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A core-shell composite consisting of polypyrrole (PPy) nanofibers and TiO 2 was synthesized by using PPy nanofibers as the core and TiO 2 as the shell. The TiO 2 @PPy composite substrate was doped with Pd nanoparticles via chemical reduction. The resulting Pd–TiO 2 @PPy nanocomposite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Brunauer–Emmett–Teller (BET) adsorption analysis before it was utilized to fabricate a hydrogen sensor. Compared with sensors based on TiO 2 @PPy or PPy, the Pd–TiO 2 @PPy sensor was highly sensitive and selective to hydrogen gas, exhibiting a fast response time in air at room temperature. The Pd–TiO 2 @PPy-based sensor exhibited a sensitivity of 8.1% toward 1 vol% of H 2 gas, which is much larger than the sensitivities of sensors based on only TiO 2 @PPy and PPy nanofibers. The excellent reproducibility, stability and selectivity of the Pd–TiO 2 @PPy nanocomposite make it a high potential candidate for hydrogen sensors.

The Phapon gold deposit is located in the northern Laos and the northern segments of the Luang Prabang&ndash, Loei metallogenic belt. The lode-gold orebodies consist of auriferous calcite veins in the middle, and the surrounding siderite alteration and hematite alteration zones in red color. This deposit is hosted in Lower Permian limestone and controlled by a NE-trending ductile&ndash, brittle fault system, and it is characterized by the wallrock alteration of carbonatization and lack of quartz and metal sulfides. The hydrothermal calcite from auriferous calcite veins and red alteration zone, as well as the wall rocks of limestone and sandstone were selected for rare earth elements (REE) and C&ndash, O isotope analyses. The two types of calcite and limestone have generally consistent REE patterns and &delta, Eu and &delta, Ce values, which are completely different from those of sandstone. Calcites from the auriferous vein show slight light rare earth elements (LREE)-depleted patterns and higher Tb/La and Sm/Nd ratios than the ones from the red alteration zone with slight LREE-enriched patterns. These values indicate that the calcites from the auriferous veins and the red alteration zones are products of homologous fluids, but the former ones are generally likely to form later than the latter ones. The hydrothermal calcites have C&ndash, O isotope compositions within the range of marine carbonate, and markedly different from the magmatic or mantle reservoir values. Taking the Y/Ho&ndash, La/Ho and Tb/Ca&ndash, Tb/La variations into consideration, we believe the hydrothermal calcites could be formed from remobilization and recrystallization of the ore-hosted limestone, and the fluid-wallrock interaction played a major role in the gold mineralization in Phapon. In combination with the regional and local geology, the ore-forming process is suspected to be primarily associated with dehydration and decarbonisation of the Lower Permian limestone and Middle&ndash, Upper Triassic sandstones. The Phapon gold deposit could have been formed during the Late Triassic&ndash, Jurassic regional dynamic metamorphism driven by Indochina&ndash, Sibumasu post-collisional magmatism. A number of features in Phapon are similar to epizonal orogenic deposit, but it is still a unique calcite vein type gold deposit in the Luang Prabang-Loei metallogenic belt.

A ternary composite of polypyrrole (PPy), Prussian blue (PB), and graphene oxide (GO), PPy⿿PB⿿GO, was successfully prepared through spontaneous polymerization of pyrrole and formation of PB nanocubes on GO. The obtained nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The results indicate that the PPy-protected PB nanocubes were well dispersed on the GO. Electrochemical testing showed a specific capacitance of 525.4 F g ⿿1 at a current density of 5 A g ⿿1 in the potential range from ⿿0.2 to 0.6 V, obtained in an electrolyte of 1 mol L ⿿1 KNO 3 during the galvanostatic charge⿿discharge cycles, which is superior to the performance of binary cathode materials, including PPy⿿PB and PPy⿿GO nanocomposites. The as-prepared supercapacitor could retain a specific capacitance of 96% after 2000 cycles. It was confirmed that the three components⿿PPy, PB, and GO⿿led to the display of integrated electrochemical behavior and a resulting capacitor with enhanced performance. The significant enhancement in electrochemical performance of the ternary nanocomposite can be attributed to the synergistic effect of PPy-protected PB nanocubes dispersed on GO sheets with the pseudocapacitance from PB and PPy on the double-layer capacitance from GO.

A cobalt–boron/nickel–boron (Co–B/Ni–B) nanocomposite was synthesized in a two-step process by in situ reduction of nickel and cobalt salts. Characterization of the nanocomposite using X-ray diffraction, scanning electron microscopy, and Brunauer–Emmett–Teller adsorption analysis showed that the Co–B nanoparticles were well dispersed on the Ni–B surface. Enlisted as a catalyst in the hydrolysis of ammonia borane (AB) for hydrogen generation (HG), the nanocomposite exhibited better catalytic activity than Co–B and Ni–B at room temperature; the HG rate was 1368.2 mL min−1 g−1 at 25 °C in a 1.5 wt.% AB solution, with a low activation energy of 33.5 kJ mol−1. The effect of the complexing agent (sodium citrate) on the nanocomposite's catalytic activity was also investigated. In addition, recycling tests showed that Co–B/Ni–B was still highly active and preserved 84% of its initial catalytic activity after 11 recover-and-reuse cycles.

BiFeO(3) magnetic nanoparticles (BFO MNPs) are used as a catalyst to develop an ultrasensitive method for the determination of H(2)O(2). It is found that BFO MNPs can catalyze the decomposition of H(2)O(2) to produce OH radicals, which in turn oxidize the weakly fluorescent benzoic acid to a strongly fluorescent hydroxylated product with a maximum emission at 405nm. This makes it possible to sensitively quantify traces of H(2)O(2). Under optimized conditions, the fluorescence intensity is observed to be well linearly correlated with H(2)O(2) concentration from 2.0x10(-8) to 2.0x10(-5)molL(-1) with a detection limit of 4.5x10(-9)molL(-1) (S/N=3). In addition, a selective method for glucose determination is developed by using both glucose oxidase and BFO MNPs, which has a linear range for glucose concentration from 1.0x10(-6) to 1.0x10(-4)molL(-1) with a detection limit of 5.0x10(-7)molL(-1). These new methods have been successfully applied for the determination of H(2)O(2) in rainwater and glucose in human serum samples.

The inner molecular polarizability index (IMPI) was developed based on the polarizability effect index (PEI). Three parameters were calculated: NC(eff), the quasi-length of carbon chain; ΔPEIOH, the difference of polarizability effect index (PEI) of alkyl substituents in alcohols; and POH, the proportion of oxygen atom in the OH group to the total number of carbon and oxygen atoms in the alcohol. The multiple regression analysis (MRA) correlating boiling point with the three parameters was carried out for 211 alkanes and 117 alcohols. Excellent results were obtained with the correlation coefficient r = 0.9990 and standard deviation s = 6.02 °C.

Lignin isolated from enzymatic hydrolyzed cornstalks (EHL) is a renewable natural polymer, and rubber is one of the most important polymer materials. The application of EHL in rubber industry is of great significance. The influence of EHL and antioxidant RD on the vulcanizing characteristics, thermal oxidative aging stability under free condition, and water extraction resistance of styrene‐butadiene rubber (SBR) were investigated. The effect of EHL/antioxidant D composite antioxidant on the thermal oxidative ageing of SBR was also evaluated. Results showed that the protection of SBR from thermal oxidative aging by EHL/antioxidant D composite antioxidant was superior to that of antioxidant D. This is because EHL molecules have hindered phenol group and have excellent auxiliary antioxidant role with antioxidant D. Moreover, the influence of EHL on the vulcanizing characteristics of SBR compounds was better than that of antioxidant RD, and EHL can reduce the cure rate and increase the optimum cure time. It is because that the EHL molecules have hindered phenol group and methoxy group, which can form a special structure to capture free radical and terminate the chain reaction. The retained tensile strength of SBR compounds with EHL was similar to that of the samples with antioxidant RD, while the retained elongation at break of SBR compounds with EHL was higher than that of the samples with antioxidant RD. In addition, the SBR compounds with EHL have a good water extraction resistance property, which was similar to the samples with antioxidant RD. This is because EHL have large molecular weight, good stability and low solubility in water. In conclusion, due to the low price, abundant resources, non‐toxic and pollution‐free, etc., EHL will have broad application prospect.