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NIR-activated therapies based on light-responsive drug delivery systems are emerging as a remote-controlled method for cancer precise therapy. In this work, fluorescent dye indocyanine green (ICG)-conjugated and bioactive compound gambogic acid (GA)-loaded polymeric micelles (GA@PEG-TK-ICG PMs) were smoothly fabricated via the self-assembly of the reactive oxygen species (ROS)-responsive thioketal (TK)-linked amphiphilic polymer poly(ethyleneglycol)-thioketal-(indocyanine green) (PEG-TK-ICG). The resultant micelles demonstrated increased resistance to photobleaching, enhanced photothermal conversion efficiency, NIR-controlled drug release behavior, preferable biocompatibility, and excellent tumor accumulation performance. Moreover, upon an 808 nm laser irradiation, the micellar photoactive chromophore ICG converted the absorbed optical energy to both hyperthermia for photothermal therapy (PTT) and ROS as the feedback trigger to the micelles for the tumor-specific release of GA, which could serve as not only a chemotherapeutic drug to directly kill tumor cells but also a heat shock protein 90 (HSP90) inhibitor to realize the photothermal sensitization. As a result, an extremely high tumor inhibition rate (97.9%) of mouse 4 T1 breast cancer models was achieved with negligible side effects after the chemo-photothermal synergistic therapy. This NIR-activated nanosystem with photothermal self-sensitization function may provide a feasible option for the effective treatment of aggressive breast cancers.

The pantograph–catenary system is crucial to the transmission of electrical power from catenary lines to electrified trains. The occurrence of arcs could damage or interrupt railway operations. We propose a CNN-based model to detect arcs and recognize their magnitudes. First, we decompose the pantograph videos recorded by a camera fixed on China High-Speed train into continuous frames, and grayscale-process and segment those images to obtain an arc image set. Then, we divide the image set into training samples and test samples. And the training samples are further divided into three classifications labeled as 0, 1, 2, which are used to train CNN model. The accuracy of CNN trained result reaches 0.95, and the loss function converges to 0.083. Second, we use the trained network to detect arcs in the images of the test samples, and convert arc detection results to a time series of arc scores. Thus the occurrence of arcs and their magnitudes can be determined. Finally, we conduct experiments to compare our approach with other models. The results demonstrate the approach's high accuracy, robustness, and high speed, when dealing with images taken from unstable surroundings. It could be applied to other EMU models or environments with adjusted parameters.

A multi-functional NiMo-ceria-zirconia composite was developed as an anode for a solid oxide fuel cell (SOFC) running on isooctane, a commonly used gasoline surrogate. The anode layer was fabricated on an electrolyte-supported single cell using yttria-stabilized zirconia (YSZ) as the electrolyte and La0.6Sr0.4Co0.2Fe0.8O3-δ as the cathode. Our results indicate that the single NiMo-ceria-zirconia layer possesses a dual-functionality: firstly to internally convert complex hydrocarbons into synthesis gas with a high resistance to coking and secondly to electrochemically oxidize the synthesis gas mixture for electric power generation. Compared with the conventional Ni-YSZ anode single cell, the application of the ceria-zirconia in the anode significantly suppresses carbon deposition and improves the performance stability of the single cell. Furthermore, the addition of Mo in the Ni-ceria-zirconia appears to facilitate a higher degree of sintering for the anode, which increases the electronic conductivity and maximum power density of the single cell. Consequently, at 800 °C the single cell with 5 wt.% Mo in the Ni-ceria-zirconia-based anode displayed a higher maximum power density of 212 mW cm−2 at 0.48 V and significantly enhanced performance stability than the conventional Ni-YSZ anode single cell in the isooctane/air operating mode.

This paper describes an application of a NiMo-ceria-zirconia (NiMo-CZ) catalyst as a micro-reforming layer for solid oxide fuel cells running on isooctane (i.e., a gasoline surrogate). The catalyst layer was applied on top of a conventional anode supported single cell with a configuration of Ni-yttria-stabilized zirconia (YSZ) anode, YSZ/Ce0.8Sm0.2O1.9 bi-layer electrolyte and La0.6Sr0.4Co0.2Fe0.8O3-δ cathode. Our findings show that the application of the novel catalyst layer was an effective way to reform the mixture of isooctane and air into H2 and CO, which facilitated the electrochemical oxidation of complex hydrocarbons at the anode. At 750 °C, the single cell with the micro-reforming layer exhibited a low polarization resistance of 1.36 Ω cm2 and a maximum power density of 405 mW cm−2 in the direct feeding condition of an isooctane/air mixture. At the current density of 500 mA cm−2, the cell voltage presented a fairly low degradation rate of 3.0 mV h−1 during a 12 h stability test. The excellent electrochemical performance suggests the high catalytic activity of the NiMo-CZ catalyst layer for reforming isooctane and suppressing degradation of the single cell in the direct feeding of isooctane/air.

Loess deposits are important archives of past climate change in subtropical China, where long-term terrestrial records are scarce. However, only a few long-term records with reliable dating were reported in Jiangsu Province, where loess deposits in southeastern China were first discovered and designated as the Xiashu Loess. Moreover, the provenance of the Xiashu Loess is still controversial. This study presents the magnetostratigraphy and detrital zircon U–Pb age results of loess deposits at Zhoujiashan in Nanjing, Jiangsu Province. To date, this section (with basal age of approximately 0.88 Ma) may be the oldest loess deposits discovered in southeastern China. Based on the detrital zircon U–Pb ages of the Zhoujiashan section, together with published results of geochemistry, geomorphology, sedimentology, and meteorology, we propose that the Xiashu Loess has two mixed sources. Local materials derived from the Yangtze River Basin (including exposed river/lake beds, floodplains, and mountains) served as a major contributor. The distal eolian dust that originated from the arid areas of North China (including deserts, piedmont alluvial fans, and drylands) played a minor role in the formation process of the Xiashu Loess. The nearly synchronous onset age (approximately 0.88–0.85 Ma) of the Xiashu Loess was attributed to a regional environmental event during the middle Pleistocene transition.

Catalytic reduction by the reverse water gas shift (RWGS) reaction is an efficient way to utilize carbon dioxide and reduce its environmental impact as a greenhouse gas. In this research, an active CuFe/Al 2 O 3 nano powder was developed as a high temperature reforming catalyst for the RWGS reaction. The powder was synthesized by a wet-impregnation method and the copper alloy was uniformly dispersed on the γ-Al 2 O 3 support. At a gas space velocity of 60,000 h −1 , the conversion of carbon dioxide was 42% at 700 °C, which is very close to the equilibrium conversion of 44%. The results indicated excellent reforming activity of the CuFe/Al 2 O 3 catalyst for the high temperature RWGS reaction. In addition, the catalyst was applied in the form of a reforming layer over a conventional Ni-based electrode of a solid oxide electrolysis cell (SOEC) for an integrated SOEC-RWGS system. Hydrogen produced from steam electrolysis over the Ni-based cathode can be efficiently utilized to reduce the carbon dioxide by the RWGS reaction over the CuFe/Al 2 O 3 -based reforming layer. In this bilayer design, the reforming layer maintained the high surface area necessary for achieving good reforming activity, while the electrode layer possessed a high degree of sintering to enhance its electrochemical function. A high conversion of carbon dioxide (37% at 700 °C) was obtained in our bilayer SOEC-RWGS system. This promising result suggests the feasibility of the integrated SOEC-RWGS system for an efficient co-electrolysis device.

A titanium-doped Ce 0.8 Sm 0.2 O 1.9 composite is developed as an anode component of low temperature solid oxide fuel cells running on methane fuel. Crystallographic parameters of (Ce 0.8-x Ti x )Sm 0.2 O 2-δ (0.00 0.8-x Ti x )Sm 0.2 O 2-δ composites are applied to an anode-supported single cell consisting of Ni-(Ce 0.8-x Ti x )Sm 0.2 O 2-δ anode/Ce 0.8 Sm 0.2 O 1.9 electrolyte/La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ cathode. Catalytic properties of Ni-(Ce 0.8-x Ti x )Sm 0.2 O 2-δ are inspected with the electrochemical performance and performance stability of the cells in dry methane fuel. The cell with Ni-(Ce 0.73 Ti 0.07 )Sm 0.2 O 2-δ (x = 0.07) anode displays a low polarization resistance and an optimum maximum power density (679 mW cm −2 at 600 °C). A performance stability investigation indicates that the cell exhibits a fairly low degradation rate of 3 mV h −1 during a 31 h operation in dry methane. These findings suggest the application potential of the titanium doped Ce 0.8 Sm 0.2 O 1.9 for the anode of solid oxide fuel cells.

This short communication describes a novel MoO2-based cathode and its potential application for solid oxide electrolysis cells. Electrochemical performances of the MoO2-based cathode are investigated with respect to a commercial Ni/YSZ-based cathode for both co-electrolysis (of H2O and CO2) and electrolysis of only CO2 at 750 °C. Under the co-electrolysis mode, the MoO2-based cell and the Ni/YSZ cell show a similar electrochemical performance, while in the CO2 electrolysis mode, the MoO2-based cell demonstrates a much improved electrocatalytic activity compared with the Ni/YSZ cell. This improved electrochemical activity of the MoO2-based cathode under the CO2 electrolysis mode is further investigated by its electrochemical impedance spectroscopy (EIS) study. According to our EIS study, the polarization resistance of the MoO2-based cell is 67% lower than that of the Ni/YSZ-based cell under the open circuit potential. A performance stability study indicates that the MoO2-based cell exhibits a relatively low performance degradation under the CO2 electrolysis mode during its 10-h constant voltage test, and low carbon amount (6.6 wt.%) is detected after the performance stability measurement. These findings suggest the advantages of applying the MoO2-based cathode for the CO2 electrolysis.

Electricity is the most commonly used form of energy for artificial lighting in modern society. Despite a rapid growth in the rate of electrification, 9% of electrified Indian households in our six sampled states continued to use kerosene as their primary lighting fuel in 2018. This appears as a puzzle considering the benefits of electric lights. Using a panel survey of rural households in six states in India, we examine why some grid-connected households primarily used kerosene lamps for illumination. We use a logistic regression model to test our hypothesis regarding the relationship between primary lighting choices and electricity quality. The results show that household primary lighting choices are correlated with nighttime duration of electricity service, daytime duration of electricity service, and the number of days without any electricity connection, at the 99% confidence level. Among these three factors, nighttime duration of electricity service has the greatest impact. To further promote the use of electric lights, intensive schemes to improve electricity quality are needed.

This short communication describes the performance of a solid oxide fuel cell (SOFC) fueled by directly feeding premium gasoline to the anode without using external reforming. The novel component of the fuel cell that enables such operation is the mixed conductivity of MoO 2 -based anode. Using this anode, a fuel cell demonstrating a maximum power density of 31 mW/cm 2 at 0.45 V was successfully fabricated. Over a 24 h period of operation, the open cell voltage remained stable at ∼0.92 V. Scanning electron microscopy (SEM) examination of the anode surface pre- and post-testing showed no evidence of coking.

A NiMo–Ce0.5Zr0.5O2-δ (NiMo-CZ) catalyst has been developed for gasoline-fed solid oxide fuel cells (SOFCs). To apply the catalyst on a button-type single cell, the NiMo-CZ is deposited on top of conventional Ni-yttria-stabilized zirconia (YSZ) anode as a catalytic internal micro-reforming layer. The NiMo-CZ layer is effective in increasing the gasoline conversion and enhancing the yields of both H2 and CO at 750 °C. On the other hand, due to the high mechanical stress induced from the constrained sintering with a thicker catalyst layer, only a limited amount of catalyst (~20 mg) could be applied over the conventional button-type cell, which is not beneficial for enhancing overall cell performances. To overcome this issue, a tubular single cell configuration is adopted that allowed for higher catalyst loadings. By introducing higher catalyst loadings (~80 mg) in the vacant tubular channel of the single cell, the gasoline conversion, H2 yield, and CO yield all improve while cell lifetime increases by 42% compared to the performance of the button-type cell. The results suggest the potential of the NiMo-CZ catalyst for gasoline-fed SOFCs, and it demonstrates the advantage of the tubular single cell configuration for incorporating higher catalyst loadings for internal catalytic fuel reforming.