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Experiments and computational fluid dynamics (CFD) simulation were used to analyze the effects of the number and the diameter of oxygen supply ports, the flow rate and the mode of oxygen supply, and different modes of air flow (up-inlet and down-outlet on the same side, or on the different side) on the indoor oxygen enrichment characteristics and the effect of anoxic conditions in a closed buildings with or without air conditioning. Without air conditioning, the number and the diameter of oxygen supply ports, the flow rate and mode of oxygen supply, and formed oxygen-enriched regions are quite different. Using a double-45°-opposite oxygen supply ports with a diameter of 6 mm is advisable. Under the air conditioning condition, the number and the diameter of oxygen supply ports, the flow rate of oxygen supply, and the modes of air flow are different too. The formed oxygen-enriched area are all generally elliptical. It is advisable to use a single oxygen supply port with a diameter of 6 mm and an air flow mode of up-inlet and down-outlet on the different side. When the flow rate of the oxygen supply is the same, the oxygen-enriched area are formed by the wind speed of 0.85 m·s-1 is approximately 20% larger than that formed by the 1 m·s-1 wind speed. When the air supply wind speed is 0.85 m·s-1 and the oxygen supply flow rate is 1.5 m3·h-1, the oxygen-enriched area is approximately 0.96 m2, which is consistent with the area of the single-person activity. It is suitable as the basic oxygen-enriched supply for the single-person under air conditioning conditions where are lack of oxygen.

A set of experimental devices for the measurement of indoor oxygen supply in an enclosed architectural space was built. The devices were used to analyze the effects of the number and diameter of oxygen-feeding ports, oxygen flow rate, and oxygen-feeding mode on the indoor oxygen enrichment characteristics and efficiency of an architectural space. Results show that the distribution of the maximum axial oxygen concentration tends to decline with axial distance under different numbers and diameters of oxygen-feeding ports, oxygen flow rates, and oxygen-feeding modes. Axial oxygen concentration rapidly decreases when the axial distance to the oxygen-feeding port ranges from 0 m to 0.55. In general, the oxygen-enriched region that forms in a single oxygen-feeding port under different pipe diameters and oxygen flow rates presents a flat elliptical shape. The oxygen-enriched area expands under a constant oxygen-feeding pipe diameter and an increasing oxygen flow rate. The oxygen-enriched area that forms in double oxygen-feeding ports, wherein one is positioned vertically forward and the other port is positioned 45° opposite the forward-facing port, has a bifurcated shape with one pointed head and one rounded head. The oxygen-enriched area that forms in the vertical forward-facing port is larger than that in the 45° opposing port. Under back-to-back oxygen feeding, the oxygen-enriched area that forms in double oxygen-feeding ports with the pipe diameter of 6 mm generally exhibits a two-bladed fan shape, whereas that in double oxygen-feeding ports with the pipe diameter of 10 mm appears as two overlapping semicircles. Under the total oxygen delivery flow rate of 1 m3·h-1, the range of oxygen feeding in double oxygen-feeding ports with the pipe diameter of 6 mm and 45° angle is the largest and that in double oxygen-feeding ports with the pipe diameter of 10 mm and vertical forward position is the smallest. Under a constant total oxygen flow rate and oxygen-feeding mode, the oxygen-enriched area that forms in the single oxygen-feeding port in the vertical forward position is 20% larger than that in the double oxygen-feeding ports in the vertical forward position. Under the same number of oxygen-feeding port, oxygen flow rate, and oxygen-feeding mode, the oxygen-enriched area in the oxygen-feeding port with the pipe diameter of 6 mm is approximately 60% larger than that in the oxygen-feeding port with the pipe diameter of 10 mm.

Graphite carbon nitride (g‐C3N4) has garnered considerable attention due to its excellent photocatalytic properties for the degradation of organic matter in wastewater treatment. Herein, sulfur‐doped g‐C3N4 nanosheets (CN−S‐X) were successfully synthesized via physical steam activation using thiourea and urea as precursors. Comprehensive characterizations demonstrate that the enhanced photocatalysis is attributed to the ultrathin structure, highly active site, vacancy defects, and high specific surface area due to the synergy of S doping and steam activation. The as‐prepared CN−S‐25 photocatalyst exhibits a desirable degradation efficiency of 95.4 % for methylene blue dye with a high degradation rate of 2.65×10−2 min−1 under visible‐light irradiation, which are 2.1 and 5.52 times those for bulk g‐C3N4, respectively as well as good reusability and stability. This study provides a simple and promising strategy to regulate the nanostructure of g‐C3N4 for highly efficient photocatalytic degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

With the intensive development of animal husbandry, the demand for feed soybean meal increases. In order to promote the development of animal husbandry and ensure the supply and quality safety of feed in China, it is necessary to reduce the proportion of soybean meal and increase the development of protein feed resources and the supply of highquality feed. Cottonseed meal has high protein content, and the vitamin content is similar to that of soybean meal. Compared with soybean meal, cottonseed meal has a wide range of sources and is more affordable. However, cottonseed meal contains gossypol, which limits its application in animal production. Therefore, the dephenolization technology of cottonseed meal, the application of cottonseed meal instead of soybean meal in animal production and matters needing attention are summarized in the paper, which provides a reference for resource utilization of cottonseed meal, reducing livestock and poultry breeding cost and improving animal product quality. [ABSTRACT FROM AUTHOR]

The experiment was to study the quality and in vitro digestibility of total mixed fermentation diet treated with different proportions of reed grass and corn straw. The concentrate to roughage ratio of the diet was 35:65, and each group has consistent composition of concentrate (corn 13%, soybean meal 7%, flax meal 6%, bran 4%, wolfberry residue 5%). The coarse materials were reed grass and corn straw in different proportions. Reed grass and corn stalk were mixed in fresh weight ratios of 0:10 (group A), 2:8 (group B), 4:6 (group C), 6:4 (group D), 8:2 (group E), and 10:0 (group F), respectively, and combined with 35% concentrate feed. Cellulase and compound probiotics were used to ferment the total mixed diet prepared with different proportions of reed grass and corn straw combined with concentrate. Each group was set with three replicates and fermented for 30 days. The results showed that when the ratio of concentrate to roughage was 35:65, and the daily feed underwent enzymatic complex treatment with a roughage composition of reed grass to corn stalk at a ratio of 2:8, the overall sensory quality of the feed was better, with higher conventional nutritional value, maximum gas production, and the best combined effect. The study indicates that the ratio of reed grass to corn straw in roughage is 2:8, which is helpful to improve the utilization rate of reed grass and straw feed, reduce feed cost, improve economic benefit. [ABSTRACT FROM AUTHOR]