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The encapsulation of CsPbBr3 nanocrystals (NCs) in oxide glass can effectively avoid contact of the external environment with the halide perovskite. However, the effects of hydroxyl and oxygen on NCs cannot be completely excluded because of the nature of oxide glass itself. Here, we proposed a new solution to solve these problems by using fluorophosphate (FP) glass as the embedding matrix. The composition (Br concentration) and heat treatment conditions (temperature and time) of the glass matrix were designed and optimized to improve the optical properties of CsPbBr3 NCs. The results showed that highly pure green light with an emission peak of 534 nm and a full-width at half-maximum (FWHM) of approximately 19 nm was achieved using CsPbBr3 NCs@glass and a light-emitting diode (LED)/laser diode (LD). The Commission Internationale de l'Eclairage (CIE) coordinates of the two devices were (0.243, 0.723) and (0.239, 0.739), with very high color purities of 96.6% and 97.3%, respectively. The photoluminescence quantum yields (PLQYs) of the samples excited at 365 nm and 450 nm wavelengths were 34.54% and 38.85%, respectively. Additionally, the chemical stability of CsPbBr3 NCs was significantly improved by the encapsulation in FP glass, retaining 88% of the original PL intensity after 30 days of storage in deionized water. This work provides a new choice to improve the stability of a halide perovskite in a matrix. [ABSTRACT FROM AUTHOR]

The development of a current collector for Li-ion batteries is of great significance for improving the performance of Li-ion batteries. Tensile property and corrosion performance of the positive electrode current collectors are an indispensable prerequisite for the realization of high-performance Li-ion batteries. In our study, the effects of Ag alloying on the microscopic structure, electrical conductivity, tensile property and corrosion resistance of Al-xCu (x = 0.1–0.15%) alloy foils were investigated. Moderate Ag addition on the Al-Cu alloy could reduce the size of second phases and promote the formation of second phases. The tensile strength of the Al-0.1Cu-0.1Ag alloy was higher than that of the Al-0.1Cu alloy at both room and high temperatures. All of the alloy foils demonstrated high electrical conductivity around 58% ICAS. The corrosion potential and corrosion current density of the Al-0.1Cu alloy were demonstrated by Tafel polarization to be −873 mV and 37.12 μA/cm2, respectively. However, the Al-0.1Cu-0.1Ag alloy showed enhanced corrosion resistance after the Ag element was added to the Al-0.1Cu alloy, and the Al-0.1Cu-0.1Ag alloy had a greater positive corrosion potential of −721 mV and a lower corrosion current density of 1.52 μA/cm2, which suggests that the Ag element could significantly improve the corrosion resistance of the Al-Cu alloy. [ABSTRACT FROM AUTHOR]

On the basis of reprocessing 34 new two‐dimensional spliced long sections (20,191 km) in the Tarim Basin, the deep structure features of the Tarim Basin were analyzed through interpreting 30,451 km of two‐dimensional seismic data and compiling basic maps. Seismic interpretation and geological analysis conclude that the Nanhua‐Sinian strata are a set of rift‐depression depositional systems according to their tectonic and depositional features. The rift valley formed in the Nanhua Period, and the transformation became weaker during the late Sinian Period, which eventually turned into depression. From bottom to top, the deposited strata include mafic igneous, tillite, mudstone, and dolomite. Three major depocenters developed inside this basin during the rift stage and are distributed in the eastern Tarim Basin, the Awati area, and the southwestern Tarim Basin. Among them, the rift in the eastern Tarim Basin strikes in the near east‐west direction on the plane and coincides with the aeromagnetic anomaly belt. This represents a strong magnetic zone formed by upwelling basic volcanic rock along high, steep normal faults of the Nanhua Period. Controlled by the tectonic background, two types of sedimentary systems were developed in the rift stage and depression stage, showing two types of sequence features in the Sinian depositional stage. The Nanhua System appears as a wedge‐shaped formation, with its bottom in unconformable contact with the base. The rifting event has a strong influence on the current tectonic units in the Tarim Basin, and affects the distribution of source rock in the Yuertus Formation and reservoir beds in the Xiaoerbulake Formation in Lower Cambrian, as well as the gypseous cap rock in Middle Cambrian. The distribution features of the rifts have important and realistic significance for determining the direction of oil and gas exploration in the deep strata of the Tarim Basin. Comprehensive analysis suggests that the Tazhong region is the most favorable zone, and the Kalpin‐Bachu region is the optimal potential zone for exploring sub‐salt oil and gas in deep Cambrian strata. [ABSTRACT FROM AUTHOR]

A large quantity of drilling core, paleontology, geochemistry and geophysics data revealed several features of the Jiyang subbasin during the deposition of the Ek1-Es4x members: (1) the paleotopography of the gentle slope belt had an extremely low gradient; (2) the paleoclimate frequently alternated between dry and wet periods in a generally arid setting; (3) there was strong weathering around the periphery of the basin; (4) the lake was very shallow; (5) the lake level frequently rose and fell; and (6) the sedimentary environment of the gentle slope belt was an over-flooding lake. All of these factors provided favorable geological conditions for the development of an over-flooding lake delta. The lithologies of the continental over-flooding lake delta deposits are complex and diverse. The compositional maturity is moderate to low, and the grain size distribution curves and sedimentary structures indicate the presence of both gravity and traction currents. The sedimentary microfacies associations consist of a combination of ordered superposition of flood channels, distributary channels and sheet sands. The delta exhibits a weak foreset seismic reflection. The over-flooding lake delta deposits are laterally extensive. The sandstone content is high, and the individual sandstone beds are thin. The flood channel and distributary channel deposits exhibit evidence of bifurcation and lateral migration. The distribution of the sandbodies and the oxidation color of the mudstones provide evidence of cyclic deposition. The paleoclimate was the dominant factor controlling the development of the over-flooding lake delta. Due to the frequently alternating wet and dry paleoclimates, the over-flooding lake delta is characterized by the development of a broad upper plain and a lower delta plain. The upper delta plain is characterized by flood channel deposits, whereas the lower delta plain is represented by distributary channel deposits. The transition zone is characterized by the interaction of flood channels and distributary channels. Due to fault activity, the sandbodies of the over-flooding lake delta were juxtaposed against hydrocarbon source rocks, which was favorable for the development of lithologic reservoirs or structural-lithologic reservoirs. The lower delta plain deposits comprise the most favorable reservoirs. [ABSTRACT FROM AUTHOR]

The Boxing Sag is located in the southwest of Dongying Depression, southern Bohai Bay Basin of East China. It is one of the main petroliferous sags in the Dongying Depression, and has two major source rocks, namely the upper 4th Member (E s4u) and lower 3rd Member (E s3l) shales of Eocene Shahejie Formation, which are the new exploration targets in recent years. In this study, 16 core samples were collected from E s4u and E s3l shales in the Boxing Sag, and the saturate hydrocarbons were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), respectively. The results show that E s4u shale has obvious phytane and gammacerane predominance, higher concentration of tricyclic terpanes and regular steranes, and very low concentration of 4-methly steranes; E s3l shale has pristane predominance, lower concentration of tricyclic terpanes, gammacerane and regular steranes, and higher concentration of 4-methly steranes. The E s4u shale can be further divided into two types based on the distribution of n-alkanes in gas chromatograms: normal distribution and double peak pattern. The biomarker characteristics and sedimentary facies distribution show that E s4u shale was deposited in the saline-hypersaline semi-deep (Type A E s4u shale, sag center) to shallow (Type B E s4u shale, sag edge) lacustrine environments, E s3l shale was deposited in the freshwater-brackish semi-deep-deep lacustrine environments, and the former sedimentary facies maps of E s4u and E s3l in the Boxing Sag are further modified. [ABSTRACT FROM AUTHOR]

The increasing application of lithium-ion batteries has led to higher requirements being imposed on the performance of current collectors. In this work, the effect of La content on the microstructure and properties of Al-0.2Fe-0.06Cu alloy was invested through optical microscopy, scanning electron microscopy and mechanical/electrical/electrochemical performance tests. Experimental results indicated that the addition of La was beneficial to grain refinement and promote the formation of La-containing compounds. However, excessive La addition weakened the refinement effect. Grain refinement played a major role in affecting the mechanical properties of the alloy, but had little effect on the conductivity. In comparison with Al-0.2Fe-0.06Cu, the La-containing alloys had lower corrosion potential, which indicated that the addition of La element could improve the corrosion resistance of the Al-0.2Fe-0.06Cu alloy. The addition of La improved the mechanical properties of the alloy at room temperature and 50 °C. When the La addition was 0.1wt.%, the alloy had the best mechanical properties. The corrosion resistance of the alloy continued to improve with increases in the La content. [ABSTRACT FROM AUTHOR]

Al–xFe–Si–La alloys (x = 0.07, 0.2, 0.4 wt. %) were designed as current collectors of positive electrodes in lithium ion batteries, and the microstructure, tensile strength, electrical conductivity and corrosion resistance of the alloys were investigated with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), a tensile test, an electrical conductivity test, and an electrochemical test. It was found that the amount of Fe content greatly affected the quantity of the second phases in the alloys. The higher the Fe content was, the more the second phases were. With increase of the Fe content, the tensile strength and corrosion resistance of the Al–xFe–Si–La alloys were improved, and the electrical conductivity of the Al–xFe–Si–La alloys could meet the application requirements. Compared to the Al–0.07Fe–0.1Si–0.07La alloy, the strength of the Al–0.4Fe–0.1Si–0.07La alloy was greatly enhanced. The Al–0.4Fe–0.1Si–0.07La alloy also had a higher corrosion potential than that of the Al–0.07Fe–0.1Si–0.07La alloy. [ABSTRACT FROM AUTHOR]

The increasing demand for high-performance current collectors of lithium ion secondary batteries requires that the employed aluminum alloys have better mechanical properties and superior electrochemical performance. The effect of Si addition on the microstructure, tensile and electrochemical performance of Al-Fe-Cu-La alloy was investigated by optical microscopy, X-ray diffraction, scanning electron microscopy, a tensile test, conductivity test and Tafel polarization curve test. Experimental results indicated that Si addition to the Al-Fe-Cu-La alloy helped to refine the longitudinal grain size of the alloy. The Si-containing phase (AlFeSi) nucleated and grew along the surface of the AlFeLa phase. The Si addition to the Al-Fe-Cu-La alloy could greatly increase the tensile strength in the temperature range of −20 °C to 50 °C and improve high temperature stability of the alloy. Also, the addition of Si promoted the formation of the AlFeSi ternary phase, which helped to improve the corrosion resistance of the alloy. [ABSTRACT FROM AUTHOR]

Al-xFe-La alloys (x = 0.07, 0.1, 0.2) for aluminum current collectors of lithium-ion batteries were prepared and the microstructure of Al-0.07Fe-0.07La, Al-0.1Fe-0.07La and Al-0.2Fe-0.07La aluminum alloys were observed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS). The experimental results showed that with the increase of Fe content, the size of the second phases in Al-xFe-0.07La alloys became finer and more dispersed and that the microstructure of the alloy had improved. The strength and corrosion resistance of Al-xFe-La alloys were studied by tensile tests and electrochemical tests and the morphological investigations of samples were also conducted by SEM and EDS. With the increase of Fe content, the strength and corrosion resistance of Al-xFe-La alloys became better. Compared to Al-0.07Fe-0.07La alloy, the yield strength and tensile strength of the Al-0.2Fe-0.07La alloy increased by 51.19% and 58.48% respectively, and the elongation increased by 88.41%. Moreover, Al-0.2Fe-0.07La alloy had much more positive corrosion potential and much smaller corrosion current than those of Al-0.07Fe-0.07La alloy. [ABSTRACT FROM AUTHOR]

Al foil with high formability and corrosion resistance is highly desired for lithium-ion battery soft packaging. Annealing treatment has a significant impact on the performance of soft packaging Al foil. The effects of both La content and the annealing temperature on the microstructure, mechanical properties, and corrosion behavior of Al-1.5Fe-La alloy was investigated through optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), tensile testing, potentiodynamic polarization testing, and electrochemical impedance spectroscopy (EIS) testing. A higher addition of La resulted in the formation of AlFeLa particles and a refinement of the Fe-rich second phase. The Al-1.5Fe-0.25La alloy had a higher formability and corrosion resistance than the Al-1.5Fe-0.1La alloy. Microstructure analysis indicated that recovery, recrystallization, and grain growth successively occurred in the Al-Fe-La alloy with the increase of the annealing temperature from 200 °C to 250 and 380 °C. After annealing at 250 °C, the Al-Fe-La alloys had the highest corrosion resistance due to refined grain and a high fraction of small-angle grain boundaries. [ABSTRACT FROM AUTHOR]

Effect of Ce addition on the microstructures, mechanical properties and electrochemical properties of Al-Cu-Mn-Mg-Fe lithium battery alloy was investigated by optical microscope (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), tensile testing and electrochemical testing. Experimental results indicate that Ce addition resulted in the formation of Al 8 Cu 4 Ce phase in the Al-Cu-Mn-Mg-Fe alloy. The Ce-containing precipitates nucleated and grew up along the surface of Al 6 (Mn, Fe) precipitates. Al 6 (Mn, Fe) precipitates could be remarkably refined by Ce alloying. The aging precipitation behavior of Sˈ phases could be promoted after Ce addition to the alloy. In comparison with Ce-free alloy, the Ce-containing alloy had higher tensile strength at both low temperature and elevated temperature. Especially at 200 °C, the yield strength and tensile strength of Ce-containing alloy substantially increased by 23.4% and 27.08%, respectively. Potentiodynamic polarization testing indicated that the Ce-containing alloy had a more positive corrosion potential and a lower corrosion current density. [ABSTRACT FROM AUTHOR]

Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al 8 Cu 4 Ce phase and many Al 20 Cu 2 Mn 3 particles could be found. In addition, the precipitation of conventionally dominant phase of Al 2 Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance. [ABSTRACT FROM AUTHOR]

As an effective method to improve the sensitivity of detection, spectral conversion technology has been widely used in solar-blind ultraviolet communication (UVC). However, producing a spectral converter with high efficiency, short decay lifetime, and excellent stability in the field of UVC detection remains an outstanding challenge. In this Letter, a kind of ${{\rm Sn}^{2 + }}$Sn 2+ activated fluosilicate (SFS) glass as a spectral converter for UVC detection has been prepared, which has a short lifetime (5.65 µs) and a high quantum efficiency (85%). The SFS decorated Si-based PIN photodiode enables strong absorption and subtly UVC shifts to an emission band optimized for the detector. Moreover, the outstanding performance of detection with responsivity of 27 µA/mW@278 nm, frequency limit up to 50 KHz, and rise/fall time scale of 15.14/18.71 µs@10 KHz is achieved. The comprehensive performance shows that SFS glass has the potential for efficient UVC detection in a scalable and low-cost strategy.