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IntroductionThe association between the residential environment and emotional wellbeing (EWB) in older adults has received extensive attention from gerontologists, especially during the COVID-19 pandemic; however, the mediating mechanism of how residential environment affects emotional wellbeing has not been fully explored. This study examined the effects of the residential environment on EWB and the mediating role of health lifestyle.MethodsThis study analyzed the survey data of 493 rural and 515 urban older adults from 2021 Chinese General Social Survey. General linear regression and structural equation models were used to examine the effects of residential environment and health lifestyle.ResultsUrban participants exhibited clear advantages in EWB, residential environment, and physical activity. Residential environment significantly affected the EWB of older adults, and health lifestyle played a mediating role in this relationship. The residential environment and health lifestyle did not significantly affect EWB in rural participants.DiscussionThis study revealed differences in the effects of health lifestyles and residential environments on EWB among older adults in rural and urban settings in China. This study provided empirical evidence of mental health disparities between older rural and urban Chinese residents.

This article reviews the application of the Reactive Molecular Dynamics (ReaxFF-MD) method in the field of insulating oil. It introduces the commonly used methods for constructing models of insulating oil and oil-paper, summarizes the pyrolysis mechanisms and influencing factors of insulating oil, analyzes the performance differences and advantages of different types of insulating oil, discusses the interactions and coupling effects in the oil-paper system. The paper points out the current status and existing issues in this field, providing a reference for further theoretical and experimental research.

At present, the alkylbenzene insulation oil for submarine cables of 220kV and above in China relies on imports, which poses high maintenance costs and supply interruption risks. Nano modified insulating oil has excellent electrical properties and broad application prospects in power systems. Therefore, nano SiO2 modified insulating oil was prepared, and the effects of APTES modified and unmodified nano SiO2 on the viscosity, breakdown voltage, and dielectric loss factor of the insulating oil were compared. The results showed that the viscosity of alkylbenzene insulating oil did not change significantly after the addition of nanoparticles, which met the operating standards for submarine cable oil; The breakdown voltage of the modified nano insulating oil has significantly increased, with a breakdown voltage of 0.12g/L being the highest. The breakdown voltage of the unmodified nano insulating oil has significantly decreased. The dielectric loss factors of modified and unmodified nano insulating oils do not vary significantly. This article provides theoretical and practical references for the domestic substitution research of submarine cable insulation oil.

Oil-filled submarine cables have come to dominate the reliable delivery of electrical power today, but oil leakage still remain a challenge. This work focuses on the exploring of spill behavior of dodecylbenzene (DDB) after leakage and the detection of DDB. Static and dynamic spill model were established to study the spreading and migration behavior of underwater DDB. In still water, the spilled oil droplets can quickly reach the uniform floating speed of 0.13 m s-1 with no significant change under different oil spill rates. DDB can be dispersed as small droplets in seawater, which the diameter of DDB droplets increased from 60 nm to 200 nm with the increase of the concentration from 10 ppm to 1000 ppm. This study suggests a research basis for finding the leakage point of submarine cables, and explores the way for detection of DDB.

The release behavior of sulfur during coal gasification was studied in a bench-scale self-heated circulating fluidized bed gasifier. With the increase of the O2/C molar ratio, gasification temperature increases, which promotes sulfur release rate and the formation of H2S. The conversion reaction between H2S and COS is far from equilibrium and the yield of COS is excessive. Under the same molar ratio of O2/C, the increase of coal feeding rate can elevate the gasification temperature, promote the release of sulfur and the transformation of gaseous sulfur to H2S.

Two kinds of high alkali and alkaline earth metal (AAEM) lignite (TTc and ZDc) were used as fuels, and three atmospheres of CO2, CO/CO2, and H2O (g) were used in the horizontal tube furnace experiments to simulate the gasification conditions in different parts of the boilers. The relevant thermodynamic calculations on the atmospheres and ash compositions were conducted in FactSage 7.2. The results show that both two coals have a high risk of slagging. Decreasing the relative content of SiO2 or increasing the relative content of Al2O3 can increase the ash fusion temperatures (AFTs) of TTc; increasing the relative content of CaO can increase the AFTs of ZDc. Besides, it is not recommended to adjust the relative content of Fe2O3. The proportion of the liquid phase of ZDc ash in CO/CO2 atmosphere is much higher than that of CO2 and H2O (g) in a typical circulating fluidized bed (CFB) gasification temperature interval, while the generation of liquid phase of TTc ash is less affected by atmospheres. The bottom of boilers is the most severe slagging zone, and purging with H2O (g) is a good way to alleviate the low-temperature slagging of the return feeder.

Along with the increasingly strict environmental regulation and the willingness to rapidly promote gasoline vapor recovery management, the development of technology and equipment for gasoline vapor recovery industry grows faster, and the demand for relevant technical standards is also growing. Based on the domestic and foreign development situation of gasoline vapor recovery technology and standard, this article analyzes necessity and urgency of the general technical standards for development of China’s vapor recovery unit, and then it introduces the main technical content of the national standard GB/T 35579-2017 General Specifications of Gasoline Vapor Recovery Unit”, and provides some advices to refine the related technical standards.

In order to investigate the galvanic corrosion of the connection between ductile cast iron and H62 brass water pipe in tap water supply network, electrochemical noise (EN), EDS, SEM and other methods were used to investigate the galvanic corrosion current, corrosion morphology and corrosion product composition of ductile cast iron /H62 brass electrode at different temperatures (0 ℃, 25 ℃, 40 ℃) and the specific surface area ratios of anode and cathode (Sc ∶Sa ＝1 ∶1、2 ∶1、4 ∶1) under the condition of simulated acidic industrial atmospheric corrosion.Results showed that when the nodular cast iron/H62 brass electrode was coupled, the nodular cast iron served as the anode, and the galvanic corrosion current density was 3.46 times that of its self-corrosion process.The anode corrosion of couple pair was intensified with the increase of temperature.With the increase of Sc ∶Sa, the galvanic corrosion current density increased.Furthermore, the Ig-t and Eg-t spectra of electrochemical noise revealed that the change in charge when the anode protection film of the electric couple pair was damaged and pitting occurred.Hence, the galvanic effect promoted the occurrence of pitting corrosion in anode ductile iron.

For investigating the microbial corrosion behavior of water supply pipelines in thermal power plants using regenerated water as the water source, a circular biofilm hanging plate reactor was used to dynamically simulate the operation status of the regenerated water pipeline. The influence process and mechanism of iron bacteria(IOB), sulfate reducing bacteria(SRB) and their mixture on the corrosion of Q235 steel were studied by measuring the pH value and conductivity of the solution, weight loss of the specimen, electrochemical parameters(such as redox potential, polarization curve, AC impedance), bacterial count, and combining SEM, EDS, XRD and other methods. Results showed that the number of two types of bacteria increased over time, and the pH value of the regenerated water first decreased and then increased, while the conductivity steadily increased. Furthermore, the number of bacteria in the environment was positively correlated with the corrosion rate of pipes at this time, and SRB were the main bacterial species that affected microbial corrosion. Through EDS and XRD analysis, it was found that the main components of corrosion products varied in different environments: the corrosion products during IOB process were mainly FeOOH, with a small amount of Fe2O3 and Fe3O4; the main corrosion products during SRB process were iron oxide and iron sulfide; When SRB+IOB coexisted, the main corrosion products were Fe2O3, Fe3O4 and FeS. Besides, the microbial film and corrosion products generated on the surface of the pipeline in the early stage would inhibit the corrosion of Q235. In the later stage, the deactivation of the microbial film and the detachment of the covered corrosion products would accelerate the corrosion.