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A composite of Fe3O4 nanoparticles anchored on a carbon support (Fe3O4/C), possessing both superparamagnetism and molecular oxygen activating properties, was prepared by an ammonia-assisted precipitation method. Fe3O4/C could catalyze the selective oxidation of various benzyl alcohols with air as the oxidant source, and could be easily separated and recycled with an external magnet. The small particle size and the interaction between the Fe3O4 nanoparticles and carbon support endow the Fe3O4/C catalyst with relatively high reducibility. Its oxidation state is easy to change. This intrinsic property of the Fe3O4 nanoparticles could be responsible for the high activity of Fe3O4/C in the aerobic oxidation of alcohols. [ABSTRACT FROM AUTHOR]

In this work, strong electrochemiluminescence (ECL) emission was achieved by using one type of the G-quadruplex selective iridium (III) complex as an efficient ECL signal probe. Based on the typical sandwich immunoreaction between the cardiac troponin-I antigen (cTnI) and its corresponding antibody, iridium (III) complex was introduced according to its specific interaction with G-quadruplex DNA that modified on the surface of negatively charged gold nanoparticles ((−)AuNPs), inducing an increased ECL signal, which was proportional to cTnI concentration. Based on of this, quantitative detection of cTnI could be realized in the range of 5.0 fg/mL-100 ng/mL, with a detection limit of 1.67 fg/mL. Moreover, the proposed immunosensor was successfully applied for the diagnosis of cTnI in human serums from healthy individuals and acute myocardial infarction (AMI) patients, suggesting a great potential application value in the early diagnosis of AMI. In the present work, a sensitive ECL immunosensor was constructed for the detection of trace cTnI in AMI patients by using the G-quadruplex selective iridium (III) complex as an efficient signal probe. [Display omitted] • The G-quadruplex selective iridium (III) complex firstly used as an efficient ECL signal probe. • The utilization of G-quadruplex selective iridium (III) complex enhanced the specificity of the method for cTnI detection. • Sensitive detection of cTnI was realized with a detection limit of 1.67 fg/mL. • The assay can further used to detect cTnI in normal and AMI patient serum samples. [ABSTRACT FROM AUTHOR]

The work reported was aimed at a simple method to improve the of Mo/HMCM-22 in methane . The catalysts were characterized using X-ray diffraction, scanning , N2 adsorption-desorption, NH3 temperature-programmed desorption, infrared spectra of pyridine adsorption, and thermogravimetric analysis. Physicochemical measurements indicated that Mo species with smaller size in HMCM-22 would sublimate more easily and form Mo species at the atomic/molecular level and then interact well with the internal Brønsted acid sites to form Mo-O-Al active species. Catalytic results confirmed that nano-MoO3-modified HMCM-22 showed higher methane conversion and aromatics yield (13.1 versus 8.9%) than commercial MoO3-modified HMCM-22 (11.0 versus 7.5%). In addition, nano-MoO3-modified HMCM-22 showed better durability compared with commercial MoO3-modified MCM-22. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A silica-supported CdS nanoparticle photocatalyst exhibits excellent visible-light driven H2 evolution activity without the use of a cocatalyst. The apparent quantum yield can reach 42% under 420 nm light illumination. [ABSTRACT FROM AUTHOR]

Core-shell structural magnetic nanocatalysts, involving carbon-coated magnetic Fe3O4 nanoparticles supported on graphene oxide sheets (mildly reduced graphene oxide (MRGO)/Fe3O4@C) and carbonaceous coatings on magnetic Fe3O4 nanoparticles (Fe3O4@C), for immobilizing metal (CuII, CoII, FeIII or VOIV)-salen complexes were prepared by a facile, green, and efficient chemical approach and first applied in the aerobic epoxidation of styrene with air as the oxidizing agent. The prepared catalysts were characterized by different techniques, such as XRD, TEM, FTIR spectroscopy, inductively coupled plasma atomic emission spectroscopy, TEM, thermogravimetric analysis, Raman spectroscopy, and X-ray photoelectron spectroscopy. The magnetic nanocatalysts MRGO/Fe3O4@C-salen-M (M=Cu, Co, Fe, or V) exhibited higher catalytic reactivity than that of the corresponding Fe3O4@C-salen-M (M=Cu, Co, Fe, or V) species possibly owing to site isolation, good dispersion of magnetic Fe3O4 nanoparticles, and an efficiently synergistic effect between the metal complexes and the supports. Furthermore, MRGO/Fe3O4@C-salen-Co exhibited up to 92.3 % conversion of styrene and 59.2 % selectivity to the styrene oxide upon using air as the oxidizing agent and showed good recoverability with negligible loss in activity and selectivity within successive runs owing to superparamagnetism. Most importantly, these materials can be easily recovered by simple magnetic separation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Graphite oxides with different microstructure were prepared via thermal treatment. [•] The structure changes from multilayer sheets to an ultrathin 2D structure. [•] The amount of oxygen-containing groups decreases upon temperature increasing. [•] Surface carboxylic groups act as active sites for the oxidation of benzyl alcohol. [Copyright &y& Elsevier]

Highlights: [•] A series of imprinted catalysts were successfully synthesized. through a metal-template/metal-exchange method. [•] Characterized by XRD, FT-IR, UV–visible, ICP-AES, TEM, TG, Raman, BET and XPS. [•] The imprinted catalysts were active and showed good recoverability. [Copyright &y& Elsevier]

Abstract: Non-crystalline surface-modified hollow nanospheres of silica (HNS) with different amine groups were synthesized by the co-condensation under neutral conditions. The obtained materials were characterized by N2 adsorption–desorption isotherms, Fourier-transform infrared spectroscopy (FTIR), transmission electron micrographs (TEM), scanning electron micrographs (SEM), back titration, elemental analysis and thermogravimetric analysis (TGA). The effect of organoamine type, amine density, and the presence of silanol groups on the catalytic activity was investigated. The capping of silanols with trimethylsilyl groups resulted in a reduction in catalytic activity, indicating the existence of cooperative effect between amine and silanol in the condensation reaction. [Copyright &y& Elsevier]

As an indispensable transport equipment installed on the ship, marine tower cranes play pivotal roles to accomplish heavy offshore operations such as cargo transfer, undersea salvage, maritime rescue tasks and so on. Most of the existing researches only consider the control problem under the effect of single-pendulum angle, however, there has double-pendulum phenomenon in the case of practical offshore operations caused by the connection structure between the hook and the payload. Besides, the dead zone constraint of the motor drivers should be fully considered in high performance controller design process. Therefore, this paper delves into the coupled dynamics analysis of the underactuated double-pendulum marine tower crane system, and proposes a self-adapting trajectory tracking controller to compensate the dead zone constraint, unknown gravity forces as well as external disturbances. These techniques ensure precise tracking performance of desired trajectories and elimination of double-pendulum payload swing errors under harsh sea conditions. Lyapunov method is utilized to analyze and prove the stability of the whole closed-loop crane system, and the practicability of the proposed approach is also confirmed through numerous simulation results. • A self-adapting trajectory tracking controller has been designed for marine cranes with double-pendulum under harsh sea conditions. The proposed method effectively eliminates trajectory errors and quickly suppresses load oscillations. • To address some unknown gravity compensation, a novel online-adaptive law is designed to ensure the stability of the closed-loop system, with all output feedback terms proposed to. • The control force is considered with output constraints, which limits the amplitude and is beneficial for the actual control of the motor. [ABSTRACT FROM AUTHOR]