Ba6RE2Ti4O17 (RE= Nd, Sm,Gd, Dy-Yb): A family of quasi-two-dimensional triangular lattice magnets

Rare-earth-based triangular-lattice magnets provide the fertile ground to explore the exotic quantum magnetic state. Herein, we report a new family of RE-based triangular-lattice magnets Ba6RE2Ti4O17(RE= rare earth ions) crystallized into the hexagonal structure with space group of P63 mmc, where magnetic rare earth ions form an ideal triangular lattice within the ab-plane and stack in an AA -type fashion along the c-axis. The low-temperature magnetic susceptibility results reveal all the serial compounds have the dominant antiferromagnetic interactions and an absence of magnetic ordering down to 1.8 K. The magnetization and electron spin resonance results indicate distinct magnetic anisotropy for the compounds with different RE ions. Moreover, Ba6Nd2Ti4O17 single crystal is successfully grown and it exhibits strong Ising like anisotropy with magnetic easy-axis perpendicular to the triangle-lattice plane, being a candidate to explore quantum spin liquid state with dominant Ising-type interaction.Comment: 18 pages, 8 figure

Identification of Urban Functional Area by Using Multisource Geographic Data: A Case Study of Zhengzhou, China

The rational allocation of functional areas is the foundation for addressing the sustainable development of cities. Efficient and accurate identification methods of urban functional areas are of great significance to the adjustment and testing of urban planning and industrial layout optimization. Firstly, by employing multisource geographic data, an identification method of urban functional areas was developed. A quantitative measurement approach of the urban functional area was then established considering the comprehensive effects of human-land, space-time, and thematic information to present the covering area of ground objects, public awareness, and empirical research. Finally, the Zhengzhou city, which locates in Henan province of central China, was used to test the method. The results show that the developed method is efficient, accurate, and universal and can identify urban functional areas quickly and accurately. We found that the overall distribution of Zhengzhou’s functional areas presents a spatial pattern of single and multimixed coordinated development. The city’s commercial functional areas and commercial-based mixed functional areas are located in the city’s central area. The green square’s function area occupies relatively low and is mainly distributed in the city’s fringe

Influence of PTFE and Nafion on the UtilizationEfficiency of Pt/C Catalyst in PEMFC

本文利用循环伏安法，结合透射电镜和扫描电镜研究了质子膜燃料电池催化层中加入的聚四氟乙烯（ＰＴＦＥ）和全氟磺酸树脂（Ｎａｆｉｏｎ）对催化剂利用率的影响．ＰＴＦＥ对催化剂利用率的影响很小．但在亲水型电极中，催化剂颗粒之间的电子导通会受到Ｎａｆｉｏｎ的阻碍，并导致催化剂利用率降低．由于Ｎａｆｉｏｎ分子很小，因此与Ｐｔ／Ｃ中Ｐｔ颗粒的接触没有大问题With cycling voltammetry curve(C-V), TEM and SEM photographs, the influence of PTFE and Nafion on the platinum utilization in catalyst layer of PEMFC was investigated. The results show that in gas diffusion electrode, the blocking effect of PTFE in the platinum utilization is not pronunced. In the thin_film catalyst layer, the electron conduct of the catalyst was blocked by the nafion solid and this caused the decrease of platinum utilization. With the increase of the nafion content in the catalyst layer, both platinum utilization and the electron conductivity decreased in the catalyst layer. Because the molecule size of nafion is smaller than that of Pt particles, there should no big problem for the contact between nafion and Pt particles.作者联系地址：中科院大连化学物理研究所Author's Address: Dalian Inst. of Chem. Phys., Chinese Acad. of Sci., Dalian11602

<i>Rehmannia glutinosa</i> Polysaccharides: Optimization of the Decolorization Process and Antioxidant and Anti-Inflammatory Effects in LPS-Stimulated Porcine Intestinal Epithelial Cells

Polysaccharide decolorization has a major effect on polysaccharide function. In the present study, the decolorization of Rehmannia glutinosa polysaccharides (RGP) is optimized using two methods—the AB-8 macroporous resin (RGP-1) method and the H2O2 (RGP-2) method. The optimal decolorization parameters for the AB-8 macroporous resin method were as follows: temperature, 50 °C; macroporous resin addition, 8.4%; decolorization duration, 64 min; and pH, 5. Under these conditions, the overall score was 65.29 ± 3.4%. The optimal decolorization conditions for the H2O2 method were as follows: temperature, 51 °C; H2O2 addition, 9.5%; decolorization duration, 2 h; and pH, 8.6. Under these conditions, the overall score was 79.29 ± 4.8%. Two pure polysaccharides (RGP-1-A and RGP-2-A) were isolated from RGP-1 and RGP-2. Subsequently, their antioxidant and anti-inflammatory effects and mechanisms were evaluated. RGP treatment activated the Nrf2/Keap1 pathway and significantly increased the activity of antioxidant enzymes (p p < 0.05). RGP-1-A had a significantly better protective effect than RGP-2-A, likely owing to the sulfate and uronic groups it contains. Together, the findings indicate that RGP can act as a natural agent for the prevention of oxidation and inflammation-related diseases

Determinative Surface-Wrinkling Microstructures on Polypyrrole Films by Laser Writing

We report a simple and efficient laser-writing strategy to fabricate hierarchical nested wrinkling microstructures on conductive polypyrrole (PPy) films, which enables us to develop advanced functional surfaces with diverse applications. The present strategy adopts the photothermal effect of PPy films to mimick the formation of hierarchical nested wrinkles observed in nature and design controlled microscale wrinkling patterns. Here, the PPy film is grown on a poly­(dimethylsiloxane) (PDMS) substrate via oxidation polymerization of pyrrole in an acidic solution, accompanied by in situ self-wrinkling with wavelengths of two different scales (i.e., λ₁ and λ₂). Subsequent laser exposure of the PPy/PDMS bilayer induces a new surface wrinkling with a larger wavelength (i.e., λ₃). Owing to the retention of the initial λ₁ wrinkles, we obtain hierarchical nested wrinkles with the smaller λ₁ wrinkles nested in the larger λ₃ ones. Importantly, we realize the large-scale path-determinative fabrication of complex oriented wrinkling microstructures by controlling the relative motion between the bilayer and the laser. Combined with the induced changes in surface color, surface-wrinkling microstructures, and conductivity in the PPy films, the laser-writing strategy can find broad applications, for example, in modulation of surface wetting properties and fabrication of microcircuits, as demonstrated in this work