Simultaneous water recovery and hydrogen production by bifunctional electrocatalyst of nitrogen-doped carbon nanotubes protected cobalt nanoparticles

Cobalt nanoparticles encapsulated in nitrogen-doped carbon nanotubes (Co@NC) are obtained by a simple pyrolysis of Co-MOF (ZIF-67) for the bifunctional water recovery and hydrogen production. The results showed that calcination temperature of ZIF-67 significantly affected the morphology and catalytic performance. Wastewater are effectively recovered in the presence of the Co@NC and oxidant, which is promoted by anodic oxidation reactions. Co@NC as the cathode catalyst exhibited excellent hydrogen evolution reaction catalytic activity with a low onset potential of ?51 mV (vs. RHE, current density of 0.5 mA/cm²), Tafel slope of 96.73 mV/dec and extraordinary long-term durability. Finally, as a proof of concept, a home-made two-electrode device employed Co@NC as both anode and cathode catalyst for continuous water recovery and simultaneous hydrogen production, which possesses the possibly applications in solving the environmental pollution and energy crisis.     

脉冲离子阱的设计

本文提出了一种适用于飞行时间质谱仪的新颖离子阱。它可在脉冲状态下工作，并可存储极宽质量范围的离子。离子的存储量与离子阱中心所加的负电位理论上成正比，并可选择被存储离子的能量范围，可做为能量过滤器，减小离子的能量分散对分辨本领的影响；特别是该离子阱具有独立于离子源而引入离子的特点，扩大了应用范围。与通常所用的三维四极离子阱相比，其机械加工和配套电子线路都比较简单，可在一般的实验室内制做。     

Determination of the geographical origin of wine using joint analysis of elemental and isotopic composition. II—Differentiation of the principal production zones in france for the 1990 vintage

Stable isotope analysis of grape juices and fermented products involving 2H-NMR spectroscopy and isotope ratio mass spectroscopy was carried out in combination with elemental determinations performed by atomic absorption spectroscopy using flame and thermal ionisation. One hundred and sixty five grape samples were carefully collected in well-defined vineyards of France situated in Alsace, Burgundy, Beaujolais and the Loire Valley. Moreover, the samples from Burgundy were picked from four typical Appellations (Cǒtes de Nuits, Cǒtes de Beaune, Cǒtes Chalonnaises and Mǎconnais) in order to ‘zoom’ the approach to smaller production areas. An exhaustive statistical evaluation of the 165 ± 16 data set was carried out by analysis of variance and principal component analysis. To conclude this study, the classification of the samples in typical Appellations was carried out by discriminant analysis with a nearly 100% degree of achievement.     

基于游标效应的高灵敏光纤温度和应变传感器

提出一种基于光纤Sagnac干涉仪(FSI)和偏振模干涉仪(PMI)级联结构的高灵敏光纤温度和应变传感器。FSI作为参考干涉仪,是将对温度、应变、弯曲及扭转不敏感的椭圆芯保偏光纤(ECPMF)引入到Sagnac环内制得的。PMI作为传感干涉仪,是对光纤起偏器与末端端面镀金的熊猫型保偏光纤(PMF)的快轴/慢轴以45°角进行熔接制得的。参考干涉仪的自由光谱区(FSR)易被调整为接近传感干涉仪的FSR,从而产生光学游标效应,实现灵敏度放大。实验结果表明:所设计的级联传感器的温度灵敏度达15.56 nm/℃,是单个PMI的11.12倍;应变灵敏度达154.04 pm/με,是单个PMI的11.81倍。所设计的传感器具有灵敏度高、制作简单、稳定性好等优点,在航空航天、工业生产等领域中具有广阔的应用前景。     

Differences in brain networks of children with ADHD: Whole-brain analysis of resting-state fMRI

The aim of this study was to investigate changes of functional connectivity (FC) in resting state networks (RSNs) in medication-naive children with attention-deficit/hyperactivity disorder (ADHD). Twenty children with a diagnosis of ADHD (11.8 ± 2.29 years; 16 boys) and 20 age-matched typically developing (TD) children (13 ± 1.78 years; 10 boys) were included. It was found that brain FC differences in children with ADHD are not only in the well known RSNs such as default mode, visual, sensory motor, attentional, frontal, central executive, and frontal networks but also involve interaction among whole brain functional networks. In addition, basal ganglia and cerebellum networks which later gained importance were examined in this study. All RSNs has been shown significant differences in special regions which belongs related RSN. The highest positive (HPC) and negative (HNC) correlation were calculated between 14 independent components including 11 different RSNs. We observed different FC changes (decreased/increased) according to the RSNs between ADHD and control children. The HPC was defined between the visual and cerebellum network in ADHD children and between the dorsal attentional network and sensory motor network in TD children. Also, the HNC was detected between the visual and basal ganglia network in both groups. Investigating intra and inter network FC could provide a framework to better understand the neural basis that underlies core symptom dimensions in ADHD.