In view of the large energy consumption of the regeneration process in the chemical absorption decarburization process, on the basis of the enrichment classification flow process, the nanoscale ceramic film is used as a new heat exchanger between the enriched liquid and the regeneration gas. The porous ceramic film is capable of coupling thermal-mass transfer to effectively recover part of the water vapor and the heat carried in the regeneration gas, so as to reduce the regenerative energy consumption of the system. The effects of parameters such as regeneration temperature, flow rate, molar fraction of water vapor, and MEA enrichment temperature, flow rate, and MEA concentration of shunt on the hydrothermal recovery effect of ceramic membranes of different pore sizes and lengths were studied by using the heat recovery flux and water recovery rate as the indicators. The results show that the hydrothermal recovery performance of the ceramic membrane increases with the increase of MEA enrichment flow, but decreases significantly with the increase of the enrichment temperature. At the same time, with the increase of regenerative gas velocity and the molar fraction of water vapor in the regenerative gas, the heat recovery flux will increase. The heat recovery performance of the 10 nm ceramic membrane is better than that of the 20 nm ceramic membrane.

In order to promote the application of noise map in high-speed railway noise management, the high-speed railway noise map drawing technology based on the combination of noise prediction model and geographic information system (GIS) is studied. Firstly, according to the distribution characteristics of noise sources and line structure characteristics of high-speed railway, the prediction model of multi equivalent sound sources and the calculation method of sound barrier insertion loss of high-speed railway are optimized; secondly, a three-dimensional geographic information model of a high-speed railway is built in GIS software, and the railway noise prediction technology based on the model is developed again; then, the noise of discrete nodes is calculated, and the continuous noise distribution map is drawn by spatial interpolation. The research results show that the comparison error between the noise map of a high-speed railway drawn by this technology and the measured results is less than 1 dB (A), which verifies the accuracy and practicality of the high-speed railway noise map, and can be used as a reference for the railway noise management department to formulate noise control countermeasures.

Objective: To study the growth, accumulation and soil nutrient content of each overseeded species under different interharvesting intensity treatments of Eucalyptus, and to explore the best re-cultivation method suitable for mixed overseeded species after Eucalyptus interharvesting. Methods: In Guangxi state-owned Qipo forest, Eucalyptus tailorii with different planting densities (DH32-29) were mixed with Castanopsis hystrix, Mytilaria laosensis and Michelia macclurei, and four different treatments (CK, LT, MT and HT) were established for re-cultivation of Eucalyptus near-mature forests with different logging intensities, and the differences in growth conditions and soil physicochemical properties of each species were analyzed. Results: (1) As the proportion of Eucalyptus allocation decreased, the growth of Eucalyptus diameter at breast height, tree height and individual wood volume could be promoted; the growth of the three parameters of HT and MT Eucalyptus were significantly different from LT and CK. (2) The average wood volume per plant of the set species in the CK and LT treatments was Mytilaria laosensis > Michelia macclurei > Castanopsis hystrix, while in the MT and HT treatments it was Mytilaria laosensis > Castanopsis hystrix > Michelia macclurei. (3) The differences in soil aeration, total saturated water holding capacity, capillary water holding capacity, and field water holding capacity in soil layers of different depth varied. In the same soil layer, soil aeration, total porosity and capillary porosity were HT > CK > LT > MT; saturated water holding capacity and capillary water holding capacity were HT > CK > LT > MT, while field water holding capacity was CK > HT > LT > MT. (4) Organic matter, pH, total nitrogen, total phosphorus, total potassium, fast-acting nitrogen, fast-acting phosphorus, and fast-acting potassium changed with varying soil depth in each treatment.

This paper assesses South Africa’s massive infrastructure drive to revive growth and increase employment. After years of stagnant growth, this is now facing a deep economic crisis, exacerbated by the COVID-19 pandemic. This drive also comes after years of weak infrastructure investment, widening the infrastructure deficit. The plan outlines a R1 trillion investment drive, primarily from the private sector through the Infrastructure Fund over the next 10 years (Government of South Africa, 2020). This paper argues that while infrastructure development in South Africa is much-needed, the emphasis on de-risking for private sector buy-in overshadows the key role the state must play in leading on structurally transforming the economy.

The wet saturated flue gas discharged by coal-fired utility boilers leads to a large amount of low-temperature waste heat loss. Inorganic ceramic membrane is acid-base resistant and has strong chemical stability. It is an ideal material for recovering low-temperature waste heat from flue gas. The experiment of waste heat recovery of flue gas was carried out with inorganic ceramic membrane as the core, and the characteristic parameters of low-temperature flue gas at the tail of the boiler were analyzed; taking 316 L stainless steel as the comparative object, the strengthening effect of inorganic ceramic film on improving heat recovery power and composite heat transfer coefficient was discussed. The results show that the waste heat recovery of flue gas is mainly the evaporation latent heat recovery of water, accounting for about 90%; circulating water is used as cooling medium, and the waste heat recovery capacity of flue gas is stronger; compared with circulating water, when air is used as the cooling medium, the effect of inorganic ceramic membrane flue gas waste heat recovery is more significant, and the enhancement coefficient is as high as 9; increasing the flue gas flow is helpful to improve the heat recovery power and composite heat transfer coefficient; at the same time, inorganic ceramic membrane can also recover condensate with high water quality. The results of this paper can provide a reference for the application of inorganic ceramic membrane in flue gas waste heat recovery.

Horticulture is a widespread activity in family farming in the Transamazonian region—Pará, with emphasis on production aimed at the family’s own consumption. The lettuce cultivar Vanda (Lactuca sativa L.) represents a significant part of this production, which prioritizes the use of internal labor. The main objective of this work was to evaluate the development of lettuce CV Vanda grown in beds using organic compost and chemical fertilization (NPK). The criteria considered to evaluate this performance were: Root system development, plant height and total fresh mass production. The best averages in relation to root development occurred in the plots cultivated with organic compost in the proportion of 5 kg/m², due to its characteristics as a fertilizer and soil conditioner. The cultivation with the use of NPK provided the best averages in relation to the production of total fresh mass and plant height, results that were mainly attributed to the extra supply of nitrogen in the covering fertilization, which consisted in the addition of 10 g urea per square meter via soil. Statistical analysis showed no statistically significant difference regarding plant height for both treatments. And in relation to root development, the difference was statistically significant.