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Abstract The Common Component Architecture (CCA) provides a means for software developers to manage the complexity of large-scale scientific simulations and to move toward a plug-and-play environment for high-performance computing. […]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Quantitatively and physically understanding changes in land surface hydrology is a hot topic in the hydro‐meteorological research, especially over China with high population density but uneven distribution of water resources. Therefore, the spatiotemporal dynamics (i.e., the 1980s [1981–1990] and 1990s [1991–2000] relative to the baseline of 1961–1980) in evapotranspiration (ET) and streamflow/runoff (Q) were examined across 426 hydrological divisions (HDs) of China. Both the 1980s and 1990s ET decreased over roughly 50% HDs mainly in the central and southeast parts of China, while the 1980s (1990s) Q decreased over slightly higher than 50% (63%) HDs generally in north and southwest China (the central and north parts of China). Relative to the 1980s, more HDs had strong changes in ET and Q in 1990s. Based on the separated contributions of precipitation (P), reference ET and Budyko‐type equation parameter n (an integrated variable of catchment property) to ET and Q changes, we found that in 1980s and 1990s, n dominated ET changes over about 60% HDs mainly in the south, with the dominant of P around 35% HDs generally in the north and northeast, while for Q changes, nearly 60% (slightly less than 40%) HDs were dominated by n (P). Moreover, the dominants for ET (Q) changes have shifted from 1980s to 1990s over 36% (45%) HDs, mainly changing from P to n. This study provides a framework for quantitatively understanding land surface hydrological dynamics from the perspectives of climatic and physiographic controls over regions. [ABSTRACT FROM AUTHOR]

We investigated controlling parameters of hardness in brittle materials by exploring the correlation between hardness and shear mode cracking. Density functional theory was used to calculate the unstable stacking energies (shear resistance to irreversible deformation) and the surface energies (tension resistance to fracture) for comparison. We found that both the unstable stacking energies and the surface energies had a monotonic relationship with hardness in Ge, Si, 3C-SiC, cBN, and diamond. In particular, both the relationship between hardness and the unstable stacking energy and the relationship between hardness and surface energy are better characterized as power law than linear relationships. Moreover, the surface energy has a better correlation with hardness than the unstable stacking energy. Both the theoretical stress for a crack to form and the stress intensity factor for a crack to propagate, which depend on surface energies, have better correlation with hardness than the stress intensity factor for a crack to emit a dislocation, which depends on unstable stacking energies. The implication of these results for fracture and deformation mechanism during hardness measurement is also discussed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this study, we estimated the respective contributions of precipitation and reference evapotranspiration (ET0) to annual SPEI‐3 (3‐month Standardized Precipitation‐Evapotranspiration Index) anomalies over southwest China (SWC) using numerical experiments. Results show that the dominant factor (i.e., precipitation or ET0) for the dryness/wetness anomalies during 1961–2012 existed due to inter‐annual and inter‐decadal changes over SWC, which indicates the underlying mechanisms of dry/wet conditions have changed. On the other hand, we calculate the dryness/wetness sensitivity to precipitation or ET0 (defined as changes in SPEI‐3 per millimetre) and find that the dryness/wetness sensitivity to ET0 is higher than that to precipitation for the whole SWC and the overwhelming majority (99%) of the 269 sites. Overall, the above findings imply that the role of ET0 in the dry/wet condition evolution is vital and should be paid more attentions. For the magnitude of the dryness/wetness sensitivity to precipitation or ET0, an evident increase from the southeast to northwest SWC is identified. Based on the analyses of the relationship between dryness/wetness sensitivity and climatological condition (i.e., precipitation, ET0, and aridity), the sensitivity magnitude is dependent on climatological precipitation and generally decreases with its increase. This study provides a wealth of quantitative information (e.g., dryness/wetness anomalies [sensitivity] caused by [to] precipitation and ET0) for better understanding the underlying mechanisms of the dry/wet condition evolution. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates reference evapotranspiration (ET0) trends in China from 1960 to 2012 based on the Penman–Monteith equation and gridded meteorological measurements. Under the combined impacts of factors influencing ET0 (i.e., net radiation [RN], mean temperature [TAVE], vapour pressure deficit [VPD], and wind speed [WND]), both seasonal and annual ET0 for the whole China and more than half of the grids decreased over the past 53 years. The attribution analyses suggest that for the whole China, the WND is responsible for annual and seasonal ET0 decreases (excluding summer, where RN is responsible). Across China, the annual cause of WND with the largest spatial extent (43.1% of grids) mainly derives from north of the Changjiang River Basin (CJRB), whereas VPD (RN) as a cause is dispersedly distributed (within and to the south of the CJRB). In summer, RN is dominant in more than half of the grids, but the dominance of VPD and WND accounts for approximately 90% of grids during the remaining seasons. Finally, the correlation coefficients between ET0 and the Atlantic Oscillation (AO), North AO, Indian Ocean Dipole (IOD), Pacific Decadal Oscillation (PDO), and El Niño Southern Oscillation (ENSO) indices with different lead times are calculated. For the whole China, annual and seasonal ET0 always significantly correlate with these indices (excluding the IOD) but with varied lead times. Additionally, near half of the grids show significant and maximum (i.e., the largest one between ET0 and a certain index with a lead time of 0–3 seasons) correlation coefficients of ET0 with PDO in spring and summer, ENSO in autumn, and AO in winter. This study is not only significant for understanding ET0 changes, but it also provides preliminary and fundamental reference information for ET0 prediction. [ABSTRACT FROM AUTHOR]

The monthly 3‐month Standardized Precipitation‐Evapotranspiration Index (SPEI‐3) over southwest China (SWC) shows obvious inter‐annual and inter‐decadal variability during 1961–2012. By examining the isolated contributions of precipitation and reference evapotranspiration (ET0) alone to the monthly SPEI‐3 anomalies, we find out that although anomalous precipitation plays a predominant role, ET0 impacts cannot be neglected, particularly during February–May. The monthly dryness/wetness sensitivity to precipitation (Sp; Set0 for ET0), that is, SPEI‐3 changes by per millimetre of precipitation (ET0) anomalies, is quantified as the slope of a linear regression, which has precipitation (ET0) contributions and anomalies during 1961–2012 as the dependent and the independent variables, respectively. Both SWC Sp and Set0 have evident intra‐annual differences, decreasing during February–August and increasing afterwards. Moreover, their magnitudes are dependent on climatological precipitation and generally decrease with precipitation increase. To sum up, the estimated respective contributions of monthly precipitation and ET0 anomalies are favourable for thoroughly understanding SWC dry/wet condition evolutions during the past 52 years. More importantly, Sp and Set0 are of significance for drought forecasting and emergency system over SWC. [ABSTRACT FROM AUTHOR]

SUMMARY Unconventional multi- and many-core processors (e.g. IBM ® Cell B.E. TM and NVIDIA ® GPU) have emerged as effective accelerators in trial climate and weather simulations. Yet these climate and weather models typically run on parallel computers with conventional processors (e.g. Intel ®, AMD ®, and IBM) using Message Passing Interface. To address challenges involved in efficiently and easily connecting accelerators to parallel computers, we investigated using IBM's Dynamic Application Virtualization TM (IBM DAV) software in a prototype hybrid computing system with representative climate and weather model components. The hybrid system comprises two Intel blades and two IBM QS22 Cell B.E. blades, connected with both InfiniBand ® (IB) and 1-Gigabit Ethernet. The system significantly accelerates a solar radiation model component by offloading compute-intensive calculations to the Cell blades. Systematic tests show that IBM DAV can seamlessly offload compute-intensive calculations from Intel blades to Cell B.E. blades in a scalable, load-balanced manner. However, noticeable communication overhead was observed, mainly due to IP over the IB protocol. Full utilization of IB Sockets Direct Protocol and the lower latency production version of IBM DAV will reduce this overhead. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Typical weather and climate models need a software tool to couple sub-scale model components. The high-performance computing requirements and a variety of model interfaces make the development of such a coupling tool very challenging. In this paper, we describe the approach of the Earth System Modeling Framework, in particular its component and coupling mechanism, and present the results of three cross-organization model interoperability experiments. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]