Research on optimal coil configuration scheme of insulator relay WPT system

This paper presents the optimized structure of the multi-relay coils insulator of WPT system. With the rapid development of the smart grid, on-line monitoring devices in the transmission tower have been widely used. However, the power supply problem has become an important bottleneck in the development of transmission tower intelligent sensing technology. Hence, the multi-relay coils wireless power transfer technology has been proposed to supply for the tower monitoring equipment in this paper. Compared with traditional multi-relay coils, the effects of the number, arrangement position and turns of relay coils on the performance of WPT system are further explored. The simulation results show that the operation performance of WPT can be significantly improved by optimizing the coil arrangement position and turns. Moreover, there are multiple configuration schemes that the design indexes of the system could be achieved. The experiment results show that in the 110 kV high-voltage transmission with the insulator length of 1.015 m, the transmitting power and efficiency of the WPT system could be increased to 1.81 W and 60.11% respectively by parameters optimization, which ensures the continuous and stable work of the monitoring equipment

Acetate favors more phosphorus accumulation into aerobic granular sludge than propionate during the treatment of synthetic fermentation liquor

Anaerobic digestion (AD) is an efficient biotechnology widely applied for energy and resource recovery from organic waste and wastewater treatment. The effluent from AD or fermentation liquor containing organic substances like volatile fatty acids (VFAs) and mineral nutrients (such as N and P), however, will trigger serious environmental issues if not properly dealt with. In this study two identical sequencing batch reactors (SBRs), namely Ra and Rp were used to cultivate aerobic granules for P recovery from synthetic fermentation liquor, respectively using acetate and propionate as additional carbon source. Larger and more stable granules were achieved in Ra with higher P removal capability (9.4 mg P/g-VSS·d) and higher anaerobic P release (6.9 mg P/g-VSS·h). In addition to much higher P content (78 mg P/g-SS), bioavailable P in Ra-granules increased to 45 mg P/g-SS, approximately 2-times those of seed sludge and Rp-granules. Microbial community analysis indicated that more GAOs were accumulated in Rp-granules

The relationship between resilience and quality of life in advanced cancer survivors: multiple mediating effects of social support and spirituality

BackgroundWhile previous studies have revealed a positive association between resilience and quality of life in advanced cancer survivors, the mechanisms of the relationship is still unclear. This study aimed to explore the relationships between resilience, social support, spirituality, and quality of life and determine the multiple mediation effects of social support and spirituality on the relationship between resilience and quality of life.MethodsWith 286 advanced cancer survivors, a cross-sectional, correlational survey was adopted using convenience sampling. Resilience, social support, spirituality, and quality of life were evaluated by self-report questionnaires. The PROCESS macro for SPSS was used to test the multiple mediation model.ResultsThe scores for resilience, social support, spirituality and quality of life were positively correlated with one another. Resilience was found to be directly impact quality of life. Meanwhile, the relationship between resilience and quality of life was mediated by social support (effect = 0.067, 95% CI [0.019, 0.120]) and by spirituality (effect = 0.221, 95% CI [0.134, 0.332]), respectively, and by these two serially (effect = 0.036, 95% CI [0.015, 0.067]).ConclusionSocial support and spirituality played multiple mediating roles in the relationship between resilience and quality of life. Interventions aimed at increasing resilience, and then boosting social support and spirituality may be beneficial for promoting quality of life of advanced cancer survivors

Identification of inorganic and organic species of phosphorus and its bio-availability in nitrifying aerobic granular sludge

Phosphorus (P) recovery from sewage sludge is necessary for a sustainable development of the environment and thus the society due to gradual depletion of non-renewable P resources. Aerobic granular sludge is a promising biotechnology for wastewater treatment, which could achieve P-rich granules during simultaneous nitrification and denitrification processes. This study aimed to disclose the changes in inorganic and organic P species and their correlation with P mobility and bio-availability in aerobic granules. Two identical square reactors were used to cultivate aerobic granules, which were operated for 120 days with influent ammonia nitrogen (NH4–N) of 100 mg/L before day 60 and then increased to 200 mg/L during the subsequent 60 days (chemical oxygen demand (COD) was kept constant at 600 mg/L). The aerobic granules exhibited excellent COD removal and nitrification efficiency. Results showed that inorganic P (IP) was about 61.4–67.7% of total P (TP) and non-apatite inorganic P (NAIP) occupied 61.9–70.2% of IP in the granules. The enrichment amount of NAIP and apatite P (AP) in the granules had strongly positive relationship with the contents of metal ions, i.e. Fe and Ca, respectively accumulated in the granules. X-ray diffraction (XRD) analysis and solution index calculation demonstrated that hydroxyapatite (Ca5(PO4)3(OH)) and iron phosphate (Fe7(PO4)6) were the major P minerals in the granules. Organic P (OP) content maintained around 7.5 mg per gram of biomass in the aerobic granules during the 120 days\u27 operation. Monoester phosphate (21.8% of TP in extract), diester phosphate (1.8%) and phosphonate (0.1%) were identified as OP species by Phosphorus-31 nuclear magnetic resonance (31P NMR). The proportion of NAIP + OP to TP was about 80% in the granules, implying high potentially mobile and bio-available P was stored in the nitrifying aerobic granules. The present results provide a new insight into the characteristics of P species in aerobic granules, which could be helpful for developing P removal and recovery techniques through biological wastewater treatment

Effect of the 6PBT stirrer eccentricity and off-bottom clearance on mixing of pseudoplastic fluid in a stirred tank

The aim of this work is to investigate the effect of the shaft eccentricity on the flow field and mixing characteristics in a stirred tank with the novel stirrer composed of perturbed six-bent-bladed turbine (6PBT). The difference between coaxial and eccentric agitations is studied using computational fluid dynamics (CFD) simulations combined with standard k−ε turbulent equations, that offer a complete image of the three-dimensional flow field. In order to determine the capability of CFD to forecast the mixing process, particle image velocimetry (PIV), which provide an accurate representation of the time-averaged velocity, was used to measure fluid velocity. The test liquid used was 1.25% (wt) xanthan gum solution, a pseudoplastic fluid with a yield stress. The comparison of the experimental and simulated mean flow fields has demonstrated that calculations based on Reynolds-averaged Navier-Stokes equations are suitable for obtaining accurate results. The effects of the shaft eccentricity and the stirrer off-bottom distance on the flow model, mixing time and mixing efficiency were extensively analyzed. It is observed that the microstructure of the flow field has a significant effect on the tracer mixing process. The eccentric agitation can lead to the flow model change and the non-symmetric flow structure, which would possess an obvious superiority of mixing behavior. Moreover, the mixing rate and mixing efficiency are dependent on the shaft eccentricity and the stirrer off-bottom distance, showing the corresponding increase of the eccentricity with the off-bottom distance. The efficient mixing process of pseudoplastic fluid stirred by 6PBT impeller is obtained with the considerably low mixing energy per unit volume when the stirrer off-bottom distance, C, is T/3 and the eccentricity, e, is 0.2. The research results provide valuable references for the improvement of pseudoplastic fluid agitation technology. Keywords: Eccentric agitation, Pseudoplastic fluid, Mixing efficiency, Eccentricit

Study on mechanism of carbonaceous gold ore during oxidation roasting by kinetics: phase transformation and structure evolution

The pretreatment and effective utilization of carbonaceous gold ore is of significant to refractory gold resources. In this work, the calcination kinetics was employed to investigate the relationship between phase transformation and structure evolution of carbonaceous gold ore during roasting process. Mechanism functions were determined and the fact that roasting process was controlled by chemical reaction in the initial 90 min and dominated by internal diffusion as time reached to 120 min was uncovered. In addition, the apparent activation energies for initial and latter roasting stage were 212.11 kJ·mol ^−1 and 163.73 kJ·mol ^−1 , respectively. Combined with the analysis of phase transformation and structure evolution, the removal of carbonaceous matter and appearance of new tiny pores contributed to the change of calcination kinetics. Moreover, phase transformation and structure evolution were beneficial for elevating Au recovery during leaching experiment. These findings helped to understand the mechanism of carbonaceous minerals during roasting and provided new insight for the utilization of refractory gold resource

An automatic performance model-based scheduling tool for coupled climate system models

The prediction of the climate system is highly depended on the efficient integration of observations and simulations of the Earth. This is regarded as a canonical example of the cyber-physical system. The climate system model, the simulation engine in this cyber-physical system, is one of most challenging applications in scientific computing. It utilizes the multi-physics simulation that couples multiple components, conducts decadal to millennium simulations, and has long been an important application on supercomputers. However, current climate system models suffer from the inefficient task scheduling methods resulting in an intolerable simulation time. Take the Community Earth System Model (CESM), the most widely used climate system model, as an example, one major reason that CESM suffers from bad performances is the huge overhead to rationally distribute processes among the coupled heterogeneous components. According to the report of NCAR, every percent improvement in CESM performance frees up to the equivalent of $250,000 in computing resources in their scientific experiments. To address such challenge, our paper firstly constructs a lightweight and accurate performance model for effectively capturing and predicting the heterogeneous time-to-solution performance of end-to-end CESM components with a given simulation configuration. Then, based on the performance model, we further propose an efficient scheduling strategy based on rectangular packing method to determine the best process layout among different components, and the process numbers assigned to each component. Our evaluations show that we can achieve 58$40,089 with a charge of $0.01 per CPU hour. Meanwhile, 26% extra performance improvements could also be gained in our methods comparing to the heuristic branch and bound algorithm with the guidance of the known curve-fitting performance model

Sensitive readout of implantable microsensors using a wireless system locked to an exceptional point

https://doi.org/10.1038/ s41928-019-0284-42335–34