Interfacial Electronic Modulation of Dual-Monodispersed Pt–Ni_(3)S_(2) as Efficacious Bi-Functional Electrocatalysts for Concurrent H_(2) Evolution and Methanol Selective Oxidation

Constructing the efficacious and applicable bifunctional electrocatalysts and establishing out the mechanisms of organic electro-oxidation by replacing anodic oxygen evolution reaction(OER) are critical to the development of electrochemicallydriven technologies for efficient hydrogen production and avoid CO_(2) emission. Herein, the hetero-nanocrystals between monodispersed Pt(~ 2 nm) and Ni_(3)S_(2)(~ 9.6 nm) are constructed as active electrocatalysts through interfacial electronic modulation, which exhibit superior bi-functional activities for methanol selective oxidation and H_(2) generation. The experimental and theoretical studies reveal that the asymmetrical charge distribution at Pt–Ni_(3)S_(2) could be modulated by the electronic interaction at the interface of dual-monodispersed heterojunctions, which thus promote the adsorption/desorption of the chemical intermediates at the interface. As a result, the selective conversion from CH_(3)OH to formate is accomplished at very low potentials(1.45 V) to attain 100 m A cm^(-2) with high electronic utilization rate(~ 98%) and without CO_(2) emission. Meanwhile, the Pt–Ni_(3)S_(2) can simultaneously exhibit a broad potential window with outstanding stability and large current densities for hydrogen evolution reaction(HER) at the cathode. Further, the excellent bi-functional performance is also indicated in the coupled methanol oxidation reaction(MOR)//HER reactor by only requiring a cell voltage of 1.60 V to achieve a current density of 50 m A cm^(-2) with good reusability.

Targeted regeneration and upcycling of spent graphite by defect‐driven tin nucleation

The recycling of spent batteries has become increasingly important owing to their wide applications,abundant raw material supply,and sustainable development.Compared with the degraded cathode,spent anode graphite often has a relatively intact structure with few defects after long cycling.Yet,most spent graphite is simply burned or discarded due to its limited value and inferior performance on using conventional recycling methods that are complex,have low efficiency,and fail in performance restoration.Herein,we propose a fast,efficient,and“intelligent”strategy to regenerate and upcycle spent graphite based on defect‐driven targeted remediation.Using Sn as a nanoscale healant,we used rapid heating(~50 ms)to enable dynamic Sn droplets to automatically nucleate around the surface defects on the graphite upon cooling owing to strong binding to the defects(~5.84 eV/atom),thus simultaneously achieving Sn dispersion and graphite remediation.As a result,the regenerated graphite showed enhanced capacity and cycle stability(458.9 mAh g^(−1) at 0.2 A g^(−1) after 100 cycles),superior to those of commercial graphite.Benefiting from the self‐adaption of Sn dispersion,spent graphite with different degrees of defects can be regenerated to similar structures and performance.EverBatt analysis indicates that targeted regeneration and upcycling have significantly lower energy consumption(~99%reduction)and near‐zero CO2 emission,and yield much higher profit than hydrometallurgy,which opens a new avenue for direct upcycling of spend graphite in an efficient,green,and profitable manner for sustainable battery manufacture.

Cytological and Proteomic Analysis of Ginkgo biloba Pollen Intine

The pollen intine plays important roles in pollen germination and tube growth,but related information in Ginkgo biloba remains unclear.We isolated and obtained de-exined pollen from G.biloba.Using fluorescent probes,we observed the strongest cellulose fluorescence in the pollen intine.De-esterified pectin immunolabeled with JIM5 was present throughout the entire cell wall,whereas esterified pectin recognized by the monoclonal antibody JIM7 was concentrated in some regions.Callose staining with aniline blue was observed across the entire surface of the pollen intine.These results were confirmed by Fourier Transform InfraRed(FTIR)analysis.We also used proteomic approaches to identify different proteins between mature and de-exined pollen(48h after hydration)in vitro.Based on mass spectrometry,de-exined pollen had more proteins than mature pollen,including calmodulin,serine hydroxymethyltransferase,β-galactosidase 6,and class IV chitinase.According to Gene Ontology(GO)analysis,the differentially expressed proteins were mainly associated with transportation,defense reaction,sugar metabolism,energy metabolism,signal transduction,and cell wall formation.These findings suggest that most proteins involved in pollen germination and pollen tube growth are synthesized during pollen hydration,indicating the important role of pollen hydration in the reproductive process of G.Biloba.

A novel integrated non-targeted metabolomic analysis reveals significant metabolite variations between different lettuce (Lactuca sativa. L) varieties

Lettuce is an important leafy vegetable that represents a significant dietary source of antioxidants and bioactive compounds.However,the levels of metabolites in different lettuce cultivars are poorly characterized.In this study,we used combined GC×GC-TOF/MS and UPLC-IMS-QTOF/MS to detect and relatively quantify metabolites in 30 lettuce cultivars representing large genetic diversity.Comparison with online databases,the published literature,standards as well using collision cross-section values enabled putative identification of 171 metabolites.Sixteen of these 171 metabolites(including phenolic acid derivatives,glycosylated flavonoids,and one iridoid)were present at significantly different levels in leaf and head type lettuces,which suggested the significant metabolomic variations between the leaf and head types of lettuce are related to secondary metabolism.A combination of the results and metabolic network analysis techniques suggested that leaf and head type lettuces contain not only different levels of metabolites but also have significant variations in the corresponding associated metabolic networks.The novel lettuce metabolite library and novel non-targeted metabolomics strategy devised in this study could be used to further characterize metabolic variations between lettuce cultivars or other plants.Moreover,the findings of this study provide important insight into metabolic adaptations due to natural and human selection,which could stimulate further research to potentially improve lettuce quality,yield,and nutritional value.

Bullet-like vanadium-based MOFs as a highly active catalyst for promoting the hydrogen storage property in MgH_(2)

The practical application of magnesium hydride(MgH_(2))was seriously limited by its high desorption temperature and slow desorp-tion kinetics.In this study,a bullet-like catalyst based on vanadium related MOFs(MOFs-V)was successfully synthesized and doped with MgH_(2) by ball milling to improve its hydrogen storage performance.Microstructure analysis demonstrated that the as-synthesized MOFs was consisted of V_(2)O_(3) with a bullet-like structure.After adding 7wt%MOFs-V,the initial desorption temperature of MgH_(2) was reduced from 340.0 to 190.6℃.Besides,the MgH_(2)+7wt%MOFs-V composite released 6.4wt%H_(2) within 5 min at 300℃.Hydrogen uptake was started at 60℃under 3200 kPa hydrogen pressure for the 7wt%MOFs-V containing sample.The desorption and absorption apparent activity energies of the MgH_(2)+7wt%MOFs-V composite were calculated to be(98.4±2.9)and(30.3±2.1)kJ·mol^(-1),much lower than(157.5±3.3)and(78.2±3.4)kJ·mol^(−1) for the as-prepared MgH_(2).The MgH_(2)+7wt%MOFs-V composite exhibited superior cyclic property.During the 20 cycles isothermal dehydrogenation and hydrogenation experiments,the hydrogen storage capacity stayed almost unchanged.X-ray diffraction(XRD)and X-ray photoelectron spectrometer(XPS)measurements confirmed the presence of metallic vanadium in the MgH_(2)+7wt%MOFs-V composite,which served as catalytic unit to markedly improve the hydrogen storage properties of Mg/MgH_(2) system.

Nanostructuring of Mg-Based Hydrogen Storage Materials:Recent Advances for Promoting Key Applications

With the depletion of fossil fuels and global warming,there is an urgent demand to seek green,low-cost,and high-efficiency energy resources.Hydrogen has been considered as a potential candidate to replace fossil fuels,due to its high gravimetric energy density(142 MJ kg^(-1)),high abundance(H_(2)O),and environmentalfriendliness.However,due to its low volume density,effective and safe hydrogen storage techniques are now becoming the bottleneck for the"hydrogen economy".Under such a circumstance,Mg-based hydrogen storage materials garnered tremendous interests due to their high hydrogen storage capacity(~7.6 wt%for MgH_(2)),low cost,and excellent reversibility.However,the high thermodynamic stability(ΔH=-74.7 kJ mol^(-1)H_(2))and sluggish kinetics result in a relatively high desorption temperature(>300℃),which severely restricts widespread applications of MgH_(2).Nano-structuring has been proven to be an effective strategy that can simultaneously enhance the ab/de-sorption thermodynamic and kinetic properties of MgH_(2),possibly meeting the demand for rapid hydrogen desorption,economic viability,and effective thermal management in practical applications.Herein,the fundamental theories,recent advances,and practical applications of the nanostructured Mg-based hydrogen storage materials are discussed.The synthetic strategies are classified into four categories:free-standing nano-sized Mg/MgH_(2)through electrochemical/vapor-transport/ultrasonic methods,nanostructured Mg-based composites via mechanical milling methods,construction of core-shell nano-structured Mg-based composites by chemical reduction approaches,and multi-dimensional nano-sized Mg-based heterostructure by nanoconfinement strategy.Through applying these strategies,near room temperature ab/de-sorption(<100℃)with considerable high capacity(>6 wt%)has been achieved in nano Mg/MgH_(2)systems.Some perspectives on the future research and development of nanostructured hydrogen storage materials are also provided.

FeCoNiCrMo high entropy alloy nanosheets catalyzed magnesium hydride for solid-state hydrogen storage

The catalytic effect of FeCoNiCrMo high entropy alloy nanosheets on the hydrogen storage performance of magnesium hydride(MgH_(2))was investigated for the first time in this paper.Experimental results demonstrated that 9wt%FeCoNiCrMo doped MgH_(2)started to dehydrogenate at 200℃and discharged up to 5.89wt%hydrogen within 60 min at 325℃.The fully dehydrogenated composite could absorb3.23wt%hydrogen in 50 min at a temperature as low as 100℃.The calculated de/hydrogenation activation energy values decreased by44.21%/55.22%compared with MgH_(2),respectively.Moreover,the composite’s hydrogen capacity dropped only 0.28wt%after 20 cycles,demonstrating remarkable cycling stability.The microstructure analysis verified that the five elements,Fe,Co,Ni,Cr,and Mo,remained stable in the form of high entropy alloy during the cycling process,and synergistically serving as a catalytic union to boost the de/hydrogenation reactions of MgH_(2).Besides,the FeCoNiCrMo nanosheets had close contact with MgH_(2),providing numerous non-homogeneous activation sites and diffusion channels for the rapid transfer of hydrogen,thus obtaining a superior catalytic effect.

Wide temperature range-and damage-tolerant microsupercapacitors from salt-tolerant, anti-freezing and self-healing organohydrogel via dynamic bonds modulation

The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSCs to meet the above requirements.Here,an organohydrogel electrolyte,featured with high salt tolerance,ultralow freezing point,and strong self-healing ability,is experimentally realized via modulating its inner dynamic bonds.Spectroscopic and theoretical analysis reveal that dimethyl sulfoxide has the ability to reconstruct Li^(+)solvation structure,and interact with free water and polyvinyl alcohol chains via forming hydrogen bonds.The organohydrogel electrolyte is employed to build MSCs,which show a boosted energy density,promising wide temperature range-and damage-tolerant ability.These attractive features make the designed organohydrogel electrolyte have great potential to advance MSCs.

Lotus root polysaccharide inhibits the growth of ovarian cancer cells by blocking the cell cycle

Background:Lotus root polysaccharide is a natural antioxidant.As a new anticancer drug,it has anti-proliferation and pro-apoptotic effects in a variety of tumour cells,but its effect on ovarian cancer is not clear.In study,we attempted to elucidate the role and mechanism of lotus root polysaccharide in SKOV3 cells.Methods:In this study,the effect of lotus root polysaccharide on mRNA of SKVO3 cells was analyzed by RNA-seq,and verified by Western blot,flow cytometry,fluorescence detection and other techniques.Results:The results showed that lotus root polysaccharide could inhibit the proliferation of ovarian cancer cells.Then,a change in gene expression was found by RNA-seq.In the mRNA(differentially expressed mRNA)with these differences,significant changes in the cell cycle were found by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis.Subsequently,the proportion of cells in S phase decreases and G2/M phase increases,as seen with propidium iodide staining.Gene Set Enrichment Analysis showed inhibition of the cell cycle,and the gene and protein expression of CDK1,CCNA1 and CCNB1 were inhibited.Conclusion:Our results show that lotus root polysaccharide can inhibit the growth of SKOV3 cells in vitro by blocking the cell cycle at the G2/M phase,which reveals the potential of lotus root polysaccharide in the treatment of ovarian cancer.

Microstructural evolution of Mg-14Gd-0.4Zr alloy during compressive creep

The present work reports the creep behavior and microstructural evolution of the sand-cast Mg-14Gd-0.4Zr alloy(wt.%) prepared by the differential pressure casting machine. Their compressive creep tests at 250 ℃ were performed under various applied stresses(i.e., 60, 80 and100 MPa). Among them, the sand-cast Mg-14Gd-0.4Zr samples examined under 250 ℃/80 MPa for 39 and 95 h, respectively, were chosen to systemically analyze their creep mechanisms using high-angle annular dark field-scanning transmission electron microscopy(HAADF-STEM).The obtained results showed that the enhancement of creep resistance can be mainly attributed to the coherent β' and β'_F phases with an alternate distribution, effectively impeding the basal dislocations movement. However, with the creep time increasing, the fine β'+β'_F precipitate chains coarsened and transformed to semi-coherent β_1 phase and even to large incoherent β phase(surrounded by precipitate-free areas) in grain interiors. The precipitate-free zones(PFZs) at grain boundaries(GBs) were formed, and they could expand during creep deformation. Apart from the main cross-slip of basal and prismatic dislocations, type dislocations were activated and tended to distribute near the GBs. The aforementioned phenomena induced the stress concentrations, consequently leading to the increment of the creep strain.

Risk assessment of heavy metals in soils and vegetables around nonferrous metals mining and smelting sites,Baiyin,China

A field survey was conducted to investigate the metal and arsenic contamination in soils and vegetables on four villages （Shuichuan （SCH）, Beiwan （BWA）, Dongwan （DWA） and Wufe （WFE）） located along, Baiyin, China, and to evaluate the possible health risks to local population through foodchain. Results show that the most significantly contaminated soils occurred upstream at SCH where Cd, Cu and As concentrations exceeded maximum allowable concentrations for Chinese agricultural soil. Further downstream the degree of contamination semi-systematically decreased in concentrations of metal. Generally, the leafy vegetables were more heavily contaminated than non-leafy vegetables. Chinese cabbage is the most severely contaminated, the concentrations of Cd exceeded the maximum permit levels （0.05 mg/kg） by 4.5 times. Bio-accumulate factor also shows that an entry of Cd to food chain plants is the greatest potential. Furthermore, the estimated daily intake amounts of the considered toxic elements （Cd, Pb and Cu） from the vegetables grown at SCH and BWA and DWA have exceeded the recommended dietary allowance levels. Thus, the vegetables grown in three villages above, which affected by Baiyin mining and smelting have a health hazard for human consumption.

Supercritical Antisolvent-based Technology for Preparation of Vitamin D3 Proliposome and Its Characteristics

维生素 D3 (VD3 ) proliposomes (VDP ) ，由 hydrogenated phosphatidycholine (HPC ) 和 VD3 组成了，用 supercritical 反溶剂技术(SAS ) 被准备。在 VDP 装载的 VD3 上的操作条件(温度，压力和部件) 的效果被学习。以 8.0 MPa 的压力的最佳条件， 45 湥 ?慢敳 d 的温度 ??? 晸？？

Metabolic Response of Pakchoi Leaves to Amino Acid Nitrogen

Different nitrogen （N） forms may cause changes in the metabolic profiles of plants. However, few studies have been conducted on the effects of amino acid-N on plant metabolic profiles. The main objective of this study was to identify primary metabolites associated with amino acid-N （Gly, Gln and Ala） through metabolic profile analysis using gas chromatography- mass spectrometry （GC-MS）. Plants of pakchoi （Brassica campestris L. ssp. chinensis L.）, Huawang and Wuyueman cultivars, were grown with different nitrogen forms （i.e., Gly, Gln, Ala, NO3-N, and N starvation） applied under sterile hydroponic conditions. The fresh weight and plant N accumulation of Huawang were greater than those of Wuyueman, which indicates that the former exhibited better N-use efficiency than the latter. The physiological performances of the applied N forms were generally in the order of NO3-N〉Gln〉Gly〉Ala. The metabolic analysis of leaf polar extracts revealed 30 amino acid N-responsive metabolites in the two pakchoi cultivars, mainly consisting of sugars, amino acids, and organic acids. Changes in the carbon metabolism of pakchoi leaves under amino acid treatments occurred via the accumulation of fructose, glucose, xylose, and arabinose. Disruption of amino acid metabolism resulted in accumulation of endogenous Gly in Gly treatment, Pro in Ala treatment, and Asn in three amino acid （Gly, Gln and Ala） treatments. By contrast, the levels of endogenous Gln and Leu decreased. However, this reduction varied among cultivars and amino acid types. Amino acid-N supply also affected the citric acid cycle, namely, the second stage of respiration, where leaves in Gly, Gln and Ala treatments contained low levels of malic, citric and succinic acids compared with leaves in NO3-N treatments. No significant difference in the metabolic responses was observed between the two cultivars which differed in their capability to use N. The response of primary metabolites in pakchoi leaves to amino acid-N supply may serve an important function in pakchoi adaptation to amino acid-N sources.

Nucleation and growth of high purity aluminum grains in directional solidification bulk sample without electromagnetic stirring

A self-made directional solidification device was used to fabricate d 80 mm high purity aluminum ingots. SEM and AFM were used to detect the shape of grain boundaries. The orientation of the grain was studied by X-ray diffractometry. The results show that the nucleation points locate at the intersections of three adjacent grains. The lattice orientation of grains does not alter in the horizontal direction, but gradually approaches the optimum growth direction in the vertical direction during the growth process. All the grains suffer the competition and only the one whose orientation is closest to the preferred direction can occupy the final growth space.

An effective rolling process of magnesium alloys for suppressing edge cracks: Width-limited rolling

To suppress the edge crack of the magnesium alloy sheet during the ordinary rolling process, a new rolling process named width-limited rolling was proposed in this paper. Width-limited rolling is a rolling method in which the width of the alloy sheet is limited by modifying the shape of the rollers, allowing a compressive stress field to form at the edge portion of the alloy sheet during rolling, resulting in the reduction of edge cracks. At present work, magnesium alloy sheets were separately subjected to ordinary rolling and width-limited rolling. The microstructure evolution and mechanical properties of the rolled sheets were investigated by EBSD, TEM, and XRD. The results exhibited that under the same rolling conditions, the sheet after ordinary rolling exhibited obvious edge cracks while no crack was found at the edge of the sheet after width-limited rolling. The edge crack suppressing effect was attributed to the reduction of the tensile stress along rolling direction during WLR, promoting the synchronous extension of the edge and center regions to suppress edge crack tendency. Microstructure observation showed that the compressive twins formed in the sheet after ordinary rolling usually exhibited as thin plates and cannot continue to fully develop due to the premature generation of the edge cracks. However, the compressive twins developed maturely in some of which double twins formed and various slip systems with different dislocation Burgers vectors occurred in the rolled sheet after WLR. More twin intersections and shear bands, providing more potential recrystallization nucleation sites, which are beneficial to weaken basal texture. With the cooperation of twinning and dislocation slip, the texture of the sheet after the width-limited rolling is weakened and the mechanical properties are improved.

INFLUENCE OF SURFACE MORPHOLOGY ON THE MICROHARDNESS OF ELECTROLESS Ni-B DEPOSIT REVEALED BY AFM OBSERVATION

A crystalline and non crystalline two phase Ni B coating was prepared by electroless deposition with potassium borohydride as reducing agent. When the deposit was heated from 10 °C to 500 °C , it took place three kinds of phase transformation and formed corresponding nickel borides. An Atomic Force Microscopy (AFM) was used to directly view the surface morphologies of the samples in various treated states. The AFM images indicate that nano dimensional protrusions grow on the surface of the deposit grain during some heat treatment processes, and they are distinguished greatly from the small bulges existing in the as plated deposit. Further studies show that the microhardness related to the surface topography of the coating to some extent. Especially when a two step heat treatment process was performed, the nano dimensional protrusions on the grain surface grew upt to 40～100 nm in diameter and 10～20 nm in height, and the deposit microhardness reached up to HV1500～1600 in the meantime.

Production of Submicroparticles of β-Sitosterol Using an Aerosol Solvent Extraction System

-sitosterol 的 submicroparticles 被使用一个喷雾器溶剂抽取系统(ASES ) 生产并且由扫描电子显微镜(SEM ) 描绘了， X 光检查衍射(XRD ) ，和 Fourier 转变红外线(英尺红外) 分析。包括流动的压力，温度，答案集中，和比率的运作的参数的效果评价(CO2/solution， r ) 在粒子上，尺寸(PS ) ，产量，和形态学被调查。结果显示出 -sitosterol 的那 microparticles (不到 1000 nm 尺寸并且比 70% 产量大) 能在 10-15 MPa 被获得， 3550 敢漠 ? 桴 ? 牧癡? 牴楡吗？

Magnetic force microscope study on anisotropic NdFeB permanent magnets

NdFeB permanent magnets prepared by powder metallurgy were investigated using magnetic force microscopy (MFM). The excellent MFM images of sample along the surfaces parallel and perpendicular to the alignment axis were collected respectively. The results show the necessity of annealing procedure in the preparation of the samples to remove the polishing surface stress and to illustrate the real magnetic domain structure, so that the much information about both the magnetic structure and the topographic microstructure is obtained. The hard MFM tip is verified to be effective for this material especially for the sample with the examined surface parallel to alignment axis. By analyzing these well-captured magnetic force images, magnetic domains and alignment degree as well as the topographic information such as grain size and the nonmagnetic phases at the grain boundaries were demonstrated.

The First Two-dimensional Supramolecular Network Constructed by Na(Ⅰ) with 2-Methylimidazole-4,5-dicarboxylate Building Blocks

The title complex [Na（H2MIA-）（H2O）]（1,H3MIA = 2-methyl-1H-imidazole-4,5-dicarboxylic acid） has been synthesized by hydrothermal synthesis and structurally characterized by X-ray crystallography.Compound 1 crystallizes in orthorhombic,space group ibam with a = 14.4737（19）,b = 17.553（2）,c = 6.5285（9）,V = 1658.6（4） 3,C6H7N2NaO5,Mr = 210.12,Z = 8,Dc = 1.675 g/cm3,F（000） = 864,μ = 0.188 mm-1,λ（MoKα） = 0.071073 ,R = 0.0383 and wR = 0.0987 for 1046 observed reflections（I 2σ（I））.In the structure of 1,each coordination water coordinates with two Na（I） ions at the same time and links the neighboring Na（I） ions to form a one-dimensional Na（I）-water chain.Each H2MIA-ligand links the neighboring Na（I） of Na（I）-water chain to form a novel two-dimensional supramolecular network.The 2-D network is stabilized by O-H…N hydrogen bonds and π-π interaction.The 2D network is further linked via O-H…O hydrogen bonds to yield a three-dimensional framework.

长期等温时效对镍基高温合金M4706组织和持久蠕变性能的影响（英文）

研究了标准热处理态M4706合金在850°C等温时效过程中微观组织结构的演变及其对合金在870°C/370 MPa条件下持久蠕变性能的影响。试验发现,当时效时间从0 h增加到5000 h时,γ′相的平均尺寸从241 nm增加到484 nm,并且晶界处的碳化物由不连续分布变为连续分布。同时,采用透射电子显微镜对蠕变后的样品进行了观察和分析。试验结果表明,所有热处理态合金的蠕变变形主要是通过基体位错绕过γ′相来实现的。基于这些结果,认为随着时效时间的延长,这些微观组织结构的变化导致了试验合金的持久蠕变强度随时效时间的延长而不断的恶化。