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There is a wind interference effect between greenhouses in a group arrangement of solar greenhouse groups. To ensure the structural integrity of greenhouse groups situated in valleys, it becomes imperative to analyze both the wind pressure distribution patterns and the wind interference effects. This arises from the recognition that the wind load coefficients applicable to solar greenhouse groups nestled within valleys deviate from those observed in flat plains. The application of the contour modeling method facilitated a realistic reconstruction of the authentic topography within the study area. Subsequently, a wind field simulation was executed specifically for the constructed valley. The resultant wind field data for the studied valley area were then obtained. In the valley, nine solar greenhouses were systematically arranged in a three by three configuration. Special attention was directed towards assessing the surface wind pressures derived meticulously from the simulated wind field and wind direction angle of 0°. The findings elucidate the following: (a) The wind speed ratio exhibits a diminution on the leeward side of the mountain as compared to the windward side, with a notably reduced wind speed ratio observed in proximity to the mountain. (b) An amplification effect is discernible in the peripheral zone adjacent to the leading row of greenhouses, proximate to the incoming airflow. Particular emphasis is warranted regarding the reversal of wind direction observed in the secondary row of greenhouses positioned along the north wall and front roof, specifically at a wind angle of 0°, owing to the pronounced influence of interference effects. Hence, when undertaking the design and construction of a cluster of solar greenhouses within the valley terrain of Tibet, meticulous consideration must be directed towards both the meticulous calculation of wind loads within the periphery of the greenhouses and the judicious selection of the grouping's location. [ABSTRACT FROM AUTHOR]

Culture pH is very crucial to hydrogen production in the photo-fermentation process. Excessively low pH can directly affect cell growth and hydrogen production by changing bacterial physiological characteristics. Thus, screening acid-tolerant strains that can alleviate acid stress with enhanced hydrogen production is essential. In this work, an acid-tolerant mutant Rhodobacter capsulatus AT11 was isolated by transposon technology, and its photosynthetic characteristic under different initial pH values was investigated. The results indicated that the H2 yield of AT11 at initial pH of 5.5 was 4682.64 mL·L−1, which was 310.65% higher than that of wild strain JL1, and the mutant gene in AT11 was electron transfer flavoprotein (etf). Then an etf-deletion mutant JL1401 was constructed by deleting etf to verify the effect of etf on H2 production and investigate the acid-tolerance mechanism. Its H2 production at initial pH of 5.5 was significantly increased compared to its parental strain JL1. In addition, its photosynthetic characteristic with ammonium additives was studied. Under the condition of 1.8 mM ammonium, hydrogen production was still up to 2637.14 ± 41.46 mL·L−1, while hydrogen production of JL1 was inhibited. Cornstalk hydrolysate was used to evaluate the practical application of the constructed acid-tolerant mutant strains. The hydrogen yield reached 249.3 ± 16.8 mL-H2·g−1-cornstalk and 285.3 ± 19.1 mL-H2·g−1-cornstalk by R. capsulatus AT11 and JL1401, which were 2.9-fold and 3.3-fold compared to that of WT strain JL1, respectively. [ABSTRACT FROM AUTHOR]

Ferroelectric spontaneous polarization is a common physical phenomenon that stems from the displacement of positive and negative charges in opposite directions within ferroelectric materials. Herein, ferroelectric BaTiO3/Co3O4/C materials were prepared and ferroelectric spontaneous polarization was used to successfully drive the efficient transfer of intrinsic free charges. This led to the acceleration of the Co3+/Co2+ cycle and enhancement of peroxymonosulfate (PMS) activation efficiency. The catalytic activity of as-obtained BaTiO3/Co3O4/C initially increased and then quickly decreased with the increase in the concentration of the triblock polymer (P123), with the best catalytic activity achieved at a P123 concentration of 4 g L−1. The degradation rate constant of the BaTiO3/Co3O4/C + PMS system was 5.6 times and 68 times higher than those of the BaTiO3/Co3O4 + PMS system and Co3O4 + PMS system, respectively. This was ascribed to the synergy of ferroelectric spontaneous polarization and C-induced electron transfer. Complete degradation of methylene blue was achieved within 8 min in the BaTiO3/Co3O4/C + PMS system, and the main active species were holes (h+), SO4˙−, and 1O2. Moreover, spontaneous polarization played an important role in this catalytic process. This study provides a novel strategy to enhance the Co3+/Co2+ cycling process for promoting PMS activation. [ABSTRACT FROM AUTHOR]

The effects of hydrolysis methods (hydrothermal, acid, alkali, hydrothermal-enzyme, acid-enzyme, and alkali-enzyme) on hydrolysate characteristics and photo fermentative hydrogen production (PFHP) of corn straw (CS) and sorghum straw (SS) were investigated. The optimum production of reducing the sugar of straw in different solvent environments was studied by one-step hydrolysis and co-enzymatic hydrolysis pretreatment through a 3,5-dinitrosalicylic acid method. The hydrogen production process by photolytic fermentation of hydrolysates of Rhodobacter sphaeroides HY01 was further analyzed through a gas chromatograph, including the differences in accumulated PFHP yield, chemical oxygen consumption (COD), and volatile fatty acid (VFA) composition. The results showed that the highest reducing sugar yield was obtained by the acid method among one-step hydrolysis. In contrast, acid-enzyme hydrolysis can further increase the reducing sugar yield, which reached 0.42 g·g−1-straw of both straws. Both CS and SS had the highest hydrogen yield from acid-enzyme hydrolysate, 122.72 ± 3.34 mL·g−1-total solid of straw (TS) and 170.04 ± 4.12 mL·g−1-TS, respectively, compared with their acid hydrolysates with 40.46% and 10.53% higher hydrogen yields, respectively. The use of enzymatic hydrolysis showed a significantly higher hydrogen yield for CS compared to SS, indicating that acid hydrolysis was more suitable for SS and acid-enzyme hydrolysis was more suitable for CS. [ABSTRACT FROM AUTHOR]