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In this study, a functionalized Co3O4-Bi2O3-Ti catalytic membrane (CBO-Ti-M) was prepared and applied for removing organic pollutants via activating peroxymonosulfate (PMS) in the dead-end filtration mode. Characterizations including scanning electron microcopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) showed that the Co3O4-Bi2O3 catalyst was successfully supported on the Ti membrane. The CBO-Ti-M /PMS system could efficiently remove various organic pollutants such as sulfamethoxazole, methyl orange, bisphenol A and methylene blue, achieving removal efficiencies of 98.0%-99.5%. The effects of PMS concentration, flow rate and solution environment on degradation efficiency were investigated in detail. Furthermore, quenching experiments, electron spin resonance (ESR) and in-situ open circuit potential (OCP) tests collectively demonstrated that singlet oxygen as well as the non-radical electron transfer pathway mainly contributed in the reaction mechanism. The synergistic effect of Co and Bi was illustrated according to XPS results, and the possible degradation pathway of MB was proposed based on LC-MS analysis. Reusability test showed that pollutant removal efficiency with the CBO-Ti-M /PMS system remained stable in four runs and limited metal leaching was observed.

Compared with carbon nanotube (CNT) and graphene (GE) aerogels, the synthesis of three-dimensional (3D) carbon nanofiber (CNF) aerogels that are highly compressible, resilient under cyclic strains, and creep and fatigue resistant remains extremely challenging. Herein, a revolutionary green and scalable biosynthesis is presented, by which a novel 3D CNF aerogel derived from natural bacterial cellulose (BC) decorated with its mother bacteria is created. The as-prepared CNF aerogel possesses excellent mechanical resilience, ultra-low energy loss coefficient, and outstanding cycling stability, which are by far among the best performances for CNT and GE aerogels reported thus far. Furthermore, the CNF aerogel exhibits excellent creep and fatigue resistance and sensitive electrical conductivity change upon compression. Surprisingly, the as-prepared 3D CNF aerogel exhibits superhydrophilicity. These superb properties are attributed to the existing carbonized bacteria in the carbonized BC matrix that serve as crosslinks to strengthen the aerogel and buffers to store deformation energy. This study presents a breakthrough method for the construction of superb and cost-effective 3D CNF aerogel from natural biomass material.

The present study demonstrates a series of environmentally friendly lanthanum and titanium doped mesoporous bioactive glass with adsorption, photocatalytic and regeneration performance for methylene blue via the sol-gel method. The materials were studied by XRD, XPS, TEM and BET. The influence of the initial dye concentration, contact time, solution pH, temperature, photocatalytic performance and regeneration performance of this glass adsorbed methylene blue were investigated. It is shown that the Freundlich and Langmuir adsorption isotherms can be used to study the equilibrium of methylene blue removal process by bioactive glass. Another test on photocatalytic degradation performance and reproduction performance of the materials by removing methylene blue. This article has its potential in treatment of dyeing waste water as it improves structure and performance by adding La and Ti to mesoporous bioactive glass.

The efficient conversion of CO2 to chemical fuels driven by solar energy is still a challenging research area in photosynthesis, in which the conversion efficiency greatly relies on photocatalytic ...

In this study, the electrochemical dechlorination of triclosan in aqueous solution on palladium/polypyrrolereduced graphene oxide/foamed nickel composite electrode (Pd/PPy-rGO/foam-Ni electrode) was investigated. The influences of the applied current, reaction temperature and the initial concentration of triclosan solution on triclosan dechlorination efficiency were studied. The triclosan can be completely removed within 180 min under the conditions of the dechlorination current of 7 mA and dechlorination temperature of 40 °C when the initial concentration of triclosan was 50 mg · L–1.

A fluorescent monolayered two‐dimensional polymer (2DP) containing both tetraphenylethylene (TPE) and imine linkages is synthesized at air‐water interface using the Langmuir‐Blodgett method. We designed TPE‐based monomers with long distances between the TPE and the imine linkages to avoid the charge transfer and therefore keep the fluorescence. A monolayered 2DP provided with more than 104 μm2 in domain size and around 0.8 nm thickness was obtained through a successive Schiff base reaction at air‐water interface. The nanostructures and fluorescent property of 2DP films were characterized by optical microscopy, SEM, TEM, AFM and fluorescence spectrum. Most importantly, the tip‐enhanced Raman spectroscopy (TERS) was utilized here to confirm the success of the polycondensation of monolayered 2DP., A large‐area, monolayered fluorescent two‐dimensional polymer containing both TPE and imine linkage was obtained on the air‐water interface (Langmuir‐Blodgett method). The tip‐enhanced Raman spectroscopy (TERS) was utilized here to confirm the success of the polycondensation of monolayered 2DP. The long distance between the TPE and the imine linkages aviod the charge transfer and therefore keep the fluorescence.

In this study, a new composite electrode of palladium (Pd) nanoparticles dispersed on polypyrrole-reduced graphene oxide (PPy-rGO) loaded on foam-nickel was achieved by galvanostatic method. Characterization of structures, morphology and crystallinity of the synthesized materials were investigated by scanning electron microscopes (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy and electrochemical impedance spectroscopy (EIS). The results of XPS and XRD demonstrated Pd showed primarily as Pd0. From SEM and TEM results, we had seen that Pd nanoparticles were dispersible well on the composite electrode. Raman spectroscopy was used to show the state of graphene oxide and further demonstrated that PPy and rGO had existed of on the foam Ni matrix. The data of EIS also suggested the charge transfer of the new composite electrode decreased compared to Pd/PPy/foam-Ni and PPy/foam-Ni composite electrodes. The effect of the electropolymerization potential on Pd/PPy-rGO/foam-Ni electrode for removing triclosan (TCS) was examined. It was found that the removal efficiency of TCS on the composite electrode could reach 100% at electropolymerization potential of 0.7 V and reaction time of 100 min. Keywords: Pd/PPy-rGO/foam-Ni electrode, Triclosan, Electrocatalytic hydrodechlorination, Potentiostatic electropolymerization, Applied potential

Clubroot disease, caused by Plasmodiophora brassicae, is a serious soil-borne disease of Brassica crops worldwide. Pakchoi is one of the most important cruciferous vegetable crops and commonly infected by P. brassicae. To date, the physiological changes and mechanism of pakchoi in response to P. brassicae are largely unknown. In this study, seedlings of two pakchoi cultivars, cv. Xinxiaqing (a clubroot-susceptible cultivar) and Yanlong (a less susceptible cultivar than Xinxiaqing), were inoculated with P. brassicae. Results showed that infected roots were enlarged and changed into club shape galls. Fresh root weight, relative electrical conductivity, the activity of lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH) in infected roots were significantly induced. In contrast, a significant reduction of root length, root function, and the activity of succinic dehydrogenase (SDH), catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) were observed in diseased roots. Interestingly, activities of malate dehydrogenase (MDH) and peroxidase (POD) in S1 and S2 plant roots were increased and decreased in S3 plant roots. Additionally, infected Xinxiaqing roots showed more serious disease symptoms than Yanlong, and the antioxidant enzyme activities were lowered in Xinxiaqing roots compared with those in infected Yanlong roots, indicating the importance of these enzymes in plant resistance against clubroot disease.

Terahertz time-domain spectroscopy has been widely applied in performing dielectric analysis for various materials. However, air voids trapped in samples will significantly affect the characterization. In this study, the refractive index of mixture samples consisting of iron trioxide and polytetrafluoroethylene in five different mass ratios were measured with terahertz time-domain spectroscopy. In order to extract the intrinsic refractive index of iron trioxide, the effective medium model of CRI was then applied to remove refractive index of PTFE in the sample. The extracted refractive indices were presented as a variable parameter decrease with the increase of iron trioxide content, which also corresponds to the increase of air voids in the tablets. The correlation between trapped air voids and analyte composition roots from the coarse rust particles used in pellets compression. This study shows that the influence of air porosity should be considered when terahertz waves are utilized to characterize dielectric property of coarse material.

A sulfur-rich graphdiyne (TTF-GDY) material containing electrochemically active unit of tetrathiafulvalene was successfully synthesized at the liquid/liquid interface under mild conditions. The extended two-dimensional (2D) π-conjugated framework contains large in-plane cavities to accommodate defined sulfur elements and precise sulfur content. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) characterizations demonstrated that the TTF-GDY adopted the layered structures. X-ray photoelectron spectroscopy (XPS), Raman spectrum, selected area electron diffraction (SAED), crystal modeling, and molecular-mechanics-based calculation further confirmed the proposed framework structure and the expected chemical compositions. Considering the unique structure and sulfur-rich characteristic, we then applied this material as an electrode in lithium battery applications. Due to the unique 2D framework structure, the TTF-GDY exhibited a high specific capacity of 837.6 mAh/g, particularly having a robust long-term stability under the high current density. These results demonstrated that such a sulfur-rich TTF-GDY, as a novel electrochemical material would have great application potential in energy fields.

Novel composite magnetic microspheres containing chitosan and quaternary ammonium chitosan derivative (CHMMs) were prepared by inverse suspension method, and used for the methyl orange (MO) removal from aqueous solutions. The CHMMs were characterized by a scanning electron microscope, a transmission electron microscope, and Fourier transform infrared spectroscopy, respectively. Compared with the chitosan beads, the incorporation of quaternary ammonium chitosan derivative significantly reduced the particle size. The MO adsorption by CHMMs was investigated by batch adsorption experiments. The adsorption kinetics was conformed to the pseudo second-order kinetics equation. The adsorption isotherm followed the Langmuir model better than the Freundlich model and the calculated maximum MO adsorption capacity was 266.6 mg·g−1 at 293 K. Thermodynamic studies indicated that the MO adsorption was endothermic in nature with the enthalpy change (∆ H°) of 99.44 kJ·mol−1. The CHMMs had a stable performance for MO adsorption in the pH range of 4–10, but high ionic strength deteriorated the MO removal due to the shielding of the ion exchange interaction. A 1 mol·L−1 NaCl solution could be used to regenerate the exhausted CHMMs. The proposed CHMMs can be used as an effective adsorbent for dye removal or recovery from the dye wastewater.

The industrial processing of shrimp produces massive quantities of solid waste that is a notable source of animal protein, chitin, carotenoids, and other bioactive compounds that are not appropriately utilized. In the present study, chitin and protein extraction from shrimp head with autolysis and fermentation using Bacillus licheniformis were investigated. The results showed that when shrimp heads were autolyzed with a natural pH at 50°C for 4 h, the total amino acid nitrogen in the supernatant was 5.01 mg mL−1. Then, when a 50% (v/m) inoculum of the hydrolysate was incubated at 60°C for 10 h, a deproteinization rate of 88.3% could be obtained. The fermented supernatant was processed into a dry protein powder, while the residues were demineralized by 10% citric acid for chitin. The recovered protein powder contained 5.5% moisture, 11.5% ash, and 66.7% protein, while the chitin contained 3.5% moisture, 2.1% ash, and 3.1% protein. In addition, amino acids, minerals, heavy metals, the degree of acetylation, microstructure, and Fourier-transform infrared (FT-IR) spectroscopy results were analyzed. Furthermore, the statistics of the large scale trial after treatment with 20 kg of shrimp heads were analyzed. Thus, this work made the shrimp waste utilization environmentally sound and valuable.

In the present work, palladium/polyaniline/foamed nickel (Pd/PANI/Ni) composite electrode was successfully constructed via two-step galvanostatic electropolymerization method. Subsequently, physicochemical properties such as apparent morphologies, crystalline structure, surface state and electrochemical property were characterized through scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron microscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and Electrochemical impedance spectroscopy (EIS). The effects of the polymerization current, temperature and reaction time of galvanostatic electropolymerization on the composite electrode for the electrochemical dechlorination of 2,4-dichlorophenol (2,4-DCP) were examined. All results indicated that PANI in the Pd/PANI/Ni composite electrode existed in the form of needle-shaped, while nulvalent Pd particles dispersed well as clusters in the network on PANI. Under optimal conditions, in which PANI polymerized on electrode structure with the polymerization current of 24 mA, temperature of 0 °C and time of 20 min, respectively, a 89.1% removal rate of 2,4-DCP could be achieved. Finally, electrochemical dechlorination pathway was investigated and the main dechlorination product was phenol. The composite electrode possessed good stability and excellent electrocatalytic dichlorination performance.

The etiology and pathogenesis of Alzheimer's disease (AD) are not fully understood. Thus, there are no drugs available that can provide a cure for it. We and others found that DNA polymerase-β (DNA pol-β) is required for neuronal death in several neurodegenerative models. In the present study, we tested the effect of a DNA pol-β inhibitor 2',3'- Dideoxycytidine (DDC) in AD models both in vitro and in vivo. DDC protected primary neurons from amyloid-β (Aβ)-induced toxicity by inhibiting aberrant DNA replication mediated by DNA pol- β. Chronic oral administration of DDC alleviated Aβ deposition and memory deficits in the Tg2576 mouse model of AD. Moreover, DDC reversed synaptic loss in Tg2576 mice. These results suggest that DDC represents a novel therapeutic agent for the treatment of AD.

Fructosyltransferases have been used in the industrial production of fructooligosaccharides (FOS). However, it is still not possible to explain the difference in FOS production based on the variations observed in the FOS synthesizing enzymes of A. niger. In the present study, a novel fructosyltransferase (FT-A) from A. niger TCCC41686 with high FOS synthesis ability was characterized. The FT-A gene was obtained and expressed in Pichia pastoris. A homology model of FT-A showed that the changes of residues identified outside the conserved domains were found to have an effect on its characteristics and its FOS-synthesis capacity. The optimal activity of the recombinant FT-A was observed at 50 °C and pH 6.0, and it was stable below 50 °C and over the range of pH 3.0–11.0. The Km and Vmax values of FT-A were 151.13 g L−1 and 6.55 g L−1 min−1, respectively. The production of FOS using the recombinant FT-A remained above 60% during 50–80 min of synthesis based on sucrose as substrate. The novel fructosyltransferase (FT-A) investigated in this study can potentially be applied for the efficient industrial production of FOS. The results also provide more valuable information for explaining the relationship between the structure and function of the FT-A.

A water-soluble two-dimensional supramolecular organic framework (2D SOF) was prepared via self-assembly of cucurbit[8]uril (CB[8]) and a three-arm flat linker molecule, which contains a benzene ring as the core and three Brooker's merocyanine (BM) analogs as arms. The strong host–guest interactions between BM and CB[8] and the directional head-to-tail stacking modes between the BM arms synergistically led to the formation of a 2D SOF. The structure of the 2D SOF was verified by 1H NMR, 2D 1H NMR NOESY, and DLS characterizations, while the monolayer structure was characterized by Cryo-TEM and AFM measurements. The 2D SOF exhibited an obvious AIE enhancement effect in H2O. In addition, DNA induced photoluminescence enhancement was observed for the monomer. As a result, this AIEgen-based 2D SOF could feature not only as a cell visualizer but also as a tracker for the nucleus in biological imaging due to the dynamic assembly process.

Sprague Dawley rats were exposed to beryllium sulfate (BeSO4), and proteomic and bioinformatic techniques were applied to screen for differentially expressed proteins in their lung tissue and serum. A total of 12 coexpression modules were constructed for 18 samples with 2333 proteins. Four modules were found to have significant differences in the regulation of protein coexpression modules in the serum following exposure to BeSO4. A further three modules had significant differences in the regulation of protein coexpression modules in the lung tissues. Five modules with good correlation were obtained by calculating the gene significance and module membership values, whereas these module Hub proteins included: Hspbp1, Rps15a, Srsf2, Hadhb, Elmo3, Armt1, Rpl18, Afap1L1, Eif3d, Eif3c, and Rps3. The five proteins correlating highest with the Hub proteins in the lung tissue and serum samples were obtained using string analysis. KEGG and GO enrichment analyses showed that these proteins are mainly involved in ribosome formation, apoptosis, cell cycle regulation, and tumor necrosis factor regulation. By analyzing the biological functions of these proteins, proteins that can be used as biomarkers, such as Akt1, Prpf19, Cct2, and Rpl18, are finally obtained.

Beryllium and its compounds are systemic toxicants that are widely applied in many industries. Hydrogen sulfide has been found to protect cells. The present study aimed to determine the protective mechanisms involved in hydrogen sulfide treatment of 16HBE cells following beryllium sulfate-induced injury. 16HBE cells were treated with beryllium sulfate doses ranging between 0 and 300 μM BeSO4 . Additionally, 16HBE cells were subjected to pretreatment with either a 300 μM dose of sodium hydrosulfide (a hydrogen sulfide donor) or 10 mM DL-propargylglycine (a cystathionine-γ-lyase inhibitor) for 6 hr before then being treated with 150 μM beryllium sulfate for 48 hr. This study illustrates that beryllium sulfate induces a reduction in cell viability, increases lactate dehydrogenase (LDH) release, and increases cellular apoptosis and autophagy in 16HBE cells. Interestingly, pretreating 16HBE cells with sodium hydrosulfide significantly reduced the beryllium sulfate-induced apoptosis and autophagy. Moreover, it increased the mitochondrial membrane potential and alleviated the G2/M-phase cell cycle arrest. However, pretreatment with 10 mM DL-propargylglycine promoted the opposite effects. PI3K/Akt/mTOR and Nrf2/ARE signaling pathways are also activated following pretreatment with sodium hydrosulfide. These results indicate the protection provided by hydrogen sulfide in 16HBE cells against beryllium sulfate-induced injury is associated with the inhibition of apoptosis and autophagy through the activation of the PI3K/Akt/mTOR and Nrf2/ARE signaling pathways. Therefore, hydrogen sulfide has the potential to be a promising candidate in the treatment against beryllium disease.

Increasing evidence suggests that oxidative damage and neuroinflammation play a critical role in the pathogenesis of post-stroke depression (PSD). These pathologic processes are tightly regulated by the NF-E2-related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway. The synthetic triterpenoid, 2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im), is a potent Nrf2 activator. This study investigated whether CDDO-Im exhibited antidepressant-like activity and elucidated its protective mechanisms in a rat model of PSD, which was produced by middle cerebral artery occlusion (MCAO) followed by 28 days of chronic unpredictable mild stress (CUMS) in conjunction with solitary housing. The results demonstrated that CDDO-Im treatment markedly improved the depressive-like behaviors and reduced neuronal cell loss in the hippocampus, through decreasing the malondialdehyde (MDA) content (indicative of lipid peroxidation), superoxide dismutase (SOD), NF-kB activation, interleukin-6 (IL-6) and interleukin-1b (IL-1β) in PSD rats. CDDO-Im treatment alleviated the oxidative stress and inflammatory response in PSD rats by promoting Nrf2 nuclear import and increasing the protein levels of Nrf2 downstream target genes, including heme oxygenase-1(HOMX1) and, quinone oxidoreductase-1(NQO1).These findings suggested that CDDO-Im treatment exhibited antidepressant-like effects and protected PSD rats from oxidative and inflammatory injury via the Nrf2/ARE pathway. Therefore, CDDO-Im treatment is worthy of further study.

Clubroot is one of the most serious diseases affecting Brassicaceae plants worldwide. However, there is no effective control method for clubroot. Salicylic acid (SA) is a plant hormone that plays a critical role in plant defense. In our study, we found the disease severity of a clubroot-sensitive cultivar of pakchoi, Xinxiaqing, was reduced with 0.6mM exogenous SA after the infection of P. brassicae. To investigate the mechanism of SA-reduced disease severity against clubroot, then we analyzed the plant growth, alteration of antioxidant enzyme system, and related gene expression of Xinxiaqing. Results showed that the clubroot incidence rate and disease index were decreased after being treated with 0.6 mM exogenous SA. Furthermore, plant growth, reactive oxygen species (ROS) contents, and membrane lipid peroxidation were changed. The activities of antioxidant enzymes, including superoxide dismutase (SOD), ascorbic acid-peroxidase (APX), catalase (CAT), and glutathione reductase (GR), were increased. Additionally, the production rates of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2·–) were also inhibited. The expression levels of genes, encoding SOD, APX, CAT, and GR, were increased. By summering all results, we conclude that 0.6 mM SA contributes to the reduction of disease severity to clubroot by increasing the activities of antioxidant enzymes, abilities of osmotic regulation, and ROS scavenging to reduce the clubroot-induced damage in pakchoi.

Transphosphatidylation catalyzed by phospholipase D has gained increasing attention for producing phosphatidylserine (PS), which can be used in functional food and medicine. In this study, we investigated the effects of six signal peptides on the secretion of PLD (PLDsa) from Streptomyces antibioticus TCCC 21059 in the food-grade GRAS bacterium Bacillus subtilis. It indicated that the optimal signal peptide DacB with an Ala-X-Ala sequence motif at the C-terminus showed the highest secretory expression ability, resulting in increased production of 2.84 U/mL PLDsa. Then PLDsa was immobilized on the epoxy-based carriers, and one of these carriers allowed PLDsa loading of up to 2.7 mg/g. The immobilized PLDsa was more stable over a wide range of pH value (4.5–7.5) and temperature (16 °C–60 °C) than free PLDsa. Subsequently, the synthesis of PS from soybean phosphatidylcholine (PC) was carried out in purely aqueous solution using immobilized PLDsa, leading to a high yield of 65%. The immobilized PLDsa catalyst maintained a relative PS production of 60% after 5 recycles. Notably, the use of toxic solvent was completely eliminated in the whole process, which would be more profitable for the application of PS.

This current study explored the effects of fine particulate matter (PM2.5) on deoxyribonucleic acid methylation in human bronchial epithelial cells. Human bronchial epithelial cells were exposed to PM2.5 for 24 h after which, deoxyribonucleic acid samples were extracted, and the differences between methylation sites were detected using methylation chips. Subsequent gene ontology functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed for the differential methylation sites. Functional epigenetic modules analysis of the overall differential methylation site interactions was also conducted. A total of 127 differential methylation sites in 89 genes were screened in the PM2.5 10 μg/ml group, of which 55 sites demonstrated increased methylation, with methylation levels decreasing in a further 72 sites. Following an exposure of 50 μg/ml PM2.5, a total of 238 differentially methylated sites were screened in 168 genes, of which methylation levels increased in 127 sites, and decreased in 111. KEGG analysis showed that the top 10 enrichment pathways predominantly involve hepatocellular carcinoma pathways and endometrial cancer pathways, whereas functional epigenetic modules analysis screened eight genes (A2M, IL23A, TPIP6, IL27, MYD88, ILE2B, NLRC4, TNF) with the most interactions. Our results indicate that exposure to PM2.5 for 24 h in human bronchial epithelial cells induces marked changes in deoxyribonucleic acid methylation of multiple genes involved in apoptosis and carcinogenesis pathways, these findings can provide a new direction for further study of PM2.5 carcinogenic biomarkers.

Lysophosphatidic acid is a small extracellular signaling molecule, which is elevated in pathological conditions such as ischemic stroke and traumatic brain injury (TBI). LPA regulates the survival of neurons in various diseases. However, the molecular mechanisms underlying LPA-induced neuronal death remain unclear. Here we report that LPA activates LPA1 and LPA2 receptors, and the downstream MAPK pathway to induce the apoptosis of PC12 cells through mitochondrial dysfunction. LPA elicits the activation of ERK1/2, p38, and JNK pathways, decreases the expression of Bcl2, promotes the translocation of Bax, and enhances the activation of caspase-3, resulting in mitochondrial dysfunction and cell apoptosis. This process can be blocked by LPA1 receptor antagonist and LPA2 receptor antagonist and MAPK pathway inhibitors. Our results indicate that LPA1 receptor, LPA2 receptor and MAPK pathway play a critical role in LPA-induced neuronal injury. LPA receptors and MAPK pathways may be novel therapeutic targets for ischemic stroke and TBI, where excessive LPA signaling exist.

A dual-response ratiometric fluorescence imprinted sensor based on visible/near-infrared emission was established for ultrasensitive, selective and visual detection 4-nitrophenol (4-NP). The molecularly imprinted polymer was incorporated in the ratiometric sensing system consisting of visible emission carbon dots@zeolitic imidazolate framework-8 (CDs@ZIF-8) and near-infrared emission cadmium telluride (CdTe) quantum dots. The CDs@ZIF-8 enhanced the emission of CDs and the fluorescence sensing performance. Compared to short wavelength of fluorophore, the near-infrared emission CdTe is less interference caused by auto-fluorescence of sample. The ratiometric fluorescence imprinted sensor exhibited dual response for 4-NP at 420 nm and 703 nm and a wide concentration response range. Moreover, a good linear response was existed in the two concentration ranges of 0.1 pM–3.0 pM and 0.05 μM–30 μM with the detection limit of 0.08 pM and 0.05 μΜ, respectively. Significantly, the fluorescence color changes can be observed from purple to pink to red with the naked eye. The fluorescence quenching mechanism of the ratimetric fluorescence imprinted sensor was discussed in detail. The ratiometric fluorescence imprinted sensor was used to detect 4-NP in various real samples with satisfactory recoveries of 97.5–106.3%, which provided an interesting avenue for the rapid detection of pollutant with high sensitivity, high selectivity and visualization in real environment.

The elucidation of precise structure of fucoidan is essential for understanding their structure-function relationship and promoting the development of marine drugs. In this work, we firstly reported the oligosaccharide mapping of fucoidan from Holothuria floridana using a combination of hydrothermal depolymerization, hydrophilic interaction liquid chromatography (HILIC) coupled with electrospray mass spectrometry (ESI-FTMS) and high energy collision-induced dissociation (HCD-MS/MS) and 2D NMR analysis. With careful selection of fully deprotonated molecular ions of fucoidan oligosaccharides and their NaBD4 reduced alditols, HILIC-ESI-HCD-MS/MS provided structurally relevant glycosidic product ions with no sulfate loss for definitive assignment of sequence and sulfation pattern of all the oligosaccharides and their isomers from dp2 to dp7 from hydrothermal depolymerization. The oligosaccharide mapping clarified the structure of fucoidan with various oligosaccharide domains with 2,4-di-O-sulfated and 2-O sulfated fucose residues.

Di-n-butyl phthalate (DBP) as a plasticizer is widely used in food and chemical industries. It is harm to human health when it appeared in food and water. A novel near-infrared (NIR) fluorescence molecularly imprinted sensor based on CdTe quantum dots and zeolite imidazolate framework-67 was developed with a sol–gel polymerization method for rapid and sensitive determination of DBP in foodstuff rapidly (only in 1.5 min). The fluorescence imprinted sensor provided a rapid detection method for DBP in the linear response concentration range of 0.05–18.0 μM with a low detection limit of 1.6 nM. Compared with previous fluorescence imprinted sensor, it behaved faster response speed and lower detection limit for determination of DBP. The fluorescence imprinted sensor was used to detect DBP in real samples successfully with satisfied recoveries of 97.2–106.4%, suggesting a potential application in food analysis.

A highly active electrocatalyst is synthesized by employing melamine assisted metal-organic framework as the precursor. By pyrolyzing the hybrid at 350–800 °C, the precursor can be easily transferred into abundant iron and nitrogen co-doped carbon skeleton. The microbial fuel cell doped with the above treated sample at 600 °C achieves the maximum power density 2229 ± 10 mW m−2, 257% and 36.6% higher than that of activated carbon and the control sample. The total resistance decreases by 53.8% from 18.16 Ω (activated carbon) to 8.39 Ω. The reaction process is testified to be four-electron transfer. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy prove the coexistence of divalent copper and C3N4 and the incorporation of nitrogen into the network formed active sites. Thus, the ideal results make the pyrolyzed hybrid at 600 °C a promising catalyst in microbial fuel cell.

The importance of the oxidizing capacity of reactive chlorine species, and the heterogeneous reactions of atmospheric pollution gases on the surface of particles has been well established in field observation, modeling simulation and laboratory exploration. However, less is known about the reactions of reactive chlorine on mineral particles. We studied the effect of Cl2 on the heterogeneous reaction of NO2 with γ-Al2O3 by using ion chromatography and positron annihilation lifetime spectroscopy. The presence of Cl2 can promote the uptake of NO2 on γ-Al2O3 at humid conditions. The probable explanations are that Cl2 rapidly reacts with NO2 on the γ-Al2O3 surface in the presence of adsorbed water, and nitrites, as the intermediate products during the heterogeneous reaction of NO2 on mineral dust, are immediately oxidized by adsorbed Cl2. In the positron annihilation lifetime spectroscopy experiment, a porous γ-Al2O3 was demonstrated by the relatively high fourth lifetime intensity. The increase in the number of anions (onto γ-Al2O3) when the reaction time was prolonged was a direct consequence of the decrease in the o-Ps intensity and the o-Ps lifetime, which illustrated that the heterogeneous reactions might occur on the porous surface of γ-Al2O3. Our results suggest that the oxidative effect of Cl2 on the heterogeneous conversion of NO2 to nitrogen-containing particles might have a significant contribution to the fine particle growth and to the unknown sources of nitrate observed in secondary inorganic aerosols.

To extend the practical applications of collagen, alternatives to mammalian sources are needed. In this study, acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted from the cuticle of Perinereis nuntia (Savigny), and their physicochemical features and structures were examined. The yields of ASC and PSC were 3.89% and 6.74%, respectively. The glycine contents of both collagens accounted for approximately one-third of the total amino acid residues, and the sum totals of proline and hydroxyproline in ASC and PSC were 212 and 214 residues/1000 residues, respectively. However, the proline hydroxylation rates of ASC and PSC were 84.0% and 83.6%, respectively. The maximum absorption peaks of both ASC and PSC were detected at 233 nm. Zeta potential studies indicated that ASC and PSC have a net zero charge at pH 4.89 and 4.95, respectively. Fourier-transform infrared spectroscopy, circular dichroism, and X-ray diffraction confirmed the triple helical structure of the collagen. The denaturation temperatures (Td) of ASC and PSC were 36.5 °C and 33 °C, respectively. Moreover, the collagens appeared to be loose, fibrous, and porous by scanning electron microscopy. These results suggested that collagen from the cuticle of Perinereis nuntia (Savigny) has potential commercial applications in the food, nutraceutical, and pharmaceutical industries.

A novel graphene oxide (GO) immobilized quaternized polysulfone (PSF) hybrid membrane (Q-PSF/GO) was prepared via phase inversion method using GO as an additive, and triethanolamine (TEOA) as an aminated agent. TEOA, which reacted with both PSF and GO, could improve the dispersibility and compatibility of GO in membrane casting solution. The membrane exhibited highest permeability and rejection rate to bovine serum albumin (BSA) compared to bare PSF membrane and PSF/GO membrane. Expressly, when the same amount of GO was incorporated into the PSF/GO membrane and the Q-PSF/GO membrane, the Q-PSF/GO membrane showed a more satisfactory performance. The water contact angle measurement confirmed the increased hydrophilicity of the Q-PSF/GO hybrid membrane. FE-SEM images proved that the Q-PSF/GO 0.5 membrane possessed larger and more vertical finger-like pore structure in comparison with bare PSF membrane and PSF/GO membrane. Furthermore, it was proved by CLSM images that a thick and incompact layer of BSA was absorbed onto the surface of the Q-PSF/GO 0.5 membrane. However, the absorbed layer of BSA on Q-PSF/GO 0.5 membrane surface could be easily washed away compared to the bare PSF membrane.

In the present study, a dual - modified lignin (DML) adsorbent, which exhibits a high adsorption capacity for Pb2+, was prepared through the reaction of alkaline lignin with ClCH2COOH and CS2. The main objective of the present was to prepare a biomass-based adsorbent that is suitable for scavenging heavy metals from wastewater. The DML was characterized using Fourier transform-infrared Spectroscopy (FT-IR), Elemental Analysis, Conductivity titration, Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). The results show that carboxyl and ‒CSS‒ components are introduced into the DML, and the corresponding concentrations were 1.3 mmol/g and 30.5 %, yielding an adsorbent with a specific surface area of 3.13 m2/g. The rough aggregated porous structure of the DML enhances the adsorption of Pb2+. An adsorption experiments reveal that the Pb2+ adsorption by the DML is adequately represented by a pseudo - second-order kinetic equation, and these produced a maximum Pb2+ adsorption capacity of 208.3 mg/g. XPS (X-ray photoelectron spectroscopy) results demonstrates that complexation and electrostatic attraction constitute the Pb2+ adsorption mechanisms associated with the DML. The adsorbent produced in the present study is valuable for protecting water quality and the environment, and provides another avenue for the utilization of lignin.

This report depicts an environment-friendly molecularly imprinted fluorescence sensor for rapid determination of trypsin based on new near infrared (NIR) fluorescence carbon dots and metal–organic frameworks. The novel NIR fluorescence carbon dots were facilely synthesized from green plants by one-step solvothermal treatment, and the imprinted sensor was prepared by sol–gel under mild condition. The imprinted NIR fluorescence sensor was characterized by Fourier-transform infrared spectrometry, energy disperse spectroscopy, scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The results showed the introduction of zeolite imidazolate framework-8 can improve the fluorescence response sensitivity and response speed. Under optimized conditions, the fluorescence quenching of the imprinted NIR fluorescence sensor was linear relationship with the increasing trypsin concentration in the range of 0.05–9.0 ng/L with a detection limit of 8.8 pg/L. The developed imprinted fluorescence sensor can selectively recognize trypsin in 1.5 min, which was applied to rapidly and sensitively detect trypsin in serum and urine samples successfully with the recoveries of 95.3–104.1% and 97.7–105.2%, respectively. The as-prepared imprinted fluorescence sensor provides a viable and eco-friendly method for rapidly sensitive detection of trace bio-macromolecule in complex samples.

Severe haze in China has been a global concern in recent years. Most studies about the mechanism of haze formation mare only focused on the heterogeneous reactions of SO 2 and NO 2 on mineral aerosols. However, little is known about the role of molecular chlorine (Cl 2 ) in those reactions. Here, we investigated the heterogeneous uptake of Cl 2 , SO 2 and NO 2 on γ-Al 2 O 3 particles under different conditions using a quartz-based flow reactor. We found that the existence of γ-Al 2 O 3 seed aerosols significantly promotes the formation of secondary chloride, sulfate and nitrate aerosols, and Cl 2 , NO 2 and SO 2 have synergistic effects when they react on γ-Al 2 O 3 surface under humid condition. The results also shows that Cl 2 can promote the formation of secondary sulfate and nitrate aerosols on γ-Al 2 O 3 surface. Moreover, Cl 2 is much easier to react with the surface of γ-Al 2 O 3 and form secondary Cl − aerosol when comparing with NO 2 and SO 2 , suggesting that Cl 2 is of great importance in atmospheric chemistry, it has the potential to alter the surface properties (e.g., chemical composition and fraction) of mineral aerosol, enhance the production of secondary inorganic aerosols in the troposphere, and thus cause adverse effects on the climate and human health.

Flavonoids are widely distributed secondary metabolites in plants. However, far less research has been carried out on genes involved in the flavonoid biosynthetic pathways in bryophytes. Here, a novel flavanone 3-hydroxylase gene (PnF3H) was cloned from Antarctic moss Pohlia nutans. Subcellular localization revealed that PnF3H were mainly distributed to cytosol. The expression of PnF3H was rapidly induced by salt, UV-B, cold and drought stresses as well as by exogenously applied abscisic acid (ABA). Transgenic Arabidopsis plants of overexpressing PnF3H exhibited enhanced tolerance to salt and oxidative stresses. The expression levels of several stress resistance genes (i.e., AtSOS3, AtP5CS1, AtHKT1, AtCAT1 and AtAPX1) were markedly up-regulated in transgenic plants. The activities of antioxidant enzymes were increased, while the content of hydrogen peroxide was obviously decreased in PnF3H transgenic plants. Meanwhile, the expression levels of ABA-responsive genes which confer for controlling seeds germination, such as AtABI4, AtABI5, AtABI3 and AtABF3 were markedly decreased. Additionally, overexpressing PnF3H alleviated the inhibitory effects of naringenin on plant growth and changed the flavonoid components in transgenic plants. Therefore, we proposed that PnF3H was a flavanone 3-hydroxylase involving in regulating the salinity tolerance and ABA sensitivity to enable P. nutans to adapt to polar climates.

The output voltage is a key parameter to quantify the performance of piezoelectric devices, particularly for energy harvesters and sensors. Our recent work (Su et al., 2015) reported that the measured output voltage depends on the inner resistance of voltmeter used. It is contrary to the established concept that the measured results should be independent of the instruments used. Similar measurements, however, widely exist in recent published literature, which is actually not suitable to quantify the performance of piezoelectric devices. This paper proposes a universal and easy-to-use standard for the voltage measurement of piezoelectric devices. The output voltage measurements of a micro-fabricated, flexible lead zirconate titanate (PZT) mechanical energy harvester by two voltmeters with a resistance of 10 M Ω and 55 G Ω , present significantly different output voltage values ( ∼ 0.2 V vs. ∼ 2.0 V), which provide strong evidence for the unusual conclusion. A universal and easy-to-use standard of voltage measurement for piezoelectric devices requires that the inner resistance of voltmeter must be larger than a critical value in terms of effective capacitor, loading frequency and accuracy requirement of measured voltage. This standard is developed to obtain the open-circuit resistance-independent voltage. A self-developed electronic system meeting the standard requirement was built and the universality of all the findings was further validated by a commercial piezoelectric device.

DNA polymerase-β (DNA pol-β) plays a crucial role in the pathogenesis of Parkinson's disease (PD). The aim of this study was to investigate the neuroprotective effects of a DNA polymerase-β inhibitor 2',3'-dideoxycytidine (DDC) in PD models. In the in vitro studies, primary cultured neurons were challenged with 1-methyl-4-phenylpyridinium ion (MPP+). The expression of DNA pol-β was assessed using western blot. The neuroprotective effect of DNA pol-β knockdown and DNA pol-β inhibitor DDC was determined using cell viability assay and caspase-3 activity assay. We found that MPP+ induced neuronal death and the activation of caspase-3 in a dose-dependent manner. The expression of DNA pol-β increased after the neurons were exposed to MPP+. DNA pol-β siRNA or DNA pol-β inhibitor DDC attenuated neuronal death induced by MPP+. In the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD, MPTP treatment triggered behavioral deficits and nigrostriatal lesions. Pretreatment with DDC attenuated MPTP-induced behavioral deficits, dopaminergic neuronal death and striatal dopamine depletion in the MPTP mouse model. These results indicate that DNA pol-β inhibitors may present a novel promising therapeutic option for the neuroprotective treatment of PD.

Fate and toxicity of manufactured nanoparticles (NPs) in the living organisms and the environment are highly related to their transformation. In the present study, the effect of phosphate on the phytotoxicity and transformation of CeO2 NPs was investigated in an agar medium using head lettuce plants that are sensitive to Ce3+ ions. Plants were treated by CeO2 NPs with or without phosphate for 10 days. Results suggest that the treatments of P deficiency (P(-)) and CeO2 NPs (P(+)&Ce) could separately induce significant inhibition on the growth of lettuce seedlings and cause oxidative stress, but the inhibition was the most serious when the two conditions were combined (P(-)&Ce). In the absence of phosphate, more CeO2 NPs were transformed to Ce(III) in the roots and more Ce3+ ions were translocated to the shoots, which induced higher toxicity to head lettuce. Phosphates could alleviate the phytotoxic effect of CeO2 NPs through the precipitation of dissociated Ce3+ ions. Considering the wide existence of phosphate in the environment, phosphate-related transformation may be a critical factor in evaluating the toxicity and fate of many other metal-based NPs.

In this work, a novel catalyst of Fe3O4@SiO2@Yb2O3 was prepared and the degradation of thymol in reverse osmosis concentrate using ozonation was explored. The operational parameters, such as ozone dosage (8–48 mg·min− 1), initial thymol concentration (20–100 mg·L− 1), initial pH value (3–11), and catalyst Fe3O4@SiO2@Yb2O3 dosage (0.2–1.0 g), were studied focusing on the thymol degradation and COD removal. The results indicated that the increase in ozone dosage, initial pH value, and Fe3O4@SiO2@Yb2O3 dosage accelerated the thymol degradation and COD removal, while the increase in initial thymol concentration hampered the effect of ozonation. A pathway of thymol degradation by catalytic ozonation was proposed based on the intermediates detected by gas chromatography-mass spectrometer and ion chromatography. This paper can provide basic data and technical alternative for pollutant removal from reverse osmosis concentrate by ozonation.

A novel adsorbent, bioglass nanospheres (BGN), has been prepared by a facile process. The BGN were spheres with an amorphous structure and a relatively high specific surface area, as indicated by SEM, transmission electron microscopy, BET, FTIR, and XRD. This paper was aimed at evaluating the adsorption behavior of this new material for the adsorptive removal of cationic (methylene blue, neutral red) and anionic (congo red) dyes from aqueous solution. The effects of the initial dye concentration, contact time, solution pH, and temperature were investigated. The adsorption kinetics showed that the adsorption behavior followed the pseudo-second-order kinetic model. The adsorption isotherm fit well to the Langmuir model. Thermodynamic analyses showed that the adsorption was physisorption, and it was also a spontaneous and endothermic process. The BGN exhibited a good reusability after five consecutive cycles for cationic dyes. In addition, the possible adsorption mechanism was also proposed based on ...

Background and aims Recent clinical evidences show that patients with atherosclerotic cardiovascular disease can benefit from a targeting IL-1β treatment. Caspase-1 is an important factor for pyroptosis and is responsible for mature and release of interleukin (IL)-1β. Here we investigated the effect of caspase-1 inhibitor VX-765 on atherosclerosis and vascular smooth muscle cells (VSMCs) pyroptosis. Methods Human carotid artery plaques and aortas from ApoE−/− mice which were gavaged with VX-765 or vehicle while fed with western diet were examined for plaque burden using Oil Red O staining and Immunohistochemistry staining. Dedifferentiated primary cultured mice VSMCs treated with oxidized low-density lipoprotein (OxLDL) were applied to examine cell pyroptosis. Results The distribution of a-SMA and active pyroptotic indicators had a lot of overlaps near the necrotic core, at the lesion surface and in the intra-plaque hemorrhage area in human or mice plaque. In vitro studies further demonstrated that OxLDL induced VSMCs pyroptosis through activating NLRP3 inflammasome. What's more, VX-765 significantly inhibited the progression of established atheroma and the development of atherosclerosis, without substantially influence lipoprotein level in plasma. VX-765 also significantly reduced VSMCs pyroptosis and IL-1β processing induced by OxLDL. Conclusions VX-765 inhibits VSMCs pyroptosis during atherogenesis and targeting caspase-1 activity may be a potential treatment strategy for atherosclerotic diseases.

BACKGROUND: Previous studies showed that wogonin is a potential candidate for more effective treatment of neuronal and inflammatory disease and could offer neuroprotective activity in various models, but all these studies were in vitro. Our research aimed to investigate the neuroprotective effect of wogonin on focal cerebral ischemia in rats and uncover its potential mechanism. METHODS: A total of 80 male SD rats were randomly divided into a sham operation group (Sham group, 20 rats), a normal saline group (NS group, 20 rats), and a wogonin intervention group (W2W group, 20 rats), while the remaining 20 rats were kept as a substitute. The model of focal cerebral ischemia (MCAO) was established by thread embolization. The neurological deficits were evaluated by the modified neurological deficit scale (mNSS). The laser confocal technique was used to observe the diameter, density, and total area of microvessel. Lastly, the expression of transforming growth factor-β1 (TGF-β1) was detected by Western blot. RESULTS: The mNSS scores of the NS group and Wn2W group were 6.57±1.13 and 4.39±0.92 respectively, and the difference between NS group and Wn2W group was statistically significant (P

l-lysine is a basic amino acid that has been shown to exert neuroprotective effect. However, the underlying mechanism remains to be elucidated. In this study, we investigate how l-lysine exerts its neuroprotective effect in hemin-insulted mouse cortical neurons in vitro and the mouse model of intracerebral hemorrhage (ICH) in vivo. We demonstrate that l-lysine treatment promotes M2 microglial polarization and reduces inflammatory response both in vitro and in vivo, suggesting that l-lysine may play a neuroprotective role in ICH injury. Indeed, we show that l-lysine treatment reduces cortical neuronal death after hemin insult in vitro and decrease the number of degenerating neurons after ICH in vivo. l-lysine also improves the functional recovery of ICH animals in neurobehavioral tests. Consistent with the role of PTEN in regulating inflammatory response, we find that PTEN inhibition promotes M2 microglial polarization and suppresses pro-inflammatory response in mouse ICH injury, which contribute to the neuroprotective effect of l-lysine. Moreover, our results reveal that microRNA-575 directly suppressed PTEN to promote M2 microglial polarization and mediate the neuroprotective effect of l-lysine in ICH injury. Together, our results suggest that l-lysine confers neuroprotection after ICH injury through enhancing M2 microglial polarization and reducing inflammatory response, which is mediated by microRNA-575 upregulation and subsequent PTEN downregulation.

The objective of this research was to extract and prepare mycosporine-like amino acids (MAAs) and investigate the mechanism by which they act against UV-induced skin photoaging in Institute of Cancer Research (ICR ) mice. MAAs such as porphyra-334 and shinorine were extracted from Porphyra yezoensis, separated, and purified using column chromatography with SA-2 cation exchange resin. The effects of MAAs on the activity of endogenous antioxidant enzymes, namely total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA) were analyzed in mouse skin tissue. Pathological changes of skin tissue caused by ultraviolet radiation and the arrangement of collagen were observed by Hematoxylin-Eosin (HE) staining and scanning electron microscopy (SEM). Interleukin 1&beta, (IL-1&beta, ), IL-6, and IL-10 were detected using the quantitative real-time reverse transcription-polymerase chain reaction (qPCR) and Enzyme Linked Immunosorbent Assay (ELISA). The concentration and expression of these proinflammatory cytokines was associated with the presence of nuclear factor (NF)-&kappa, B. The results show that MAA compounds from Porphyra yezoensis could suppress UV-induced photoaging of skin by inhibiting the reduction of endogenous antioxidant enzymes. Compared to the control group, the concentrations of SOD, GSH-Px, and CAT increased significantly in skin tissue homogenate following the external administration of MAAs (p &lt, 0.05, p &lt, 0.01), while the content of MDA decreased significantly (p &lt, 0.05). Meanwhile, the administration of MAAs was associated with down-regulations in the concentration and mRNA expression of NF-&kappa, B, IL-1&beta, IL-6, and IL-10. The results suggest that MAAs could protect skin from photodamage by increasing antioxidant enzyme activities and inhibiting inflammation.

7,8-Dihydroxyflavone (7,8-DHF) is thought to be a promising therapeutic agent for various neurodegenerative diseases. The major purpose of this study was to investigate the neuroprotective effects of 7,8-DHF on the rotenone-induced motor deficit of Parkinson’s disease. Nine-month-old rats were treated with rotenone (2 mg/kg/day, i.h.) for 5 weeks to establish the animal model of Parkinson’s disease (PD), and 7,8-DHF (5 mg/kg, i.p.) was administrated daily throughout the whole period of rotenone injection. Five weeks later, an open field test was used to assess the motor ability of the animals. TH immunostaining was performed to evaluate rotenone-induced neurotoxicity on substantia nigra (SN) dopaminergic neurons and the DA terminals in the striatum. Western blot analyses were used to examine the expressions of TH, BDNF/TrkB signaling cascades, phospho-α-synuclein (Ser129), α-synuclein, and phospho-tau (Ser396) in SN. The results revealed that treatment with 7,8-DHF improved PD model’s behavioral performance and reduced dopaminergic neuron loss in the SN and striatum, associated with the activation of TrkB receptors and its signaling cascades, and reduced p-MAPK, p-α-synuclein, and p-tau. Collectively, these results indicated that 7,8-DHF displayed prominent neuroprotective properties, providing a promising therapeutic strategy for PD treatment.

Using a many spin micromagnetic simulation tool that directly integrates the Landau-Lifshitz equation, we demonstrate that by applying an r.f. pulse, generally referred to as a Pi pulse, it is possible to near-perfectly reverse the direction of the magnetization in a ferromagnet, provided that the sample is sufficiently small and the angular dependence of the precession frequency is continuously matched using an appropriately “chirped” r.f. pulse of the proper length. Simulations are carried out for “prolate” uniaxially symmetric cylindrical samples in the presence of dipole and exchange interactions. Such reversals can be performed in the presence of a static external magnetic field or, importantly, at zero field under the sample’s own internal demagnetization field. However, the ability to perform near-perfect Pi or two-Pi rotations is lost for samples above certain dimensions for which additional internal degrees of freedom are excited, particularly at higher static fields. In such larger samples the magnetization may still be reversed by utilizing damping, provided it can be rotated past a critical angle.

In order to improve the antibacterial ability and weather resistance of acrylic emulsion, a novel kind of antibacterial fluorinated acrylic emulsion was prepared by emulsion polymerization with methacrylatoethyl trimethyl ammonium chloride (MTAC) and hexafluorobutyl methacrylate (HFMA) as functional monomers. Based on various characterizations, results for the emulsion and its coating indicated that the modifying monomers were bonded into the new emulsion, and enabled it to perform good weatherability and antibacterial activity. Through 240 h accelerated aging test, the color difference (ΔE) and rate of loss of gloss (ΔG) of the new coating were 12.44 and 20.18% respectively, much lower than 17.06 and 52.62% of the unmodified coating. After incubated at 37 °C for 18 h, the number of colonies on the surface of the medium doped with the new emulsion was only 24, while those numbers in the control groups were all as high as tens of thousands. This study provided new idea for the dual modification of antibacterial property and weather resistance of acrylic emulsion.

In order to better disperse zeolitic imidazolate framework-8 (ZIF-8) in aqueous solution for thin film nanocomposite (TFN) membrane fabrication, hydrophilic ZIF-8 was prepared by polydopamine modification. After the interfacial polymerization (IP) reaction, PDA-ZIF-8 nanoparticles were evenly entrapped in the polyamide (PA) matrix. The as-obtained PA layer demonstrated better hydrophilicity, higher surface roughness, and less cross-linking degree. Therefore, the water permeability increased by 66 % compared to the thin film composite (TFC) membrane without nanofillers. Moreover, due to the improved compatibility of PDA-ZIF-8 as well as the stronger negatively charged membrane surface, the retention of SO42− was slightly enhanced, and the retention of rhodamine B was well maintained. The hydrophilic modification of ZIF-8 by PDA was a facile method to improve its compatibility with the PA polymer, and the resultant TFN membrane demonstrated elevated water permeability without compromising its selectivity.