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AbstractThis work reports the synthesis, characterization, photophysical, and photovoltaic properties of five new thieno[3,2‐b][1]benzothiophene isoindigo (TBTI)‐containing low bandgap donor–acceptor conjugated polymers with a series of comonomers and different side chains. When TBTI is combined with different electron‐rich moieties, even small structural variations can have significant impact on thin film morphology of the polymer:phenyl C70 butyric acid methyl ester (PCBM) blends. More importantly, high‐resolution electron energy loss spectroscopy is used to investigate the phase‐separated bulk heterojunction domains, which can be accurately and precisely resolved, enabling an enhanced correlation between polymer chemical structure, photovoltaic device performance, and morphology.

La sécheresse agricole est l'un des risques agricoles les plus dommageables dans le monde qui peut entraîner des pertes agricoles importantes et une pénurie d'eau. L'utilisation d'images satellites pour surveiller la sécheresse agricole a fait l'objet d'une attention croissante de la part des chercheurs et a également été appliquée à l'échelle régionale et mondiale. Dans cet article, la température de surface de la terre (LST) et les produits d'éclat du nouveau Sentinel-3A SLSTR (radiomètre de température de surface de la mer et de la terre) lancé par l'Agence spatiale européenne (ESA) sont utilisés pour la première fois pour estimer l'indice de condition de température de la végétation (VTCI), qui à son tour est utilisé pour surveiller la sécheresse agricole dans la plaine de Hetao en Mongolie intérieure, en Chine. Cet article analyse initialement la corrélation entre le LST et l'indice de végétation à différence normalisée (NDVI) en utilisant des séries temporelles MODIS LST et NDVI dans différentes conditions de croissance de la végétation. Les résultats révèlent que VTCI ne peut être utilisé que pendant les saisons chaudes (fin du printemps et période estivale) lorsque des corrélations négatives entre LST et NDVI sont observées. Par conséquent, les images VTCI sont capturées dans la zone d'étude entre juillet et août 2017 à l'aide de Sentinel-3A SLSTR LST et NDVI et sont utilisées pour l'enquête sur la sécheresse. Ces images révèlent que le VTCI moyen des pixels des terres cultivées dans la zone d'étude est passé de 0,4511 le 28 juillet à 0,5229 le 12 août avant de diminuer à 0,4710 le 18 août en raison des précipitations de la première période, indiquant ainsi que VTCI a une réponse opportune aux précipitations. Pendant ce temps, la comparaison croisée des valeurs VTCI de Sentinel-3A SLSTR montre une grande cohérence en termes de distribution spatiale avec celle estimée à partir des produits EOS MODIS. La différence entre ces indices variait de −0,1 à 0,1 pour la plupart des points, en particulier dans la couverture terrestre cultivée. Dans l'ensemble, les résultats appuient l'utilisation des produits LST et NDVI de Sentinel-3A SLSTR dans la surveillance de la sécheresse agricole. La sequía agrícola es uno de los peligros agrícolas más dañinos en todo el mundo que puede provocar importantes pérdidas agrícolas y escasez de agua. El uso de imágenes satelitales para monitorear la sequía agrícola ha recibido cada vez más atención de la investigación y también se ha aplicado a escala regional y mundial. En este documento, la temperatura de la superficie terrestre (LST) y los productos de radiancia del nuevo Sentinel-3A SLSTR (radiómetro de temperatura de la superficie del mar y la tierra) lanzado por la Agencia Espacial Europea (esa) se utilizan por primera vez para estimar el índice de condición de temperatura de la vegetación (VTCI), que a su vez se utiliza para monitorear la sequía agrícola en la llanura de Hetao de Mongolia Interior, China. Este documento analiza inicialmente la correlación entre LST y el índice de vegetación de diferencia normalizada (NDVI) mediante el uso de productos MODIS LST y NDVI de series de tiempo en diferentes condiciones de crecimiento de la vegetación. Los hallazgos revelan que el VTCI solo se puede usar en estaciones cálidas (finales de los períodos de primavera y verano) cuando se observan correlaciones negativas entre LST y NDVI. Por lo tanto, las imágenes de VTCI se capturan en el área de estudio entre julio y agosto de 2017 mediante el uso de Sentinel-3A SLSTR LST y NDVI y se utilizan para la investigación de la sequía. Estas imágenes revelan que el VTCI promedio de los píxeles de tierra cultivada en el área de estudio ha aumentado de 0.4511 el 28 de julio a 0.5229 el 12 de agosto antes de disminuir a 0.4710 el 18 de agosto debido a las precipitaciones en el primer período, lo que indica que el VTCI tiene una respuesta oportuna a las precipitaciones. Mientras tanto, la comparación cruzada de los valores de VTCI de Sentinel-3A SLSTR muestra una alta consistencia en términos de distribución espacial con la estimada de los productos EOS MODIS. La diferencia entre estos índices osciló entre -0,1 y 0,1 para la mayoría de los puntos, especialmente en la cubierta vegetal cultivada. En general, los hallazgos respaldan el uso de los productos LST y NDVI de Sentinel-3A SLSTR en el monitoreo de la sequía agrícola. Agricultural drought is one of most damaging agricultural hazards worldwide that can bring significant agricultural losses and water scarcity. The use of satellite images for monitoring agricultural drought has received increasing research attention and has also been applied at both the regional and global scales. In this paper, the land surface temperature (LST) and radiance products of the new Sentinel-3A SLSTR (sea and land surface temperature radiometer) launched by European Space Agency (ESA) are used for the first time for estimating the vegetation temperature condition index (VTCI), which in turn is used for monitoring agricultural drought in the Hetao Plain of Inner Mongolia, China. This paper initially analyzes the correlation between LST and normalized difference vegetation index (NDVI) by using time series time MODIS LST and NDVI products under different vegetation growth conditions. The findings reveal that VTCI can only be used in warm seasons (late spring and summer periods) when negative correlations between LST and NDVI are observed. Therefore, VTCI images are captured in the study area between July and August 2017 by using Sentinel-3A SLSTR LST and NDVI and are utilized for drought investigation. These images reveal that the average VTCI of the cultivated land pixels in the study area has increased from 0.4511 on July 28 to 0.5229 on August 12 before declining to 0.4710 on August 18 due to the rainfall in the first period, thereby indicating that VTCI has a timely response to rainfall. Meanwhile, cross-comparison of VTCI values from Sentinel-3A SLSTR shows high consistency in terms of spatial distribution with that estimated from EOS MODIS products. The difference between these indices ranged from −0.1 to 0.1 for most points, especially in the cultivated land cover. Overall, the findings support the use of the LST and NDVI products of Sentinel-3A SLSTR in monitoring agricultural drought. يعد الجفاف الزراعي أحد أكثر المخاطر الزراعية ضررًا في جميع أنحاء العالم والذي يمكن أن يؤدي إلى خسائر زراعية كبيرة وندرة المياه. حظي استخدام صور الأقمار الصناعية لرصد الجفاف الزراعي باهتمام بحثي متزايد وتم تطبيقه أيضًا على المستويين الإقليمي والعالمي. في هذه الورقة، يتم استخدام درجة حرارة سطح الأرض (LST) ومنتجات الإشعاع الخاصة بالمقياس الإشعاعي الجديد Sentinel -3A SLSTR (مقياس درجة حرارة سطح البحر والأرض) الذي أطلقته وكالة الفضاء الأوروبية (ESA) لأول مرة لتقدير مؤشر حالة درجة حرارة الغطاء النباتي (VTCI)، والذي يستخدم بدوره لرصد الجفاف الزراعي في سهل هيتاو في منغوليا الداخلية، الصين. تحلل هذه الورقة في البداية العلاقة بين LST ومؤشر الاختلاف الطبيعي للغطاء النباتي (NDVI) باستخدام السلاسل الزمنية لمنتجات MODIS LST و NDVI في ظل ظروف نمو مختلفة للغطاء النباتي. تكشف النتائج أنه لا يمكن استخدام VTCI إلا في المواسم الدافئة (أواخر فصلي الربيع والصيف) عند ملاحظة الارتباطات السلبية بين LST و NDVI. لذلك، يتم التقاط صور VTCI في منطقة الدراسة بين يوليو وأغسطس 2017 باستخدام Sentinel -3A SLSTR LST و NDVI وتستخدم للتحقيق في الجفاف. تكشف هذه الصور أن متوسط VTCI لبكسلات الأراضي المزروعة في منطقة الدراسة قد ارتفع من 0.4511 في 28 يوليو إلى 0.5229 في 12 أغسطس قبل أن ينخفض إلى 0.4710 في 18 أغسطس بسبب هطول الأمطار في الفترة الأولى، مما يشير إلى أن VTCI لديها استجابة في الوقت المناسب لهطول الأمطار. وفي الوقت نفسه، تُظهر المقارنة المتقاطعة لقيم VTCI من Sentinel -3A SLSTR اتساقًا عاليًا من حيث التوزيع المكاني مع تلك المقدرة من منتجات EOS MODIS. تراوح الفرق بين هذه المؤشرات من -0.1 إلى 0.1 لمعظم النقاط، خاصة في الغطاء الأرضي المزروع. بشكل عام، تدعم النتائج استخدام منتجات LST و NDVI من Sentinel -3A SLSTR في مراقبة الجفاف الزراعي.

For the purpose of efficiency improvement, a linear motor that performs a linear reciprocating motion can be employed to directly drive the piston in a reciprocating refrigeration compressor without crankshaft mechanism. This also facilitates the modulation of cooling capacity as the stroke and frequency can be readily varied in response to heat load. A novel design of moving magnet linear motor for linear compressor was analyzed in the paper. A finite element analysis (FEA) model was built to simulate the characteristics of the linear motor. Current and displacement signals were measured from a test rig and were defined in the transient FEA model. Transient motor force was simulated with the FEA model and good agreements are shown between the results from the FEA model and interpolated shaft force from static force measurements. Major Losses, such as copper loss and core loss were also computed. Motor efficiency decreased from 0.88 to 0.83 as stroke increased from 9 mm to 12 mm, while the pressure ratio remained unchanged. Comparisons were made between the present moving magnet linear motor and moving coil linear motors. Generally, the moving magnet linear motor demonstrates higher efficiency than moving coil motors, which have significantly higher copper loss. The present moving magnet design with simple structure could be further optimized to improve motor efficiency.

As part of the UV-Indien project, a station for measuring ultraviolet radiation and the cloud fraction was installed in December 2019 in Moroni, the capital of the Comoros, situated on the west coast of the island of Ngazidja. A ground measurement campaign was also carried out on 12 January 2020 during the ascent of Mount Karthala, located in the center of the island of Ngazidja. In addition, satellite estimates (Ozone Monitoring Instrument and TROPOspheric Monitoring Instrument) and model outputs (Copernicus Atmospheric Monitoring Service and Tropospheric Ultraviolet Model) were combined for this same region. On the one hand, these different measurements and estimates make it possible to quantify, evaluate, and monitor the health risk linked to exposure to ultraviolet radiation in this region, and, on the other, they help to understand how cloud cover influences the variability of UV-radiation on the ground. The measurements of the Ozone Monitoring Instrument onboard the EOS-AURA satellite, being the longest timeseries of ultraviolet measurements available in this region, make it possible to quantify the meteorological conditions in Moroni and to show that more than 80% of the ultraviolet indices are classified as high and that 60% of these are classified as extreme. The cloud cover measured in Moroni by an All Sky Camera was used to distinguish between the cases of UV index measurements taken under clear or cloudy sky conditions. The ground-based measurements thus made it possible to describe the variability of the diurnal cycle of the UV index and the influence of cloud cover on this parameter. They also permitted the satellite measurements and the results of the simulations to be validated. In clear sky conditions, a relative difference of between 6 and 11% was obtained between satellite or model estimates and ground measurements. The ultraviolet index measurement campaign on Mount Karthala showed maximum one-minute standard erythemal doses at 0.3 SED and very high daily cumulative erythemal doses at more than 80 SED. These very high levels are also observed throughout the year and all skin phototypes can exceed the daily erythemal dose threshold at more than 20 SED.

Thermal management systems are integral to electric and hybrid vehicle battery packs for maximising safety and performance since high and irregular battery temperatures can be detrimental to these criteria. Lithium-ion batteries are the most commonly used in the electric vehicle (EV) industry because of their high energy and power density and long life cycle. Liquid cooling provides superior performance with low power draw and high heat transfer coefficient. Two liquid cooling designs-the Linear Channel Design (LCD) and Helical Channel Design (HCD)-underwent multiple numerical and geometrical optimisations, where inlet mass flow rate, channel diameter, and inlet and outlet locations were analysed using CFD (computational fluid dynamics). The primary objectives were to maintain maximum temperatures and thermal uniformity within the operational limits derived from the literature. These were both achieved with the LCD using a mass flow rate of 7.50E-05 kgs−1. The Tmax goal was met for the HCD but not the thermal uniformity goal. The LCD achieved 1.796 K lower in maximum temperature and 8.740 K lower in temperature difference compared to the HCD, proving itself superior in both metrics. The HCD required a higher mass flow rate than the LCD to regulate temperatures, resulting in an undesirably high power consumption.

AbstractRevolutionary changes in energy storage technology have put forward higher requirements on next‐generation anode materials for lithium‐ion battery. Recently, a new class of materials with complex stoichiometric ratios, high‐entropy oxide (HEO), has gradually emerging into sight and embracing the prosperity. The ideal elemental adjustability and attractive synergistic effect make HEO promising to break through the integrated performance bottleneck of conventional anodes and provide new impetus for the design and development of electrochemical energy storage materials. Here, the research progress of HEO anodes is comprehensively reviewed. The driving force behind phase stability, the role of individual cations, potential mechanisms for controlling properties, as well as state‐of‐the‐art synthetic strategies and modification approaches are critically evaluated. Finally, we envision the future prospects and related challenges in this field, which will bring some enlightening guidance and criteria for researchers to further unlock the mysteries of HEO anodes.image

Abstract Aphid populations frequently include phenotypes that are resistant to parasitism by hymenopterous parasitoid wasps, which is often attributed to the presence of ‘protective’ facultative endosymbionts residing in aphid tissues, particularly Hamiltonella defensa. In field conditions, under parasitoid pressure, the observed coexistence of aphids with and without protective symbionts cannot be explained by their difference in fitness alone. Using the cereal aphid Rhopalosiphum padi as a model, we propose an alternative mechanism whereby parasitoids are more efficient at finding common phenotypes of aphid and experience a fitness cost when switching to the less common phenotype. We construct a model based on delay differential equations and parameterize and validate the model with values within the ranges obtained from experimental studies. We then use it to explore the possible effects on system dynamics under conditions of environmental stress, using our existing data on the effects of drought stress in crops as an example. We show the ‘switching penalty’ incurred by parasitoids leads to stable coexistence of aphids with and without H. defensa and provides a potential mechanism for maintaining phenotypic diversity among host organisms. We show that drought‐induced reduction in aphid development time has little impact. However, greater reduction in fecundity on droughted plants of symbiont‐protected aphids can cause insect population cycles when the system would be stable in the absence of drought stress. The stabilizing effect of the increased efficiency in dealing with more commonly encountered host phenotypes is applicable to a broad range of consumer–resource systems and could explain stable coexistence in competitive environments. The loss of stable coexistence when drought has different effects on the competing aphid phenotypes highlights the importance of scenario testing when considering biocontrol for pest management.

In the plight for sustainable development and to support net zero ambitions for climate change mitigation, a broad range of aeration strategies have been developed with the hope of improving efficiency to minimize environmental and economic costs associated with the wastewater treatment processes. However, a balance is levied between reducing oxygen availability and hindering aerobic processes thus compromising performance. In the present work, we evaluate and compare the sustainability of a range of investigated strategies including continuous aeration (CA) at different dissolved oxygen (DO) setpoints (0.5 mg/L, 2.5 mg/L, 4.5 mg/L) and intermittent aeration (IA) at different oxic-anoxic portions (2.5 h on/0.5 h off, 2.0 h on/1.0 h off, 1.5 h on/1.0 h off). To achieve this, an eco-efficiency assessment is performed based on the results of previous life cycle impact and costing analyses for each strategy, while also incorporating a third factor to account for their respective treatment performance. The results demonstrate a clear pattern of increased sustainability for the IA strategies (0.54–0.56 Pt/m3), compared to the CA strategies (0.76–0.77 Pt/m3). While only negligible difference was observed within each aeration type, the trade-off between environmental and economic efficiency and treatment performance was distinct in CA strategies. At the individual pollutant level, IA strategies demonstrated decreasing sustainability for total phosphorous (TP) removal as the anoxic cycle portion increased, while CA at 0.5 mg/L was shown to be the most sustainable strategy for the removal of this pollutant (0.61 Pt/m3). Further work is suggested to incorporate the relative N2O emissions generated by each strategy and to investigate other strategies based on automated control. Sanitary Engineering