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With the large-scale configuration of distribution automation and the widespread implementation of distributed generation (DG) and flexible load (FL), the distribution network can achieve active regulation, which makes the traditional fault restoration strategy and distribution network reliability evaluation more complicated. Given this background, a method of reliability evaluation for the active distribution network considering ‘supply-grid-load’ is proposed. On the supply side, a distribution network islanding model considering DG is established, with the objective of supplying power to the maximised amount of equivalent power load. On the grid side, the influence of distribution network automation on the distribution network reliability is elaborately analysed and the time-varying failure rate model of equipment which considers the life cycle characteristics is presented. On the load side, an incentive-based FL model is proposed based on the elastic coefficient matrix. Finally, simulation results of RBTS-BUS6 system demonstrate the effectiveness of the proposed model and method.

Ascorbic acid (AA) is an esstential micronutrient in the human body and participates in vital processes. It can only be supplemented by external intake, making the determination of AA in food or beverages of significance. In the present work, MnO2 nanoparticle (MnO2 NP) based turn-off colorimetry was established for AA determination on the basis of AA-stimulated inhibition of catalytic oxidation. MnO2 NPs were synthesized through a biotemplating method and displayed effective catalytic oxidation activity for oxidation of TMB, triggering a chromogenic reaction. Interestingly, the introduction of AA induced the decomposition of MnO2 NPs and as a consequence decreased the colour. Therefore, sensitive and selective turn-off colorimetry for AA detection was established and a satisfactory linear range of 0.5–30 μM with a detection limit of 0.28 μM was obtained. This MnO2 NP-based method was activated via a novel sensing principle, complementing and facilitating colorimetry for AA.

Antimony is one of the heavier pnictogens and is widely found in human food chains, water sources, and as an air pollutant. Recent years have seen steadily increasing concentrations of antimony in the ecological environment; critically, several studies have indicated that antimony might pose a tumorigenic risk factor in several cancers. Therefore, antimony toxicity has attracted increasing research attention, with the molecular mechanisms underlying suspected antimony-mediated tumor transformation of greatest interest. Our results showed that the serum concentration of antimony was higher in bladder tumor patients relative to levels in non-tumor patients. Moreover, that such high antimony serum concentration were closely associated with poorer outcome in bladder tumor patients. Additionally, we demonstrated that the presence of antimony promoted both in vitro and in vivo bladder tumor cell growth. Our results also indicated that low-dose antimony resulted in significantly decreased mitochondrial membrane potential, mitochondrial respiratory enzyme complex I/II/III/IV activity, ATP/ADP ratio, and ATP concentration relative to the control group. These findings suggested that antimony caused mitochondrial damage. Finally, we found that low-dose antimony(0.8uM) inhibited mitophagy by deregulating expression of PINK1, Parkin, and p(ser65)-Parkin, and activation of PINK1-Parkin pathway by CCCP could inhibit antimony-induced tumor cell growth. Collectively, this inhibited the proliferation of bladder tumor cells. Overall, our study suggested that antimony promoted bladder tumor cell growth by inhibiting PINK1-Parkin-mediated mitophagy. These findings highlight the therapeutic potential in targeting molecules within this antimony induced-PINK1/Parkin signaling pathway and may offer a new approach for the treatment of bladder cancer.

Urban growth does not always strictly follow historical trends; the government may reshape urban growth patterns with considerations of ecological conservation or other plans. Both urban dynamic rules and landscape characteristics are the two main factors influencing the spatial patterns of cities, and obtaining an optimized spatial pattern is very important for sustainable urban growth. Therefore, in this study, we integrated logistic regression (LR) with the ant colony optimization (ACO) model to analyze the optimal scenario for smart urban growth. The LR model was used to discuss the relationship between urban patterns and environmental variables such as topography, development centers, and traffic conditions. Then, the urban growth probability was generated using the parameters obtained from LR. The ACO model was further integrated to optimize urban land allocation, which can meet the requirement of high growth probability, and a connected and compacted landscape pattern. This can solve the problem of urban land only being allocated by LR from being distributed fragmentarily in the space. With this integrated model, Guangzhou City, a rapidly developing area in China, was selected as a case study. The urban patterns derived from LR, as well as a simulation scenario using logistic regression-based cellular automata (LR-CA), were used in the comparison. Six landscape metrics were chosen to validate the performance of this proposed model at the pattern level. The results show that the LR-ACO model has a better performance in urban land allocation. This study demonstrated that models that couple dynamic rules and planning objectives can provide plausible scenarios for smart urban growth planning.

Mangroves serve many important ecological functions and consequently represent a dominant coastal ecosystem. However, coastal regions are very susceptible to ecological damage due to their high population density, urban expansion being one of the most important influencing factors. Accordingly, it is vital to ascertain how urban expansion endangers mangrove ecosystems. This study used the decision-tree classification method based on classification and regression tree (CART) algorithm to extract areas of mangrove and built-up land from Landsat images. A correlation analysis was performed between the change in the area of mangroves and the change in the area of built-up land at the cell scale. This study aimed to reveal the magnitude of the influence of urban expansion on mangrove forests in different periods and in different regions, and to identify the places that are seriously affected by urban expansion. The results demonstrate that this approach can be used to quantitatively analyze the impact of urban expansion on mangrove forests, and show that larger areas of mangrove were affected by urban expansion in the past 30 years. The effects of urban expansion were stronger over time, with approximately 12% of cells containing mangroves showing a negative correlation between the increase in the area of built-up land and the change in the area of mangrove forests to different degrees from 2005 to 2015. The same quantitative analysis was also carried out in three subregions of Guangdong Province, namely western Guangdong Province, the Pearl River Delta, and eastern Guangdong Province. It was found that the situations in these three regions were very different due to discrepancies in the distribution of mangroves, the rate of urban expansion, and the awareness of the local government regarding environmental protection. These results can assist in the management of coastal cities and the protection of mangrove ecosystems.

Taking advantage of the compelling properties of d-penicillamine (d-PA) combined with copper, a method for the sensitive and selective determination of d-PA was established using copper nanocluster (Cu NC)-based fluorescence enhancement. d-PA molecules containing a thiol compound showed a strong tendency to combine with the surface of Cu NCs, causing the re-dispersion of nanoclusters and therefore fluorescence intensity was enhanced. Fluorescence enhancement efficiency of Cu NCs induced by d-PA was linear, with the d-PA concentration varying from 0.6-30 μg ml-1 (R2 = 0.9952) and with a detection limit of 0.54 μg ml-1 . d-PA content in human urine samples was detected with recoveries of 104.8-112.99%. Fluorescence-enhanced determination of d-PA using Cu NCs was established for the first time and this rapid, easy and sensitive method should attract much attention for this application.

The oxidation behavior of Ti3AlC2-20TiB2 composite was studied at 500 °C–900 °C in air. The composite showed a very low oxidation rate and followed a logarithmic oxidation law. The in-situ incorporation of TiB2 suppressed the anomalous rapid oxidation of the substrate Ti3AlC2 occurred near 600 °C by forming a protective B2O3 glass layer, and also improved the oxidation resistance of the MAX phase at intermediate-temperature.

Taking advantages of reticular proteins and reductive groups on the surface, eggshell membrane (ESM) was selected to synthesize MnO2 nanoparticles from potassium permanganate through a super simple way in which ESM acted as both template and reductant. This process avoided harsh reaction conditions or complicated aftertreatments and thus owned the merits of green synthesis, handy operation, low cost, and easy purification. The ESM-templated MnO2 nanoparticles (MnO2 NPs/ESM) were characterized, and the content of nanomaterials on the template was tested. MnO2 NPs/ESM showed a good capacity for decontamination of tetracycline hydrochloride (TCH). The macroscopical materials can be separated easily by taking the membrane out to stop the degradation instead of centrifugation or filtration. It was studied that 72.27% of TCH (50 mg/L) was decontaminated in 20 min by 0.1920 g/L MnO2 nanoparticles, and removal efficiency could reach 83.10% after 60 min under buffered condition. The kinetics was studied with or without buffer, and it was concluded that the degradation process followed a pseudo-second-order model. The facile synthesis of materials and effective degradation would facilitate the nano-MnO2-based decontamination applications.

Typhoons can affect various hydrodynamic processes, such as upwelling, vertical mixing, and entrainment, which in turn influence the growth and redistribution of phytoplankton. In this study, responses of phytoplankton to consecutive typhoons Barijat and Mangkhut in summer 2018 in the northern South China Sea (NSCS) were investigated through combining remote sensing, numerical simulation, and Argo profile data. Variations of physical and biological properties induced by Barijat and Mangkhut over the study region were observed. Regional chlorophyll-a (Chla) algorithms over the NSCS were assessed in order to accurately quantify typhoon-induced variations of phytoplankton. Chla concentration decreased slightly over the region of interest after the passage of Barijiat while increased obviously after the passage of Mangkhut. Satellite-derived Chla increased by ~63% on average after the consecutive typhoons. Responses of phytoplankton size structure (PSS) were further investigated over the continental shelf and the deep ocean in the NSCS. For the continental shelf, the increment of micro- and nano-phytoplankton was about 1.5-fold as high as that of pico-phytoplankton, compared with a 0.5-fold increment for the deep ocean. This study attested the discrepant responses of different phytoplankton size classes to typhoons. It was of great significance to expand our understanding of ocean physical and ecological responses to extreme phenomena. Our finding underscores the potential of remote sensing to investigate typhoon-induced variation of PSS and could be the key to accurately assess typhoon-induced carbon fluxes, primary production, and potential fishing ground in the future.

Eggshell membrane (ESM) is selected as biotemplate to prepare MnO2 submicroparticles (SMPs) using Chinese Brush with sodium hydroxide solution. The size with average 710 nm of the obtained materials is in good consistency with the microsructured biotemplate. An efficient and convenient absorbent for methylene blue (MB) is developed. The removal efficiency could reach up to 93% in 35 min under room temperature without pH adjusting owing to the excellent adsorption from ESM itself and hydroxyl group formed on the surface of MnO2 crystal in the aqueous solution. Materials on the membrane can be separated from the wastewater simply to avoid the secondary pollution caused by the leak of material. This interesting approach to MnO2 SMPs and facile operation for MB adsorption could open a new path to the submicro-materials based wastewater treatment.

The effectiveness of vertical baffles of different configurations in suppressing violent transient sloshing was numerically investigated with the lattice Boltzmann method (LBM). Volume-of-fluid (VOF) and large eddy simulation (LES) models were employed to simulate a violent wave-breaking phenomenon at finite water depths under resonance conditions. The liquid elevation, total impact pressure and energy dissipation were measured to evaluate the damping effect with regard to the installation of single or double vertical baffles of different heights and separation distances. The results indicate that the interaction between the free surface and the vortex caused by the shearing effect at the tip of vertical baffles constitutes the essential mechanism responsible for damping the sloshing wave. A quantitative method is first proposed to distinctively quantify the viscous dissipation that occurred on the interface and interior of the fluid, and the results demonstrate that strong internal dissipation is most important for suppressing the sloshing wave. The spacing distance is important for the damping effect on the sloshing pressure, and the proper distribution of two vertical baffles can inhibit the peak impact pressure to more than about three times lower than that when double baffles with a poor arrangement are used.

Taking consideration of metal-induced fluorescence quenching and excellent coordination effect of D-penicillamine (D-PA), a graphene quantum dots (GQDs)-based fluorescent switch for D-PA detection was designed and established firstly with the help of lead ions. GQDs obtained from citric acids made them rich in carboxyl and hydroxyl groups, giving GQDs the ability to combine with lead ions. As anticipated, the fluorescence intensity was quenched by Pb2+ through electron transfer process. Further, the addition of D-PA effectively recovered the fluorescence due to the departure of Pb2+ from GQDs aroused by the strong coordination between D-PA and Pb2+. Thus, a fluorescent switch was activated for D-PA detection. The fluorescence recovery efficiencies were found to be proportional to the concentration of D-PA in the range of 0.6–50 μmol L−1 and the detection limit was 0.47 μmol L−1. The real sample detection was performed in human urea sample and satisfactory recoveries of 96.84%–102.13% were obtained. The GQDs-Pb2+ based fluorescent switch sensing method was firstly established with low detection limit and wide linear range, making it a supplement and improvement for D-PA detection.

The Pearl River Estuary (PRE) is a window into the drastic changes that occurred throughout coastal areas due to artificial agglomeration following China’s 1978 economic reform. In this study, multi-temporal Landsat remote sensing images were used to extract coastlines in the PRE with the support vector machine (SVM). In addition, the coastline was divided into nine segments by using the eight mouths as the cut-off points. A statistical analysis was performed on the length and changes of each coastline segment. The analysis was focused on the five shores that exhibited obvious changes. Subsequently, a correlation analysis between three artificial development factors, namely, the development intensity, development speed, and development density, and the shoreline length was conducted, following which the main driving factors influencing the changes in the coastline were obtained. Finally, the dynamic processes and artificial mechanisms of the coastline changes in the PRE were deeply analyzed. The results reveal that the coastline has been gradually advancing over a distance of 164.01 km toward the sea over the past 40 years, and the growth rate initially showed a rapidly increasing trend in 1978 but has since slowed from 1998 to the present. The most significant changes were detected along the Hutiao Men–Jiti Men and Jiti Men–Modao Men shore areas due to the impacts of human activities. The development speed presented dominant influence on coastline change at the end of the 20th century, but the development intensity was the primary influence factor during the early 21st century. To a certain extent, the monitoring and analysis of historical coastline changes can contribute to coastal zone planning in more detail, thereby promoting the sustainable development of coastal zones.

InAlN/GaN high-electron mobility transistors (HEMTs) with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/Al/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF characteristics of the devices were measured. The fabricated devices show a maximum drain current density of 2.18 A/mm at VGS = 2 V, a low on-resistance (Ron) of 1.49 ωmm and low gate leakage current. An excellent frequency response was also obtained. The current cut-off frequency (fT) is 81 GHz and the maximum oscillation frequency is 138 GHz, respectively.