Metal chalcogenide hollow polar bipyramid prisms as efficient sulfur hosts for Na-S batteries

Funding Information: We appreciate the support from the National Natural Science Foundation of China (Nos. 21773188 and 21972111), Fundamental Research Funds for the Central Universities (XDJK2019AA002), Postgraduate tutor team-building project (XYDS201911). The work at UT was supported by the Welch Foundation (F-1841) and the Texas Advanced Computing Center.Peer reviewe

Quality Evaluation of Nine Varieties of Blueberry Based on Principal Component Analysis

To investigate the quality characteristics of different varieties of blueberry, the quality differences on appearance, physicochemical properties, and sugar and acid composition were analyzed. At the same time, correlation analysis was employed to analyze the correlation of different indexes and principal component analysis was employed to evaluate the quality characteristics of 9 varieties of blueberry. The results showed that different varieties of blueberry exhibited rich diversity in appearance, physicochemical properties, and sugar and acid composition. There was a high correlation between multiple indicators such as glucose and fructose (r=0.93), FRAP and DPPH (r=0.755). PCA results indicated that citric acid, pH, b*, total phenol, DPPH, flavonoid and juice yield were key indicators for evaluating the quality of blueberry, and the quality characteristics of 'Canlan', 'Laigexi' and 'Shuangfeng' were excellent fruit shape index (>0.73), good solid to acid ratio of 6.12~9.57 and suitable for fresh consumption. The quality characteristics of 'Baerdewen', 'Duke' and 'Weisan' included the high in sugar, acid and antioxidant capacity, suitable for juice and wine and other products development. The flavonoid contents of 'Weisan' and 'Duke' were 1.95 and 1.62 mg/g, and the total phenol contents were 1.34 and 1.38 mg/g, respectively. The quality characteristics of 'Weisan' and 'Duke' were high content of total phenol and flavonoid, suitable for functional product development. The results above will serve an important reference to screen blueberry varieties for different purposes

Effect of Different Tumbling Marination Methods and Time on the Water Status and Protein Properties of Prepared Pork Chops

The combined effect of tumbling marination methods (vacuum continuous tumbling marination, CT; vacuum intermittent tumbling marination, IT) and effective tumbling time (4, 6, 8, and 10 h) on the water status and protein properties of prepared pork chops was investigated. Results showed that regardless of tumbling time, CT method significantly decreased the muscle fiber diameter (MD) and significantly increased the total moisture content, product yield, salt soluble proteins (SSP) solubility, immobilized water component (p<0.05) compared with IT method. With the effective tumbling time increased from 4 h to 10 h, the fat content and the MD were significantly decreased (p<0.05), whereas the SSP solubility of prepared pork chops increased firstly and then decreased. Besides, an interactive effect between CT method and effective tumbling time was also observed for the chemical composition and proportion of immobilized water (p<0.05). These results demonstrated that CT method of 8 h was the most beneficial for improving the muscle structure and water distribution status, increasing the water-binding capacity and accelerating the marinade efficiency of pork chops; and thus, it should be chosen as the most optimal treatment method for the processing production of prepared pork chops

Paleosedimentary environmental reconstruction and mechanisms of the response to the Toarcian OAE in a lacustrine shale system

Abstract The Lower Jurassic Ziliujing Formation in China’s Sichuan Basin is a significant shale target for exploration; however, the strong heterogeneity of the properties of organic matter (OM) in shale makes it challenging to identify the target area for exploration, and the mechanism of OM enrichment is still unclear. Furthermore, the mechanisms of the response of the Da’anzhai member to the Toarcian Oceanic Anoxic Event (T-OAE) are controversial. Previous studies have focused on sedimentary facies analysis based on mineralogy and elemental abundances and have provided minimal information about organic geochemistry, which adds to the challenge of deeply understanding the influence of the T-OAE on the molecular geochemical characteristics of the Da’anzhai member. In this study, the Da’anzhai member of the Lower Jurassic Ziliujing Formation in the Langzhong area, Sichuan Basin, is studied via X-ray diffraction, total organic carbon, gas chromatography–mass spectrometry, organic carbon isotope, organic petrographical and pyrolysis analyses. To accurately identify the trend of the paleosedimentary environmental proxies, the Mann‒Kendall test is utilized to identify the trend of the data. Our results show that the Da’anzhai shale was deposited in a dysoxic transitional environment to an intermittent reducing environment with freshwater to brackish conditions. The response to the T-OAE can be identified in the middle and upper parts of the middle submember and the bottom of the upper submember of the Da’anzhai member. The T-OAE influenced the redox conditions, salinity, and OM origins during deposition in the middle of the Da’anzhai member, which resulted in the enrichment of OM. The abnormally high C30 diahopane/C30 hopane (C30D/C30H) ratio can be considered a potential proxy for locating the section of strata that responded to the T-OAE in the Da’anzhai member. In the study area, the mechanism of the response of the Da’anzhai shale to the T-OAE manifested as an improvement in hydrological cycling rather than a marine incursion. Our study provides new information that deepens the understanding of the mechanisms of the response of lacustrine shales to oceanic anoxic events from the perspective of molecular organic geochemistry

Fractionation of pyrrolic nitrogen compounds in petroleum during migration: derivation of migration-related geochemical parameters

Analysis of a range of crude oils and source rocks appears to indicate that primary and secondary oil migration has a strong impact on the distribution of pyrrolic nitrogen compounds in reservoired petroleum. The migration effects controlling the composition of pyrrolic nitrogen compounds recognized tentatively in this study include (a) the relative enrichments of alkyl carbazoles to alkylbenzocarbazoles, (b) nitrogen-shielded isomers to nitrogen-exposed isomers, and (c) higher homologues to the lower homologous species. A suite of molecular migration parameters based on chemical compositions of pyrrolic nitrogen compounds in crude oils have been proposed. If substantiated in more case history studies, these parameters are potentially useful in petroleum population mapping

Characterization of micro-nano pore networks in shale oil reservoirs of Paleogene Shahejie Formation in Dongying Sag of Bohai Bay Basin, East China

Abstract: For typical blocky, laminated and bedded mudrock samples from the Paleogene Shahejie Formation in the Dongying Sag of Bohai Bay Basin, this work systematically focuses on their structure characterization of multiple micro-nano pore networks. A use of mercury injection capillary pressure (MICP) documented the presence of multiple μm-nm pore networks, and obtained their respective porosity, permeability and tortuosity. Different sample sizes (500-841 μm GRI fractions, 1 cm-sized cubes, and 2.54 cm in diameter and 2-3 cm in height core plugs) and approaches (low-pressure N2 gas physisorption, GRI matrix permeability, MICP, helium pycnometry, and pulse decay permeameter) were used to measure pore size distribution, porosity and permeability. The average porosity and matrix permeability determined from MICP are (6.31±1.64)% and (27.4±31.1)×10-9 μm2, the pore throat diameter of pores is mainly around 5 nm, and the median pore throat diameter based on 50% of final cumulative volume is (8.20±3.01) nm in shale. The pore-throat ratios decrease with a decrease of pore size diameter. Moreover, the permeability of shale samples with lamination is nearly 20 times larger than matrix permeability. The geometrical tortuosity of the nano-scale 2.8−10.0 nm pore networks is 8.44 in these shales, which indicates a poor connectivity of matrix pore network and low flow capability. Overall, the variable and limited pore connectivity of shale samples will affect hydrocarbon preservation and recovery. Key words: Bohai Bay Basin, Dongying Sag, Paleogene, shale oil, pore structure, porosity, permeability, connectivity, geometrical tortuosit

Characterization of free and bound bitumen fractions in a thermal maturation shale sequence. Part 1: Acidic and neutral compounds by negative-ion ESI FT-ICR MS

To evaluate petroleum generation and expulsion processes, pyrolysis experiments that simulate increased overburden pressures were conducted on an immature organic-rich shale with type-II kerogen. Expelled oils and residual rocks with different maturities covering the oil window were recovered from the experiments. The residual rocks were then subjected to stepwise extraction in conjunction with stepwise dissolution of the carbonate and silicate minerals to obtain free and bound bitumen fractions. The compositions of acidic and neutral compounds in both expelled oils and bitumen fractions were investigated by negative-ion electrospray (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Neutral nitrogen compounds were found to only exist in expelled oil and free bitumen, while acidic compounds (typically contain carboxylic functional group(s)) were prevalent in bound bitumen. Oxygen-containing functional groups with high polarity in oxygen-containing compounds and oxygenated nitrogen/sulfur compounds are proposed to be the dominant bonding forces that facilitate the interaction between bitumen and mineral matrix or kerogen. Semiquantitative results of acidic compounds reveal that the distributions of acidic compounds in both free and bound bitumens vary throughout the oil window stage, especially for those in the bound phase after an intense oil expulsion from the shale at Easy%R-o > 0.9. During maturation, acidic compounds in free and bound bitumens gradually decreased in their abundances. However, oil expulsion from the shale brought about a significant redistribution of acidic compounds among expelled oil, free and bound bitumens. These results indicate that polar components in shales are closely related to thermal maturation of organic matter and oil expulsion from the shales in a petroleum system. (C) 2019 Elsevier Ltd. All rights reserved

Geological and geochemical data of 13634 source rock samples from 1286 exploration wells and 116489 porosity data from target layers in the six petroliferous basins of China

Geological and geochemical data of 13634 source rock samples from 1286 exploration wells in six representative petroliferous basins are examined to study their Active Source Rock Depth Limits (ASDL). Active source rocks and the discovered 21.6 billion tons of reserves in six representative basins in China and 52926 oil and gas reservoirs in the 1186 basins over the world are found to be distributed above the ASDL, illustrating the universality of such kind of depth limit