Agricultural modernization has become an inevitable trend of global agricultural development. The traditional greenhouse monitoring system has limitations, which cannot detect and deal with the abnormal environment in the greenhouse in time. In response to the above problems, this paper designs a greenhouse environment monitoring system based on STM32. The hardware part of the system uses STM32 as the main control module. The LD3322 speech recognition sensor is used in the speech module. Temperature and humidity sensor detection module using DHT11 digital sensor; Soil moisture using waterproof DS18B20 digital sensor; The actuator is controlled by a relay module. In addition, the LORA module is used in the wireless communication module, so that users can remotely monitor the situation of the greenhouse environment. In the light acquisition part of the software, the Kalman filter algorithm is used to analyze and process the data, and the serial communication protocol is used to transmit the collected data to the host computer. Through experimental debugging, the system realizes the function of speech recognition control and environmental temperature and humidity detection. The experimental results show that the greenhouse environmental monitoring and control system has high stability and reliability, can effectively solve the problems existing in the traditional greenhouse monitoring, and has certain application prospects and promotion value.
Fate and transport of <i>Cryptosporidium parvum</i> oocysts in repacked soil columns: Influence of soil properties and surfactant
Christophe Darnault, Zhenyang Peng, Chan Yu, Biting Li, Astrid R. Jacobson, Philippe C. Baveye
IF 2.8
Vadose Zone Journal
Abstract A series of laboratory experiments was performed to investigate the transport and retention of viable C. parvum oocysts in soil columns homogeneously packed with loamy sand soils (Lewiston and Greenson series) and sandy loam soils (Sparta and Gilford series), and under hydrologic conditions involving the presence of an anionic surfactant—Aerosol 22 in artificial rainfall. To characterize the effect of surfactant on the mobility of C. parvum oocysts in the soils used in this study, these results were compared with previous laboratory‐scale column experiments of a previous study using soils contaminated with oocysts, under conditions identical to those described here except for the absence of the surfactant in the percolating water. Quantitative polymerase chain reaction was used for the detection and quantification of C. parvum oocysts in soil leachates to assess their breakthrough and in soil matrices to characterize their spatial distribution. Alterations in the rate and extent of transport of C. parvum oocysts were discerned per the physicochemical parameters analyzed—soil types, soil chemistry, and surfactant—and resulted in either the enhancement or hinderance of C. parvum oocysts adsorption to surfaces, and their movement in soils. In the case of loamy sand soils, the transport of C. parvum oocysts through the soil matrices increased with the application of surfactant for Sparta series and remained at a similar level for Gilford series. Regarding sandy loam soils, the movement of C. parvum oocysts through the soil matrices increased for Greenson series and decreased for Lewiston series with the application of surfactant.
Agricultural modernization has become an inevitable trend of global agricultural development. The traditional greenhouse monitoring system has limitations, which cannot detect and deal with the abnormal environment in the greenhouse in time. In response to the above problems, this paper designs a greenhouse environment monitoring system based on STM32. The hardware part of the system uses STM32 as the main control module. The LD3322 speech recognition sensor is used in the speech module. Temperature and humidity sensor detection module using DHT11 digital sensor; Soil moisture using waterproof DS18B20 digital sensor; The actuator is controlled by a relay module. In addition, the LORA module is used in the wireless communication module, so that users can remotely monitor the situation of the greenhouse environment. In the light acquisition part of the software, the Kalman filter algorithm is used to analyze and process the data, and the serial communication protocol is used to transmit the collected data to the host computer. Through experimental debugging, the system realizes the function of speech recognition control and environmental temperature and humidity detection. The experimental results show that the greenhouse environmental monitoring and control system has high stability and reliability, can effectively solve the problems existing in the traditional greenhouse monitoring, and has certain application prospects and promotion value.
Fate and transport of <i>Cryptosporidium parvum</i> oocysts in repacked soil columns: Influence of soil properties and surfactant
Christophe Darnault, Zhenyang Peng, Chan Yu, Biting Li, Astrid R. Jacobson, Philippe C. Baveye
IF 2.8
Vadose Zone Journal
Abstract A series of laboratory experiments was performed to investigate the transport and retention of viable C. parvum oocysts in soil columns homogeneously packed with loamy sand soils (Lewiston and Greenson series) and sandy loam soils (Sparta and Gilford series), and under hydrologic conditions involving the presence of an anionic surfactant—Aerosol 22 in artificial rainfall. To characterize the effect of surfactant on the mobility of C. parvum oocysts in the soils used in this study, these results were compared with previous laboratory‐scale column experiments of a previous study using soils contaminated with oocysts, under conditions identical to those described here except for the absence of the surfactant in the percolating water. Quantitative polymerase chain reaction was used for the detection and quantification of C. parvum oocysts in soil leachates to assess their breakthrough and in soil matrices to characterize their spatial distribution. Alterations in the rate and extent of transport of C. parvum oocysts were discerned per the physicochemical parameters analyzed—soil types, soil chemistry, and surfactant—and resulted in either the enhancement or hinderance of C. parvum oocysts adsorption to surfaces, and their movement in soils. In the case of loamy sand soils, the transport of C. parvum oocysts through the soil matrices increased with the application of surfactant for Sparta series and remained at a similar level for Gilford series. Regarding sandy loam soils, the movement of C. parvum oocysts through the soil matrices increased for Greenson series and decreased for Lewiston series with the application of surfactant.
Distribution characteristics, enrichment patterns and health risk assessment of dissolved trace elements in river water in the source region of the Yangtze River
Abstract The security of water environment in the source region of the Yangtze River (SRYR) is vital to the water environment security of the whole basin. The results showed that the rivers in the SRYR were weakly alkaline and the values of total solid solubility (TDS), electrical conductivity (EC), turbidity concentration and salinity were higher than the values in the middle and lower reaches of the Yangtze River. The results showed that the dissolved trace elements detected displayed obvious regional distribution characteristics, showing a high concentration trend in the Chumar River, low in the Dangqu, and middle in the Tong River. All water quality indexes in the SRYR met the surface water environmental quality standard of class II based on GB 3838-2002 except Hg, while the average concentration of As exceeded 10 μg/L. The main enrichment elements in the SRYR were Li, Se, As and Pb, and their concentrations were far higher than the average concentration of the world rivers. Moreover, the HI and HQingrstion of children caused by As in the SRYR were greater than 1. This study could provide basic data for water environment protection and water resource management in the SRYR.
Distinct Dispersion of As, Cd, Pb, and Zn in Farmland Soils near Abandoned Mine Tailings: Field Observation Results in South Korea
Sung-Wook Yun, Donghyeon Kang, Won-Hyun Ji, Mun-Ho Jung, Chan Yu
IF 2.6
Journal of Chemistry
We investigated the characteristics of metal(loid) transport and dispersion in agricultural soils near an abandoned metal mine. Topsoil samples were collected from 162 sampling sites in the study area, including 1 in the mine tailing dumps, to analyze the total concentrations of As, Pb, Cd, and Zn. Subsequently, the metal(loid) transport and dispersion characteristics were investigated using geographic information system (GIS) technology. The results of this study clearly demonstrated the variation in the dispersal of As, Cd, Pb, and Zn from the mine tailing dumps to nearby agricultural soils and the element-specific spatial variability in their respective transport and dispersion characteristics. These findings suggested that compared with the migration behavior of Cd, Pb, and Zn, that of As has a farther-reaching impact on agricultural soils owing to its geochemical cycling in the soil and groundwater environment. This impact differed significantly in magnitude from that of the other investigated metals. Therefore, special consideration must be given to the migration behavior of As.
With the rapid development of the steel industry, the accumulation of steel slag increases year by year, occupying a large amount of farm land and leading the problem of environmental pollution and safety hazards. The current comprehensive utilization rate of steel slag is still very low in China, far behind the developed countries. The low comprehensive utilization rate of steel slag is a stumbling block to the green and sustainable development of the Yangtze River Economic Belt. Improving the comprehensive utilization rate of steel slag is an imperative way to resolve these problems and to realize sustainable development for the steel enterprise. Steel slag presents porous structure and large surface area; in addition, it is easy to separate from water due to its high density. Therefore, the application of steel slag in industrial waste water treatment has received intensive attention in recent years. This paper systematically introduced the research progress of steel slag resource utilization as absorbent materials for waste water and proposed the important improved method and critical problems for steel slag as absorbent materials.
Strength and durability of rapid set PVA fiber reinforced LMC for pavement repair
Ki-Won Kim, Chan Yu, Jae-Woong Han, Chan-Gi Park
IF 3
Polymers and Polymer Composites
This study evaluated the strength properties, chloride ion permeability and abrasion resistance of styrene–butadiene latex-modified polyvinyl alcohol (PVA) fibre-reinforced rapid-set cement concrete (LMFRRSC) for application to emergency repair of concrete pavements. Experiments were conducted to measure the compressive strength, flexural strength, splitting tensile strength, bond strength, chloride ion penetration and abrasion resistance of LMFRRSC for variable PVA fibre content (0, 0.05 and 0.10%); test results showed that these test parameters increased with the volume fraction of PVA fibre, satisfying all traffic-opening criteria for emergency concrete pavement repair. The PVA fibre additive effectively minimized crack formation generated as a result of high hydration heat in the early material stages and inhibited fibre ball development. Thus, the addition of PVA fibre enhanced the performance of LMFRRSC for emergency repair of concrete pavements.
