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The photo and electro catalytic activity of graphic carbon nitride (g-C 3 N 4) depended strongly on the component, band gap, and thickness. In this paper, superior thin g-C 3 N 4 composition homojunctions were created via a seed growth process by controlling precursor components. The result exhibited the change of microstructure, band gap, and photo and electro chemical properties of samples. Photocatalytic H 2 generation and the photodegradation of rhodamine B (Rh B) were carried out to test photocatalytic activities. g-C 3 N 4 seeds were fabricated using melamine and dicyandiamide named as MCN and DCN, respectively. The homojunctions were fabricated by the thermal polymerization of dicyandiamide using MCN as seeds. Because of a type II structure and high stability, sample 600MCN@720DCN10% revealed the best H 2 generation which was ∼20 times of that of g-C 3 N 4 nanosheets. The photocatalytic degradation of Rh B was completed within 15 min using this homojunction sample. In contrast, the homojunctions fabricated by the thermal polymerization of melamine using DCN as seeds revealed enhanced electrochemical performance. Sample 600DCN@720MCN exhibited the lowest overpotential and the best H 2 evolution reaction performance. The result suggested the formation of homojunction improves photo and electrocatalytic activities. • Superior thin g-C 3 N 4 composition homojunctions were created via a seed growth by controlling precursor components. • Photocatalytic H 2 generation and the photodegradation of rhodamine B were tested for photocatalytic activities. • Sample 600MCN@720DCN10% revealed the best H 2 generation which was ∼20 times of that of g-C 3 N 4 nanosheets. • The homojunctions also revealed enhanced electrochemical HER activity. [ABSTRACT FROM AUTHOR]

Monodispersed WP nanoparticles were encapsulated in nitrogen-doped carbon (NC) layers via thermal polymerization at high temperature. The intimate interface between WP and NC accelerated charge transfer and elevated the electroconductivity. As-prepared WP@NC nanocomposites revealed enhanced electrocatalytic hydrogen evolution reaction (HER) activities in both of acidic and alkaline electrolytes with Tafel slopes of 73 and 85 mv/dec, respectively. Furthermore, WP@NC nanocomposites instead of noble metal co-catalysts were loaded on superior thin g-C 3 N 4 nanosheets (CN) by thermal polymerization at different temperature. In the case of without Pt, the photocatalytic hydrogen generation rate of CN/WP@NC heterojunctions prepared using optimized conditions reached 1217.6 μmol g−1 h−1, which was ∼196 folds of pure g-C 3 N 4 nanosheets. This is ascribed to that N-doped carbon layers on WP improved the separation and transfer efficiency of photogenerated charge carriers. Interestingly, the carbon layers improved the chemical stability and corrosion resistance to ensure enhanced photocatalytic hydrogen generation in simulated seawater. In addition, the sample revealed outstanding light-assisted elimination capability of 4-nitrophenol (4-NP) because of the selective hydrogenation reaction to 4-aminophenol and photodegradation reaction of 4-NP. Under visible light irradiation, the removal efficiency using CN/WP@NC reached 99% within 10 min. The kinetic constant (0.443 min−1) was 17.8 times of that of g-C 3 N 4 nanosheets. This work supplied an efficient method to fabricate bi-functional noble-metal-free catalyst towards clean energy production and environment remediation. [Display omitted] [ABSTRACT FROM AUTHOR]

The growth of WS 2 on S-doped graphic carbon nitrides (g-C 3 N 4) was controlled to utilize horizontal implanting and get fine interfacial characteristic. Superior thin S-doped g-C 3 N 4 nanosheets were fabricated via a two-step thermal polymerization at high temperature. Subsequent solvothermal procedure was used to create WS 2 /S-g-C 3 N 4 (WS 2 /SCN) photocatalytic heterojunctions with optimized component ratios, in which doped S components in g-C 3 N 4 play an important role for the horizontal growth and homogeneous distribution of WS 2 nanosheets. Z-scheme charge transfer mechanism was proposed according to various characterizations. Photocatalytic rhodamine B (Rh B) degradation test indicated that WS 2 /SCN 15 % (sample WS 2 /SCN-3) revealed the best performance, in which Rh B of 92.8 % was photocatalytic oxidated with 20 min. Photocatalytic hydrogen generation experiments indicated that sample WS 2 /SCN-3 exhibited a H 2 generation rate of 1380 μmol·g−1∙h−1, which was 3.7 times of that of S-g-C 3 N 4 nanosheets. These WS 2 /S-g-C 3 N 4 heterojunctions also exhibited excellent performance for photocatalytic H 2 O 2 evolution. Sample WS 2 /SCN-3 exhibited a H 2 O 2 generation rate of 5216 μmol·g−1·h−1 which was 6.4 times that of S-g-C 3 N 4 sample. This excellent photocatalytic activity is scribed to WS 2 /S-g-C 3 N 4 layered heterojunctions with well-developed interface characteristic. The result supplied an efficient approach for the preparation of photocatalysts. • WS 2 horizontally grown on S-doped graphic carbon nitrides (g-C 3 N 4) to get fine interfacial characteristics. • S doping plays an important role for the horizontal growth and homogeneous distribution of WS 2 nanosheets. • Z-scheme charge transfer mechanism was proposed according to various characterizations. • Photocatalytic H 2 generation test suggested that sample WS 2 /S-g-C 3 N 4 revealed a H 2 generation rate of 1380 μmol·g-1·h-1. • The H 2 O 2 evolution rate of WS 2 /S-g-C 3 N 4 was 5216 μmol·g-1·h-1 which was 6.4 times of that of S-g-C 3 N 4. [ABSTRACT FROM AUTHOR]

• The fuel pellet with a core-shell structure was designed by an in-situ process. • The relationship between the shell thickness and mixing parameters were studied. • An empirical formula for the shell thickness and mixing parameters was established. Using the segregation phenomenon of different materials in the mixing process, the dispersion nuclear fuel pellet with a core-shell structure was firstly designed and fabricated by an in-situ preparation process. This core-shell structure could prevent the metal matrix from reacting with water to generate hydrogen, which improves the safety property of the pellet. Furthermore, it provides a perspective on integrated manufacture of pellets and claddings by one-step preparation. Effects of mixing process parameters on the shell thickness were investigated in detail. The results indicate that: a three-quarter cycle sinusoid could be used to describe the change in shell thickness with rotational speed; and there is a negative linear relationship between shell thickness and volume percentage of ZrO 2 microspheres; the shell thickness increases as the particle size difference of ZrO 2 microspheres/glass beads increases. What's more, an empirical formula describing the relationship between the shell thickness and these parameters has been established. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon dots (N-Cdots) with enhanced absorption in visible light region were combined with TiO 2 (B)/anatase (TiO 2 (A + B)) microspheres consist of nanosheets via a one-step synthesis. The successful connection of N-Cdots and TiO 2 substrate was confirmed by the appearance of new Ti–O–C bond. The degradation rate of Rhodamine B (RhB) for N-Cdots@TiO 2 (B)/anatase was improved to seven times higher than that of initial TiO 2 (B) microspheres under full spectrum illumination. N-Cdots@TiO 2 (B)/anatase photocatalyst also exhibited high photocatalytic ability under visible light irradiation. The possible mechanism was proposed in two irradiation conditions. N-Cdots act as a semiconductor to generate electrons and holes. The electrons were transferred to the conduction band of TiO 2 (B) and anatase, which improved the visible light utilization efficiency. Meanwhile, the heterophase structure of TiO 2 (A + B) substrate restrained the recombination of electron-hole pairs. It is the synergistic effect of heterophase and N-Cdots that enhanced the photocatalytic performance. Image 1 • TiO 2 (B)/anatase microspheres loaded with N-doped carbon dots (N-Cdots) were prepared. • N-Cdots connected with TiO 2 via Ti–O–C bond rather than simple adsorption interaction. • N-Cdots act as a semiconductor to generate electron-hole pairs and enhanced photocatalytic in visible light. • The synergistic effect of N-Cdots and TiO 2 (B)/anatase elevated photocatalysis in full spectrum. [ABSTRACT FROM AUTHOR]

Using carbon spheres and sucrose as the carbon sources, two kinds of color-tunable carbon dots (Cdots) named as Cdots-C and Cdots-S were prepared via change the solution concentration. As the concentration of Cdots solution increased, varying degrees of self-assembly occur between monodisperse Cdots. Hence aggregates with different types formed, which can be observed. Appearance of new excitation bands at 465 and 520 nm caused by H- and J-type Cdots aggregates caused the emission at long wavelengths. At the same time, the excitation band at 300–400 nm induced blue-green emission and the competitions of three excitation bands resulted in the color-tunable PL behaviour which cover the region from green to red emission. The difference of carbon sources of Cdots-C, Cdots-S and Cdots-G (graphite) explained the reason why concentration-dependent PL behaviour were not observed in Cdots-G at a high solution concentration. The process of self-assembly were ascribed to hydrogen bonding interaction between abundant hydroxyl groups on the surface of Cdots-C and Cdots-S. This work provided a simple approach to modulate photoluminescence (PL) color of Cdots and will extend the application in bioimaging. Image 1 [ABSTRACT FROM AUTHOR]

Highly luminescent CdTe quantum dots (QDs) is a typical luminescent material with great application potential. The photoluminescence (PL) and stability of the QDs depended strongly on Cd precursors, ligand (e.g. thioglycolic acid TGA) and preparation conditions. In this paper, CdTe QDs were prepared using Cd precursors with various molar ratios of TGA/Cd at different conditions. The composition of Cd-precursors depend strongly on the molar ratios of TGA/Cd and storage time due to the formation of Cd-TGA clusters which affects strongly the surface states of the QDs. The effect of the preparation conditions of Cd-precursors (e.g. molar ratios of TGA/Cd) on the PL peak wavelength, the full width at half maximum of PL spectra, PL quantum yields (PLQYs), fluorescence lifetime, and stability were tested in detailed. Interestingly, the PLQYs of the QDs prepared using a large molar ratio of TGA/Cd remarkably increased after Cd precursor stored in dark conditions for long time. This confirms that Cd-TGA clusters in the precursors drastically affected the synthesis of the QDs. The mechanism was discussed in detailed. These aqueous CdTe QDs with high PLQYs were obtained using a molar ratio of TGA/Cd of 1.25. In addition, the PL peak position of the QDs was red-shifted with increasing temperature, but is back to the initial value after cooling down to room temperature. Cycle test indicates red-emitting QDs reveal high stability. [ABSTRACT FROM AUTHOR]

Carbon nanotubes with well conductivity can improve photogenerated carrier separation and transport for enhanced photocatalytic performance. In this paper, Ni nanoparticles embedded N-doped carbon nanotubes (CNTs) were decorated on superior thin g-C 3 N 4 nanosheets as a co-catalyst via a mechano-chemical pre-reaction and thermal polymerization at high temperature. The admirable conductivity and unique one-dimensional structure of Ni-decorated CNTs (NiCNTs) generated more active sites and supplied efficient charge transfer. Abundant unpaired electron and π-conjugated structure of N-doped CNTs promoted the delocalization, retarded recombination, and stabilized charge separation. Ni nanoparticles acted as active sites to trap photogenerated electrons for photoreduction reaction. g-C 3 N 4 /NiCNTs composites with an optimized ratio revealed a hydrogen (H 2) generation rate as high as 1050.4 μmol g−1 h−1, exhibiting an increase of ∼137 times compared with pure g-C 3 N 4 without using Pt as co-catalyst. The H 2 generation rate was even higher than that of g-C 3 N 4 /Pt, suggesting that NiCNTs can substitute noble metals completely. In addition, the g-C 3 N 4 /NiCNTs sample removed 4-nitrophenol (4-NP) within 10 min under visible light irradiation. The rate constant of g-C 3 N 4 /NiCNTs sample was ∼49 times of that of pristine g-C 3 N 4. This work proposed a novel bifunctional catalyst for pollutant treatment and clean energy production. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, a method for preparing high expansion ratio, high cell density PLA foams based on a combination of titanium dioxide(TiO 2) and lignin(Lg) is demonstrated. TiO 2 can act as a rigid core to generate heterogeneous nucleated crystals and increase the strength of the PLA matrix, Lg can be used as a polymer plasticizer with good dispersibility to improve the mobility of PLA molecular chains and reduce the entanglement between molecular chains. By studying the competition and synergy of two nucleating agents in the nucleation process, Lg exhibits a significant nucleation-promoting effect compared to TiO 2 in the case of a single nucleating agent. While adding 5 wt% TiO 2 /Lg, the high content of TiO 2 /Lg provided the best synergistic effect to accelerate the overall crystallization. In addition, the 1 wt% PLA/Lg composite foams prepared in this work also exhibited excellent foaming properties. [Display omitted] • Significance of the Work: In this paper, PLA/TiO 2 /Lg foamed materials were prepared by supercritical carbon dioxide foaming. The effects of TiO 2 /Lg competition and synergism on crystallization and foaming behavior were studied. A new method to regulate the foaming performance of PLA through the relationship between fillers was provided. Avrami equation was used to quantitatively analyze the effect of filler competition and synergism on crystallization behavior, and the same conclusion was obtained through activation energy analysis. When adding a filler alone, Lg and TiO 2 compete with each other, and Lg plays a leading role in nucleation. When adding TiO 2 /Lg at the same time, 5 wt% TiO 2 /Lg cooperates with each other, providing the highest nucleation rate to accelerate the overall crystallization. The foaming properties, mechanical properties and oil absorption properties of the foaming materials were further analyzed. The experimental results show that PLA/TiO 2 /Lg foaming materials have excellent crystallization and foaming properties. • What it contains that is most important, new or original. • The effect of competition and synergism of fillers on the crystallization and foaming properties of PLA was studied. • Based on Avrami equation and activation energy, the nucleation activity and the competition and synergy between them were qualitatively analyzed. • The effects of the interface between crystalline and amorphous regions and the number of bubble nuclei on the gas path and nucleation mechanism were studied. • Lg can be used as soft phase to provide plasticization in the matrix, and TiO 2 as hard phase in the matrix can improve the melt strength. • The foaming material has excellent compression resistance and oil absorption capacity. [ABSTRACT FROM AUTHOR]

A one-step thermal polymerization method was developed to create homogeneous metallic cobalt (Co) clusters on graphitic carbon nitride (g-C 3 N 4) nanosheets. The size (less than 3 nm) and distribution of Co clusters were controlled by a subsequent acid treatment. Because of the nanofluidic channels, efficient charge transfer, and enhanced light harvesting ability, optimized Co/g-C 3 N 4 nanoarchitectonics by acid treatment revealed excellent photocatalytic activities. The visible-light photocatalytic H 2 generation, H 2 O 2 evolution and NO removal rate of the nanoarchitectonics were 82, 4, and 2 times of those of g-C 3 N 4 nanosheets, respectively, suggesting that integrating transition metal clusters on g-C 3 N 4 nanosheets is a novel strategy for NO removal and water splitting. Interestingly, Co/g-C 3 N 4 nanoarchitectonics were further heat-treated at high temperature to create Co clusters decorated N-doped carbon nanosheets, in which ideal performance in hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction in alkaline solution were observed. This result supplied an efficient route to construct non-noble metal multifunctional catalysts. • A one-step method was developed to embedded Co clusters on g-C 3 N 4 nanosheets. • Enhanced H 2 generation, H 2 O 2 evolution and NO removal performance indicated the crucial role of Co clusters. • Co clusters also promoted g-C 3 N 4 into N-doped carbon nanosheets towards enhanced electrochemical activity. [ABSTRACT FROM AUTHOR]

The construction of heterostructures is an efficient approach to improve the photocatalystic performance of semiconductors. In this paper, SnO 2 -g-C 3 N 4 (SnO 2 –CN) nanocomposites were created via thermal polymerization using SnO 2 nanoparticles and layered g-C 3 N 4 nanosheets. A mechano-chemical pre-reaction and the second thermal polymerization of bulk g-C 3 N 4 play important roles for the formation of SnO 2 /g-C 3 N 4 heterostructures with improved interface nature. The heterostructures with an optimized SnO 2 weight ratio of 10% was obtained by adjusting parameters for enhanced photocatalytic reactions in visible light region. Hydrogen generation and the degradation of rhodamine B (Rh B) were tested to characterize the photocatalytic performance of the SnO 2 –CN nanocomposites. The degradation of a 20 mg/L Rh B solution was finished within 15 min, in which the degradation rate was about twice compared with superior thin g-C 3 N 4 nanosheets prepared by a two-step polymerization procedure. The SnO 2 –CN nanocomposite with 10% SnO 2 revealed a H 2 generation rate of 2569.5 μmol g−1L−1. The enhanced photocatalytic performance is ascribed to a type II heterostructure formed and improved interface properties between g-C 3 N 4 and SnO 2. In addition, the improved conductivity of SnO 2 promoted the photogenerated carrier separation and transfer. The result provided a new idea for the construction of g-C 3 N 4 heterostructures with improved interface characterization and the improvement of photocatalytic properties. • SnO 2 -g-C 3 N 4 nanocomposites were created via pre-treatment and thermal polymerization. • The degradation of a 20 mg/L Rh B solution was finished within 15 min. • The nanocomposites revealed a H 2 generation rate of 2569.5 μmol g−1L−1. • Type II heterostructures improved interface nature for enhancing photocatalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-Al LDH modified TiO 2 nanobelts were synthesized by a two-step solvothermal method. • A considerable effect of Cr(VI) removal is dual adsorption-photocatalytic mechanism. • Excellent performance is ascribed to the mixed-phase TiO 2 one-dimensional nanostructure. • The uniformly grown LDH improves the conductivity and light absorption of the sample. Co-Al layered double hydroxide (LDH)/TiO 2 heterostructures were synthesized using TiO 2 nanobelts by a solvothermal method. X-ray diffraction analysis and morphology observation indicate that layered Co-Al LDH was grown on TiO 2 nanobelts consisted of anatase and TiO 2 (B). The phase composition of TiO 2 nanobelt samples depended on the calcined temperature. The phase composition of TiO 2 affected the adsorption ability of composite samples. The pseudo-second-order kinetics model fits for the Cr(VI) ions adsorption kinetics of LDH/TiO 2 composite samples. In the case of dark condition, the Cr(VI) removal using composite sample (LT4) was about 45%.In contrast, the Cr(VI) removal of the sample reached up to 100% within 10 min under full solar spectrum irradiation. The excellent performance of the sample can be ascribed to the formation of CoAl-LDH/TiO 2 heterostructures consisted of one-dimensional TiO 2 nanostructure with mixed anatase and TiO 2 (B) phases and optimized LDH loading. This heterostructure revealed relatively high stability. The interface of two phases effectively hinders the recombination of photo-generated carriers. In addition, the presence of uniformly distributed CoAl-LDH improved the conductivity and light absorption of the composite sample. [ABSTRACT FROM AUTHOR]

Pore structure of Polyethyleneimine (PEI)/SBA-15 nanocomposites was investigated by Positron Annihilation Lifetime Spectroscopy (PALS) in conjunction with other conventional means like TEM, XRD and N 2 adsorption and desorption techniques. In this study, PALS could help us obtain the information of micropores and mesopores in the SBA-15 matrix at same time via analyzing the change of long lifetime components τ 3 and τ 4. The size of micropores and mesopores could be obtained based on theoretical models, which is slightly smaller than the mesopore size obtained by N 2 adsorption and desorption techniques due to the existence of open micropores in the channel. This provides unique tool for understanding the evolution of the nanometer-sized pores in SBA-15 and PEI/SBA-15 composites and quantitative description of the relationship between the materials structure and its CO 2 adsorption capacity in the future. [Display omitted] • Existence of micropores and mesoporous in SBA-15 was revealed by PALS. • The influence of PEI loading on evolution of nanometer-sized pores was investigated. • PEI/SBA-15 composites with CO 2 adsorption capacity up to 2.18 mmol g−1 at 25 °C was obtained. [ABSTRACT FROM AUTHOR]

Using properties of the inverses of annihilation and creation operators of f-oscillator we construct the f-analogues of squeezed vacuum states. If used to describe the motion of a trapped ion, the phase probability distributions of these states for large η are very different from those of the usual squeezed vacuum state. [Copyright &y& Elsevier]

Daidzein and genistein glucuronides (DG and GG), major isoflavone metabolites, may be partly responsible for biological effects of isoflavones, such as estrogen receptor binding and natural killer cell (NK) activation or inhibition. DG and GG were synthesized using 3-methylcholanthrene-induced rat liver microsomes. The Km and Vmax for daidzein and genistein were 9.0 and 7.7 micromol/L, and 0.7 and 1.6 micromol/(mg protein. min), respectively. The absence of ultraviolet absorbance maxima shifts in the presence of sodium acetate confirmed that the synthesized products were 7-O-glucuronides. DG and GG were further purified by a Sephadex LH-20 column. DG and GG competed with the binding of 17beta-(3H) estradiol to estrogen receptors of B6D2F1 mouse uterine cytosol. The concentrations required for 50% displacement of 17beta-(3H) estradiol (CB50) were: 17beta-estradiol, 1.34 nmol/L; diethylstilbestrol, 1.46 nmol/L; daidzein, 1.6 micromol/L; DG, 14.7 micromol/L; genistein, 0.154 micromol/L; GG, 7.27 micromol/L. In human peripheral blood NK cells, genistein at <0.5 micromol/L and DG and GG at 0.1-10 micromol/L enhanced NK cell-mediated K562 cancer cell killing significantly (P < 0.05). At > 0.5 micromol/L, genistein inhibited NK cytotoxicity significantly (P < 0.05). The glucuronides only inhibited NK cytotoxicity at 50 micromol/L. Isoflavones, and especially the isoflavone glucuronides, enhanced activation of NK cells by interleukin-2 (IL-2), additively. At physiological concentrations, DG and GG were weakly estrogenic, and they activated human NK cells in nutritionally relevant concentrations in vitro, probably at a site different from IL-2 action. [ABSTRACT FROM AUTHOR]

• A novel hybrid of MoS 2 decorated with hollow Fe 3 O 4 /Fe 1−x S nanocube were synthesized. • The photo-Fenton and adsorption behavior of this hybrid were investigated. • The optimized sample performs excellent photo-Fenton and adsorption performance. • The construction way of structure is helpful to develop other catalysts and adsorbents. Photo-Fenton catalysts enable to completely remove contaminants from water with its advanced oxidation technology. In this paper, a layered hollow Fe 3 O 4 /Fe 1−x S@MoS 2 composite as photo-Fenton catalyst and adsorbent was reported to remove organic dyes and antibiotics from water. First, Prussian blue is subjected to ion exchange and subsequent calcination to synthesize hollow Fe 2 O 3. Then, a layered hollow composite material Fe 3 O 4 /Fe 1−x S@MoS 2 was synthesized by simple in situ hydrothermal growth of MoS 2 with Fe 2 O 3 as the substrate. The synthesized sample exhibited excellent photo-Fenton degradation performance and high adsorption capacity. Under the condition of unregulated pH, the degradation of 20 mg/L RhB solution just carried out within 4 min using 0.2 g/L of Fe 3 O 4 /Fe 1−x S@MoS 2 -50 %. The result indicates that strong oxidizing of OH is the main active species. In addition, the maximum adsorption capacity of Fe 3 O 4 /Fe 1−x S @MoS 2 -50 % sample adsorbed tetracycline hydrochloride reached 748.9 mg/L. The adsorption process follows pseudo-second-order kinetics model and Freundlich isotherm model. It is confirmed that the sample revealed fine cycle stability in both the photo-Fenton and the adsorption process. Moreover, the material has ferromagnetism for easy recycling. The layered hollow composite Fe 3 O 4 /Fe 1−x S @MoS 2 can be used as an excellent catalyst and adsorbent for environmental treatment. This present work provides new insight into the synthesis of photo-Fenton catalyst and adsorbent for sewage treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The composite is degradable and has excellent water retention capacity. • The biodegradable and renewable PLA and LG are used in this research. • LG regulates the crystallization of PLA and improves its degradability. • The synergism of PEG and LG improves crystallization and hydrophilicity of PLA. In this paper, a green degradable composite film containing lignin (LG), polyethylene glycol (PEG) and polylactic acid for building maintenance was prepared by solution casting method. The effects of PEG and LG on the crystallization, degradation, water retention and surface properties of the composite films were studied. The crystallinity of the composite membrane containing PEG and LG was increased to 69.97 %, and its water retention performance was the best, and the water loss rate was only 0.17 %. The degradation performance of the composite film was significantly improved due to the good hydrophilicity of PEG and LG. As a green water retaining material, the composite film has a good application prospect in the field of building. [ABSTRACT FROM AUTHOR]

Abstract: The multipartite entangled state for the total momentum and relative coordinates of n particles is constructed. The corresponding quantum-mechanical operator with respect to the classical transformation , , , in the state is investigated. [Copyright &y& Elsevier]

The synthesis of high efficiency noble metal free catalysts is an important target for H 2 production by water-splitting. In this work, rGO/CdS@MoS 2 heterostructure with two catalytic paths was successfully synthesized and as the first applied the heterostructure in the field of electrocatalysis. The MoS 2 structure is adjusted by controlling hydrothermal process. Moreover, the effects of structure and loading amount of 2H–MoS 2 , 1T-MoS 2 and amorphous MoS 2 (A-MoS 2) on catalytic performance were also studied. The catalytic activity of rGO/CdS@MoS 2 heterostructure has been improved obviously. Compared with 2H–MoS 2 , the distortion of 1T-MoS 2 and the defect of A-MoS 2 make it have more unsaturated S, so rGO/CdS@1T-MoS 2 and rGO/CdS@A-MoS 2 have better catalytic activity. For photocatalytic H 2 evolution, loading MoS 2 and rGO on catalysts changes the energy band structure, promotes the separation of electron-holes and provides a large number of active sites. Among them, the visible light photocatalytic H 2 production rate of rGO/CdS@1T-MoS 2 with 0.1 mol of 1T-MoS 2 (CT0.1-G1) is 18.26 mmol/g/h. During the electrocatalytic H 2 evolution, introducing MoS 2 and rGO improves electronic structure and increases active sites. rGO/CdS@1T-MoS 2 with 0.5 mol of 1T-MoS 2 (CT0.5-G1) shows the low overpotential (312 mV) and Tafel slopes (85 mV/dec). • rGO/CdS@MoS 2 heterostructure with two catalytic paths was synthesized. • Phase composition of MoS 2 was adjusted by controlling hydrothermal process. • The phase and amount of MoS 2 are critical for catalytic performance. • rGO/CdS@1T-MoS 2 and rGO/CdS@A-MoS 2 revealed better catalytic activity. [ABSTRACT FROM AUTHOR]

Dietary n-3 polyunsaturated fatty acids (n-3 PUFAs) increase insulin signaling in skeletal muscle. In the current study, we investigated the effect of eicosapentaenoic acid (EPA) on insulin-induced mammalian target of rapamycin (mTOR) phosphorylation in myotubes. We showed that EPA did not affect basal and insulin-induced mTOR phosphorylation in myotubes. However, EPA abolished lipopolysaccharide (LPS) -induced deficiency in insulin signaling ( P < 0.05). Pre-incubation of nuclear factor κB (NF-κΒ) and c-Jun N-terminal kinases (JNK) inhibitors prevented the decreased insulin-induced mTOR phosphorylation elicited by LPS ( P < 0.05). In addition, in protein tyrosine phosphatase-1B (PTP1B) knockdown myotubes, LPS failed to decrease insulin-induced mammalian target of rapamycin (mTOR) phosphorylation in myotubes ( P > 0.05). In myotubes, LPS stimulated PTP1B expression via NF-κB and activation protein-1 (AP1). Pre-incubation of 50 μM EPA prevented the LPS-induced activation of AP1 and NF-κΒ as well as PTP1B expression ( P < 0.05). Interestingly, incubation of peroxisome proliferator-activated receptor γ (PPARγ) antagonist (GW9662) prior to EPA treatment, the effect of EPA on insulin-induced mTOR phosphorylation was blocked. Accordingly, EPA did not inhibit the LPS-induced activation of AP1 or NF-κΒ as well as PTP1B expression when incubation of GW9662 prior to EPA treatment. The in vivo study showed that EPA prevented LPS-induced PTPT1B expression and a decrease in insulin-induced mTOR phosphorylation in muscle of mice. In summary, EPA abolished LPS inhibition of insulin-induced mTOR phosphorylation in myotubes, and one of the key mechanisms was to inhibit AP1 and NF-κB activation and PTP1B transcription. [ABSTRACT FROM AUTHOR]

This paper studied the cracking mode and mechanism of the large press die holder. Detailed investigations including macroscopic examination, metallographic observation, microfractography, chemical analysis and mechanical properties analysis were carried out. The investigations reveal that the failure mechanism of the die holder is fast brittle fracture caused by high stress under the condition of material embrittlement. The main crack originated from the fillet of the die holder. The serious impact toughness degeneration at the bottom of the die holder resulted in the material embrittlement. The transmission electron microscopy (TEM) investigation indicates that the material properties degeneration is related to the coarsening precipitates of M 23 C 6 and M 6 C. The finite element analysis (FEA) demonstrates that the fillet suffering high stress is the weak part of the die holder. [ABSTRACT FROM AUTHOR]

Systemic sclerosis (SSc) is an autoimmune disease characterized by immune disorders, vascular obliteration, excessive extracellular matrix deposition, skin fibrosis, and further pathological change of internal organs. To date, the exact etiology of this complicated disease remains unknown. Over the past few years, the roles of epigenetic modifications caused by environmental factors have been intensively studied in relation to the disease pathogenesis, and important advances have been made. This review focuses on the new advances of microRNAs (miRNAs) in the field of SSc research, including the upstream regulatory factors of miRNAs, the downstream targets, and the feedback mechanisms between miRNAs and their targets. We also discussed the correlation of miRNAs and DNA methylation, the miRNAs and the gene polymorphism. Overall, the findings presented in this review illustrated how miRNAs play important roles in the pathogenesis of SSc. However, several unanswered questions continue to impede our understanding of this complex disease. Future research should focus on the identification of new biomarkers for early diagnosis and prognosis, which will help us improve the clinical treatment of patients with SSc. In addition, we discussed the challenges of miRNA study in SSc in the future. Since the miRNA injection may be a promising therapeutic approach for SSc treatment, one of the challenges in the future is to evaluate the therapeutic effects of miRNA and anti-miRNAs using SSc model animals. In light of the fact that one miRNA can target many mRNAs, and one mRNA is targeted by many miRNAs, the effect of miRNA changes on other gene expression should be investigated to evaluate the treatment safety of miRNA injection in vivo. [ABSTRACT FROM AUTHOR]

In previous study, we identified that microRNA (miR)-152 expression was down-regulated in RA model rats, and overexpression of miR-152 inhibited the canonical Wnt signaling through the DNA methyltransferase (DNMT1) inhibition. However, the exact molecular mechanisms of DNMT1 were unclear. In this work, we investigate whether DNMT1 affects the pathogenesis of RA model rats and targets the miR-152 promoter. The effects of DNMT1 on the canonical Wnt signaling, the pathogenesis of RA model rats and the SFRP1 expression were detected by the real time qPCR, Western blotting, ELISA, MTT and viable cell number assay. The interaction between miR-152 and DNMT1, methyl CpG binding protein 2 (MeCP2) was investigated by real time qPCR and chromatin immunoprecipitation (ChIP). Our results revealed that increased DNMT1 activated the canonical Wnt signaling could not only by targeting SFRP4 may also by SFRP1 in RA model rats. Furthermore, treatment of DNMT1 inhibitor, 5-aza-2′-deoxycytidine (5-azadC), or knockdown of DNMT1, or knockdown of MeCP2 led to increased miR-152 expression by reversion of its promoter hypermethylation, DNMT1 and MeCP2 binding to the CpG islands of miR-152 promoter. Interestingly, it is proved a synergistic inhibition effect of DNMT1 and MeCP2 in this process. Moreover, overexpression of miR-152 could inhibit DNMT1 expression and result in a decrease of DNMT1 and MeCP2 binding to miR-152 promoter, and inhibition of miR-152 expression would reverse it. These observations demonstrate a crucial functional crosstalk between miR-152 and the DNMT1, MeCP2 by a double-negative circuit involved in the pathogenesis of RA model rats. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a symmetrical polyarticular autoimmune disease of unknown etiology. In this present study, we observed that the adenomatous polyposis coli ( APC ) expression is down-regulated and the expression of microRNA (miR)-663 increased significantly in synovium from RA patients compared with control. Target gene prediction for miR-663 revealed that the mRNA of APC gene, which is a member of the canonical Wnt signaling pathway, has a miR-663 binding site in its 3′-untranslated region (3′UTR). The result showed that increased miR-663 suppressed the APC expression significantly, and this down-regulation of AP C expression triggered the activation of canonical Wnt signaling through accumulation of β-catenin in fibroblast-like synoviocytes (FLS). In addition, increased miR-663 induced the FLS proliferation and the expression MMP3 and fibronectin during disease development. Therefore, miR-663 can be considered as a critical regulator of RA pathogenesis and can be utilized for developing miRNA-based therapeutic agents for RA patients. [ABSTRACT FROM AUTHOR]

Whether the rheumatoid arthritis (RA) pathogenesis is regulated by microRNA (miRNA) is not entirely clear. In this study, we found that miR-375 was down-regulated significantly in fibroblast-like synoviocytes (FLS) in adjuvant-induced arthritis (AIA) rat model compared with control. Because the web-based software TargetScan and PicTar predict Frizzled 8 (FZD8) as the target of miR-375, we investigated whether up-regulated miR-375 plays a role in the activation of the canonical Wnt signaling by targeting the FZD8. Furthermore, the purpose of the present experiments was also to determine the role of miR-375 in the pathogenesis of AIA rat model and to ascertain the effects of FZD8 in this process. Real time qPCR, Western blotting, ELISA and ChIP assay were used to assess the inhibited role of miR-375 in the pathogenesis of AIA rat model and the canonical Wnt signaling. RNA interference was also used to detect the role of knockdown of dephosphorylated β-catenin. Luciferase reporter gene and related methods were performed to determine the FZD8 as the target of miR-375. The increased miR-375 inhibited the pathogenesis of AIA rat model as indicated by decreases in the several disease markers, such as MMP3 and fibronectin. Interestingly, miR-375 also inhibited the canonical Wnt signaling, and the stabilized form of β-catenin blocked the miR-375 effects. FZD8 was identified as the target of miR-375 in AIA rat model by the firefly luciferase reporter gene. In summary, our results demonstrate that miR-375 regulates the pathogenesis of AIA rat model through the canonical Wnt signaling pathway. This discovery may provide new targets for therapeutic intervention to benefit RA patients. [ABSTRACT FROM AUTHOR]

In order to improve the electrocatalytic hydrogen evolution reaction (HER), semiconductor heterojunctions must be further developed. In the present investigation, three-dimensional scaffold-like networks, consisting of gold (Au), bismuth sulfide (Bi 2 S 3), and molybdenum disulfide (MoS 2), have been developed and constructed. The main purpose was to improve the HER performances of a MoS 2 -based material. A MoS 2 /Bi 2 S 3 heterostructure was, at first, prepared by using a hydrothermal synthesis technique and a Bi 2 WO 6 precursor. The resulting MoS 2 /Bi 2 S 3 network was found to exhibit a disk-like morphology with a homogeneous scaffold structure. The Au@MoS 2 /Bi 2 S 3 ternary composite structure was, thereafter, synthesized by depositing Au nanoparticles on the MoS 2 /Bi 2 S 3 heterostructure. As a result of the following HER measurement, the onset overpotential of Au@MoS 2 /Bi 2 S 3 was observed to decrease to 72 mV, and the Tafel slope decreased to 40 mV/dec. The three different materials (within Au@MoS 2 /Bi 2 S 3) were found to contribute to these positive results. The Bi 2 S 3 structure promoted the electronic charge transport, while the dispersed MoS 2 structure exposed more active sites. Furthermore, the deposited Au nanoparticles promoted the conduction of electrons from the nanoparticles to the hydrogen carriers and were also found to accelerate the complete HER process (by reducing the activation energy of HER). Owing to these excellent catalytic performances, the here presented results will aid in the construction of a composite semiconducting material with improved electrocatalytic performances. • The bismuth sulfide (Bi 2 S 3) uniformly supports molybdenum sulfide (MoS 2) nanosheets. • MoS 2 /Bi 2 S 3 heterojunction shows excellent hydrogen evolution performance. • Au@MoS 2 /Bi 2 S 3 ternary composite structure is synthesized by reduction deposit on of Au. • The performance improvement of Au@MoS 2 /Bi 2 S 3 is ascribed to structural and electronic effects. [ABSTRACT FROM AUTHOR]