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TiN/Ti multilayer coatings have great potential for application in improving aero-engine service lives in the sand environment. In this study, TiN/Ti multilayer coatings have been deposited on Ti6Al4V alloy by the magnetic filter cathode vacuum arc deposition technique. The microstructure, adhesion strength, microhardness and sand erosion properties of such coatings after different thermal cycling treatment at 500 °C have been characterized. The results showed that the adhesion strength decreased by 4.6, 4.6, and 41.5% for the coatings after treatments designated as 500-1, 500-2, and 500-3 (where 500 denotes the temperature in and -X denotes the number of cycles) compared with that of 500-0. The corresponding microhardness decreased by 13.5, 20.5, and 51.0%, and the erosion rate increased by factors of 2.51, 24.1, and 124.1. The degradation in mechanical properties was mainly attributed to the onset of surface oxidation, a loosening of the interface structure, and the development of interface microcracks. [ABSTRACT FROM AUTHOR]

Bisphenol A is a pollutant issued from the degradation of plastics such as polycarbonate and epoxy resins, yet actual bisphenol A monitoring in environmental samples is limited. Here we present the electrochemical detection of bisphenol A with a novel composite, MoS2–CoS2/reduced graphene oxide, obtained by a facile two-step hydrothermal process using MoS2 nanoflowers, CoS2 nano-polyhedrons and reduced graphene oxide. Results show that the linear range of the electrochemical sensor is wider, of 0.02–200 μM, and the detection limit is lower, of 2.5 nM, than actual electrochemical sensors. These findings are explained by good conductivity and the presence of abundant active sites. [ABSTRACT FROM AUTHOR]

Salmonella enteritidis is an important food-borne pathogen. The use of antibiotics is a serious threat to animal and human health, owing to the existence of resistant strains and drug residues. Lactic acid bacteria, as a new alternative to antibiotics, has attracted much attention. In this study, we investigated the antibacterial potential and underlying mechanism of Lactobacillus rhamnosus SQ511 against S. enteritidis ATCC13076. The results revealed that L. rhamnosus SQ511 significantly inhibited S. enteritidis ATCC13076 growth or even caused death. Laser confocal microscopic imaging revealed that the cell-free supernatant (CFS) of L. rhamnosus SQ511 elevated the reactive oxygen species level and bacterial membrane depolarization in S. enteritidis ATCC13076, leading to cell death. Furthermore, L. rhamnosus SQ511 CFS had severely deleterious effects on S. enteritidis ATCC13076, causing membrane destruction and the release of cellular materials. In addition, L. rhamnosus SQ511 CFS significantly reduced the expression of virulence, motility, adhesion, and invasion genes in S. enteritidis ATCC13076 (P < 0.05), and considerably inhibited motility and biofilm formation capacity (P < 0.05). Thus, antimicrobial compounds produced by L. rhamnosus SQ511 strongly inhibited S. enteritidis growth, mobility, biofilm formation, membrane disruption, and reactive oxygen species generation, and regulated virulence-related gene expressions, presenting promising applications as a probiotic agent. [ABSTRACT FROM AUTHOR]

This paper studied the electrical resistivity of in situ Cu-Fe microcomposites using theoretical analysis and experiments. The model alloys Cu-XFe (X = 3, 4.3, 11, 14 and 17 wt.%) were produced by casting, and the microcomposites were prepared by thermomechanical treatment. The solid solubility of iron in the copper matrix was measured using an energy dispersive spectrometer. The electrical resistivity and conductivity was evaluated using a micro-ohmmeter. The conductivity of the Cu-XFe (X = 3 and 4.3) was essentially constant at ~ 40% IACS. The conductivity of the Cu-XFe (X = 11, 14, 17) microcomposites decreased in a nonlinear manner with increasing iron content and increasing cold deformation strain, which was mainly determined by the interface scattering resistivity caused by the interface between the copper matrix and the iron fibers. [ABSTRACT FROM AUTHOR]

The dislocation slips during the hot- and cold-rolling processes, the texture evolution and the Goss-oriented grain refinement during the annealing of the Al–Cu–Mg alloy were investigated using optical microscope (OM), scanning electron microscope (SEM), electron back-scatter diffraction (EBSD), transmission electron microscope (TEM) and X-ray diffraction (XRD). Results shown that {111} <110> octahedral slip systems and {110} <111> non-octahedral slip systems can be activated during the hot- and cold-rolling. When the dislocation slips in {111} planes are suppressed, the cross-slip from the {111} planes to the {110} planes can be activated to coordinate deformation. The strain gradients between the adjacent grains of the alloy with the large cold rolling reduction during annealing are dramatically decreased by the strain homogenization, which suppresses the growth of {110} < 001 > Goss-oriented grains. The activation of {110} <111> slip systems may be led to the decrease of the intensity of {112} <111> Copper texture, and the effect of {110} <111> slip systems on the evolution of {001} < 100 > Cube texture is very small. With the increase of the cold rolling reduction and annealing temperature, the hardness of the annealed and rolled Al–Cu–Mg alloy all increases, strain hardening and grain refinement are responsible for the enhanced hardness. [ABSTRACT FROM AUTHOR]

The reduced graphene oxide supported Zn-doped Bi2MoO6 nanocomposites (ZnxBi2-xMoO6/RGO) are synthesized by an easy one-step solvothermal method for the rapid degradation of ciprofloxacin (CIP). Characterization analyses show that Bi2MoO6 nanosheets are uniformly supported on RGO, for which the agglomeration of Bi2MoO6 is effectively inhibited, leading to more exposure of surface active sites. The degradation rate of Zn0.1Bi1.9MoO6/RGO5 on CIP reached 90% after 120 min of visible light irradiation, which was 10.4 times the rate of unsupported Bi2MoO6. Zn doping and RGO loading synergistically reduce the recombination rate of photogenerated electron–hole pairs and result in the enhanced photocatalytic performance. Compared with previously reported catalysts, Zn0.1Bi1.9MoO6/RGO5 can get higher degradation efficiency with shorter time and less dosage. In addition, after five cycles, the degradation efficiency is maintained at about 85%, showing perfect cycling stability of Zn0.1Bi1.9MoO6/RGO5. Photocatalytic mechanism suggests that the photogenerated •O2− and h+ are main species for degrading CIP based on ZnxBi2-xMoO6/RGO complex. [ABSTRACT FROM AUTHOR]

Long-cycle stability and high-energy density are big challenges for developing high-performance hybrid supercapacitor (HSC) electrode materials. In this work, molybdenum-doped Co3O4 nanosheets arrays on nickel foam (noted as MoxCo1.5−xO/NF) are successfully prepared via facile one-step electrodeposition followed by annealing for hybrid supercapacitors. The experimental and calculated results indicate that the band gap modification and conductivity enhancement of MoxCo1.5−xO lead to excellent capacitive performance due to the doping of Mo into Co3O4. The as-prepared Mo0.25Co1.25/NF electrode demonstrates a high specific capacity of 128.2 mAh g−1 (923 F g−1) at 1 A g−1 (60% higher than the undoped Co3O4) and superior cycle stability with 95.2% capacity retention after 10,000 cycles at 10 A g−1. The assembled HSC delivers high-energy density of 64.3 Wh kg−1 at the power density of 794.1 W kg−1 and with 87.7% capacity retention after 10,000 cycles. This work can present a new strategy to fabricate the three-dimensional high-performance integrated electrode materials by a facile electrodeposition for heteroatom-doped transition metal oxide for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Evolution of microstructure, texture, and hardness of the Al-Cu-Mg alloy was investigated by using scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy, and x-ray diffraction. Results have shown that the hardness and Brass texture intensity of the Al-Cu-Mg alloy can be enhanced during the annealing process at 240-385 °C. The hardness enhancement of the alloy can be attributed to the fine-grain strengthening; the enhancement of the Brass texture intensity of the alloy is related to the polygonization of the deformed grains with Brass orientation. In addition, the evolution path of the Brass texture evolving into recrystallization texture during annealing can be summarized as follows: Brass texture → Goss texture → R-Goss texture → Cube texture. [ABSTRACT FROM AUTHOR]

A ternary visible light-driven catalyst, reduced graphene oxide (RGO)-based Bi2MoO6 (BMO), modified with CdS, was synthesized for the degradation of ciprofloxacin through solvothermal method. Neither toxic reductant nor toxic solvent was used. The structural characterization shows that graphene oxide sheets were reduced, while BMO nanoplates and CdS nanoparticles grew to form CdS–BMO/RGO simultaneously. The modification of BMO with CdS and RGO extraordinarily enhances the photocatalytic performance of BMO on the degradation of ciprofloxacin (CIP) under visible light irradiation. The photodegradation rate of CIP over CdS–BMO/RGO photocatalyst is approximately 24 times faster than that of BMO. The improvement of the photocatalytic performance is attributed to the synergistic effect among CdS, BMO and graphene. Moreover, CdS–BMO/RGO exhibits better performance on the degradation of CIP than most bismuth oxide-containing catalysts recently reported. Degradation of various organic contaminants in addition to CIP has also been studied, showing that CdS–BMO/RGO exhibits much higher photocatalytic performance on degrading molecules containing smaller conjugated system. [ABSTRACT FROM AUTHOR]

Though it is well recognized that the space between graphene cover and the metal substrate can act as a two-dimensional (2D) nanoreactor, several issues are still unresolved, including the role of the metal substrate, the mechanisms ruling water intercalation and the identification of sites at which water is decomposed. Here, we solve these issues by means of density functional theory and high-resolution electron energy loss spectroscopy experiments carried out on graphene grown on (111)-oriented Cu foils. Specifically, we observe decomposition of H2O at room temperature with only H atoms forming bonds with graphene and with buried OH groups underneath the graphene cover. Our theoretical model discloses physicochemical mechanisms ruling the migration and decomposition of water on graphene/Cu. We discover that the edge of graphene can be easily saturated by H through decomposition of H2O, which allows H2O to migrate in the subsurface region from the decoupled edge, where H2O decomposes at room temperature. Hydrogen atoms produced by the decomposition of H2O initially form a chemical bond with graphene for the lower energy barrier compared with other routes. These findings are essential to exploit graphene/Cu interfaces in catalysis and in energy-related applications. [ABSTRACT FROM AUTHOR]

Magnetically separable reduced graphene oxide (RGO)-based ZnFe mixed metal oxide (MMO) nanocomposite (MMO/RGO) was prepared via a scalable and low energy-consuming co-precipitation-calcination process. The preparation procedure can be easily carried out at lower temperature in shorter time compared with those reported in literatures. The structural characterization indicates that ZnFe MMO (i.e., ZnO/ZnFe2O4) heterojunctions are homogeneously distributed as particles with a size in the range of 5–30 nm on the surface of RGO. The ZnFe MMO/RGO nanocomposite exhibits superior photocatalytic performance and stability for the degradation of tetracycline (TC) under visible-light illumination. 100% of the TC molecules is removed after visible-light irradiation for 120 min at 25 °C in the presence of ZnFe MMO/RGO. The photodegradation rate constant is 3.4 times that of ZnFe MMO, suggesting that the synergistic effect between ZnFe MMO and RGO improves the photocatalytic degradation performance of the nanocomposites. Neither toxic chemical reductants nor additional solvents were used during the preparation. More importantly, ZnFe MMO/RGO nanocomposite can be easily recycled by applying an external magnet. This work may provide an environment-friendly low-energy consuming method for large-scale production of MMO/RGO photocatalysts toward the degradation of TC. The photocatalytic mechanism of the ZnFe MMO/RGO nanocomposite was also investigated. [ABSTRACT FROM AUTHOR]

A ternary reduced graphene oxide based Bi2O2CO3/BiOCl (rBB) composite was prepared for the first time via a facile hydrothermal approach. The composite has a carnation-like morphology and consists of self-assembled nanoplates. Due to the unique structure and synergistic effect existing among reduced graphene oxide (rGO), Bi2O2CO3 and BiOCl nanoplates, the rBB composite exhibits good photocatalytic activity toward the degradation of ciprofloxacin, which is much higher than that of previously reported oxygen-containing bismuth compound photocatalyst. The combination of rGO with Bi2O2CO3/BiOCl greatly improves the visible-light-driven catalytic activity of the composite with the highest degradation efficiency achieved at a rGO content of 1.0 wt%. 83% of the degradation efficiency can be retained after five cycles, and no obvious decrease is observed from the third cycle. Photogenerated holes and hydroxyl radicals are proved to be the major oxidative species in the degradation. The photocatalytic performance of rBB toward degradation of Tetracycline, Methyl Blue and Rhodamine B is also found quite desirable, making rBB a promising broad spectrum photocatalyst. [ABSTRACT FROM AUTHOR]

An antibacterial nanocomposite, reduced graphene oxide-based copper oxide (CuO-RGO), was prepared by a one-step hydrothermal method and characterized by x-ray diffraction analysis, infrared absorption spectroscopy, scanning electron microscopy, transmission electron microscopy, and photoluminescence measurements, revealing CuO nanoparticles with diameter of about 26 nm uniformly anchored on graphene sheets. Compared with recently reported bacteriostatic agents, much less CuO-RGO is required and better bacteriostatic effect is achieved, with good stability. The minimum inhibitory concentration of the CuO-RGO composite against Escherichia coli reached 240 μg mL−1. The antibacterial rate remained at 89% after five cycles. In addition, introduction of graphene inhibited leaching of Cu2+, which reduces the cytotoxicity of CuO-RGO to mouse fibroblast L929. [ABSTRACT FROM AUTHOR]

A novel visible-light-driven photocatalyst Bi2WO6/Ag2O/CQDs (BWO/Ag2O/CQDs), which possesses hierarchical superstructure with marigold-like appearance, was fabricated via a hydrothermal method, followed by a simple precipitation process. Ag2O nanoparticles sized around 25 nm and CQDs with diameters of about 10 nm were evenly deposited on Bi2WO6 to form a unique heterostructure. The obtained BWO/Ag2O/CQDs heterostructure showed excellent adsorption and remarkably enhanced photocatalytic performance in the photodegradation of antibiotic tetracycline (TC) under visible-light irradiation compared to pristine Bi2WO6. The degradation rate of TC over BWO/Ag2O/CQDs photocatalyst is 16.2 times higher than that of pristine Bi2WO6 and a possible mechanism for the enhanced photocatalytic performance was discussed. In addition, BWO/Ag2O/CQDs was applied in the selective oxidation of benzyl alcohol to benzaldehyde under visible-light illumination. The result demonstrated that the conversion rate and product selectivity are greatly improved over BWO/Ag2O/CQDs compared to pristine Bi2WO6 in the same reaction conditions, making it a promising photocatalyst in the application of green chemical transformation. The co-coupling of CQDs and Ag2O with matched band potentials gives a substantial promotion for the light harvesting ability and effective separation of photogenerated charge carriers, synergistically accounting for the improvement of photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

Here, we report a simple approach to fabricate 3D hierarchical peony-like Ag/BiWO hybrid photocatalyst through one-step hydrothermal method with l-leucine as a template. The morphology and structure of the resultant materials were characterized by various analytical methods, such as X-ray diffraction, field emission scanning electron microscopy and UV-Vis diffuse reflectance spectra. The photocatalytic performance of BiWO and Ag/BiWO samples was evaluated by degrading organic dye and antibiotic in water under visible light irradiation. A series of results indicated that loaded Ag nanoparticles significantly improve the photocatalytic activity of BiWO. In addition, the possible mechanism was proposed that the enhanced photocatalytic activity was resulted from the unique configuration of peony-like morphology that favorable for the adsorption of organic compounds and the high Schottky barriers between interface of Ag NPs and BiWO, which promoted the transfer of photogenerated electrons from BiWO to Ag NPs. Meanwhile, noble metal Ag can induce surface plasmon resonance leading to the better visible light absorption of BiWO. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenation of nitrophenols to aminophenols was considered as the most efficient way to solve their contamination together with huge economic benefit. NiCoS can be used not only as supercapacitor materials, but also competitive catalytic materials in hydrogenation reactions. In this work, a nitrogen-doped carbon black (NCB) supported NiCoS catalyst is successfully prepared by a facile one-pot solvothermal approach. TEM results show that the ultrafine NiCoS particles are uniformly dispersed on the surface of NCB at a low NiCoS loading, while aggregation may occur in NiCoS/NCB catalysts with an excessive NiCoS content. The NiCoS-30/NCB catalyst with a BET surface area of 47.20 m g exhibits the most excellent catalytic activity and durability for heterogeneous catalytic hydrogenation of nitrophenols using NaBH as the reducing agent at 30 °C in the aqueous solution. The kinetic constant of hydrogenation of p-nitrophenol catalyzed by NiCoS-30/NCB is almost five times higher than the reaction catalyzed by pristine NiCoS. The outstanding performance of NiCoS-30/NCB is ascribed to the unique nanostructure of the catalyst and the combined effect between the NiCoS and NCB, including abundant surface functional groups of NCB for anchoring and dispersing NiCoS, strong adsorption ability for nitrophenol molecules facilitated by π-π stacking interaction, as well as fast electron transfer from NCB to NiCoS, resulting in higher local electron densities and thus facilitating the uptake of electrons by nitrophenols. [ABSTRACT FROM AUTHOR]

A magnetically separable FeO@BiO-RGO core-shell heterostructured photocatalyst was successfully prepared through a self-assembly method for the first time. The FeO nanoparticles with an average diameter of 200 nm was wrapped by approximately 50 nm thick layer of BiO to form unique FeO@BiO nanospheres, then loaded on the surface of reduced graphene oxide (RGO). Compared with pure BiO and FeO@BiO, the as-synthesized FeO@BiO-RGO nanocomposites showed broadened visible light adsorption range, increased charge separation efficiency, excellent photocatalytic activity and cyclic stability for degradation of quinolone antibiotics (QAs) under visible light irradation. The degradation rate of ciprofloxacin (CIP) with FeO@BiO-RGO photocatalyst could reach 98.3% in 240 min and it was still above 80% after ten photocatalytic reaction cycles. More importantly, benefiting from the introduction of FeO and RGO, the FeO@BiO-RGO nanocomposites could effectively prevent the rapid recombination of photogenerated electron-hole pairs and photocorrosion phenomenon of BiO, which made it become a highly stable and durable photocatalyst. These attractive features make the FeO@BiO-RGO nanocomposites to be a promising photocatalyst for visible light photocatalytic degradation of QAs in water pollutants treatment. [ABSTRACT FROM AUTHOR]

We present an improved geometric model of faulted detachment folding with pure shear that is characterized by core thickening and a ramp-discordant backlimb. The model includes a two-stage evolution: 1) detachment folding involving pure shear with fixed hinges, and 2) faulted detachment folding, in which the core of anticline thrusts above a break-through fault in forelimb by limb rotation. The growth strata patterns of the model are also discussed with respect to factors such as limb rotation, tectonic uplift rate, and sedimentation rate. A thrust-related fold, called a TBE thrust fold, in the Tarim Basin in NW China, is analyzed as an example of the theoretical model. The result indicates that the TBE thrust fold has undergone a two-stage evolution with shortening of a few hundred meters. Both the theoretical model and the actual example indicate that the shortening in the detachment folding stage takes up a large proportion of the total shortening. The structural restoration of the TBE thrust fold also provides new evidence that the formation of a series of thin-skinned structures in the SE Tarim Basin initiated in the Late Ordovician. The model may be applicable to low-amplitude faulted detachment folds. [ABSTRACT FROM AUTHOR]

Due to the unique electronic properties and high adsorption capacity of graphene, a facile strategy was developed to form graphene/melamine nanocomposite by anchoring melamine molecule on the surface of graphene sheets. As the electrostatic attraction happened between protonated melamine and negatively charged bisphenol A (BPA), a novel electrochemical sensor was fabricated to determine the endocrine disruptor BPA by depositing graphene/melamine nanocomposite on the surface of glassy carbon electrode. The electrochemical behavior of BPA was investigated in phosphate buffer solution (pH 7.0) using the prepared sensor. A well-defined anodic peak at 0.56 V was found to attribute to the electrooxidation of BPA on the modified electrode. The kinetic parameters, charge transfer coefficient, electron transfer number, proton transfer number, and standard rate constant were calculated and optimized. The electrochemical sensor exhibited a wider linear range of 1.0 × 10 to 2.0 × 10 M BPA and a lower detection limit of 4.0 × 10 M ( S/ N = 3). This novel sensor was successfully applied to determine BPA leached from real plastic samples with good recoveries ranging from 97.00 to 100.96 %. [ABSTRACT FROM AUTHOR]

In order to predict the detonation velocity of high-nitrogen compounds, the following calculated descriptors, Q, ρ, and Δ E of 54 high-nitrogen compounds were calculated using DFT-B3LYP method with the 6-31G** basis set, which were then used to build the linear and nonlinear multivariable models by multiple linear regression (MLR) and least square support vector machine (LS-SVM) methods, respectively. It turned out that the two models, whose stabilities were confirmed using the leave-one-out validation, were able to describe about 95.5 and 96.2% of the variance of the experimental values, respectively. External validation was carried out with R and Q values of 0.921, 0.911, 0.971, and 0.955, respectively. Moreover, the results of the Y-randomization test revealed that there were no chance corrections among the data matrix. These results coupling theoretical calculations and QSPR methods can be complementary to experimental tests, providing guidance for the management of chemical explosive hazards. [ABSTRACT FROM AUTHOR]

This paper proposes an assessment framework for branch parameter estimation of power systems, based on which the estimation accuracy can be improved and the estimation reliability can be ensured. The proposed framework comprises three parts: 1) Parameter credibility assessment to evaluate the credibility of original parameters in the case that their true values are unknown; 2) estimation accuracy assessment to provide quantitative information about the validity of the estimation; 3) parameter dominance assessment to find out the key parameters for the estimation. This framework can be incorporated into the conventional parameter estimation process easily such that the accuracy and reliability of the estimation are improved. The implementation problems are addressed in details. Tests are carried out on the IEEE 14-bus system, IEEE 30-bus system, and IEEE 300-bus system to show the correctness and effectiveness of the proposed assessment framework. [ABSTRACT FROM AUTHOR]

Based on high-resolution 2D seismic profiles, the Paleozoic structural deformation characteristics of Bachu (巴楚) uplift of northwestern Tarim basin, NW China, are exhibited in this article. The deformation happened during three main geological periods: the end of Middle-Late Ordovician (O2–3), the end of Early-Middle Devonian (D1–2), and the end of Late Permian (P2). In the Bachu uplift, there developed a series of NW-trending thrust faults and imbricate structures due to the effect of the NW-SE compression stress towards the end of Middle-Late Ordovician (O2–3) (middle Caledonian movement), and there developed some NNE-trending thrust faults and fault blocks under the control of the NEE-SWW compression stress at the end of Early-Middle Devonian (D1–2) (early Hercynian movement). However, at the end of Late Permian (P2) (late Hercynian movement), some NE-trending thrust faults and associated folds developed as a result of the NE-SW compression stress. The first-stage (O2–3) deformation is obviously more violent than those of the latter two stages (D1–2 and P2), which implies that the Tarim plate drifted quickly to the north at around the same time basin. [ABSTRACT FROM AUTHOR]

Traditional energy management system (EMS) plays an indispensable role in control centers of electric power systems. However, it also has several shortcomings, including lack of real-time closed-loop control, unreliable functional modules, and difficult to exchange data. The electric hybrid control theory (EHCT) has been proposed as an innovative and effective means to overcome these shortcomings. This paper argues that the EHCT provides a theoretical foundation for the advanced energy management system (AEMS) that can achieve multi-objective, near-optimal, and closed-loop control of electric power grids. This paper also discusses the significance for control centers to evolve from the traditional EMS to the AEMS. Furthermore, this paper points out that the traditional EMS can be considered as an integral part of the AEMS and that the AEMS can be built upon the traditional EMS. Thus, the resources that are currently available can be fully utilized to achieve near-optimal and closed-loop control of power system operations. [ABSTRACT FROM AUTHOR]

The narrow definition of the digital power system (DPS) is proposed. The architecture, features and key contents of the DPS are presented, which include intelligent dispatching system, hybrid automatic control system and data sharing platform. The successful construction of the DPS can greatly improve the performances of power system operating and dispatching, which mainly reflect a fundamental increase of the ability of avoiding catastrophes resulting from blackouts of power supply, a significant improvement of economic efficiency of power system operation, and an improvement of decision efficiency of power system developing. The DPS describes a vision of the development of power system and the way to achieve this vision. At the same time, the paper also proposes the principles of the design and implementation of the DPS. [ABSTRACT FROM AUTHOR]

To meet the demand of high stability, high quality, and low losses of power systems, the advanced energy management system (AEMS) is established and revealed in this bulletin, which has been put into trial operation in Shanghai power system for almost half a year. The AEMS is novel from all aspects covering idea, theory, method, software, and engineering. The essence of AEMS is exercising the hybrid automatic control theory and technology to realize multi-objective optimal closed-loop control of power systems. Based on an “event-driven” strategy, the AEMS transforms multi-objective optimal control problems into event identification and elimination by defining the unsatisfactory states of a power system as events. This bulletin concisely presents the theory and main advantages of AEMS, as well as its implementation in Shanghai power system. [ABSTRACT FROM AUTHOR]

The fractional calculus approach in the constitutive relationship model of second-order fluid is introduced and the flow characteristics of the viscoelastic fluid in double cylinder rheometer are studied. First, the analytical solution of which the derivative order is 1/2 is derived with the analytical solution and the reliability of Laplace numerical inversion based on Crump algorithm for the problem is verified, then the characteristics of second-order fluid flow in the rheometer by using Crump method is analyzed. The results indicate that the more obvious the viscoelastic properties of fluid are, the more sensitive the dependence of velocity and stress on fractional derivative order is. [ABSTRACT FROM AUTHOR]

A composite was prepared at room temperature from nitrogen-doped reduced graphene oxide (N-rGO) and melamine via π-interaction. An ultra-sensitive electrochemical sensor for the determination of trace levels of bisphenol A (BPA) was obtained by coating a glassy carbon electrode (GCE) with the composite. The structure and morphology of composite were characterized by FTIR, Raman, XRD, XPS, SEM and TEM. Because of the synergetic effects of N-rGO and melamine, the modified GCE displays considerably enhanced sensitivity to BPA. The voltammetric response, typically measured at a peak of 0.48 V (vs. SCE) is linear in the 0.05 to 20 μM BPA concentration range, and the detection limit is 0.8 nM (at S/N = 3). The sensor is reproducible, stable and selective. It was applied to analyze baby bottles, drinking cups, mineral water bottles and shopping receipts that were spiked with BPA, and the recoveries reached 99.1-101.4%.Illustration of fabricating the electrochemical sensor for detecting BPA. N-G/M: nitrogen-doped reduced graphene oxide and melamine composite; GCE: glassy carbon electrode [ABSTRACT FROM AUTHOR]