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In this paper, the mechanical properties of polyvinyl chloride (PVC)-coated woven fabric at high-temperature and after exposure to high-temperature were studied using a uniaxial tensile test. The test temperature range is 20 °C to 170 °C. The high-temperature test shows that the maximum stress at 170 °C reduced to 57%−59% of that at 20 °C. The after exposure to high-temperature test of prestressing shows that the combined effect of high-temperature and constant external force enhanced the stiffness and reduced the material’s impact toughness. The experimental phenomena can be explained by polymer physics.

Catalysts of Ni supported on home-made mesoporous alumina (Ni/M-Al2O3) were prepared via facile incipient impregnation method and calcined under different temperature (500–800 °C). Compared with catalysts of Ni supported on commercial alumina, they showed much higher conversion and lower carbon deposition in methane dry reforming (DRM). Among the catalysts, Ni/M-Al2O3-700 exhibited the highest DRM activity, with 77.6% CH4 conversion and 85.4% CO2 conversion at 700 °C. TPR revealed that almost all the Ni was in the form of NiAl2O4 spinel after calcination at 700 °C. Due to the strong metal-support interaction of NiAl2O4 structure, the Ni crystal size of Ni/M-Al2O3-700 after reduction was around 5 nm. TGA and TEM results showed its carbon deposition after 20 h DRM test was only 3.8% and mainly in the form of amorphous carbon. This work indicates that the formation of NiAl2O4 spinel is beneficial to activity and stability towards DRM reaction and controlling calcination temperature is crucial.

Catalysts/co-catalysts for cathodic oxygen reduction and anodic methanol oxidation reactions (ORR/MOR) play the major roles in promoting the commercialization of direct methanol fuel cells. Herein, bimetallic zeolite-imidazolate-frameworks (CoZn-ZIFs) is used as precursor to synthesize Co3O4@NPC/CuO composites as catalysts for ORR and Pt supports/co-catalysts for MOR. The ORR activity (E1/2 = 0.83 V) and long-term stability (activity retention of 85.5% after 30,000 s) of Co3O4@NPC/CuO-400 (400 °C) dodecahedron are better than those of commercial Pt/C (10 wt%) in alkaline electrolytes. The surface CuO with variable valence states (Cu0 and Cu2+) can be used as both the active component for ORR and the protective layer for Co3O4 to enhance catalytic stability. Partial removal of CoOx from carbon framework promotes the exposure of highly active sites (Co2+) on the Co3O4. For MOR, the mass activity of Pt-Co3O4@NPC/CuO-400 (5 wt%) (1947 mA mgPt−1) is much higher than that of Pt/C (751 mA mgPt−1), mainly attributing to that the Pt active sites are uniformly dispersed on Co3O4@NPC/CuO support. The strong interaction between Pt and CuO can reduce the bond strength of Pt-CO to enhance CO resistance. Co3O4 can activate H2O molecules to provide sufficient OH− species to promote MOR. This study provides a new idea for preparation of active ORR catalysts and MOR co-catalyst from bimetallic ZIFs.

Germanium selenide attracts emerging attention for applications in high-performance field-effect transistors and photodetector, due to its unique photoelectric performances and tunable bandgap. Herein, the germanium selenide-reduced graphene oxide (GeSe-RGO) hybrid is successfully synthesized by loading liquid-phase exfoliated GeSe nanosheets on the 2D graphene via a hydrothermal reduction process. It is demonstrated that the photoresponse performance of the photoelectrochemical (PEC) device constructed by the synthesized GeSe-RGO hybrid is significantly enhanced in comparison to the one built by the sole GeSe nanosheets. The results of the PEC tests display the photocurrent density can reach to 8.45 μA/cm2 at the bias of 0.8 V, which is approximately 4 times that of sole GeSe nanosheets. Meanwhile, with the increase of illumination intensity, the photocurrent density of the GeSe-RGO photodetector almost presents a linear increase. When the illumination intensity is 90 mW/cm2, the photoresponsivity value is up to 116 μA/W. In addition, the GeSe-RGO hybrid shows a durable photoresponse capability under the bias of 0 V, revealing that such a hybrid has the excellent self-powered ability in the PEC system. There is no evident degradation on the photoresponsive performance of GeSe-RGO photodetector after 50 light on-off cycling, indicating the good stability of the hybrids. The enhanced performance of the GeSe-RGO hybrid is attributed to the outstanding photoresponsive capability of RGO and the effective separation of photo-generated electron-hole pairs. Our work indicates that the GeSe-RGO hybrid has great prospects for future applications in PEC-type photodetector devices.

Anion redox chemistry plays a crucial role in Na-deficient or Na-rich oxide cathodes for sodium-ion batteries (SIBs). But the oxygen redox chemistry has been rarely reported in O3-type (Na-full) layered oxides for SIBs. Herein, we reveal the anion redox chemistry in O3-type NaMn1/3Fe1/3Ni1/3O2 (MFN) cathode material, and propose an integrated strategy combining ZrO2 coating and Zr4+ doping to tune the anionic redox chemistry and crystal structures which improves the activity, reversibility, and stability of O2−. Oxygen redox reactions with high reversibility and cyclic stability mainly occur between 4.0 V and 4.3 V. The structure of Na-O-TM is regulated by Zr4+ doping, and the electronic state of O-2p occupies a higher energy level by the regulation of Na-O-TM structure. The electrons can migrate from O2- more easily and O2−/O− contribute more capacity. Zr4+ doping optimizes the lattice structure, enlarges the Na layer, and decreases TMO2 layer, which reduces the diffusion resistance of Na+ and increases the structural stability. ZrO2 layer effectively mitigates the corrosion of the electrolyte and ensures the integrity of the structure, which inhibits the formation of Na2CO3 on the surface and decreases CO2 release. This study not only reveals the anion redox chemistry in O3-type layered oxide cathode material but also is available for insights into regulating the redox activity, reversibility, and stability of oxygen.

Bone mineral consists of calcium hydroxy-carbonate apatite (HCA) that incorporates other minor cation substituents, primarily Na+ (0.5–0.8 wt %). We examine the carbonate species in various HCA spe...

Oxygen release and irreversible cation migration are the main causes of voltage fade in Li-rich transition metal oxide cathode. But their correlation is not very clear and voltage decay is still a bottleneck. Herein, we modulate the oxygen anionic redox chemistry by constructing Li2ZrO3 slabs into Li2MnO3 domain in Li1.21Ni0.28Mn0.51O2, which induces the lattice strain, tunes the chemical environment for redox-active oxygen and enlarges the gap between metallic and anionic bands. This modulation expands the region in which lattice oxygen contributes capacity by oxidation to oxygen holes and relieves the charge transfer from anionic band to antibonding metal–oxygen band under a deep delithiation. This restrains cation reduction, metal–oxygen bond fracture, and the formation of localized O2 molecule, which fundamentally inhibits lattice oxygen escape and cation migration. The modulated cathode demonstrates a low voltage decay rate (0.45 millivolt per cycle) and a long cyclic stability., Voltage fade is a critical issue for Li-rich transition metal oxide cathode. Here, the authors modulate the oxygen anionic redox chemistry and enlarges the gap between metallic and anionic states by constructing Li2ZrO3 slabs into Li2MnO3 domain in Li1.21Ni0.28Mn0.51O2 which fundamentally suppresses the voltage decay.

P2-type Na0.67Mn0.75Fe0.25O2 cathode materials with low cost and high specific capacity have aroused much interest for sodium-ion batteries. Nevertheless, the cyclic and structural stabilities need...

The argon power cycle is one of the most promising technologies for high efficiency and low emission hydrogen-fueled internal combustion engines. The application of coaxial injection technology in the hydrogen-fueled argon engine can improve the mixing process and the combustion performance of the H2/O2 mixture. In this study, an innovative H2–O2 coaxial injection combustion system was designed to investigate the jet flame characteristics of oxygen coaxially wrapped by hydrogen in a controllable argon thermal atmosphere. The findings of this study could provide a new perspective for designing hydrogen-fueled argon engines in the future. The influences of co-flow temperature, jet injection pressure, and excess oxygen coefficient were all determined. Observations of the flame showed a bright blue flame with a reddish glow in the far-burner region. Experimental results show that the flame length, cross-sectional area, and area/perimeter ratio first decrease with increasing jet injection pressure and subsequently increase, reaching maximum values at 0.4–0.6 MPa. When increasing the co-flow temperature from 1023 K to 1223 K, the cross-sectional area of the flame increases significantly by 61.1% at an excess oxygen coefficient of 0.4. Furthermore, the liftoff flame height shrinks when the co-flow temperature and the excess oxygen coefficient increase, while it rises along with an increasing jet injection pressure.

Graphite anode materials are widely used in commercial lithium-ion batteries; however, the long electron/ion transportation path restricted its high energy storage. In this experiment, we designed a copper/graphite composite with a dual three-dimensional (3D) continuous porous structure combining used nonsolvent-induced phase separation and heat treatment, in which a large amount of graphite is embedded in the 3D porous copper/carbon architecture. In the novel structure, not only the electron and Li+ transmission performances are improved, but also the space of current collector is fully utilized. Meanwhile, carbonized polyacrylonitrile network stabilizes the interface between graphite and copper matrix. The obtained copper/graphite composite anode has an initial discharge capacity of 524.6 mAh·g−1, a holding capacity of 350 mAh·g−1 and excellent cycle stability (299.3 mAh·g−1 after 180 cycles at 0.1C rate), exhibiting good electrochemical performance. The experimental results show that the mass loading of the copper/graphite composite electrode material is about 4.39 mg·cm−2. We also envisage replacing graphite with other high-capacity active materials to fill the current collector, which can provide a reference for the future development of next-generation advanced electrodes.

Metalorganic hydrides are a new class of hydrogen storage materials. Replacing the H of N–H or O–H functional groups using metal hydrides have been recently reported, which substantially improved the dehydrogenation properties of heteroaromatic organic hydrides by lowering their enthalpies of dehydrogenation (ΔHd), enabling dehydrogenation at much lower temperatures. Among the reported metalorganic hydrides, lithium carbazolide and sodium carbazolide appear to be the most attractive hydrogen storage/delivery material owing to its high hydrogen capacity (>6.0 wt%) and ideal ΔHd. Nevertheless, the interaction of carbazole and corresponding metal hydride to form metallo-carbazolide is a multistep process involving intensive ball milling and high temperature treatment, where the interaction was not investigated in detail. In this paper, both alkali metal hydrides and amides were employed to react with carbazole to synthesize corresponding carbazolides, aiming to broaden and optimize the synthetic method and understand the reaction mechanism. Our experimental results showed that around one equivalent of H2 or NH3 could be released from the reactions of carbazole and corresponding hydrides or amides, respectively. Instrumental spectroscopic analyses proved that metallo-carbazolides were successfully synthesized from all precursors. It is found that the alkali metal amides (i.e., LiNH2 and NaNH2) with stronger Lewis basicities as metal precursors could synthesize the metallo-carbazolides under milder conditions. Furthermore, quasi in situ nuclear magnetic resonance results revealed that alkali metal could replace H (H–N) gradually, donating more electrons to carbazole ring. Additionally, the solubilized alkali cation may unselectively interact with π-electron of aromatic systems of both carbazole molecules and carbazolide anions via electrostatic cation-π interactions.

Lithium-metal batteries (LMBs) are promising electrochemical energy storage devices with high energy densities. However, the extreme reactivity of metallic lithium, the large volumetric change of the electrode during cycling, and the notorious dendrite formation issues lead to low cyclic stability and safety concerns, hindering the practical application of LMBs. In particular, the intrinsic tendency of uneven lithium deposition and the large internal electrode stress lead to the piecing of solid electrolyte interphases (SEIs), thereby resulting in fast decay of the anode. We develop a facile laser processing technique to fabricate laser-structured copper foils (LSCFs) that are able to regulate the lithium deposition kinetics and increase the cycle life of LMBs. By simply scribing commercial foils using a 355 nm laser, microstructural features with fish-scale patterns are obtained. The lithium deposition follows a drastically different mode on the LSCF compared with commercial planar copper foils which relieves the internal stress of lithium and prohibits the piecing of SEI. A high Coulombic efficiency of >96% of the lithium metal anode is maintained for over 100 cycles on the LSCF at a current density of 1 mA cm-2 and an areal capacity of 1 mAh cm-2 while the benchmark decayed to below 80% after 50 cycles. Full cells based on LiFePO4 cathodes display a reasonable specific capacity of 125 mAh g-1 over 300 cycles at a rate of 1 C. This work provides a fast yet effective laser-based approach to construct highly stable lithium metal anodes.

Biomass-derived graphitic carbon is becoming an attractive material for anodes in lithium-ion and sodium-ion batteries (LIBs and SIBs) owing to its sustainability. The graphitization of biochar by heating above 2600 °C not only requires high energy consumption but also removes heteroatoms that are conducive to electrochemical energy storage. In this study, graphitic carbon nanosheets with N/P-dual doping are facilely synthesized by one-step carbonization of pine sawdust at 800/1000/1200 °C that is priorly dissolved in 1-butyl-3-methyl-imidazolium ([Bmim]H2PO4) and used as anodes of LIBs/SIBs, respectively. [Bmim]H2PO4 simultaneously promotes the graphitization and porosities of the biochar as carbonization temperature increases in addition to providing N/P-dual doping. Used as anodes of LIBs, IWC-1200 demonstrates excellent rate performance and cyclic stability, delivering 385 mAh g−1 at 1 Ag−1 throughout 1000 cycles. For sodium storage, IWC-1000 exhibits stable capacities of 217 mAh g−1 at 0.1 A g−1 and 101 mAh g−1 at 1 Ag−1. The electrochemical performances benefit from the graphitized structure with N/P-dual doping, leading to redox pseudocapacitance for lithium/sodium storage. DFT calculations suggest that pyridinic N strongly attracts both Li and Na while P atoms inside the graphitic structure significantly increase the interlayer spacing.

This article presents the first dedicated system-on-chip (SoC) that supports full data analysis workflow for genetic variant discovery for next-generation sequencing (NGS). The SoC implements four major steps: preprocessing, short-read mapping, haplotype calling, and variant calling. By adopting the sBWT-based short read mapping and Genome Analysis ToolKit haplotype caller-based variant calling algorithms, this work achieves a comparable precision as the software solutions. The dedicated hardware architecture achieves high parallelism with low hardware complexity. In this SoC, the multitask sorting engine and the dynamic programming processing engine are proposed for essential computing tasks for NGS data analysis. An ARC processor is integrated to facilitate IO interfaces, including a DDR3 PHY. Fabricated in a 28-nm technology, the chip area is 12 mm2. It dissipates 975 mW at a clock frequency of 400 MHz from a 0.9-V supply. The SoC is able to complete variant discovery for the whole human genome within 37 min. Compared with an optimized graphic processing unit solution, this work is 66 $\times $ faster and also achieves an $1.59\times 10^{4}$ times higher energy efficiency and 3086 $\times $ higher area efficiency. Verified with the FDA standardized benchmark, the SoC achieves a precision of 99.6%. The prototype system demonstrates the analysis procedure in real time for on-site DNA sequencing.

Understanding self-crystallization characteristics of calcium-magnesium-alumina- silicate (CMAS) glass is of great significance for seeking for solution to its corrosion to thermal barrier coatings (TBCs). Here, we design a series of experiments to investigate the relationship between CMAS self-crystallization behavior and cooling/heating rates and dwell temperature, and emphasize the potential influence of self-crystallization on CMAS corrosion behavior to TBCs. With the cooling rate decreasing, crystalline phases formed in a sequence of diopside, wollastonite and anorthite, and the thickness of the crystalline layer increased. During the heating process, diopside and melilite phases formed when the temperature was lower than 1050 °C; while at higher temperatures, melilite transformed to anorthite and wollastonite, independent on the heating rate. Although self-crystallization can slow molten CMAS penetration, the function on protecting TBCs from damage is limited, and other strategies alleviating CMAS corrosion are necessitated to be developed.

Lattice oxygen undergoes redox reaction to achieve high specific capacity of the material in lithium-rich cathode oxides. However, irreversible oxygen loss causes a change in the crystal structure, and the cations migrate in the transition metal layer, resulting in a rearrangement of the electronic structure and ultimately a severe voltage decay. Herein, we introduce Pt nanoparticles with good catalytic activity and electrical conductivity into lithium-rich cathode materials to improve the loss of lattice oxygen for the first time. We have revealed that the evolution of the lattice structure after the lattice oxygen redox reaction is relatively stable in the lithium-rich oxide with Pt nanoparticles, which is in stark contrast to the apparently deformed crystal structure in the lithium-rich oxide without Pt. Pt-containing electrodes exhibit excellent high-capacity retention rate (more than 80% after 200 cycles), and voltage decay is significantly reduced (less than 0.4 V after 200 cycles). Our results highlight the role of Pt nanoparticles in alleviating the loss of lattice oxygen and stabilizing the crystal structure, which opens up the field of vision for the design of high-energy-density lithium rich cathode oxides with stable structure.

In the manuscript, water-soluble polysaccharides WPNI was extracted from notopterygium incisum roots and separated into two homogeneous fractions WPNI-A-a and WPNI-A-b. WPNI-A-a was an arabinogalactan (AG). WPNI-A-b belonged to HG type pectin. The structure of WPNI-A-b was analyzed by FT-IR, NMR, enzymatic hydrolysis (Endo-PG) and UPLC-FLD-MSn. WPNI-A-b was dominated by HG domain, covalently linked with AG and RG-II domains. Oligogalacturonides produced by Endo-PG from HG domain were non-, mono-, di- or tri-methyl esterified with degree of polymerization (DP) from 1 to 6. The distribution of methyl-ester groups was in a block-wise manner. The interaction of WPNI-A-b and its enzymatic hydrolysis products with galectin-1, galectin-3, galectin-7 and galectin-8 showed that AG domain exhibited stronger binding avidity to galectins than RG-II and HG domain, while oligogalacturonides showed no binding activities to galectins. The results would be useful for the application of the pectin from notopterygium incisum.

Hyaluronic acid (HA) is recognized as a functional carbohydrate polymer applied for the surface modification of cardiovascular implanted materials due to its molecular weight (MW) dependent cellular regulation. However, due to the enzyme digestion of hyaluronidase on HA in vivo, the stability of HA MW needs to be further improved. It has been reported that the stability of HA MW can be improved by sulfonation. In this study, sulfonated hyaluronic acids (S-HA) with sulfur content of 2.06, 3.69, 7.10, 8.98, and 9.71 were prepared through different sulfuric acid treatment procedures. Cell tests showed that S-HA with higher sulfur content played a significant role in promoting the proliferation and migration of endothelial cells and regulating smooth muscle cells to the physiological phenotype. In addition, it was also proved to inhibit the inflammatory macrophages adhesion/activation. Our data indicates that S-HA may be a better carbohydrate polymer for potential application of cardiovascular biomaterials.

Copper phyllosilicate supported over silica was prepared with ammonia evaporation method. Compared with the catalyst synthesized with conventional impregnation method, this novel catalyst showed a much higher activity and stability towards low-temperature water-gas shift reaction. Various characterization methods indicated the Cu nanoparticle in the catalyst had a superb small diameter around 3 nm, co-existent with abundant Cu+ sites. Based on the analysis via CO-adsorption, DRIFTS and in-situ mass spectrum, it was proved that CO could be adsorbed on Cu+ strongly and Cu+ acted as the active sites for CO activation. The reaction mechanism with dual active sites prevented the competitive adsorption of H2O and CO onto Cu0 sites, thereby improving the catalytic activity and stability.

A symmetric 2D CFD model of catalytic membrane reactor for dry reforming of methane (DRM) was built up. Nondimensionalization method was employed and the governing equations were simplified. Crucia...

From a multitude of homonuclear and heteronuclear correlation magic-angle-spinning (MAS) NMR experiments, we present thorough structural and phase-quantification analyses of calcium phosphate cemen...

The effects of ultrasonic treatment on rheological and emulsifying properties of sugar beet pectin were studied. Results indicated that intrinsic viscosity ([η]) and viscosity average molecular weight ([M v]) decreased with the increased time from 0 to 30 min but increased when the duration prolonged to 45 min. The change of apparent viscosity with shear rate of all pectin solutions could be well described by Sisko model (R 2 ≥ .996) and the infinite‐rate viscosity (η ∞) and the consistency coefficient (k s) values decreased after ultrasonic treatment. Ultrasonic treatment could have an effect on dynamic moduli and activation energy of sugar beet pectin solutions. Particle size of pectin emulsions decreased and absolute zeta potential increased with increased time from 0 to 20 min. Excessive ultrasonic duration (30 and 45 min) could result in the aggregation of oil droplets in pectin emulsion and decrease in emulsifying stability. It could be concluded that ultrasonic treatment could affect the rheological and emulsifying properties of sugar beet pectin. The results have important implications for understanding the ultrasonic modification of sugar beet pectin., Different processing methods yielded bean sauces more distinguishable by appearance, taste, and mouth‐feel than by aroma, flavor, and after‐taste. Sauces that were brown in color, with burnt aroma and burnt after‐taste were preferred to those that were described as lumpy with mashed potato flavor. Oven roasted beans and boiled beans were preferred to traditionally roasted, extruded, and unprocessed beans.

This paper empirically investigates the impact of economic growth and industrial structure on China's Nitrogen Oxides (NOx) emissions reduction in a comprehensive Kaya-PLS framework. It is found that the influencing coefficients of economic growth and industrial structure are 0.27 and 2.53, respectively. It indicates that economic growth and industrial structure do bring positive effects on China's NOx emissions, and industrial structure plays a much greater role than economic growth in the process of NOx emissions reduction in China. Moreover, we incorporate additional variables involving energy consumption structure, energy intensity, population and cement production to augment the NOx emissions function. In addition, six scenarios are set to calculate China's NOx emissions for 2019–2030. The prediction results show that China's NOx emissions decreased by 9.11% on average during 2019–2030 because of the decline of the proportion of secondary industry. It means that the decrease of proportion of secondary industry would make a significant decrease for China's NOx emissions. What's more, China's NOx emissions in six scenarios in 2020 are not more than 15.74 million tons, indicating that it is realistic to achieve China's reduction target on NOx emissions according to the 13th Five-Year Plan. Therefore, the government should adjust the energy structure and industrial structure as soon as possible to control China's NOx emissions and improve air quality.

The corrosion behavior and passive film properties of CrMnFeCoNi and CrFeCoNi coatings in 0.5 mol/L H2SO4 solution were investigated by potentiodynamic and potentiostatic measurements, electrochemical impedance spectroscopy and Mott-Schottky tests. The chemical compositions of passive film were characterized by X-ray photoelectron spectroscopy (XPS). Results indicated that CrFeCoNi coating possessed lower passive current density, higher polarization resistance, lower donor and acceptor density compared with CrMnFeCoNi coating, which determined CrFeCoNi coating has higher corrosion resistance than CrMnFeCoNi coating. The excellent resistance to corrosion could be attributed to the structure and chemical compositions of passive film

Panax notoginseng is a widely used traditional Chinese medicine and has extensive pharmacological effects. In this work, water-soluble polysaccharides from Panax notoginseng were isolated and fractionated. One starch-like polysaccharide (PNPN) and six pectin fractions (PNPA-1A, PNPA-1B, PNPA-2A, PNPA-2B, PNPA-3A and PNPA-3B) were obtained. Monosaccharide composition, enzymatic hydrolysis, nuclear magnetic resonance and methylation analysis were combined to characterize their structures. PNPA-1A and PNPA-2A mainly contained 1,4-β-D-galactans, 1,5-α-L-arabinan and arabinogalactan II (AG-II). PNPA-3A was a typical rhamnogalacturonan I (RG-I) type pectin with 1,4-β-D-galactan and 1,5/1,3,5-α-L-arabinan side chains. PNPA-1B, PNPA-2B and PNPA-3B consisted of homogalacturonan (HG) as major domains, together with different ratios of RG-I and rhamnogalacturonan II (RG-II) domains. These results will provide basis for further investigation of structure-activity relationships of Panax notoginseng polysaccharides and be useful for the application of Panax notoginseng.

Summary Template effects are at the origin of supramolecular chemistry, but the behavior of folded molecules is a relatively new undertaking. Water-soluble cavitand hosts bind hydrocarbons through hydrophobic effects and force long-chain guests into folded conformations. This brings their ends closer together, and sites that were remote in solution become neighbors in the confined space and affect each other’s reactivity. Amphiphilic guests fold in the cavitand to bury hydrophobic surfaces and expose the hydrophilic surfaces to the bulk solution. This arrangement leads to product distributions in monofunctionalization reactions that are significantly altered from the statistically determined outcomes in solution. The cavitand also acts as a template for macrocyclic processes involving direct reaction of the guests’ ends. We propose applying the effects of folding in cavitands to truly remote functionalization reactions and provide access to molecules that cannot be made by conventional means.

We present a comprehensive composition analysis of calcium phosphate cements (CPCs) incorporating increasing amounts of bioactive pyrophosphate species (up to 17 wt% P2O7). These cements comprise p ...

PD98059 is a reversible MEK inhibitor that we are investigating as a potential treatment for neurochemical changes in the brain that drive neurohumoral excitation in heart failure. In a rat model that closely resembles human heart failure, we found that central administration of PD98059 inhibits phosphorylation of ERK1/2 in the paraventricular nucleus of the hypothalamus, ultimately reducing sympathetic excitation which is a major contributor to clinical deterioration. Studies revealed that the pharmacokinetics and biodistribution of PD98059 match a two-compartment model, with drug found in brain as well as other body tissues, but with a short elimination half-life in plasma (approximately 73 min) that would severely limit its potential clinical usefulness in heart failure. To increase its availability to tissues, we prepared a sustained release PD98059-loaded PLGA microparticle formulation, using an emulsion solvent evaporation technique. The average particle size, yield percent, and encapsulation percent were found to be 16.73 μm, 76.6%, and 43%, respectively. In vitro drug release occurred over 4 weeks, with no noticeable burst release. Following subcutaneous injection of the microparticles in rats, steady plasma levels of PD98059 were detected by HPLC for up to 2 weeks. Furthermore, plasma and brain levels of PD98059 in rats with heart failure were detectable by LC/MS, despite expected erratic absorption. These findings suggest that PD98059-loaded microparticles hold promise as a novel therapeutic intervention countering sympathetic excitation in heart failure, and perhaps in other disease processes, including cancers, in which activated MAPK signaling is a significant contributing factor. Graphical abstract.

Ceria has been used for catalyst support for long time due to its unique structural properties resulting from oxygen vacancies and reversible valence change (Ce4+ and Ce3+). In this report, ceria nanorods (NR) and nanocubs (NC) were prepared with hydrothermal method and 5 wt% nickel was loaded on it. The effect of morphology of ceria supports for CO2 methanation reaction was studied. Characterization including TPR, TEM, XRD and XPS shows that Ni/CeO2-NR had a higher number of Ce3+ proportion compared with Ni/CeO2-NC. Both catalysts showed high conversion and selectivity for methane at low temperature range at200–250 °C and interestingly Ni/CeO2-NR exhibited a higher activity than Ni/CeO2–NC. A kinetic study and DRIFTs investigation were carried out to formulate the mechanism. It turned out that CO2 methanation on Ni/CeO2 goes through a formate route instead of CO2 dissociation and the oxygen vacant sites are supposed to be the active sites for the formate formation in this mechanism.

Storing hydrogen efficiently in condensed materials is a key technical challenge. Tremendous efforts have been given to inorganic hydrides containing B–H, Al–H and/or N–H bonds, while organic compounds with a great variety and rich chemistry in manipulating C–H and unsaturated bonds, however, are undervalued mainly because of their unfavourable thermodynamics and selectivity in dehydrogenation. Here, we developed a new family of hydrogen storage material spanning across the domain of inorganic and organic hydrogenous compounds, namely metallo-N-heterocycles, utilizing the electron donating nature of alkali or alkaline earth metals to tune the electron densities of N-heterocyclic molecules to be suitable for hydrogen storage in terms of thermodynamic properties. Theoretical calculations reveal that the enthalpies of dehydrogenation (ΔHd) of these metallo-N-heterocycles are dependent on the electronegativity of the metals. In line with our calculation results, sodium and lithium analogues of pyrrolides, imidazolides and carbazolides of distinct structures were synthesized and characterized for the first time, where the cation-π interaction was identified. More importantly, a reversible hydrogen absorption and desorption can be achieved over lithium carbazolide which has a hydrogen capacity as high as 6.5 ​wt% and a suitable enthalpy of dehydrogenation of 34.2 ​kJ ​mol−1-H2 for on-board hydrogen storage.

This paper investigated the combustion instability of spanwise positions in a hydrogen fueled scramjet combustor with a cavity flame holder. High-speed OH-PLIF technique was performed on a direct-connect supersonic combustion facility, and dynamic mode decomposition (DMD) as postprocessing. Combustion instability was investigated by characterizing the dominant frequencies and growth factors. By changing the equivalence ratio of hydrogen, the peak frequencies of scramjet mode and ramjet mode were obtained. Scramjet mode tended to have small oscillation at 150–200 Hz reflected by negative growth factors due to the stable flame structure. At ram-to-scram transition, oscillations at 80–120 Hz were remarkably enhanced due to the positive growth factors. In ramjet mode, the large differences of frequency characteristics in spanwise positions were observed. The dominant DMD modes near the cavity wall appeared to have negative growth factors leading to a stable flame with small oscillations. Besides, the characteristics of frequency-shift were affected by the positions of injector.

In the present work, the geometry, electronic structure, and infrared spectra (IR) of meso-tetra-substituted porphyrin have been investigated theoretically. The optimization of geometries and electronic structure calculations of meso-tetraphenylporphyrin (TPP) and meso-tetra(3-pyridyl)porphyrin (T3PyP) are performed on the basis of density functional theory. The substitution of pyridyl for phenyl in meso-tetra-substituted porphyrins can result into the reduction of molecular size, including the molecular diameter, as well as the size of the central ring of porphin. It has also been found that the molecular orbital energies of T3PyP are smaller than the counterparts of TPP whereas there is almost no change in the HOMO–LOMO gap. Additionally, the infrared spectrum of TPP and T3PyP has been compared in order to determine whether there is a red shift or a blue shift.

In abrasive waterjet (AWJ) process, abrasive properties are of critical factors that influence machining performances. Abrasive process parameters including abrasive material, size and flow rate, exert a significant impact on cutting ability and quality of AWJ. In this paper, monolithic abrasive material (garnet, alumina and silicon carbide) and corresponding mixing abrasive materials are adopted to evaluate the effect of abrasive process parameters on the cutting ability and quality, respectively. Two kinds of cutting experiments are conducted with a monolithic abrasive to explore the influence of variation in abrasive material, size and flow rate on the machining performance. The cutting depth experiments for evaluating the cutting ability in terms of cutting depth are conducted with a right trapezoid aluminium alloy block. The kerf cutting experiments are taken to evaluate the cutting quality by the kerf taper angle, kerf width and surface roughness. On this basis, AWJ experiments with mixing abrasive materials are taken to probe into the composition of mixing abrasives’ effect on cutting performance. It is found that the abrasives consisting of 75% alumina and 25% garnet in mass fraction lead to a maximum cutting depth of 41.7 mm and the smallest surface roughness of Ra 2.1 μm under the flow rate of 130 g/min.

The oxygen reduction reaction (ORR) plays an irreplaceable role in many energy-conversion processes. Low-cost catalysts with high activity and stability are eagerly needed to improve the sluggish O...

For the development of advanced flexible and wearable electronic devices, functional electrolytes with excellent conductivity, temperature tolerance, and desirable mechanical properties need to be engineered. Herein, an alkaline double-network hydrogel with high conductivity and superior mechanical and antifreezing properties is designed and promisingly utilized as the flexible electrolyte in all-solid-state zinc-air batteries. The conductive hydrogel is comprised of covalently cross-linked polyelectrolyte poly(2-acrylamido-2-methylpropanesulfonic acid potassium salt) (PAMPS-K) and interpenetrating methyl cellulose (MC) in the presence of concentrated alkaline solutions. The covalently cross-linked PAMPS-K skeleton and interpenetrating MC chains endow the hydrogel with good mechanical strength, toughness, an extremely rapid self-recovery capability, and an outstanding antifatigue property. Gratifyingly, the entrapment of a concentrated alkaline solution in the hydrogel matrix yields an extremely high ionic conductivity (105 mS cm-1 at 25 °C) and an excellent antifreezing capacity. The hydrogel retains comparable conductivity and eligible strength to withstand various mechanical deformations at -20 °C. The all-solid-state zinc-air batteries using PAMPS-K/MC hydrogels as flexible alkaline electrolytes exhibit comparable values of specific capacity (764.7 mAh g-1), energy capacity (850.2 mWh g-1), cycling stability, and mechanical flexibility. The batteries still possess competitive electrochemical performances even when the operating temperature drops to -20 °C.

The thermal conductivity (TC) of gutta-percha, zinc oxide, and carbon nanotubes nanocomposites (GP/ZnO@CNTs) is improved greatly by the oriented CNTs, which is induced by shear field of the capillary rheometer. Furthermore, the effects of shear rate and temperature on the orientation of CNTs and the TC of the nanocomposites are investigated. The results of Raman show that the degree of orientation of CNTs increases with the increment of shear rate and/or temperature, which greatly improves the thermal conductance of the nanocomposites when the orientation degree is equal to 10.8. Compared with the GP/ZnO@CNTs nanocomposites with random CNTs, the highest TC of GP/ZnO@CNTs nanocomposites with oriented CNTs is increased by 81.2%, which is up to 2.50 W m−1K−1.

Given the unique properties of sewage sludge-derived carbonaceous materials (SC) and the correlation of SC with recycling sewage sludge in an efficiently safe way, there is significant attraction f...

Flow battery technology offers a promising low-cost option for stationary energy storage applications. Aqueous zinc–nickel battery chemistry is intrinsically safer than non-aqueous battery chemistry (e.g. lithium-based batteries) and offers comparable energy density. In this work, we show how combining high power density and low-yield stress electrodes can minimize energy loss due to pumping, and have demonstrate methods to achieve high energy and power density for ZnO/Ni(OH)2 electrodes by changing composition and optimizing testing protocols. Firstly, mechanically stable and homogeneous Ni(OH)2/carbon and ZnO/Zn flowable electrodes in 7 M KOH electrolyte were designed using a microgel dispersion as the suspending matrix. By determining the critical volume fractions for conductivity percolation, colloidal suspensions with 6.2 vol% of carbon and 23.1 vol% of Zn were selected for preparing catholytes and anolytes to ensure that these semi-solid electrodes possess high voltage and high coulombic efficiencies. The resulting flowable electrodes exhibited non-Newtonian rheology with a yield stress of approximately ∼200 Pa, which assists in maintaining mechanical stability of the suspensions. An energy density of up to 134 W h Lcatholyte−1 and power density up to ∼159 mW cmgeo.−2 was demonstrated for semi-solid ZnO/Ni(OH)2 electrodes, and coulombic efficiency of 94% was achieved during cycling by optimizing the charging protocol to 60% SOC of Ni(OH)2. Lastly, semi-solid ZnO and Ni(OH)2 flow cells were built and tested using an intermittent mode of operation. The high energy and power densities, high coulombic efficiency, and negligible pumping loss of the Zn–Ni semi-solid electrodes developed in the present work present a promising system for further development.

Usually, Al-Ga alloys are prepared by heating materials to hundreds of degrees for a long time, and the alloys obtained are in the solid state. Although some Ga-rich liquid Al-Ga composites have been developed lately, the mass percentage of Al is small, due to which the hydrogen generation rate and efficiency are limited. Besides, an alkaline solution is indispensable in these studies, which is also a limitation. In this paper, a semisolid Al-Ga composite has been fabricated by mixing liquid gallium and fragmented aluminium foils at room temperature, which is an effective means to generate hydrogen from pure water. With the increase in the Al proportion, the mixture changes from a liquid to a cement-like semisolid material morphologically. Furthermore, an application of the fuel cell taking advantage of the hydrogen released from the composites is given. This method does not require a high-temperature device and only requires water to produce hydrogen once the semisolid Al-Ga composite material is fabricated. Therefore, this is a new approach for making more portable and safer devices for hydrogen production.

Carbon nanofibers (CNFs) were prepared by electrospinning, and silver (Ag) ions were grown on the surface of the CNFs by in situ solution synthesis. The structure and morphology of obtained Ag-doped CNFs (Ag-CNFs) were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The gas sensibility of the composite fiber was investigated by ammonia (NH3) obtained by natural volatilization from 1 to 4 mL of NH3 solution at room temperature. It was found that the fibers exhibited a sensitive current corresponding to different NH3 concentrations and a greater response at high concentrations. The sensing mechanism was discussed, and the good absorptivity was demonstrated. The results show that Ag-CNF is a promising material for the detection of toxic NH3.

Silicon germanium (SiGe) alloys hold promise for thermoelectric power generation at high temperatures and have been applied in deep-space missions. However, enhancement of the dimensionless thermoelectric figure-of-merit (ZT) is still needed for practical civil applications of SiGe. In this work, we report high-performance oxide/SiGe bulk composites that were obtained via hot-press sintering of mixed powders composed of phosphorus (P)-doped SiGe prepared via mechanical alloying, using a ball-milling technique and La-Nb-doped SrTiO3 (La-Nb-STO). The La-Nb-STO powder was obtained from ball milling of a bulk La-Nb-STO sample that was sintered via hot pressing of hydrothermally synthesized La-Nb-STO powder. Controlling the amount of La-Nb-STO nanoparticles added to SiGe matrix increased the power factor by optimizing the electron concentration and mobility in the composite. In addition, compared with single-phase P-doped SiGe, the second phase decreased the thermal conductivity because of additional phonon scattering at the interface. As a result, a high ZT of 0.91 was realized in the n-type oxide/SiGe bulk composite at 1000 K, which was 18% larger than that for the typical materials used in space flight missions and 5% higher than the single-phase SiGe alloys obtained in the present study. The strategy used in this study could also be viable to further enhance the ZT of nanostructured n-type SiGe and SrTiO3-based oxide materials.

In order to effectively deal with large amounts of complex organic pollutants in the harmful distillation residues with low energy consumption, a novel two-stage fluid-bed/fixed-bed system was designed to catalyze oxidation of acrylic acid production residue. The effects of fluid-bed temperature, gaseous hourly space velocity (GHSV), and oxygen excess rate on the purification of acrylic acid production residue in the two-stage fluid-bed/fixed-bed system were studied to prove the feasibility of the method. The chemical oxygen demand (COD) of the discharged liquid was

With reduced dehydrogenation enthalpy change and reduced dehydrogenation temperature compared with its phenol-cyclohexanol pair, sodium phenoxide-cyclohexanolate pair developed recently is promising for large-scale energy storage and long-distance hydrogen transportation. In the present work, we investigate the kinetic behavior of the pair in the hydrogenation and dehydrogenation in water over three commercial catalysts. It is shown that 5% Ru/Al2O3 and 5% Pt/C perform well in the hydrogenation and dehydrogenation, respectively. Kinetic analyses show that the hydrogenation of sodium phenoxide is of first-order with respect to H2 pressure and zero-order to the concentration of sodium phenoxide in the presence of Ru/Al2O3 catalyst. >99% conversion of cyclohexanol and >99% selectivity to phenoxide can be achieved in the dehydrogenation catalyzed by Pt/C catalyst and in the presence of NaOH at 100 °C, where cyclohexanone was observed as an intermediate. According to the kinetic analysis, the hydrogenation of sodium phenoxide may undergo the hydrolysis and hydrogenation pathway. For the dehydrogenation, an intermediate, i.e., cyclohexanone, was detected and two possible pathways are proposed accordingly.

From a suite of advanced magic-angle spinning (MAS) NMR spectroscopy and powder X-ray diffraction (PXRD) experiments, we present a comprehensive structural analysis of pyrophosphate-bearing calcium ...

Design of hollow carbon structure by using metal-organic-frameworks (MOFs) precursors has come under the spotlight in electrochemical energy related applications due to its structure advantages. Here, a bimetal-based MOF (Zn and Fe) is adopted to synthesize hollow carbon nanobox with encapsulation of FeP nanoparticles. An unique core-shell architecture consisting of Zn-Fe Prussian blue analogue (PBA) core and polydopamine shell is first synthesized, followed by pyrolysis-oxidation-phosphorization process to prepare monodispersed FeP nanoparticles encapsulated in hollow carbon nanobox (denoted as FeP/HCNB). Electrochemical hydrogen evolution activity is chosen to investigate the structure advantage of FeP/HCNB. It achieves overpotentials of −88 mV and −180 mV at 10 mA cm−2 in acidic and alkaline solutions, respectively, and continuous operation for 15 h (start at 20 mA cm−2). It is therefore expected that the synthetic strategy of nanobox would enlighten the preparation of various nanostructures for different applications.

In the present work, Zn-incorporated TiO2 coatings are prepared through a one-step micro-arc oxidation (MAO) method on a grade 4 pure titanium with the addition of either Na2Zn-EDTA solution or ZnO nanoparticles (NPs) as Zn sources. The microstructural features of both Zn-incorporated TiO2 coatings were systematically examined. It is revealed that different Zn sources result in significant difference of phase component, chemical state, composition and morphology between the resultant Zn-incorporated MAO coatings. Zn species could be present as ZnO and Zn(OH)2 in the coating when Na2Zn-EDTA was used as Zn source whereas the presence of ZnO nano-clusters is obvious on the coating surface with ZnO NPs as Zn source. The addition of ZnO NPs during the MAO process also leads to a lower Zn content of the resultant coating, which is more defective with increased thickness in comparison to that of Na2Zn-EDTA. Further, antibacterial property and osteogenic activity of both Zn-incorporated coatings were examined. Both Zn-incorporated coatings exhibit favourable bacterial inhibition ability and bone formability, suggesting the successful synthesis of bifunctional coatings through the facile one-step micro-arc oxidation method.

From a large ensemble of 34 silicate-based glasses from the borosilicate, phosphosilicate, and borophosphosilicate systems that comprise either Na as a sole glass-network modifier or when mixed wit ...

Fundamental characteristics of hydrogen flame in diluted atmosphere may have important guiding value for controlling the operation of argon-circulated hydrogen engines. In this paper, the impact of thermal-atmosphere (T ≥ 940 K, N2/O2, Ar/O2 and CO2/O2) on the flame characteristics of hydrogen jet were investigated experimentally and numerically based on a controllable active thermal-atmosphere burner. The effects of different diluents on flame liftoff height and luminosity were quantitatively analyzed and the different luminosity of the hydrogen jet flame under different dilution gas atmosphere was explained with the chemical reaction kinetics. Different critical temperatures exist in different atmospheres. The flame luminosity is in the increasing order of CO2/O2-, Ar/O2- and N2/O2-atmosphere. The analysis speculates that CO2* is generated in the flame of CO2/O2-atmosphere. The difference in axial velocity and mixture fraction under different dilution gas atmospheres is mainly influenced by the thermal atmosphere and the physical properties of the dilution gas, which also has a great influence on the jet before the autoignition occurs.

Groundwater treatment sludge is an industrial waste that is massively produced from groundwater treatment plants. Conventional methods for treatment of this sludge, such as discharge into deep wells or the sea, or disposal at landfills, are not environmentally sustainable. Here, we demonstrate an alternative strategy to recycle the sludge by preparing a magnetic maghemite adsorbent via a one-step hydrothermal method with NaOH solution as the only solvent. With this method, the weakly magnetized sludge, which contained 33.2% iron (Fe) and other impurities (e.g., silicon (Si), aluminum (Al), and manganese (Mn)), was converted to magnetic adsorbent (MA) with the dissolution of Si/Al oxides (e.g., quartz and albite) into the liquid fraction. At a NaOH concentration of 2 mol·L−1, approximately 18.1% of the ferrihydrite in the Fe oxides of the sludge was converted into 11.2% maghemite and 6.9% hematite after the hydrothermal treatment. MA2 (i.e., MA produced by a 2 mol·L−1 NaOH concentration) exhibited a good magnetic response of 8.2 emu·g−1 (1 emu = 10−3 A·m2), and a desirable surface site concentration of 0.75 mmol·g−1. The synthesized MA2 was used to adsorb the cationic pollutant tetracycline (TC). The adsorption kinetics of TC onto MA2 fitted well with a pseudo-second-order model, and the adsorption isotherms complied well with the Langmuir model. The maximum adsorption capacity of MA2 for TC was 362.3 mg·g−1, and the main mechanism for TC adsorption was cationic exchange. This study is the first to demonstrate the preparation of an MA from recycled sludge without a reductant and/or exogenous Fe source. The prepared adsorbent can be used as a low-cost adsorbent with high capacity for TC sorption in the treatment of TC-containing wastewater. Keywords: Groundwater treatment sludge, Maghemite, Cationic exchange, Adsorption, Tetracycline

The next generation of high-performance flexible electronics has put forward new demands on the development of ionic conductive hydrogels. In recent years, many efforts have been made toward developing double-network (DN) hydrogels due to their excellent mechanical properties and unique network structures. However, profound challenges remain in achieving controllable surface morphology and multifunctional integration within DN hydrogels. In this work, we report the fabrication of a multifunctional DN hydrogel by multiple cross-linking between an innovative K+-containing poly(ionic liquid) (PIL) and κ-carrageenan. The resulting hydrogel possesses fascinating physicochemical properties, ranging from remarkable mechanical properties and machinability to adjustable surface morphology and superior adhesion ability. The extremely versatile DN hydrogels exhibited outstanding potential for the future of wearable strain sensors in real-time monitoring of human health, and the optimized design strategy opens new possibilities for the fabrication of multiscale structured and multifunctional integrated ionic conductive hydrogels.