Construction and regulation of high active sites in montmorillonite composite catalyst for the removal of ofloxacin via persulfate activation.

In this study, ionic liquids (ILs) were used as organic modifiers by introducing montmorillonite nanolayers containing potential C and N active sites between the montmorillonite nanolayers. Organically modified montmorillonite (ILs-Mt-p) was further prepared by high-temperature pyrolysis under N2 and used for the removal of ofloxacin (OFL) by activated peroxymonosulfate (PMS). Combined with XPS and other characterization analyses, it was found that the catalyst materials prepared from different organic modifiers had similar surface functional groups and graphitized structures, but contained differences in the types and numbers of C and N active sites. The catalyst (3CPC-Mt-p) obtained after pyrolysis of montmorillonite modified with cetylpyridinium chloride (CPC) had optimal catalytic performance, in which graphitic C, graphitic N, and carbonyl group (C[bond, double bond]O) could synergistically promote the activation of PMS by electron transfer, and 77.3 % of OFL could be removed within 60 min. The effects of OFL concentration, initial pH, and anions on the effects of OFL removal by the 3CPC-Mt-p/PMS system were further investigated. Satisfactory degradation results were obtained over a wide pH range. Cl- promoted the system to degrade OFL, while the presence of SO42-, H2PO4- and HA showed some inhibition, but overall the 3CPC-Mt-p catalysts had a strong anti-interference ability, showing good application prospects. The quenching experiments and EPR tests showed that O2-- and 1O2 in the 3CPC-Mt-p/PMS system were the main reactive oxygen species for the degradation of OFL, and •OH was also involved in the reaction. This study provides ideas for the construction and modulation of active sites in mineral materials such as montmorillonite and broadens the application of montmorillonite composite catalysts in advanced oxidation processes for the treatment of antibiotic wastewater.

Metal-Based Electrocatalysts for Selective Electrochemical Nitrogen Reduction to Ammonia.

Ammonia (NH3) plays a significant role in the manufacture of fertilizers, nitrogen-containing chemical production, and hydrogen storage. The electrochemical nitrogen reduction reaction (e-NRR) is an attractive prospect for achieving clean and sustainable NH3 production, under mild conditions driven by renewable energy. The sluggish cleavage of N≡N bonds and poor selectivity of e-NRR are the primary challenges for e-NRR, over the competitive hydrogen evolution reaction (HER). The rational design of e-NRR electrocatalysts is of vital significance and should be based on a thorough understanding of the structure-activity relationship and mechanism. Among the various explored e-NRR catalysts, metal-based electrocatalysts have drawn increasing attention due to their remarkable performances. This review highlighted the recent progress and developments in metal-based electrocatalysts for e-NRR. Different kinds of metal-based electrocatalysts used in NH3 synthesis (including noble-metal-based catalysts, non-noble-metal-based catalysts, and metal compound catalysts) were introduced. The theoretical screening and the experimental practice of rational metal-based electrocatalyst design with different strategies were systematically summarized. Additionally, the structure-function relationship to improve the NH3 yield was evaluated. Finally, current challenges and perspectives of this burgeoning area were provided. The objective of this review is to provide a comprehensive understanding of metal-based e-NRR electrocatalysts with a focus on enhancing their efficiency in the future.

Kelp-derived N-doped biochar activated peroxymonosulfate for ofloxacin degradation.

N-doped carbon materials have been proven to be effective catalysts for activating peroxymonosulfate (PMS). Marine algae biomass is rich in nitrogenous substances , which can reduce the cost of N-doping process and can obtain excellent N-doped catalysts cheaply and easily. In this study, kelp biomass was selected to prepare N-doped kelp biochar (KB) materials. The high defect degree, high specific surface area, and participation of graphite N make KB have excellent catalytic degradation ability. The KB degraded 40 mg/L ofloxacin (OFL) close to 100% within 60 min, applied with PMS. Through quenching experiments and electron paramagnetic resonance spectroscopy, the degradation process dominated by non-radical pathways was determined. At the same time, O2·- and 1O2 were closely related, and a significant impact of quenching O2·- on the reaction was observed. The non-radical approach made the system excellent performance over a wide pH range and in the presence of multiple anions. The experiments of reusability confirmed the stability of the material. Its catalytic performance was restored after low-temperature pyrolysis. This research supports the use of endogenous nitrogen in biomass. It provides more options for advanced oxidation process application and marine resource development.

Steroidal glycoalkaloids from Solanum lyratum inhibit the pro-angiogenic activity of A549-derived exosomes.

In this study, seven previously undescribed steroidal glycoalkaloids, compounds 1-7, were isolated from Solanum lyratum, along with two known ones (8 and 9). Comprehensive spectroscopy techniques were used to determine their structures. Although 1-8 only showed a weak inhibitory effect on the proliferation of the tumor-derived vascular endothelial cells, however, in a former study we found both total steroidal glycoalkaloids from Solanum lyratum (TSGS) and 9 significantly inhibited tumor angiogenesis and its mechanism was linked to its ability to interfere with cell membrane lipid rafts. Lipid rafts are closely related to the functions of tumor-derived exosomes, a vital factor in cancer progression. Thus, we investigated the impacts of TSGS and 9 on the functions of A549-derived exosomes. Our results indicated that A549-derived exosomes can significantly enhance the angiogenesis abilities of human umbilical vein endothelial cells, whereas the intervention of TSGS or 9 significantly inhibited this activity of A549-derived exosomes. These findings suggest that TSGS and 9 exert anti-tumor angiogenesis by inhibiting the pro-angiogenic activity of A549-derived exosomes.

An-te-xiao capsule inhibits tumor growth in non-small cell lung cancer by targeting angiogenesis.

An-te-xiao capsule consists of total alkaloids from the dried whole plantof Solanum lyratum, and showed antitumor effects in our previous study. However, its inhibitory effect on multiple non-small cell lung cancer (NSCLC) cell lines and the underlying mechanisms have not been elucidated clearly. This study sought to investigate the inhibitory effects of An-te-xiao capsule on three main types of NSCLC cell lines (A549, NCI-H460, and NCI-H520) in vitro and in vivo and the underlying mechanisms of action including its potential anti-angiogenesis effects. An-te-xiao capsule showed no acute oral toxicity in mice, and significantly prolonged survival time in a mouse model of Lewis tumor xenograft. The inhibition of A549, NCI-H460, and NCI-H520 cells by An-te-xiao capsule was reflected in its effects on tumor growth, histopathological changes, tumor microvessel density (MVD), cell cycle regulatory proteins, and cell apoptosis. In vitro, An-te-xiao capsule repressed migration, invasion, and tube formation of tumor-derived vascular endothelial cells (Td-ECs), which were obtained using a co-culture system, in the presence or absence of vascular endothelial growth factor (VEGF) at safe concentrations selected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Moreover, An-te-xiao capsule inhibited the secretion of VEGF by A549 cells in the co-culture system and suppressed the phosphorylation of VEGF receptor 2 (VEGFR2). Taken together, An-te-xiao capsule has potential for treating NSCLC.

Biotic and Abiotic Stresses Activate Different Ca2+ Permeable Channels in Arabidopsis.

To survive, plants must respond rapidly and effectively to various stress factors, including biotic and abiotic stresses. Salinity stress triggers the increase of cytosolic free Ca2+ concentration ([Ca2+]i) via Ca2+ influx across the plasma membrane, as well as bacterial flg22 and plant endogenous peptide Pep1. However, the interaction between abiotic stress-induced [Ca2+]i increases and biotic stress-induced [Ca2+]i increases is still not clear. Employing an aequorin-based Ca2+ imaging assay, in this work, we investigated the [Ca2+]i changes in response to flg22, Pep1, and NaCl treatments in Arabidopsis thaliana. We observed an additive effect on the [Ca2+]i increase which induced by flg22, Pep1, and NaCl. Our results indicate that biotic and abiotic stresses may activate different Ca2+ permeable channels. Further, calcium signal induced by biotic and abiotic stresses was independent in terms of spatial and temporal patterning.

Treatments for the Fifth Metacarpal Neck Fractures: A Network Meta-analysis of Randomized Controlled Trials.

The fifth metacarpal neck fractures (commonly termed boxer's fractures) are the most common type of metacarpal fractures. Many types of treatments are available in clinical practice, some of which have already been compared with other treatments by various researchers. However, a comprehensive treatment comparison is lacking. We estimated the comparative efficacy of different interventions for total complications, through a network meta-analysis of randomized controlled trials. We conducted a systematic search of the literature through October 2015. The outcome measurements were the total complications. We used a Bayesian network meta-analysis to combine direct and indirect evidence and to estimate the relative effects of treatment. We identified 6 RCTs registering a total of 288 patients who were eligible for our network meta-analysis. The literature's quality is relatively high. The median Structured Effectiveness for Quality Evaluation of Study score for the included trials was 33.8. The overall methodological quality was high. Of the 6 studies, all were 2-arm controlled trials comparing active intervention. Among the 4 treatments--conservative treatment (CT), antegrade intramedullary nailing (AIMN), transverse pinning (TP) with K-wires, and plate fixation (PF)--CT had the best rankings (ie, lowest risk of total complications), followed by PF, AIMN, and TP (ie, highest risk of total complications). Furthermore, we also presented the results using surface under the cumulative ranking curve. The surface under the cumulative ranking curve probabilities were 94.1%, 52.9%, 37.3%, and 15.7% for CT, PF, AIMN, and TP, respectively. In conclusion, current evidence suggested that conservative treatment is the optimum treatment for the fifth metacarpal neck fractures because of reduced total complication rates. Moreover, the TP with K-wires is the worst option with highly total complication rates. PF and AIMN therapy should be considered as the first-line choices. Larger and higher-quality randomized controlled trials are required to confirm these conclusions and better inform clinical decision-making.

[Combination process of microwave desorption-catalytic combustion for toluene treatment].

Using activated carbon as adsorbent, toluene waste gas was treated by adsorption process. After the adsorption process was completed, the adsorbent was desorbed by microwave irradiation; then Cu-Mn oxide composite catalysts were prepared by impregnation and the desorbed toluene gas was treated by catalytic combustion so as to completely purify the pollutant. The concentration of toluene was measured by gas chromatography (GC). The results indicated that it is feasible to add air to provide oxygen to the desorbed gas after the completion of the desorption process, in order to achieve the catalytic combustion; the ratio of desorbed gas and air was 1 : 1 (volume ratio), and the corresponding catalytic space velocity was 2.67 s(-1). Desorption temperature could affect the concentration of toluene in the desorption gas thereby affecting the catalytic combustion efficiency; the results indicated that 400 degrees C was an appropriate temperature for desorbing the activated carbon. When the catalytic combustion was kept at 300 degrees C, the final toluene treatment efficiency was higher than 90%, which was higher than 95% during the most time of the treatment process.

Green synthesis of silver nanoparticles using 4-acetamido-TEMPO-oxidized curdlan.

A facile, simple, and eco-friendly method using 4-acetamido-2,2,6,6-tetramethypiperidine-1-oxyl radical-oxidized curdlan (Oc) as both reducing and stabilizing agents was developed for the fabrication of silver nanoparticles (AgNPs) from silver nitrate (AgNO3). The structure, morphology, and particle size of the as-prepared AgNPs were investigated by ultraviolet-visible spectroscopy, transmission electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, and dynamic laser light scattering. The well-dispersed AgNPs were sphere like with a mean diameter of 15 nm. Their formation was dependent on reaction duration, reaction temperature, Oc concentration, and AgNO3 concentration. Fourier transform-infrared and Raman spectra demonstrated that the as-prepared AgNPs can readily bind covalently with the carboxylate groups of Oc through the strong monodentate interaction in the reaction medium.

[Comparison of toluene adsorption with two kinds of modified activated carbon].

Granular activated carbon (GAC) was modified by microwave irradiation and electrical heating. The characters and toluene adsorption capacity of modified GAC were studied. The results showed that for microwave heating, with the temperature increasing, the activated carbon's ability of toluene adsorption and content of the surface basic functional group were increased, specific surface area was decreased. After heated at 850 degrees C, GAC had the highest ability for toluene adsorption, at 650 degrees C and 450 degrees C, the ability for toluene adsorption of GAC were similar. For the electrical heating, the same results were obtained. But the GAC modified with electrical heating had lower capacity of toluene adsorption than microwave modified GAC. The SEM photos showed that thermal modification made the porous structure of modified GAC smoother than original GAC, but the structure of GAC shrink at high temperature. Finally, all the experimental data and SEM photos were analyzed; it indicated that due to the difference of heating mechanism and heat transmission direction, the modified GAC have different characters.

[Influence factors of treating waste gas containing benzene and toluene with fungi-biofilter].

Used a two-stage bench-scale temperature adjustable biofilter, biological treatment of medium and high concentration waste benzene and toluene vapor was investigated. The inlet vapor concentration (c(i)) was 0.9 - 5.0 g/m3. The results show that the biofilter can obtained good performance at 30 - 40 degrees C, and at 32.8 degrees C for benzene and toluene, the maximum elimination capacity (EC) of 136 g/(m3 x h) and 150 g/(m3 x h) is obtained at an inlet loading of 673.5 g/(m3 x h) and 665.0 g/(m3 x h), respectively. High media moisture is adverse to the biofilter performance. The optimum moisture for the biofilter is about 45% and the biofilter can obtain good performance at the moisture ranging from 40% to 50%. With the biofilter operation, pressure drop is increasing from 18 Pa to 39 Pa and leachate is changing from colorless to yellow, and these phenomena show that bioaccumulation is existent.