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【Objective】The use of artificial inoculation to ferment cigar tobacco leaves is an inevitable trend in the industrial production of cigar tobacco leaves, and the neutral aroma components are the important quality components of cigar tobacco leaves. The study aims to investigate the effect of Bacillus safensis GL2 on the neutral aroma components of cigar tobacco leaves.【Method】GL2 was screened from Cuban cigar Cohiba Robert and used to ferment cigar leaves. The neutral aroma components in tobacco leaves were determined by distillation extraction-gas chromatography-mass spectrometry, and multivariate statistical methods were used for analysis and statistics.【Result】The total aroma and the contents of most neutral aroma components in cigar tobacco leaves were significantly increased after GL2 fermentation (P < 0.05), and the increased aroma substances mainly included olefins, ketones and alcohols. A total of 13 differentially neutral aroma components were selected by VIP > 1 and P < 0.05, and 9 of them were significantly up-regulated and positively correlated with tobacco leaf aroma. There were 7 species with significant positive correlation (P < 0.05), which were the key differential aroma components of 2, 6, 6-trimethyl-2-cyclohexene-1, 4-dione, 2, 6, 6-trimethyl-1, 4-cyclohexanedione, geraniyl acetone, acanthyl acetone, neophydiene, solanone and phytoalcohol. In addition, 4 different aroma components were significantly decreased and negatively correlated with tobacco leaf aroma, among which 2, 4-di-tert-butyl-6-nitrophenol was significantly negatively correlated with cigar tobacco aroma (P < 0.05). 2, 6, 6-trimethyl-2-cyclohexene-1, 4-dione, geranyl acetone, solanone and phytol contributed significantly to the aroma of fermented cigar tobacco leaves, resulting in a stronger overall dry and floral fragrances. As a result, they enriched the aroma and improved the sensory quality of cigar tobacco leaves.【Conclusion】Inoculation of B. safensis during cigar tobacco fermentation is beneficial for improving the quality of cigar tobacco leaves, which provide theoretical support for improving the fermentation quality of cigar tobacco leaves with biotechnology.

Based on the results of drilling, tests and simulation experiments, the shales of the Cretaceous Qingshankou Formation in the Gulong Sag of the Songliao Basin are discussed with respect to hydrocarbon generation evolution, shale oil occurrence, and pore/fracture evolution mechanism. In conjunction with a substantial amount of oil testing and production data, the Gulong shale oil enrichment layers are evaluated and the production behaviors and decline law are analyzed. The results are drawn in four aspects. First, the Gulong shales are in the stage of extensive hydrocarbon expulsion when Ro is 1.0%–1.2%, with the peak hydrocarbon expulsion efficiency of 49.5% approximately. In the low–medium maturity stage, shale oil migrates from kerogen to rocks and organic pores/fractures. In the medium–high maturity stage, shale oil transforms from adsorbed state to free state. Second, the clay mineral intergranular pores/fractures, dissolution pores, and organic pores make up the majority of the pore structure. During the transformation, clay minerals undergo significant intergranular pore/fracture development between the minerals such as illite and illite/smectite mixed layer. A network of pores/fractures is formed by organic matter cracking. Third, free hydrocarbon content, effective porosity, total porosity, and brittle mineral content are the core indicators for the evaluation of shale oil enrichment layers. Class-I layers are defined as free hydrocarbon content equal or greater than 6.0 mg/g, effective porosity equal or greater than 3.5%, total porosity equal or greater than 8.0%, and brittle mineral content equal or greater than 50%. It is believed that the favourable oil layers are Q2–Q3 and Q8–Q9. Fourth, the horizontal wells in the core area of the light oil zone exhibit a high cumulative production in the first year, and present a hyperbolic production decline pattern, with the decline index of 0.85–0.95, the first-year decline rate of 14.5%–26.5%, and the single-well estimated ultimate recovery (EUR) greater than 2.0×104 t. In practical exploration and production, more efforts will be devoted to the clarification of hydrocarbon generation and expulsion mechanisms, accurate testing of porosity and hydrocarbon content/phase of shale under formation conditions, precise delineation of the boundary of enrichment area, relationship between mechanical properties and stimulated reservoir volume, and enhanced oil recovery, in order to improve the EUR and achieve a large-scale, efficient development of shale oil.

The geological characteristics and production practices of the major middle- and high-maturity shale oil exploration areas in China are analyzed. Combined with laboratory results, it is clear that three essential conditions, i.e. economic initial production, commercial cumulative oil production of single well, and large-scale recoverable reserves confirmed by the testing production, determine whether the continental shale oil can be put into large-scale commercial development. The quantity and quality of movable hydrocarbons are confirmed to be crucial to economic development of shale oil, and focuses in evaluation of shale oil enrichment area/interval. The evaluation indexes of movable hydrocarbon enrichment include: (1) the material basis for forming retained hydrocarbon, including TOC>2% (preferentially 3%–4%), and type I–II1 kerogens; (2) the mobility of retained hydrocarbon, which is closely related to the hydrocarbon composition and flow behaviors of light/heavy components, and can be evaluated from the perspectives of thermal maturity (Ro), gas-oil ratio (GOR), crude oil density, quality of hydrocarbon components, preservation conditions; and (3) the reservoir characteristics associated with the engineering reconstruction, including the main pore throat distribution zone, reservoir physical properties (including fractures), lamellation feature and diagenetic stage, etc. Accordingly, 13 evaluation indexes in three categories and their reference values are established. The evaluation indicates that the light shale oil zones in the Gulong Sag of Songliao Basin have the most favorable enrichment conditions of movable hydrocarbons, followed by light oil and black oil zones, containing 20.8×108 t light oil resources in reservoirs with Ro>1.2%, pressure coefficient greater than 1.4, effective porosity greater than 6%, crude oil density less than 0.82 g/cm3, and GOR>100 m3/m3. The shale oil in the Gulong Sag can be explored and developed separately by the categories (resource sweet spot, engineering sweet spot, and tight oil sweet spot) depending on shale oil flowability. The Gulong Sag is the most promising area to achieve large-scale breakthrough and production of continental shale oil in China.

Surface evapotranspiration is an important part of terrestrial hydrological cycle, and the analysis of spatio-temporal variation characteristics of evapotranspiration is the basis of in-depth understanding of hydrological processes in arid areas. Due to the lack of long-term observations of actual regional evapotranspiration in the Yinchuan Plain, it is difficult to obtain the spatio-temporal variation characteristics of long-term series evapotranspiration. Based on the MOD16A3 surface evapotranspiration data and the measured data of meteorological stations in the study area, this paper analyzes the variation characteristics and influencing factors of surface evapotranspiration in the Yinchuan Plain from the perspective of time and space by using the methods of Theil Sen median trend analysis, MK mutation test and CA-Markov model, and predicts the development trend of surface evapotranspiration in the next five years. The results show that from 2004 to 2019, the interannual variation trend of evapotranspiration in the Yinchuan Plain is increasing, and the MK mutation test results show that the year of 2010 is the mutation point of evapotranspiration time series data. There are obvious differences in spatial distribution pattern and change trend between the actual evapotranspiration (ET) and potential evapotranspiration (PET) in the Yinchuan Plain. Actual evapotranspiration shows an increasing trend in recent 16 years, and potential evapotranspiration shows a decreasing trend, which conforms to the theory of complementary evapotranspiration in arid areas. The future development trend of surface evapotranspiration in the Yinchuan Plain in 2024 is predicted with the CA-Markov model. The simulation results show that the evapotranspiration will still increase in the next five years. The spatio-temporal variation of evapotranspiration is affected by climate and human activities. Evapotranspiration is positively correlated with temperature, precipitation and sunshine hours, and is negatively correlated with relative humidity. Land use structure affects annual evapotranspiration. The results also show the rule: Evapotranspiration of paddy field > dry land > woodland > grassland > desert.

A method for simultaneous determination of 53 anti-infective drugs such as quinolones and sulfonamides in cosmetics was established by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/ MS). The samples were dispersed with saturated sodium chloride, extracted by ultrasound with 1% acetonitrile formate solution, and centrifuged. 0.1% Formic acid aqueous solution (containing 1 mmol/L ammonium acetate) and 0.1% formic acid methanol solution were chose as mobile phase, gradient elution was used, and electrospray ion source, positive ion multi-reaction monitoring mode (MRM) were used for determination with quantitative external standard method. The results show that the linear fitting of the 53 banned raw materials is good, with the correlation coefficient greater than 0.991 0, and the detection limit of 0.01-0.1 μg/g. The average recovery rates of sulfonamides and quinolones are 80.84% to 115.09% at low, medium, and high spiked mass concentrations. Among the 100 batches of samples screened, 1 batch is detected to contain sulfamethoxazole. The method has good sensitivity, selectivity and accuracy, and can be used for the determination of 53 anti-infective drugs in cosmetics. [ABSTRACT FROM AUTHOR]

Glioma is the most common primary tumor found in central nervous system of adult patients. The forkhead box protein M1 (FOXM1) is a member of the forkhead box transcription factor family, which can regulate Wnt/β-Catenin, Akt/FOXM1, p53 pathways and their own post-translational modification processes promote the malignant proliferation, migration, and invasion of glioma. These results of research provide new theoretical basis and therapeutic targets for the clinical treatment of glioma.