Direction Of Water Flow Research Articles

Role of traveling microplastics as bacterial carriers based on spatial and temporal dynamics of bacterial communities

Microplastics (MPs) are considered as distinct substrates for bacterial colonization, they can carry bacterial communities to travel around environments. The bacterial communities on traveling MPs prefer to be gradually consistent with those on local MPs that were always in the same environment, and this process of change in the bacterial communities on traveling MPs was called ‘localization’. However, the dynamics of localization process and their influencing factors are still unclear. Therefore, we simulated the MPs migration process along the water flow direction in the estuary. We used quantitative analysis to study the dynamics of bacterial communities on the migrated MPs. We found the localization characteristics depended on the differences between the former and latter environments, as well as the preexisting bacteria. The localization degree was higher when the former and latter environments were similar. In most cases, compared with the first cultivation of pristine MPs, the time for localization was shorter. Moreover, although the entire bacterial communities tended to be localized, the preexisting bacteria on the migrated MPs had selective effects on subsequent bacterial colonization. Furthermore, the preexisting bacteria on MPs could set up the connections with the bacteria that existed at the latter site, and the stability of the entire bacterial communities on the migrated MPs increased with time. Overall, our findings indicated that the localization characteristics of bacterial communities on traveling MPs were related to the precultured time and environmental differences, which were helpful to understand the colonized bacteria transportation and MPs ecological effects.

Subsurface mapping of petroleum product (diesel) spillage in Apapa, Lagos, Nigeria from geophysical, lithological, and hydrogeological studies

A multi-disciplinary method has been applied for the subsurface mapping of a diesel (refined petroleum product) spillage in the Apapa area of Lagos, Nigeria. The methods include geological, geophysical, hydrogeological, and geoinformatics approaches. Apapa is located within the eastern sector of the Dahomey Basin, Nigeria. Twelve profiles were probed, adopting a 2D Wenner configuration. Three 3D resistivity images were produced from the 2D profiles using ZONDRES 3D and SURFER 16. Additionally, six boreholes were drilled for lithological information and the determination of groundwater flow directions of the area. The study area is characterized by loose, fine to coarse grained sand underlain by peat. The sands were observed to be partly contaminated by diesel (spilled diesel). The 3D resistivity images revealed that the area is composed of 3 geoelectric layers; an organic debris layer (<15 Ωm), overlain by a clean sandy layer (15–54 Ωm), as well as a contaminated sand layer (>55 Ωm). The results showed that higher resistivity values were obtained at shallow depths ≤3 m which depicts the diesel contaminated sand. The 3D model also showed that the magnitude of contamination decreases from the southern part (close to the source of contamination) towards the north of the area. These results are in tandem with the principal flow direction of water which is from south to north, confirming that the pollution source is from the southern part of the area. The combination of the resistivity, groundwater flow direction, and lithological information, therefore, unraveled the source, direction, and extent of contamination in the study area for a successful remediation plan.

Hydrodynamic and dissolved oxygen–biochemical oxygen demand transport characteristics at the river confluence in China's largest alluvial plain—A modeling study

AbstractThe Yellow River flows through multiple provinces in China, shaping the North China Plain, the largest alluvial plain in China. As the control node of basin ecological environment, the confluence of Weihe River and Yellow River is deemed as the gateway to North China Plain. In this study, a numerical simulation of the Weihe River–Yellow River confluence is conducted using a 2D hydrodynamic model and a coupled transport model for dissolved oxygen–biochemical oxygen demand. The results show that: (i) The typical flow field with multiple backflow areas is formed at the stagnant area where main stream and tributary converge and abrupt channel change area in different hydrological periods. The spur dike here mainly affects the velocity of the Weihe River outlet. (ii) There is an obvious concentration transition mixing zone downstream of the confluence, and the width of the mixing zone gradually linear increases with the direction of water flow. (iii) The self‐purification ability of the confluence is strongest in dry period, weaker in level period, and weakest in wet period. Water bodies have stronger self‐purification capacity on riverbanks than in the middle, and it is stronger in the upper reaches of Weihe River compared to Yellow River. Lower reaches also have a stronger self‐purification capacity than upper reaches. The study results can serve as a scientific reference for protecting the ecological environment of the Yellow River.

Groundwater Level Analysis of Sathyamangalam Region, Tamil Nadu, India Using GIS

The Morphometric and groundwater analysis (water level and flow direction) of Sathyamangalam, having total area of 2.24 lakhs hectares was carried out using geographical information system (GIS). The Watershed characteristics such as slope, size, shape and Morphological Analysis such as linear aspects namely Stream order, Bifurcation ratio, Stream length, Length ratio and Areal aspects in particular Drainage density are analysed using ArcGIS software. And also, groundwater level for four years (2008, 2011, 2014 and 2017) and groundwater flow directions using Piezometric well data were also analyzed. In Watershed characteristics, the size of the study area is 2.24 Lakh ha and designated as sub- catchment watershed. The shape is circular i.e. Fan shape. The total length of contour line is about 11055.86 km and the average slope was 24.68% for 50m interval contour. In Morphological analysis, totally 6487 streams were observed and the total length of stream was 3758.2 km. The study location has bifurcation ratio ranging from 1.56 to 3.62 and length ratio of stream was calculated as 1.678 km/km2. In Piezometric analysis, the major water level changes occur in Northwest of Sathyamangalam. Here, the depth of water from the earth surface decreases from 12.67 m in the year of 2008 to 3.95 m in the year of 2017.

In front of the retreating ice-sheet: Fauna complex of central-western Poland in MIS 3–2 (Krosinko site)

A new locality in Central Europe (Krosinko, Poland) yields a rich fossil material of great taxonomical variety. Its location in the Warsaw–Berlin ice-marginal valley, where it forms a 1-m horizon at a the depth of 6–8 m, is suited to a taphonomic analysis aimed at reconstructing the paleoevents and depositional history of the late Pleistocene (MIS 3–2).Our analysis revealed that the material accumulated as the result of high-energy fluvial transport. This transport disturbed the original bone associations, as indicated by the lack of articulation, low refitting, and bone surface modification. During water movement, the bones were polished, abraded, pitted, and fragmented. Prior to that, however, taphonomic signatures were left behind by predators, humans, and plant roots. This is the first time that unquestionable burning marks have been found on woolly rhino remains from Poland.The secondary context of the faunal assemblage was confirmed by neodymium isotope studies of the faunal fragments and sediment. Given the results of sedimentological analysis from previous studies, these sediments can be associated with a high-energy braided river. The remains were moved along with paleobotanical material and flints in a westerly direction; this is suggested by the direction of water flows in the valley and the river waters supplying it.The deposition occurred within a single geologic event around 26 ka BP, as indicated by the youngest radiocarbon date of the remains, or ca. 19 ka BP, considering the geochronological constraints for the local LGM ice margin position in central and eastern Poland ∼22–18 ka, and the specified accumulation time of the sediments in which they were found. Secondary mineralization of manganese and iron on the bones was the final taphonomical process that impacted the remains.The combined taphonomic, palaeozoological, isotopic and geological results show for the first time for a Polish paleontological site how data integration improves interpretation and highlights the advantages of a multiproxy approach.

Pollution Characteristics of Heavy Metals in Surface Sediments of the Shuimo River in Urumqi, China

Heavy metal pollution in the surface sediments of urban rivers has a significant influence on the safety of city residents. This study explores the features of heavy metal pollution in the surface sediments of the Shuimo River and provides a theoretical basis for decision makers regarding river management and restoration. This study uses principal component analysis and kriging interpolation to analyse the pH values and pollution characteristics of nine heavy metals (As, Pb, Zn, Cu, Ni, Fe, Mn, Cr, and V) in 23 surface sediments of the Shuimo River. The results showed that the pH value of the surface sediments along the direction of water flow had a quadratic curve trend. Kriging interpolation revealed consistency in the spatial distribution of heavy metals and Fe, and the peak value was from Qidaowan to Weihuliang. There were significant positive correlations (p &lt; 0.05) between Fe and Pb; Mn, Cr, V, Cu, and Zn; and Mn, Cr, and V. The principal component analysis showed that the main heavy metals in the surface sediments of the Shuimo River were Fe, Zn, Cu, and As. The total amount of heavy metals was in the order of Fe &gt; Mn &gt; Zn &gt; V &gt; Cr &gt; Ni &gt; Cu &gt; Pb &gt; As, ranging from 11.27~18,760.97 mg·kg−1. The cluster analysis classified the nine heavy metals into four categories: Zn and Cu in the first category; Ni in the second; As and Pb in the third; and V, Cr, Mn, and Fe in the fourth.

“Mn(II) Curtain” in the riparian sediment at the lower reaches of the Hanjiang River, China

Manganese (Mn) is an abundant valent-variable element whose transformation plays an essential role in pollutant fates. This study investigated the distributions of total Mn (T-Mn) and its existing forms, such as exchangeable Mn (EX-Mn), those bound to carbonate (Carb-Mn), iron (manganese) oxides (Ox-Mn), organic matter or sulfide (Om-Mn), and residual lattice combined state Mn (Res-Mn) in three two-dimension sediment profiles of the riparian zone at the lower reaches of Hanjiang River, China, with different water flow directions caused by the dam. The mechanism for the distribution of the Mn forms was discussed through correlation analysis with other sediment indices and modelling studies using the hydrogeochemical simulation software PHREEQC. Results showed that Res-Mn dominated the whole profiles, and the Carb-Mn and Ex-Mn were accumulated and formed an “Mn(II) curtain” at the interface of groundwater and river water, most likely derived from reducing Ox-Mn and Om-Mn at low Eh of this area. The correlation analysis results demonstrated that T-Mn positively correlated with Fe, Ca, Mg, and P in the sediments, inferring the deposition of the primary geological environment or coprecipitation in the riparian zone. Both EX-Mn and Carb-Mn were positively correlated with the average depth of the sampling site and the moisture content of sediments, indicating that the reductive environment below the water level was more favourable for the accumulation of EX-Mn and Carb-Mn. Ox-Mn tended to accumulate above the groundwater level, and Om-Mn were mainly enriched in the subsurface of farmland. The modelling results suggested that the formation of “Mn(II) curtain” was related to the release of CO2 pressure, high HCO3– concentration from the regional groundwater or the aerobic decomposition of TOC from river water, and the low Eh caused by the depth or exhaustion of the DO from river water. This study helps us understand the hydrogeochemical process and environmental fate of Mn and related pollutants in the riparian zone.

Optimization of Cooling Channel Structure of Bipolar Plate for Proton Exchange Membrane Fuel Cells Based on CFD Analysis

The working temperature affects the performance of PEMFC, so a reasonable and efficient cooling channel is necessary to control the working temperature in an efficient area. In this study, the channel structure of the bipolar plate for PEMFC is analyzed using the FLUENT simulation calculation method. The influence of cell size and cooling water flow direction on cell temperature distribution is analyzed, including an examination of the channel ridge width, depth, and aspect ratio of the bipolar plate. After comparing and analyzing three ridge width sizes (0.5 mm, 1.5 mm and 2 mm) in the paper, it was found that a ridge width of 2 mm had the best heat transfer performance. And it was found that a groove depth of 0.5 mm had the best heat transfer performance when comparing three groove depth dimensions (0.5 mm, 1 mm and 1.5 mm). The aspect ratio size parameters had almost no effect on the maximum and average temperatures of the electric stacks, while the relative flow direction of cooling water had a great influence on the temperature distribution of the bipolar plate.

APPORT DE LA GEOMATIQUE ALA DELIMITATION DES PERIMETRES DE PROTECTION AUTOUR DE LA PRISE DEAUPOUR LALIMENTATION EN EAU POTABLE SUR LA RIVIERE ME A KONGOFON (SUD EST DE LA COTE DIVOIRE)

The quality of the Me Rivers water is threatened by sources of pollution generated in the region without any measures being taken to protect this resource.So, to reduce the risk of pollution of this water resource, this study aims to delimit the protection perimeters around the water intake on the river.The methodological approach consisted firstly in assessing the vulnerability of the resource through the weighting and combination of five selected parameters, and then in determining the protection perimeters on the basis of the pre-established vulnerability map and data from previous studies.The pollution vulnerability map obtained reveals five classes of vulnerability around the water intake, with a dominance of the high class estimated at 29.44% of the watershed. Three protection perimeters have been defined. The immediate protection perimeter has a 200 m radius around the water intake and covers areas with a strong influence on the rivers vulnerability to pollution over a surface area of 1.97 km2.The close protection perimeter, covering a 1000 m radius, was delimited from the immediate protection perimeter. It covers an area of 43.7 km2 and takes into account the rivers low, medium and very high vulnerability classes, following the direction of water flow in the Me watershed.The remote protection perimeter covers a large part of the watershed, with an area of 1,480 Km2. It covers the rest of the catchments highly vulnerable areas and adjoins the close protection perimeter.The defined protection perimeters can serve as a guide for sustainable management and protection of river quality.

Simulation on TN and TP Distribution of Sediment in Liaohe Estuary National Wetland Park Using MIKE21-Coupling Model

A hydrodynamic-water quality model was established using MIKE21 to analyze the distribution of total nitrogen (TN) and total phosphorus (TP) in the wetland sediments of Liaohe Estuary National Wetland Park. The purpose of this model is to investigate the spatial and temporal variation patterns in wetland sediments and the distribution of pollutant contents. The research determines the applicability of this model in accurately predicting these patterns. The simulated contour map of the water quality concentration displays significant variation characteristics and reflects the actual concentration of pollutants in the wetland sediment of the Liaohe Estuary, proving the coupled model to be reasonable and accurate. The water quality simulation results indicate that water flowing through the wetland aids in purifying pollutants in the sediment, and the purification effect is more significant during the flood season. The MIKE21 model’s treatment reveals that the content of TN in wetland sediments decreases from southwest to northeast in the surface layer, following the flow direction of surface water. As the depth increases, the content of TN also decreases, with the bottom layer showing a decrease from southwest to northeast. The TP in wetland sediments receives surface water runoff and diffuses from upstream to downstream. The content of TP gradually decreases with increasing depth.

Evolution and health risk of indicator microorganisms in landscape water replenished by reclaimed water

As an important means to solve water shortage, reclaimed water has been widely used for landscape water supply. However, with the emergence of large-scale epidemic diseases such as SARS, avian influenza and COVID-19 in recent years, people are increasingly concerned about the public health safety of reclaimed water discharged into landscape water, especially the pathogenic microorganisms in it. In this study, the water quality and microorganisms of the Old Summer Palace, a landscape water body with reclaimed water as the only replenishment water source, were tracked through long-term dynamic monitoring. And the health risks of indicator microorganisms were analyzed using Quantitative Microbial Risk Assessment (QMRA). It was found that the concentration of indicator microorganisms Enterococcus (ENT), Escherichia coli (EC) and Fecal coliform (FC) generally showed an upward trend along the direction of water flow and increased by more than 0.6 log at the end of the flow. The concentrations of indicator microorganisms were higher in summer and autumn than those in spring. And there was a positive correlation between the concentration of indicator microorganisms and COD. Further research suggested that increased concentration of indicator microorganisms also led to increased health risks, which were more than 30% higher in other areas of the park than the water inlet area and required special attention. In addition, (water) surface operation exposure pathway had much higher health risks than other pathways and people in related occupations were advised to take precautions to reduce the risks.

Hydrodynamic Characteristic Analysis and NSGA-II Optimization of a Vacuum Fish Pump

The fish pump is an important piece of power equipment for aquaculture, especially for deep-sea engineering vessels and cage culture. Fish pump research focuses on reducing fish body damage, improving survival rates, and increasing fish lifting efficiency. The research object in this paper is a new type of vacuum fish pump, with the aim of improving the hydraulic performance of the vacuum fish pump and reducing the damage to the fish body. The dependent variables include the dynamic change process of the flow state and flow field under diachronic conditions, the fluid simulation analysis of the vacuum pump body and the flow channel structure, the inlet flow rate of the fish pump, the negative pressure of the pipeline, and the impact force of the water flow on the inner wall of the tank. The independent variables include the operating conditions of the pump body and the fish pump. The Latin hypercube sampling method is used to extract 167 sets of calculation models for the independent variables, and multi-objective optimization is performed based on the NSGA-II algorithm for the hydrodynamic performance of the fish pump. On the basis of ensuring the fish body damage rate, the structural parameters of the vacuum fish pump with the optimal hydrodynamic performance under 167 sets of parameter values were obtained. The optimized parameters were then entered into the solver again, and the results showed that, in the optimal structural parameters under certain conditions, the direction of the incident water flow in the vacuum fish pump tank is close to the upper end of the tank body, which will reduce the speed of the fish-water mixed flow when entering the tank, thereby reducing the collision damage to the fish body. Currently, the water flow velocity at the water inlet is about 2.5 m/s, and the negative pressure value distribution gradient between the tank body and the water inlet pipeline is quite consistent, which can achieve good fish suction and fish lifting effects.

APPORT DE LA GEOMATIQUE ALA DELIMITATION DES PERIMETRES DE PROTECTION AUTOUR DE LA PRISE DEAUPOUR LALIMENTATION EN EAU POTABLE SUR LA RIVIERE ME A KONGOFON (SUD-EST DE LA COTE DIVOIRE)

The quality of the Me Rivers water is threatened by sources of pollution generated in the region without any measures being taken to protect this resource.So, to reduce the risk of pollution of this water resource, this study aims to delimit the protection perimeters around the water intake on the river.The methodological approach consisted firstly in assessing the vulnerability of the resource through the weighting and combination of five selected parameters, and then in determining the protection perimeters on the basis of the pre-established vulnerability map and data from previous studies.The pollution vulnerability map obtained reveals five classes of vulnerability around the water intake, with a dominance of the high class estimated at 29.44% of the watershed. Three protection perimeters have been defined. The immediate protection perimeter has a 200 m radius around the water intake and covers areas with a strong influence on the rivers vulnerability to pollution over a surface area of 1.97 km2.The close protection perimeter, covering a 1000 m radius, was delimited from the immediate protection perimeter. It covers an area of 43.7 km2 and takes into account the rivers low, medium and very high vulnerability classes, following the direction of water flow in the Me watershed.The remote protection perimeter covers a large part of the watershed, with an area of 1,480 Km2. It covers the rest of the catchments highly vulnerable areas and adjoins the close protection perimeter.The defined protection perimeters can serve as a guide for sustainable management and protection of river quality.

Full-scale operation of an integrated aerated biofilter–denitrification shallow biofilter system for simultaneous nitrogen and phosphorus removal from low-carbon domestic sewage: Influencing parameters, microbial community and mechanism

At present the problem of not satisfying the increasingly strict emission standards in the biological treatment of domestic sewage characterized by high nitrogen and phosphorus stress has become prominent, especially under the insufficient carbon source. For the efficient treatment of low-carbon sewage, a full-scale integrated system was constructed and practically applied, which is based on a combination of an up-flow aerated biofilter and a denitrification shallow biofilter (UAB-DSB). The effects of operation parameters such as air/water ratio, hydraulic load, C/N ratio, and polyaluminum chloride (PAC) dosage on nitrogen and phosphorus removal were investigated. With the optimal parameters, the maximum removal efficiencies of chemical oxygen demand (COD), NH4+-N, total nitrogen (TN), and total phosphorus (TP) reached approximately 90%, 85%, 80%, and 92%, respectively, achieving an excellent quality effluent. Based on the water quality changes along the filter layer height, a dynamic equation for predicting NH4+-N removal was established, which can be applicable to different hydraulic loads. High-throughput sequencing analysis results indicated that the dominant bacteria genera were Longilinea, Nitrospira, and Terrimonas in UAB, while those in DSB were Longilinea, Ornatilinea, and Thauera. As proved by metagenomic analysis, the nxrA and nxrB genes encoded key enzymes in the nitrification, while narG, napA, nirS, norB, and nosZ genes were mainly responsible for the denitrification. By analyzing the spatial variations of the microbial communities and functions, the main mechanisms underlying the UAB-DSB system along the water flow direction were in turn carbon removal, ammoniation, synchronous nitrification and denitrification, aerobic denitrification, and heterotrophic denitrification.

Evaluation of Backwash Time Effect on Mesh Self-Washing Filter Parameters

Purpose: The study aims to determine the effect of the backwash time on the parameters of the mesh self-washing filter. Theoretical framework: The duration of the backwash process can significantly affect the operation parameters of the mesh self-washing filter Method: During the study, experiments were carried out using a laboratory stand on which a mesh self-cleaning filter was installed. In the experiments, the filter operation parameters were measured at different values of the backwash time. Mathematical modelling methods were also used to determine the filtration efficiency. Results and conclusion: The results of the study showed that the backwash time significantly impacts the operation of the mesh self-washing filter. The optimal backwash time is from 20 to 30 seconds, while the percentage of filter clogging due to removing impurities during backwash is reduced by 20-25% compared to a shorter or longer backwash time. Research implications: These filters work on the principle of direct filtration when water passes through a sieve to remove suspended solids. The filter material is periodically cleaned by backwashing, which involves changing the direction of water flow through a sieve to remove accumulated solid particles. Originality/value: Water purification by suspended solids with a size of more than 100 microns is carried out by an amount of more than 99.5%. The filter provides reproducible cleaning quality, and the cleaning efficiency does not decrease from cycle to cycle.

Room-Temperature Growth of Morphoplastic Scandium Nanowires through Coordination-Induced Self-Assembly for White-Light-Driven Photocatalytic Degradation of Rhodamine

Photoactive nanowires play an important role on the photoelectric-related applications; however, the in situ large-scale growth of photoactive nanowires on the arbitrary substrate still faces a great challenge. Herein, for the first time, we develop a facile coordination-induced self-assembly strategy for preparing the nanowires with high photoactivity through keeping a high concentration of Sc(NO3)3 and tartaric acid (TA) aqueous solution at room temperature. Surprisingly, the nanowires can grow directionally along the direction of water flow on any substrate due to the growth mechanism driven by water molecules, showing that the proposed nanowires are morphoplastic depending on the direction of liquid flow. The formation of nanowires has been proved to be attributed to the synergistic effect of water molecule-involved hydrogen bonding between hydroxyl groups of TA ligands as well as the multi-coordination of Sc3+ ions. Meanwhile, the prepared nanowires are highly photoactive, showing a strong photooxidation ability toward rhodamine 6G dyes, with a degradation efficiency of about 95.8% within 40 min. This finding introduces a coordination growth mechanism of nanowires, which not only provides a great possibility for large-scale and low-cost synthesis of photoactive nanowires with morphoplastic features but also shows a good application prospect in water cleaning by the photocatalysis technique.

Directional Bending Sensor and Multiparameter Sensor Based on D-Core Multimode Fiber

For the sensor with interference between fiber core mode and cladding mode, the directional bending sensor can be realized by processing asymmetric structure on the cladding or using eccentric fiber, but the temperature and strain crosstalk of the sensor with interference between fiber core mode and cladding mode is large. In this article, a kind of fiber intermode interference sensor with asymmetric structure is proposed, which can realize vector bending sensing and reduce temperature and strain crosstalk. The designed D-core multimode fiber has cladding and air on both sides of the fiber core. When 0° and 180° bending are applied to it, the interference spectrum moves in different directions, thus realizing the recognition of bending direction. For curvature detection, in the curvature range of 0–0.62 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}^{-{1}}$ </tex-math></inline-formula> , the sensitivity of 0° bending is 11.00 nm/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}^{-{1}}$ </tex-math></inline-formula> , and that of 180° bending is −11.40 nm/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}^{-{1}}$ </tex-math></inline-formula> . For liquid level detection, the sensing sensitivity is 234 pm/mm with the range of 0–4 cm, and the linearity is 0.993. In addition, the temperature sensitivity is as low as 10 pm/°C, and the strain sensitivity is as low as −1.28 pm/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \varepsilon $ </tex-math></inline-formula> . The proposed sensor realized the directional bending sensing and liquid level sensing of intermodal interference. Its low sensitivity to temperature and strain can be used to avoid the cross-sensitivity problems. In the field of water flow detection, the simultaneous detection of water level and water flow direction can be realized by the proposed sensor.

Energy Harvesting of Deionized Water Droplet Flow over an Epitaxial Graphene Film on a SiC Substrate.

This study investigates energy harvesting by a deionized (DI) water droplet flow on an epitaxial graphene film on a SiC substrate. We obtain an epitaxial single-crystal graphene film by annealing a 4H-SiC substrate. Energy harvesting of the solution droplet flow on the graphene surface has been investigated by using NaCl or HCl solutions. This study validates the voltage generated from the DI water flow on the epitaxial graphene film. The maximum generated voltage was as high as 100 mV, which was a quite large value compared with the previous reports. Furthermore, we measure the dependence of flow direction on electrode configuration. The generated voltages are independent of the electrode configuration, indicating that the DI water flow direction is not influenced by the voltage generation for the single-crystal epitaxial graphene film. Based on these results, the origin of the voltage generation on the epitaxial graphene film is not only an outcome of the fluctuation of the electrical-double layer, resulting in the breaking of the uniform balance of the surface charges, but also other factors such as the charges in the DI water or frictional electrification. In addition, the buffer layer has no effect on the epitaxial graphene film on the SiC substrate.

IOT Based Smart Agriculture for Precession Irrigation - A Model

Abstract: The rapid development of Internet of Things (IoT) technology across all industries, from the automotive to home automation, had an impact on the agriculture sector as well, commonly known as "Smart Agriculture," which moved the entire sector from statistical to quantitative methods. These innovative ideas modify agriculture's current practises, open up new prospects, and help this industry overcome a number of obstacles. This study shows a system that makes use of the possibilities of these IoT and wireless sensing devices as well as the difficulties encountered when fusing these technologies for mutual benefit. This essay demonstrates how to use a smart agricultural application that allows users to monitor and modify soil moisture, temperature, and humidity.The capacity to remotely direct water flow anywhere the user pleases without being present in person. This is accomplished by using a soil moisture sensor that can measure soil moisture, a DHT 11 for measuring temperature and humidity, an Arduino to link the entire system together, and the IOT cloud as the system's database. Our only goal is to create an automated solution for remote gardening that is user-friendly

Metagenomic profiles of planktonic bacteria and resistome along a salinity gradient in the Pearl River Estuary, South China

Estuarine ecosystems undergo pronounced and intricate changes due to the mixing of freshwater and saltwater. Additionally, urbanization and population growth in estuarine regions result in shifts in the planktonic bacterial community and the accumulation of antibiotic resistance genes (ARGs). The dynamic changes in bacterial communities, environmental factors, and carriage of ARGs from freshwater to seawater, as well as the complex interrelationships among these factors, have yet to be fully elucidated. Here, we conducted a comprehensive study based on metagenomic sequencing and full-length 16S rRNA sequencing, covering the entire Pearl River Estuary (PRE) in Guangdong, China. The abundance and distribution of the bacterial community, ARGs, mobile genetic elements (MGEs), and bacterial virulence factors (VFs) were analyzed on a site-by-site basis through sampling along the salinity gradient in PRE, from upstream to downstream. The structure of the planktonic bacterial community undergoes continuous changes in response to variations in estuarine salinity, with the phyla Proteobacteria and Cyanobacteria being dominant bacterial throughout the entire region. The diversity and abundance of ARGs and MGEs gradually decreased with the direction of water flow. A large number of ARGs were carried by potentially pathogenic bacteria, especially in Alpha-proteobacteria and Beta-proteobacteria. Multi-drug resistance genes have the highest abundance and subtypes in PRE. In addition, ARGs are more linked to some MGEs than to specific bacterial taxa and disseminate mainly by HGT and not by vertical transfer in the bacterial communities. Various environmental factors, such as salinity and nutrient concentrations, have a significantly impact on the community structure and distribution of bacteria. In conclusion, our results represent a valuable resource for further investigating the intricate interplay between environmental factors and anthropogenic disturbances on bacterial community dynamics. Moreover, they contribute to a better understanding of the relative impact of these factors on the dissemination of ARGs.