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Objective To explore the enrichment conditions and main controlling factors of shale gas in the Lower Wuerhe Formation of the Permian System in the Junggar Basin, the Lower Wuerhe Formation in the Dongdaohaizi Sag was selected as the research object. Methods Based on the data of outcrop, core, well logging, well-calibrated seismic reflections and the technologies of total organic carbon (TOC) content determination, whole-rock X-ray diffraction, gas adsorption (N2, CO2), the distribution characteristics, organic matter development characteristics, reservoir characteristics, and gas bearing characteristics of the Lower Wuerhe Formation shale were studied. Results The results show that: (1) The organic matter of the Lower Wuerhe Formation shale is dominated by Ⅱ2 and Ⅲ types and shows an average TOC content of 1.58%. The average vitrinite reflectance (Ro) of organic matter is 1.46%, which indicates the mature stage. The average thickness of the source rock is 75 m. Summarily, the source rock is good and has a high gas potential. The basin simulation results show an average shale gas content of 1.89 m3/t in the Lower Wuerhe Formation. (2) The pores and microfractures in shale reservoirs are highly developed, and gas is primarily adsorbed in micropores and mesopores. The average porosity and permeability are 6.10% and 0.27×10-3 μm2 respectively, which are favourable for shale gas accumulation. (3) The shale has a high clay mineral content, with an average of 29.6%, providing a significant specific surface area and enhancing the gas adsorption capacity of the shale. Additionally, the average brittle mineral content is 50.9%, indicating good frackability. (4) Moreover, the shale reservoir exhibits a relatively large pressure coefficient of 1.58, indicating the favourable conservation conditions. The analysis of the regional tectonic-sedimentary environment and geochemical parameters indicates that the main factors controlling shale gas accumulation in the Lower Wuerhe Formation of the Dongdaohaizi Sag are geochemical parameters and preservation conditions. The key factors influencing shale gas accumulation include the high thermal evolution maturity of organic matter, large shale thickness, high TOC content, and good preservation conditions. These conditions suggest that the favourable area for shale gas exploration and development in the Dongdaohaizi Sag is located in the northeastern slope area of the sag's abdomen. Conclusion The results of this research reveal the enrichment conditions and main controlling factors of shale gas in the Lower Wuerhe Formation in the Dongdaohaizi Sag, which has reference value for deep oil and gas exploration in the abdominal area of the Junggar Basin.

By using GC-ECD, the concentrations of organochlorine pesticides hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in the shellfish culture environment (sea water, sediments, and culture-shellfishes) in Xiamen sea area were analyzed, and the accumulation and degradation patterns of the HCH and DDT were preliminarily approached. In the sea area, there existed remarkable differences in the accumulation and degradation of HCH and DDT among different shellfish culture environments, being mostly associated with the habitation environment and physiological life habits of shellfish. The accumulated HCH isomers (Rx >1) were mainly &bgr;-HCH, &dgr;-HCH, and &ggr;-HCH, whereas the degraded HCH isomers (Rx <1) were mainly &agr;-HCH. The ratio of &agr;-HCH to &ggr;-HCH was less than or equal to 1. 0, suggesting that the HCH was come from industrial HCH and lindane, most of the HCH had remained in the culture environment for a longer time, and a small amount of lindane was imported. The DDT in the sea water was aerobically degraded, its main degradation product was DDE, and the ratios of (DDD+DDE) to DDTs (p,p-DDE+p,p- DDD+o,p-DDT+ p,p-DDT) was less than 0. 5, whereas the DDT in sediments and shellfishes was anaerobically degraded, its main degradation product was DDD, and the ratios of (DDD+DDE) to DDTs was greater than 0. 5, suggesting that there was a small amount of DDT newly imported in the sea water, and most DDT in sediments and shellfishes were already degraded and transformed into DDD and DDE. There were definite differences in the degradation rates of HCH isomers in the culture environment, suggesting th [ABSTRACT FROM AUTHOR]

Schizophrenia is a common disease characterized by thinking obstructions and accompanied by cognitive, emotional and behavioral disorders. Under the control of psychiatric symptoms, patients with schizophrenia may self-injure or impulsively wound others, resulting in public risk and increase in the burden of family and society. In recent years, many studies have shown that the violent behavior of patients with schizophrenia is related to genetic factors. This article reviews the research progress on the relationship between genetic polymorphism and violent behavior of patients with schizophrenia, analyzes the possible mechanism of the correlation between the two, puts forward the limitations of current research and the directions of future research, and provides scientific basis for risk assessment and prevention of violent behavior of patients with schizophrenia.

By using GC-ECD, the concentrations of organochlorine pesticides hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in the shellfish culture environment (sea water, sediments, and culture-shellfishes) in Xiamen sea area were analyzed, and the accumulation and degradation patterns of the HCH and DDT were preliminarily approached. In the sea area, there existed remarkable differences in the accumulation and degradation of HCH and DDT among different shellfish culture environments, being mostly associated with the habitation environment and physiological life habits of shellfish. The accumulated HCH isomers (Rx > 1) were mainly beta-HCH, delta-HCH, and gamma-HCH, whereas the degraded HCH isomers (Rx < 1) were mainly alpha-HCH. The ratio of alpha-HCH to gamma-HCH was less than or equal to 1.0, suggesting that the HCH was come from industrial HCH and lindane, most of the HCH had remained in the culture environment for a longer time, and a small amount of lindane was imported. The DDT in the sea water was aerobically degraded, its main degradation product was DDE, and the ratios of (DDD+DDE) to DDTs (p,p-DDE+p,p-DDD+o,p-DDT+p,p-DDT) was less than 0.5, whereas the DDT in sediments and shellfishes was anaerobically degraded, its main degradation product was DDD, and the ratios of (DDD+DDE) to DDTs was greater than 0.5, suggesting that there was a small amount of DDT newly imported in the sea water, and most DDT in sediments and shellfishes were already degraded and transformed into DDD and DDE. There were definite differences in the degradation rates of HCH isomers in the culture environment, suggesting the conformational change of HCH in its transformation processes in the shellfish culture ecosystem.