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In this study, Nb modification was applied to promote the performance of selective catalytic reduction (SCR) of NOx and NH4HSO4 (ABS) resistance of pure silica molecular sieve KIT-6-supported copper nanoporous catalysts. Experimental results revealed that the optimal Cu5–NK sample possessed above 80% deNOx efficiency with good N2 selectivity in the temperature range of 260–400 °C and ABS deposition only reduced the SCR efficiency of the Cu5–NK sample by 20% at 320 °C. Characterization results indicated that Nb modification would induce formation of strong interactions with Cu, which enlarged pore size, amplified dispersion of active Cu species, and enhanced redox ability and surface acidity. Importantly, the enlarged pore size could weaken the thermal stability of ABS and promote its decomposition, while more active Cu sites retained by strong Cu–Nb interactions could participate in the SCR reaction and easily consume NH4+ from the deposited ABS on the catalyst. These were the main reasons for promoting SCR performances and ABS resistance of Cu-KIT-6 nanoporous catalysts by Nb modification. Such findings could pave a way for the development of highly efficient SCR catalysts with good ABS resistance for real application. [ABSTRACT FROM AUTHOR]

A mitochondria-targeted ratiometric fluorescent probe (Mito-Zn) was first designed and synthesized with dual emissions both located in the near-infrared region, for Zn2+ detection with high sensitivity and selectivity. By using the developed Mito-Zn, a high level of Zn2+ in the depressed mouse brain was discovered for the first time. [ABSTRACT FROM AUTHOR]

Quasi-bilayered actuators composed of Fe3O4-decorated graphene oxide and polyvinylidene fluoride have been fabricated in a magnetic field. The actuators could stably respond to multiple stimuli including infrared light, acetone vapour and a magnetic field. The actuator is also patternable because of the magnetism-induced spatial distribution of fillers in the matrix. [ABSTRACT FROM AUTHOR]

As a vital organelle in eukaryotic cells, the Golgi apparatus is responsible for processing and transporting proteins in cells. Precisely monitoring the status of the Golgi apparatus with targeted fluorescence imaging technology is of enormous importance but remains a dramatically challenging task. In this study, we demonstrate the construction of the first Golgi apparatus-targeted near-infrared (NIR) fluorescent nanoprobe, termed Golgi-Pdots. As a starting point of our investigation, hydrophobic carbon nanodots (CNDs) with bright NIR fluorescence at 674 nm (fluorescence quantum yield: 12.18%), a narrow emission band of 23 nm, and excellent stability were easily prepared from Magnolia Denudata flowers using an ultrasonic method. Incorporating the CNDs into a polymer matrix modified with Golgi-targeting molecules allowed for the production of the water-soluble Golgi-Pdots, which showed high colloidal stability and similar optical properties compared with pristine CNDs. Further studies revealed that the Golgi-Pdots showed good biocompatibility and Golgi apparatus-targeting capability. Based on these fascinating merits, utilizing Golgi-Pdots for the long-term tracking of the Golgi apparatus inside live cells was immensely successful. [ABSTRACT FROM AUTHOR]

β-1,4 Galactosyltransferase V (β-1,4-GalT V) belongs to the β-1,4 galactosyltransferase family, which modifies proteins and plays a vital role in biological function. Our previous study revealed that β-1,4-GalT V was expressed in the cortex and hippocampus and participated in the recovery of spatial learning and memory in rats with traumatic brain injury. However, the expression of β-1,4-GalT V in microglia, resident immune cells in the central nervous system, and its impact on microglia in resting and lipopolysaccharide-triggered activated stages are elusive. In this study, we clarified that β-1,4-GalT V expresses in microglia, and it regulates microglial migration, proliferation, and release of the inflammatory factors. We also observed that β-1,4-GalT V affects the expression level of tumor necrosis factor receptor (TNFR)2 instead of TNFR1. These results strongly support the fact that β-1,4-GalT V is involved in microglial function. [ABSTRACT FROM AUTHOR]

To understand the binding affinities between HCl and N,N-dimethylamine derivatives in halogen-containing solvents, and to explore the contribution of chemical substitution toward the photoinduced electron transfer (PET) process, we have designed and prepared a series of perylene tetracarboxylic diimides (PDIs) functionalized with various N,N-dimethylamine groups. All five new molecules are well soluble in chloroform, an important requirement for gamma radiation detection, and sensitive to the concentration of HCl in such a non-polar solvent. The weak fluorescence of the pristine PDIs is due to the intramolecular PET effect. After binding to HCl, the PDIs are highly fluorescent, because the PET effect is suppressed. This phenomenon is well characterized by UV-Vis spectra, fluorescence spectra, and HCl titration experiments. Their fluorescence mechanism and detection ability have been carefully studied, and their effects on the detection of gamma radiation dosage are analyzed by fitting calculations. The aromatic amine provides the lowest fluorescent background, probably because of the most efficient PET. In the cases of alkylamines, shorter chains lead to a narrower detection range, while longer chains show inefficient PET. The optimal detection limit of HCl is as low as 0.38 μM, the linear detection range for HCl is 0.38–40, and the projected linear gamma radiation detection range is 0–5 Gy, which is the widest linear detection range in comparison with the literature. [ABSTRACT FROM AUTHOR]

In this study, an anaerobically digested effluent from kitchen waste with high concentrations of chemical oxygen demand (COD) and ammonia nitrogen was treated using combined processes of anaerobic digestion (AD), complete nitritation (CN), and anaerobic ammonium oxidation (ANAMMOX). The COD and nitrogen removal efficiency of each treatment unit were investigated. The feasibility of using the final treatment effluent to dilute the original wastewater was also discussed. Findings showed that as a pretreatment step, AD resulted in the decline in biodegradability and increase in NH4+- N concentration. CN was successfully and stably achieved for 106 days with an average nitritation rate of 95% by maintaining the dissolved oxygen at 2–3 mg/L and hydraulic retention time of 24 hr under 30 ± 1°C. High NH4+- N and NO2-- N. removal efficiencies of over 88% and 96% were attained in the following ANAMMOX reactor. The reflux of ANAMMOX‐treated effluent for the dilution of raw wastewater or an influent of CN and ANAMMOX ensured the stable operation of the combined system. Practitioner points: Anaerobic digestion effluent of kitchen waste had low COD/NH4+-N ratio and poor biodegradability.Stable and efficient nitritation was realized by controlling DO, HRT and TEMP.High NH4+-N and NO2--N removal efficiency were obtained by ANAMMOX process.Average nitrogen removal rate of 0.94 kg N/m3/day were obtained by ANAMMOX.Reflux dilution with the effluent guaranteed the system's successful operation. [ABSTRACT FROM AUTHOR]

Steroid estrogens (SEs), especially 17β-estradiol (E2), can be a serious threat to the health of organisms. The removal of E2 from the natural environment is mainly carried out by microbial degradation partly mediated by biochar, which contains quinone structures. In this study, reed straw biochar samples made at four different heat treatment temperatures (HTTs) were used to mediate E2 microbial degradation by Shewanella oneidensis MR-1. The removal efficiency of E2 (95%) was highest in the presence of HTT – 500 °C biochar under anaerobic conditions after 120 h of microbial degradation. The effect of biochar on promoting microbial degradation was far more superior under anaerobic conditions than under aerobic conditions. The redox-activity and types of surface functional groups of biochar reveal that biochar can accept electrons generated by microorganisms in a timely manner. This mechanism promotes the metabolic process of cells and microbial degradation of E2 (exponential increase). Biochar particles rather than biochar-derived water-soluble organic compounds are responsible for this stimulating effect. These results highlight the impact that biochar has on microbial degradation of trace pollutants in a natural environment. [ABSTRACT FROM AUTHOR]

Electron shuttles extensively exist in various environments. Some kinds of organic substances can be applied by microorganisms to produce electrons, and then the electrons can be transferred to other substances or microorganisms through electron shuttles, resulting in coexistence and interaction of diverse species of microbes. In this review, the functional mechanisms of extracellular electron transfer mediated by different electron shuttles are described. And different subtypes as well as the application of electron shuttles in microbial degradation of pollutants, microbial electricity, and the promotion of energy generation are also discussed. Summary results show that extracellular electron transfer is based on the electrogenesis microorganism with the structure of cytochromes or pili. Materials were usually used in long-distance electron transfer because of their widespread presence and abundance. Therefore, the review is beneficial to perceive the pathways of extracellular electron transfer mediated by electron shuttles and explore the contribution of different electron shuttles in extracellular electron transfer. [ABSTRACT FROM AUTHOR]

2-Allylphenol (2-AP) is an effective fungicide against a number of plant pathogens, which can be metabolized and bio-transformed to four chemical compounds by Rhizoctonia cerealis . To determine if its degradation affects antifungal activity, two major metabolites derived from 2-AP including 2-(2-hydroxypropyl) phenol and 2-(3-hydroxypropyl) phenol were synthesized. Inhibition of mycelial growth of several plant pathogens by the metabolites was evaluated, and structures of two metabolites were determined by hydrogen nuclear magnetic resonance ( 1 H NMR). Among these metabolites, only 2-(2-hydroxypropyl) phenol inhibited test pathogens effectively. EC 50 values of 2-(2-hydroxypropyl) phenol for inhibition of mycelial growth of R. cerealis , Pythium aphanidermatum , Valsa mali and Botrytis cinerea ranged from 1.0 to 23.5 μg/ml, which were lower than the parental fungicide 2-AP that ranged from 8.2 to 48.8 μg/ml. Hyphae of R. cerealis and P. aphanidermatum treated with 2-(2-hydroxypropyl) phenol were twisted. Newly developed hyphae were slender, twisted and swollen on the tip, while old hyphae were hollow and ruptured. This is the first report indicating the formation of 2-(2-hydroxypropyl) phenol may have contributed to toxicity of 2-allylphenol in control of plant pathogens. [ABSTRACT FROM AUTHOR]

The wavelength dependence of laser induced surface damage in fused silica is experimentally studied in a wide wavelength range from 260 to 1550 nm. An optical parametric oscillator system is used to provide the tunable laser pulses with a duration of 5 ns. In the experiments, the exit surface of the silica slice is observed to be damaged prior to the entrance surface. The damage threshold decreases gradually as the wavelength decreases from 1550 to 324 nm and drops suddenly at 324 nm, which corresponds to a half of 7.66 eV. This wavelength dependence can be explained by a defect assisted multiphoton absorption mechanism. By fitting the experimental data with a power law equation, the damage threshold is found to be proportional to the 3.47-th power of wavelength in the range of 325–685 nm and 1.1-th power of wavelength in the range of 260–1550 nm. [ABSTRACT FROM AUTHOR]