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The observation facts of trend and variability are estimated for a century‐long timescale, as well as some possible attributions affecting temperature extremes over Beijing‐Tianjin‐Hebei region. In this paper, the new constructed daily maximum and minimum temperature series during the last 100 years in situ stations of Beijing, Tianjin and Baoding city are used, and two 30‐year baseline climatology of 1961–1990 and 1980–2010 are both used in calculating extreme temperature events. The results indicate that there are long‐lasting, frequent and serious extreme warming over Beijing‐Tianjin‐Hebei region, especially for extreme low temperature, with larger declining trends (at 5% significance) from 1981 to 2010 baseline than those from 1961 to 1990 baseline. And from a statistical perspective, El Niño decay years and surface sea temperature (SST) anomalies at some typical ocean regions of the Arabian Sea and the Bengal Bay on the northern Indian Ocean, the Western Pacific and the Mid Atlantic, Southern Indian Ocean and around 45°–85°E, 68°–82°N on the southwest Arctic Ocean can be used as the warning signals denoting extreme warming over Beijing‐Tianjin‐Hebei region. Additionally, urbanization has a significant (at 5% significance) effect on extreme warming over Beijing‐Tianjin‐Hebei region since 1979, with 24.3% warming contribution for annual minimum temperature. [ABSTRACT FROM AUTHOR]

Summary: Poly(ethylene oxide) (PEO) polymer electrolyte has been regarded as a potential solid electrolyte which can be applied in all‐solid‐state lithium‐ion batteries (ASSLIBs). Nevertheless, low electrochemical properties and poor electrolyte/Li anode interfacial stability hinder its further application. In our work, the Li1.3Al0.3Ti1.7(PO4)3 (LATP) nanomaterials with Nasicon structure have been synthesized using a simple solvent‐thermal method, followed by being embedded into PEO polymer to form LATP filled PEO solid composite electrolytes. Effects of LATP content and particle size on electrochemical performances of solid electrolytes have been studied. By adjusting the calcination temperature, the uniformly distributed Nasicon‐type LATP powders with different sizes can be obtained. The electrochemical properties of PEO polymer electrolyte have been effectively enhanced by filling LATP nanoparticles. The composite electrolyte filled with 5 wt% LATP particles calcined at 850°C exhibits a high ionic conductivity of 5.24×10−4 S cm−1 at 55°C, which has a high electrochemical stability window of over 5 V versus Li/Li+ and a superior interfacial stability with Li metal. A LiFePO4/Li ASSLIB fabricated with the optimum composite electrolyte shows the excellent rate capability, and its discharge capacities at 0.2C, 0.5C, 1C, and 2C are 151.97, 151.56, 145.51, and 128.02 mAh·g−1. Moreover, the discharge capacity of the cell decreases from 151.69 to 130.53 mAh·g−1 after 100 charge‐discharge cycles at 0.5C rate, and the corresponding capacity retention is 86.05%. These results demonstrate that LATP nanoparticles obtained via the solvent‐thermal method are the alternative fillers for PEO polymer electrolyte. [ABSTRACT FROM AUTHOR]

A magnesium (Mg)-rich primer can provide cathodic protection for an aluminum (Al) alloy due to the lower potential of Mg. However, the Mg-rich primer prepared by simple blends shows poor flexibility and impact resistance. In this paper, bisphenol-A type epoxy resin E-20 was graft modified by hydroxyl silicon oil (HS), amino silane coupling agent and diphenyl-methane-diisocyanate (MDI) by three different ways. Then Mg-rich primer was prepared by direct blends of modified resins. Results indicate that the introduction of siloxane groups could improve the comprehensive performance of the coating especially the flexibility and impact resistance. Furthermore, Mg-rich primer prepared from MDI modified epoxy resin even possesses excellent salt spray and aging resistance. [ABSTRACT FROM AUTHOR]

Hydroxyl-containing fluoroacrylate copolymers with different fluorine and hydroxyl concentrations were synthesized via free-radical solution polymerization. Transparent fluorinated polyurethane (FPU) films were prepared by curing the copolymers with HDI (hexamethylene diisocyanate) trimer. The Fourier transform infrared spectroscopy (FT-IR) results revealed introduction of fluorine both into the copolymer and polyurethane. X-ray photoelectron spectroscopy (XPS) analyses indicated that a gradient concentration of fluorine existed in the depth profile of the fluorinated polyurethane films. The highest contact angle (CA) was obtained for the FPU film with fluoroacrylate monomer concentration of 22 wt.% because of fluorine present on the film surface. The surface topographies detected by SEM and AFM indicated that surface roughness contributed little to the film hydrophobicity. By increasing the fluoroacrylate monomer concentration, the decreasing of crosslinking degree of hard segment resulted in lowering the first degradation temperature, while more C-F groups in soft segment led to higher second degradation temperature. UV-Vis spectrophotometer measurements indicated that the FPU film with the fluoroacrylate monomer concentration of 16 wt.% still had a high transmittance of more than 90 % in the whole visible wavelength range. [ABSTRACT FROM AUTHOR]

It is well documented that the East Asian summer monsoon has been experiencing a steady weakening trend in recent decades. Because the Asian summer monsoon (including both East Asian monsoon and South Asian monsoon) is the largest and most pronounced monsoonal system in the world, its change in strength may exert a profound impact on global weather and climate systems, especially on the rainfall pattern in South and East Asia. On the other hand, as a vast elevated landmass, the Tibetan Plateau forms a huge heat source protruding into the free atmosphere. Setting against the backdrop of global climate change, whether or not does the change of this heating affect the change of Asian summer monsoon and thus rainfall distribution? Here we show that the apparent heat source over the Tibetan Plateau is closely correlated with the East Asian summer monsoonal circulation, and that the weakening of the East Asian summer monsoon is closely associated with the decreasing trend of the Tibetan Plateau apparent heat source. Further analysis indicates that the change of rainfall pattern in China in recent decades is consistent with the decreasing of the East Asian summer monsoon. [ABSTRACT FROM AUTHOR]

The dependence of particulate Langmuir-Blodgett (LB) monolayer quality on the surface nature of the substrate was investigated by pretreating the substrates with different methods, and the optimal withdrawal speed was determined by detecting the quality of particulate monolayers deposited at different withdrawal speeds. Furthermore, the effects of stearic acid (SA) concentration on the quality of particulate monolayers were discussed. Results indicated that surface amination would favor the transfer of the floating particulate monolayer from the interface to the substrate, which would be attributed to the formation of chemical bonds between the -2 groups on the substrate surface and the functional groups of - and - groups on surfaces of particles floating at the interface. And the withdrawal speed of 1 mm ⋅ min-1 was appropriate for the fabrication of high-quality particulate LB monolayer because low withdrawal speed can offer sufficient time to form chemical bonds and expel the subphase from the substrate. Additionally, SEM images illustrated that the SA concentration of 0.40 mg ⋅ mL-1 was suitable for the fabrication of well-ordered particulate LB monolayers composed by the particles of 380 nm. [ABSTRACT FROM AUTHOR]