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Urea electrolysis is a promising approach to produce hydrogen while simultaneously purifying urea-rich wastewater. In practice, it is highly desirable but still challenging, through the structure construction strategy, to implement a method with controllable synthesis of ultra-thin nanosheet arrays with rich interfaces, and then apply them into the catalysis operations of hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). In this work, the bifunctional electrocatalyst Ni

Molybdenum disulfide (MoS

Lead-acid batteries are a reliable and cost-effective uninterrupted power supply for cars, wheelchairs, and others. Recycling the spent lead-acid batteries has increased cost and could be a serious pollution issue after extensive use. It is important to exploit new-generation application to increase their value. In this article, we used a simple method for recycling spent lead-acid batteries for a useful lead iodide resource with a high purity of over 99% and a recycling yield of 93.1% and then fabricated multifunctional FAPbI3 perovskite diodes using recycled lead iodide (PbI2). The cost of recycled PbI2 based on lab-grade chemicals is estimated to be only 13.6% that of lab-grade PbI2, which undoubtedly greatly reduces the preparation cost of devices in the lab. The external quantum efficiencies of our perovskite diodes prepared with commercial and recycled PbI2 are 19.0 and 18.7%, respectively, which shows that the performance of the device prepared from recycled PbI2 is comparable to that of commercial lab-grade PbI2. Based on the expense of industrial-grade chemicals, the cost of recycled PbI2 is extrapolated to be 70.2% that of industrial-grade PbI2. Therefore, it can not only offer an approach to recycle hazardous solid waste but also save manufacturing cost of new-generation photoelectric devices, leading to earning additional value for lead waste.

This study evaluated changes in fatty acids from sera, red blood cells and colonic biopsies from a phase Ib clinical trial of personalized ω-3 fatty acid dosing in 47 healthy volunteers. The trial aimed to reduce colonic prostaglandin E(2) (PGE(2)), a pro-inflammatory product of arachidonic acid (AA) oxidation. The personalized doses ranged 2-10 grams/day (54% eicosapentaenoic acid, EPA, 24% other ω-3 fatty acids). In colon, increases in ω-3 highly unsaturated fatty acids (HUFA) and EPA:AA ratios each were correlated with decreases in PGE(2). Changes in either colonic EPA:AA ratios or ω-3 HUFA were significantly correlated with changes in the same fatty acid measures in red blood cells or serum. The only blood-based measure significantly correlated with changes in colonic PGE(2) was change in red blood cell ω-3 HUFA (ρ = − 0.39), and the increase in red blood cell ω-3 HUFA was significantly greater in participants who had at least a median reduction in colonic PGE(2) versus those who did not. In summary, fatty acid changes in blood did reflect fatty acid changes in the colon, but additional factors will be needed for optimizing dosing models that seek to predict the anti-inflammatory effects of ω-3 fatty acids on the colon.

Advanced efficient energy conversion technology using clean alternative fuel contributes to the alleviation of the energy crisis and environmental deterioration. In this situation, a novel methanol utilization technology for power generation based on hybrid fuel cell system is proposed in this work. The hybrid system consists of a solid oxide fuel cell (SOFC), a gas processing unit (GP) and a proton exchange membrane fuel cell (PEMFC). Thermodynamic analysis of the system shows that the energy conversion efficiency and exergy efficiency are both higher than the previously reported standalone or hybrid energy systems using methanol as fuel, which are 66.2% and 54.2% respectively. Besides, no recirculation ratio of anode off-gas and moderate fuel utilization of about 0.5 are suggested for the SOFC component to balance the power distribution and improve the efficiency. Afterwards, this hybrid fuel cell system is also investigated from thermo-economic and techno-economic perspectives. Take Northwest China as a case, the 1 MWe methanol-fed power plant has a specific electric energy cost of 0.5594 CNY/kWh, much lower than the methanol steam reforming-PEMFC power plant (2.4 CNY/kWh). At the same time, the sensitivity analyses reveal that the cost of the hybrid power system is not sensitive to the market price fluctuation. With financial subsidies for existing renewable power plants, the payback period can be shortened to 1.4 year and the annual return on investment is about 3.58%. These results reveal that this two-stage fuel cell hybrid system is a kind of efficient and economically methanol to power conversion technology, especially for small power scale. © 2021 Elsevier Ltd

Thermal energy storage system is of great significance for the concentrated solar power system to keep the balance between power generation and demand. Metal hydride based thermal energy storage system is regarded as a promising method due to its good reversibility, low cost, and no by-product. Multi-phase heat exchange has much higher heat transfer coefficient than single-phase fluid heat exchange, thus facilitating the steam generation. In this study, a two-dimensional model of the metal hydride reactor using multi-phase heat exchange is proposed to estimate the performance and its feasibility of application in the concentrated solar power system. The results show that the velocity of the heat transfer fluid should match well with the thermal conductivity of the metal hydride bed to maintain the heat flux at a relatively constant value. The match of thermal conductivity of 3 or 5 W/(m·K) and fluid velocity of 0.0050 m/s results in the heat flux up to about 19 kW/m2, which is increased by 3 orders of magnitude than single-phase heat exchange. In the thermal energy storage system, the reheating cycle is recommended to improve the utilization of the thermal energy. The efficiency of the system could be improved from 18.4% to 30.8% using the reheating cycle. The increased efficiency is comparable to the previously reported efficiency of 39.2%. Besides, the operation strategy of raising the steam temperature by increasing the hydrogen pressure or the superheater temperature is suggested for the system to obtain higher efficiency.

The status of FOXP3 and its isoforms in hepatocellular carcinoma (HCC) is unclear. We aimed to investigate the expression and function of FOXP3 and its isoforms in HCC. The study was performed on 84 HCC patients, HCC cell lines and a mouse tumor model. The levels of FOXP3 and its isoforms were determined by nested PCR, quantitative real-time PCR and immunohistochemistry (IHC) staining. The correlation between their levels and clinicopathologic characteristics was analyzed. The full length of FOXP3 (FOXP3) and exon 3-deleted FOXP3 (FOXP3Δ3) were found to be the major isoforms in HCC. The levels of FOXP3Δ3 mRNA and protein in HCC tumor samples were not significantly different from their adjacent normal tissues. The high expression of FOXP3 protein in HCC patients showed a good overall survival. The overexpression of FOXP3 significantly reduced tumor cell proliferation, migration and invasion. The immunofluorescence result indicated that FOXP3 needed to be translocated into the nucleus to exert its inhibitory function. The luciferase assay demonstrated that FOXP3 could be synergistic with Smad2/3/4 to inhibit the oncogene c-Myc. The co-immunoprecipitation results further revealed that FOXP3 could interact with Smad2/3/4. The chromatin immunoprecipitation (ChIP) assay showed that both FOXP3 and Smad2/3/4 bound the promoter of the c-Myc to inhibit it. The in vivo mouse tumor model study confirmed the inhibitory effect of FOXP3. Collectively, the expression of tumor FOXP3 can inhibit the growth of HCC via suppressing c-Myc directly or indirectly via interacting with Smad2/3/4. Therefore, FOXP3 is a tumor suppressor in HCC.

N-doped carbon-encapsulated transition metal selenides (TMSs) have garnered increasing attention as promising electrocatalysts for hydrogen evolution reaction (HER). Accurately regulating the electronic structure of these nanohybrids to reveal the underlying mechanism for enhanced HER performances is still challenging and thus requires deep excavation. Herein, a series of pomegranate-like Ni

Background The status of FOXP3 and its isoforms in hepatocellular carcinoma (HCC) is unclear. We aimed to investigate the expression and function of FOXP3 and its isoforms in HCC. Methods The study was performed on 84 HCC patients, HCC cell lines and a mouse tumor model. The levels of FOXP3 and its isoforms were determined by nested PCR, quantitative real-time PCR and immunohistochemistry (IHC) staining. The correlation between their levels and clinicopathologic characteristics was analyzed. Results The full length of FOXP3 (FOXP3) and exon 3-deleted FOXP3 (FOXP3Δ3) were found to be the major isoforms in HCC. The levels of FOXP3Δ3 mRNA and protein in HCC tumor samples were not significantly different from their adjacent normal tissues. The high expression of FOXP3 protein in HCC patients showed a good overall survival. The overexpression of FOXP3 significantly reduced tumor cell proliferation, migration and invasion. The immunofluorescence result indicated that FOXP3 needed to be translocated into the nucleus to exert its inhibitory function. The luciferase assay demonstrated that FOXP3 could be synergistic with Smad2/3/4 to inhibit the oncogene c-Myc. The co-immunoprecipitation results further revealed that FOXP3 could interact with Smad2/3/4. The chromatin immunoprecipitation (ChIP) assay showed that both FOXP3 and Smad2/3/4 bound the promoter of the c-Myc to inhibit it. The in vivo mouse tumor model study confirmed the inhibitory effect of FOXP3. Conclusion Collectively, the expression of tumor FOXP3 can inhibit the growth of HCC via suppressing c-Myc directly or indirectly via interacting with Smad2/3/4. Therefore, FOXP3 is a tumor suppressor in HCC.

The finite element method (FEM) models of expanded polystyrene (EPS) concrete were established to study the relationships among dynamic damage, energy absorption and efficiency of buffering materials with varied flexible aggregate contents and impact speeds based on the existing split Hopkinson pressure bar (SHPB) experiments. Applied material indexes including damage degrees, crack rates and energy absorption capacities, and the dynamic responses of EPS concrete under impact loading were investigated. The results show that the failure types of these materials evolve from quasi-brittle destruction to flow-plastic destruction, the damage degree of EPS concrete increases with the enhancement of flexible aggregate content, and the peak of crack rate exists around the extreme point of shock velocities. The energy-absorption efficiency of EPS concrete increases nonlinearly when the EPS beads increase and the shock speed enhances, respectively.

Herein, we report a simple method for the preparation of cross-linked polymer of intrinsic microporosity (PIM-1)/Materials Institute Lavoisier chromium (III) terephthalate [MIL-101(Cr)] monoliths which involves direct impregnation of PIM-1 with MIL-101(Cr) powder by physical mixing in tetrachloroethane solvent. This procedure yields monoliths with high metal–organic framework (MOF) loading weight percentages of up to 80 wt% of MIL-101 powder with little loss of composite mechanical strength. From the nitrogen adsorption isotherms, it was observed that the PIM-1/80 wt% MIL-101(Cr) had good retention of MOF filler surface area and accessibility of its micropores with nearly no pore blocking effects. The hydrogen adsorption was also not far from the estimated hydrogen uptake capacity based on the MIL-101 weight percentage estimation. As a consequence of the highly porous nature of the hybrid material, PIM-1/MIL-101(Cr) composite has been considered as a promising material for inclusion in hybrid hydrogen storage cylinders. Moreover, these composites provided better handling compared to the crystalline powder MOFs without compromising the properties of MOF.

Hybrids of graphite nanosheet-supported CoMoS4 (GN-CoMoS4) were synthesized through a hydrothermal method. The CoMoS4 nanoparticles are uniformly distributed on the graphite nanosheets, leading to large specific surface area and good electrical conductivity. The GN-CoMoS4 hybrids were systematically studied for electrode materials of supercapacitors. Due to the amorphous characteristic of CoMoS4, which can supply more transportation channels for ion diffusion, together with the large specific surface area and excellent conductivity of GN, the as-prepared hybrid electrode material exhibited a high specific capacitance of 774 F g−1 at the current density of 1 A g−1 and an excellent cyclic stability (94.49% of its initial specific capacitance retained after 6000 cycles at a current density of 8 A g−1). An all-solid-state asymmetric supercapacitor was fabricated using GN-CoMoS4 as positive electrode and porous active carbon (AC) as negative electrode, which exhibited a highest energy density of 42.85 W h kg−1 at 900 W kg−1 and excellent cycling stability (93.2% retention after 8000 cycles). The results demonstrate that the GN-CoMoS4 hybrids are promising candidate for the electrode materials in high-performance supercapacitors because of the well-designed microstructure.

Pallets play an important role in logistics. It is well known that pallet rental is beneficial to both pallet users and society, and the pallet rental industry is very large nowadays. A non-oriented super-efficiency integer-valued DEA (data envelopment analysis) model for the performance evaluation of pallet rental companies is presented. The method differs from traditional models in that (1) it can be used to accurately estimate the performance of efficient pallet rental companies with integer-valued and real-valued variables; (2) it is an alternative approach to providing numerical super-efficiency scores for efficient pallet rental companies when input-oriented or output-oriented VRS (variable returns to scale) super-efficiency models are infeasible for them. A case study of nine pallet rental companies proves the advantages of the proposed model, and it shows that the efficiency gap among pallet rental companies is very large. Based on the results, some suggestions on the development of the pallet rental industry are proposed. The methodology and results would provide valuable contributions to the decision-making processes of both pallet rental companies and their customers.

In this work, the density and electronic structures of the metal active sites in NiCo2O4 nanorod arrays were concurrently tuned by controlling the sample’s exposure time in a phosphorization process. The results showed that both the density and electronic structure of the active adsorption sites played a key role towards the catalytic activity for water splitting to produce hydrogen. The optimal catalyst exhibited 81 mV overpotential for hydrogen evolution reaction (HER) at 10 mA cm−2 and 313 mV overpotential towards oxygen evolution reaction at 50 mA cm−2. The assembled electrode delivered a current density of 50 mA cm−2 at 1.694 V in a fully functional water electrolyzer. The further results of theoretical density functional theory calculations revealed the doping of P elements lowered down the H adsorption energies involved in the water splitting process on the various active sites of P-NiCo2O4-10 catalyst, and thus enhanced its HER catalytic activities.

Seeking to design high-efficiency catalyst (LMO@N-rGO) for Li-O2 batteries, we suggested a one-step hydrothermal strategy to grow well-crystallized spinel LiMn2O4 (LMO) nanoparticles homogeneously on nitrogen-doped reduced graphene oxide nanosheets (N-rGO). We found that the prepared material can yield a twin-function battery, functioning as a Li-O2 (air) battery under the oxygen atmosphere and a Li-ion battery in the absence of oxygen. In the Li-O2 configuration, the material displayed a lower charge plateau voltage for 0.21 V and excellent cycling performance (120 cycles at 1000 mA h g–1 limited capacity). Furthermore, in the absence of oxygen, the material exhibited very good Li-ion battery cathode performance, achieving a capacity of up 80 mA h g–1. On the basis of our characterization results, three reasons are suggested for the twin performance of the material: the highly uniform dispersion of LMO nanoparticles, the improved Li diffusion kinetics, and the synergic effect between the spinel LMO nanop...

In this work, in-situ IR monitoring technique was employed to monitor the crystallization process of Zr-fumarate (Zr-fum) MOF in both H2O– and DMF-based systems. Wherein, the acid modulator (HCOOH) was only observed to be consumed in the DMF-based synthesis. Further solid-state NMR ex-situ results suggested the participations of HCOOH in the Zr-fum MOF structure formation, resulting in the possibility of formation of structural defects. This observation will further help to understand the formation of MOF structural defects from different solvent systems.

The wettability, or hydrophobic-hydrophilic balance, of cathode catalyst layer influences the performance of the proton exchange membrane fuel cell. In this paper, cathode catalyst layer with different polytetrafluoroethylene contents are prepared, and the effect of hydrophobic-hydrophilic balance on the performance of the membrane electrode assembly is investigated intensively. It is found that wettability, or hydrophobic-hydrophilic balance, of cathode catalyst layer can significantly affect the performance of membrane electrode assembly, and it can be effectively tuned by varying the loading of polytetrafluoroethylene. With the addition of polytetrafluoroethylene, the hydrophobicity of cathode catalyst layer, reflected by the contact angel, can be changed from 135.6° of that without addition of polytetrafluoroethylene to 146.5° with 70 wt.% polytetrafluoroethylene addition, and the optimal addition amount is 50 wt.%. For our optimal membrane electrode assembly with optimal addition of polytetrafluoroethylene in cathode, its current density are recorded as 990 mA cm–2 at 0.7 V and 1400 mA cm–2 at 0.6 V, respectively; its maximum power density is up to 856 mW cm−2. Furthermore, our polytetrafluoroethylene-incorporated membrane electrode assembly also exhibits excellent stability, and current density only drops from 1000 mA cm−2 to 900 mA cm−2 after a continuous operation of 60 h.

A high-performance Ni/Mo co-doped lithium manganate composite material, LiNi0.03Mo0.01Mn1.96O4, is prepared by a solid-state method, then a biomass-derived carbon layer with ethyl cellulose as the carbon source is applied to the surface of the composite particles. We find that carbon layer with the proper loading can significantly enhance the material’s cyclic stability and capacity at high discharge rates. At rates of 5C and 10C, our optimal sample (LNMMO-3wt%C), with 3 wt% carbon layer loading, has discharge capacities up to 114 and 98 mAh g−1, respectively, which are 10 and 8% higher than those of the uncoated co-doped material. Further, the carbon layer coating significantly improves the material’s stability at high discharge rates: the capacity retention of LNMMO-3wt%C after 400 cycles at discharge rates of 5C and 10C is high reaching 93.6 and 88.1%, respectively, compared with 91.4 and 74.3% for uncoated LNMMO. Based on our experimental results and analysis, we attribute the enhanced stability and capacity at high discharge rates to two factors: (i) enhanced conductivity and (ii) reduced Mn3+ dissolution, combined with significantly decreased resistance from Li+ ion intercalation/de-intercalation, due to the uniformity of the carbon layer coating.

In this study, two waste materials namely; coal fly ash (CFA) and waste tyres pyrolysis oil, were successfuly utilized in the synthesis of carbon nanofibers/tubes (CNF/Ts). In addition, Fe-rich CFA magnetic fraction (Mag-CFA) and ethylene gas were also used for comparison purposes. The carbons obtained from CFA were found to be anchored on the surface of the cenosphere and consisted of both CNTs and CNFs, whereas those obtained from Mag-CFA consisted of only multi-walled carbon nanotubes (MWCNTs). The study further showed that the type of carbon precursor and support material played an important role in determining the nanocarbon growth mechanism. The findings from this research have demonstrated that it is possible to utilize waste tyres pyrolysis oil vapor as a substitute for some expensive commercial carbonaceous gases.

In this study, we investigated the potential for use of waste tyre pyrolysis oil vapour as a carbon precursor in the synthesis of zeolite templated carbons (ZTC). With Zeolite 13X as the template, the ZTCs were synthesised using two methods namely: 1-step process which involved the carbonization of gaseous carbon precursor in the zeolite template (in this case, ethylene and pyrolysis oil vapour) and the 2-step synthesis method involved the impregnation of zeolite pores with furfural alcohol prior to carbonization of the gaseous carbon precursor. The replication of the zeolite 13X structural ordering was successful using both methods. The 2-step synthesized ZTCs were found to possess the highest specific surface area (3341 m2 g-1) and also had the highest H2 storage capacity (2.5 wt.%). The study therefore confirmed an additional novel strategy for value-addition of waste tyre pyrolysis by-products.

Aim: Our study investigated the significance of the crosstalk between long noncoding RNAs (lncRNAs) and mRNAs in gastric cancer (GC). Methods: lncRNA and mRNA expression profiling data in 671 GC tumors and 77 nontumorous gastric tissues were retrieved from the gene expression omnibus database: GSE54129, GSE13911, GSE19826, GSE79973, GSE15459 and GSE66229. Differentially expressed analysis, RNA coexpression network construction, gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses were conducted in this study. Results: Using differentially expressed and prognostic lncRNAs or mRNAs in GC, we constructed the lncRNA–mRNA coexpression networks. This network involved with vital GO and KEGG pathways. Conclusion: Our study reveals coexpressed lncRNAs and mRNAs as transcriptional hallmarks in GC patients which provide interesting information regarding the incidence and outcome of GC.

Slope failure in loess terrains of Northern China during spring thawing period is closely related to the freeze-thaw cycling that surface soils inevitably experienced. Field surveys were carried out on natural and artificial slopes in thirteen surveying sites located in the Northern Shaanxi, the center of Loess Plateau, covering five characteristic topographic features including tablelands, ridges, hills, gullies and valleys. Based on the scale that is involved in freeze-thaw cycling, the induced failures can be classified into three main modes, i.e., erosion, peeling and thaw collapse, depending on both high porosity and loose cementation of loess that is easily affected. Model tests on loess slopes with gradients of 53.1°, 45.0° and 33.7° were carried out to reveal the heat transfer, water migration and deformation during slope failure. The surface morphology of slopes was photographed, with flake shaped erosion and cracks noted. For three slope models, time histories for the thermal regime exhibit three obvious cycles of freeze and thaw and the maximum frost depth develops downwards as freeze-thaw cycling proceeds. Soil water in the unfrozen domain beneath was migrated towards the slope surface, as can be noticed from the considerable change in the unfrozen water content, almost synchronous with the variation of temperature. The displacement in both vertical and horizontal directions varies over time and three obvious cycles can be traced. The residual displacement for each cycle tends to grow and the slopes with higher gradients are more sensitive to potentially sliding during freeze-thaw cycling.

Freeze-thaw induced variations of the shear strength of loess is critical for evaluating the stability of natural and artificial slopes in loess terrains. The frequently encountered loess in Northern China was taken as the study object and two types of specimens were produced for direct shear testing including the undisturbed and the remolded. Strength behaviors of loess that has suffered preset cycles of freeze and thaw were investigated based on the particular correlations with freeze-thaw cycles, water content and dry density. Cohesion of the loess varied with the cycles of freeze and thaw until a residual value was reached while little change can be noted from the angle of internal friction. The apparent surface that was the first to be affected by freeze-thaw was compared with a quantified index of surface cracks determined by image processing. The meso-structural characters for loess after freeze-thaw cycling were explored such as the equivalent diameter, the particle orientation, the degree of circularity and the ratio of porosity area, with a damage variable that depends on the ratio of porosity area proposed. The coefficient of safety for a natural loess slope was calculated by considering the coupled effect of freeze-thaw cycles, frozen depth and the initial water content. This may provide guidance in predicting the stability of slopes in loess terrains when the freeze-thaw is included.

Tin oxide (SnO2) is widely used in perovskite solar cells (PSCs) as an electron transport layer (ETL) material. Ethanol usually serves as a solvent of ETL but no one discussed the possible influences caused by ethanol. In this work, the effects of ethanol were investigated systematically. It is clear that ethanol treatment (EtOH-SnO2) can remove surface disorder of mesoporous SnO2 and thus enhance the conductivity as well. As a result, the champion PCE of 21.62% is obtained in PSC with EtOH-SnO2 ETL, which is higher than that of control device (20.70%) due to improved film quality. Meanwhile, compared with control PSCs, the stability of the perovskite layer deposited on EtOH-SnO2 ETL is gradually improved both for the light and thermal stability. Therefore, we make clear that the ethanol treatment can improve the quality of mesoporous SnO2 and perovskite films for optoelectronic device.

This study examined the corrosion inhibiting properties of parsley (petroselinum sativum) essential oils, for Type 430 ferritic stainless steel in 0.5 molar sulphuric acid solutions. In this study, weight loss, electrochemical and scanning electron microscope techniques were used in gaining a detailed understanding of inhibition effects of parsley (petroselinum sativum) essential oils (PEO) on Type 430 ferritic stainless steel corrosion. The inhibitor studied exhibits good anti-corrosion performance with 98.65% inhibition efficiency. This result could be ascribed to the adsorbed PEO on the surface of the stainless steel, and this was verified by surface visualization using optical and scanning electron microscope techniques while the crystallographic variation of the inhibited sample is studied by x-ray diffraction (XRD). The adsorption of PEO onto stainless steel surface is controlled by Langmuir adsorption isotherms. Optical images of non-inhibited specimens showed a severely corroded surface with a visible macro pit on the stainless steel from sulphuric solutions. The inhibited sample shows improved surface owing to the surface protection effect of PEO molecules. The corrosion inhibition performance of PEO is due to the presence of active constituents which enhanced the film formation over the surface of the metal, thus, mitigating corrosion.

The performance evaluation on water splitting electrodes is usually conducted in laboratory at current density range of 10–100 mA cm−2, and this is far from satisfactory for the industrial practices that require the operating current density larger than 400 mA cm−2. In this work, an efficient hybrid electrode is developed by firstly electro-etching the nickel mesh (E-NM) in actual seawater and then in-situ depositing nickel nanowires (NWs) onto E-NM substrate under the externally applied magnetic field. The results show that NWs are integrated into the defective E-NM structure. The assembled NWs/E-NM hybrid electrode achieves a high current density of 800 mA cm−2 at 2.0–2.1 V, which outperforms the commercial NM electrode. Moreover, the current density does not decay after 100 h stability test at 500 mA cm−2.

The fabrication of application-specific metal-organic framework (MOF) composites has the potential to shift more towards hydrogen storage system integration. The in-situ growth of nano particles on a graphene surface is a common technique for synthesizing graphene-inorganic nanocomposites and in this study, a graphene foam (GF) / zirconium-based MOF (UiO-66) composite was prepared using a two-step solvothermal method. Brunauer, Emmett and Teller (BET) surface area as well as hydrogen uptake capacity were measured under cryogenic conditions and compared to the values for pristine UiO-66. The GF/UiO-66 composite had a BET surface area of 1073 m2.g-1 and a hydrogen uptake capacity of 1.1 wt% at 77 K and 1.2 bar pressure, compared to 1367 m2.g-1 and 1.5 wt%, respectively for pristine UiO-66 under the same conditions. Besides the values being compromised relative to pristine UiO-66, the two-step in-situ synthesis approach yielded a composite with enhanced BET surface area and H2 uptake relative to a composite obtained from a single step synthesis approach. The composites further exhibited better thermal stability than the pristine UiO-66 and show promise for the development of powdered MOF materials towards hydrogen storage system integration.

We report a rare case whereby a metal–organic framework (MOF), namely UiO-66, is compacted at high pressure (∼700 MPa or 100 000 psi) resulting in densification and improved total volumetric hydrogen storage capacity, but crucially, without compromising the total gravimetric uptake attained in the powdered form of the MOF. The applied compaction pressure is also unprecedented for MOFs as most studies have shown the MOF structure to collapse when compacted at very high pressure. The UiO-66 prepared in this study retained ∼98% of the original surface area and microporosity after compaction at ∼700 MPa, and the densified pellets achieved a total H2 uptake of 5.1 wt% at 100 bar and 77 K compared to 5.0 wt% for the UiO-66 powder. Depending on the method used to compute the volumetric uptake, the densified UiO-66 attained unprecedented volumetric capacity at 77 K and 100 bar of up to 74 g L−1 (13 g L−1 at 298 K) compared to 29 g L−1 for the powder (6 g L−1 at 298 K) using a conventional method that takes into account the packing density of the adsorbents, or 43 g L−1 (compared to 35 g L−1 for the powder at 77 K and 100 bar) based on a method that uses both the single crystal and skeletal densities of MOFs. However, regardless of the difference in the calculated values according to the two methods, the concept of UiO-66 compaction for improving volumetric capacity without compromising gravimetric uptake is clearly proven in this study and shows promise for the achievement of hydrogen storage targets for a single material as set by the United States Department of Energy (DOE).

The cycling stability of Li–O2 batteries has been impeded by the lack of high-efficiency, and durable oxygen cathodes for the oxygen-reduction reaction (ORR) and the oxygen-evolution reaction (OER). Herein we report a novel TiN nanorod array-based cathode, which was firstly prepared by growing a TiN nanorod array on carbon paper (CP), and then followed by depositing MnO2 ultrathin sheets or Ir nanoparticles on the TiN nanorods to form well-ordered, three-dimensional (3D), and free-standing structured cathodes: TiN@MnO2/CP and TiN@Ir/CP. Both cathodes exhibited good specific capacity and excellent cycling stability. Their specific discharge capacities were up to 2637 and 2530 mA h g−1, respectively. After 200 cycles for 2000 h at a current density of 100 mA g−1, no obvious decays were observed for TiN@MnO2/CP and TiN@Ir/CP cathodes, while significant decreases were observed after the 80th and 30th cycles for the Pt/C and TiN/CP cathodes, respectively. Such high performance can be ascribed to the 3D array structure with enough microspace and high surface area, which facilitated the high dispersion of active components and prevented the formation of large/irreversible Li2O2.

The increase in waste tyres has led scientist in the quest for finding various ways for minimizing problems associated with their disposal. The sought solutions are not only meant to be environmentally friendly but also be able to boost the economy. Pyrolysis of waste tyres is one of the preferred ways of recycling waste tyres since it gives valuable products such as pyrolysis oil, gas and solid char. Solid char has low surface area and contains inorganic traces that disadvantage it from competing with commercial carbon black. The aim of this study was to apply the mechanochemical approach, which is the compaction of the solid char with an activating agent before the activation process in order to increase reactive sites. The solid char was initially treated with water, HF and HNO 3 prior to the mechanochemical approach. The obtained materials were analysed using EDS, XRD and FTIR. The textural properties were also studied using N 2 sorption isotherms. The HNO 3 washed and compactivated CB had the highest surface area of 955.20 m 2 /g and also the highest H 2 storage capacity of 1.4 wt.% at 1 bar.

The comparable catalytic activities of non-noble metal electrocatalysts are the prime to enable their breakthrough performances for oxygen reduction reaction (ORR). In this work, the nitrogen-doped carbon aerogels are strategically functionalized with Ce/Fe elements. The increased content of pyridinic nitrogen from 16.71% to 20.28% coupled with a macro-porous structure result in an enhanced ORR catalytic performance. The performance evaluation shows that the ORR onset potential of the functionalized sample shifts from 0.893 V to 0.968 V comparing to the unfunctionalized sample. The open cell voltage reaches 1.450 V when the optimal catalyst is assembled into a zinc-air cell as the cathode, and such performance is comparable to the commercial Pt/C catalyst.

Metal-organic frameworks (MOFs) are promising adsorbents for adsorptive desulfurization (ADS) because MOF structure can be tuned to match the application. However, data on the ADS of liquid fuels using Ni-BDC are still scarce. In this study, modulated synthesis was used to prepare a group of Ni-doped MOF absorbents using formic acid as the modulator. The activities of these adsorbents for the ADS of model fuels were investigated, with initial sulfur concentrations of 150, 151, and 153 ppm for thiophene (TH), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6 DMDBT), respectively. Although Ni-doping decreased the crystallinity and crystallite size of the MOFs, the addition of formic acid significantly increased both the crystallite size and crystallinity of all the (xNi/Zn)-BDC materials. In addition, it was observed that modulated synthesis reduced the interpenetration of the MOF-5 crystallites. The adsorption experimental results showed that the modulated synthesis of Ni-BDC using formic acid improved the overall adsorptive activity of Ni-BDC almost twofold. This increase in activity was attributed to increased crystallinity and a higher number of atoms with low coordination for modulated Ni-BDC compared with MOF-5 (100). Formic acid as a modulator was observed to have three effects: i) accelerating MOF synthesis, ii) modulating crystallite size, and iii) controlling crystallinity. The most active adsorbent, Ni-BDC treated with formic acid, was observed to have higher activity toward TH than DBT and 4,6 DMDBT. The overall adsorption capacity and partition coefficient for this adsorbent were 4.14 mg/g and 0.053 mg/g/ppm, respectively.

Loop heat pipe has a wide application in the fields of airborne electronics cooling and thermal management. However, the pertinent temperature oscillation of the loop heat pipe could lead to adverse effects on the electronics. In the current study, an ammonia-stainless steel dual compensation chamber loop heat pipe was developed to experimentally investigate the temperature oscillation under different acceleration conditions. The impact of several control parameters such as different heat loads, loading modes, acceleration directions and magnitudes on the operational performance of the loop heat pipe was analyzed in a systematic manner. The heat load applied on the evaporator ranged from 25 W to 300 W. The acceleration magnitude varied from 1 g to 9 g and four different acceleration direction, i.e. configurations A, B, C and D, were taken into account. Two different loading modes were applied with different heat load and acceleration force. Experimental results show that (i) the loop temperature will change and oscillate as the acceleration force was applied under all test conditions. It can be easily found that the temperature oscillation occurred at both heat loads of 250 W and 300 W. (ii) for the case of the first loading mode, periodic temperature oscillation is observed on the liquid line, whereas for the second loading mode, periodic temperature oscillation can be easily appeared on the entire loop. (iii) the loop temperature under both configurations A and B with acceleration of 7 g does not oscillate at heat load of 150 W, 200 W and 250 W when the first loading mode is applied. Especially under configuration B, the acceleration could contribute to repress the temperature oscillation. Under the current heat loads for almost all cases, the temperature oscillation can be observed for configurations A, C and D with acceleration of 5 g. (iv) the amplitude of evaporator at heat load of 300 W under configuration C are 0.6 °C, 0.3 °C, 0.2 °C and 0.3 °C with acceleration of 3 g, 5 g, 7 g and 9 g. The corresponding period is 66 s, 36 s, 34 s and 36 s, respectively.

This clinical trial developed a personalized dosing model for reducing prostaglandin E2 (PGE2) in colonic mucosa using ω-3 fatty acid supplementation. The model utilized serum eicosapentaenoic acid (EPA, ω-3):arachidonic acid (AA, ω-6) ratios as biomarkers of colonic mucosal PGE2 concentration. Normal human volunteers were given low and high ω-3 fatty acid test doses for 2 weeks. This established a slope and intercept of the line for dose versus serum EPA:AA ratio in each individual. The slope and intercept was utilized to calculate a personalized target dose that was given for 12 weeks. This target dose was calculated on the basis of a model, initially derived from lean rodents, showing a log-linear relationship between serum EPA:AA ratios and colonic mucosal PGE2 reduction. Bayesian methods allowed addition of human data to the rodent model as the trial progressed. The dosing model aimed to achieve a serum EPA:AA ratio that is associated with a 50% reduction in colonic PGE2. Mean colonic mucosal PGE2 concentrations were 6.55 ng/mg protein (SD, 5.78) before any supplementation and 3.59 ng/mg protein (SD, 3.29) after 12 weeks of target dosing. In secondary analyses, the decreases in PGE2 were significantly attenuated in overweight and obese participants. This occurred despite a higher target dose for the obese versus normal weight participants, as generated by the pharmacodynamic predictive model. Large decreases also were observed in 12-hydroxyicosatetraenoic acids, and PGE3 increased substantially. Future biomarker-driven dosing models for cancer prevention therefore should consider energy balance as well as overall eicosanoid homeostasis in normal tissue. Cancer Prev Res; 10(12); 729–37. ©2017 AACR.

High-performance ferric phosphate (FePO4), with well-defined ellipsoid morphology and uniform particle size distribution, is successfully fabricated via a green spray drying method with formic acid as additive. It is found that the added formic acid plays a crucial role for the formation of the well-distributed FePO4 particles. Benefited by the outstanding structure and properties of ferric phosphate prepared above, a high performance of lithium iron phosphate (LiFePO4) has been prepared. It exhibits high capacity, especially at high charging/discharging rate (158.4 mAh g−1 at 0.2 C and 107.3 mAh g−1 at 10 C), and excellent cycling stability (without capacity fading after cycling for 200cycles at 1 C). All these impressive electrochemical performance could be ascribed to the FePO4 precursor, and further attributed to the addition of formic acid, which may play as a template, resulting in the well-defined morphology, uniform particles size distribution, hierarchical pore structure, and high surface area of the ferric phosphate.

Metal-organic frameworks (MOFs) have been under development over the past 20 years. Similar to other technologies, research on MOFs in the upcoming 30 years will move towards the direction where MOF materials can deliver societal benefits by solving real-world problems. Taking technology from laboratory to applications is always a challenge. Analysis of the current MOFs research efforts indicates that the high cost, limited availability of MOF products and the knowledge gap for cost-effective production technologies account for the slow progression towards the development of envisioned MOF products at pilot-scale level. This short review brings together the scattered literature that addresses pilot-scale production of MOF materials. An additional aspect focuses on the progress on the development of pilot-scale synthetic strategies with green and sustainable features for MOF materials, which is an imperative to promote MOF-enabled products into the real world.

Background Dehydroepiandrosterone sulfate (DHEAS) is the most abundant steroid in human circulation, and adrenocorticotropic hormone (ACTH) is considered the major regulator of its synthesis. Pregnenolone sulfate (PregS) and 5-androstenediol-3-sulfate (AdiolS) have recently emerged as biomarkers of adrenal disorders. Objective To define the relative human adrenal production of Δ5-steroid sulfates under basal and cosyntropin-stimulated conditions. Methods Liquid chromatography-tandem mass spectrometry was used to quantify three unconjugated and four sulfated Δ5-steroids in (1) paired adrenal vein (AV) and mixed venous serum samples (21 patients) and (2) cultured human adrenal cells both before and after cosyntropin stimulation, (3) microdissected zona fasciculata (ZF) and zona reticularis (ZR) from five human adrenal glands, and (4) a reconstituted in vitro human 17α-hydroxylase/17,20-lyase/(P450 17A1) system. Results Of the steroid sulfates, PregS had the greatest increase after cosyntropin stimulation in the AV (32-fold), whereas DHEAS responded modestly (1.8-fold). PregS attained concentrations comparable to those of DHEAS in the AV after cosyntropin stimulation (AV DHEAS/PregS, 24 and 1.3 before and after cosyntropin, respectively). In cultured adrenal cells, PregS demonstrated the sharpest response to cosyntropin, whereas DHEAS responded only modestly (21-fold vs 1.8-fold higher compared with unstimulated cells at 3 hours, respectively). Steroid analyses in isolated ZF and ZR showed similar amounts of PregS and 17α-hydroxypregnenolone in both zones, whereas DHEAS and AdiolS were higher in ZR (P < 0.05). Conclusion Our studies demonstrated that unlike DHEAS, PregS displayed a prominent acute response to cosyntropin. PregS could be used to interrogate the acute adrenal response to ACTH stimulation and as a biomarker in various adrenal disorders.

The performance of the proton exchange membrane fuel cell (PEMFC) is significantly improved through introducing nitrogen-doped carbon nanotubes (NCNTs) into the catalyst layer (CL) and microporous layer (MPL) of the membrane electrode assembly (MEA), it reveals by SEM images that the NCNTs are uniformly dispersed in CL and MPL, resulting in the more plenty of porosity, higher surface area, better conductivity, and better prevention of the layer cracks. The BET surface area and pore volume of MPL are increased by 88% and 77% respectively with the addition of 20 wt% of NCNTs in MPL. The membrane electrode assembly (MEA) with adding 20 wt% NCNTs both in cathode CL and in cathode GDL can yield the best cell performance. At a cell temperature of 70 °C and 30 psi back pressures, the current density is up to 1000 mA cm−2 at 0.7 V and 1600 mA cm−2 at 0.6 V, and the max power density reaches 997 mW cm−2.

A composite material consisting of Zr-based metal organic framework (Zr-MOF) and reduced graphene oxide (rGO) was successfully synthesized by an in situ method. The aim of the study was to transfer some of the graphene's attractive properties to the MOF materials. An important observation was that the incorporation of rGO did not alter or interfere with the crystallization of the MOF material. The studies showed an increase in surface area for the rGO/Zr-MOF composite (1480 m2/g) when compared to that of pristine Zr-MOF (1116 m2/g). There was also an enhancement of the hydrogen storage capacity from 1.4 wt% to 1.8 wt% for the GO/Zr-MOF composite. This enhancement could be attributed to the synergistic contribution of interactions of rGO sheets with hydrogen as well as from the possible expansion of the pore space in the Zr-MOF induced by the presence of the graphene-like material.