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The amount of substation accident oil pool wastewater (SAOPW) generated has been increasing due to the successive addition and renovation of substations, and the discharge of untreated or incomplete treatment outside the station will cause serious environmental pollution problems. In this study, a polyethersulfone (PES) composite ultrafiltration membranes were fabricated using phase inversion method and evaluated them for oil removal from SAOPW. The morphology and functional groups of PES composite membranes before and after filtration were characterized and compared through scanning electron microscopy and Fourier-transform infrared spectroscopy. The effects of operating pressure, feed temperature, initial oil concentration and operating time were systematically investigated using flux recovery and oil removal rate as the indexes of investigation, and the process economy was studied and evaluated. The results showed that the PES composite membrane had a relatively high-water flux of 260.2 (L·m-2·h-1) and a high oil removal rate (≥90%), which could effectively remove oil from water. Besides, its high flux recovery ratio (≥90%) after four filtration and cleaning cycles indicated the excellent performance of this PES composite membrane in the separation of oil--water emulsions. This study confirms the applicability of PES composite membrane for oil removal from SAOPW, providing a promising treatment method for the SAOPW treatment. [ABSTRACT FROM AUTHOR]

The cutting saw blade with diamond blade and carbon steel matrix is widely used in stone cutting because of its high strength, impact resistance and good thermal stability. However, the carbon steel matrix is easy to corrode in the circulating cooling water, which shortens its service life. In this study, a new highly efficient benzotriazole-based (BMN) composite inhibitor was synthesized and investigated against the corrosion of carbon steel in stone processing wastewater. The corrosion inhibition properties and mechanism of prepared BMN for carbon steel in real stone processing wastewater were evaluated and deduced using the experimental weight loss, electrochemical and surface morphology characterization techniques. Weight loss methods results showed that a high inhibition efficiency of 99.59% in stone processing wastewater was achieved at ambient temperature, with the stirring speed 200 rpm, the immersion time 7 d, and the BMN concentration is 50 mL·L–1. Electrochemical impedance spectroscopy indicated that resistance from the surface films (R2 ) and charge transfer resistance (R3 ) were enhanced with increase in BMN concentration. Polarisation results revealed the BMN acted as an anodic inhibitor, owing to the addition of BMN resulted in the significant change of anodic Tafel slopes (βa ). Scanning electron microscopy results indicated BMN formed a protective film on the surface of carbon steel through adsorption. In short, the prepared BMN composite inhibitor exhibited superior anti-corrosion performance for saw blade corrosion in stone processing wastewater, which had great application potential in industries. [ABSTRACT FROM AUTHOR]

The design of a highly efficient system for CO2 photoreduction fully based on earth-abundant elements presents a challenge, which may be overcome by installing suitable interactions between photosensitizer and catalyst to expedite the intermolecular electron transfer. Herein, we have designed a pyrene-decorated Cu(I) complex with a rare dual emission behavior, aiming at additional π-interaction with a pyrene-appended Co(II) catalyst for visible light–driven CO2-to- CO conversion. The results of 1H NMR titration, time-resolved fluorescence/absorption spectroscopies, quantum chemical simulations, and photocatalytic experiments clearly demonstrate that the dynamic π–π interaction between sensitizer and catalyst is highly advantageous in photocatalysis by accelerating the intermolecular electron transfer rate up to 6.9 × 105 s−1, thus achieving a notable apparent quantum yield of 19% at 425 nm with near-unity selectivity. While comparable to most earth-abundant molecular systems, this value is over three times of the pyrene-free system (6.0%) and far surpassing the benchmarking Ru(II) tris(bipyridine) (0.3%) and Ir(III) tris(2-phenylpyridine) (1.4%) photosensitizers under parallel conditions. [ABSTRACT FROM AUTHOR]

Distributed drive electric vehicle with four in-wheel motors is widespread with various characteristics, such as performance potentials for independent wheel drive control and energy efficiency. However, in future, one of the biggest obstacles for its success in the automotive industry would be its limited energy storage. This paper proposes a hierarchical control method that involves a high-level motion controller that uses sliding mode control to calculate the total desired force and yaw moment and a low-level allocation controller in which an optimal energy-efficient control allocation scheme is presented to provide optimally distributed torques of four in-wheel motors in all the normal cases. A practicable motor energy efficiency model as a motor actuator is proposed by incorporating the electric motor efficiency map based on measured data into the motor efficiency experiment and a current closed-loop motor model. Moreover, both tracking performance and energy-saving are carried out in this research and evaluated via a co-simulation approach using MATLAB/Simulink and CarSim. A ramp maneuver at a constant speed and New European Driving Cycle and Urban Dynamometer Driving Schedule maneuvers have been conducted. To conclude, it is demonstrated that distributed drive electric vehicle with four in-wheel motors can reduce total power consumption and enhance tracking performance compared with a simple control allocation in which the torques are the fixed ratio distribution. [ABSTRACT FROM AUTHOR]

Starch is one of the most popular nutritional sources for both human and animals. Due to the variation of its nutritional traits and biochemical specificities, starch has been classified into rapidly digestible, slowly digestible and resistant starch. Resistant starch has its own unique chemical structure, and various forms of resistant starch are commercially available. It has been found being a multiple-functional regulator for treating metabolic dysfunction. Different functions of resistant starch such as modulation of the gut microbiota, gut peptides, circulating growth factors, circulating inflammatory mediators have been characterized by animal studies and clinical trials. In this mini-review, recent remarkable progress in resistant starch on gut microbiota, particularly the effect of structure, biochemistry and cell signaling on nutrition has been summarized, with highlights on its regulatory effect on gut microbiota. [ABSTRACT FROM AUTHOR]

Three kinds of novel indium oxide (In2O3) nanostructures, namely, nanorods, nanoflowers and nanowhiskers were synthesized on silicon substrate via a simple vapor‐phase transport method under atmospheric pressure. The In2O3nanostructures were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectrometer (EDS) spectrum. The Raman spectra of these nanostructures showed four sharp scattering peaks centered at 308, 365, 522, and 628 cm‐1, whose position and intensity were characteristic of standard Raman spectra for In2O3. The Room‐temperature photoluminescence (PL) spectra showed visible emissions centered around 576, 592, and 624 nm. Field emission measurements demonstrated that the nanoflowers possessed the best performance with a turn‐on field of 3.54 V/µm and a threshold field of 9.83 V/µm. And the field enhancement factors of these nanostructures are high enough for the application of field emission display devices. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Three novel kinds of hierarchical ZnO nanostructures: nanocombs nanoscrewdrivers and nanonails, have been synthesized in large quantities via a simple thermal evaporation process in the same run of growth in different regions of the quartz tube. The morphologies could be well controlled by adjusting the distances between the source materials and the substrates. These ZnO products were investigated by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The field emission properties of the ZnO nanostructures were investigated. These hierarchical ZnO nanostructures may be attractive building blocks for field emission microelectronic devices and other devices. [ABSTRACT FROM AUTHOR]

In order to investigate the expression of cyclooxygenase-2 (COX-2) in human lower segments of myometrium obtained from women in labor and those not in labor and identify the splicing variant of COX-2, reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect the expression of COX-2. The primers were designed and synthesized according to the sequence of rat COX-2 splice variant which was discovered firstly by us. Then the splicing variant of COX-2 in human myometrium from woman in labor was identified, cloned into vector and sequenced. The results showed that the expression of COX-2 mRNA was lower in human myometrium obtained from women who were not in labor than that in labor women and a new band of COX-2 was obtained in myometrium from labor woman. The fragment included an unspliced intron, which pitched between exons 7 and 8. It was suggested that COX-2 gene was not only expressed highly in human myometrium from woman in labor, but also produced splicing variant by alternative splicing. [ABSTRACT FROM AUTHOR]