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By adding strong oxidizing ferrihydrite (amorphous) and weakly oxidizing but conductive magnetite (crystalline) to the anaerobic digestion system of waste cellar mud, the changes of Fe (II), organic matter and microbial community structure were investigated, and the effects of different types of Fe (III) minerals on anaerobic digestion of cellar sludge were explored. The results showed that the iron reducing bacteria were enriched in the ferrihydrite group, and the Fe(II) content increased rapidly to 900 mg/L on the twelfth day, indicating that the dissimilatory iron reduction of the ferrihydrite occurred. The chemical oxygen demand (COD) removal amounts in the ferrihydrite and magnetite groups were 16.1% and 4.9% higher than that in the control group respectively, indicating that the ferrihydrite and magnetite both promoted the removal of organic matter. The magnetite group enriched Geobacter and Methanosarcina, which promoted direct interspecific electron transport(DIET), increasing methane production by 23.4%, while the dissimilatory iron reduction of ferrihydrite inhibited methanogenesis and reduced methane production by 32.2%. [ABSTRACT FROM AUTHOR]

Eco-routing aims to provide fuel-efficient paths to help travellers make route choice decisions in the road network. Most eco-routing algorithms build on a deterministic assumption about link fuel consumption. However, link fuel consumption in real road networks is highly stochastic caused by travel speed variations. This study investigates the eco-routing problem by explicitly considering uncertainties of travel time and fuel consumption. A stochastic fuel consumption formula to estimate fuel consumption distributions caused by travel speed variations is proposed. A bi-objective reliable eco-routing model is developed by minimizing the travel time budget and fuel consumption budget simultaneously while satisfying given constraints on travel time reliability and fuel consumption reliability. An efficient reliable path ranking algorithm is developed to solve the formulated model exactly. A comprehensive case study using real data from Hong Kong is presented to demonstrate the applicability of the proposed model and algorithm. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the functional significance of 18F-labeled fibroblast activation protein inhibitor (18F-FAPI) activity in hypertrophic cardiomyopathy (HCM) by comparison with cardiac magnetic resonance feature-tracking (CMR-FT) strain analysis. Methods: A total of 49 HCM patients were included in this study. Two independent control groups of healthy participants with a matched age and sex to the HCM patients were also enrolled. Left ventricular (LV) 18F-FAPI activity was analyzed for extent (FAPI%) and intensity (maximum target-to-background ratio, TBRmax). The CMR tissue characterization parameters of the LV included late gadolinium enhancement, native T1 value, and extracellular volume fraction. LV strain analysis was performed in radial, circumferential, and longitudinal peak strains (PS). Results: Intense LV myocardial 18F-FAPI uptake was observed in HCM patients, whereas no obvious uptake was detected in healthy participants (median TBRmax, 9.1 vs. 1.2, p < 0.001). The strain parameters of HCM patients, compared with healthy participants, were significantly impaired (mean radial PS, 23.5 vs. 36.0, mean circumferential PS, −14.5 vs. −20.0, and mean longitudinal PS, −9.9 vs. −16.0, all p < 0.001). At segmental levels, there was a moderate correlation between 18F-FAPI activity and strain parameters. The number of positive 18F-FAPI uptake segments (n = 653) was higher than that of hypertrophic segments (n = 190) and positive CMR tissue characterization segments (n = 525) (all p < 0.001). In segments with negative CMR tissue characterization findings, the strain capacity of positive 18F-FAPI uptake segments was lower than that of negative 18F-FAPI uptake segments (median radial PS, 30.5 vs. 36.1, p = 0.026 and median circumferential PS, −18.4 vs. −19.7, p = 0.041). Conclusion: 18F-FAPI imaging can partially reflect the potential strain reduction in HCM patients. 18F-FAPI imaging detects more involved myocardium than CMR tissue characterization techniques, and the additionally identified myocardium has impaired strain capacity. [ABSTRACT FROM AUTHOR]

Zinc sulfide (ZnS) is a promising anode material for lithium-ion batteries (LIBs) because of its high theoretical capacity, abundance, cost-effectiveness, and environmental friendliness. Herein, a hydrangea-like ZnS-carbon composite (ZnS-NC) is synthesized through the hydrothermal method and subsequent pyrolysis of a supramolecular precursor guanosine. The resulting composite comprises ultrafine ZnS nanoparticles firmly stabilized on a nitrogen-doped carbon matrix, featuring mesoporous channels and high surface areas. When utilized as an anode material for LIBs, the initial discharge specific capacity of the ZnS-NC electrode reaches an impressive value of 944 mA h g−1 at 1.0 A g−1, and even after 450 cycles, it maintains a reversible capacity of 597 mA h g−1. Compared with pure ZnS, the ZnS-NC composite exhibits significantly improved rate performance and cycling stability. This enhancement in Li-storage performance can be attributed to a synergistic effect within the ZnS-NC composite, which arises from the large exposed active site area, efficient ion/electron transfer, and strong interaction between the ZnS nanoparticles and the carbon framework. Overall, this work presents an eco-friendly approach for developing metal sulfide-carbon composites with exceptional potential for energy storage applications. [ABSTRACT FROM AUTHOR]

To reduce the mining of high-grade magnesite and solve the environmental pollution caused by magnesite tailings, magnesite tailings were used to produce MgO expansion agent (MEA), and a detailed study of its performance was carried out in this study. Firstly, the effects of different calcination times on the calcination products, the specific surface area, and the activity of MEA were analyzed. Then, the MEA produced by calcinating at 950 °C for 1 h was taken as the research object, and the effects of its content on the expansion performance, compressive strength, and flexural strength of the mortar were studied. The results showed that the decomposition of magnesite tailings after high-temperature calcination produced MEA, and the longer the calcination time, the lower the activity. The calcined tailings could compensate for the shrinkage of the mortar, and the expansion increased with the increase in curing temperature. What is more, when the content was less than 8%, the hydration of MEA filled the pores and improved the compactness, so the strength of the mortar increased with the increase in the expansion agent content. When the dosage was greater than 8%, excessive expansion increased the porosity, causing harmful expansion of the mortar and damaging its integrity, leading to a decrease in strength. Fly ash reduced the expansion of mortar, and after adding 30% fly ash, the expansion decreased by 20.0–36.1%, and the ability to suppress expansion decreased with the increase in curing temperature. [ABSTRACT FROM AUTHOR]