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A full analysis of 3-month Standardized Precipitation-Evapotranspiration index (SPEI-3) changes and attribution analyses are of significance for deeply understanding dryness/wetness evolutions and thus formulating specific measures to sustain regional development. In this study, we analyze monthly and annual SPEI-3 changes over Southwest China (SWC; including Sichuan (SC), Chongqing (CQ), Guizhou (GZ), Yunnan (YN), and west Guangxi (wGX)) during 1961–2012, using the SPEI model and routine meteorological measurements at 269 weather sites. For SWC and each subregion (excluding wGX), annual SPEI-3 during 1961–2012 tends to decrease, and drying is at most of months in January and September–December, but wetting is in February–August (excluding March for wGX). Additionally, more than 50% of sites show declined and increased SPEI-3 in January, April, June, and August–December and the remaining months, respectively. Except for wGX with dominant of ET0, annual SPEI-3 changes in SWC and other four subregions have dominant of precipitation. Spatially, annual SPEI-3 changes at 59% of sites are because of precipitation, generally located in southeast SC, south YN, CQ, GZ, and south and northeast wGX. Nevertheless, dominants at regional and site scales vary among months, e.g., SWC, SC, CQ, and GZ, having dominant of precipitation (ET0) during September–December (most of months during January–August), YN always with dominant of precipitation, and wGX with dominant of precipitation (ET0) in February–April and July–December (January, May, and June). Importantly, this study provides a reference for quantitatively evaluating spatiotemporal dryness/wetness variations with climate change, especially for regions with significant drying/wetting.

In this paper, a series of samples La0.7Sr0.3Mn1-xFexO3 (x = 0, 0.05, 0.10, 0.15, 0.2) were prepared. Among these samples, La0.7Sr0.3Mn0.85Fe0.15O3 showed better catalytic activity than the samples with undoped and other doped ones, so undoped iron La0.7Sr0.3MnO3 and doped iron La0.7Sr0.3Mn0.85Fe0.15O3 were characterized by X-ray diffraction (XRD), UV–Vis diffuse reflection analysis (UV–Vis DRS), vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), scanning electron microscope (SEM), specific surface analysis (BET), and X-ray photoelectron spectroscopy (XPS). In addition, it takes methyl orange (MO) as the object of degradation, and the photocatalysis, Fenton-like reaction, and their synergistic catalytic effects as well as the catalytic mechanisms of La0.7Sr0.3Mn0.85Fe0.15O3 have been studied. The results show that La0.7Sr0.3Mn0.85Fe0.15O3 exhibits high solar-driven photocatalytic and Fenton-like catalytic activities for MO degradation. Moreover, there is an obvious synergistic catalytic effect of photocatalysis and Fenton-like catalytic activity. In addition, according to the free radical capture experiment, the hole, •OH and •O2− are the active substances in the synergistic catalytic process. The possible synergistic catalytic mechanism of La0.7Sr0.3Mn0.85Fe0.15O3 was also proposed. And the average pore size of the catalyst is 20.91 nm by BET. The near-superparamagnetic properties of La0.7Sr0.3Mn0.85Fe0.15O3 enable it to achieve simple separation in an external magnetic field, avoiding the disadvantages of ordinary catalysts that are difficult to separate. Therefore, La0.7Sr0.3Mn0.85Fe0.15O3 is an advanced multifunctional nanocatalyst and could be widely used in the field of wastewater treatment. The magnetic La0.7Sr0.3Mn0.85Fe0.15O3 was synthesized by hydrothermal method successfully, the photocatalysis, Fenton-like reaction and their synergistic catalytic effects as well as the catalytic mechanisms of La0.7Sr0.3Mn0.85Fe0.15O3 have been studied, It is not only a high efficient solar-driven photocatalyst, but also has Fenton -like catalytic properties, and both of them have synergistic catalytic effect. And those indicate that La0.7Sr0.3Mn0.85Fe0.15O3 is an advanced multi-functional catalyst.

With intensifying climate change, droughts over Southwest China (SWC) are drawing increasing interest. The droughts of 2009–2011 have attracted special concern. However, the roles of atmospheric evaporative demand [reflected by reference evapotranspiration (ET0)] and precipitation (P) anomalies in drought evolutions are still unclear. To that end, we revisited the evolution of the 2009–2011 SWC meteorological droughts quantitatively and comprehensively by quantifying the ET0 and P impacts. In terms of three drought parameters [i.e., drought intensity (DI), area (DA), and duration (DD)], SWC experienced the second most severe drought of the 1961–2012 period in 2009. Evident differences existed among the drought conditions in different months, i.e., more severe droughts occurred in February–March 2009, September 2009 to March 2010, and June–October 2011. Based on the annual means over drought regions, the 2009 and 2011 DI (DA) could be attributed to lower P, but the P and ET0 impacts [P, ET0, and P-and-ET0 (which reflects drought occurrence due to their combined impacts only)] were comparable in 2010. In addition, P reduction was responsible for DD during 2009–2011. Except in January–March, which were dominated mostly by P, DI (DA) was generally dominated by ET0 (ET0 or P-and-ET0) over the three years. While P dominated spatially and temporally for the majority of the 36 months for DI (DD), some areas were mainly affected by ET0 (ET0 or P-and-ET0). Therefore, to better understand drought evolutions and improve drought monitoring and forecasting, the impacts of ET0 anomalies should be fully considered. The results of this study provide an important reference framework for comprehensively understanding the underlying mechanisms of droughts not only in SWC but also in other regions around the world.

The purpose of a battery thermal management system (BTMS) is to maintain the battery safety and efficient use as well as ensure the battery temperature is within the safe operating range. The traditional air-cooling-based BTMS not only needs extra power, but it could also not meet the demand of new lithium-ion battery (LIB) packs with high energy density, while liquid cooling BTMS requires complex devices to ensure the effect. Therefore, phase change materials (PCMs)-based BTMS is becoming the trend. By using PCMs to absorb heat, the temperature of a battery pack could be kept within the normal operating range for a long time without using any external power. PCMs could greatly improve the heat dissipation efficiency of BTMS by combining with fillers such as expanded graphite (EG) and metal foam for their high thermal conductivity or coordinating with fins. In addition, PCMs could also be applied in construction materials, solar thermal recovery, textiles and other fields. Herein, a comprehensive review of the PCMs applied in thermal storage devices, especially in BTMS, is provided. In this work, the literature concerning current issues have been reviewed and summarized, while the key challenges of PCM application have been pointed out. This review may bring new insights to the PCM application.

Despite numerous assessments of satellite-based and reanalysis precipitation across the globe, few studies have been conducted based on the precipitation linear trend (LT), particularly during daytime and nighttime, when there are different precipitation mechanisms. Herein, we first examine LTs for the whole day (LTwd), daytime (LTd), and nighttime (LTn) over mainland China (MC) in 2003–2017, with sub-daily observations from a dense rain gauge network. For MC and ten Water Resources Regions (WRRs), annual and seasonal LTwd, LTd, and LTn were generally positive but with evident regional differences. Subsequently, annual and seasonal LTs derived from six satellite-based and six reanalysis popular precipitation products were evaluated using metrics of correlation coefficient (CC), bias, root-mean-square-error (RMSE), and sign accuracy. Finally, metric-based optimal products (OPs) were identified for MC and each WRR. Values of each metric for annual and seasonal LTwd, LTd, or LTn differ among products; meanwhile, for any single product, performance varied by season and time of day. Correspondingly, the metric-based OPs varied among regions and seasons, and between daytime and nighttime, but were mainly characterized by OPs of Tropical Rainfall Measuring Mission (TRMM) 3B42, ECMWF Reanalysis (ERA)-Interim, and Modern Era Reanalysis for Research and Applications (MERRA)-2. In particular, the CC-based (RMSE-based) OPs in southern and northern WRRs were generally TRMM3B42 and MERRA-2, respectively. These findings imply that to investigate precipitation change and obtain robust related conclusions using precipitation products, comprehensive evaluations are necessary, due to variation in performance within one year, one day and among regions for different products. Additionally, our study facilitates a valuable reference for product users seeking reliable precipitation estimates to examine precipitation change across MC, and an insight (i.e., capacity in detecting LTs, including daytime and nighttime) for developers improving algorithms.

Here, we report the synthesis and neuroprotective capacity of 27 compounds with a bisphenol hydroxyl-substituted 1,2,4-triazole core or 1,2,4-oxadiazole core for stroke therapy. In vitro studies of the neuroprotective effects of compounds 1–27 on sodium nitroprusside (SNP)-induced apoptosis in PC12 cells indicate that compound 24 is the most effective compound conferring potent protection against oxidative injury. Compound 24 inhibits reactive oxygen species (ROS） accumulation and restores the mitochondrial membrane potential (MMP). Moreover, further analysis of the mechanism showed that compound 24 activates the antioxidant defence system by promoting the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and increasing the expression of haem oxygenase 1 (HO-1). An in vivo study was performed in a rat model of transient focal cerebral ischaemia generated by the intraluminal occlusion of the middle cerebral artery (MCAO). Compound 24 significantly reduced brain infarction and improved neurological function. Overall, compound 24 potentially represents a promising compound for the treatment of stroke.

Stratospheric winds play a significant role in middle atmosphere dynamics, model research, and carrier rocket experiments. For the first time, 65 sets of rocket sounding experiments conducted at Jiuquan (41.1°N, 100.2°E), China, from 1967 to 2004 are presented to study horizontal wind fields in the stratosphere. At a fixed height, wind speed obeys the lognormal distribution. Seasonal mean winds are westerly in winter and easterly in summer. In spring and autumn, zonal wind directions change from the upper to the lower stratosphere. The monthly zonal mean winds have an annual cycle period with large amplitudes at high altitudes. The correlation coefficients for zonal winds between observations and the Horizontal Wind Model (HWM) with all datasets are 0.7. The MERRA reanalysis is in good agreement with rocketsonde data according to the zonal winds comparison with a coefficient of 0.98. The sudden stratospheric warming is an important contribution to biases in the HWM, because it changes the zonal wind direction in the midlatitudes. Both the model and the reanalysis show dramatic meridional wind differences with the observation data.

Sounding rockets launched by China have collected data on the upper atmosphere for nearly 50 years. In this work, the data accuracy and variable characteristics of upper atmosphere temperature data, gathered at heights of 20–60 km over Jiuquan, China, during 1974–2014, were analyzed. The relative accuracy of sounding rocket temperature data was determined by comparing the data with Mass Spectrometer and Incoherent Scatter (MSIS) model data by season, and with Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) from the Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED) satellite by year. The sounding rocket temperature data showed differences from MSIS in every season, with the minimum difference occurring in summer, the next smallest difference in winter, and the maximum difference occurring in autumn. The sounding rocket data showed smaller differences from the SABER data, although the deviation still fluctuated depending on the date and hour of the observations. In addition, the temperature distributions of the temperature profiles were examined at different times at the same heights. By linearly fitting the mean temperature profiles of each season, the statistical characteristics of the temperature changes with height were explored.

As an essential variable in linking water, carbon, and energy cycles, evapotranspiration (ET) is difficult to measure. Remote sensing, reanalysis, and land surface model-based ET products offer comprehensive alternatives at different spatio-temporal intervals, but their performance varies. In this study, we selected four popular ET global products: The Global Land Evaporation Amsterdam Model version 3.0a (GLEAM3.0a), the Modern Era Retrospective-Analysis for Research and Applications-Land (MERRA-Land) project, the Global Land Data Assimilation System version 2.0 with the Noah model (GLDAS2.0-Noah) and the EartH2Observe ensemble (EartH2Observe-En). Then, we comprehensively evaluated the performance of these products over China using a stratification method, six validation criteria, and high-quality eddy covariance (EC) measurements at 12 sites. The aim of this research was to provide important quantitative information to improve and apply the ET models and to inform choices about the appropriate ET product for specific applications. Results showed that, within one stratification, the performance of each ET product based on a certain criterion differed among classifications of this stratification. Furthermore, the optimal ET (OET) among these products was identified by comparing the magnitudes of each criterion. Results suggested that, given a criterion (a stratification classification), the OETs varied among stratification classifications (the selected six criteria). In short, no product consistently performed best, according to the selected validation criterion. Thus, multi-source ET datasets should be employed in future studies to enhance confidence in ET-related conclusions.