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AbstractAs the unique rotating component, the impeller is the core component of a nuclear reactor coolant pump (RCP), the dynamic properties of the impeller are critical for the safe operation of the whole reactor. The purpose of this study was to shed comprehensive light on the pressure pulsation and modal properties of a scaled RCP impeller via experimental and numerical methods. The numerical model was validated by an experiment connecting the pressure pulsation signals at the diffuser inlet, and a good agreement was obtained between the numerical and experimental results. Pressure pulsation acting on the impeller's blade is mainly dominated by the impeller rotating frequency, the vane passing frequency, and the double blade‐passing frequency, and the pressure pulsation acting on the blade's pressure surface is more intense than on the suction surface. The modal properties were obtained via the modal test and numerical methods with the impeller suspended as a free body in the air and submerged inside water. The reduction in the impeller natural frequencies was between 31.63% and 37.77% for the corresponding mode shape due to the added mass effect of the fluid. Based on the pressure pulsation characteristics acting on the impeller and the natural frequency of the impeller, it is considered there is no risk of resonance in the impeller. Finally, it is expected that the present work can provide scientific guidance to avoid hydraulic resonance in nuclear reactor coolant pumps.

Los nodos de red de sensores inalámbricos tienen una energía limitada, la forma de emplear la energía limitada de manera eficiente para realizar una transmisión de datos efectiva se ha convertido en un tema candente. Teniendo en cuenta las características de la plantación de huertos en filas y sombras causadas por características aleatorias dispersas, para mejorar la eficiencia energética de la red de sensores inalámbricos de huertos y prolongar la vida útil de la red, proponemos un algoritmo mejorado de enrutamiento jerárquico de agrupamiento basado en cadenas (ICCHR) basado en el algoritmo de LIXIVIACIÓN. El algoritmo ICCHR investiga la formación de grupos, la elección de la cabeza del grupo, la formación de la cadena, así como el proceso de transmisión de datos, y además se simula con los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH a través de MATLAB. Los resultados de la simulación muestran que para BS en (50, 175), desde el punto de vista de la métrica de muerte de todos los nodos sensores, la vida útil de la red para el algoritmo ICCHR se prolonga aproximadamente 3.29, 8.78, 35.53 y 43.11% en comparación con los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH. El consumo medio de energía por ronda del algoritmo ICCHR es inferior a los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH en aproximadamente 4,73, 9,04, 35,60 y 43,31%. Esta investigación puede proporcionar referencias teóricas para las redes inalámbricas del entorno complejo del huerto. Les nœuds de réseau de capteurs sans fil ont une énergie limitée, comment utiliser efficacement une énergie limitée pour réaliser une transmission de données efficace est devenu un sujet brûlant. Compte tenu des caractéristiques de la plantation de vergers en rangées et à l'ombre causées par des caractéristiques aléatoires clairsemées, afin d'améliorer l'efficacité énergétique du réseau de capteurs sans fil du verger et de prolonger la durée de vie du réseau, nous proposons un algorithme amélioré de routage hiérarchique en grappe basé sur la chaîne (ICCHR) basé sur l'algorithme de LIXIVIATION. L'algorithme ICCHR étudie la formation de grappes, l'élection de la tête de grappe, la formation de la chaîne ainsi que le processus de transmission de données, et est ensuite simulé avec les algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH via Matlab. Les résultats de simulation montrent que pour BS à (50, 175), du point de vue de toutes les métriques de mort des nœuds du capteur, la durée de vie du réseau pour l'algorithme ICCHR prolonge d'environ 3,29, 8,78, 35,53 et 43,11% par rapport aux algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH. La consommation d'énergie moyenne par tour de l'algorithme ICCHR est inférieure à celle des algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH d'environ 4,73, 9,04, 35,60 et 43,31 %. Cette recherche peut fournir des références théoriques pour le réseau sans fil de l'environnement complexe du verger. Wireless sensor network nodes have limited energy, how to employ limited energy efficiently to realize effective data transmission has become a hot topic. Considering the characteristics of orchard planting in rows and shade caused by sparse random features, to improve energy efficiency of the orchard wireless sensor network and prolong network lifetime, we propose an improved chain-based clustering hierarchical routing (ICCHR) algorithm based on LEACH algorithm. The ICCHR algorithm investigates the formation of clusters, cluster head election, chain formation as well as the data transmission process, and further simulated with E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms through MATLAB. The simulation results show that for BS at (50, 175), from the point of view of all sensor nodes death metric, the network lifetime for ICCHR algorithm prolongs about 3.29, 8.78, 35.53, and 43.11% compared with E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms. The average energy consumption per round of the ICCHR algorithm is lower than E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms about 4.73, 9.04, 35.60, and 43.31%. This research can provide theoretical references for the orchard complex environment wireless networking. تتمتع عقد شبكة المستشعرات اللاسلكية بطاقة محدودة، وأصبحت كيفية استخدام الطاقة المحدودة بكفاءة لتحقيق نقل البيانات الفعال موضوعًا ساخنًا. بالنظر إلى خصائص زراعة البساتين في الصفوف والظل الناجم عن الميزات العشوائية المتفرقة، لتحسين كفاءة استخدام الطاقة لشبكة استشعار البساتين اللاسلكية وإطالة عمر الشبكة، نقترح خوارزمية محسنة للتوجيه الهرمي للتجميع القائم على السلسلة (ICCHR) بناءً على خوارزمية الرشح. تبحث خوارزمية المركز الدولي لحقوق الإنسان في تشكيل المجموعات واختيار رؤساء المجموعات وتشكيل السلسلة بالإضافة إلى عملية نقل البيانات، وتمت محاكاتها بشكل أكبر باستخدام خوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH من خلال MATLAB. تظهر نتائج المحاكاة أنه بالنسبة لـ BS عند (50، 175)، من وجهة نظر جميع مقاييس موت عقد المستشعرات، فإن عمر الشبكة لخوارزمية ICCHR يمتد إلى حوالي 3.29 و 8.78 و 35.53 و 43.11 ٪ مقارنة بخوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH. متوسط استهلاك الطاقة لكل جولة من خوارزميات المركز الدولي لحقوق الإنسان أقل من خوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH حوالي 4.73 و 9.04 و 35.60 و 43.31 ٪. يمكن أن يوفر هذا البحث مراجع نظرية لبيئة البستان المعقدة للشبكات اللاسلكية.

In the current situation with the unprecedented deployment of clean technologies for electricity generation, it is natural to expect that storage will play an important role in electricity networks. This paper provides a qualitative methodology to select the appropriate technology or mix of technologies for different applications. The multiple comparisons according to different characteristics distinguish this paper from others about energy storage systems. Firstly, the different technologies available for energy storage, as discussed in the literature, are described and compared. The characteristics of the technologies are explained, including their current availability. In order to gain a better perspective, availability is cross-compared with maturity level. Moreover, information such as ratings, energy density, durability and costs is provided in table and graphic format for a straightforward comparison. Additionally, the different electric grid applications of energy storage technologies are described and categorised. For each of the categories, we describe the available technologies, both mature and potential. Finally, methods for connecting storage technologies are discussed.

Considerable interest is being shown in using biochar production from waste biomass with a variety of disciplines to address the most pressing environmental challenges. Biochar produced by the thermal decomposition of biomass under oxygen-limited conditions is gaining popularity as a low-cost amendment for agro-ecosystems. The efficiency of biochar formation is affected by temperature, heating rate, feedstock type, particle size and reactor conditions. Properties such as pH, surface area and ash content of produced biochar increases with increasing temperatures. Biochar produced at lower heating rates may have high porosity and be beneficial for morphological changes in the soil. Biochar can help to enhance soil health and fertility as well as improve agricultural yield. As a result, biochar can assist in increasing food security by promoting sustainable agricultural systems and preserving an eco-friendly environment. Biochar is also widely being used as a sorbent for organic and inorganic pollutants, owing to its large surface area, allowing it to be immobilized from soil with ease. The functional groups and charges present on the surface of biochar play an important role in pollutants removal. This review focuses on the mechanisms of biochar production using different waste materials as a feed stock, factors that influence biochar quality as well as application of biochar in agricultural soil and their reclamation as well. This article also discusses knowledge gaps and future perspectives in the field of biochar-based toxic-pollution remediation.

Massive adoptions of combined heat and power (CHP) units necessitate the coordinated operation of power system and district heating system (DHS). Exploiting the reconfigurable property of district heating networks (DHNs) provides a cost-effective solution to enhance the flexibility of the power system by redistributing heat loads in DHS. In this paper, a unit commitment considering combined electricity and reconfigurable heating network (UC-CERHN) is proposed to coordinate the day-ahead scheduling of power system and DHS. The DHS is formulated as a nonlinear and mixed-integer model with considering the reconfigurable DHN. Also, an auxiliary energy flow variable is introduced in the formed DHS model to make the commitment problem tractable, where the computational burdens are significantly reduced. Extensive case studies are presented to validate the effectiveness of the approximated model and illustrate the potential benefits of the proposed method with respect to congestion management and wind power accommodation. (Corresponding author:Hongbin Sun)

Robust mitigation options will play significant role in achieving the target of limiting global change to below 1.5 °C above pre-industrial levels by 2100. To support cooperation for mitigation development, we establish a real options-based model to evaluate the rational decisions of exercising the abandon option for carbon capture and storage-enhanced oil recovery (CCS-EOR) projects under oil market and geological uncertainties. Three possible cooperative mechanisms (fixed carbon dioxide (CO2) price, oil-indexed CO2 price, and joint venture contracts) among CO2-EOR stakeholders are evaluated. The results show that the conflicts in profit maximization targets for different stakeholders in cooperative mitigation are to a great extent unable to be avoided. A joint venture business model is preferred in cooperative mitigation as it can effectively weaken such conflicts. And it is more reasonable to provide incentives to the downstream of the CO2-EOR chain than compensating the adoption cost of carbon capture technologies in the upstream. From a global perspective, the inefficient cooperation can be a main barrier that hinders the development of deep-cutting options. Global mitigation strategies should not only focus on promoting technology progress but also the design of innovative business models to balance the benefits among stakeholders. A joint venture business model is recommended in both the developed and developing countries for seizing the early mitigation opportunities.

For the first time, we here propose a green methodology to modify a low bandgap polymer for highly efficient solar cells using atmospheric pressure plasma jet or soft plasma operating on different feeding gases (air, Ar and N2). The physical properties of the modified polymer were investigated using conductivity measurements, UV-visible spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammograms, atomic force microscopy, cathodoluminescence and confocal Raman spectroscopy. Further, we examined the variation of the work function of the polymer before and after plasma treatment using a γ-focused ion beam. Additionally, photovoltaic cells based on the plasma-modified polymer having ITO/PEDOT:PSS/PHVTT (with or without plasma modification):PC71BM/LiF/Al configuration were fabricated and then characterized. We found that the power conversion efficiency (PCE) of the plasma-modified polymer increased dramatically as compared to the control polymer (without plasma treatment). PCE of the control polymer was found to be 4.11%, while after air, Ar and N2 gas plasma treatment the polymer showed PCEs of 4.85%, 4.87% and 5.14% respectively. Thus, plasma treatment not only alters the surface properties, but also modifies the bulk properties (changes in HOMO and LUMO bandgap level). Hence, this work provides new dimensions to explore more about plasma and polymer chemistry.

The growing population and increasing urbanization have led to a surge in domestic wastewater generation, posing significant challenges for effective and sustainable treatment. The present study demonstrates a novel and sustainable approach for the onsite treatment of domestic wastewater using an integrated settler-based biofilm reactor (ISBR) with efficient biogas generation. The ISBR provides an optimized environment for the growth of biofilm, facilitating the removal of organic pollutants and pathogens. Moreover, the ISBR enables the recovery of a valuable resource in the form of biogas, thus enhancing the overall utility of the treatment process. The performance of the ISBR was comprehensively evaluated at laboratory scale through treating the actual domestic wastewater generated from the hostel of Manipal University Jaipur. The ISBR system was operated under an ambient environment at a hydraulic retention time (HRT) of 24 h. The results demonstrated remarkable efficiency in terms of chemical oxygen demand (COD), total suspended solids (TSS), and coliforms removal, with average removal efficiency being more than 90%. According to the COD mass balance analysis, 48.2% of the influent COD was recovered as bioenergy. The chromatogram revealed a high percentage of methane gas in the collected biogas sample. The field emission scanning electron microscope (FESEM) analysis of the accumulated sludge in the ISBR system depicted the morphology of methanogenic bacteria. Both the experimental and theoretical results confirmed the feasibility and sustainability of the ISBR system at the onsite level.