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This study investigated the effects of Moringa oleifera polysaccharide (MOP) on serum immune indices, immune organ indices, colonic microflora and immune repertoire of mice. Forty male SPF C57BL/6 mice were randomly divided into four groups and subjected to gavage of 0, 20, 40 and 60 mg/kg MOP for 28 days. Mice were sacrificed on the last day of the experiment and their thymus, spleen, blood and colon contents were collected for further detection. Our findings suggested that MOP could significantly increase the thymus index (P 0.01) and spleen index (P 0.05), and significantly decrease the levels of interleukin-6 and tumour necrosis factor-α in mice (P 0.05). And MOP could regulate the proportion of colonic microflora of mice, significantly increase the abundance of Muribaculaceae and significantly decrease the abundance values of Proteobacteria, Helicobacter, Stenotrophomonas, etc (P 0.05). In addition, MOP could regulate the usage frequencies of TRBV15 (P = 0.06) and TRBV9 (P = 0.10) on the TCRα chain and 9 V-J pairs were found to have remarkable usage frequency changes. These results implied that MOP exerted positive effects on the immune performance and intestinal health of mice.

The fundamentals, standardization, innovative strategies, and future direction of low-temperature water electrolysis including alkaline (AWE), proton exchange membrane (PEMWE), and anion exchange membrane (AEMWE) water electrolyses are discussed.

This study investigated the effects of Moringa oleifera polysaccharides (MOP) on the serum indexes, small intestinal morphology, small intestinal metabolic profile, and caecal microbiota of mice. A new type of polysaccharides with 104,031 Da molecular weight and triple helix structure was isolated from M. oleifera leaves for in vivo experiment. Forty male SPF C57BL/6 mice aged 4 weeks were average divided into four groups randomly according to the MOP gavaged daily (0, 20, 40 and 60 mg/kg body weight MOP). After a 7-day preliminary trial period and a 28-day official trial period, the mice were slaughtered. Results showed that MOP reduced glucose, total cholesterol, and malondialdehyde. It also improved superoxide dismutase and catalase in serum (P < 0.05). For small intestinal morphology, MOP improved the villi length and crypt depth in both ileum and jejunum (P < 0.05); the ratio of villi length to crypt depth in jejunum increased (P < 0.05). MOP could cause the increase of beneficial bacteria and the decrease of harmful bacteria in caecum, further affecting the function of microbiota. In addition, MOP regulated 114 metabolites enriched in the pathway related to the synthesis and metabolism of micromolecules. In sum, MOP exerted positive effects on the serum indexes and intestinal health of mice.

Solar thermochemical hydrogen generation (STCH) is a promising approach for eco-friendly H2 production, but conventional STCH redox compounds often suffer from thermodynamic and kinetic limitations with limited tunability. Expanding from the nascent high-entropy ceramics field, this study explores a new class of compositionally complex perovskite oxides (La0.8Sr0.2)(Mn(1-x)/3Fe(1-x)/3CoxAl(1-x)/3)O3 for STCH. In situ X-ray diffraction demonstrates the phase stability during redox cycling and in situ X-ray photoelectron spectroscopy shows preferential redox of Co. The extent of reduction increases, but the intrinsic kinetics decreases, with increased Co content. Consequently, (La0.8Sr0.2)(Mn0.2Fe0.2Co0.4Al0.2)O3-{\delta} achieves an optimal balance between the thermodynamics and kinetics properties. The combination of a moderate enthalpy of reduction, high entropy of reduction, and preferable surface oxygen exchange kinetics enables a maximum H2 yield of 395 +- 11 {\mu}mol g-1 in a short 1-hour redox duration. Entropy stabilization expectedly contributes to the structure stability during redox without phase transformation, which enables an exceptional STCH stability for >50 cycles under harsh interrupted conditions. The underlying redox mechanism is further elucidated by the density functional theory based parallel Monte Carlo computation, which represents a new computation paradigm first established here. This study suggests a new class of non-equimolar compositionally complex ceramics for STCH and chemical looping.

The present study investigated the effects of malic acid, sucrose, and their mixture on the fermentation parameters, Cornell Net Carbohydrate and Protein System (CNCPS) nitrogen fractions, and bacterial community of Moringa oleifera leaves (MOL) silages. The trial was divided into four treatments and labeled as CON (control group) and MLA, SUC, and MIX (respectively denoting the addition of 1% malic acid, 1% sucrose, and 1% malic acid + 1% sucrose to the fresh weight basis). The silage packages were opened on the 2nd, 5th, 10th, 20th, and 40th days of ensiling for subsequent determination. Malic acid and sucrose increased the lactic acid content (p &lt, 0.05) and pH value, and the acetic acid contents of MLA and MIX were lower than those in CON (p &lt, 0.05). Compared with sucrose, malic acid had a better capacity to preserve nutrients and inhibit proteolysis, and thus exerted better effects on the CNCPS nitrogen fractions. The results of 16S rRNA showed that the dominant phyla were Firmicutes and Proteobacteria and that the dominant genera were Lactobacillus and Weissella. With the application of silage additives and the processing of fermentation, there was a remarkable change in the composition and function of the bacterial community. The variation of the fermentation parameters and CNCPS nitrogen fractions in the MOL silages caused by malic acid and sucrose might be attributed to the dynamic and dramatic changes of the bacterial community.

Solid oxide steam electrolysis cell, a promising electrical-chemical conversion device for the next generation efficient hydrogen production and energy storage, has been actively studied because of their high energy conversion efficiencies and prospective applications as electrochemical reactors. After decades of research on protonic ceramic materials, remarkable advances have been made in the protonic ceramic electrochemical cells (PCECs) air electrode and electrolyte. However, the existing air electrodes are far from satisfying the requirements of practical applications, a series of issues, including the lack of active and durable electrodes, greatly limit the commercialization. To date, the systematic development of triple conducting catalysts remains abstruse because of the challenges of characterizing protonic behavior. A quantitative properties assessment and prediction on protonic properties of perovskite are still not available. Starting with a computational fluid dynamic modeling on the protonic ceramic electrochemical cells (PCECs) air electrode, we focused on the materials design of air electrode materials by employing model guidance, operating durability optimization by electrode structure engineering, as well as the air electrode surface tailoring to overcome the most rate-limiting step. Thus, the electrochemical performance and durability of PCEC care comprehensively improved. The fabrication methods, characterization techniques with electrochemical performance are presented. Further work plans and implications are proposed regarding optimizing the structure of materials, preparation technology, and better understanding the role of these triple conductors. This research is expected to provide an in-depth understanding and offer avenues in the rational design of PCEC with long operational life and high energy/power density in the near future.

For the first time, proton conductors BaZr0.1Ce0.7Y0.1Yb0.1O3−δ (BZCYYb) and La2Ce2O7 (LCO) are combined to create an interface active and steam-tolerant electrolyte for high-performance proton-con...

Triple-conducting materials have been proved to improve the performance of popular protonic ceramic electrolysis cells. However, partially because of the complexity of the water-splitting reaction involving three charge carriers, that is, oxygen (O2-), proton (H+), and electron (e-), the triple-conducting reaction mechanism was not clear, and the reaction conducting pathways have seldom been addressed. In this study, the triple-conducting Ruddlesden-Popper phase Pr1.75Ba0.25NiO4+δ as an anode on the BaCe0.7Zr0.1Y0.1Yb0.1O3-δ electrolyte was fabricated and its electroresponses were characterized by electrochemical impedance spectroscopy with various atmospheres and temperatures. The impedance spectra are deconvoluted by means of the distribution of the relaxation time method. The surface exchange rate and chemical diffusivity of H+ and O2- are characterized by electrical conductivity relaxation. The physical locations of electrochemical processes are also identified by atomic layer deposition with a surface inhibitor. A microkinetics model is proposed toward conductivities, triple-conducting pathways, reactant dependency, surface exchange and bulk diffusion capabilities, and other relevant properties. Finally, the rate-limiting steps and suggestions for further improvement of electrode performance are presented.

The role of molybdenum in the interaction of the composed phases of 2205 duplex stainless steel (DSS) in the 3.5-wt% NaCl solution was investigated, by comparing the untreated 2205 DSS sample with two single-austenite and single-ferrite samples prepared via selective dissolution. The results demonstrate that, the interaction is beneficial to the whole passive film properties of 2205 DSS by promoting both the γ-phase and α-phase. The passivity of 2205 DSS at high potential strongly depends on the protective ability of Mo species. Compared with α-phase and γ-phase, Mo species of the 2205 DSS are more capable of keeping stable and being beneficial to passive film recovery, which make 2205 DSS show enhanced performance in pitting resistance and repassivation.

Electron, proton and oxygen-triple-conducting materials are becoming the dominant steam electrode candidate to break the rate limit on the water-splitting reaction that throttles the performance of protonic ceramic electrolysis cells (PCECs). In this study, based on Pr2NiO4+δ Ruddlesden-Popper phase, we manipulate these conductivities by Pr-site Ba substitution to probe the correlation of each conductivity with the kinetics of the elementary reaction steps. It is found that the proton conductivity is vital to sustain an extended active surface area for faster adsorption of reactants and desorption of products. The effect of oxygen conductivity is surprisingly found insignificant in the water-splitting reaction. On the contrary, surface oxygen removal is discovered as the most rate-limiting process. The electronic conductivity is not a direct limiting factor. However, an electron transfer process between the current collector and the electrode junction could introduce extra resistance that is perceptible at a high operating temperature range. The best water-splitting activity is obtained on a proton conductivity/oxygen surface desorption capability well-balanced sample after Ba substitution. As a result, a water-splitting reaction resistance of 0.022 Ωcm2, a current density of 1.96 A/cm2 at 700 °C is achieved on Pr1.7Ba0.3NiO4+δ, one of the best performances for PCECs.

This study investigated the effects of lycopene on the gene expression profile and expression of genes related to fat metabolism of Xinghua breeding hens. Seven hundred and twenty healthy breeding hens were randomly assigned to four treatments; each treatment was replicated six times with 30 hens each. Broken rice and soybean meal were adopted for the basal diet and added with 0 (control group), 20, 40 and 80 mg/kg lycopene respectively. Gene expression profile of the liver induced by lycopene and expression of genes related to fat metabolism in hens liver and intestine were analysed after 42-day feeding trial including 7-day pre-feeding period and 35-day formal period. The genes involved in fat metabolism were analysed, and we found that lycopene significantly increased the expression of PGC1α, PPARα, RXRα and RARα in the liver, PPARγ, RXRα and RXRγ in the jejunum, and RARα in the duodenum (p < .05); reduced the expression of FABP1 and FABP10 in the liver, and FATP4 in the jejunum (p < .05). By analysing gene expression profile, 158 differentially expressed genes (DEGs) including 69 up-regulated genes and 89 down-regulated genes were obtained between control group and 40 mg/kg group. KEGG pathway analysis was performed on all DEGs, and 5 pathways were obtained. In conclusion, lycopene can affect the expression of related genes, and this may be one of the reasons that lycopene can regulate fat metabolism.

In this study, we report a high performance and redox-stable symmetrical solid oxide fuel cell (SOFC) based on (Ba0.5Sr0.5) (Mo0.1Fe0.9)O3-δ (BSMF) electrode and La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) electrolyte. BSMF is able to operate both as anode and cathode. Excellent electrocatalytic activity has been achieved on BSMF towards hydrogen oxidation and oxygen reduction. Due to its closely matched lattice parameter to LSGM electrolyte, a unique diffuse interface is formed between BSMF and LSGM. Compared to a clean interface, e.g. BSMF/gadolinium doped ceria interface, this diffuse interface promotes the performance of BSMF electrode 1–1.8 times in 600–800 °C. Polarization resistance of the BSMF/LSGM specimen is as low as 0.047 and 0.007 Ωcm2 in humidified H2 and in air at 800 °C, respectively. On the BSMF/LSGM/BSMF symmetrical cell, a maximum power density of 2.28 W/cm2 is achieved at 800 °C, the highest among with redox-stable ceramic electrodes to the best of our knowledge. Redox stability of this cell is confirmed. The role of anode and cathode is reversed back and forth in different operation modes. No apparent degradation is observed through 4 cycles within a 110 h operation period. These findings demonstrate that (Ba0.5Sr0.5) (Mo0.1Fe0.9)O3-δ coupled with LSGM electrolyte is an excellent choice to build a high performance, redox-stable SOFC.

The rechargeable aqueous zinc-ion batteries (ZIBs) based on the Zn/MnO2 couple and mildly acidic electrolyte have emerged as promising large-scale energy storage systems. This work reports an in situ electrochemical activation approach to oxidizing MnS into an electrochemically derived oxide (MnS-EDO), which unlocks its potential as high-performance cathodes for ZIBs. MnS-EDO contains fragmented layers with abundant defects and thus demonstrates large electrochemically active surface areas, high electrochemical reactivity, fast ion diffusion kinetics, accelerated charge transfer and exceptional structural robustness during cycling compared to α-MnO2. MnS-EDO exhibits a specific capacity of 335.7 mAh g−1 with ~100% capacity retention after 100 cycles at 0.3 A g−1, outstanding rate capability and long-term stability retaining 104 mAh g−1 after 4000 cycles at 3 A g−1. This work elucidates the underlying electrochemical insights and a hybrid discharge mechanism involving homogeneous Zn2+ intercalation at ~1.4 V and subsequent heterogeneous reactions of insertion of both H+ and Zn2+ at ~1.25 V. The ambiguities among Zn buserite, birnessite and zinc hydroxide sulfate are clarified. This work provides a simple and low-cost approach to unlocking the potential of MnS-EDO cathode for promising aqueous rechargeable ZIBs and sheds light on a mechanistic understanding of manganese oxide-based cathodes.

uIn situ exsolution of nanoparticles is widely considered as an efficient and cost-effective method for increasing the number of active sites and consequently the catalytic activity on ceramic anodes in solid oxide fuel cells (SOFCs). In this study, by doping on the A-site of Sr2Fe1.5Mo0.5O6-delta (SF1.5 M), evenly distributed Fe nanoparticles (similar to 100 nm) were exsolved on the La0.5Sr1.5Fe1.5Mo0.5O6- delta (LSFM) surface under a typical anode operating environment (humidified H-2, 800 degrees C). In addition, the exsolution-dissolution reversibility of the exsolved Fe nanoparticles was observed during a redox cycle. Electrical conductivity relaxation (ECR) analysis demonstrated that the surface reaction kinetics on the LSFM anode is enhanced by in situ exsolution. Based on electrochemical impedance spectroscopy (EIS) and distribution of relaxation time (DRT) analysis, the perovskite structure was not damaged by the exsolution or the surface phase transition. During exsolution, the ionic conductivity increased. The higher surface catalytic activity and faster oxygen transportation led to enhanced electrochemical performance.

Proton-conductors BaZr0.1Ce0.7Y0.1Yb0.1O3-δ (BZCYYb) and La2Ce2O7 (LDC) are combined to create an interface active and steam-tolerant electrolyte for high-performance proton-conducting solid oxide electrolysis cells. LDC shows good chemical compatibility with BZCYYb. The readily fabricated LDC/BZCYYb bilayer electrolyte can be densified at a temperature as low as 1300oC vs. ~1600oC for the benchmark vapor-stable BaZr0.8Y0.2O3-δ electrolyte. With Pr2NiO4+δ as the anode and Ni as the cathode catalyst, this bilayer electrolyte cell yields a current density of 975 mA/cm2 and 300 mA/cm2 under a 1.3 V applied potential at 700oC and 600oC, respectively. This performance is among the best of all H-SOECs equipped with a chemically stable electrolyte so far. BZCYYb layer in the bilayer electrolyte promotes the hydrogen evaluation reaction at the cathode side, resulting in a 108% improvement over the cell without this layer. The LDC layer, on the other hand, effectively protects this functional BZCYYb layer from high concentration of vapor in a practical SOEC operation condition. The cell without LDC layer shows degradation in terms of increase in the electrolyzing potential from 1.07 V to 1.29 V during a 400 mA/cm2 operation at 700oC. In contrast, the bilayer electrolyte cell maintains the same electrolyzing potential of 1.13 V under the same conduction for a 102 h operation. These findings demonstrate that this synergic bilayer electrolyte design could be a vital strategy to overcome the dilemma between performance and stability faced by the current benchmark Zr- or Ce-rich Ba(CeZr)O3-δ electrolytes, achieving good performance and stability at the same time.