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For better use of solar energy, the development of efficient broadband photocatalyst has attracted extraordinary attention. In this study, a ternary composite consisting of Sr2LaF7:Yb3+,Er3+ upconversion (UC) nanocrystals and Bi nanoparticles loaded BiOBr nanosheets with oxygen vacancies (OVs, SLFBB) was designed and synthesized by multistep solvent-thermal method. Mechanisms of in-situ formation of Bi nanoparticles and OVs in BiOBr/Sr2LaF7:Yb3+,Er3+ composites (SFLB) are clarified. The Bi metal and OVs enhanced the light-harvesting capacity in the region of visible-near-infrared (Vis-NIR), and promoted the separation of electron–hole (e−/h+) pairs. Furthermore, the surface plasmon resonance (SPR) effect of Bi metal can improve the energy transfer from Sr2LaF7:Yb3+,Er3+ to BiOBr via nonradiative energy transfer process, resulting in enhancing the light utilization from upconverting NIR into Vis light. Due to the synergistic effects of UC function, SPR and OVs, the SFLBB exhibited obviously enhanced photocatalytic ability for the degradation of BPA with a rate of 8.9 × 10−3 min−1, which is about 2.78 times higher than 3.2 × 10−3 min−1 of BiOBr (BOB) under UV–Vis-NIR light irradiation. This work provides a novel strategy for the project of high-efficiency Bismuth-based broadband photocatalysts, which is helpful to further understand the mechanism of enhanced photocatalysis by UC function and plasmonic effect.

Nitrogen-doped graphite-encapsulated cobalt nanoparticles (Co@G NPs) were fabricated via a one-step arc-discharge method. The core/shell nanostructure and surface functionality were tailored by changing the ammonia content in the working gas mixture. Specifically, the average core diameter changed from 5 to 23 nm, average graphite shell thickness from 1.5 to 3.5 nm as the NH3 ratio increased from 0% to 20%. All these arc products exhibited better microwave absorption properties than the pristine Co micro powders. Co@G NPs prepared with 5% of NH3 presented 1.5 at.% of surface doping nitrogen, showing the optimal reflection loss (RL) value of −37.70 dB at the thickness of 5 mm. For the products prepared with 12.5% of NH3, wide absorption bandwidths of 5.60 GHz (RL

Photocatalytic behavior and upconversion (UC) luminescence of rare earth (RE) ions are two opposite photophysical processes; however, improving the ultimate light conversion efficiency, light absorption enhancement and suppression of excited state electronic recombination is identically crucial to both. In this work, we report an oxygen vacancy engineering strategy for BiOCl:Yb3+–Er3+ nanosheets by polypyrrole (PPY) in situ modification that connects the two photophysical processes, which may become an important aspect of expanding the application of near-infrared (NIR) light for photocatalysis. It is indicated that compared with unmodified samples, NIR and the visible light degradation of the rhodamine B (RhB) efficiencies of PPY-modified nanosheets were increased by 7.66 and 8.93 times, respectively; moreover, the UC emission of Er3+ ions under 980 nm excitation increased by 59 times. Experimental and DFT calculation results show that the oxygen vacancies (OVs) induced by PPY modification not only extend the absorption to the NIR regions by the construction of intermediate energy bands, but also promote the separation of photogenerated carriers of BiOCl nanosheets by enhancing the internal electric field (IEF). We showed that the energy ladder effect of the 4f–4f transitions of RE ion helps the intermediate energy bands to utilize NIR light to achieve more efficient photocatalysis; the extended decay rates of RE ion under the enhanced IEF are responsible for the much stronger UC emission at the same time. The results of this work exploring high-efficiency photocatalytic materials with NIR response is of great significance to further improve solar energy utilization efficiency and promote the development and application of photocatalytic technology.

Highly concentrated amino group-modified biochars derived from twelve biomass residuals are achieved using a two-step radio-frequency Ar/NH3 plasma. The dependence of amino number, N bonding states, surface defects on the pretreatment time of Ar plasma, post-treatment power, duration and gas ratio are well established. For bamboo-biochar, the amino number and N content reach the maximum (8.04 × 1016/mg of biochar, 8.84 at.%) at 8.0% NH3 in NH3/Ar, presenting a highly consistent variation tendency with the emission intensity of NH radical. Notably, micropores can be created in matrix by the processing of plasma in moderate conditions, i.e., a given pretreatment time (e.g., 12.5 min), specific gas ratios of post-treatment (≥50% of NH3) at high RF power (e.g., 240 W) and proper duration (≤15.0 min). The uptake capacities of Pb(II) (123.1 mg g−1), Cu(II) (98.5 mg g−1) and Cd(II) (61.2 mg g−1) on aminated biochars are 5.42, 5.38 and 7.56 times higher than those on raw biochars. This study shows attractive prospects for the fundamental research in powder modification as well as potentials in environmental management.

Many studies have confirmed that exhaustive exercise has adverse effects on the heart by generating reactive oxygen species (ROS). S100A1 calcium-binding protein A1 (S100A1) is a regulator of myocardial contractility and a protector against myocardial injury. However, few studies have investigated the role of S100A1 in the regulation of myocardial injury induced by exhaustive exercise. In the present study, we suggested that exhaustive exercise led to increased ROS, downregulation of S100a1, and myocardial injury. Downregulation of S100a1 promoted exhaustive exercise-induced myocardial injury and overexpression of S100A1 reversed oxidative stress-induced cardiomyocyte injury, indicating S100A1 is a protective factor against myocardial injury caused by exhaustive exercise. We also found that downregulation of S100A1 promoted damage to critical proteins of the mitochondria by inhibiting the expression of Ant1, Pgc1a, and Tfam under exhaustive exercise. Our study indicated S100A1 as a potential prognostic biomarker or therapeutic target to improve the myocardial damage induced by exhaustive exercise and provided new insights into the molecular mechanisms underlying the myocardial injury effect of exhaustive exercise.

‘of a near-infrared (NIR) fluorescent probe,’ Palladium ions show many negative effects on human health via the interference with the tissue macromolecules and the function of enzymes. In this paper, a novel benzothiazolium-thioxanthene hemicyanine dye BTX-OH has been synthesized for the design of a near-infrared (NIR) fluorescent probe. The dye BTX-OH in aqueous solution showed its absorption and fluorescence emission maxima in the NIR region at 750 nm and 795 nm, respectively. The application of the dye in designing a Pd2+-selective fluorescence probe BTX-A based on a “protect-deprotect” strategy by using an allyl carbonate group as the specific Pd2+-responding site has been demonstrated. The probe BTX-A exhibited high selectivity and sensitivity for detecting Pd2+ ions. In the presence of Pd2+ ions, the probe showed an enhanced fluorescence response and accumulated specifically in lysosomes in living-cell imaging.

The reasonable cellular redox equilibrium mediated by reactive oxygen species/reactive nitrogen species and antioxidants are pivotal importance for maintaining a variety of physiological processes, and disrupted redox equilibrium may derange the cellular components and eventually may lead to cell death, irreversible tissue destruction, and various diseases. In this paper, we develop a phenylseleno-functionalized reversible fluorescent probe Fluo-Se for monitoring the hypochlorous acid/cysteine redox couple in living cells. The advantages of the probe included: a) the synthetic procedure of the probe is very simple by one step reaction; b) the probe shows high sensitivity for HOCl and cysteine (the detection limit is 1.1 nM and 3.0 nM, respectively); c) the probe exhibits high reversibility to the hypochlorous acid/cysteine redox couple both in solutions and in the living cell by taking advantage of the Se atom-led excellent reversible conversions between Fluo-Se and its oxidized product. We think that Fluo-Se should be very useful for gauging the cellular redox status mediated by the hypochlorous acid/cysteine couple.

Lanthanide-doped BiOCl have attracted extraordinary attention due to their fascinating luminescence properties. Rational structural design is indispensable for exploring the potential application of lanthanide-doped BiOCl. In this work, BiOCl:Eu3+ microcrystals with multiform morphologies were prepared by a simple solvothermal method. The thickness and morphologies of the samples could be tuned just by changing bismuth source and reaction solvent, include 1D nanorods (NRs), 2D nanosheets (NPs), and 3D hierarchical porous structures (HPs). Under the excitation of 313 nm, all the samples showed a strong far-red emission (698 nm) of Eu3+ ions and obviously enhanced with increasing dimensionality. The enhanced luminescence was attributed to the synergic effect of the internal electric field and oxygen vacancies. To verify this concept, the photocatalytic properties of the samples are characterized. As a consequence, BiOCl:Eu3+ 3D HPs displayed the best photocatalytic activity for the degradation of RhB under visible light illumination. This work further uncovered the intrinsic reasons for the morphology dependence of the luminescence performance of BiOCl:Ln3+ microcrystals.

Biochars treated with acids always presented enhanced sorption capacities for heavy metals. Biochars pyrolyzed at various temperatures have different compositions and present different oxidation states for the acid treatment. To optimize the surface oxidation of biochars, an appropriate pyrolysis temperature of biomass is of great importance. In this work, raw biochars prepared from Typha angustifolia at 300, 400, 450, 500 and 600 °C were oxidized by HNO3. The function of HNO3 mainly focused on the surface oxidation of biochars rather than the creation of micropores in matrixes. Biochars pyrolyzed at the higher temperature were more difficult to be oxidized by the acid. The HNO3-activated biochars (NABCs) enriched Pb(II) and Cd(II) under various geochemical conditions including contact time, pH, ionic strengths, coexisting HA, initial heavy metal concentrations and temperatures. NABCs exhibited excellent sorption capacities (i.e., 232.6 mg/g for Pb(II), 88.9 mg/g for Cd(II) at pH 5.0 and 298 K) which were 6.9 and 5.5 times higher than these of untreated biochars. The maximum uptake capacities toward Pb(II) and Cd(II) showed an excellent linearity with the values of [O C O content × Surface area], demonstrating the essential role of the surface O C O species to coordinate heavy metals. NABCs could be well reused for six cycles through desorption using the acid pickling.

The development of methods for real-time monitoring the level of Cys in biological system is a topic of continued importance. Furthermore, the probes emitting in the NIR region are favorable for cell imaging because of their low phototoxcity and high signal-to-noise ratio (S/N) in living cells. In the paper, we have developed a novel lysosome-targeting NIR xanthene-benzothiozolium dye BHCy-OH by taking advantage of the heteroatom replacement strategy to regulate the absorption and emission wavelengths of the known semi-heptamethine dye. Subsequently, the NIR probe BHCy-A with high sensitivity for Cys has been synthesized. The dye BHCy-OH and the Cys-selective probe BHCy-A emitted fluorescence at 735 nm in PBS buffer, and are lysosome-targetable in living cells. Because the lysosome-targeting abilities of them do not demand proton participation, we believe that they are very useful for investigation the function of lysosomes and for interpreting the function of lysosomal Cys in living-cell imaging.

Substitutional heterovalent doping has been considered as an effective method to control optical properties of lanthanide doped phosphors in the past, but it focuses only on three-dimensional and insulating crystal hosts. This study aimed to report the efficient upconversion enhancement of Er3+ induced by a new strategy of Ca2+ heterovalent doping in the layered semiconducting host based on BiOCl crystals concentrated by van der Waals force. The surface photovoltage (SPV) tests, theoretical calculations and optical probing effect of Eu3+ ions provided evidence that the replacement of Bi3+ with Ca2+ strengthened the macroscopic polarization and the corresponding spontaneous internal electric field (IEF) along the [001] of the BiOCl crystal sheet. The upconversion (UC) red and green emission intensities of the sample co-doped with 10 mol% Ca2+ ions were enhanced 39 and 12 times, respectively, compared with those of the Ca2+-free sample. Moreover, this study showed that the higher separation efficiency of photocarriers led to the prolongation of the decay time of excited energy levels under the strengthened intrinsic IEF by Ca2+-heterovalent doping, which was partially responsible for the UC photoluminescence (PL) enhancement of Er3+. This work not only provided new insight into the method for the engineering of UC emissions but also enhanced the understanding of layered semiconducting materials to modify the transition of lanthanide ions.

The efficient extraction of uranium is challenging for radioactive wastewater treatment. Concerning to the specific coordination of functional groups with radionuclides, the development of ideal sorbents with high surface area, enhanced porosity and abundant functional groups compatibly to uptake uranium selectively is of great significance. Biochar, an attractive material to concentration aquatic targets, exhibits a positive correlation of surface area and pore volume of biochars with pyrolysis temperature, whereas a negative relation of surface functionality with thermolysis temperature. Here we applied a facile and environmental-friendly ball-milling technique to engineer raw biochars in the presence of phytic acid. Ball-milling treatment increased the external surface area of biochars by reducing grain sizes, as well as enhanced the micropore surface area by exposing blocked micropore networks. P-containing moiety was grafted to the surface of biochar matrix successfully. The physicochemical characteristics of biochars enabled a high uptake capacity (128.5 mg/g) and favorable selectivity of U(VI). It suggested that ball-milling of raw biochars with activating solvents could achieve an excellent performance for the efficient concentration of aquatic uranium.

Properly engineering of surface functionality and structural porosity is critical to improve the sorption performance of biochars. Herein, we report a facile one-pot preparation of phosphate group-functionalized biochars (PBs) derived from bamboo sawdust by engineering with phytic acid prior to pyrolysis. High specific surface areas (629, 1298 and 1109 m2·g−1), large pore volumes (0.332, 0.919 and 0.789 cm3·g−1), and abundant phosphorous contents (1.14, 3.32 and 1.53 at.%) are achieved compatibly for the PBs pyrolyzed at given temperatures (i.e., 300, 450 and 600 °C) which are significantly higher than those of pristine biochars. Phytic acid not only releases hydrogen protons to tailor biochar matrixes to make micropores created and further developed, but also provides organic phosphorous-containing moiety to guarantee the surface phosphate functionality. PBs extract U(VI) from aqueous media efficiently, i.e., equilibrium achieved within 8 h, high sorption capacity of 229.2 mg·g−1 (at pH 4.0, T 298 K), and favorable selectivity towards U(VI) against the interference of coexisting metal ions. PBs can be regenerated by 0.1 mol·L−1 Na2CO3 and reused well after six recycles. This present work provides a path for the design and synthesis of advanced biochars with favorable potentials in the extraction of U(VI)-containing effluents.

The non-auditory effects of noise exposure on the central nervous system have been established both epidemiologically and experimentally. Chronic noise exposure (CNE) has been associated with tau hyperphosphorylation and Alzheimer's disease (AD)-like pathological changes. However, experimental evidence for these associations remains limited. The aim of the current study was to explore the effects of CNE [100 dB sound pressure level (SPL) white noise, 4 h/d×14 d] on tau phosphorylation in the rat hippocampus and the prefrontal cortex. Forty-eight male Wistar rats were randomly assigned to two groups: a noise-exposed group and a control group. The levels of radioimmunoprecipitation assay (RIPA)-soluble and RIPA-insoluble phosphorylated tau at Ser202, Ser396, Ser404, and Ser422 in the hippocampus and the prefrontal cortex were measured at different time points (days 0, 3, 7, and 14) after the end of the last noise exposure. Exposure to white noise for 14 consecutive days significantly increased the levels of tau phosphorylation at Ser202, Ser396, Ser404, and Ser422, the sites typically phosphorylated in AD brains, in the hippocampus and the prefrontal cortex. Tau hyperphosphorylation persisted for 7 to 14 d after the cessation of noise exposure. These alterations were also concomitant with the generation of pathological neurofibrillary tangle (NFT) tau 3, 7 and 14 d after the end of the stimulus. Furthermore, lasting increases in proteins involved in hyperphosphorylation, namely glycogen synthase kinase 3β (GSK3β) and protein phosphatase 2A (PP2A), were found to occur in close correspondence with increase in tau hyperphosphorylation. The results of this study show that CNE leads to long-lasting increases in non-NFT hyperphosphorylated tau and delayed formation of misfolded NFT tau in the hippocampus and the prefrontal cortex. Our results also provide evidence for the involvement of GSK3β and PP2A in these processes.

The aim of the present study was to examine the protective effects and mechanisms of S100 calcium-binding protein A4 (S100A4) on endothelial cell apoptosis induced by oxidative stress injury. Endothelial cells were cultured and divided into control and oxidative stress injury groups, with the latter state induced by H2O2. Endothelial cells in every group were incubated with or without 50 or 100 µM S100A4. The cell viability and amounts of malondialdehyde, nitric oxide and lactate dehydrogenase in the culture medium were measured. The apoptotic index was detected by TUNEL staining. Western blot and immunoprecipitation analyses were used to detect the expression levels and the association between S100A4 and P53. H2O2 treatment led to oxidative stress injury in the cultured vascular endothelial cells, a decrease in the cell viability and an increase in the rate of apoptosis of vascular endothelial cells compared with the negative control group. Exogenous S100A4 serves a significant function against oxidative stress injury (P

Ma, A.; Lu, J., and Wang, T., 2012. Effects of elevation and vegetation on methane emissions from a freshwater estuarine wetland. Methane (CH4) emission rates from three different tidal elevations were measured in a freshwater wetland of the Yangtze River, China, estuary using a modified, static, closed-chamber technique. The intertidal zone covered by Phragmites australis is a source of atmospheric CH4. The site at a higher elevation had lower CH4 emissions than did a lower-elevation site (1.322 ± 1.15 mg m−2 h−1 vs. 11.66 ± 12.5 mg m−2 h−1). Methane emissions from the mudflats were negligible. Methane emissions showed remarkable seasonal variations, with the largest emissions occurring in summer and late-summer and the smallest emissions occurring in early spring. Although CH4 emissions were related to soil temperature at depths of 5–10 cm, differences in CH4 emissions among sites were mainly determined by the presence of P. australis. Simulatied experiments did not find significant differences...

A novel 3-(4-methoxybenzylamino) propanoic acid substituted water-soluble zinc phthalocyanine (CNPcZn) was synthesized. The interaction between CNPcZn with calf thymus DNA (CT DNA) was studied using spectroscopic methods. The studies indicated that CNPcZn has strong affinity to CT DNA, and furthermore, CNZnPc showed excellent photodamaging activity to CT DNA. Above results indicated that such CNPcZn has great potential to be used as an effective photosensitizer in the field of photodynamic therapy.