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The main objective of this study was to evaluate eight kinds of trace element pollutants in groundwater from a typical coal mine area, and carry out a corresponding health risk assessment for the local populace. To do this, 34 shallow groundwater (SG) samples and 18 mid-layer groundwater (MG) samples were collected from the Sulin mining area. To minimize the uncertainties in the health risk assessment, this paper relied on Monte Carlo simulations and sensitivity analysis. The results revealed that Sr and Mn contents exceeded their corresponding WHO (Guidelines for drinking water quality, 4th edn. Geneva, 2011) guidelines and Chinese groundwater standards (GB/T14848–2017), while the other analyzed trace elements remain below those threshold values. The calculated hazard quotient and hazard index values for adults from ingestion exposure to SG and MG were well below the threshold limit of 1. Probabilistic simulations further show that the total cancer risk value above the limit of 1 × 10−6 is 0% for SG and 29.39% for MG. Sensitivity analysis identified the Sr and Cr contents as the most relevant element variables affecting the probabilistic non-carcinogenic and carcinogenic risk values in the model, respectively.

Urban rivers play an important role in maintaining the urban aquatic ecological environment, and there are bound to be differences in the water environment quality and pollution sources due to different locations of urban rivers. Therefore, this paper selects the urban river (Tuo River) and the suburban river (Bian River) in Suzhou City, Anhui, China, as the research objects. Based on the understanding of the hydrogeochemical characteristics of these two rivers, the self-organizing map is used to identify the main control factors that affect the water quality of the two rivers. The results showed that both the Bian river and Tuo river were weakly alkaline. The average content of conventional ions in Tuo river is less than that of Bian river (except HCO3−); the water of Bian river was of Na–SO4–Cl type, and the water of Tuo river was mainly of Na–HCO3 type, with the minority was of Na–SO4–Cl type; Silicate weathering is an important source of conventional ions in the water of these two rivers; agricultural non-point source pollution is the main source of pollutants in Bian river, while Tuo river was mainly affected by natural factors, and human activities had little impact.

Fluoride groundwater pollution is a major challenge to ensuring a safe groundwater supply for the global community. This study emphasized mid-layer groundwater (MG) as the main water supply source in the Huaibei mining area, North China. A total of 74 groundwater samples were taken to determine the hydrochemistry, source provenance, driving forces of high-fluoride groundwater, and associated probabilistic health risk using Monte Carlo simulation. The fluoride concentration in 55.56 % of the MG samples exceeded the Chinese drinking water permissible limit of 1 mg/L. In addition, MG is characterized by the hydrochemical faces of HCO

Major ion and trace element concentrations in shallow groundwater of Linhuan coal-mining district, Northern Anhui Province, China, were analyzed to determine its hydrogeochemical characteristics and to assess drinking and irrigation water quality. The relative abundance of cations and anions was Na+ > Mg2+ > Ca2+ > K+, and HCO3− > SO42− > Cl− > NO3−, respectively. The concentrations of Na+, HCO3−, NO3−, and total dissolved solids (TDS), and the electric conductivity (EC) values in some samples were higher than the permissible limits of the Water Health Organization (WHO). Gibbs diagrams showed that rock weathering mainly controlled the major ion chemistry of the groundwater, and the first aquifer of this study area had a weak hydraulic connection with atmospheric precipitation. The calculated sodium percentage (%Na) and sodium adsorption ratio (SAR) revealed that the slight sodium and high salinity hazards needed to be controlled before irrigation. According to the fuzzy comprehensive assessment, the groundwater samples were classified into four categories. The results showed that 92.86% of the groundwater samples were suitable for drinking use. For human health, the NO3− and Mn levels in the groundwater should be reduced before drinking, and treatment of the high salinity hazards is required before irrigation.

To manage public health and make better use of groundwater resources, the concentration characteristics and a health risk assessment of eight heavy metals in shallow groundwater were studied. Besides this, this paper introduced triangular fuzzy numbers into the USEPA health risk assessment model to assess the health risk posed to local children and adults through different exposure pathways. The results showed that Mn levels exceeded the WHO’s guideline values of 100 µg/L with the proportion of 27.98% and Sr were over the health reference level (HRL) of 1500 µg/L with the proportion of 56.25%, while other heavy metals were below the corresponding standard. The results of the HRA showed that the non-carcinogenic risks from Sr and Mn in the district were relatively higher, while those from the remaining six heavy metals were relatively lower. All hazard index (HI) values did not exceed the safety level of 1 for either age group. The average carcinogenic risk from Cr was slightly higher than the acce...

The aim of the present study was to investigate the effects of endogenous H2S on the inflammatory response in kidneys following urine-derived sepsis-induced injury. A rabbit model of urine-derived sepsis was established by injecting Escherichia coli into the ligated ureter. Rabbits were randomly divided into the, control, sham, sepsis and DL-propargylglycine (PAG)-treated sepsis groups. The same surgical procedure except for the bacteria injection was performed for the sham group, while the control group was fed on normal diet without any additional treatments. The monitoring of vital signs, routine blood examinations and kidney function tests were performed prior to surgery and at 12, 24, 36 and 48 h following surgery. The serum H2S concentration and kidney cystathionine-γ-lyase (CSE) activity were determined following surgery. Pathological alterations were assessed by hematoxylin and eosin (H&E) staining, and the expression levels of inflammation-associated cytokines were detected by western blot analysis. The results demonstrated that rabbits in the sepsis and PAG groups exhibited a significant increase in rectal temperature, heart rate and respiratory rate following surgery when compared with the sham group; with the PAG group demonstrating the greatest increase. In addition, white cell counts and creatinine and urea nitrogen levels were significantly elevated following surgery in the sepsis and PAG groups when compared with the sham group. The serum H2S concentration and kidney CSE activity were significantly reduced in the sepsis group compared with the sham group, and a significant decrease in the levels of these factors were observed in the PAG group compared with the sepsis group. H&E staining indicated obvious structural abnormalities in kidney tissues in the sepsis group, which were exacerbated by PAG treatment. In addition, PAG treatment significantly increased the expression levels of nuclear factor-κB and interleukin-6, and decreased transforming growth factor-β1 expression when compared with the sepsis group. In conclusion, PAG significantly exacerbated urine-derived sepsis-induced kidney injury potentially via altering the expression of inflammation-associated cytokines.

Surface water is not only an important water supply to mining region but also the cause of severe water burst accidents in coal mines. In China, surface water is categorized as a major water hazard that has inflicted serious property losses and casualties not seen in the rest of the world. Based on the analysis of the distribution and characteristics of 47 major mining accidents caused by surface water in China coal mines, this paper summarizes the disaster-causing mechanism of surface water hazards in coal mines. Main research results are as follows: (1) coal mine accidents caused by surface water mainly occur in spring and summer with large rainfall; particularly in summer when 70% of such coal mine accidents took place, (2) natural water channels include valleys and gullies, surface tension fissures, water-conducting faults, and karst collapse caves in mountain areas; (3) artificial water channels include underground structures in abandoned mines (such as shafts and roadways), water-conducting cracks resulted from mining activities, and illegal mining of water and sand-resistant coal (rock) pillars. Through the analysis of engineering cases, this paper puts forward prevention and control measures of surface water hazards of coal mines. The results of this paper can be of reference to other countries tasked to treat surface water hazard while protecting surface water resources.

This paper describes an application framework for the spatial acquisition of electroencephalograph(EEG) electrodes, which includes camera group calibration and EEG electrode registration. We present a joint calibration method for a camera group including a 3D Time-of-Flight(ToF) camera and a CCD camera to align the 3D measurements with the color image correctly. Considering the characteristics of the 3D ToF camera, we have designed a 2.5D calibration plate with 100 holes for sensing depth information. In order to improve the accuracy of calibration, we propose a calibration scheme based on 3D point cloud instead of low resolution and large distortion depth image. Then we apply the calibration results to the extraction of the electrode position and optimize the extraction process to unify all the electrodes used for registration to the target coordinate system. The results show that the various methods we propose can improve the performance of the system.

Since 1990s, goaf water has become a frequent cause of water disaster in China coalmines, inflicting severe human casualties and huge economic losses. Based on the analysis of the goaf water disaster cases in China coalmines, this article put forward the theoretical and technological system of goaf water control, which include (1) the area and volume of goaf water are reasonably determined due to existence form of goaf water and geophysical prospecting results, (2)retaining sufficient water-resistant coal (rock) pillar to prevent goaf water inrush from adjacent and above, (3)grouting insecure or failure water-resistant coal (rock) pillar, and (4) draining goaf water using “fanned-out” normal drill and long-distance directional drill, and of all, draining goaf water through long-distance drill has been proved to be technically superior in engineering practices. The research results can be of reference to other coal-producing countries in similar geological conditions.

Palladium(II) p-oxoiminatophosphane complexes were Αbstract; Palladium(II) β-oxominatophosphane complexes were used as catalysts for the Sonogashira coupling reaction. In the presence of very low amounts of the complexes, various aryl iodides and bromides were efficiently coupled with phenylacetylene even at room temperature. Furthermore, the catalysts were also effective for the reactions of aryl chlorides. It is noteworthy that this catalyst system employed mild, efficient, aerobic, solvent-free, and copper-free conditions.

The immobilized N-heterocyclic carbene–Pd complex was readily prepared by reaction of silica gel-supported imidazolium chloride with Pd(OAc)2. The Pd complex exhibited excellent catalytic activity in the coupling reaction of aryl halides with arylboronic acid. The heterogeneous Pd catalyst was reusable as well as air-stable to allow easy use.

Chiral amino thioacetate ligands were prepared from the corresponding amino alcohols and used as catalysts for enantioselective aryl transfer reaction. The amino thioacetates were remarkably superior to the corresponding amino alcohols. Low catalyst loadings of only 1-2.5 mol % were sufficient to achieve excellent enantioselectivity as well as high conversion in short reaction time. The results reveal that the thioacetoxy moiety of the amino thioacetates has a surprisingly beneficial effect in enhancing the asymmetric induction.

Palladium(II) p-oxoiminatophosphane complexes were Αbstract; Palladium(II) β-oxominatophosphane complexes were used as catalysts for the Sonogashira coupling reaction. In the presence of very low amounts of the complexes, various aryl iodides and bromides were efficiently coupled with phenylacetylene even at room temperature. Furthermore, the catalysts were also effective for the reactions of aryl chlorides. It is noteworthy that this catalyst system employed mild, efficient, aerobic, solvent-free, and copper-free conditions.

Palladium acetate was encapsulated onto highly ordered mesoporous silica MCM-41 with the aid of ionic liquid. The immobilized Pd complex can efficiently catalyze Heck coupling reactions of activated and non-activated aryl halides with acrylates. The Pd catalyst exhibited remarkably high catalytic activity and outstanding stability. Moreover, the immobilized palladium acetate could be recycled at least six times without significant loss of activity.