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The study of tectonic, provenance, and paleogeomorphologic systems is important for defining the basin evolution and it is also the basis for the accurate evaluation of oil and gas potential of a basin. The provenance and paleogeomorphology of the western Ordos Basin and the Hexi Corridor in the southwestern North China Craton(sw-NCC) have long been debated. In this study, detrital zircon geochronology, petrography and geochemistry methods are used to analyse the evolution of provenance and paleogeomorphology in the sw-NCC during the Middle–Late Triassic, and the provenance and paleogeomorphic relationships with tectonic events are discussed. The U–Pb detrital zircon geochronology of the Yaoshan samples in the western Ordos Basin are clear and consistent, and shows that there are three major age populations, 2700–2200 Ma, 2150–1650 Ma and 450–220 Ma. While the age spectrums of the samples from different formations in the Hexi Corridor are complex, showing significant differences. The whole results imply that the Hexi Corridor and the west margin of the Ordos Basin had a unified source during the Middle Triassic, which is the western NCC. However, in the Late Triassic, the sediment of the Hexi Corridor was mainly from the Qilian–Qaidam Terrane while the source of the western Ordos Basin remained unchanged. Besides the provenance analysis, the stratigraphic correlation, petrology and geochemistry analyses also support that the Hexi Corridor was temporarily connected with the Ordos Basin during the Middle Triassic but was separated from the Ordos Basin by a small-scale, underwater paleo-uplift during the Late Triassic. The evolution of the provenance and paleogeomorphology in the southwestern Ordos Basin was related to the closure of the shallow shelf of the Paleo-Tethys Ocean. [ABSTRACT FROM AUTHOR]

The Mesoproterozoic Jixian System (1.6–1.4 Ga) in the Luonan area, southern margin of the North China Craton (NCC), is characterized by complete development, continuous sedimentation and a low degree of structural deformation, resulting in well-preserved palaeontological and paleoenvironmental records. Carbon, oxygen and strontium isotopes of 382 dolostone samples from the Jixian System in Xiong'er Rift, southern margin of the NCC are analysed for the restoration of paleoenvironment and stratigraphic correlation. The results show that the δ13C values of these samples mainly concentrate between −1.8‰ and 2.0‰, and the values can be divided into three segments. The δ18O values are mainly between −6.5‰ and −3.5‰, with frequent fluctuations and weak regularity. The 87Sr/86Sr ratio ranges from 0.7051 to 0.7139, with an average value of 0.7085. Its fluctuations have certain regularity and are negatively correlated with the carbon isotopes, indicating that the sea-level changes during the Jixian period in the southern margin of the NCC. The carbon isotope curve of the samples from the study section is very similar to those of the Xiong'er Rift and the Yanliao Rift of the NCC. The −3.2‰ δ13C negative excursion in the middle and upper parts of the Xunjiansi Formation corresponds to the δ13C negative excursion from the top of the Wumishan Formation to the bottom of the Tieling Formation in the Yanliao Rift. Combined with previous research data, the Jixian System that deposited in the Xiong'er Rift and the Yanliao Rift can be approximately correlated with each other. In addition, the carbon isotope data obtained from this study is comparable to global carbon isotope values during the same period. The rise and oscillation of carbon and strontium isotope values during this period may be a response to the break-up of the Colombian supercontinent. [ABSTRACT FROM AUTHOR]

Zirconium dioxide is an important structural and functional material which is widely used in the field of gas sensor, fuel cell, ceramics, catalysis, and so on. This research takes urea as the precipitating agent, the anionic surfactant as template. Taking ZrOCl2as zirconium source, the research studies the factors that affect the experimental results such as the reaction temperature, reaction time, surfactant. Furthermore, the research detects and measures the obtained zirconia powders and discusses various conditions that affect the production of nano ZrO2. Taking chlorine oxidation zirconium and urea into reaction, the best conditions of each factor for single factor experiment are: reaction temperature is 80°C, reaction time is 20 h, surfactant is sodium dodecyl sulfate (SDS), and the calcination condition is 600°C (heating rate 5°C / min) for 4 h. [ABSTRACT FROM AUTHOR]

Non-small cell lung cancer (NSCLC) is related to the genetic and epigenetic factors. The goal of this study was to determine association of cigarette smoking and BPDE-DNA adducts with promoter methylations of several genes in NSCLC. Methylation of the promoters of p16, RARβ, DAPK, MGMT, and TIMP-3 genes of tumor tissues from 199 lung cancer patients was analyzed with methylation-specific PCR (MSP), and BPDE-DNA adduct level in lung cancer tissue was obtained by ELISA. Level of BPDE-DNA adduct increased significantly in males, aged people (over 60 years), and smokers; however, no significant difference was found while comparing the BPDE-DNA adduct levels among different tumor types, locations, and stages. Cigarette smoking was also associated with increased BPDE-DNA adducts level (OR = 2.43, p > .05) and increased methylation level in at least 1 gene (OR = 5.22, p < .01), both in dose-response manner. Similarly, cigarette smoking also significantly increase the risk of p16 or DAPK methylation (OR = 3.02, p < .05 for p16, and 3.66, p < .05 for DAPK). The highest risk of BPDE-DNA adducts was detected among individuals with cigarette smoking for more than 40 pack-years (OR = 4.21, p < .01). Furthermore, the present study did not show that BPDE-DNA adducts are significantly associated with abnormal TSGs methylations in NSCLC, including SCC and AdO, respectively. Conclusively, cigarette smoking is significantly associated with the increase of BPDE-DNA adduct level, promoter hypermethylation of p16 and DAPK genes, while BPDE-DNA adduct was not significantly related to abnormal promoter hypermethylation in TSGs, suggesting that BPDE-DNA adducts and TSGs methylations play independent roles in NSCLC. [ABSTRACT FROM AUTHOR]