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Recently, the exploration and development of the Chang 7 shale oil reserves and production have increased in the Ordos Basin. However, the characteristics of the Chang 7 reservoir vary greatly in different areas, which affect the exploration and development of shale oil. We used various analytical methods such as core observation, casting section, high-pressure mercury injection, nuclear magnetic resonance, X-ray diffraction (XRD), and logging interpretation to study characteristics of the reservoir in the Heshui area. The lithology of the Chang 7 member is mainly feldspathic quartz sandstone suggesting that the content of quartz is higher than that of feldspar, and it has relatively low carbonates. In addition, the kinds of feldspar are mainly plagioclase and potassium feldspar, and the concentration of clay minerals is 80%, mainly comprising illite and chlorite. The reservoir of the Chang 7 member is chiefly comprised of submicron pores, such as feldspar dissolved pores, intergranular pores, dissolved pores, microfractures, and intergranular pores. The porosity ranges from 6% to 12%, whereas permeability is less than 0.2 × 10−3 [Formula: see text]. The Chang 7 reservoir has a strong heterogeneity. Specifically, the heterogeneity of Chang 71 is weaker than that of Chang 72. There is a complex diagenesis such as compaction, dissolution, and cementation, and the compaction and cementation are relatively more and the dissolution is dominated by constructive diagenesis of feldspar dissolution. Sedimentary microfacies are one of the main factors controlling reservoir development. The physical properties of the reservoir in the branch channel are better than the edges of the branch channel and the lacustrine. The diagenesis affects the development and distribution of good reservoirs, and destructive diagenesis such as compaction and cementation reduces porosity and permeability. Conversely, dissolution increases the physical properties of the reservoir. Tectonics has no obvious effects on reservoir but plays a positive role in the migration and accumulation of hydrocarbon when microfractures developed.

The Chang 7 oil-bearing layers from the Ansai area of the Ordos Basin are abundant in oil and gas resources. These layers are chiefly comprised of shales interbedded with tight sandstone. In the regions where the exploration level is relatively low and the structures are gentle in the Ansai area, the distribution of fractures in shale reservoirs and tight sandstone reservoirs is significant for predicting sweet spots and determining the success rate of hydraulic fracturing. In this research, the results acquired from the scanning electron microscope (SEM), cores, thin sections, and image logging determined the developmental characteristics of fractures. Moreover, the Himalayan stress field was modeled using ANSYS, whereas the two-factor method is used to predict the distribution of tectonic fracture by combining stress field and fracture criterion. The results indicate a gradually decreasing trend of the maximum principal stress from east to west. The minimum principal stress in the western part is less than that in the eastern part. The differential stress that can indicate the degree of tectonic deformation ranges from 17 Mpa to 25 MPa. The fracture density ranges from 0 strip/m to 1.5 strip/m. In addition, the areas with more fractures are mainly located in the western and southeastern parts, where shale oil is relatively rich. Similarly, the comparison of different maps illustrates that the distribution of tectonic fracture is related to mechanical parameters and stress fields.

The addition of green tea as antioxidants to beer can improve the beer's flavor stability by protecting against staling during storage. To analyze the effect of different green teas on the flavor stability of beer, we developed an approach to rapidly evaluate their antioxidant activity. Ten types of craft beer were produced by adding different kinds of green tea during brewing, and their antioxidant activity and phenolic profiles were evaluated. The results showed remarkable variations in antioxidant activity and antioxidative compound contents, which were considerably higher in green tea beers than in non-tea beer (p 0.05). A comprehensive evaluation function was developed to evaluate the total antioxidant activity of beers using principal component analysis. The highest total antioxidant activity was observed in Taiping Houkui beer, with a comprehensive evaluation score of 2.53. Pearson correlation analysis suggested that (-)-epigallocatechin gallate, (-)-epicatechin gallate, and (-)-epigallocatechin were strongly correlated with the total antioxidant activity of green tea beers (p 0.01). The summation of their contents represented more than 60% of the total phenolic content of the teas, which can be used to predict the total antioxidant activity of green tea beers. PRACTICAL APPLICATION: Flavor stability is of prime concern for brewers, and flavor aging is increasingly becoming the limiting factor in beer shelf life. The application of green tea as antioxidants in beer can improve the flavor stability by protecting against beer staling during storage. The analytical method developed in this study will contribute to the rapid comparison of the effect of different green teas on the flavor stability of beer. Furthermore, the research findings demonstrate the potential benefits of green teas to beer flavor stability, which is of considerable importance in promoting the development and consumption of green teas.

A series of huge smoke plume events from the largest wildfire season recorded in California’s modern history has occurred in 2020. Here, a research algorithm was modified to retrieve the aerosol optical centroid height (AOCH) and aerosol optical depth (AOD) from Earth Polychromatic Imaging Camera (EPIC) measurements. The research focus is to gain insights of the algorithm’s feasibility in heavy smoke conditions to study the diurnal variation of AOCH; this is only made possible via EPIC due to its unique position at Lagrange-1 point and its equipment of O2 B-band at which the vegetated surface reflectance is low. Vicarious calibration is applied to the EPIC 443, 680 and 688 nm channels based on the Tropospheric Monitoring Instrument (TROPOMI) observation. This new calibration leads to a better agreement of AOCH values between EPIC retrievals and the counterparts derived from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aerosol extinction vertical profile. The hourly variation of AOCH up to 0.45 km on September 7 is shown to have important implications for estimating hourly change of surface PM2.5, although more quantitative studies are needed in the future.

Central Asia currently plays an important role on the global stage due to its geographical position and the region has been receiving increased research attention. We conducted a bibliometric analysis for the years 1900–2016 to evaluate differences in global research on Central Asia before and after the collapse of the Union of Soviet Socialist Republics (USSR), based on the Science Citation Index Expanded (SCIE) and Social Science Citation Index (SSCI) databases. This paper adopted a comparative analysis approach and summarized publication outputs, subject categories, country productivity, collaborations, title keywords and institution productivity on Central Asia before and after the collapse of the USSR. We analyzed the relationship between global research outputs on Central Asia and relevant impact factors, including the number of tourists, exports of fuel oil and gross domestic product (GDP). Comparing results before and after the collapse of the USSR, our bibliometric analysis revealed the following: (1) publications on Central Asia experienced a meteoric growth and publications in the SCIE played a dominant role after the collapse of the USSR; (2) Geology, Environmental Sciences & Ecology and Paleontology increased the most while Science & Technology—Other Topics, Geography and Anthropology decreased dramatically; (3) research countries became increasingly diversified and publications were produced by increasing numbers of international collaborations with a diversification of major collaborators; (4) the focus of title keywords differed before and after the collapse of the USSR; (5) institutions became more diversified and most of them focused on natural sciences; (6) there were high correlations between publications on Central Asia and the number of tourists, exports of fuel oil and GDP. These results reflect the close relationship between scholarly outputs on Central Asia and relevant factors, including the number of tourists, export of fuel oil and GDP. Increasing scholarly outputs on Central Asia therefore had a positive impact on global Central Asia research.

We present an algorithm for retrieving aerosol layer height (ALH) and aerosol optical depth (AOD) for smoke and dust over vegetated land and water surfaces from measurements of the Earth Polychromatic Imaging Camera (EPIC) onboard the Deep Space Climate Observatory (DSCOVR). Our algorithm uses EPIC atmospheric window bands to determine AOD and then takes advantage of oxygen A and B bands to derive ALH. We applied this algorithm on several dust and smoke events. Validation shows our results are of high accuracy.

Based on the evidence obtained from experiments on myocardial mechanics, some investigators1 have proposed taking the following indices as measures for the contractility of the intact heart, since these may be relatively less influenced by the factors before and after load on the heart: (1) the maximum rate of change in the left intraventricular pressure (expressed as dp/dt max.), (2) the ratio of dp/dt to the value of the instantaneous left intraventricular pressure (as (dp/dt)/p) and (3) the left intraventricular pressure-rate of pressure change loop (p-(dp/dt) loop, or simply ‘cardiac force loop’). These indices have been used widely in the investigation of hemonhagic, toxic as well as traumatic, shock2 and also in acute hypoxic tolerance of the heart3 to measure the condition of cardiac involvement. But in burn shock, most of the investigators evaluated the functional condition of the heart by determining the cardiac output and calculating the heart work4–6, and few of them approached this problem through direct measurement of the cardiac contractility on the basis of myocardial mechanics. In the work reported in this chapter, the cardiac contractility of dogs during the course of their Burn shock was estimated by measuring and calculating their first derivatives of the left intraventricular pressure, the velocity of shortening of the contractile elements of the myocardium (VCE) and the left intraventricular pressure — the rate of pressure change loop (p — (dp/dt) loop).