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Currently, in the domestic practice of retreading tires using vulcanization tanks, some tanks exhibit uneven temperature distributions leading to low retreading success rates. To address that, this paper simulated the temperature and velocity fields during the heating process of vulcanization tanks for waste tire retreading. The results indicated that a higher heating power reduces the time required for the vulcanizing agent to reach the vulcanization condition, but it also increases the difference in tire temperature in the tank, with a severely uneven distribution of the temperature field. Subsequently, to improve the uniformity of temperature distribution and enhance the retreading rate of waste tires, this paper proposed two types of orifice plates to adjust the airflow organization. The results show that both the plain orifice plate and the frustum cone orifice plate can enhance the uniformity of the temperature field within the vulcanization tank and reduce the temperature difference between tires. Moreover, at the same heating power, the presence of the orifice plates increases the rate of temperature increase in the tires and the vulcanizing agent compared to the original vulcanization tank, improving the thermal efficiency of the vulcanization tank heater. [ABSTRACT FROM AUTHOR]

In recent years, highway infrastructure in the Ningxia region of China has rapidly advanced. Cement–loess is extensively utilized in the roadbed and foundation reinforcement. It is necessary to conduct micro–macro-analysis and model derivation of the electrical resistivity on Ningxia cement–loess, which are beneficial for both the practical application of electrical resistivity and the evaluation of the geotechnical properties of cement–loess. Therefore, a series of electrical resistivity measurements, microstructural observations (scanning electron microscopy), mineral analyses (thermogravimetric analysis), and theoretical analyses were adopted on the cement–loess. The following conclusions can be drawn: The electrical resistivity is negatively related to dry density and water content, while it is positively related to cement dosage and curing age. A cement dosage of 6% exhibits a lower hydration reaction potential compared to 12%, causing a slower increase in electrical resistivity. The formation of calcium silicate gel around particles results in particle clustering and pore filling, reducing the pore area and increasing electrical resistivity. Increased hydration also decreases microscopic orientation, contributing to a higher electrical resistivity of cement–loess. Finally, a new three-dimensional electrical resistivity model was created, finding that the electrical resistivity of Ningxia cement–loess was determined by the dry density, water content (ρd·w), cement dosage, and curing age (aw·T) in an exponential function form. The new three-dimensional electrical resistivity model could be used in the high-efficiency evaluation of the cement–loess geotechnical parameter, offering valuable insights for the monitoring and maintenance of road infrastructure. [ABSTRACT FROM AUTHOR]

In China, a large amount of the total energy consumption is made up of building energy, particularly in humid regions. The conventional vapor compression refrigeration systems cannot effectively control the indoor humid and thermal environment. Therefore, this article proposes a solar-powered desiccant wheel and ground-source heat pump (SDW-GSHP) air conditioning system. The energy consumption of the system is mainly from sustainable sources of solar and geothermal energy, showcasing excellent energy efficiency and environmental friendliness. The desiccant wheel (DW) processes latent heat loads, and the GSHP processes the sensible heat load. The regeneration air of the DW is heated by a solar collector. The operational performance of the system was simulated by using TRNSYS during the typical summer week (15 July to 22 July) in Qingdao. The simulation results indicated that indoor temperature was maintained within 25.8–26.2 °C and the relative humidity was maintained in the range of 57–61%. The COP of the SDW-GSHP air conditioning system was 42.1% higher than that of the DW air conditioning system with electric heating regeneration, and electricity saved 43.7%. [ABSTRACT FROM AUTHOR]

The pyrolysis of waste tires has been considered a potential sustainable solution in light of escalating carbon dioxide emissions. Nevertheless, current research indicates a lack of comprehensive understanding regarding the movement of waste tire particles in a single horizontal-axis stirred pyrolysis reactor. This study employed EDEM 2021.2 software to perform comprehensive numerical simulations of a single horizontal-axis stirred pyrolysis reactor, examining the impact of three main production factors—particle size, feed rate, and central axis speed—on particle motion. By acquiring contact data between particles and reactor walls, we illustrated the persistent motion of particles during the operation of the equipment. The research findings suggest that with the rise in rotational speed, there is a corresponding increase in particle accumulation. In high-speed conditions, the interaction between particles and the reactor wall is intensified. The contact level increased by 15.54% (at 3 r/min) and 25.66% (at 5 r/min) with the rise in rotational speed. Furthermore, at an identical rotational speed, the interaction between the larger particle group and the wall surpassed that of the smaller particle group. Doubling the feed rate led to a reduction of over 10% in the contact level between particles and the reaction wall at varying speeds. Through a thorough analysis of various factors influencing particle motion, our objective is to elucidate the motion traits of particles in the reactor, offering crucial theoretical direction and technical assistance to enhance production efficiency and ensure the secure and steady operation of pyrolysis reactors. [ABSTRACT FROM AUTHOR]

Background: The COVID‐19 pandemic worldwide has caused varying degrees of severity of lung damage in patients, with acute respiratory distress and death in severe cases. However, this is not directly caused by the virus itself, but by the production of inflammasome by monocytes in the body, leading to a systemic inflammatory response, which results in a very poor clinical prognosis for patients with COVID‐19. Objective: The purpose of this meta‐analysis was to look at the relationship between hypernatremia and mortality in COVID‐19 patients. Methods: We searched the PubMed, Web of Science, Embase, and Cochrane databases for articles published from the inception of the database until August 27, 2022. Three researchers reviewed the literature, retrieved data, and assessed the quality of the literature, respectively. A meta‐analysis was performed using State 17 software to assess the value of the effect of hypernatremia on mortality in patients with new coronavirus pneumonia. Results: A total of nine publications was finally included in this study, including a total of 11,801 patients with COVID‐19, including 1278 in the hypernatremia group and 10,523 in the normonatremia group. Meta‐analysis showed that hypernatremia was associated with mortality in patients with COVID‐19 [OR = 4.15, 95% CI (2.95–5.84), p =.002, I² = 66.7%] with a sensitivity of 0.36 [0.26, 0.48] and a specificity of 0.88 [0.83, 0.91]. The posterior probability of mortality was 42% in patients with COVID‐19 hypernatremia and 15% in patients who did not have COVID‐19 hypernatremia. Conclusion: According to available data, hypernatremia is associated with death in patients with COVID‐19. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the association between moderate to vigorous physical activity (MVPA), sedentary behavior, fruit and vegetable intake, and the risk of sarcopenia among older Chinese adults. Methods: This cross-sectional study enrolled 5418 older Chinese adults who participated in the Study on Global Aging and Adult Health (SAGE). Participants reported information about their physical activity, sedentary behavior, and dietary habits (fruit and vegetable intake). Sarcopenia was defined as the presence of low skeletal muscle mass and either a slow gait speed or weak handgrip strength. A multiple logistic regression model was employed to determine the relationship between MVPA, sedentary behavior, fruit and vegetable intake, and the risk of sarcopenia. Results: Only 32.63% of participants met all three recommendations (for MVPA, sedentary behavior, and fruit and vegetable intake). Compared with meeting none of the recommendations, meeting all three recommendations was associated with a lower risk of sarcopenia (OR = 0.63, 95% CI = 0.41–0.98). Moreover, meeting the recommendation for sufficient fruit and vegetable intake (OR = 0.69, 95% CI = 0.58–0.83), MVPA and fruit/vegetable intake (OR = 0.67, 95% CI = 0.52–0.86), and sedentary behavior and fruit/vegetable intake (OR = 0.69, 95% CI = 0.48–0.98) was associated with a lower risk of sarcopenia. Conclusion: Our findings indicate that in this large representative sample of older Chinese adults, meeting lifestyle recommendations for MVPA, sedentary behavior, and fruit and vegetable intake protected against sarcopenia. [ABSTRACT FROM AUTHOR]

The rhombohedral sodium manganese hexacyanoferrate (MnHCF) only containing cheap Fe and Mn metals was regarded as a scalable, low‐cost, and high‐energy cathode material for Na‐ion batteries. However, the unexpected Jahn‐teller effect and significant phase transformation would cause Mn dissolution and anisotropic volume change, thus leading to capacity loss and structural instability. Here we report a simple room‐temperature route to construct a magical CoxB skin on the surface of MnHCF. Benefited from the complete coverage and the buffer effect of CoxB layer, the modified MnHCF cathode exhibits suppressed Mn dissolution and reduced intergranular cracks inside particles, thereby demonstrating thousands‐cycle level cycling lifespan. By comparing two key parameters in the real energy world, i.e. cost per kilowatt‐hours and cost per cycle‐life, our developed CoxB coated MnHCF cathode demonstrates more competitive application potential than the benchmarking LiFePO4 for Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Oxidation evolutions of structure, porosity and reactivity properties of four model carbons (PU, S160, N330 and R250) with different initial reactivity were studied. Results showed that changes in the porosity and nanostructure properties instead of initial properties significantly affected the soot reactivity during the soot oxidation process. Two high-reactivity soot surrogate samples, i.e., PU and S160, initially presented turbostratic disordered crystallites, resulting in higher reactivity at the early oxidation stage. Oxidation mainly proceeded inwardly in a peeling fashion, and more disordered internal crystallites were exposed after oxidized, slightly increasing the reactivity of PU and S160. Two low reactivity soot surrogate samples, i.e., N330 and R250, initially exhibited the typical core–shell structure. The oxidation rates of N330 and R250 were lower than that of PU and S160 due to more ordered exterior crystallites and less surface oxygen content at the early oxidation stage. Once oxygen penetrated the particle core, many pores were generated. Next, the particle became hollow through internal burning of the more reactive internal carbon at the late oxidation stage. After 40% burnoff, these hollow structures promoted oxidation in both outward and inward directions. Therefore, oxidation rates of N330 and R250 significantly increased. Oxidation evolutions of structure, porosity and reactivity properties of soot were performed. Porosity and nanostructure properties dominated the soot reactivity during oxidation process. Partial oxidation led to the reactivity increase for the soot with low initial reactivity properties. [ABSTRACT FROM AUTHOR]

Soot oxidation evolutions at various oxidation degrees under different O2-NO2 mixtures and temperatures were performed. Results indicated that the internal burning-out process represented by shell-like particles at 500 °C independent on NO2 concentration, while the development of hollow shells for the soot was suppressed with increasing the temperature. A tendency with soot toward a less ordered arrangement with short and defective graphene layers after oxidizing at 500 °C was also observed, which was suppressed with added NO2 and increasing temperature. Many carbon oxygen functionalities produced at 40% oxidation and the intensity of the peak gradually increased as the increase of the oxidation degree, while the increase of the peak intensity became less sensitive with added NO2 and increasing temperature. Abundant micropores and mesopores formed inside the particles during the soot oxidation process depending on oxidizer and temperature, micropores (smaller than 2 nm) were extensively generated at the early stages of the oxidation while mesopores increased sharply after 20% oxidation. The trends were correspondent to the oxidation modes with different oxidizer and temperature. The correlationship observation suggested that soot oxidation behavior was dependent on competing rates of reaction kinetics versus mass transport of oxidizer according to the oxidation evolution of surface and pore. Soot oxidation evolutions under different O2-NO2 mixtures and temperatures were performed Development of hollow shells for the soot was suppressed with increasing the temperature Abundant micropores and mesopores formed inside soot particles during oxidation process Oxidation behavior was dependent on competition of reaction kinetics versus mass transport [ABSTRACT FROM AUTHOR]

Particle volatility, size distribution, and parent and alkylated polycyclic aromatic hydrocarbon (PAH/alkyl-PAH) profiles during toluene pyrolysis in a flow reactor were studied. The experiments were conducted under three different gas residence times (0.2, 0.5 and 0.8 s) at temperatures from 950 to 1450 °C. Results showed that long residence times and high temperatures led to high particle mass concentrations, low particle volatility and a significant shift of particle size distribution to larger size. Total particle number concentrations exhibited a rise-then-fall trend (peaking at a critical temperature of 1050 °C) with increasing temperature, indicating that increasing temperature promoted a transition from nucleation to agglomeration and coagulation which dominated the particle size distributions. Among PAHs and alkyl-PAHs, those with 2–4 rings, presented the highest concentrations at 950 °C for 0.2 s. They appeared at 1050 °C for 0.5 and 0.8 s, consistent with the critical temperature of particle nucleation at long residence times (0.5 and 0.8 s). Particle peak number concentrations and total PAH mass concentrations exhibited consistent temperature dependence, indicating soot nucleation was highly related to PAH concentrations. According to the comprehensive observations in this study, low molecular mass PAHs instead of larger PAHs appear to be the precursors of soot formation during high temperature pyrolysis processes. [ABSTRACT FROM AUTHOR]

Electrically conductive cementitious composite (ECCC) can be utilized in traffic detection, structural health monitoring (SHM), and pavement deicing. Graphite is a popular conductive filler given its outstanding electrical resistance behavior, but its flat micro‐surface decreases the friction resistance, reducing mechanical strength. However, slag solids can substitute part of the graphite with their considerable conductivity and superior mechanical characteristics. In this research, 27 ECCC composites are developed incorporated by combined graphite powder (GP), blast furnace slag (GGBS), and steel slag (SS). Flexural, unconfined compressive strength (UCS) experiments, and resistance experiments with failure mode evaluations are carried out to explore the influence of proposed conductive fillers with different fractions. Results show the graphite strongly improves conductivity but dramatically reduces mechanical performance. Both steel slag and GGBS reduced the compressive and flexural strength after their replacement ratio exceeded 20%. Additionally, compared with GGBS, SS demonstrated a better influence on mechanical and conductive performance. A 15 wt% ratio of GGBS, 20 wt% of SS, and 4 wt% of GP are explored as the optimum design with 3.4 MPa of flexural strength, 36 MPa of compressive strength, and 7,779 Ω cm of resistance. Lastly, a microstructural investigation is conducted to explore the mechanical and conductive mechanism of ECCC. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiO) with high surface area was widely investigated in electrochemical applications. However, its use was largely confined to morphologies of particles and thin films. Here, we assembled NiO nanoparticles into mesoporous polyhedra with better active‐site exposure for oxygen evolution reaction (OER) catalysis. It needs an overpotential of 280 mV to drive 10 mA cm−2 in 1.0 M KOH, outperforming many reported transition‐metal oxides. Its activity can be mantained for at least 20 hours. High surface area of mesoporous polyhedra affirmed by Brunner‐Emmet‐Teller measurement contributes to the outstanding catalytic activity. Using one of the most abundant metal elements to constuct high‐performance OER catalysts will provide great convenience for industrial applications. [ABSTRACT FROM AUTHOR]

Precise prediction of PV power in the short term is crucial for maintaining power system stability and balance. However, the performance of conventional time series prediction models on short-term long series prediction is scarcely sufficient because of the stochastic and turbulent character of PV power data. This work suggests a PV short-term power forecast model based on weather type, AHA-VMD-MPE decomposition reconstruction, and improved Informer combination to tackle this issue. Firstly, a SUM-ApEn-K-mean++ multidimensional clustering method to group the dataset by weather conditions. Then an AHA-VMD-MPE decomposition model is proposed to decompose the historical power data Finally the Informer model is improved and the improved model is utilized to predict the PV power under various weather conditions. The model exhibits great accuracy and stability in short-term PV power prediction, as demonstrated by the experimental results, which were validated using measured data from many PV power plants. • A weather typing method based on SUM-ApEn-K-means++ has been proposed. • A sequence decomposition method based on AHA-VMD-MPE has been proposed. • The improved Informer model has been applied to short-term PV forecasting. • Validation has been performed on multiple time scales. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this systematic review is to quantitatively estimate (or invest) the impacts of sports-related concussions (SRCs) on cognitive performance among retired athletes more than 10 years after retirement. Methods: Six databases including (MEDLINE, Scopus, Web of Science, SPORTDiscus, CINAHL, and PsycArtilces) were employed to retrieve the related studies. Studies that evaluate the association between cognitive function and the SRC of retired athletes sustaining more than 10 years were included. Results: A total of 11 studies that included 792 participants (534 retired athletes with SRC) were identified. The results indicated that the retired athletes with SRCs, compared to the non-concussion group, had significant cognitive deficits in verbal memory (SMD = −0.29, 95% CI −0.59 to −0.02, I2 = 52.8%), delayed recall (SMD = −0.30, 95% CI –0.46 to 0.07, I2 = 27.9%), and attention (SMD = −0.33, 95% CI −0.59 to −0.06, I2 = 0%). Additionally, meta-regression demonstrated that the period of time between testing and the last concussion is significantly associated with reduced verbal memory (β = −0.03681, p = 0.03), and increasing age is significantly associated with the verbal memory (β = −0.03767, p = 0.01), immediate recall (β = −0.08684, p = 0.02), and delay recall (β = −0.07432, p = 0.02). Conclusion: The retired athletes who suffered from SRCs during their playing career had declined cognitive performance in partial domains (immediate recall, visuospatial ability, and reaction time) later in life. [ABSTRACT FROM AUTHOR]

Prussian blue analogues (PBAs) are promising cathode candidates for aqueous Na ion batteries (ANIBs) considering their low-carbon and cost-effective features. However, it is still a huge challenge to achieve desirable energy density coupled with long cycle life due to inherent Na defects in PBAs and the unstable solid-electrolyte interphase (SEI) layer. Herein, we design Na 2 C 4 O 4 additives as sodium supplements to compensate for Na defects in PBAs, while utilizing the CO 2 products decomposed from Na 2 C 4 O 4 to construct a robust SEI layer containing Na 2 CO 3 species. As proof of concept, our building of full ANIBs using iron-based PBAs and NaTi 2 (PO 4 ) 3 anode with an appropriate amount of Na 2 C 4 O 4 enable a reversible capacity of ∼144 mA h g -1 at 0.2 C and an excellent cycling stability of 15,000 cycles with 85% retention at 10 C. The proposed concept is further extended to the manganese-based PBA ANIBs to deliver an energy density of 92 W h kg -1 with improved cycling stability.