Shizuishan City Research Articles

SPA-Based Methods for the Quantitative Estimation of the Soil Salt Content in Saline-Alkali Land from Field Spectroscopy Data: A Case Study from the Yellow River Irrigation Regions

The problem of soil salinization has always been a global problem involving resource, environmental, and ecological issues, and is closely related to the sustainable development of the social economy. Remote sensing provides an effective technical means for soil salinity identification and quantification research. This study focused on the estimation of the soil salt content in saline-alkali soils and applied the Successive Projections Algorithm (SPA) method to the estimation model; twelve spectral forms were applied in the estimation model of the spectra and soil salt content. Regression modeling was performed using the Partial Least Squares Regression (PLSR) method. Proximal-field spectral measurements data and soil samples were collected in the Yellow River Irrigation regions of Shizuishan City. A total of 60 samples were collected. The results showed that application of the SPA method improved the modeled determination coefficient (R2) and the ratio of performance to deviation (RPD), and reduced the modeled root mean square error (RMSE) and the percentage root mean square error (RMSE%); the maximum value of R2 increased by 0.22, the maximum value of RPD increased by 0.97, the maximum value of the RMSE decreased by 0.098 and the maximum value of the RMSE% decreased by 8.52%. The SPA–PLSR model, based on the first derivative of reflectivity (FD), the FD–SPA–PLSR model, showed the best results, with an R2 value of 0.89, an RPD value of 2.72, an RMSE value of 0.177, and RMSE% value of 11.81%. The results of this study demonstrated the applicability of the SPA method in the estimation of soil salinity, by using field spectroscopy data. The study provided a reference for a subsequent study of the hyperspectral estimation of soil salinity, and the proximal sensing data from a low distance, in this study, could provide detailed data for use in future remote sensing studies.

Contrastive Study of the Circular Economy of Coal Resource City Based on Ecological Efficiency and C Model

Abstract: Being a developing country, the evaluation of Chinese circular economy should have its particular criterion that suits for specific national conditions. With the growth of economy, Chinese environmental loads should be permitted to increase at an appropriate speed. Based on this concept, this paper divides the process of evaluation into two parts which include evaluation of development level and evaluation of development performance. Firstly, this paper sets up a reference system which includes Zaozhuang City of Shandong Province, Jiaozuo City of Henan province, Shizuishan City of Ningxia Hui Autonomous Region and China that is regarded as a region respectively, analyzes the development level of circular economy of coal resource cities based on the evaluation indicator of ecological efficiency, and puts forward the future direction of circular economy of coal resource cities. Secondly, based on C Model of Circular Economy, this paper constructs the measurement model of development performance in...

Assessment of the industrial circular economy in Shizuishan City

Assessment of the industrial circular economy in Shizuishan City

Thermo-economic Optimization of Solar–Coal Hybrid Systems

In this paper, an economic optimization of the solar multiple for the solar-coal hybrid systems was presented. The solar heat at approximately 300°C was used to preheat the feed water before entering the boiler in the typical coal-fired power plants. Three different unit scale coal-fired power plants have been considered, with the different parameters in the power block and different solar field sizes. Thermal performance for each solar power plant has been featured, both at design and off-design conditions under the climatic conditions of Shizuishan City. The economic assessments were then performed. The costs and payback period of each configuration with different steam extraction replaced were compared, using the well-established cost-estimating methodology. The levelized cost of energy (LCOE) for each case is calculated, yielding a minimum LCOE value for a certain solar multiple value within the range considered.

Hydrochemical characterization of drinking groundwater with special reference to fluoride in an arid area of China and the control of aquifer leakage on its concentrations

The objective of the study is to determine the distribution and origin of fluoride in two confined aquifers within the depth of 80–240 m (mid-deep confined aquifers) in Shizuishan City, an arid area in Northwest China. Based on geological and hydrogeological conditions, the distribution patterns of fluoride in the two confined aquifers were studied. Correlation analysis was used to reveal the mechanisms and reactions influencing the groundwater chemistry. The control of aquifer leakage induced by intense groundwater abstraction on fluoride concentrations was also discussed. The results show that the concentration of F− in some locations of the study area is beyond the limit of the Standards for Drinking Water Quality of China. Correlation analysis shows that the major reactions occurring in the confined aquifers are dissolution of gypsum, fluorite and halite, and precipitation of calcite and dolomite. Groundwater leakage from shallow aquifers is also responsible for the elevation of fluoride in mid-deep confined aquifers. The research is a scientific basis for the rational development and utilization of groundwater in this area, and it may be referenced by international scholars for similar research in other parts of the world.

Preparation of Xonotlite Nano-Fibres Using the Silica Source from Coal Fly Ash and Ca(OH)<sub>2</sub>

Extracting aluminum oxide from high-alumina coal fly ash are significant to make up for the inadequacy of bauxite resource in China. How to comprehensively utilize silica components in coal fly ash is a key technical question in industrialization for extracting of alumina from coal fly ash. Desilication of coal fly ash (CFA) and preparation of xonotlite were studied using the silica-rich solution from the CFA as silica source and calcium oxide as calcium source respectively. The CFA is from a power plant at Shizuishan city in Ningxia, China. Xonotlite was successfully prepared by a series processes including predesilication, hydro-thermal synthesis. The experimental results indicated that SiO2in the coal fly ash changed into NaSiO3after the coal fly ash was treated by desilication using NaOH solution. Hydrated calcium silicate was obtained from the reaction of the solutions produced by desilication and Ca (OH)2at the condition of Ca/Si (mol)=1, T=160°Cand t=1h. Xonotlite was synthesized by the hydrated calcium silicate using the hydrothermal temperature of 260°C for 2 hours. Keywords: Coal Fly Ash, Pre-desilication, alkali Hydrothermally-treated, Xonotlite nanofibres

Detection of Coal Fire Dynamics and Propagation Direction from Multi-Temporal Nighttime Landsat SWIR and TIR Data: A Case Study on the Rujigou Coalfield, Northwest (NW) China

Coal fires are common and serious phenomena in most coal-producing countries in the world. Coal fires not only burn valuable non-renewable coal reserves but also severely affect the local and global environment. The Rujigou coalfield in Shizuishan City, Ningxia, NW China, is well known for being a storehouse of anthracite coal. This coalfield is also known for having more coal fires than most other coalfields in China. In this study, an attempt was made to study the dynamics of coal fires in the Rujigou coalfield, from 2001 to 2007, using multi-temporal nighttime Landsat data. The multi-temporal nighttime short wave infrared (SWIR) data sets based on a fixed thresholding technique were used to detect and monitor the surface coal fires and the nighttime enhanced thematic mapper (ETM+) thermal infrared (TIR) data sets, based on a dynamic thresholding technique, were used to identify the thermal anomalies related to subsurface coal fires. By validating the coal fires identified in the nighttime satellite data and the coal fires extracted from daytime satellite data with the coal fire map (CFM) manufactured by field survey, we found that the results from the daytime satellite data had higher omission and commission errors than the results from the nighttime satellite data. Then, two aspects of coal fire dynamics were analyzed: first, a quantitative analysis of the spatial changes in the extent of coal fires was conducted and the results showed that, from 2001 to 2007, the spatial extent of coal fires increased greatly to an annual average area of 0.167 km2; second, the spreading direction and propagation of coal fires was analyzed and predicted from 2001 to 2007, and these results showed that the coal fires generally spread towards the north or northeast, but also spread in some places toward the east.

Epidemiological analysis of new cases of pneumoconiosis in Ningxia Hui Autonomous Region, China from 2006 to 2010

To investigate the epidemiological characteristics of pneumoconiosis in Ningxia Hui Autonomous Region, China from 2006 to 2009. Statistical analysis was performed on the types, populations, ages, and geographic distribution of the pneumoconiosis cases in Ningxia from 2006 to 2010, as reported in China Information System for Diseases Control and Prevention. A total of 625 new cases of pneumoconiosis (4 death cases) occurred throughout Ningxia from 2006 to 2010. Of the new cases, 538 (86.1%) suffered stage I pneumoconiosis, 70 (11.2%) stage II pneumoconiosis, and 17 (2.72%) stage III pneumoconiosis. Silicosis and coal-workers' pneumoconiosis were the dominant types of pneumoconiosis, accounting for 97.44% (609/625) of all cases. Of the 625 cases, 557 (89.12%) were distributed in Shizuishan City, and 563 (90.08%) were engaged in coal and metallurgical industries. Most cases were in the 35-year-old group and 45-year-old group, and the lengths of dust-exposed service mostly ranged from 10 to 29 years. In Ningxia, pneumoconiosis control should focus in the state-owned, middle-sized coal enterprises in Shizuishan City. Health surveillance should be enhanced in the workers with more than 10 years of dust-exposed service or aged more than 35 years, so as to reduce the incidence of occupational diseases.

Spatial Diffusion Model Analysis and Trend of Shizuishan City

The urban expansion direction and mode of Shizuishan City is addressed based on GIS and improved spatial diffusion model-replacing the spatial straight distance with cost weighted distance. This paper divides its spatial expansion into four cases: zero resistance, resistance, incomplete barrier and isolation. The diffusion model of urban space in terms of the new understanding of the resistance barrier in the spatial diffusion process is discussed. Then, this paper puts forward new trends of spatial development. The results reveal that Dawukou city area and Pingluo city, and Wuhai city and Huinong district form the coordination development tendency.

Global curve-fitting for determining the hydrogeological parameters of leaky confined aquifers by transient flow pumping test

Proper management of groundwater resources requires an accurate evaluation of the parameters (hydraulic properties) that control the movement and storage of groundwater. Hydrogeological parameters are the basis of groundwater evaluation, modeling, and management and so on. A global curve-fitting method incorporating pumping test data and water table recovery data was introduced in the present study. The principal and procedures of the method were elucidated in detail. The drawdown and recovery data from two sets of transient flow pumping test conducted in no. 2 water source site of Shizuishan city were used to verify the calculation accuracy of the proposed method. The hydrogeological parameters were also estimated with traditional type curve-fitting method on the basis of formula derived by Hantush and Jacob. The hydrogeological parameters calculated by the two methods were compared and the results show that the parameters obtained by the global curve-fitting method are a little bigger than but very close to those obtained by the traditional type curve-fitting method. The proposed method which possesses three major advantages is feasible and reliable in aquifer parameter identification. A comparative study on various methods for parameter identification is required and expected in future study.

Epidemiological analysis of human brucellosis in Ningxia from 2004 to 2009

Objective To learn the prevalence and trends of Brucella disease in Ningxia, in order to provide scientific basis for effective control of the disease. Methods Data of Brucella cases reported through city network from 2004 to 2009 in Yinchuan city, Shizuishan city, Wuzhong city, Guyuan city and Zhongwei city of Ningxia were reviewed and retrospectively analyzed. The data included demographic characteristics, treatment conditions and medical history so on related information. Analytical indicators include reported incidence;with patients' gender, age, regional distribution, urban and rural distribution;become chronic and associated factors;distribution of the cases reporting unit and so on. Results From 2004 to 2009, Ningxia had reported 349 cases of Brucellosis, no deaths, the annual incidence rates reported were 0.017/10 million, 0.543/10 million, 0.151/101 (295/54);The proportion of 34- to 40-year-old age group was higher than other age groups(27.5%, 96/349);Occupational distribution of patients was mainly farmers and herdsmen(70.2% ,245/349), in regional distribution of the patients, the highest percentage was Wuzhong city(61.9%,216/349), followed by Yinchuan city(22.9%,80/349);The proportion of patients in rural areas(97.4% ,340/349) was higher than urban(2.6% ,9/349);the proportion of patients converted to chronic was 11.2% (39/349). With age, the chance of patients converted to chronic was in a decreasing trend(odds ratio was 0.966);cases reported by Centre for Disease Control and Prevention accounted for 74.8%(261/349), by hospital accounted for 25.2%(88/349). Conclusions The reported incidence of Brucellosis in Ningxia is in a rapid upward trend year by year, the patients is mainly young men, the rate of converted to chronic is higher and the ability of hospital in founding and reporting of the cases is weaker.Comprehensive measures should be taken to increase funding, strengthen monitoring, and continuously improve the level of awareness and diagnosis of medical personnel for further strengthen the prevention and control of Brucellosis. Key words: Brucellosis; Epidemiology; Data collection