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The control design of inductive power transfer (IPT) systems has attracted a lot of attention in the field of wireless power transmission. Due to the high-order resonant networks and multiple loads in IPT systems, a simplified model of an IPT system is preferred for analysis and control design, and a controller with strong robustness is required. Hence, an active disturbance rejection control (ADRC) for IPT systems is proposed in this paper. To realize the employment of ADRC, firstly a small-signal model of an LC series-compensative IPT system is derived based on generalized state-space averaging (GSSA), then the ADRC is implemented in the designed IPT system. The ADRC not only provides superior robustness to unknown internal and external disturbances, but also requires few knowledge of the IPT system. Due to the convenient realization of ADRC, the designed IPT system retains its simple structure without any additional circuits. Finally, a frequency domain analysis and experimental results have validated the effectiveness of the employed ADRC, especially its robustness in the presence of frequency drifts and other common disturbances. [ABSTRACT FROM AUTHOR]

A series of carbon black-supported bimetallic Ru-Co nanoparticles catalyst were synthesized via the chemical reduction of corresponding metal precursor in ethylene glycol, for H2 generation from NaBH4 methanolysis. The composition, morphology and structure of the novel nanomaterial were well characterized by XRD, XPS, HRTEM, EDX and SEM, showing the good dispersion of supported Ru-Co nanoparticles with an average diameter of 2.4 nm. Significantly, the highest H2 generation rate is observed in the case of Ru-Co/C catalyst with Ru/ Co ratio of 5, achieving 9.36 L min-1 g-1 at 25 °C, which is comparable to the reported pure Ru catalysts. Furthermore, the recycle test confirms our catalyst can be practically applied. Our work highlights the synergetic effect in bimetallic catalytic system for boosting H2 generation rates from NaBH4 methanolysis. [ABSTRACT FROM AUTHOR]

Acid-base bifunctional organic polymeric catalysts were synthesized with tunable structures. we demonstrated two synthesis approaches for structural fine-tune. In the first case, the framework flexibility was tuned by changing the ratio of rigid blocks to flexible blocks within the polymer framework. In the second case, we precisely adjusted the acid-base distance by distributing basic monomers to be adjacent to acidic monomers, and by changing the chain length of acidic monomers. In a standard test reaction for the aldol condensation of 4-nitrobenzaldehyde with acetone, the catalysts showed good reusability upon recycling and maintained relatively high conversion percentage. [ABSTRACT FROM AUTHOR]

Gram-negative, non-motile, short rod-shaped or spherical bacterial strain that accumulates poly-β-hydroxybutyrate (PHB) granules was isolated from the Beibu Gulf in the South China Sea. Cells have no polar or subpolar flagella, dividing by binary fission. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus Paracoccus, family Rhodobacteraceae, order Rhodobacterales, class Alphaproteobacteria. The closest neighbours were Paracoccus aestuarii strain B7 (97.2% similarity), Paracoccus zeaxanthinifaciens ATCC 21588 (97.1% similarity) and Paracoccus homiensis DD-R11 (96.8%). The predominant fatty acids were C ω7c (82.1%), and significant amounts of C (5.6%), C 3-OH (2.3%) and C (1.5%) were present. The predominant respiratory ubiquinone of strain JLT1284 was Q-10 and the DNA G+C content of strain JLT1284 was 67.0 mol%. The isolate was also distinguishable from members of the genus Paracoccus on the basis of phenotypic and biochemical characteristics. It is evident from the genotypic, chemotaxonomic and phenotypic data, therefore, that strain JLT1284 represents a novel species of the genus Paracoccus, for which the name Paracoccus beibuensis sp. nov. is proposed. The type strain is JLT1284 (=LMG 24871 = CGMCC 1.7295). [ABSTRACT FROM AUTHOR]

A series of fluorinated nanosized HZSM-5 catalysts were prepared by impregnating the zeolite with NH4F solution. The samples were characterized by XRD, XRF, FTIR-Py, TPD, 27Al and 29Si MAS-NMR. The effect of calcination temperature on the structure and acidity was studied in the range of 400–500 °C. When the calcination temperature increases, more framework aluminum atoms are removed due to the fluorination. As a result, the number of acid sites and the acid strength decrease, but the ratio of the total Brönsted acid sites to the total Lewis acid sites (BT/LT) increases. The fluorinated nanosized HZSM-5 catalysts exhibit better stability in the methylation of biphenyl (BP) with methanol. Moreover, the stability increases with the increase of the calcination temperature. When the fluorinated nanosized HZSM-5 is calcined at 500 °C, the conversion of BP can keep at about 10% for 50 h. The enhancement of stability may be due to the decrease of the acid strength and the increase of the ratio of BT/LT. [ABSTRACT FROM AUTHOR]

The first high-performance electroactive benzoxazine with an aniline dimer in its structure has been synthesized from 4-aminodiphenylamine (aniline dimer), paraformaldehyde, and phenol. FT-IR and 1H NMR are used to characterize the molecular structure of the electroactive benzoxazine monomer (PH-BA). The reversible one-electron transfer between the neutral form and the radical-cation form takes place in the redox reaction of PH-BA and its corresponding polymer (pPH-BA). The pPH-BA exhibits oxidation and reduction currents of 0.122 and 0.128 mA cm-2, respectively, which are higher than the published benzoxazine/ aniline oliogomer blend. The current value of the redox peaks of pPH-BA doubles when compared with PH-BA, which might be attributed to the formation of the electron-donating hydroxyl groups during the thermally induced ring-opening polymerization and the hydrogen bonding interactions between phenolic-OH groups and aniline units in pPH-BA network. The pPH-BA coating exhibits outstanding corrosion resistance properties with a corrosion rate of 0.0091 mm per year for carbon steel Q235, which is significantly lower than that of non-electroactive polybenzoxazines. pPH-BA can further facilitate the formation of a metal oxide layer composed of Fe2O3 on the steel surface and was characterized by SEM, Raman, and XPS. [ABSTRACT FROM AUTHOR]

Pure and mixed lanthanum and cerium oxides were synthesized via a reverse microemulsion-templated route. This approach yields highly homogeneous and phase-stable mixed oxides with high surface areas across the entire range of La:Ce ratios from pure lanthana to pure ceria. Surprisingly, all mixed oxides show the fluorite crystal structure of ceria, even for lanthanum contents as high as 90%. Varying the La:Ce ratio not only allows tailoring of the oxide morphology (lattice parameter, pore structure, particle size, and surface area), but also results in a fine-tuning of the reducibility of the oxide which can be explained by the creation of oxygen vacancies in the ceria lattice upon La addition. Such finely controlled syntheses, which enable the formation of stable, homogeneous mixed oxides across the entire composition range, open the path towards functional tailoring of oxide materials, such as rational catalyst design via fine-tuning of redox activity. [ABSTRACT FROM AUTHOR]

Long-period stacking ordered (LPSO) phases play an essential role in the development of magnesium alloys because they have a direct effect on mechanical and corrosion properties of the alloys. The LPSO structures are mostly divided to 18R and 14H. However, to date there are no consistent opinions about their degradation properties although both of them can improve mechanical properties. Herein we have successfully obtained two LPSO phases separately in the same Mg-Dy-Zn system and comparatively investigated the effect of different LPSO phases on degradation behavior in 0.9 wt.% NaCl solution. Our results demonstrate that a fine metastable 14H-LPSO phase in grain interior is more effective to improve corrosion resistance due to the presence of a homogeneous oxidation film and rapid film remediation ability. The outstanding corrosion resistant Mg-Dy-Zn based alloys with a metastable 14H-LPSO phase, coupled with low toxicity of alloying elements, are highly desirable in the design of novel Mg-based biomaterials, opening up a new avenue in the area of bio-Mg. [ABSTRACT FROM AUTHOR]

Hydrophilic Ti-MCM-41 was modified by alkylsilyl groups using n-octadecyltrichlorosilane as the precursor, yielding an amphiphilic molecular sieve denoted as OTS-Ti-MCM-41. The sample retained mesoporous structure and morphology, as confirmed by XRD, N2 adsorption–desorption, and SEM. The presence of surface alkylsilyl groups was confirmed by infrared spectroscopy. The amphiphilic OTS-Ti-MCM-41 located at the boundary between aqueous and organic phases acted as a phase-boundary catalyst for the photooxidation of dibenzothiophene (DBT) without the need of adding a co-solvent to drive liquid–liquid phase transfer. With H2O2 as the oxidant, the conversion of DBT on OTS-Ti-MCM-41 was up to 98% at 2 h, much higher than that on Ti-MCM-41. When air was used instead of H2O2 as the oxidant, the conversion of DBT on OTS-Ti-MCM-41 was up to 85% at 2 h. Hydrophilic Ti-MCM-41 was modified by alkylsil groups using n-octadecyltrichlorosilane as the precursor. The resulting OTS-Ti-MCM-41 sample located at the boundary between aqueous and organic phases acted as a phase-boundary catalyst for the photooxidation of dibenzothiophene (DBT).[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]