Efficient Degradation of Rhodamine B with the BiOCl/Bi2Fe4O9 Heterojunction Photocatalyst.

BiOCl/Bi2Fe4O9 photocatalyst was prepared by a coprecipitation-hydrothermal method. The heterojunction structure generated by the composite of BiOCl and Bi2Fe4O9 reduced the electron-hole recombination efficiency and improved the degradation rate of RhB. At 240 min, 20% BiOCl/Bi2Fe4O9 represented the excellent degradation effect on 10 mg/L RhB; the degradation efficiency reached 99.56%; and the reaction rate constant was 0.01534 min-1, which was 5.76 times and 6.06 times that of Bi2Fe4O9 and BiOCl, respectively. The main active substance of the photocatalytic degradation of dyes was superoxide radical O2-·. Five cycles of the experiment proved the relative stability of BiOCl/Bi2Fe4O9.

Mesoporous ZnO nanosheet as gas sensor for sensitive triethylamine detection.

In this paper, mesoporous ZnO nanosheets were synthesized by the hydrothermal method using polystyrene-polyacrylic acid (PS-PAA) as the template. The morphology, structure, and composition of the samples were characterized by SEM, TEM, XRD, and XPS, and the physical properties of the samples were tested by N2 adsorption-desorption curve. The results showed that the mesoporous ZnO nanosheets presented a flower-like appearance. Each flower is composed of flake petals which consist of nanoparticles of different sizes, with a large specific surface area. Gas sensitivity test results show that the ZnO gas sensor has good triethylamine (TEA) sensing performance. Its response to 50 ppm TEA can reach 43.771, and the detection limit is as low as 1 ppm, showing the characteristics of rapid response/recovery.

[Effects of curcumol on liver function and fibrosis in rats of nonalcoholic fatty liver disease and its mechanism].

Objective: To investigate the effects and mechanism of curcumol (CC) on liver function and fibrosis in rats of nonalcoholic fatty liver disease (NAFLD). Methods: The rat models of nonalcoholic steatohepatitis (NASH) combined with liver fibrosis were constructed by high-fat diet. Sixty SD rats were randomly divided into blank control group, model group (NASH), NASH + Compound Biejiarangan Troche (CBT) group (positive control group), and NASH + CC groups (25, 50, 100 mg/kg) , 10 rats in each group. The percentage of liver to body weight, and the levels of high density lipoprotein (HDL), triglyceride (TG), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. The liver fibrosis was observed by HE staining. The expressions of α-smooth muscle actin (α-SMA) and positive staining of nuclear factor κB p65 (NF-κB p65) were detected by immunohistochemistry. The expression levels of α-SMA, matrix metalloproteinase-1 (MMP-1), tissue inhibitor of metalloproteinase-1 (TIMP-1) and toll-like receptor-4 (TLR4), transforming growth factor-activated kinase-1 (TAK1), NF-κB p65 and vascular cell adhesion molecule-1 (VCAM-1) were detected by Western blot. The expression levels of interleukin (IL-6, IL-10, IL-1ß) and tumor necrosis factor-α (TNF-α) were detected by enzyme linked immunosorbent assay (ELISA). Results: Compared with blank control group, the contents of HDL and IL-10 and the expression level of MMP-1 protein were decreased in model group significantly (P＜0.05), while the levels of TG, ALT and AST, the positive rate of P65, α-SMA, TIMP-1, TLR4, TAK1, NF-κB p65, VCAM-1, IL-6, TNF-α and IL-1ß were increased significantly (P＜0.05). Compared with model group, the levels of HDL, IL-10 and MMP-1 protein were significantly increased after treatment with CBT and CC (P＜0.05), while the levels of TG, ALT, and AST, the positive rate of P65, α-SMA, TIMP-1, TLR4, TAK1, NF-κB p65, VCAM-1, IL-6, TNF-α and IL-1ß were decreased significantly (P＜0.05). The improvement in model+high- concentration CC group was the most significant, and which in all concentration groups was lower than that in model+CBT group (P＜0.05). Conclusion: CC can reduce inflammation response and improve liver function by regulating TLR4, TAK1 and NF-κB/p65 signaling pathway, and thus alleviating liver fibrosis, showing concentration-dependence within certain range.

Double-layer capsule of mesoporous ZnO@SnO2 for sensitive detection of triethylamine.

To overcome obstacles such as low response and poor selectivity of pure ZnO and SnO2 gas sensors, the ZnO@SnO2 sensor was synthesized by hydrothermal synthesis. The samples were characterized by XRD, XPS, SEM, HRTEM, N2 adsorption-desorption and other techniques. The results show that ZnO@SnO2 forms an n-n-type heterostructure and presents a double-layer capsule with a size of 0.5-4 µm. The results show that compared with pure ZnO and SnO2, the ZnO@SnO2 sensor exhibits a higher response (138.9) to 50 ppm triethylamine (TEA) at 152°C, which is 19.56 times that of the pure ZnO sensor and 21.7 times that of the SnO2 sensor. It has a short response/recovery time (11/11 s), excellent selectivity and cycling stability. Compared with other volatile organic compounds or gases, it has higher selectivity for TEA detection.

Transparent and Stretchable Graphene Electrode by Intercalation Doping for Epidermal Electrophysiology.

Epidermal electronics is regarded as the next-generation technology, and graphene is a promising electrode, which is a key building block of such devices. However, graphene has a tendency to crack at small strains with a rapidly increased resistance upon stretching. Here, to enable graphene applicable in epidermal electronics, we designed a novel graphene structure that is molybdenum chloride (MoCl5)-intercalated few-layer graphene (Mo-FLG) fabricated in a confined environment. In the case of bilayer graphene (BLG), MoCl5-intercalated bilayer graphene (Mo-BLG) exhibited a low sheet resistance of 40 Ω/square (sq) at a transmittance of 80%. Due to the self-barrier doping effect, the sheet resistance increased to only 60 Ω/sq after exposing to the atmosphere over 1 month. Transferred onto elastomer substrates, Mo-BLG can work as an electrode up to 80% strain and maintain a high conductivity that is durable over 2000 cycles at 30% strain. This mechano-electrostability is attributed to the special intercalated structure where the intercalated dopants act as lubricants to weaken the layer-layer interaction and allow a certain degree of sliding, as well as electrical crack-connectors to bridge the cracked domains at a high strain. Mo-BLG can be applied as epidermal electrodes to monitor electrophysiological signals such as electrocardiogram (ECG), electrooculogram (EOG), electroencephalography (EEG), and surface electromyogram (sEMG) with high signal-to-noise ratios (SNRs) comparable to commercial Ag/AgCl electrode. This is the first demonstration of epidermal electrodes based on intercalation-doped graphene applied in health monitoring, shedding light on the future development of graphene-based epidermal electronics.

Hydrangea-like mesoporous WO3 nanoflowers with crystalline framework for 3-hydroxy-2-butanone sensing.

In this study, a simple and efficient strategy for the construction of hydrangea-like mesoporous WO3 nanoflowers templated using diblock copolymer PS119-PtBA129 was developed. The nanoflower shows good gas sensing properties, especially for 3-hydroxy-2-butanone (3H-2B), which is the signature metabolite of Listeria monocytogenes (L. monocytogenes). Therefore, the gas sensing of 3H-2B by hydrangea-like mesoporous WO3 nanoflowers can be used to detect L. monocytogenes. In the case of 25 ppm 3H-2B as target gas, the response (Ra/Rg) of the hydrangea-like mesoporous WO3 nanoflowers at 205 °C is 152, where Ra and Rg are the resistances of the sensing device in air and target gas, respectively, and the response and recovery times at 25 ppm are 25 s and 146 s, respectively. Schematic illustration of the formation of hydrangea-like mesoporous WO3 nanoflowers and its gas sensing implication.

Visible-light-driven photocatalytic degradation of rhodamine B in water by BiOClxI1-x solid solutions.

Bismuth oxyhalides (BiOXs, X = Cl, Br and I) are emerging photocatalytic materials with unique layered structure, flexible band structure and superior photocatalytic activity. The purpose of this study was to develop a facile alcoholysis route to prepare BiOClxI1-x nanosheet solid solutions at room temperature. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence emission spectroscopy (PL) and Brunauer-Emmett-Teller (BET) surface area analyzer were used to characterize the as-prepared photocatalysts. These results revealed that two-dimension BiOClxI1-x nanosheet solid solutions could be obtained with high percentage of {001} crystal facets exposed. Moreover, the formation of solid solution could regularly change the optical absorption thresholds and band gaps of BiOClxI1-x photocatalysts. The photocatalytic experiments indicated that BiOCl0.75I0.25 exhibited the highest photocatalytic performance for the degradation of Rhodamine B (RhB) under simulated sunlight irradiation and the photocatalytic process followed a pseudo-first-order kinetic equation. A possible mechanism of RhB photodegradation over BiOClxI1-x solid solutions was proposed based on the structural properties of BiOClxI1-x solid solutions and RhB photosensitization.

Cable-Like Core-Shell Mesoporous SnO2 Nanofibers by Single-Nozzle Electrospinning Phase Separation for Formaldehyde Sensing.

In this study, we have developed a simple and efficient single-nozzle electrospinning strategy involving the phase separation of polystyrene and poly(vinylpyrrolidone) to construct cable-like core-shell mesoporous SnO2 nanofibers. Compared with traditional multi-axial electrospinning approaches to the synthesis of core-shell nanofibers, the single-nozzle electrospinning process requires no complex multi-axial electrospinning setups or post-treatments, just drying and annealing after electrospinning. The obtained SnO2 nanofibers show promise as a sensing material for formaldehyde at low concentrations, the detection limit being about 1 ppm. Furthermore, the nanofibers exhibited good cycling stability and selectivity, with response and recovery times toward 10 ppm formaldehyde being approximately 18 and 196 s, respectively, at an operating temperature of 195 °C.

Direct Growth of Continuous and Uniform MoS2 Film on SiO2/Si Substrate Catalyzed by Sodium Sulfate.

Because of its unique electronic band structure, molybdenum disulfide (MoS2) has been regarded as a star semiconducting material. However, direct growth of continuous and high-quality MoS2 films on SiO2/Si substrates is still very challenging. Here, we report a facile chemical vapor deposition (CVD) method based on synergistic modulation of precursor and Na2SO4 catalysis, realizing the centimeter scale growth of a continuous MoS2 film on SiO2/Si substrates. The as-grown MoS2 film had an excellent spatial homogeneity and crystal quality, with an edge length of the composite domain as large as 632 µm. Both experimental and theoretical results proved that Na tended to bond with SiO2 substrates rather than to interfere with as-grown MoS2. Thus, they showed decent and uniform electrical performance, with electron mobilities as high as 5.9 cm2 V-1 s-1. We believe our method will pave a new way for MoS2 toward real application in modern electronics.

Shape-Engineered Synthesis of Atomically Thin 1T-SnS2 Catalyzed by Potassium Halides.

Shape engineering plays a crucial role in the application of two-dimensional (2D) layered metal dichalcogenide (LMD) crystalline materials in terms of physical and chemical property modulation. However, controllable growth of 1T phase tin disulfide (SnS2) with multifarious morphologies has rarely been reported and remains challenging. Herein, we report a direct synthesis of large-size, uniform, and atomically thin 1T-SnS2 with multiple morphologies by adding potassium halides via a facile chemical vapor deposition process. A variety of morphologies, i.e., from hexagon, triangle, windmill, and dendritic to coralloid, corresponding to fractal dimensions from 1.01 to 1.81 are accurately controlled by growth conditions. Moreover, the Sn concentration controls the morphology change of SnS2. The edge length of the SnS2 dendritic flake can grow larger than 500 µm in 5 min. Potassium halides can significantly reduce the surface migration barrier of the SnS2 cluster and enhance the SnS2 adhesion force with substrate to facilitate efficient high in-plane growth of monolayer SnS2 compared to sodium halides by density functional theory calculations. More branched SnS2 with higher fractal dimension provides more active sites for enhancing hydrogen evolution reactions. Importantly, we prove that potassium halides are preferable for 1T-phase LMDs structures, while sodium halides are more suitable for 2H-phase materials. The growth mechanism proposed here provides a general approach for controllable-phase synthesis of 2D LMD crystals and related heterostructures. Shape engineering of 2D materials also provides a strategy to tune LMD properties for demanding applications.

Morphogenesis and Molecular Phylogeny of a Soil Ciliate Uroleptoides longiseries (Foissner, Agatha and Berger, 2002) Berger 2008 (Ciliophora, Hypotrichia).

Morphogenesis of the hypotrich ciliate Uroleptoides longiseries, isolated from sandy soil beside the Yellow River, Suide, Yulin, Shaanxi Province, China, was investigated using protargol staining. The main events during binary fission are as follows: (1) the long frontoventral row is formed by a single anlage; (2) five frontoventral-transverse cirral anlagen are formed in primary mode; (3) only the posterior part of the parental adoral zone of the membranelles is renewed; and (4) the oral primordium of the opisthe is formed intrakinetally. This is the first detailed record of all stages of morphogenesis for Uroleptoides. We also provide the first record of the small subunit ribosomal DNA (SSU rDNA) sequences for U. longiseries. Phylogenetic analyses based on the SSU rDNA sequences data show that Uroleptoides longiseries clusters with U. magnigranulosa with moderate to high support which together form a clade with Orthoamphisiella breviseries. These three species share the morphogenetic feature of the long frontoventral row being formed by a single anlage.

Acute benzo[a]pyrene treatment causes different antioxidant response and DNA damage in liver, lung, brain, stomach and kidney.

Acute effects of oxidative damage induced by benzo[a]pyrene (B[a]P) on various organs are still not clear. In this study, we investigated oxidative stress and DNA damage in liver, lung, stomach, brain and kidney of ICR male mice induced by acute B[a]P treatment. B[a]P treatment led to a significant decrease at the different doses in body weight. For the variations of superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione (GSH) and GSH/GSSG, significant increases were observed at 24 h, then decreased till 72 h after B[a]P injection. The increase percent indicated in a dose- dependent decrease manner. However, glutathione peroxidase (GPx), GSSG and MDA were significantly increased in a time- and dose-dependent increase manner. DNA damage showed the significant and top levels at 24 h, and increased in proportion to the doses of B[a]P treatment. The total induction could be indicated by the variation of MDA at 24 h after B[a]P injection and showed the following order of predominance: lung > liver > kidney = stomach > brain. This was further certificated by histopathological changes in the examined organs. Additionally, the levels of serum glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), and blood urea nitrogen (UN), creatinine were also significantly increased at 24 h after B[a]P injection. These findings suggested the disturbance of antioxidant responses and aggravation of DNA damages, and the different responses on various organs induced by acute B[a]P treatment in organism.

Process optimization on methyl orange discoloration in Fe3O4/RGO-H2O2 Fenton-like system.

The development of a catalyst with high catalytic activity was one of the most important issues for the heterogeneous Fenton-like process. In this study, nanocomposites of Fe3O4 anchored onto reduced graphene oxide (RGO) were prepared by a moderate alkaline-thermal precipitation method and developed as highly efficient heterogeneous Fenton-like catalysts. The characterization results indicated that Fe3O4 nanoparticles (NPs) were tightly anchored onto few-layer RGO sheets via a strong interaction. Contrast experiments showed that Fe3O4/RGO nanocomposites had much better Fenton-like catalytic activity than Fe3O4 NPs. The process optimization of methyl orange (MO) discoloration in Fe3O4/RGO-H2O2 system was accomplished by central composite design under response surface methodology. A second-order polynomial model was established to predict the optimal values of MO discoloration and its significance was evaluated by analysis of variance. Three-dimensional response surfaces for the interaction between two variables were constructed. Based on the model prediction, the optimum conditions for MO discoloration in Fe3O4/RGO-H2O2 system were 2.9 for solution pH, 16.5 mM H2O2 concentration, 2.5 g/L catalyst dosage and 33.5 min of reaction time, with the maximum predicted value for MO discoloration ratio of 99.98%.

Morphology and morphogenesis of a new soil urostylid ciliate, Australothrix xianiensis nov. spec. (Ciliophora, Hypotrichia).

The living morphology, infraciliature and morphogenetic events of a new soil urostylid ciliate, Australothrix xianiensis nov. spec., collected from Chanba National Wetland Park in Xi'an, China, were studied in vivo and after protargol preparation. Australothrix xianiensis nov. spec. is characterized as follows: about 190-240 × 40-60 µm in life; body pisciform and dark; cortical granules arranged in longitudinal rows on both sides, colourless, rod-shaped and about 2 × 1 µm in size; single contractile vacuole slightly ahead of mid-body with two long collecting canals; macronuclear nodules scattered throughout cytoplasm; adoral zone occupies about 20% of body length, composed of about 32 membranelles; three frontal cirri and one buccal cirrus; two to four midventral pairs and four or five midventral rows, one left and two right marginal rows; four or five dorsal kineties; four or five caudal cirri. The main features of divisional morphogenesis are: (1) each posterior streak generates a midventral row together with the midventral pair; (2) the old adoral zone of membranelles is retained with the exception of the posterior part, which is renewed in situ; the undulating membranes are completely renewed; (3) parental cirri do not contribute to the construction of the oral primordium in the opisthe in very early dividers; (4) two sets of frontoventral cirral anlagen are formed.

Cooperative Multifunctional Catalysts for Nitrone Synthesis: Platinum Nanoclusters in Amine-Functionalized Metal-Organic Frameworks.

Nitrones are key intermediates in organic synthesis and the pharmaceutical industry. The heterogeneous synthesis of nitrones with multifunctional catalysts is extremely attractive but rarely explored. Herein, we report ultrasmall platinum nanoclusters (PtNCs) encapsulated in amine-functionalized Zr metal-organic framework (MOF), UiO-66-NH2 (Pt@UiO-66-NH2 ) as a multifunctional catalyst in the one-pot tandem synthesis of nitrones. By virtue of the cooperative interplay among the selective hydrogenation activity provided by the ultrasmall PtNCs and Lewis acidity/basicity/nanoconfinement endowed by UiO-66-NH2 , Pt@UiO-66-NH2 exhibits remarkable activity and selectivity, in comparison to Pt/carbon, Pt@UiO-66, and Pd@UiO-66-NH2 . Pt@UiO-66-NH2 also outperforms Pt nanoparticles supported on the external surface of the same MOF (Pt/UiO-66-NH2 ). To our knowledge, this work demonstrates the first examples of one-pot synthesis of nitrones using recyclable multifunctional heterogeneous catalysts.

Morphogenesis of a saline soil ciliate Urosoma salmastra (Dragesco and Dragesco-Kernéis, 1986) Berger, 1999 with notes on the phylogeny of Urosoma (Ciliophora, Hypotrichia).

Morphogenesis in a population of Urosoma salmastra collected from saline soil in Weinan, China, was investigated using protargol staining. The main morphogenetic event that characterizes U. salmastra is the inclusion of cirrus III/2 in the formation of the frontoventra-transverse cirral anlagen. We also provide small subunit ribosomal DNA gene sequences for a population of U. salmastra and for two populations of U. emarginata. The molecular phylogeny indicates that Urosoma is not monophyletic, viz, U. emarginata branches separately from its congeners and the closest relative of U. salmastra is Oxytricha granulifera.

Morphology, morphogenesis and molecular phylogeny of a new soil ciliate Paragonostomoides xianicum n. sp. (Ciliophora, Hypotrichia, Gonostomatidae).

A hypotrichous ciliate, Paragonostomoides xianicum n. sp., was discovered in soil on the surface of the Xi'an Circumvallation, Xi'an, China. Its morphology and some major ontogenetic stages were studied and the phylogenetic position was estimated using standard methods Paragonostomoides xianicum n. sp. is characterized as follows: body size about 75-90×15-25µm in vivo, elliptical and flexible; colourless mitochondrion-like cortical granules scattered throughout cell surface, about 0.8×0.6µm in size; contractile vacuole positioned at mid-body; frontoventral row IV extends beyond buccal vertex and frontoventral row VI extends to about body end; frontoventral cirri not in pairs; transverse cirri absent; three caudal cirri; two macronuclear nodules and one to four micronuclei. The ontogenetic process in P. xianicum n. sp. is basically similar to that in Metagonostomum gonostomoidum and Gonostomum-species and featured by: frontoventral-transverse cirri develop in five-anlage pattern, the rearmost cirri generated in the two rightmost FV anlagen are not set off posteriorly (like an ordinary TC), as well as FVT-anlagen n and n-1 form in secondary mode in P. xianicum. Phylogenetic analyses based on small subunit ribosomal DNA sequence data reveal a close relationship of P. xianicum n. sp. with Cotterillia bromelicola and two Gonostomum-species.

Metal-Organic-Framework-Derived Carbons: Applications as Solid-Base Catalyst and Support for Pd Nanoparticles in Tandem Catalysis.

The facile pyrolysis of a bipyridyl metal-organic framework, MOF-253, produces N-doped porous carbons (Cz-MOF-253), which exhibit excellent catalytic activity in the Knoevenagel condensation reaction and outperform other nitrogen-containing MOF-derived carbons. More importantly, by virtue of their high Lewis basicity and porous nature, Cz-MOF-253-supported Pd nanoparticles (Pd/Cz-MOF-253-800) show excellent performance in a one-pot sequential Knoevenagel condensation-hydrogenation reaction.

Heterogeneous Fenton-like discoloration of organic dyes catalyzed by porous schorl ceramisite.

Due to the difficult separation of superfine schorl powder (SSP) from solution after being used, millimetre-scale porous schorl ceramisite (PSC) was obtained through solid-phase sintering method and used as a heterogeneous catalyst for Fenton-like discoloration of organic dyes. SSP and PSC were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The results demonstrated that both SSP and PSC were mainly composed of schorl and there existed large amounts of micropores on the surface of PSC. A series of control experiments indicated that PSC exhibited higher Fenton-like catalytic activity than SSP. Methylene blue (MB) discoloration in both PSC-H2O2 and SSP-H2O2 systems followed pseudo-first-order kinetics and the reaction rate constant k1 obtained in PSC-H2O2 system was 3.23 times as large as the one in SSP-H2O2 system. Then, the process optimization of MB discoloration in heterogeneous Fenton-like reaction catalyzed by PSC was operated by central composite design under response surface methodology. Based on the model prediction, the optimum conditions for MB discoloration in this system were determined.

Synergic Effect between Adsorption and Photocatalysis of Metal-Free g-C3N4 Derived from Different Precursors.

Graphitic carbon nitride (g-C3N4) used in this work was obtained by heating dicyandiamide and melamine, respectively, at different temperatures. The differences of g-C3N4 derived from different precursors in phase composition, functional group, surface morphology, microstructure, surface property, band gap and specific surface area were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-visible diffuse reflection spectroscopy and BET surface area analyzer, respectively. The photocatalytic discoloration of an active cationic dye, Methylene Blue (MB) under visible-light irradiation indicated that g-C3N4 derived from melamine at 500°C (CN-M500) had higher adsorption capacity and better photocatalytic activity than that from dicyandiamide at 500°C (CN-D500), which was attributed to the larger surface area of CN-M500. MB discoloration ratio over CN-M500 was affected by initial MB concentration and photocatalyst dosage. After 120 min reaction time, the blue color of MB solution disappeared completely. Subsequently, based on the measurement of the surface Zeta potentials of CN-M500 at different pHs, an active anionic dye, Methyl Orange (MO) was selected as the contrastive target pollutant with MB to reveal the synergic effect between adsorption and photocatalysis. Finally, the photocatalytic mechanism was discussed.