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A ship-in-a-bottle architecture on carbon nanotube yarn-based supercapacitor is prepared, in which transition metal hydroxide nanoparticles are confined in metal–organic frameworks anchored on carbon nanotubes and exhibits ultrahigh structural and electrochemical stability.

Yarn-shaped supercapacitors (YSSCs) based on aqueous electrolyte exhibit a relatively low voltage output due to the low decomposition voltage of water (∼1.23 V). Applying organic-based electrolyte or connecting YSSCs in series with metal-wire involves issues such as safety, air stability, contact resistance and so on. Herein, these issues are addressed by designing tandem YSSCs (T-YSSCs) where several YSSCs are interconnected in series on a single poly(tetrafluoroethylene) (PTFE) filament using a simple dip-coating method. The resultant T-YSSCs display a high voltage density of 72 V m−1, robust areal specific capacitance of 475.6 mF cm−2, high electrochemical stability (95.2% retention after 10 000 cycles) and a tensile strength of 125.4 MPa. Moreover, they show negligible contact resistance compared to that of metal wires interconnected ones, because of the diminished built-in Schottky barrier between interconnected electrodes. An energy storage fabric (ESF) with adjustable voltage and current demonstrates good potential for on-body practical applications because it is well adapted to be worn on human body to power an electronic watch, a pedometer and so on.

Hydroboration of carbon dioxide (CO2) catalysed by bis(phosphinite) (POCOP) pincer nickel complexes is among the most efficient homogeneous processes for the reduction of CO2 to the methanol level. Although both POCOP pincer nickel hydride and thiolate complexes are effective catalysts, the latter is far more effective under the same conditions. The mechanism for nickel hydride complexes catalysed reactions is well-established. However, that for nickel thiolate complex catalysed reactions remains elusive. In this work, the mechanism for the reduction of CO2 catalysed by POCOP pincer nickel thiolate complexes was investigated using density functional theory. The calculated results indicated that the reaction occurs via a concerted catalytic process involving two active species and the hydride is transferred by a shuttle species. Specifically, the reaction proceeds through four cycles: formation of two active species (cycle I) followed by further reaction of these two species to form a hydride transfer shuttle which is responsible for hydride transfers CO2→HCOOBcat (cycle II), HCOOBcat→CH2O (cycle III) and CH2O→catBOCH3 (cycle IV). The calculated mechanism is in good agreement with the experimental observation that the reaction is exothermic with simultaneous HBcat degradation.

It has been reported that either the boryl formate (HCOOBR2), bis(boryl)acetal (R2BOCH2OBR2), or methoxy borane (R2BOCH3) product of CO2 reduction is selectively afforded adopting the nickel (Ni) pincer catalyst by changing the properties of borane reductants. To obtain an insight into the influence of borane reductants on the selectivity of hydroboration of CO2 catalyzed by (tBuPCP)NiH, a density functional theory (DFT) computational study is performed with three different boranes (HBcat (catecholborane), 9-BBN (9-borabicyclo [3.3.1] nonane), and HBpin (pinacolborane)). The detailed formation and conversion of four-electron product R2BOCH2OBR2 were considered for the first time, combining with the three sequential catalytic cycle mechanism, and the calculated results demonstrate that the distinctions of the electronic process in some key intermediates and transition states lead to the selectivity on products for different borane reductants.

Element doping is an effective strategy to enhance the selectivity of electrochemical carbon dioxide reduction. In this work, a dendritic core-shell In-doped Cu@Cu2O catalyst is prepared by co-electrodeposition method on carbon fiber paper for selective electroreduction of CO2 to CO. Faradaic efficiency of producing CO over this dendritic In-doped Cu@Cu2O reaches 87.6 ± 2.2% with total current density of 11.1 ± 0.85 mA cm−2 at −0.8 V vs RHE, which outperforms most of the reported Cu-based electrocatalysts. The excellent performance is mainly derived from charge re-distribution and the enhanced intrinsic activity due to the formation of In-doped Cu2O layer. Meanwhile, the Cu+/Cu0 can be adjusted by tailoring the doped-In content. The relatively high ECSA and small charge transfer resistance are also conducive to improve the selectivity and activity. The oxyphilic In metal incorporated into the copper lattice can well stabilize the intermediate *COOH through enhancing interaction with O-ends of *COOH. This work provides a facile approach and a deep insight on design and synthesis of high efficiency hybrid electrocatalysts.

To develop earth-abundant and cost-effective catalysts for overall water splitting is still a major challenge. Herein, a unique “raisins-on-bread” Ni–S–P electrocatalyst with NiS and Ni2P nanoparticles embedded in amorphous Ni(OH)2 nanosheets is fabricated on Ni foam by a facile and controllable electrodeposition approach. It only requires an overpotential of 120 mV for HER and 219 mV for OER to reach the current density of 10 mA cm−2 in 1 M KOH solution. Employed as the anode and cathode, it demonstrates extraordinary electrocatalytic overall water splitting activity (cell voltage of only 1.58 V @ 10 mA cm−2) and ultra-stability (160 h @ 10 mA cm−2 or 120 h @50 mA cm−2) in alkaline media. The synergetic electronic interactions, enhanced mass and charge transfers at the heterointerfaces facilitate HER and OER processes. Combined with a silicon PV cell, this Ni–S–P bifunctional catalyst also exhibits highly efficient solar-driven water splitting with a solar-to-hydrogen conversion efficiency of 12.5%.

In this perspective, we present computational progress in the reduction of carbonyl compounds using boron reducing agents, such as L·BH3, HBcat, HBpin, and 9-BBN. For the catalytic reduction reactions, establishing a catalytic mechanism will provide an important theoretical basis for the improvement of a more efficient combination of reducing agents and catalysts. Current computational studies reveal that the mechanisms of reactions are different due to the various combinations of electrophilic boron reducing agents and catalysts (transition-metal catalyst, main group metal catalysts, and metal-free frustrated Lewis pair). We discuss the role of boron reducing agents on the efficiency of reactions and believe that possible Lewis acid–base interaction between Bδ+, Mδ+ and Oδ−, Hδ− existing in boron reducing agent, unsaturated substances, and catalyst should be considered fully. A tentative outlook on future opportunities of this research field is proposed.

The experiments on microwave pyrolysis of soybean straw are studied to produce hydrogen-rich gas under CO2 atmosphere in this paper. The microwave power has an important effect on the temperature. ...

A stable solid acid catalyst, SCPR140-1, was synthesized from chloromethyl polystyrene resin (CPR) and used for catalytic pretreatment of corncob in aqueous solution. Under the optimized pretreatment condition, 73.07 % of xylose was directly obtained, and the enzymatic digestibility of treated residue reached up to 94.65 %, indicating that the SCPR140-1 had high selectivity for xylose production and effectively deconstructed the structure of corncob. The -CH2 Cl group of CPR was substituted by -SO3 H through the sulfonation, and the -SO3 H was stably bound on the catalyst during the pretreatment process. Compared with other similar reports, the SCPR140-1 was not only synthesized through a simpler process but also had a more stable catalytic activity during multiple recycling runs.

Developing highly active and stable electrocatalysts for acidic oxygen evolution reaction is still a great challenge. Herein, we developed a novel self-supported amorphous IrOx catalyst (IrOx/Ti) encapsulated with a small number of crystalline nanoparticles for efficient acidic OER. The resulting IrOx-50-AC/Ti electrode exhibits a superior OER performance with an overpotential of 250 mV at 10 mA cm−2 and Tafel slope of 50.4 mV dec−1 in 0.1 M HClO4. High contents of IrIII species and surface hydroxide groups, hierarchically porous structure and high defective density contribute to boost the OER activity. Importantly, the amorphous IrOx-50-AC/Ti also demonstrates a super long-term durability for 190 h due to the strong interaction between IrOx film and Ti. The unique amorphous-crystalline structure also enhances the stability and the activity by promoting the synergy between amorphous phase and crystalline phase. This work provides some valuable insights on developing efficient Ir-based catalysts for acidic water splitting.

Disheveled-Axin domain containing 1 (DIXDC1) is involved in the development and progression of multiple cancers. However, the function significance of DIXDC1 in prostate cancer remains unclear. In this study, we investigated the function of DIXDC1 in prostate cancer and the regulation of DIXDC1 by microRNAs (miRNAs). We found that DIXDC1 was highly expressed in prostate cancer cells. Knockdown of DIXDC1 by small interfering RNAs markedly suppressed proliferation, invasion and Wnt signaling in prostate cancer cells. DIXDC1 was identified as a target gene of miR-1271 by bioinformatics analysis, dual-luciferase reporter assay, real-time quantitative polymerase chain reaction and Western blot analysis. Furthermore, DIXDC1 expression was inversely correlated with miR-1271 expression in prostate cancer tissues. The overexpression of miR-1271 significantly inhibited proliferation, invasion and Wnt signaling in prostate cancer cells. However, the inhibition of miR-1271 exhibits the opposite effects. Moreover, the overexpression of DIXDC1 significantly reversed the inhibitory effects of miR-1271 overexpression. Taken together, our results suggest that DIXDC1 plays an important role in regulating prostate cancer cell proliferation and invasion. Targeting DIXDC1 by miR-1271 may be a promising therapeutic strategy for prostate cancer.

Bio-oil model compounds dry (CO2) reforming for hydrogen production over Ni/Al2O3 catalyst is presented in this paper. The research investigates the effects of reaction conditions such as temperature, weight hourly space velocity of the aqueous phase (WHSV), CO2 to carbon in bio-oil ratio (CO2/Bio-oil) on hydrogen yield and products distribution. And also study the coke formation rates versus different reaction temperature and different CO2/Bio-oil ratio. Meanwhile analyze the types of carbon deposited on Ni/Al2O3 catalyst. The experimental results show that, the optimum reaction temperature is 700 °C, CO2/Bio-oil is 0.75, WHSV is 0.9 h−1, under these conditions, hydrogen yield and bio-oil model compounds conversion reach 88.19% and 96.87% respectively, the molar ratio of H2/CO reaches 1.08. The coke formation rate exists a maximum at 600 °C, higher temperature (>600 °C) and higher CO2/Bio-oil (>0.75) are all good for carbon elimination of dry reforming. The forms of carbon deposit on Ni/Al2O3 catalyst are mainly filamentous carbon and graphitic carbon.

To develop robust and highly active bifunctional electrocatalysts for electrochemical water splitting in acidic media is still a great challenge for proton exchange membrane (PEM) electrolyzer. Herein, a self-assembled IrCox nanorings (NRs) with bracelet-like architecture is fabricated as a bifunctional high-efficient overall water splitting electrocatalyst by a facile, controllable and surfactant-free strategy. The unique nanoring architecture enriches in abundant homointerface and strong synergistic electronic interaction between Ir and Co. The optimized IrCo0.14 NRs exhibits remarkable electrocatalytic performance with a low overpotential of 16 mV for hydrogen evolution reaction (HER) and 278 mV for oxygen evolution reaction (OER) at 10 mA cm−2 in 0.1 M HClO4, respectively, significantly outperforming the commercial Pt/C, Ir/C and reported Ir-based catalysts. As both anode and cathode, a cell voltage of only 1.53 V to reach 10 mA cm−2 is obtained for overall water splitting and no obvious activity loses after a long-term electrolysis for 14 h. Combined with a PV cell, this catalyst also shows excellent water splitting performance with a solar-to-hydrogen conversion efficiency of 12.8%. This work provides further insights on designing promising and efficient bifunctional electrocatalysts for clean energy electrochemical conversion in the future.

Photo-induced conductivity modulation of stimuli-responsive materials is of great importance from the viewpoint of fundamental research and technology. In this work, 5 new kinds of azobenzene-based photo-responsive ionic liquids were synthesized and characterized, and UV/vis light modulation of their conductivity was investigated in an aqueous solution. The factors affecting the conductivity modulation of the photo-responsive fluids, such as photo-isomerization efficiency, photo-regulation aggregation, concentration and chemical structure of the ionic liquids, were examined systematically. It was found that the conductivity of the ionic liquids in water exhibited a significant increase upon UV light irradiation and the ionic liquids with a shorter alkyl spacer in the cation showed a more remarkable photo-induced conductivity enhancement with a maximum increase of 150%. In addition, the solution conductivity was restored (or very close) to the initial value upon an alternative irradiation with visible light. Thus, the solution conductivity can be modulated using alternative irradiation with UV and visible light. Although the reversible photo-isomerization of the azobenzene group under UV/vis irradiation is the origin of the conductivity modulation, the photo-regulated aggregation of the ionic liquid in water is indispensable for the maximum degree of conductivity modulation because UV irradiation can weaken, even break the aggregated cis-isomers of the ionic liquids in an aqueous solution.

In the present work, hydrolysis of sweet sorghum bagasse residue using dilute acid was investigated. The sweet sorghum bagasse residue was from pretreatment. Process parameters investigated include reactor temperature, reaction time, and acid concentration in order to find suitable conditions for hydrolysis of the cellulose fraction. The effects of dilute acid hydrolysis were assessed by glucose yield and decomposition products concentration. The highest yield of glucose, 70.10%, was found at the temperature of 170°C, acid concentration of 1.0% (w/w), and a reaction time of 10 min. Meanwhile, 0.99 g/L of acetic acid, 0.22 g/L of furfural, 0.73 g/L of hydro-xymethyl furfural, and 1.60 g/L of levulinic acid were obtained under these conditions, which concluded that the decomposition of glucose was slight and confirmed the selectivity of this dilute acid hydrolysis of the sweet sorghum bagasse residue. The present work aims to take full advantage of the sweet sorghum bagasse residue and obtain glucose soluti...

Hydrolysis of hemicellulose and disruption of cellulose during pretreatment process are conducive to the following cellulase hydrolysis performance. In this work, bagasse pith was first pretreated by 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) solution containing 0–1.2% hydrochloric acid (HCl) and 30% water. The water (30%) added into the acidic ionic liquid (IL) solutions led to an increase in the biomass loading up to a biomass/IL solutions ratio of 1:10 (wt.%). Hemicellulose was hydrolyzed to reducing sugars by HCl and cellulose was dissolved by [BMIM]Cl. In this process, 76.9% of hemicellulose conversion and 95% of cellulose recovery were obtained. The pretreated bagasse pith was then followed by hydrolysis with commercially available enzymes. The effects of pretreatment temperature, reaction time and acid concentration on cellulase hydrolysis of pretreated bagasse pith were investigated. Pretreatment of bagasse pith with [BMIM]Cl solutions containing 1.0% HCl at 120 °C for 30 min resulted in the glucose concentration of 92.3 g/l and yield of 94.5% after 72 h of cellulase hydrolysis. The maximum total reducing sugars yield reached to 89.9% after pretreatment and cellulase hydrolysis.

To explore the feasibility of using herbal medicine waste (HMW) as solid fuel, HMW was torrefied under different temperatures and atmospheres. The physicochemical properties and combustion behaviors of the torrefied HMW were investigated. Temperature was found to be the most influential factor affecting the torrefaction. Torrefaction improved the hydrophobicity of HMW and decreased the equilibrated moisture uptake from 24.48(0.083) % to 15.22(0.054) %. The HMW samples torrefied under different conditions are easy to ignite. The comprehensive combustibility index (S) of the torrefied HMW increased by 3–5 folds compared to that of the raw sample. In general, the HMW torrefied under lower temperatures and under CO2 and O2 have better flammability. The present results revealed that the torrefied HMW exhibited good combustion characteristics and can thus be used for solid fuel production, such as fuels for co-combustion or raw materials for pelletization.

MicroRNAs (miRNAs) play a pivotal role in cancer progression and development, representing novel therapeutic tools for cancer therapy. Forkhead box Q1 (FOXQ1) functions as an oncogene in various cancer types. However, the functional significance of FOXQ1 in cervical cancer remains unknown. In this study, we investigated the biological function of FOXQ1 in cervical cancer and tested whether or not FOXQ1 can be targeted and regulated by specific miRNAs. We found that FOXQ1 was highly expressed in cervical cancer cell lines. Knockdown of FOXQ1 by small interfering RNA (siRNA) significantly suppressed the proliferation and epithelial-mesenchymal transition (EMT) of cervical cancer cells. FOXQ1 was predicted as a target gene of microRNA-506 (miR-506), and this prediction was validated by dual-luciferase reporter assay. Quantitative real-time PCR and western blot analyses demonstrated that mRNA and protein expression was negatively regulated by miR-506. The expression of miR-506 was downregulated in cervical cancer tissues, and miR-506 expression was inversely correlated with FOXQ1 expression in cervical cancer. The overexpression of miR-506 dramatically suppressed the proliferation and EMT of cervical cancer cells that mimicked the suppression of FOXO1 siRNA. Furthermore, the restoration of FOXQ1 expression significantly reversed the inhibitory effect of miR-506. Overall, our study demonstrated that miR-506 inhibited the proliferation and EMT of cervical cancer cells by targeting FOXQ1 and provided evidence that the miR-506/FOXQ1 axis plays an important role in the pathogenesis of cervical cancer, representing potential molecular targets for the development of anticancer agents for cervical cancer treatment.

In the present study, the effects of Mg-Nd-Zn-Zr (JDBM), brushite (CaHPO4·2H2O)-coated JDBM (C-JDBM), AZ31, WE43, pure magnesium (Mg) and Ti alloy (TC4) on rabbit chondrocytes were investigated in vitro. Adhesion experiments revealed the satisfactory morphology of chondrocytes on the surface of all samples. An indirect cytotoxicity test using MTT assay revealed that C-JDBM and TC4 exhibited results similar to those of the negative control, better than those obtained with JDBM, AZ31, WE43 and pure Mg (p0.05). The results of indirect cell cytotoxicity and proliferation assays, as well as those of apoptosis assay, glycosaminoglycan (GAG) quantification, assessment of collagen II (Col II) levels and RT-qPCR revealed a similar a trend as was observed with MTT assay. These findings suggested that the JDBM alloy was highly biocompatible with chondrocytes in vitro, yielding results similar to those of AZ31, WE43 and pure Mg. Furthermore, CaHPO4·2H2O coating significantly improved the biocompatibility of this alloy.

Owing to the complexity of structural characteristics, it is difficult to accurately model the super shallow large-span tunnel. In this study, aiming at an actual tunnel, we investigate the refined modelling of super shallow large-span tunnel. First, the three-dimension finite element model of this actual tunnel is established considering the disturbance of the surrounding rock, construction sequence and the change of stress state of structure during the construction process. Second, with the generated finite element model, the variation rules of the crown displacement and the initial lining stress are analysed numerically. Finally, the results of the numerical simulation are compared with the measured. The results show that the established model can simulate the construction excavation accurately.