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Abstract For the first time, KBaGd(MoO 4) 3 :Eu3+ phosphors were synthesized by sol-gel method and its structure, morphology and luminescent properties were characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), excitation and luminescent spectra. The results show that shape and the particle size distribution of samples synthesized by sol-gel method were more regular and narrower than those synthesized by solid state method. Under the excitation of near UV light (395 nm), an intensive red emission band around 617 nm corresponding to the transition of 5D 0 →7F 2 was observed. The effects of the dose of citric acid, pH value of precursor solution and concentration of Eu3+ ions on the morphology and luminescent properties of the samples were also analyzed. The phosphors show the highest emission intensity as the molar ratio of citric acid to metal ions (C:M) was 2:1, and the optimum concentration of Eu3+ was x = 0.8. The thermal stability of the KBaGd 0.2 (MoO 4) 3 :0.8Eu3+ phosphor was investigated in the framework of crossover mechanism, and the activation energy was determined to be 0.264eV. Lastly, a red LED was fabricated using the as-synthesized phosphor and its luminescent performances were investigated. Highlights • For the first time, KBaGd(MoO 4) 3 :Eu3+ phosphors were synthesized by sol-gel method. • The FT-IR, excitation and emission spectra, luminescent decay curves of the samples were recorded. • The effects of citric acid concentration, pH value on the morphology and luminescent properties of the samples were analyzed. • The thermal stability of the KBaGd 0.2 (MoO 4) 3 :0.8Eu3+ phosphor was investigated in the framework of crossover mechanism. • A red LED was fabricated using the as-synthesized phosphor and its luminescent performances were investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • The UCN@ZIS/SWNTs composite with different V Zn concentrations was constructed for photocatalytic CO 2 reduction. • The UCN was acidified to regulate the surface-active site for CO 2 activation and H 2 O dissociation. • The SWNTs further improves the separation efficiency of photogenerated electron-hole pairs by providing charge transfer channels. • The UCN@rZIS/SWNTs composite displays excellent photocatalytic performance and CH 4 selectivity. Zinc vacancy (V Zn) concentrations were successfully regulated on the hierarchical flower spherical ZnIn 2 S 4 (ZIS) by controlling the hydrothermal temperature. The photo-electrochemical experiments indicated that the carrier separation efficiency of ultrathin-g-C 3 N 4 @ZIS/SWNTs (UCN@ZIS/SWNTs) composite with different V Zn concentrations (poor-V Zn ZIS (pZIS) and rich-V Zn ZIS (rZIS)) had an efficient improvement because of the construction of UCN@ZIS heterojunction and the multiple channels for charge transfer provided by SWNTs. In-situ FTIR results indicate that the presence of V Zn and the enriched surface-active site on UCN contributes to CO 2 activation and H 2 O dissociation. Additionally, the yield of CO and CH 4 over UCN@rZIS/SWNTs composite reached 33.7 µmol g−1 and 39.8 µmol g−1, respectively, and the selectivity of CH 4 reached 54.1 % under the synergistic effect of V Zn , the surface-active site of UCN and charge-transfer channels. This work established an ideal defect model for enhancing CO 2 photocatalytic reduction performance and product selectivity, which may provide a new way to improve photocatalytic efficiency and a better understanding of the photocatalytic reaction mechanisms. [ABSTRACT FROM AUTHOR]

• Two diazatetraasteranes were synthesized by regioselective photocycloaddition. • The synthesis and crystal characteristics of two diazatetraasteranes were compared and analyzed. • The crystal packing of 3,9-diazatetraasterane had a layered arrangement and 3,6-diazatetraasterane had a zigzag-shaped arrangement. 3,6-diazatetraasterane and 3,9-diazatetraasterane are diazatetraasterane derivatives and cage-dimers of 1,4-dihydropyridine in head-to-head or head-to-tail manner by the regioselective [2+2] photocycloaddition. They were synthesized and their structures were verified by NMR spectra, high-resolution mass spectrometry, and Single-crystal X-ray diffraction. The results showed that the molecular structure of 3,6-diazatetraasterane with a C 1 symmetric property and the 3,9-diazatetraasterane with a C 2 symmetric property. The molecular packing arrangement of 3,6-diazatetraasterane was in the zigzag-shape, and the 3,9-diazatetraasterane was in layer-like architecture. The non-covalent interaction (NCI) and Hirshfeld surface analysis were conducted to characterize and visualize the intramolecular and intermolecular interactions. The molecular electrostatic potential (MEP) was calculated to predict electrophilic and nucleophilic regions. The results will provide a theoretical basis for further studies on chemical properties and pharmacological application of the azatetraasterane derivatives. [Display omitted] [ABSTRACT FROM AUTHOR]

One of current ideal thought to reduce the recombination of photogenerated electrons and holes from semiconductors is constructing Multi-dimensional semiconductor-carbon (S-C) heterostructures. As well as acting to photo-degrade the organic contaminant and decrease the toxicity, β-In 2 S 3 is chosen as a potential semiconductors for photocatalysts. Relative good photocatalytic properties delivered on β-In 2 S 3 , however, the fast recombination of photogenerated charge carriers are often appeared, causing reduced further application. Carbon quantum dots (CQDs) involve the introduction of plasma effect into the zero-dimensional nanomaterials in order to arouse an effect: either promoting the charge carriers transfer or plasma energy conversion of the photo-excited CQDs. However, state of the two components also encompass the poor quantum yield existed in the CQDs by its serious agglomeration. Thereby, the delivery of extraordinary ballistic electrical and thermal conductivity on single-walled carbon nanotubes (SWNTs), have shown potential for use in a variety of semiconductors decorating application. Herein, we show that a novel CQDs@In 2 S 3 /SWNTs composite in the Multi-dimensional (3D) hierarchical superstructures with an enhanced photocatalytic efficiency. The ESR analysis and free radicals trapping experiments indicated that the O 2 • − and h + were the main active species for the photocatalytic degradation. The potential photocatalytic mechanism of the three components is discussed and the direction in the plasma effect exhibited in CQDs is also considered, with a particular focus on photocatalytic area. [ABSTRACT FROM AUTHOR]

A series of nebula-like ZnO/CeO 2 @HNTs heterostructure photocatalysts were synthesized via a novel one-step wet-calcination method for degradation of tetracycline (TC) under simulated solar irradiation. TEM, HRTEM, XRD, FT-IR, XPS, DRS, PL, PC, EIS and ESR techniques were applied for characterization of samples. And the potential structure of new photodegradation products was studied by HPLC–MS analysis. The characterization results revealed the enhanced photocatalytic activity of ZnO/CeO 2 @HNTs heterostructure photocatalysts due to the delayed recombination of photogenerated electron-hole pairs. Moreover, surface oxidation state analysis demonstrates that Ce 3+ and Ce 4+ states coexist in CeO 2 , which enhance the separation of electron-hole pairs though cerium oxide shifting between CeO 2 and Ce 2 O 3 under photocatalytic process. In addition, the effects of the calcinating temperature, the molar ratio of ZnO to CeO 2 and the dosage of HNTs on photocatalytic activity of ZnO/CeO 2 @HNTs heterostructure photocatalysts were researched and the best possible values have been found. Furthermore, the photodegradation mechanism was systematically investigated by active species trapping experiment. It revealed that OH radicals play a little role while hole and O 2 − are the more major reactive species in the photodegradation process. [ABSTRACT FROM AUTHOR]

The metal ions play a decisive role in regulating the redox balance of cells and subsequentially alter cellular functions. The pacifying ("cold") or irritating ("hot") effects of food on the human body have been traditionally recognized and utilized by Chinese for hundreds of years. The principal components of fruits and vegetables corresponding to these effects have been identified to be magnesium, iron, and copper cations in combination. This study aims to elucidate the regulatory effects of the three cations on the oxidative responses and inflammatory cytokines production in RAW264.7 macrophages. Two "cold" solutions and two "hot" solutions were prepared with MgSO 4 , FeSO 4 , and CuSO 4. The contents of three cations were calculated with a previously established regression equation and set to the physiologically meaningful levels (at ppm). It was found that the "cold" solution exhibited antioxidant and anti-inflammatory effects in the macrophages. They reduced the intracellular ROS level and restored the mitochondrial respiratory of the AAPH-insulted macrophages, while suppressing the LPS-induced expression of TNF-α, IL-1β, and IL-6 in the cells. Conversely, the "hot" solutions exhibited pro-oxidative and pro-inflammatory effects as they increased the intracellular ROS and expression of inflammatory cytokines in normal cells. It demonstrates the bidirectional regulation of the Mg2+, Cu2+, and Fe2+ cocktails on oxidative and inflammatory responses of murine macrophages. Inspired by the traditional Chinese food concept, the outcome of this study provides a new perspective and useful tool for future research and innovations in healthy and sustainable food. • The Mg2+, Cu2+, and Fe2+ cocktails could bidirectionally regulate the macrophages. • The "cold" mineral solutions exhibited antioxidative and anti-inflammatory activity. • The "hot" mineral solutions possessed pro-oxidative and pro-inflammatory activity. [ABSTRACT FROM AUTHOR]

S-scheme heterojunction of In 2 O 3 /H 1.5 CN/2Au was prepared by hydrothermal, acidizing and calcination methods. The two-dimensional thin layer H 1.5 CN avoided the aggregation of In 2 O 3 and completed the S-scheme charge transfer with In 2 O 3. Moreover, Au not only enhanced the visible light absorption capacity of composites but also provided more active sites for CO 2 reduction. [Display omitted] • S-scheme heterojunction of In 2 O 3 /H 1.5 CN/2Au achieve CO 2 photocatalytic conversion to CO and CH 4. • The enhanced photocatalytic activity results from effective interfacial charge migration and separation and increased active sites. • The LSPR effect of Au improves the utilization of visible light. The construction of S-scheme heterojunction is of great significance for the photocatalytic reduction of CO 2. Here, we prepared two-dimensional (2D) ultra-thin g-C 3 N 4 by acidifying the carbon nitride precursor, and used In 2 O 3 to construct a S-scheme heterojunction with 2D g-C 3 N 4 , and finally In 2 O 3 /H 1.5 CN was modified with Au nanoparticles. The physicochemical properties of the prepared materials were studied by SEM/TEM, XPS, DRS, PL and photochemical test. Meantime, the S-scheme charge transfer mechanism was demonstrated by UPS and ESR. As a result, on the one hand, S-scheme heterojunction accelerated the transfer of electrons on the CB of In 2 O 3 to the VB of g-C 3 N 4 , avoided the recombination of photon-generated carrier. On the other hand, Au, as an effective cocatalyst, promoted photoinduced electron transfer and provided more active sites for CO 2 reduction and the local surface plasmon resonance phenomenon caused by Au NPs enhanced the visible light absorption capacity of the composite material. Moreover, 2D thin layer of g-C 3 N 4 played a carrier effect to disperse In 2 O 3 cube. Therefore, In 2 O 3 /H 1.5 CN/2Au had stable CO 2 reduction products, and the yields of CO/CH 4 reached 141.24/77.05 μmol/g. [ABSTRACT FROM AUTHOR]

The 15D/R achieve near 99.6% selectivity at the gas–solid interface for UV–Vis light-driven CO 2 reduction to CO, with a rate of 42.41 μmol·g−1. The high conductivity of RGO and the strong interaction with DUT-67 enhanced the electron coupling effect, which was conducive to the separation of carriers. The rapid formation of HCOO− and the rapid desorption of CO are responsible for the high CO yield and selectivity. [Display omitted] • The DUT-67/RGO aerogel are first prepared for CO 2 reduction in a gas–solid system. • 15D/R achieve near 99.6% selectivity for UV–Vis light-driven CO 2 reduction to CO. • Separation efficiency of carriers is the main reason for the improvement of CO yield. Herein, DUT-67/RGO aerogel photocatalysts with three-dimensional (3D) macroscopic morphology were first prepared by a facile hydrothermal and freeze-drying process. It was observed that DUT-67 endowed aerogels with strong adsorption/activation capacity for CO 2 molecules. Besides, RGO not only dispersed DUT-67 as a macroscopic carrier, but also improved the utilization rate of light energy. The high conductivity of RGO and the strong interaction with DUT-67 enhanced the electron coupling effect, which was conducive to the separation of carriers. 15D/R achieved near 99.6% selectivity at the gas–solid interface for UV–Vis light-driven CO 2 reduction to CO, with a rate of 42.41 μmol·g−1. The adsorption behavior of products at the interface and formation process of intermediates were monitored based on CO-TPD and in situ Fourier transform infrared spectra. The extremely high selectivity for CO came from the weak adsorption of CO on the surface of 15D/R and formation of CH 4 required more complex intermediates. [ABSTRACT FROM AUTHOR]

Hourly air concentrations of fifty-three non-methane hydrocarbons (NMHCs) were measured at downtown and suburb of Lanzhou, a petrochemical industrialized city, Northwest China in 2013. The measured data were used to investigate the seasonal characteristics of NMHCs air pollution and their contributions to the ozone formation in Lanzhou. Annually averaged NMHCs concentration was 38.29 ppbv in downtown Lanzhou. Among 53 NMHCs, alkanes, alkenes, and aromatics accounted for 57%, 23% and 20% of the total NMHCs air concentration, respectively. The atmospheric levels of toluene and propane with mean values of 4.62 and 4.56 ppbv were higher than other NMHCs, respectively. The ambient levels of NMHCs in downtown Lanzhou were compared with measured NMHCs data collected at a suburban site of Lanzhou, located near a large-scale petrochemical industry. Results show that the levels of alkanes, alkenes, and aromatics in downtown Lanzhou were lower by factors of 3-11 than that in west suburb of the city. O 3 -isopleth plots show that ozone was formed in VOCs control area in downtown Lanzhou and NO x control area at the west suburban site during the summertime. Propylene-equivalent (Prop-Equiv) concentration and the maximum incremental reactivity (MIR) in downtown Lanzhou indicate that cis-2-butene, propylene, and m/p-xylene were the first three compounds contributing to ozone formation potentials whereas in the petrochemical industrialized west suburb, ethane, propene, and trans-2-Butene played more important role in the summertime ozone formation. Principal component analysis (PCA) and multiple linear regression (MLR) were further applied to identify the dominant emission sources and examine their fractions in total NMHCs. Results suggest that vehicle emission, solvent usage, and industrial activities were major sources of NMHCs in the city, accounting for 58.34%, 22.19%, and 19.47% of the total monitored NMHCs in downtown Lanzhou, respectively. In the west suburb of the city, however, vehicle emission was less important as compared with sources from petrochemical industries, as characterized by relatively higher ethane (C 2 H 4 )/ ethyne (acetylene) and propene (C 3 H 6 )/ethyne ratios which ruled out tailpipes emission as major contributors to the VOCs sources. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) CdSe exhibits relatively high photocatalytic abilities for its unique properties, but the aggregation and photocorrosion have blocked its further application. Therefore, for arriving at a solution, alkaline earth metal ions (M = Mg 2+ , Ca 2+ , Sr 2+ and Ba 2+ ) and reduced graphene oxide (rGO) are chosen to fabricated new QDs CdSe-based photocatalytic systems. In this paper, M@CdSe/rGO composites have been synthesized via a facile one-step hydrothermal approach, during which the formation of M doped CdSe crystallization and GO reduction occur simultaneously. The obtained photocatalysts demonstrates synergistically enhanced visible light photocatalytic activity and stability toward photodegrading tetracycline hydrochloride (TC-HCl) solution, especially the introduction of 6 mol% Ca 2+ and 5 wt% GO on QDs CdSe resulted in 85.6% degradation of 15 mg/L TC-HCl in 1 h with 0.5 g/L catalyst. Furthermore, the photodegradation mechanism was systematically investigated by active species trapping experiment. It revealed that h + was the major active species in the destructions process. And the possible process of charge transfer for Ca 2+ @CdSe/rGO nanocomposite was proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

[Display omitted] • This study dynamically monitored antibiotic-derived resistance using a portable Raman spectrometer. • The molecular changes in drug-resistant strains can be rapidly and sensitively recorded by SERS in a whole-cell manner. • PC-LDA applied to bacterial SERS profiles can correctly distinguish among varying degree of resistant strains. • The MIC value showed a non-linear correlation with I 734 / I 867 , and R2 reached above 0.90. • SERS results were consistent with the K−B test, MIC determination, and PCR results. Rapid and quantitative detection of bacterial antibiotic resistance is of great significance for the prevention and treatment of infections and understanding drug-resistant mechanism. In this study, label-free surface-enhanced Raman spectroscopy (SERS) technology was applied to dynamically explore oxacillin/cefazolin-derived resistance in Staphylococcus aureus using a portable Raman spectrometer. The results showed that S. aureus rapidly responded to oxacillin/cefazolin stimulation and gradually developed different degrees of drug resistance during the 21 days of exposure. The molecular changes that accumulated in the drug-resistant strains were sensitively recorded by SERS in a whole-cell manner. Principal components-linear discriminant analysis correctly distinguished various degrees of drug-resistant strains. The typical Raman peak intensities of I 734 / I 867 showed a negative and non-linear correlation with the minimum inhibitory concentration (MIC). The correlation coefficient reached above 0.9. The target sites of oxacillin/cefazolin on S. aureus clearly reflected on SERS profiles. The results collected by SERS were further verified by other biological methods including the antibiotic susceptibility test, MIC determination, and PCR results. This study indicates that SERS technology provides a rapid and flexible alternative to current drug susceptibility testing, laying a foundation for qualitative and quantitative evaluation of drug resistance in clinical detection. [ABSTRACT FROM AUTHOR]

( S )-Enantiomer of an optically active metal free porphyrin bearing four chiral binaphthyl units, namely ( S )-meso-5,10,15,20-tetra-[(11,12:13,14-di(6′-octyl-1′,2′-naphtho)-4,7,10,15,18,21-hexaoxacycloeicosa-phenyl]-porphyrin ( 1 ), was designed, synthesized, and characterized. Comparative studies of the circular dichroism (CD) spectra of ( S )- 1 in chloroform solution and LB film have been carried out, indicating the effective chiral information transfer from the optically active binaphthyl moieties to the porphyrin chromophore at the molecular level. In particular, obvious bisignate Cotton effect is observed in the CD spectrum of the LB film of ( S )- 1 , revealing the right-handed chirality formed in the LB film. In addition, current–voltage ( I – V ) measurement result indicates good semiconductor feature of the LB film formed from ( S )- 1 with conductivity of 1.22 × 10 − 5 S m − 1 . [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) are a promising positive electrode material for super-capacitors (SCs) due to multiple oxidation reduction states. However, the structure of LDH is prone to collapse during the redox reaction and has low conductivity, which further hinders the improvement of capacity performance. Here in, nitrogen-doped graphene quantum dot (N-GQD) is assembled on nickel gallium layered double hydroxide (NiGa-LDH) derived from two-dimension nickel metal organic frameworks (Ni-MOF) on nickel foam (NF) to prepare stable interlaced nano-sheets hybrid structures. As a result of the above synergies, the NiGa-LDH/N-GQD/NF electrode has a high specific capacitance of 2160 F g−1 at 1 A g−1 and good cycling stability with a capacity retention rate of 87.5% in 5000 cycles. In addition, we also make ASC device using NiGa-LDH/N-GQD/NF and Carbon NSs as positive/negative electrodes. The energy density of the assembled ASC device is 78.8 Wh kg−1 at power density of 1432.7 W kg−1, while the capacitance retention after 8000 cycles reaches 81.2%. Meanwhile, individually assembled ASC device can power multiple LEDs in parallel. This work provides an effective way to construct new electrode materials with high energy storage density, good cycling performance and power density by assembling quantum dots into LDH nano-sheets derived from MOF through reasonable design. The NiGa-LDH/N-GQD electrode material prepared on nickel foam has good capacity and cycling stability due to the synergistic effect of interleave NiGa-LDH nano-sheet derived from Ni-MOF and N-GQD embedded in it. [Display omitted] • NiGa-LDH/N-GQD/NF is firstly synthesized by simple hydrothermal method. • The NiGa-LDH derived from the Ni-MOF prepared on nickel foam with interleaved nano-sheet hybrid structure have large specific surface area and can provide more reaction sites. • The introduction of N-GQD plays an important role in improving the electrical conductivity and surface wettability of electrodes. • The NiGa-LDH/N-GQD-2/NF//Carbon NSs asymmetric supercapacitors device (78.8 Wh kg−1) can light multiple LEDs in parallel. [ABSTRACT FROM AUTHOR]

rGO modified g-C 3 N 4 /R-CeO 2 Multi-interface contact S-scheme heterojunction photocatalyst maximizes the transfer efficiency of photogenerated electron and the CO 2 adsorption ability, thus greatly improving the CO 2 photoreduction performance. [Display omitted] • 2D-1D-2D g-C 3 N 4 /R-CeO 2 /rGO photocatalyst has been prepared for CO 2 photoreduction. • 2D-1D-2D multi-interface contact structure is of help for carrier transfer process. • π-π conjugation effect and Ce4+/Ce3+ transformation facilitate electron transmission. • In-situ FTIR and 13C isotope tracer tests analysis the CO 2 photoreduction mechanism. Construction of multi-interface contact step-scheme (S-scheme) photocatalyst is a promising pathway to achieve high-electron transfer efficiency for photocatalytic CO 2 reduction. In this paper, g-C 3 N 4 nanosheets were selected as the main photocatalyst, rod-like CeO 2 (R-CeO 2) with unique Ce4+→Ce3+ conversion property and rGO were loaded on the g-C 3 N 4 surface to construct 2D-1D-2D sandwich photocatalyst. The yields of CO and CH 4 were about 63.18 and 32.67 μmol/g after 4 h when the rGO/R-CeO 2 /g-C 3 N 4 was used as catalyst, which were about 4 and 6 times higher than that of pure CN, respectively. Cyclic experiments proved that the composite had excellent photocatalytic and material stability. Photoelectrochemical tests showed that the construction of S-scheme electron transfer model and the introduction of rGO can great enhance the electron transmission and separation of photogenerated electron-hole pairs. CO 2 adsorption test identified that the loading of R-CeO 2 and rGO obviously enhanced the CO 2 adsorption ability of pure g-C 3 N 4. Density functional theory (DFT) calculations used to analyze the electron transfer path and the formation of the build-in electric field at the semiconductor interface. In-situ FTIR and 13CO 2 element-tracer detection carried out to research the process of CO 2 photoreduction. A possible multi-interface contact S-scheme electron transfer mechanism for enhanced CO 2 photoreduction activity has been discussed. [ABSTRACT FROM AUTHOR]

• LSPR effect enhanced Z-scheme ZnO/Au/g-C 3 N 4 micro needles film (3-ZAC) has been prepared for the photoreduction of CO 2 into CO under UV–vis light irradiation. • Au NPs at the interface of ZnO/g-C 3 N 4 not only act as the electron-transfer bridge, but also as LSPR excited source to speed up the separation of electron-hole pairs photogenerated in the semiconductors. • DFT calculation and FDTD simulation methods has been used to prove the transfer processes of photogenerated electron. The photoproduction of CO from the photocatalytic CO 2 reduction process has been evidenced from 13C isotope tracer tests. • This work demonstrates the importance of the build-in electric field formed at g-C 3 N 4 /ZnO interface and local electromagnetic field of Au NPs for the photoreduction process, providing an inspiring concept for future advancement in this area. Local Surface Plasma Resonance (LSPR) effect enhanced Z-scheme ZnO/Au/g-C 3 N 4 micro-needles film (3-ZAC) has been prepared for the photoreduction of CO 2 into CO under UV–vis light irradiation. Photoreduction experiments show that 3-ZAC has the excellent photocatalytic performance and reusability. The CO production can be achieved 689.7 μmol/m2 after 8 h reaction time, which is 4.5 higher than that of the pure ZnO film. 13C isotope test shows that CO is produced from CO 2 by photoreduction. DFT calculations confirm that build-in electric field formed at g-C 3 N 4 /ZnO interface effectively promoted the electron transfer efficiency in Z-scheme interface. FDTD simulations prove that Au NPs not only act as electron-transfer bridge, but also as LSPR excited source to speed up the separation of electron-hole pairs. In-situ FTIR technique was used to investigate the CO 2 photoreduction process. The above characteristics together maximize the electron transfer efficiency, which causes the material has enhanced photocatalytic performance. [ABSTRACT FROM AUTHOR]

Energy band location and charge separation mechanism of SnS 2 /Au/g-C 3 N 4 system during photoreduction under sunlight irradiation. • The catalyst is prepared by facile thermal treatment and chemical deposition method. • The SnS 2 /Au/g-C 3 N 4 composites show a superior optical adsorption under UV–vis light. • The Au nanoparticle and the Z-type scheme jointly improve the separation of carrier. • The SnS 2 /3ml-Au/g-C 3 N 4 displays the best photoreduction activity and durability. The use of semiconductor photocatalytic reduction technology has higher efficiency and lower energy consumption for CO 2 reduction, but its existence of some mismatched energy band positions and relatively slow charge-hole separation greatly limits its practical application. In this paper, a SnS 2 /Au/g-C 3 N 4 embedded structure model with carbon and nitrogen hybridization is proposed to gain an in-depth understanding of the role of hybridization and precious metal modification in photocatalysis. Carriers were investigated from the perspective of kinetics through photocurrent, LSV curve, and FL spectroscopy. After modification of Au nanoparticles, the photo-excited electrons showed a slower decay process, indicating that the separation of carriers was enhanced, which was further confirmed by impedance and PL spectroscopy. SEM, AFM and TEM analysis confirmed that the 2D face-to-face SnS 2 /Au/g-C 3 N 4 embedded structure was successfully prepared and the Au nanoparticles were evenly distributed. Au nanoparticles not only act as a bridge for electron transport in 2D semiconductor materials to accelerate electron transport, but generate more excited electrons by themselves under the radiation of sunlight, which effectively improves the separation efficiency of electron-hole pairs and enhances the photocatalyst activity. DFT calculations show that the Z-type mechanism and the intercalated energy level of the SnS 2 /Au/g-C 3 N 4 embedded structure expand the light absorption and improve the carrier separation efficiency. As expected, the photocatalyst activity with CO and CH 4 the evolution rate of up 93.81 µmol·g−1·h−1 and 74.98 µmol·g−1·h−1 under visible light irradiation, respectively, while the photocatalytic activity is negligible loss after 30 h photoreduction. This work reveals the role of embedded structure and precious metal modification in the separation and transmission of electron-hole, opening up new perspective for achieving high-efficiency solar CO 2 reduction performance. [ABSTRACT FROM AUTHOR]

Pt@CeO 2 /3DCN heterojunction are prepared by calcination method and photoreduction technology. The enhanced photoreduction of CO 2 performance can be ascribed to the synergistic effects of the oxygen vacancies in CeO 2 for CO 2 activation and heterojunction for electron separation. Besides, Pt nanoparticles (NPs) on CeO 2 /3DCN can further promote the transfer of electrons, resulting in higher photocatalytic activity. • The Pt@CeO 2 /3DCN photocatalyst was successfully synthesized. • Pt@45CeO 2 /3DCN exhibit best ability of CO 2 photoreduction under UV light. • The synergy of CeO 2 and 3DCN improves the photocatalytic performance. The conversion of CO 2 into high value-added carbon-based compounds through photocatalytic reduction technology is considered as one of the more promising strategies to solve the greenhouse effect. And construction of heterojunction photocatalysts can promote the separation of photoelectron-hole pairs, so as to achieve higher activity of photocatalytic CO 2 reduction. Hence, Pt@CeO 2 /3DCN heterojunction are prepared by calcination method and photoreduction technology. The photocatalytic results revealed that Pt@CeO 2 /3DCN show better photocatalytic activity for reducing CO 2 into CO and CH 4 , compared with 3DCN. Especially, Pt@45CeO 2 /3DCN shows the maximum photocatalytic activity of 4.69 and 3.03 μmol·h−1·g−1 for CO and CH 4 under UV light irradiation, respectively, and the reduction activity did not decrease significantly after five cycles. The enhanced photoreduction of CO 2 performance can be ascribed to the synergistic effects of the oxygen vacancies in CeO 2 for CO 2 activation and heterojunction for electron separation. Besides, Pt nanoparticles (NPs) on CeO 2 /3DCN can further promote the transfer of electrons, resulting in higher photocatalytic activity. [ABSTRACT FROM AUTHOR]

Ni x Co 2 Al-LDHs@CC is generated on the carbon cloth by hydrothermal method. The morphology and electrochemical performance are changed by adjusting the molar ratio of Ni to get the best electrochemical performance of Ni 1 Co 2 Al-LDHs@CC. The Ni 1 Co 2 Al-LDHs@CC has a high specific capacity of 1772.5 mC cm−2 at a current density of 1 mA cm−2 and it maintains outstanding capacitive retention of 93.3% after 12,000 cycles. • The effect of Ni on morphology, specific surface area and electrochemical properties of NiCoAl-LDHs is studied for the first time. • Ni 1 Co 2 Al-LDHs@CC with ultrathin nanosheet (15 nm) is synthesized by hydrothermal method. • Ni 1 Co 2 Al-LDHs@CC achieves the maximum specific capacity of 1772.5 mC cm−2. • An asymmetric supercapacitor (0.102 mWh cm−2) can light an 8 mm LEDs. Layered double hydroxides (LDHs) is a promising electrode material for supercapacitors (SCs) because its large specific surface area and anionic tunability. Herein, an ultrathin ternary Ni x Co 2 Al layer double hydroxides nanosheet (Ni x Co 2 Al-LDHs) grown on carbon cloth (CC) substrate by hydrothermal synthesis method is reported as a high efficiency battery-type electrode in alkaline medium. The influence of Ni on the electrochemical properties and morphology of ternary metal hydroxide is first studied. By adjusting the molar concentration of nickel, we determine that Ni 1 Co 2 Al-LDHs@CC has the best electrochemical performance. The Ni 1 Co 2 Al-LDHs@CC has a high specific capacity of 1772.5 mC cm−2 at a current density of 1 mA cm−2 and it maintains outstanding capacitive retention of 93.3% after 12,000 cycles. In addition, the obtained Ni 1 Co 2 Al-LDHs@CC//AC asymmetric supercapacitors (ASC) achieves a maximum energy density of 0.102 mWh cm−2 at power density of 0.75 mW cm−2 and keep the capacitance retention of 90.98% after 12,000 cycles to successfully light LEDs (8 mm). Detailed electrochemical kinetic analysis showed that the total capacitance of Ni 1 Co 2 Al-LDHs@CC electrode come from its effective capacitive storage mechanism. It is founded that Ni has influence on the morphology and electrochemistry of ternary metal hydroxide, which provided an effective design idea and method for improving the capacitance of ternary metal hydroxide. [ABSTRACT FROM AUTHOR]

Polyphenols are important active components of tea. Tea polyphenol oxidase (PPO) catalyzes polyphenols oxidation, hence it is vitally important to the quality and function of black tea. The enzyme was believed to be mostly deactivated during the thermal processing. Here we report the macromolecular fraction of a Chinese black tea (Camellia. sinensis var. Lapsang souchong) infusion oxidized pyrocatechol even at the enzyme's deactivation temperature. Utilizing urea-assisted extraction and ion-exchange chromatography, the PPOs and/or co-enzymes were isolated from the tea infusion and the cold water extracts of fresh tea leaves. The isolates were found to exhibit PPO activities after removing urea by dialysis. A 66.0 kDa PPO with specific activity of 1200 U/mg (K m = 6.973 mM and V max = 15.79 U/min) was purified and characterized to be a glycoprotein with isoelectric point of 4.82. The efficiency of four inhibitors against this PPO are cysteine > EDTA > sodium sulfite > ascorbic acid. The PPOs isolated from black tea infusion reserved 40–80% of activities of their aliquots from fresh tea leaves. It reveals the PPOs can survive the thermal processing of the black tea, possibly in form of PPO-polyphenol complex. Exploring the biochemistry and oxidation mechanism of tea infusion, this study may empower the future development of tea and plant-based beverages. • A Chinese black tea infusion was found to exhibit polyphenol oxidase (PPO) activity. • Three PPOs were isolated from both the tea leaves and tea infusion by chromatography. • The tea polyphenol oxidase with Mw 66.0 kDa was purified and characterized. • Heat Process-Surviving PPOs possibly exist in the forms of PPO-polyphenol complex. [ABSTRACT FROM AUTHOR]

Using a gradient band gap absorption layer to ensure high short-circuit current density is one of the key factors to prepare high-efficiency CdTe solar cells. CdSe x Te 1-x films with different selenium compositions were prepared by vacuum co-evaporation deposition technology. The effects of composition changes on the structure, morphology and properties of the films were studied. CdSe x Te 1-x films were incorporated into the CdTe solar cells with the structure of Glass/SnO 2 :F/CdS/CdSe x Te 1-x /CdTe/ZnTe:Cu/Au. The results show that the structure of CdSe x Te 1-x films is cubic when x is 0, 0.23 or 0.41, and while x is 0.61, 0.78 or 1 the structure is hexagonal. The minimum optical band gap is 1.40 eV with x = 0.41. It is found that in the long wavelength region, the cut-off edge of quantum efficiency curve depends on not only the thickness of CdSe x Te 1-x film with specific Se composition, but also the whole preparation process of solar cells. After using a 70 nm CdSe 0.41 Te 0.59 film and 70 nm ZnTe:Cu back contact buffer layer, the cut-off edge of the long wavelength region can be reduced to 1.40 eV and the short-circuit current density of the device without antireflection layer reaches up to 28.8 mA/cm2. • CdSe x Te 1-x films were prepared by vacuum co-evaporation and their structure, morphology, properties were studied. • Thin CdS, CdSe x Te 1-x and ZnTe:Cu have a greater impact on device performance. • The long wavelength cut-off edge from QE is reduced to 1.40 eV. • The J sc reaches 28.8 mA/cm2 without an anti-reflection coating. [ABSTRACT FROM AUTHOR]

Ginseng has been used as a well-known traditional Chinese medicine since ancient times. Ginsenosides as its main active constituents possess a broad scope of pharmacological properties including stimulating immune function, enhancing cardiovascular health, increasing resistance to stress, improving memory and learning, developing social functioning and mental health in normal persons, and chemotherapy. Ginsenoside Rh2 (Rh2) is one of the major bioactive ginsenosides from Panax ginseng. When applied to cancer treatment, Rh2 not only exhibits the anti-proliferation, anti-invasion, anti-metastasis, induction of cell cycle arrest, promotion of differentiation, and reversal of multi-drug resistance activities against multiple tumor cells, but also alleviates the side effects after chemotherapy or radiotherapy. In the past decades, nearly 200 studies on Rh2 in the treatment of cancer have been published, however no specific reviews have been conducted by now. So the purpose of this review is to provide a systematic summary and analysis of the anticancer effects and the potential mechanisms of Rh2 extracted from Ginseng then give a future prospects about it. In the end of this paper the metabolism and derivatives of Rh2 also have been documented. Image 1 • Nearly 200 studies on Rh2 in the treatment of cancer have been published. • No specific reviews have been conducted by now. • This is the first review to report about the anticancer effects of Rh2. • The potential anticancer mechanisms of Rh2 have been documented. • The metabolism and derivatives of Rh2 also have been introduced. [ABSTRACT FROM AUTHOR]

• Calcium and magnesium ions have concentration-dependent influences on CAA. • The absence of Ca2+/Mg2+ reduced cellular ROS and underestimated antioxidants' CAA. • Epithelial cell and hepatocytes response to Ca2+ and Mg2+ differently. • Native Ca2+/Mg2+ contents in foods and beverages can affect CAA determinations. The cellular antioxidant activity (CAA) assay is wildly used for quantifying antioxidant activities of foods and dietary supplements in vitro. Among various incubation and handling buffers used in different laboratories, the inconsistence in concentrations of ions, particularly calcium and magnesium, has somehow been neglected. We hired the Hank's balanced salt solution with or without calcium and magnesium to perform CAA assay in Caco-2 cells and HepG2 cells, evaluating the impacts of these cations. The absence of calcium and magnesium reduced intracellular ROS level and underestimated the CAA of quercetin, Trolox and catechin. The abnormally high extracellular calcium and magnesium can also produce inaccurate results. Hank's buffer is recommended to ensure the accuracy and reproducibility. It elucidates precautions must be taken on these cations' concentrations of the buffers while conducting CAA determinations on different types of cells and when comparing foods and beverages with various calcium/magnesium contents. [ABSTRACT FROM AUTHOR]

• Food-derived nanoparticles were separated from complex matrix within 5 mins by CZE. • The NPs were quantified by CZE with satisfactory precision and reproducibility. • Useful for studying other food NPs and interactions of NPs with biological samples. Food processing generates a large amount of self-assembled colloidal nanoparticles (NPs), which have defined structures and directly interact with macrophages. Their promising potential as a new source of functional NPs and a key to elucidate food-body interactions prompt the importance of the method development. This study attempts to apply capillary zone electrophoresis (CZE) in studying self-assembled nanoparticles in a real liquid food system of freshwater clam (Corbicula fluminea) soup, a popular delicacy in East Asia with proven hepatoprotective effects. The soup sample was satisfactorily separated into one nanoparticle fraction and multiple molecular fractions within five minutes by the single and rapid CZE analysis, which was of high repeatability (peak area RSD < 4%, migration time RSD < 1%) and accurate quantification with a linear area-number relationship in the range of (7.5–110) × 1011 particles/mL (R2 > 0.99). Therefore, CZE analysis can be an efficient tool for the investigation of self-assembled nanoparticles in real liquid food systems. [ABSTRACT FROM AUTHOR]

• CAT can lead to demulsification of fish oil-polysorbate submicron emulsion. • The demulsification was attributed to the enzymatic activity. • Lipid peroxidation was not the sufficient condition for the demulsification. The physicochemical and oxidative stability of oil emulsion has been one of the major challenges in food industry. Factors influencing the emulsion stability have seemingly been exhaustedly elucidated, such as temperature, pH, salts, proteins, polysaccharides and digestive enzymes. Here we report the previously unrecognized influence of catalase on emulsion stability. Submicron oil-in-water fish oil emulsion was prepared by high speed homogenization in the presence of polysorbate 80. Influence of catalase on the emulsion's stability was investigated in comparison with its deactivated version and bovine serum albumin (BSA) by visual examination, turbidity and DLS measurement and TEM observation. Catalase demulsified the emulsion instantly in a concentration-responsive manner at concentrations higher than 0.8 μmol/L, resulting a decreased turbidity, oil flocculation and precipitation of the enzyme itself. Neither BSA nor the thermally inactivated CAT caused demulsification at the same speed, indicating that CAT's demulsification effect was attributed to its enzymatic activity rather than its general protein properties. The enlargement of oil-polysorbate droplets and precipitation of CAT were confirmed by both TEM and DLS. Furthermore, CAT's demulsification effect was found irrelevant of the lipid oxidation. This insight into catalase's influences on emulsion not only sheds lights on food processing and shelf-life, nutritional value and potential biological effects, but also presents an exciting challenge to elucidate the mechanism behind. [ABSTRACT FROM AUTHOR]

The unique three-dimensional (3D) porous structure of graphite carbon nitride (g-C 3 N 4) and vanadium pentoxide (V 2 O 5) was prepared by an environmentally friendly one-step solvothermal method, and its electrochemical performance was assessed. Importantly, g-C 3 N 4 is a low cost material with excellent chemical stability, and it supports the vertical charge transfer during the charge-discharge process, which promotes electronic transmission along this direction. In addition, V 2 O 5 has good theoretical capacitance and is deemed as a potential electrode material for next-generation supercapacitors. Field emission scanning electron microscopy of the nanocomposite revealed a 3D porous morphology for g-C 3 N 4 (3D PCN) and a spherical morphology for V 2 O 5. This study estimated the viability of the graphite carbon nitride-based nanocomposite PCN@V 2 O 5 as a new catalyst in the supercapacitor (SC) anodes. A series of SC anodes with different catalyst loadings were produced. The electrochemical behavior of the SC anodes was calculated by cyclic voltammetry (CV), charge-discharge and cycling test. When test in electrochemical performance, the ratio of PCN:V 2 O 5 is lower than 1:1 and 3D PCN@V 2 O 5 exhibits a lower specific capacity, the ratio of PCN:V 2 O 5 is higher than 1:1 that most of the pores in 3D porous g-C 3 N 4 are covered that reduces the electron transport rate and results in a lower specific capacity. Overall, 3D PCN@V 2 O 5 has higher specific capacity (457 Fg-1 at 0.5 Ag-1) and better cycling performance (approximately 84% after 500 cycles). This attractive performance indicates that 3D PCN@V 2 O 5 could be used as potential electrode materials for supercapacitors. • A novel 3D porous PCN@V 2 O 5 was prepared by simple chemical precipitation method. • The 3D porous PCN@V 2 O 5 as new electrode materials exhibited great electrochemical properties. • The 3D porous PCN@V 2 O 5 products are potential supercapacitor electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

• A novel intercalated Co 3 O 4 -C/Ni 2 P 2 O 7 was prepared by simple chemical precipitation method. • The intercalated Co 3 O 4 -C/Ni 2 P 2 O 7 as new electrode materials exhibited great electrochemical properties. • Co 3 O 4 -C/Ni 2 P 2 O 7 products are ideal electrode materials for supercapacitors. Nickel pyrophosphate (Ni 2 P 2 O 7) is considered as a potential next-generation electrode material for supercapacitors. Here, we report a new type of cathode material for supercapacitors in, which consists of rhombic dodecahedron Co 3 O 4 -C growing on two-dimensional (2D) Ni 2 P 2 O 7 nanosheets. Surprisingly, Co 3 O 4 -C/Ni 2 P 2 O 7 materials exhibit bright electrochemical properties with a relatively high specific capacitance of 2537.78 Fg−1 and remarkable cyclic stability (88.5% after 3000 cycles). Therefore, the prepared Co 3 O 4 -C/Ni 2 P 2 O 7 electrode material is a significant candidate material for supercapacitors. The synthesis process is simple, low cost and environmentally friendly. Notably, Co 3 O 4 -C/Ni 2 P 2 O 7 products have excellent electrochemical properties and are candidate electrode materials for supercapacitors. The Co 3 O 4 -C/Ni 2 P 2 O 7 products have excellent electrochemical properties, which indicate the Co 3 O 4 -C/Ni 2 P 2 O 7 materials imply their promising potential applications in the energy storage. Most importantly, this work provides a scalable strategy for morphology-controlled synthesis of metal oxides by recrystallization. [ABSTRACT FROM AUTHOR]