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To detect and differentiate two essential amino acids (L-Valine and L-Phenylalanine) in the human body, a novel asymmetrically folded dual-aperture metal ring terahertz metasurface sensor was designed. A solvent mixture of water and glycerol with a volume ratio of 2:8 was proposed to reduce the absorption of terahertz waves by reducing the water content. A sample chamber with a controlled liquid thickness of 15 μm was fabricated. And a terahertz time-domain spectroscopy (THz-TDS) system, which is capable of horizontally positioning the samples, was assembled. The results of the sensing test revealed that as the concentration of valine solution varied from 0 to 20 mmol/L, the sensing resonance peak shifted from 1.39 THz to 1.58 THz with a concentration sensitivity of 9.98 GHz/mmol∗L−1. The resonance peak shift phenomenon in phenylalanine solution was less apparent. It is assumed that the coupling enhancement between the absorption peak position of solutes in the solution and the sensing peak position amplified the terahertz localized electric field resonance, which resulted in the increase in frequency shift. Therefore, it could be shown that the sensor has capabilities in performing the marker sensing detection of L-Valine. [ABSTRACT FROM AUTHOR]

The Qing-1 layer of the Gulong Depression in the northern Songliao Basin is a liquid-rich shale oil reservoir that has the characteristics of nanopores, high maturity, high gas/oil ratio (GOR), etc. The production performance of wells in the Gulong shale oil reservoir shows the characteristics of "single gas production followed by oil-gas production". It is difficult to analyze the initial occurrence state and movability of fluid in the shale nanopores using conventional methods. In this study, a comprehensive method, including phase behavior analysis, physical experiments, and molecular simulation, was established to analyze the initial occurrence state and movability of fluid in the Gulong shale oil reservoir. The phase state of the fluid was calculated by the equation of state (EOS), considering nano-confinement effects, and the initial occurrence state was quantitatively evaluated by combining two-dimensional nuclear magnetic resonance (NMR) and molecular dynamics simulation. The movable fluid saturation was quantitatively determined by centrifugal experiments. The results show that the condensate gas state was in small pores, while the volatile oil state was in large pores. The occurrence states of oil were mainly adsorbed oil and free oil. The proportion of adsorbed oil in inorganic pores was about 24.4%, while the proportion of absorbed oil in organic pores was about 57.8%. Based on the cutoff value of T2 before and after the centrifuged laboratory experiments, the movable limit of oil was determined to be 4.5 nm, and the movable fluid saturation was about 11%. The research method proposed in this study has important guiding significance for the initial occurrence state and movability evaluation of similar liquid-rich shale reservoirs. [ABSTRACT FROM AUTHOR]

Background: At present, rice wine has the characteristics of fast fermentation, energy saving, and simple production due to the addition of commercial Saccharomyces cerevisiae. However, this kind of fermented rice wine has the disadvantages of single flavor and weak taste. To address this concern, the combination of Saccharomyces cerevisiae and non‐Saccharomyces yeast has been identified as an effective approach to enhance the quality of fermented rice wine. This research aims to further enhance the ethyl ester and higher alcohol components of rice wine by utilizing the co‐fermentation method of high‐yield ester Zygosaccharomyces rouxii and Saccharomyces cerevisiae, thereby increasing the aroma complexity of rice wine. Results: According to the fermentation performance and gas chromatography–mass spectrometry (GC–MS) analysis, it was found that S. cerevisiae GJM and Z. rouxii SC01 have a strong metabolic ability for glucose and sucrose. Furthermore, the crucial alcohols such as isobutanol, isoamyl alcohol, and phenylethyl alcohol increased by 85%, 29%, and 138%, respectively, when compared to single S. cerevisiae GJM. Additionally, the ethyl acetate and phenylethylene acetate were increased by 1.35 and 1.45 times, respectively, when compared to single S. cerevisiae GJM. These findings were comparable with the results of sensory evaluation and electronic nose analysis, where the fruit flavor score and the content of mellow substances were found to be higher. Conclusion: These findings suggest that the co‐fermentation of S. cerevisiae and high‐yield ester Z. rouxii has the potential to enhance the quality and diversity of aroma in liquid rice wine. [ABSTRACT FROM AUTHOR]