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The rapid development of current wearable electronics motivates the promotion of energy storage devices. Supercapacitor with flexible, lightweight, highly efficient, and long cycling life is one of the potential and glittering candidates. Here, the composite film of carboxylated graphene (CG) and commercially available poly (3, 4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT:PSS) are prepared as electrodes for flexible electrochemical capacitors by ultrasonication and vacuum filtration. The CG/PEDOT:PSS films were roundly characterized by SEM, XPS, FTIR, XRD and Raman spectrometer. The as-prepared free-standing films exhibited high specific capacitance (192.7 F g-1 at 0.5 A g-1), excellent rate capability (up to 80.4% from 0.5 to 20 A g-1), and good electrochemical stability (95.5% of specific capacitance retention after 50000 cycles). Surprisingly, the post treated free-standing films by Dimethyl Formamide (DMF) shows better capacitive properties than those of the pristine electrode, such as higher specific capacitance (204.3 F g-1 at 0.5 A g-1), and ultralong-cycling stability (104.6% retention at a high current density of 20 A g-1 after 50000 cycles). It is expected that the free-standing CG/PEDOT:PSS films can be used as flexible electrodes for various wearable energy storage devices.

MAFG antisense 1 (MAFG-AS1) is recently identified as a novel lncRNA and serves as a tumor promoter in several types of human tumor. However, no prior study has been performed to evaluate the role of MAFG-AS1 in gastric cancer. In our study, we found MAFG-AS1 expression was increased in gastric cancer tissue samples compared with normal gastric mucosa tissue samples, and associated with poor overall survival in gastric cancer patients at The Cancer Genome Atlas database. Furthermore, we confirmed the clinical and prognostic significance of MAFG-AS1 in gastric cancer. We found gastric cancer tissues and cell lines had remarkably increased MAFG-AS1 expression in comparison to normal gastric mucosa tissues and normal human gastric epithelial cell line, and high MAFG-AS1 expression was positively associated with diffuse type, advanced clinical stage, extensive depth of invasion, more lymph node metastasis, and present distant metastasis in gastric cancer patients. Moreover, high MAFG-AS1 expression acted as one of the independent poor prognostic factors for overall survival in gastric cancer patients. The loss-of-function study showed knocking down MAFG-AS1 expression inhibited gastric cancer cell proliferation, migration and invasion in vitro. In conclusion, MAFG-AS1 is probable to be a valuable prognostic biomarker, and a novel potential target for gastric cancer.

Zeolite imidazolate frameworks (ZIFs), as an important part of metal–organic frameworks (MOFs), have received great attention in many application fields, such as gas adsorption, separation, and catalysis. It was found that the performances of these applications largely depend on ZIFs’ properties, such as particle size distribution, pore size, and specific surface area, which are essentially controlled by different synthetic methods. Among all the disclosed ZIF-type structures, researches on ZIF-8 are growing since it has high chemical and thermal stability and a flexible structure. Therefore, ZIF-8 was chosen as an example in this review to illustrate how synthetic factors affect the final properties of ZIF materials. We summarize the evolution process of ZIF-8 which is divided into three stages: supersaturation, nucleation, and particles. Emphasis is placed on the discussion of the influences of various factors on the formation of ZIF-8. The factors are classified into several types such as various salt ...

The hydrogenation of nitroarenes is one of the most important strategies to produce the corresponding anilines and dicyclohexylamines, both of which are the fundamental raw materials in the synthes...

Emerging clean energy technologies such as regenerative fuel cells and rechargeable metal–air batteries have attracted increasing global interest because of their high efficiency and environmental benignity, but the lack of highly active bifunctional electrocatalysts at low cost for both oxygen reduction and evolution reactions (ORR and OER) greatly hinders their commercial applications. Here, we report the multilevel architecture optimization of Co-based nanoparticles (NPs) embedded in hollow N-doped carbon polyhedra for boosting the ORR and OER, which are fabricated by a two-step pyrolysis–oxidation strategy with a Co-based MOF (ZIF-67) as precursor. The key for this strategy lies in the precise and effective control of the oxidation processes of Co NPs, which enables the synthesis of a series of Co–Co3O4-based nanoarchitectures that are embedded in hollow nitrogen-doped carbon polyhedra (HNCP), including core–shell Co/Co3O4, yolk@shell Co@Co3O4, and hollow Co3O4 NPs. Benefiting from its abundant oxygen...

Affording two semiconductors with one template in one step to construct a composite with delicate structures may endow low-cost photocatalysts with desired characteristics, i.e., high activity, stability and recyclability. Herein, novel sandwich-shelled ZnCdS/ZnO/ZnCdS cages are fabricated with “one stone”—zeolitic-imidazolate-framework-8. ZnS and ZnO are formed simultaneously in the sulfidation stage, where ZnS serves as a barrier to localize the ZnO particles filling up the voids between the ZnS layers. It could therefore be very advantageous in photocatalysis that the ZnCdS, derived from cation-exchanged ZnS, and ZnO with well-defined interfaces also have staggered band structure configurations by virtue of the fine adjustment of the composition. The Zn0.5Cd0.5S/ZnO/Zn0.5Cd0.5S cages exhibit a H2 production rate of 28.6 mmol g−1 h−1 and long-term durability, achieving the highest activities among the ZnCdS and ZnO families under noble-metal-free conditions. This remarkable performance could be ascribed to the unique morphology of the sandwich-shell and hollow interior integrating multiple vital merits for photocatalysis, including the enhanced light-harvesting ability, abundant active sites, shortened charge diffusion distances, and Z-scheme mechanism featuring preserved strong redox ability and improved charge separation and migration. This facile strategy may offer great opportunities in developing highly active metal sulfide/oxide-based photocatalysts for practical applications.

PbS colloidal quantum dots (CQDs) solar cells have already demonstrated very impressive advances in recent years due to the development of many different techniques to tailor the interface morphology and compactness in PbS CQDs thin film. Here, n-hexane, n-octane, n-heptane, isooctane and toluene or their hybrids are for the first time introduced as solvent for comparison of the dispersion of PbS CQDs. PbS CQDs solar cells with the configuration of PbS/TiO2 heterojunction are then fabricated by using different CQDs solution under ambient conditions. The performances of the PbS CQDs solar cells are found to be tuned by changing solvent and its content in the PbS CQDs solution. The best device could show a power conversion efficiency (PCE) of 7.64% under AM 1.5 G illumination at 100 mW cm−2 in a n-octane/isooctane (95%/5% v/v) hybrid solvent scheme, which shows a ~15% improvement compared to the control devices. These results offer important insight into the solvent engineering of high-performance PbS CQDs solar cells.

Ultrafine hematite powder was reduced to produce ultrafine iron powder in a 50%Ar-50%H-2 atmosphere at 450-550 degrees C in a fluidized bed reactor. The ultrafine hematite powder shows the typical agglomerating fluidization behavior with large agglomerates fluidized at the bottom of the bed and small agglomerates fluidized at the upper part of the bed. It was found that defluidization occurred even at the low temperature of 450 degrees C with low metallization rate. Defluidization was attributed mainly to the sintering of the newly formed iron particles. Granuation was employed to improve the fluidization quality and to tackle the defluidization problem, where granules fluidized like a Geldart's group A powder. Granulation was found to effectively reduce defluidization during reduction, without however sacrificing reduction speed. The as-reduced iron powders from both the ultrafine and the granulated hematite exhibited excellent sintering activity, that is, fast sintering at temperature of as low as similar to 580 degrees C, which is much superior as compared to that of nano/ultrafine iron powders made by other processes. (C) 2012 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Solution-processed CdTe nanocrystals (NCs) photovoltaic devices have many advantages, both in commercial manufacture and daily operation, due to the low-cost fabrication process, which becomes a competitive candidate for next-generation solar cells. All solution-processed CdTe NCs solar cells were first reported in 2005. In recent years, they have increased over four-fold in power conversion efficiency. The latest devices achieve AM 1.5 G power conversion efficiency up to 12.0%, values comparable to those of commercial thin film CdTe/CdS solar cells fabricated by the close-space sublimation (CSS) method. Here we review the progress and prospects in this field, focusing on new insights into CdTe NCs synthesized, device fabrication, NC solar cell operation, and how these findings give guidance on optimizing solar cell performance.

Co-Ni bimetallic aerogel catalysts with various Co/Ni ratios were synthesized by the sol gel method followed by the supercritical drying process. The catalysts were characterized by XRD, H-2-TPR, HRTEM, BET, TG and FESEM. It showed that the Co/Ni ratio influenced the micro-structure of the Co-Ni bimetallic aerogel catalysts. The formation of homogeneous metal alloy on the bimetallic catalysts was observed after the reduction. In addition, catalysts with higher Co/Ni ratios showed smaller active metal particle sizes. The activities of the aerogel catalysts in terms of CH4 conversion were found to be in the order of 5Co5Ni approximate to 3Co7Ni > 7Co3Ni > 10Ni >> 10Co. 5Co5Ni exhibited the highest CH4 conversion in methane Oxy-CO2 reforming, which is 16% and 55% greater than those of 10Ni and 10Co, respectively. The difference between the catalytic performances could mainly be attributed to the combined effect of the kinetics, the geometric and the SMSI effects. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

This work reports the first synthesis of CuO-CeO2 binary oxides with a plate-like morphology by a solvothermal method. The as-prepared CuO-CeO2 nanoplates calcined at 400 degrees C were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectrum, and tested for catalytic oxidation of dilute benzene in air. Various structural characterizations showed that large amounts of copper species were exposed oil the CuO-CeO2 nanoplate surface. The effect of the synthesis conditions on the structure of the product, as well as the growth process of the nanoplates, has been studied and discussed. The CuO-CeO2 nanoplates exhibited an excellent catalytic activity for benzene oxidation despite its relatively low surface area and could catalyze the complete oxidation of benzene at a temperature as low as 240 degrees C. (C) 2009 Elsevier Ltd. All rights reserved.

Cu(x)Ce(1-x)C(y) (x = 0.06, 0.13, and 0.23) were prepared by a solution combustion route using glycine as the fuel and tested for the catalytic combustion of dilute acetone in air. The structural characteristics of the catalysts were investigated by specific surface area, X-ray diffraction (XRD). scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and temperature-programmed reduction (TPR) techniques. The results reveal that the state of the CuO depends on the Cu/Ce molar ratio in the catalyst, which strongly influences the redox behavior and the catalytic activity of the sample. Among the three Catalysts, Cu(0.13)Ce(0.87)O(y) was found to be the most active in the catalytic Combustion of acetone. The pulse reaction of pure acetone in the absence of O(2) Over the Cu(0.13)Ce(0.87)O(y) catalyst indicated the participation of lattice oxygen from the catalyst in the acetone combustion. Furthermore, the effect of the acetone concentration and the gas hourly space velocity (GHSV) on the catalytic behavior of the catalyst was examined. The stability of the Cu(0.13)Ce(0.87)O(y) catalyst for acetone combustion was also investigated and an obvious deactivation was observed under the reactant stream for 35 h at 260 degrees C. XRD analysis of the deactivated catalyst showed that the formation of bulk CuO was responsible for the deactivation of the catalyst. (C) 2009 Elsevier B.V. All rights reserved.

The characteristics of highway service district sewage were investigated. High oil and grease contents were detected. A novel high efficiency oil isolation/coalesce apparatus(NOICA) was used to treat this type of sewage. Different coalesec materials and operational conditions were examined. Quartz sand was preferred to cinder and coal dust. Hydraulic loading was found to be the variable that affected the oil removal efficiency significantly. The optimum hydraulic loading should not higher than 21m3/m2.h, depending on swage characteristics. The removal efficiency of oil and grease exceeded 70% for most sewage tested. The experimental results also show that the temperature and pH also can affect the oil removal efficiency, and the optimum temperature and pH were 30degC,and 5.00-7.00 respectively.