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Dataset of Noninvasive beam diagnosis based on the TM010 mode Dataset of Noninvasive beam diagnosis based on the TM010 mode

The prediction of gas productivity and reservoir stability of natural gas hydrate (NGH) reservoirs plays a vital role in the exploitation of NGH. In this study, we developed a THMC (thermal-hydrodynamic-mechanical-chemical) numerical model for the simulation of gas production behavior and the reservoir response. The model can describe the phase change, multiphase flow in porous media, heat transfer, and deformation behavior during the exploitation of NGH reservoirs. Two different production scenarios were employed for the simulation: depressurization and depressurization coupled with CO2 exchange. The simulation results suggested that the injection of CO2 promotes the dissociation of NGH between the injection well and the production well compared with depressurization only. The cumulative production of gas and water increased by 27.88% and 2.90%, respectively, based on 2000 days of production simulation. In addition, the subsidence of the NGH reservoir was lower in the CO2 exchange case compared with the single depressurization case for the same amount of cumulative gas production. The simulation results suggested that CO2 exchange in NGH reservoirs alleviates the issue of reservoir subsidence during production and maintains good reservoir stability. The results of this study can be used to provide guidance on field production from marine NGH reservoirs.

Public engagement is essential for China to address climate change; however, few studies have explored how to encourage climate awareness among Chinese residents. The objective of this study is to explore the role of local extreme weather in advancing Chinese people's climate change awareness. Whether local extreme weather functions as an opportunity to trigger the public's interest in climate change across China and whether the local online information environment resonances with extreme weather by providing climate change news feeds have been examined by a combination of city-level meteorological warnings and search engine data. The results have verified that residents from 50 of the 360 cities show increasing concern for climate change when an extreme weather event occurs locally; however, only the online information environment of two cities echoes local extreme weather by providing more information about climate change or global warming. Correlations between extreme weather events such as heavy rain, an extreme weather event that has occurred in China, and climate change are underestimated. The effect of extreme cold events and snowfall on climate change awareness should also be noted more in China. This study suggests there is still a lot of room for improvement regarding both increasing and satisfying the public's pre-existing climate change-related concerns. A promising approach would be adopting climate change prevention and adaptation as a news report framework for extreme weather events.

Open circuit voltage (OCV) is an important characteristic parameter of lithium-ion batteries, which is used to analyze the changes of electronic energy in electrode materials, and to estimate battery state of charge (SOC) and manage the battery pack. Therefore, accurate OCV modeling is a great significance for lithium-ion battery management. In this paper, the characteristics of high-capacity lithium-ion batteries at different temperatures were considered, and the OCV-SOC characteristic curves at different temperatures were studied by modeling, exponential, polynomial, sum of sin functions, and Gaussian model fitting method with pulse test data. The parameters of fitting OCV-SOC curves by exponential model (n = 2), polynomial model (n = 3~7), sum of sin functions model (n = 3), and Gaussian model (n = 4) at temperatures of 45 °C, 25 °C, 0 °C, and −20°C are obtained, and the errors are analyzed. The experimental results show that the operating temperature of the battery influences the OCV-SOC characteristic significantly. Therefore, these factors need to be considered in order to increase the accuracy of the model and improve the accuracy of battery state estimation.

Abstract Plug-in electric vehicles (PEV) appears to have sales momentum in major personal vehicle markets but are still at the early market stage. Opportunities to accelerate PEV adoption can be discovered through comprehensive total cost of ownership (TCO) analysis. Understanding the cost-effective electric ranges of PEVs for consumers, manufacturers, and the society is critical for any discussion of PEV mass markets. This study expanded the traditional TCO approach by (1) fully considering heterogeneous consumer driving patterns, (2) quantifying the charging inconvenience and range anxiety cost of battery-electric vehicles (BEVs), and (3) monetizing both tangible and intangible PEV policies. Uncertainties were handled through Monte Carlo simulation. The results suggest that BEVs with an electric range of 250–350 km have the lowest TCO in cities with government-enacted purchase limitations, and internal combustion engine vehicles (ICEVs) have the lowest TCO in cities without purchase limitations, even when considering PEV subsidies. The lowest TCO for some consumer groups is obtained by BEVs with an electric range of 400–450 km, especially in northern China, where the weather is colder. The cost-effective all-electric range for BEVs in each city in 2025 will decrease due to improved battery performance in cold environments and an expanded charging infrastructure. Based on TCO, plug-in hybrid electric vehicles (PHEVs) are currently more suitable for drivers with a high average daily mileage or a large mileage variance. However, by 2025, BEVs with a long driving range may become a more cost-effective choice for these drivers.

The emission of condensable particulate matter (CPM) and its environmental impacts are arousing concern in China with the effective control of filter particulate matter (FPM). This study established an up-to-date and unit-based CPM emission inventory for industrial sectors and systematically evaluated the effects of CPM on primary and secondary PM2.5 in China. In 2020, the national CPM emissions total for industrial sectors was estimated to be 0.98 Tg with uncertainty from -49% to 66%, including 0.62 Tg of organic CPM (CPMorg) and 0.36 Tg of inorganic CPM (CPMin). Totals of 62%, 23% and 8% CPM were emitted from coal-fired power plants, coal-fired industrial boilers and sinter plants, respectively. By filling CPM emissions in PM2.5 simulation, the normalized mean bias (NMB) of model to observation was improved from -27% to -14% in East, North and Central China. The 4 μg/m3 PM2.5 concentration was attributed to CPM emissions in this region, accounting for 10% of observations. On "polluted" days (PM2.5>75 μg/m3), industrial CPM emissions can contribute 7 μg/m3 PM2.5 in North China. Therefore, China should focus on controlling CPM from coal combustion to ensure continuous air quality improvement.

Abstract The 5 MW nuclear heating reactor (NHR-5) is the first vessel type heating reactor in operation. Since November 1989 the 5 MW nuclear heating reactor has operated successfully for three years during the winter. A series of experiments and operation tests were carried out during the commissioning and operation periods. The main results of the experiments are given in this paper. It has been shown that the NHR-5 possesses excellent safety characteristics and a high operation availability.

AbstractA simple and low‐cost modification method was developed to improve the power generation performance of inexpensive semicoke electrode in microbial fuel cells (MFCs). After carbonization and activation with water vapor at 800–850 °C, the MFC with the activated coke (modified semicoke) anode produced a maximum power density of 74 W m−3, 17 W m−3, and 681 mW m−2 (normalized to anodic liquid volume, total reactor volume, and projected membrane surface area, respectively), which was 124 % higher than MFCs using a semicoke anode (33 W m−3, 8 W m−3, and 304 mW m−2). When they were used as biocathode materials, activated coke produced a maximum power density of 177 W m−3, 41 W m−3, and 1628 mW m−2 (normalized to cathodic liquid volume, total reactor volume, and projected membrane surface area, respectively), which was 211 % higher than that achieved by MFCs using a semicoke cathode (57 W m−3, 13 W m−3, and 524 mW m−2). A substantial increase was also noted in the conductivity, C/O mass ratio, and specific area for activated coke, which reduced the ohmic resistance, increased biomass density, and promoted electron transfer between bacteria and electrode surface. The activated coke anode also produced a higher Coulombic efficiency and chemical oxygen demand removal rate than the semicoke anode.