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As a widely-used technology, fluidized bed combustor (FBC) boiler is facing many control challenges such as coupling, high-order dynamics and nonlinearity. With more and more sustainable energy integrating into the bulk power system, the FBC boiler is obliged to speed up the respond to the automatic generation control command and this results in great challenges for keeping the bed temperature in the desired range. To this end, a modified active disturbance rejection control (MADRC) is put forward for high order systems with the type of K∕(Ts+1)n to enhance the control quality of the FBC boiler. Firstly, a simulation is carried out to discuss the estimation ability of the MADRC. A theorem about the stability analysis of the MADRC is provided and proofed theoretically. To help the field personnel to understand and use more easily, an effective tuning procedure is also concluded. Besides, a tuning toolbox based on the tuning procedure is established. Simulations and comparative experiments based on the Peltier temperature control platform validate the superiority of the MADRC, where the MADRC is able to enhance the control quality. Then the MADRC and other comparative controllers (the proportional integral controller and the regular ADRC) are designed for the FBC boiler. Simulation results illustrate that the MADRC can obtain the best performance. Statistical indices show that the MADRC has the smallest overshoot and shortest settling time. In addition, the MADRC still has the strongest ability to reject the input and coal quality variation disturbances. The advantages of the MADRC guarantee the high control quality and can be applied to industrial practice widely.

In recent years, a new water treatment technology based on microwave discharge electrodeless lamp (MDEL) has been developed. Hence, we designed an integrated system of microwave/electrodeless discharge ultraviolet/ozone (MW/UV/O3) for sewage sterilization according to the theoretical study of MDEL. The experiment was designed to test the ability to sterilize Escherichia coli and Bacillus subtilis by using different process conditions, such as single O3, MW/UV and MW/UV/O3, aiming to find an optimal process route. The results showed that the bactericidal effect of MW was mainly thermal effect, the bactericidal effect of MW/UV was significantly affected by turbidity, while the bactericidal effect of MW/UV/O3 was better than single O3 and MW/UV. In the dynamic test, when the four electrodeless UV lamps were stable, the light intensity reached 3.6 mW/cm2; when the aeration rate was 50 L/min, the generated O3 content was 0.30 mg/L. With a water flow of 800 L/h and hydraulic retention time of 1.5 min, a sewage sterilization rate of >99.99% was achieved by MW/UV/O3 system, and other water quality indexes including chemical oxygen demand (COD) and total organic carbon (TOC) in effluents was also decreased to some extents.

© 2019 Elsevier Ltd This paper proposes a novel bio-inspired optimization method named memetic salp swarm algorithm (MSSA). It is developed by extending the original salp swarm algorithm (SSA) with multiple independent salp chains, thus it can implement a wider exploration and a deeper exploitation under the memetic computing framework. In order to enhance the convergence stability, a virtual population based regroup operation is used for the global coordination between different salp chains. Due to partial shading condition (PSC) and fast time-varying weather conditions, photovoltaic (PV) systems may not be able to generate the global maximum power. Hence, MSSA is applied for an effective and efficient maximum power point tracking (MPPT) of PV systems under PSC. To evaluate the MPPT performance of the proposed algorithm, four case studies are undertaken using Matlab/Simulink, e.g., start-up test, step change of solar irradiation, ramp change of solar irradiation and temperature, and field atmospheric data of Hong Kong. The obtained PV system responses are compared to that of eight existing MPPT algorithms, such as incremental conductance (INC), genetic algorithm (GA), particle swarm optimization (PSO), artificial bees colony (ABC), cuckoo search algorithm (CSA), grey wolf optimizer (GWO), SSA, and teaching-learning-based optimization (TLBO), respectively. Simulation results demonstrate that the output energy generated by MSSA in Spring in HongKong is 118.57%, 100.73%, 100.96%, 100.87%, 101.35%, 100.36%, 100.81%, and 100.22% to that of INC, GA, PSO, ABC, CSA, GWO, SSA, and TLBO, respectively. Lastly, a hardware-in-the-loop (HIL) experiment using dSpace platform is undertaken to further validate the implementation feasibility of MSSA.

Metal-free photocatalytic aerobic hydroxylation of benzene to phenol is achieved by using the low-cost commercially available quinoline sulfate (QuH2SO4) as the photocatalyst. The reaction conditions are optimized and a high phenol yield of 11.3% is obtained under the optimal reaction conditions. It is found that the [QuH]+ cation is the catalytic active species and its planar structure is crucial for its effect interaction with benzene. Moreover, the influence of the coupled anion on the photocatalytic activity of the [QuH]+ cation is investigated and discussed.

Control of superheated steam temperature (SST) is becoming more and more challenging because of unknown disturbances caused by the frequent and extensive load changes and strict control requirements for the efficiency and safety. This is becoming even severe while the intermittent renewables penetration is growing. To this end, the working principle of SST is depicted and the models of SST are identified from the open-loop step response data. Considering the sluggish responses to the disturbances caused by high order dynamics, a modified active disturbance rejection control (ADRC) is proposed to enhance the control performance. Stability analysis of modified ADRC is derived theoretically to perfect the theory of modified ADRC. Then a practical tuning procedure is summarized for modified ADRC that can be readily understood by field engineers even though it involves trial and error tests. A simulation example shows that modified ADRC can improve the performance of tracking and disturbance rejection simultaneously while maintain a good robustness. A modified ADRC based cascade control strategy is proposed for the SST control system and the control performance is initially confirmed by a simulation based on the identified models. A field application in a 300 MW circulating fluidized bed (CFB) power plant demonstrates the advantages of the proposed strategy, which shows the temperature deviation can be significantly reduced in both the small-scale load varying condition and the large-scale load varying condition. The successful application of the proposed SST control system indicates a promising future of modified ADRC in power industry with the increasing demand on integrating more renewables into the power grid.

Many virtual try-on systems involve transferring and fitting garments to bodies of various shapes and postures, with grade preservation. To achieve this goal, garments must be treated as elastic models and their deformation is controlled by the laws of dynamics. Moreover, a collision-free state must be maintained during the simulation, as well as in the final draping state. We present a complete pipeline that concentrates on solving two problems: (1) deforming the target body towards the reference body, and (2) simulating the garment with robust handling of not only impending but also pre-existing collisions. Our solution to the first problem is a skeleton-driven framework, which consists of a collection of techniques, including skeleton embedding, skeleton posture alignment and skeleton-driven mesh deformation. For skeleton posture alignment, we decouple the orientation of each joint into two components: swing and twist, and align them separately. Treating garment models as rigid, the deformed target ‘fits’ into the garments with as few penetrations as possible. When solving the second problem, the body/garment penetrations are untangled along with cloth simulation, so that a collision-free state can be achieved. After that, the deformed target body restores its original shape gradually, while the garments are physically simulated to maintain a collision-free state, until a final draping state is reached on the fully restored target body. Examples show that the proposed framework is effective for garment transfer and fitness evaluation, and can be potentially used in applications like online shopping or customization.

Energy cooperation plays an important role in One Belt One Road (OBOR) initiative, which has attracted global attentions since it was firstly announced by China. However, studies focused on China-Myanmar energy cooperation under OBOR has not been explored yet, Myanmar usually acts as a geo-strategic link along OBOR while its power grid construction benefits from OBOR to a large extent. This paper aims to close this gap and provide a comprehensive analysis on China-Myanmar energy cooperation under OBOR. Current status of the two countries’ respective energy systems is investigated to show their motivations for cooperation. Then, SWOT analysis and PEST analysis are integrated to uncover the roots of the past or ongoing successful and unsuccessful energy projects, and to provide invaluable insights about opportunities and challenges caused by the most up-to-date global issues, including COVID-19 and U.S.-China trade war. Lastly, practical suggestions are given with respect to political, economical, social and technological domains, such that stakeholders, engineers, researchers and investors can adapt to the post-crisis era.

We show the existence of non-homothetic ancient flows by powers of curvature embedded in R 2 whose entropy is finite. We determine the Morse indices and kernels of the linearized operator of shrinkers to the flows, and construct ancient flows by using unstable eigenfunctions of the linearized operator.

Thermogenesis is a promising approach to limit weight gain in response to excess nutrition. In contrast to cold-induced thermogenesis, the molecular and cellular mechanisms of diet-induced thermogenesis (DIT) have not been fully characterized. Here, we explored the response of brown adipose tissue (BAT) and subcutaneous white adipose tissue (sWAT) to high fat diet (HFD) using proteome and phosphoproteome analysis. We observed that after HFD, Uncoupling protein 1 (UCP1) and its phosphorylation were only increased in BAT. Furthermore, proteins involved in fatty acid oxidation, tricarboxylic acid cycle, and oxidative phosphorylation were also upregulated in BAT. Nevertheless, most metabolic related proteins were downregulated in sWAT. We found that these metabolic changes accompanied with different variation of mitochondrial proteins between BAT and sWAT. After HFD, most mitochondrial proteins were decreased in sWAT, but not in BAT. This effect was correlated with decreased mitochondrial ribosomal proteins in sWAT. Finally, through phosphoproteomic analysis, we predicted the activities of kinases in HFD mice and observed that there were more kinases inactivated in sWAT. Finally, this dataset provides a valuable resource for molecular researchers in the fields of obesity and obesity-related disease. SIGNIFICANCE: Thermogenesis is a promising approach to combat obesity in response to excess energy. Nevertheless, the molecular and cellular mechanisms of DIT have not been fully characterized. Herein, we employed mass spectrometry (MS)-based proteomics and phosphoproteomics to identify differentially regulated proteins and phosphosites in BAT and sWAT of mice fed with HFD. This study unveils the differential regulatory networks of HFD in BAT and sWAT, which provides reference omics data to future researchers.

In this paper we classify all nonnegative extremal functions to a sharp weighted Sobolev inequality on the upper half space, which involves a divergent operator with degeneracy on the boundary. As an application of the results, we derive a sharp Sobolev type inequality involving Baouendi-Grushin operator, and classify certain extremal functions for all τ > 0 and m ≠ 2 or n ≠ 1 .

Low rate of extracellular electron transfer (EET) of exoelectrogens was a major bottleneck in restricting the performance of the microbial fuel cell (MFC) from practical applications. We used synthetic biology approaches (promoter and ribosome binding site (RBS) engineering, and cell surface engineering) to rationally design Shewanella oneidensis for enhanced flavins biosynthesis and transportation in a hydrophobic chassis to boost its EET rate and performance. Graphene oxide (GO) was subsequently used to construct an engineered Shewanella-reduced GO (rGO) 3D self-assembled biohybrid, which dramatically enhanced the thickness and cell numbers in the electroactive biofilm on the anode. Meanwhile, the absorption of flavins on the rGO sheets could not only enhance the π-π interaction, but also increase the local concentration of flavins, which could enhance electron shuttle (flavins)-mediated EET rate in the anodic biofilm. As a result, the maximum output power density reached 2.63 W/m2 (~18.8-folds higher than that of the wild-type S. oneidensis), the highest record of the electricity output of MFCs inoculated with S. oneidensis. Meanwhile, the inward current density of this 3D self-assembled biohybrid biofilm reached 18.78 A/m2.

Four different functional alkylimidazolium (1-hydroxyethyl-3-methylimidazolium, 1-carboxyethyl-3-methylimidazolium, 1-cyanopropyl-3-methylimidazolium and 1-benzyl-3-methylimidazolium) dibutyl phosphate ionic liquids were synthesized and used as lubricants for steel/Al alloy. The influence of functional groups on physicochemical properties and tribological properties was investigated and compared with 1-butyl-3-methylimidazolium dibutyl phosphate. As expected, viscosities increase when the functional groups are tethered to imidazolium cations. The tribological properties of the functional ionic liquids with three polar functional groups in cations are improved, especially the anti-wear performance and load-carrying capacity. On the contrary, the ionic liquid with benzyl group in cation shows worse tribological performance. It is considered that the functional groups in the imidazolium cations tune the adsorption of ionic liquids onto the alloy surface, which finally affect the tribological performance.

A facilely recyclable catalytic system towards liquid-phase reductant-free aerobic oxidation of benzene to phenol is built by simultaneously using graphitic carbon nitride (C3N4) and Ch5PMoV2. Especially, the hybrid Ch5PMoV2 is regarded as a temperature-controlled phase-transfer catalyst that prepared by modifying Keggin-type V-containing polyoxometalate anions (PMoV2) with choline (Ch) cations. The combined catalyst C3N4-Ch5PMoV2 shows a high activity with 10.7% phenol yield, 8.94 h−1 turnover frequency (TOF) and superior reusability under the optimized reaction conditions. Full characterizations and analyses including electron spin resonance spectroscopy (ESR), cyclic voltammetry (CV) and density functional theory (DFT) calculation are used to demonstrate the phase-transfer character and tuned redox property of Ch5PMoV2. Furthermore, a synergistic catalytic mechanism is proposed and discussed based on the experimental and DFT calculation results.

Gas sensing properties could be remarkably enhanced by self-assembly of zero, one or two dimensional nano-size units into three dimensional (3D) complicated superstructures. In this work, the 3D hollow indium oxide (In2O3) microspheres (HIOMs) assembled with porous 2D sheets were successfully synthesized by solvothermal method in Oleic acid (OA) and trioctylamine (TOA) system with the help of glycerine (Gl) combined with subsequent heat treatment. The density of self-assemble porous 2D nanosheet could be regulated by changing the calcination temperature from 400 °C to 600 °C. The gas-sensing performance of the as-prepared HIOMs had been measured towards unstable organic compounds containing methanol, acetone, ethanol, dichloromethane (DCM) and tetrahydrofuran (THF). Experimental results revealed that HIOMs-400 showed the highest response and selectivity to ethanol, followed by HIOMs-500 and HIOMs-600. At an ethanol concentration of 600 ppm, the HIOMs-400 sensor had a sensitivity of up to 15.6, while the sensitivity was about 11.9 for HIOMs-500 and 6.7 for HIOMs-600. HIOMs-400 also presented long term stability and repeatability even after five months. Such outstanding gas sensing properties of HIOMs-400 benefited from the larger BET surface area, denser pore structure and excellent capabilities of surface adsorbed oxygen.

Bacterial spoilage is an important reason causing freshness deterioration of fish during postmortem storage. The aim of this study is mainly to investigate the role of bacteria in freshness and the degradation of inosine 5′-monophosphate (IMP) as well as nucleotide derived values in chilled sturgeon (hybrid, Acipenser schrenckiid × Huso dauricus) fillets using a microbial reduction pretreatment. During storage at 4 or -1 °C, lower total bacterial count and total volatile base nitrogen in the treated samples was observed when compared to the control samples. But very close K, Ki value and IMP was observed in both groups, although higher IMP was recorded at day 6 and 9 at 4 °C. In later storage period, accelerated decrease of inosine (Ino) and increment of hypoxanthine (Hx) occurred in two control groups, resulting in a rapid increase of G and H values, significant higher than the treated groups. Six predominant spoilage bacteria (Acinetobacter johnsonii, Acinetobacter lwoffii, Shewanella baltica, Pseudomonas Fragi, Pseudomonas koreensis and Pseudomonas antarctica) were isolated from the sturgeon fillets during storage. Based on the results of respective co-cultivation of IMP with the six species, only Acinetobacter johnsonii had ability to degrade IMP when reached a high density of 2.84 × 109 CFU/mL. Results suggested that microbial reduction pretreatment could better the freshness of chilled sturgeon fillet. Comparing to endogenous IMPase, spoilage bacteria probably played a small role in IMP degradation, but affected considerably the decomposition of Ino to Hx.

A promising biochar-based catalyst was successfully developed from Jatropha curcas hull and de-oiled meal by incomplete carbonization and subsequent sulfonation. The catalysts were employed to produce functionalized blend components for low sulfur diesel. The catalysts were characterized by XRD, TG-DSC, BET, FT-IR and SEM. The characterization results revealed that the catalysts consisted of irregular, porous framework bearing abundant functional groups (–SO 3 H). The catalysts demonstrated high catalytic activity in transesterification, especially in esterification of free fatty acid (FFA). The superior catalytic activity was performed owing to high active sites density, large pores and loose irregular network of the catalysts, which facilitated mass transport of the reactant molecules and further enhanced the active sites accessibility. And the catalyst is fairly stable after five reaction recycles. The lubricating performance of the product was evaluated by high-frequency reciprocating test rig (HFRR). The findings indicated that methyl esters derived from Jatropha curcas oil were efficient enough to use as lubrication blend components and the average wear scar diameter (WSD) values of the sample fuel decreased progressively with the increasing of additive concentration.

Due to hygiene and safety requirements, much attention is given to microorganisms and biogenic amine (BA) in aquatic food. This study investigated microbial communities, BAs, and quality properties in abalone ( Haliotis discus hannai ) treated with sodium alginate coating (SAC) and bamboo leaf extract (BLE) or rosemary extract (ROE) stored under chill condition. Results showed that SAC with ROE improved sensory properties, delayed pH change and decreased total volatile basic nitrogen (TVBN), but BLE did not show significant effect. Putrescine and cadaverine were main BAs in abalone while no histamine was detected. Total BA was approximate 75 mg/kg, lower than recommended limit. SAC with ROE reduced the accumulation of putrescine, cadaverine and tyramine. Total viable count, Pseudomonas sp., H 2 S-producing bacteria, Enterobacteriaceae and lactic acid count were inhibited by SAC, and ROE enhanced the inhibition. Principal component analysis showed clear separation of groups with different coating treatments. Close Pearson correlations between putrescine, cadaverine and aforementioned four microbial communities were observed. Results indicate that SAC combined with ROE could effectively modify microbial composition in abalone, which in return decides final BA composition and level, pH value, TVBN content. They can be used for improving hygiene status and safety of chill stored abalone.

A facile, simple, and relatively environment-friendly hydrothermal approach was developed for one-step synthesis of graphitic carbon nitride nanosheets (GCNNs) using melamine and sodium citrate as the precursors. The prepared GCNNs emit strong fluorescence with a high quantum yield of 48.3%. The GCNNs were then characterized by various techniques including transmission electron microscopy, atomic force microscopy, X–ray diffraction, Fourier transform infrared spectroscopy, and UV–Vis absorption spectroscopy. In addition, the fluorescence quenching behavior of the GCNNS by mercuric ions (Hg 2+ ) was exploited to fabricate a label-free fluorescence quenching sensor for sensitive and selective detection of Hg 2+ . The results showed that there existed a linear relationship between the fluorescence intensity and the concentration of Hg 2+ from 0.001 to 1.0 μM with a detection limit of 0.3 nM. Finally, the sensor was successfully used to detection of Hg 2+ in water and milk samples.

In this paper, we prove that nonnegative polyharmonic functions on the upper half space satisfying a conformally invariant nonlinear boundary condition have to be the "\emph{polynomials} plus \emph{bubbles}" form. The nonlinear problem is motivated by the recent studies of boundary GJMS operators and the $Q$-curvature in conformal geometry. The result implies that in the conformal class of the unit Euclidean ball there exist metrics with a single singular boundary point which have flat $Q$-curvature and constant boundary $Q$-curvature. Moreover, all of such metrics are classified. This phenomenon differs from that of boundary singular metrics which have flat scalar curvature and constant mean curvature, where the singular set contains at least two points. A crucial ingredient of the proof is developing an approach to separate the higher order linear effect and the boundary nonlinear effect so that the kernels of the nonlinear problem are captured., Comment: fixed grammar errors; to be in J. Funct. Anal

Wind energy has the inherent nature of intermittence and randomness, such that its accurate prediction is extremely critical to ensure safe and stable operation of power system with increased wind power integration. This paper aims to present a thorough state-of-the-art one-stop handbook on various approaches applied in wind forecasting based on three perspectives: wind speed and power forecasting, uncertainty forecasting, and ramp events forecasting. Firstly, four classifications of wind data according to data source, along with twenty-seven data pre-processing technologies which can efficiently improve prediction precision are carefully addressed. Then, a systematic literature review of model principle based wind speed and power forecasting strategies is investigated, which is categorized into three groups: physical approaches, statistical approaches, and combined approaches. Peculiarly, it has reported that combined approaches can realize more than 70% accuracy improvement compared with single model. Besides, three novel technologies developed in recent years are also discussed, e.g., spatial correlation forecasting, regional forecasting, and offshore forecasting. Moreover, thirty-seven evaluation criteria of wind speed and power forecasting are thoroughly summarized for performance verification. Additionally, uncertainty forecasting and ramp events forecasting which can provide more risk information for operators to handle decision-making issues in power system are also elaborated. Lastly, eight recommendations for further development in wind forecasting are also proposed. The prominent merit of this work is that a total of one hundred and seven wind forecasting methods from three perspectives are comprehensively summarized and compared based on inputs, time-scale, space-scale, forecasting variables, metrics, and features, which aims to help readers more effectively utilize these approaches for future in-depth researches.

Energy storage system (ESS) has been expected to be a viable solution which can provide diverse benefits to different power system stakeholders, including generation side, transmission network (TN), distribution network (DN) and off-grid microgrid. Prudent ESS allocation in power grids determines satisfactory performance of ESS applications. Optimal sizing and placement of ESS are crucial for power quality improvement of DN and transmission system protection setting. To solve this issue, considerable researches have been done either in modelling or algorithms. However, various options and complex characteristics in different sub-systems make it difficult to appraise a specific method for an ESS application, while the existing reviews only focus on ESS applications in DN. This paper provides a critical one-stop handbook related to one hundred and four methods in six categories covering all kinds of networks and tailored applications. Meanwhile, a systematic methodology is presented with an extensive latest literature review, including ESS selection, evaluation criteria, modelling and solution methods. Particularly, different technical requirements and modelling methods of different sub-systems are outlined. Besides, pros and cons of optimization methods are thoroughly analysed and compared to reveal state-of-the-art studies. Finally, key points in optimal ESS sizing and placement are concluded along with recommendations for future research.

Multicomponent photocatalysts loaded with two interfacial co-catalysts may exhibit greater improvement in hydrogen evolution than those without any co-catalyst or with only one co-catalyst. Two major issues should be solved in developing such photocatalysts. One is how to obtain photocatalysts with two interfacial co-catalysts by a controllable approach. The other is what are key factors affecting photocatalytic activity. In this study, TiO2-based photocatalysts loaded with two interfacial co-catalysts, i.e., N-doped carbon layer coating on Au nanoparticle-embedded TiO2 and Au nanoparticles attaching on N-doped carbon layer coated TiO2, were prepared by thermal degradation of a Ti-based metal-organic framework, where the composition and interface sequence of N-doped carbon layer and Au nanoparticles were carefully engineered. Experimental results conclude that the Au/TiO2 interface, formed by a direct contact between Au and TiO2, is key factor to enhance the separation efficiency of photogenerated electrons/holes, and coating N-doped carbon layer on this Au/TiO2 interface achieves a synergistic effect in enhancing photocatalytic H2 production.

This paper is designed to undertake a comprehensive review on state-of-the-art maximum power point tracking (MPPT) methods of photovoltaic (PV) systems under partial shading condition (PSC). Particularly, the exploitation and utilization of various MPPT control approaches are of great significance to ensure a reliable and efficient maximum power extracting of PV systems. Hence, this paper systematically summarizes and discusses various MPPT algorithms utilized in PV systems under PSC, in which a total of 62 MPPT algorithms are elaborated, together with their modifications. Besides, they are categorized into seven groups, e.g., conventional algorithms, meta-heuristic algorithms, hybrid algorithms, mathematics-based algorithms, artificial intelligence (AI) algorithms, algorithms based on exploitation of characteristics curves, and other algorithms. Particularly, there are 25 meta-heuristic algorithms further divided into three categories for a more detailed discussion, namely, biology-based algorithms, physics-based algorithms, and sociology-based algorithms. In general, readers can make the most suitable choices according to application requirements and system specifications. This review can be regarded as a one-stop handbook for further studies in related field.

Close heterojunction interface, open diffusion channel and the reactivity of the exposed facet are three key factors that affect the photocatalytic activity of porous heterojunction materials. It is significant to study the influence of these three factors on the photocatalytic activity of metal-organic framework (MOF)-based heterojunction systems. Herein, we synthesized the TiO2@NH2-MIL-125(Ti) frame structure (TiO2@MOF FS) by in-situ self-sacrificial hydrolytic etching approach with directional chemical protection, where four exposed facets are all active NH2-MIL-125(Ti) {100} facets. According to the structural characteristics of NH2-MIL-125(Ti) {100} facets, tannic acid was selected as the directional protective agent, and NH2-MIL-125(Ti) was etched from the inside out by the hydrolysis method. The obtained TiO2@MOF FS possessed tight heterojunction interface between TiO2 and NH2-MIL-125(Ti), while maintaining the open diffusion channels of NH2-MIL-125(Ti). Benefited from the improved electrical conductivity, open diffusion channels and high reactivity of the exposed facets, the obtained TiO2@MOF FS showed excellent photocatalytic hydrogen production efficiency under sun light illumination, without the deposition of any noble metal co-catalyst. This work provides a novel research idea for the fabrication of highly efficient MOF-based photocatalysts.

A reliable and accurate mathematical modelling is crucial for performance analysis and optimal control of proton exchange membrane fuel cell (PEMFC) systems, which is mainly based on precise parameters estimation. With the significant computation advancement in the past decade, numerous meta-heuristic algorithms have been developed to solve such problem which have achieved quite promising results. Hence, this paper aims to undertake a comprehensive review on state-of-the-art meta-heuristic algorithms and related variants applied on PEMFC parameter estimation, which has greatly enhanced the diversity of algorithms compared with prior review. Note that over 160 literatures related to such problem are investigated for a systematic analysis and integration of relevant reported works. Particularly, these algorithms are classified into four categories, e.g., biology-based, physics-based, sociology-based and mathematics-based, upon which readers can systematically utilize these approaches to deal with PEMFC parameter estimation. Besides, various evaluation criteria, specific experimental performance, and other estimation techniques are also thoroughly discussed. Moreover, a thorough summary is carried out to systematically guide the readers to grasp and utilize these approaches. Lastly, some perspectives and recommendations are proposed in conclusion for future researches. In general, this paper can be regarded as a one-stop handbook for future in-depth researches in the related field.

Electrical energy storage system (EESS) plays a crucial role to handle the intermittency and randomness of renewable energy, such that the power reliability can be significantly enhanced. This paper attempts to design an adaptive fractional-order sliding-mode control (AFOSMC) approach for a typical EESS technology, e.g., superconducting magnetic energy storage (SMES) systems, to improve its dynamical responses against varirous operation conditions. At first, a sliding-mode state and perturbation observer (SMSPO) is applied to estimate the combined effect of unmodelled dynamics, parameter uncertainties, and external disturbances of SMES systems. Then, a fractional-order sliding-mode control (FOSMC) is utilized to completely compensate the perturbation estimat, such that a noticeable robustness can be achieved. Moreover, only the dq-axis currents need to be measured while the perturbation estimate replaces its upper bound, thus AFOSMC be easily achieved with appropriate control costs. For the purpose of validating its control performance, a distribution network involving SMES system with renewable energy penetration is studied. The control performance of conventional proportional-integral-derivative (PID) control, interconnection and damping assignment passivity-based control (IDA-PBC), sliding-mode control (SMC), and fractional-order sliding-mode control (FOSMC) is compared to that of AFOSMC under three scenarios. Simulation results show that AFOSMC can greatly outperform other approaches in both tracking speed and overall costs, e.g., its active power error is only 63.55%, 83.44%, 69.60%, and 76.67% of that of PID control, IDA-PBC, SMC, and FOSMC under reactive and active power supply, while the required control costs is only 76.69%, 91.28%, 83.50, and 86.76% to the above three controllers. Finally, a hardware-in-the-loop (HIL) test based on dSpace is implemented to verify its practicability under various scenarios.

Precise and reliable modelling of solid oxide fuel cells (SOFC) is critical for simulation analysis and optimal control of SOFC systems, which typically relies on an accurate identification of its unknown parameters. However, such problem is characterized by high non-linearity, multi-variable, and strong nonconvexity, thus conventional strategies cannot always achieve satisfactory results. With the rapid advancement of computer science, numerous meta-heuristic algorithms have been developed to solve such obstacle. However, there is no prior review to systematically summarize these approaches, thus a thorough survey study is absolutely needed. Hence, this paper undertakes a comprehensive survey on state-of-the-art meta-heuristic algorithms and related variants utilized in SOFC parameter identification. Besides, various specific experimental performance of each algorithm, and other latest estimation techniques are also elaborated. Moreover, a thorough summary is carried out to systematically compare and summarize their basic features, upon which readers can effectively grasp and utilize them. Lastly, some constructive perspectives and recommendations are proposed in conclusion for future researches. Note that hybrid variants can often achieve more satisfactory results than individual algorithms. Hence, the combination of various effective methods is crucial for novel parameter identification techniques development, upon which more reliable and efficient approaches can be devised for better simulation analysis and optimal control of SOFC systems. Besides, normalized models on such problem are also needed to be established for more accurate performance evaluation and prediction. In general, this paper can be regarded as a one-stop handbook for future in-depth studies in the related field.

Accurate parameter identification is crucial for a precise PV cell modelling and analysis of characteristics of PV systems, while high nonlinearity of output I-V curve makes this problem extremely thorny. Hence, a large number of researches have aroused extensive interests in the past few years. Due to the rapid advancement of computer technology and swarm intelligence, various promising meta-heuristic algorithms have been proposed to further accelerate this trend. This paper aims to undertake a comprehensive review on meta-heuristic algorithms and related variants which have been applied on PV cell parameter identification. Particularly, these algorithms are classified into four categories, e.g., biology-based algorithms, physics-based algorithms, sociology-based algorithms and mathematics-based algorithms. Meanwhile, the evaluation criteria and identification performance of each algorithm are thoroughly addressed. Besides, in order to quantitatively evaluate and compare various algorithms, the identified PV parameters including the specific error and the simulated output I-V or P-V curves are provided at the end of each algorithm. Moreover, a comprehensive summary is also introduced to more specifically guide the readers to grasp and utilize these approaches. Lastly, based on the covered twenty-eight algorithms, conclusion presents some perspectives and recommendations for future development.

The generation efficiency of thermoelectric generation system is relatively low, thus how maximize its power production is of great importance. This paper designs a novel greedy search based data-driven method for centralized thermoelectric generation system to achieve maximum power point tracking under non-uniform temperature distribution. In order to effectively distinguish the local maximum power points and the global maximum power point under non-uniform temperature distribution, greedy search based data-driven employs a two-layer feed-forward neural network to accurately fit the curve between the power output and the controllable variable based on the real-time updated operation data. Based on the approximation curve, a greedy search is designed to efficiently approach the global maximum power point from a shrinking search space. Cases studies such as start-up test, step variation of temperature, stochastic temperature change, and analyse of sensitivity, are implemented to prove the effectiveness and superiority of the proposed algorithm. Simulation results verify that the proposed method can generate the highest energy under non-uniform temperature distribution condition, e.g., 391.34%, 115.71%, 110.92%, and 109.43% to that of perturb and observe, particle swarm optimization, whale optimization algorithm, and grey wolf optimizer in the stochastic temperature change. Lastly, the implementation feasibility of the proposed method is demonstrated by the hardware-in-the-loop experiment based on dSpace platform.

In this paper, the through silicon via (TSV) blind holes with a diameter of 50 μm and a depth of 150 μm were prepared by MEMS micromachining technology. The Cu micro-cylinders (Cu-TSVs) were obtained by electrodepositing Cu in the blind holes using a direct current power. The mechanical properties of Cu-TSVs were measured using a self-made micro-compression system. The effect of current density on the mechanical property of Cu-TSVs was investigated. The experimental results indicated that when the current density increased from 1 mA/cm2 to 3 mA/cm2, the yield strength increased from 135.5 MPa to 177.6 MPa. However, when the current density further increased to 6 mA/cm2 and 9 mA/cm2, the yield strength decreased to 159.8 MPa and 119.3 MPa, respectively. Although it can improve the plating efficiency, the high current density led to the low yield strength. EBSD and XPS techniques were used to characterize the microstructure and impurities of Cu-TSVs. The grain size, grain boundary and grain orientation of Cu-TSVs electroplated at different current density were analyzed to discuss the mechanism.

Looming water crisis and labor shortage demand the shift from conventional transplanted rice (CTR) to dry direct seeded rice (DDSR). Hybrid rice varieties possess the potential to grow under DDSR system and can perform well even at low sowing rate. Present study investigated the yield responses of three hybrid rice varieties to different sowing rates and explored the physiological basis for grain yield formation under DDSR system. An inbred rice variety was grown as control. Results showed that reducing sowing rates of hybrid rice varieties from 240 seeds m −2 to 60 seeds m −2 did not reduce grain yield, while that of inbred rice varieties declined with decreasing sowing rates. Decreased sowing rates of inbred rice varieties recorded insufficient tillers, and lower panicle number that decreased their yield. Contrarily, for hybrid rice varieties grain yield was maintained even at reduced sowing rate because of their enhanced tillering capacity, higher specific leaf weight (SLW), and increased spikelet number per panicle (SPP), which might have compensated the reduced sowing rate. Our results suggested that the sowing rate of hybrid rice varieties can be reduced to 60 seeds m −2 without compensating yield of DDSR. However, adversities of low sowing rate in DDSR like weeds and poor stand establishment should be overcome to achieve maximum crop yield.

Classically, there are two major forms of cell death: necrosis, an unregulated digestion of cellular components; and apoptosis, a programmed mechanism that is promoted by caspases. However, another form of cell death has recently been identified that is inhibited by caspases, and yet occurs through a regulated mechanism, termed programmed necrosis or necroptosis. The biochemical basis of this program has begun to emerge, with the discovery of the receptor-interacting kinase RIP3 and its substrate, the pseudokinase mixed lineage kinase domain-like protein (MLKL), as core components. Furthermore, animal models have revealed significant functions for RIP3/MLKL-mediated necrotic cell death in immune responses against microbial infection and in the etiology of diseases involving tissue damage. This review discusses recent advances in our understanding of the mechanistic details and physiological functions of programmed necrosis.

New BiOI/Zn 2 SnO 4 p – n heterojunction photocatalysts were prepared by anchoring n-type Zn 2 SnO 4 nanoparticles on p-type BiOI plates. The physicochemical characteristics of the catalysts were studied by X-ray powder diffraction pattern (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), Ultraviolet visible (UV–vis) diffuse reflectance spectroscopy (DRS), nitrogen adsorption–desorption, and photoelectrochemistry measurement. The as-prepared catalysts exhibited excellent photocatalytic activity for the decomposition of methyl orange (MO) under visible light irradiation. The enhanced photocatalytic performance of BiOI/Zn 2 SnO 4 was not only attributed to the matched band potentials but also the interconnected heterojunction of BiOI and Zn 2 SnO 4 nanoparticles.

Summary Background & aims We aimed to examine the prevalence of obesity, abdominal obesity and associated factors in 17,656 Chinese hypertensive adults aged 45–75 years. Methods A cross-sectional investigation was carried out in Lianyungang, China. Overweight or obesity was defined as a body mass index of ≥25 kg/m2. Abdominal obesity was defined as a waist circumference ≥90 cm for men and ≥80 cm for women. Results The prevalence of overweight or obesity and abdominal obesity was 54.4% (women 59.3% and men 46.0%) and 59.4% (women 73.8% and men 35.1%), respectively. In the multivariable logistic-regression models, higher hypertension grades and standard of living, greater red meat consumption, lower physical activity levels, and antihypertensive treatment were independently associated with overweight or obesity and abdominal obesity in both sexes. Inland residence (versus coastal) was an independent associated factor for abdominal obesity in both sexes. Furthermore, a positive family history of diabetes in both sexes, a positive family history of hypertension, men with a positive family history of coronary heart disease, and men with inland residence were all independently associated with overweight or obesity. Conclusions We found a high prevalence of overweight or obesity and abdominal obesity in Chinese hypertensive adults, particularly in inland areas.

In this study, glycogen was extracted from oyster Ostrea talienwhanensis Crosse and used as a model to investigate the structure–activity correlation of polysaccharides. Purified oyster glycogen was characterized by methylation analysis, nuclear magnetic resonance (NMR) spectroscopy and infrared spectroscopy (IR). The oyster glycogen was subsequently sulfated by chlorosulfonic acid–pyridine method, and a C-6 substituted species (SOG) was identified to be the primary sulfated oyster glycogen species by 13C NMR spectroscopy. The molecular weight and sulfate content of the SOG was determined to be 3.2 × 104 g/mol and 33.6%, respectively. Another sulfated oyster glycogen species (SOG1) with C-2 and C-3 substitution was also identified at a lesser amount in the final product. SOG exhibited a much stronger stimulation effect to splenic lymphocyte proliferation than SOG1 in vitro, indicating that the position of sulfate substitution is a major determining factor on the efficacy of sulfated glycogens to stimulate lymphocyte proliferation.

We perform first-principles density function theory calculations to study the correlation between codoping forms and compensation mechanism in N–F pairs at ZnWO 4 (0 1 0) surface. Our study considers substitutional as well as adsorptive and interstitial codoping forms at ZnWO 4 (0 1 0) surface, and the results show that all the N s F s , N s F ad , N ad F s , and N ad F ad codoping forms can passivate the partially occupied states formed in the corresponding monodoped systems to enhance the photoactivity of ZnWO 4 (0 1 0) surface and decrease the transition energy of photoexcited electrons from the impurity levels to the conduction band minimum to low-energy area. There are four different compensation mechanisms in N–F pairs at ZnWO 4 (0 1 0) surface, corresponding to the four codoping forms, and different compensation mechanisms in N–F pairs result in different effects on photoactivity of ZnWO 4 , such as the N ad F ad has little sense to photocatalytic process, due to the electrons only transferring between the N ad –O b π * states. We expected that this knowledge could introduce some more general useful codoping concepts to the design of visible-light photocatalysts.

Soil ammonia volatilization induced by urea application at sowing negatively affects seed germination and early seedling growth of dry direct-seeded rice. Previous research suggests that ammonia volatilization can be reduced through nitrogen (N) management practices such as split application of urea, delaying the first urea application, and using N fertilizers which are less prone to volatilization. The objective of this study was to examine the impact of these N management practices on grain yield and nitrogen use efficiency of dry direct-seeded rice. Pot and field experiments were conducted under different N treatments. In the pot experiment, N treatments were 1.0 and 0.5 g N pot−1 as urea at sowing, 1.0 g N pot−1 as urea at 10 days after sowing (DAS), and 1.0 g N pot−1 as ammonium sulfate at sowing. In the field experiment five N treatments were used while keeping the total N rate as 150 kg N ha−1. These treatments included reducing the rates of urea applied at sowing from 90 to 60 and 30 kg N ha−1, delaying the first urea application to 10 DAS at 90 kg N ha−1, and application of ammonium sulfate as 90 kg N ha−1 at sowing. Reducing rate of urea applied at sowing, delaying the first urea application, or application of ammonium sulfate significantly increased plant growth, grain yield, above-ground N uptake and apparent N recovery (ANR) efficiency of dry direct-seeded rice, compared with higher rate of urea application at sowing. Here we demonstrate that by adoption of proper N management practices, a grain yield of above 6 t ha−1 can be achieved in dry direct-seeded rice production system. Such findings may greatly help in the wide spread of dry direct-seeded rice technology, particularly in central China.

( S )-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of ( S )-3,5-bistrifluoromethylphenyl ethanol was successfully performed in high enantiomeric excess (e.e.) through asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone catalyzed by Candida tropicalis 104 cells. The influence of some key reaction parameters such as substrate concentration, co-substrate and its concentration, biomass and reaction time was examined, respectively. The results showed that these factors obviously influence the yield, but the optical purity of the prepared product remains intact. The optimum conditions for the preparation of ( S )-3,5-bistrifluoromethylphenyl ethanol were found to be as follows: substrate concentration 50 mmol·L −1 ; 50 g·L −1 of maltose as co-substrate; wet cell concentration 300 g·L −1 ; reaction for 30 h. Under above optimal conditions, the maximum yield for ( S )-3,5-bistrifluoromethylphenyl ethanol reached 70.3% with 100% of product e.e.

Zinc oxide nanoparticles, with an average size of about 40 nm, were encapsulated by polystyrene using in situ emulsion polymerization in the presence of 3-methacryloxypropyltrimethoxysilane (MPTMS) as a coupling agent and polyoxyethylene nonylphenyl ether (OP-10) as a surfactant. Polymerization mechanism of nanocomposite latex was discussed. Transmission electron microscopy (TEM) proved the presence of ZnO nanoparticle appeared to be monodisperse in nanosize in polymer composite particles. ZnO/PS nanocomposites were characterized by Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results of FT-IR and XPS revealed that the surface of ZnO particle was successfully grafted by PS through the link of the coupling agent between ZnO and polymer. TGA and DSC results indicated an enhancement of thermal stability of composite materials compared with the pure polymer. SEM (scanning electron microscope) images showed a perfect dispersion of the ZnO particles in latex film. In addition, UV–visible absorption measurements demonstrated that the ZnO/PS composite coatings display a perfect performance of absorbing UV light.

In an attempt to understand the roles of apoptosis in the development of atherosclerosis, we classified lesions developed in the aortas of apo E- and LDL receptor-deficient mice, murine models of atherosclerosis, and determined frequency, spatial distribution and cell types of apoptotic cells in each lesion. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and nuclear staining with propidium iodide were used to demonstrate apoptotic cells. Mean frequencies of TUNEL-positive cells were as follows: 0%, in Type I, 0.3% in Type II, 0.05% in Type III, 0.06% in Type IV and 0.06% in Type V lesions. Most of the TUNEL-positive cells were filled with fat and distributed in close proximity to lipid pools. The TUNEL-positive cells in the intimal side of the lipid cores were macrophages, while some of those in the adventitial side were smooth muscle cells. In conclusion, apoptosis is involved in the active turn-over of foam cells of both macrophage- and smooth muscle cell-lineage especially in the early atherosclerotic lesions of the hyperlipidemic mice.

This article uses duopoly models and homogeneous production functions to analyze how one firm's wage rate will affect the other firm's systematic risk. Several interesting findings emerge; the following are the most relevant results: (1) A higher monopoly power of the duopoly decreases both firms' systematic risk. (2) An increase in one firm's wage rate will increase the other firm's systematic risk, but may increase, decrease, or have no effect on its own, depending on the properties of its production function and its competitor's reaction function. The second set of results is also applied to both monopoly and perfectly competitive market situations.

In a contribution in this Journal (38:93–104, 1986), Hawawini presented a geometry of risk aversion. However, there are two mistakes in his presentation that prevent him from correctly analyzing the interest and risk effects. In this article we develop a geometry that is both theoretically and geometrically consistent in order to conduct a comparative static analysis of the wealth, interest, and risk effects for CARA, DARA, and IARA.