modified glassy carbon electrode showed the improved analytical performances for determination of nitrite and hydrazine. The linear ranges of nitrite are 0.5-366.4μM and 466.4-2666.4μM for the two segments, and the detection limit is 0.03μM (S/N=3). The linear ranges of hydrazine are 5.0-116.4μM and 166.4-2666.4μM for the two segments, along with the low detection limit of 0.26μM (S/N=3). The performances of AuPt nanochains were superior to those of individual Pt and Au nanoparticles. It is ascribed to the specific hierarchical structures and synergistic effects of the bimetals.

This study provided the first attempt of grafting hydrophobic polyvinylidene fluoride (PVDF) membrane with hydrophilic hydroxyethyl acrylate (HEA) monomer via a radiation grafting method. This grafted membrane showed an enhanced hydrophilicity (10° decrease of water contact angle), water content ratio, settling ability and wettability compared to the control membrane. Interestingly, filtration tests showed an improved dependence of water flux of the grafted membrane on the solution pH in the acidic stage. Atomic force microscopy (AFM) analysis provided in-situ evidence that the reduced surface pore size of the grafted membrane with the solution pH governed such a dependence. It was proposed that, the reduced surface pore size was caused by the swelling of the grafted chain matrix, with the pH increase due to the chemical potential change. It was found that the grafted membrane showed a lower relative flux decreasing rate than the control membrane. Moreover, flux of the bovine serum albumin (BSA) solution was noticeably larger than that of pure water for the grafted membrane. Higher BSA flux than water flux can be explained by the effects of electric double layer compression on the polymeric swelling. This study not only provided a pH-sensitive PVDF membrane potentially useful for various applications, but also proposed novel mechanisms underlying the enhanced performance of the grafted membrane.

Ramie fibers, one of the most important natural fibers in China, are mainly composed of lignin, cellulose, and hemicellulose. As the high lignin content in the fibers results in a prickly texture, the lignin content is deemed to be an important trait of the fiber quality. In this study, the genetic basis of the fiber lignin content was evaluated, resulting in the identification of five quantitative trait loci (QTLs). Three genes, whole_GLEAN_10021050, whole_GLEAN_10026962, and whole_GLEAN_10009464 that were identified on the QTL regions of qLC7, qLC10, and qLC13, respectively, were found to be homologs of the Arabidopsis lignin biosynthetic genes. Moreover, all three genes displayed differential expression in the barks located in the top and middle parts of the stem, where lignin was not being synthesized and where it was being biosynthesized, respectively. Sequence comparison found that these three genes had wide variations in their coding sequences (CDSs) and putative promoter regions between the two parents, especially the MYB gene whole_GLEAN_10021050, whose protein had insertions/deletions of five amino acids and substitutions of two amino acids in the conserved domain. This evidence indicates that these three genes are potentially involved in lignin biosynthesis in ramie fibers. The QTLs identified from this study provide a basis for the improvement of lignin content and fiber quality in ramie breeding. The characterization of the three candidate genes here will be helpful for the future clarification of their functions in ramie.

New synthetic method toward carbon supported catalysts with improved performance is of great importance in direct alcohol fuel cells (DAFCs). Herein, onion-like nanocarbons (OLNCs) were fabricated by using cheap and readily available candle as the raw material. And a facile one-pot and surfactant-free solvothermal approach was developed for the fabrication of PtSn nanoparticles supported on the OLNCs. Transmission electron microscopy (TEM) images showed the highly crystalline PtSn nanoparticles with size of ~2-5 nm were evenly deposited on the surface of the OLNCs. The obtained PtSn/OLNCs nanocomposites with Pt loading of about 10.1% exhibited excellent electrocatalytic activity toward both methanol oxidation reactions (MOR) and ethylene glycol oxidation reactions (EGOR). The current density of PtSn/OLNCs is 2.6 and 2.7 times of the commercial 20 wt% Pt/C toward the MOR and EGOR, respectively, suggesting the great application potential of the PtSn/OLNCs catalyst in DAFCs. The highly electrocatalytic activity of the PtSn/OLNCs may arise from the ultra-small size of the PtSn NPs as well as the large surface area and good electric conductivity of the OLNCs support. This study not only provides an example of the cost-effective fabrication and application of the OLNCs based catalysts and also sheds a new light on the application of the PtSn/OLNCs catalyst in DAFS.

Brominated haloacetic acids (HAAs) are much more cytotoxic and genotoxic than chlorinated one, yet little information is available for their organic precursors. In the present study, 8 water samples were collected in East China: 2 from lakes, 2 from rivers, 2 from reservoirs, a well and a mountain spring. Dissolved organic carbon (DOC), UV absorbance at 254 (UVA), specific UVA (SUVA) and chlorophyll a (Chl-a) were determined in raw water samples; formation of 9 HAA species as well as bromine substitution factor (BSF) were measured in chlorinated water samples. Results showed that water samples located in city generally contained higher levels of DOC (6.4-12.2mg/L) and UVA (0.124-0.194/cm), while those in the country side, low DOC (2.4-5.9mg/L) and UVA (0.061-0.109/cm) levels were observed. Negative relationship (p

The phloem of the stem of ramie (Boehmeria nivea) is an important source of natural fiber for the textile industry. However, the lignin content in the phloem affects the quality of ramie phloem fiber. In this study, the lignin content and related key gene expression levels were analyzed in the phloem and xylem at different developmental periods. The results showed that the relative expression levels of lignin synthesis-related key genes in the xylem and phloem of the stem gradually decreased from the fast-growing period to the late maturation period, but the corresponding lignin content increased significantly. However, the relative expression levels of a few genes were the highest during the maturation period. During all three periods, the lignin content in ramie stems was positively correlated with the expression of genes, including PAL, C4H and 4CL1 in the phenylpropanoid pathway, F5H and CCoAOMT in the lignin-specific synthetic pathway, and CAD in the downstream pathway of lignin synthesis, but the lignin content was negatively correlated with the expression of genes including 4CL3 in the phenylpropanoid pathway and UDP-GT in the shunt pathway of lignin monomer synthesis. The ramie 4CL3 recombinant protein prefers cinnamic acid as a substrate during catalysis, and it negatively regulates lignin synthesis. It is speculated that ramie 4CL3 is mainly involved in the synthesis of ramie flavonoid compounds, and that 4CL1 is mainly involved in lignin synthesis.

Arsenic (As) present in water is a nonignorable environmental issue, even at low concentrations (≤150 μg L−1). To evaluate the toxic effect of low concentrations of As, zebrafish at early life stage were exposed to 0, 25, 50, 75, or 150 μg L−1 AsIII for 120 h. Our results indicated that low concentration of AsIII decreased zebrafish larvae’s survival rate to 85%, 89% and 86% at 50, 75 and 150 μg L−1. Furthermore, low concentrations of AsIII exposure caused oxidative stress (elevated superoxide dismutase (SOD) activity and influenced the mRNA transcriptional levels of Cu/ZnSOD and MnSOD) and damage (increased malondialdehyde levels). Meanwhile, zebrafish larvae regulated the mRNA transcription of metallothionein and heat shock protein 70 to alleviate toxicity caused by AsIII. These results revealed lower concentrations (≤150 μg L−1) of AsIII had a detriment effect on the survival of fish at early life stage, moreover, oxidative stress caused by AsIII posed potential risk for the zebrafish. This study provides novel insight into low concentration AsIII-induced toxicity in zebrafish.

Herein, reduced graphene oxide supported well-dispersed bimetallic AuPt alloy nanodendrites (AuPt ANDs/rGO) were fabricated by a one-pot coreduction approach using ionic liquid (1-aminopropyl-3-methylimidazolium bromide, [APMIm]Br) as the stabilizer and capping agent. There is no any other polymer or seed involved. Characterized measurements include transmission electron microscopy (TEM), high angle annular dark-field scanning TEM (HAADF-STEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The typical samples displayed excellent electrocatalytic activity and durability towards hydrogen evolution reaction (HER) and methanol oxidation reaction (MOR) in contrast with Pt nanocrystals/rGO and commercial Pt/C (50%) catalysts, which make it promising for practical catalysis in energy conversion and storage.

Graphene-based multifunctional composites were prepared by encapsulating of magnetic ZnFe2O4@chitosan (ZnFe2O4@CS) particles into graphene oxide (GO) layers. The obtained ZnFe2O4@CS/GO were characterized using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Adsorption of basic fuchsin (BF) onto the ZnFe2O4@CS/GO was investigated using pH, adsorption time, initial BF concentration and temperature. Kinetic data and adsorption isotherms were better fitted by a pseudo-second-order kinetic model and Langmuir isotherm model, respectively. The values of activation parameters such as free energy (ΔG, −14.02 to −16.56 kJ mol−1), enthalpy (ΔH, 23.27 kJ mol−1) and entropy (ΔS, 127.75 J mol−1 K−1) were calculated, suggesting that the adsorption was a spontaneous, favorable and endothermic process in nature. The results demonstrated that the ZnFe2O4@CS/GO composites are potentially suitable materials for the removal of organic dyes from large volumes of wastewater.

Herein, a facile and straightforward green-assembly approach was developed for preparation of nitrogen and sulphur co-doped three-dimensional (3D) graphene hydrogels (N/S-GHs) with the assistance of glutathione. Specifically, graphene oxide is reduced and assembled into 3D porous nanostructures with glutathione as the reducing agent and modifier for its intrinsic structure, along with the nitrogen and sulphur sources in the synthetic process. As expected, the as-obtained N/S-GHs demonstrated superior adsorption performances for organic dyes (e.g., methylene blue, malachite green, and crystal violet) in aqueous media. This work provides new insight for the green-assembly of 3D porous nanomaterials as adsorbent and their promising applications in water treatment.

Herein, we reported the direct synthesis of core-shell AuPt@Pt nanocrystals supported on reduced graphene oxide (AuPt@Pt NCs/rGO) in aqueous media, with poly(1-vinyl-3-ethylimidazolium bromide) (poly(ViEtlmBr)) as a structure-directing agent, without any specific additive (e.g., seed, organic solvent or template). The as-synthesized AuPt@Pt NCs/rGO exhibited improved electrocatalytic performances towards ethylene glycol oxidation reaction (EGOR) in contrast with commercial Pt/C (20%) catalyst in acidic and alkaline electrolytes. Meanwhile, the catalyst displayed enhanced catalytic activity for hydrogen evolution reaction (HER) with the positive onset potential (−25 mV) and a small Tafel slope (33 mV decade −1 ) relative to Pt/C catalyst (−18 mV, 31 mV decade −1 ) in 0.5 M H 2 SO 4 , along with the positive onset potential (−43 mV) and a small Tafel slope (73 mV decade −1 ) as compared with Pt/C catalyst (−42 mV, 85 mV decade −1 ) in 0.5 M KOH.

Graphene-Fe3 O4 nanoparticles were prepared using one-step solvothermal method and characterized by X-ray diffraction, FTIR spectroscopy, scanning electron microscopy, and vibrating sample magnetometry. The results demonstrated that Fe3 O4 nanoparticles were homogeneously anchored on graphene nanosheets. The as-synthesized graphene-Fe3 O4 nanoparticles were employed as sorbent for magnetic solid-phase extraction of sulfonamides in milk prior to capillary electrophoresis analysis. The optimal capillary electrophoresis conditions were as follows: 60 mmol/L Na2 HPO4 containing 2 mmol/L ethylenediaminetetraacetic acid disodium salt and 24% v/v methanol as running buffer, separation voltage of 14 kV, and detection wavelength of 270 nm. The parameters affecting extraction efficiency including desorption solution, the amount of graphene-Fe3 O4 nanoparticles, extraction time, and sample pH were investigated in detail. Under the optimal conditions, good linearity (5-200 μg/L) with correlation coefficients ≥0.9910 was obtained. The limits of detection were 0.89-2.31 μg/L. The relative standard deviations for intraday and interday analyses were 4.9-8.5 and 4.0-9.0%, respectively. The proposed method was successfully applied to the analysis of sulfonamides in milk samples with recoveries ranging from 62.7 to 104.8% and relative standard deviations less than 10.2%.

A convenient, reliable and highly sensitive assay for alkaline phosphatase (ALP) activity in the real-time manner is developed based on β-cyclodextrin-modified carbon quantum dots (β-CD-CQDs) nanoprobe through specific host-guest recognition. Carbon quantum dots were first functionalized with 3-aminophenyl boronic acid to produce boronic acid-functionalized CQDs, and then further modified with hydropropyl β-cyclodextrins (β-CD) through B-O bonds to form β-CD-CQDs nanoprobe. p-Nitrophenol phosphate disodium salt is used as the substrate of ALP, and can hydrolyze to p-nitrophenol under the catalysis of ALP. The resulting p-nitrophenol can enter the cavity of β-CD moiety in the nanoprobe due to their specific host-guest recognition, where photoinduced electron transfer process between p-nitrophenol and CQDs takes place to efficiently quench the fluorescence of the probe. The correlation between quenched fluorescence and ALP level can be used to establish quantitative evaluation of ALP activity in a broad range from 3.4 to 100.0U/L with the detection limit of 0.9U/L. This assay shows a high sensitivity to ALP even in the presence of a very high concentration of glucose. This study demonstrates a good electron donor/acceptor pair, which can be used to design general detection strategy through PET process, and also broadens the application of host-guest recognition for enzymes detection in clinical practice.

Porous reduced graphene oxide hydrogels (RGOH), especially as supports for immobilizing metallic nanocrystals have attracted great attention in advanced nanomaterials, which have broad applications in catalysis, sensing and electric/optical devices. Herein, uniform core-shell AuPd@Pd nanocrystals supported on three-dimensional (3D) porous N-doped RGOH (AuPd@Pd NCs/N-RGOH) are facilely prepared by combining hydrothermal treatment with wet-chemical co-reduction. Ethylenediamine (EDA) is used as the nitrogen source and assembly agent for N-RGOH under hydrothermal conditions, and also as the structure-director for AuPd@Pd NCs during the wet-chemical co-reduction process. The nanocomposites display enhanced catalytic activity and stability for methanol oxidation reaction (MOR) in comparison with Pd NPs/N-RGOH and commercial Pd-C catalysts, owing to the unique structure and abundant nitrogen of N-RGOH, along with the synergistic effects between N-RGOH and AuPd@Pd NCs.

The miniaturization of self-assembled solid phase extraction (m-SASPE) based on graphene oxide/chitosan (GO/CS) coupled with liquid chromatography-ultraviolet detection was developed for rapid screening of five sulfonamide residues in egg and honey. GO/CS was synthesized by solution blending method and characterized by FT-IR, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Parameters that affected extraction efficiency including sample pH , amount of the GO/CS, elution solvent and rotation speed were optimized in detail. Under the optimal conditions, good linear relationships between the peak area and the concentrations of the analytes were obtained. The linear ranges were 0.01–10.00 μg g −1 with correlation coefficients (r) ≧ 0.9989. The method detection limits (MDLs) were in the range of 0.71–0.98 ng g −1 . The relative standard deviations (RSDs) of intra- and inter-day analysis were less than 3.5 and 7.1%, respectively. The proposed method was successfully applied for the analysis of sulfonamide residues in egg and honey. The average recoveries for two samples spiked at levels from 0.02 to 2.0 μg g −1 were in the range of 75.3–105.2% with RSDs less than 13.5%.

A one-pot wet-chemical co-reduction route is designed for preparation of porous dandelion-like Au@Pd core-shell nanostructures in-situ grown on reduced grapheneoxide (Au@Pd/rGO) without using any premade seed. Cetyltrimethylammonium chloride (CTAC) and iodide ion (I−) play important roles in this synthetic procedure. Particularly, the Pd shell thickness, particle size, composition and catalytic activity can be tuned by adjusting the concentrations of I−. The effects of composition and structure of the as-synthesized nanocomposites on the catalytic performance are investigated. The dandelion-like Au@Pd/rGO exhibited higher catalytic activity and stronger tolerance to carbonaceous species poisoning for methanol oxidation reaction (MOR) in contrast with Pd/rGO and commercial Pd/C catalysts in alkaline media. This strategy offers a new approach for controlled synthesis of novel nanocatalysts with enhanced catalytic performances in fuel cell.

Porous cuprous oxide nanospheres were deposited on reduced graphene oxide (pCu2O NS-rGO) by a solvothermal approach that uses hexadecyltrimethylammonium bromide as the capping agent and L-glutamic acid as the reducing agent. The nanomaterial was characterized by transmission electron microscopy, Raman spectroscopy, thermogravimetry, and electrochemical methods. A glassy carbon electrode was modified with pCu2O NS-rGO, and the respective electrode displays a well expressed oxidation peak for dopamine (DA) located at 160 mV (vs. SCE). It also gives a strong peak for uric acid (UA) which is separated from the DA peak by 130 mV (vs. SCE). No signals can be detected for ascorbic acid (AA) in concentrations up to 2.0 mM. The findings are exploited in a method for simultaneous determination of UA and DA. The linear ranges are from 1.0 to 138 μM for UA, and from 0.05 to 109 μM for DA even in the presence of relatively high concentrations of AA. The detection limits are 112 nM for UA and 15 nM for DA (at an S/N ratio of 3).