Studying on Alloying Elements, Phases, Microstructure and Texture in FH36 Ship Plate Steel.

This study used simulation software and experiments to analyze the microstructure and texture of FH36 ship plate steel at different thicknesses and temperatures. The austenite phase transformed into ferrite phase at 830 °C and MC and M7C3 phases precipitated at 1150 °C and 543 °C, respectively. At room temperature, the microstructure at the surface and 1/4 thickness consisted of polygonal ferrite, acicular ferrite and granular bainite, while the 1/2 thickness had less acicular ferrite and granular bainite. The texture components were mainly {111}<110> and {111}<112> at all thicknesses, but {001}<110> was stronger at 1/2 thickness. The grain size decreased gradually from 1/2 thickness to the surface, and the proportion of high-angle grain boundaries was significantly lower at the surface than at 1/4 and 1/2 thickness.

Development and application of a multi-centre cloud platform architecture for water environment management.

To promote the intelligent and accurate management of river basins, especially large basins which involve many catchments, it is highly required to develop a useful platform to effectively coordinate arithmetic resources and data, and simultaneously help to make decisions based on the real-time calculation. In this study, a multi-centre cloud platform architecture called 3L4C was constructed, which includes a Cloud-edge-terminal Layer (3L), data centre, model centre, control centre, and customer-service centre (4C). Data fusion technology and an air-land-water coupled model were constructed. Based on HTML5, JavaScript, and Java, an integrated water environment management platform was created and applied to the Three Gorges Reservoir Basin, China. The platform was tested and successfully used for automatic water quality prediction, water environment pollution analysis and control, early warning of abnormal water quality, and emergency water pollution incident evaluation. This platform quickly and accurately forecasts and perfectly displays past, present and future state of the water environment, and offers beneficial support for management decisions in various water environment departments.

On the coordination in diversity between water environmental capacity and regional development in the Three Gorges Reservoir area.

Water environment capacity has drew the attention of policymakers and stakeholders to sustainable development, and its dynamic changes are ultimately impacted by population, capital, and industrial clusters under regional development. Previous research, however, has not been able to completely comprehend it. In this paper, the authors use the Coupling Coordination Degree model and the Geodetector model to study the temporal and spatial evolution of water environment capacity and its driving mechanism based on regional development represented by regional function including urbanization function, ecological function, and agricultural function using the Three Gorges Reservoir area on county scale as a case study from 2000 to 2015. The results showed that (1) compared with 2000, 2005, and 2010, the water environment capacity of the whole reservoir area in 2015 was significantly improved. (2) The urban functions of each district and county are increasing in different years, and the dynamic changes of ecological and agricultural functions are obviously different. (3) The water environment capacity of districts and counties in the head area. There are significant disparities in the relationship between water environment capacity and regional function in various regions. Differences in water environment capacity are largely influenced by ecological function and the interaction driver of the proportion of agricultural function and urban function, which are typically the biggest of all the components. This suggests that regional development is a top priority in order to improve the operability of the water environmental capacity through more regulation, rules, and planning.

Spatial characteristics of nutrient budget on town scale in the Three Gorges Reservoir area, China.

Accurately quantifying nutrient budget is an essential step toward sustainable nutrient management in large watersheds increasingly disturbed by human activity. A town-scale nutrient budget framework based on the Soil and Water Assessment Tool was developed for 2010-2012 in the Three Gorges Reservoir area in China (TGRA). Moran's I spatial correlation test and Geodetector spatial heterogeneity test were employed to systematically analyze the spatial characteristics of the resulting nutrient budget. The Moran's I value of total nitrogen (TN) and total phosphorus (TP) gradually increased from input to output in the range of 0.091-0.232 and 0.102-0.484, respectively. Towns with higher TN and TP inputs were largely concentrated in the main urban area of Chongqing because of its high population density. By contrast, towns with higher TN and TP outputs were concentrated in the head of the TGRA. The Moran's I values of the TN and TP retention coefficients (R) were 0.433 and 0.524, respectively, demonstrating clear spatial consistency. Towns with a "High-high" spatial consistency pattern and positive R value were concentrated in the tail and hinterland, while those with a "Low-low" spatial consistency pattern and negative coefficient value were located mainly in the head of the TGRA. This phenomenon was mostly caused by differences in regional elevation, the normalized difference vegetation index, and soil erosion factor. The interaction effect between any two of these three factors on nutrient retention (Geodetector q-value) was greater than 60%. Therefore, future nutrient management should be based on a full understanding of regional biophysical conditions, especially in large areas. These findings provide a new perspective on fine nutrient management.

Spatial differentiation and driving mechanism of rural water security in typical "engineering water depletion" of karst mountainous area-A lesson of Guizhou, China.

Southwest China gets abundant rainfall, but in its rural areas, there is a severe shortage of water resources for irrigation and drinking. A case study was conducted in the Guizhou Province, which has the most concentrated karst distribution worldwide. The rural water security index was constructed, and Geodetector and ArcGIS were employed to systematically analyze the status quo, spatial differentiation, and driving mechanism of water security in rural areas of Guizhou in 2016. The results showed that (1) there was obvious spatial variation in the rural water security index in the study area, with only 3.85% of areas being maximally safe, and 20.51%, 35.89%, 15.38%, and 24.36% being sub-optimally safe, moderately safe, unsafe, and extremely unsafe, respectively. The spatial distribution of the rural water security index, it generally coincides with a gradual decay from the economically developed areas to the periphery. The water security of the geographical environment is inferior to those of domestic water and water for agricultural production. (2) For Guizhou Province, economic and social factors, such as the disposable income of rural residents and the incidence of impoverishment, were critical factors influencing rural water security. The critical influencing factors vary greatly among prefectures; however, there are some common factors that affect rural water security, such as the incidence of impoverishment, the penetration rate of rural piped water, the percentage of primary industry, and the percentage of karst area. The maximum value of the interactive driver of the percentage of groundwater and the disposable income of rural residents was 0.812, indicating that the interaction between the high percentage of groundwater caused by karst development and the low disposable income of rural residents was the primary reason for the low rural water security. (3) Rural water security was largely influenced by poor socioeconomic development, resulting in a low level of security and the availability of public water facilities and domestic water in rural areas. Significant improvements in rural water security depend on ameliorating the water security of agricultural production and domestic water, rather than improving the geo-environmental conditions of water resources at extremely high costs.

The architecture and application of an automatic operational model system for basin scale water environment management and design making supporting.

An advanced framework for automatic water quality forecasting and water quality management design supporting was put forward. The system is designed as a flexible and extensible service-oriented architecture with data center, system control center, model center and client center. Two operational running modes, one for water environment automatic assessment and forecast and the other for situational analysis, were set to satisfy water quality management requirements. With loosely-coupled air-land-water numerical models, the weather, pollutants sources, hydrodynamic and water quality are automatically forecasted. According to philosophy of the framework, a one-stop platform with four different subsystems for the Three Gorges Reservoir Basin (TGRB) was developed and has been in operational running for more than two years. The system can accurately assessed, forecasted and perfectly displayed the current status and future character of TGRB in air, land and water environment.

Assessment on China's urbanization after the implementation of main functional areas planning.

China has implemented main functional areas planning (MFAP) since 2010, which is essential for improving the efficiency of land space utilization and achieving sustainable urban development. Quantitative assessments of the urban development levels (UDLs) at the county level across China after the implementation of MFAP have not been well-documented. In this study, a unified indicator system was developed, and the UDLs of 2850 counties in China after MFAP implementation were evaluated. The results showed that MFAP played a positive role in urban development in China. The UDLs in China generally increased but showed obvious spatial differences. The higher UDLs were mostly found in the counties in the five urban belts, which reflects the overall urban layout of China. The UDLs were generally low in the western counties in comparison with those in the eastern part of China. The differences in the UDLs from east to west were greater than those from north to south. Moreover, the differences in the UDLs presented a spatial agglomeration effect. This study could offer insight into the refinement of MFAP in China and sustainable urban development in developing countries.

Accurately early warning to water quality pollutant risk by mobile model system with optimization technology.

A fast and accurate water quality pollutant risk assessment and early warning system, which has great practical significance for decision making in accident management, is urgently needed for water protection and management. Based on a fast mobile early warning system named MEWSUB, this paper modified its framework to make it generate data more automatically and accurately. By adapting manning formula and particle swarm optimization (PSO) for parameters optimization, the accuracy of water quantity and water quality simulation results has been improved. The modified system was successfully applied in an antimony tailings dam leakage accident that happened in China. The coefficient of determination (R2) of the prediction result was higher than 0.9 and relative error (ree) was less than 0.1, which indicated that the accuracy of MEWSUB was high enough for realistic water quality pollutant risk early warning.

Assessment of debris inputs from land into the river in the Three Gorges Reservoir Area, China.

Riverine debris in the Three Gorges Reservoir Area (TGRA) poses a threat to electricity generation, ship navigation, and water environment. Quantifying riverine debris inputs from land into the river is a foundation for modeling of the transport and accumulation of floating debris on the water surface in the TGRA. However, this has not been researched to date. In this study, debris inputs from land into the river in the TGRA were assessed according to the response relationship between debris inputs and surface runoff. The land-based debris inputs in the TGRA were estimated using simulated surface runoff which was simulated by the Soil and Water Assessment Tool (SWAT) model. Results showed that 15.32 × 106 kg of land-based debris was inputted into the main channel of the TGRA in 2015 which accounted for 9.74% of total debris inputs (the monitoring data of river-sourced and land-sourced debris inputs was 157.27 × 106 kg). Debris inputs varied seasonally and peaked in the summer season (July to September). Compared with monthly measured data, the average relative errors in 2015 were below 30%. In addition, areas with higher debris pollution inputs were mainly located in the upper section of the TGRA, between the Tang River Basin and the Long River Basin. The proposed method was tested and determined to be reliable; thus, it can be used to quickly estimate debris inputs from land into the river by surface runoff of the outlets in a river basin. Moreover, this method provides new insight into the estimation of land-based debris inputs into rivers.