scholarly journals Vermicompost for Mitigation of Surfactant Contamination in Surface Water

2020 ◽  
Vol 12 (3) ◽  
pp. 411-417
Author(s):  
M. A. Islam ◽  
S. Sarker ◽  
M. S. Nasrin ◽  
M. A. Hoque ◽  
M. S. Islam ◽  
...  

Surfactants are the most important pollutants of surface water which should be removed for the safety of aquatic life. The potentiality of vermicompost for the removal of surfactant contamination in surface water was studied by measuring surfactant concentration, pH and conductivity for nine days in six trials with different proportions of soil, vermicompost and phosphate keeping the surfactant concentration constant. The trials T1, T2, T3, T4 and T5 were considered as simulated ponds and T0 as control. The surfactant concentration, electrical conductivity and pH were found to change upon the application of vermicompost. The surfactant degradation rate of vermicompost amended systems was significantly higher than the control system.  Surfactant was almost completely depleted in vermicompost amended systems within the monitoring period. The presence of phosphate increases the surfactant removal efficacy of vermicompost. The pH values for vermicompost amended systems were almost constant near 7. The electrical conductivity of vermicompost amended systems was found to increase with time whereas that for the control systems was almost constant. Therefore, vermicompost can be considered as an excellent amendment as they have the ability to remove surfactant in surface water correcting the pH and increasing the availability of nutrients of the systems.

2013 ◽  
Vol 5 (2) ◽  
pp. 275-280 ◽  
Author(s):  
SMA Salam ◽  
MA Mollah ◽  
A Tasnuva ◽  
MR Zaman

Surface and ground water samples of Mohanpur Upazila of Rajshahi district have been analyzed in order to check its quality especially for drinking, fish culture, irrigation and industrial purposes. The water supplies were analyzed for pH, temperature, electrical conductivity, chloride, hardness, alkalinity, manganese (Mn), lead (Pb), cadmium (Cd) and arsenic (As). All water samples were tasteless at the time of collection. pH values for surface water were 7.72-8.61 and those of ground water were 6.87-710; Total hardness for surface water was 112-181 ppm and ground water was 224-400 ppm as CaCO3-; Electrical conductivity (EC) for surface water was 233-645 ?Scm-1 and that of ground water was 750-987?Scm-1. Total dissolved solids (TDS) for surface water were 161.1-451.9 ppm and ground water were 490.7-690.9 ppm. Chloride content for surface water was 81.79-131.78 ppm and ground water was 13.06-57.36 ppm; alkalinity for surface water was 398.21-539.73 ppm HCO3- and ground water was 373.81-495.80 ppm HCO3-; Nitrate for surface water and ground water was 2.10-5.20 ppm and 0.09-2.8 ppm respectively. Concentrations of Pb and As were within the permissible limit. Surface water was suitable for fish culture and agriculture purposes. However, a few water samples were found to be contaminated with Mn and Cd. It is concluded that the quality of ground water in the area is in general good for drinking, agriculture, industrial or domestic purposes.DOI: http://dx.doi.org/10.3329/jesnr.v5i2.14830 J. Environ. Sci. & Natural Resources, 5(2): 275-280 2012


2020 ◽  
Vol 5 (1) ◽  
pp. 101-106
Author(s):  
Doni Putra Utama

This research is a causality study with the title "Effect of Government Internal Control Systems and Employee Competence on the Performance of Government Agencies in Karimun Regency." The purpose of this study was to determine the effect of the implementation of the Government's Internal Control System on the performance of Karimun Regency government agencies and to determine the effect of employee competence on the performance of Karimun Regency government agencies. Data collection using a questionnaire where the questionnaire contained questions about the Government's Internal Control System, employee competencies and agency performance. Data were tested using multiple linear regression statistical tests. Based on the results of the study, it can be concluded that the governmental internal control system has a significant positive effect on Government Agency Performance with the results of statistical tests that show a sig value of 0.016 <0.05 (alpha 5%). Employee Competency has a significant positive effect on Government Performance with the results of statistical tests showing a sig value of 0,000.


Author(s):  
Jeremy A. Hartsock ◽  
Jessica Piercey ◽  
Melissa K. House ◽  
Dale H. Vitt

AbstractThe experimental Sandhill Wetland is the first permanent reclamation of a composite tailings deposit, and annual water quality monitoring is of specific interest for evaluating and predicting long-term reclamation performance. Here, we present water chemistry monitoring data obtained from Sandhill Wetland (years 2009–2019) and compare results to twelve natural reference wetlands and to environmental quality guidelines for Alberta surface waters. By comparing water quality at Sandhill Wetland and natural sites to established guidelines, we can begin to document the natural background water quality of wetlands in the region and examine if guideline exceedances are seen in natural undisturbed environments, or appear only at active reclamation sites. At Sandhill Wetland the dominant ions in near-surface water were bicarbonate, sulfate, chloride, sodium, calcium, and magnesium. Since the first growing season concentrations for these ions have increased annually, causing concurrent increases in electrical conductivity. In year 2019, water chemistry at Sandhill Wetland was most comparable to regional saline fens, systems that exhibit elevated electrical conductivity and high sodicity. Near-surface water at Sandhill Wetland exceeded water quality guidelines for three substances/properties (dissolved chloride, iron, and total alkalinity) in the most recent year of monitoring. The saline fen natural sites also exceeded water quality guidelines for the same chemical substances/properties, suggesting guideline exceedances are a norm for some natural wetland site types in the region. Of note, in each year of monitoring at Sandhill Wetland, dissolved organic compounds evaluated in sub- and near-surface water were below detection limits.


Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1291
Author(s):  
Balázs Németh

The paper proposes a novel learning-based coordination strategy for lateral control systems of automated vehicles. The motivation of the research is to improve the performance level of the coordinated system compared to the conventional model-based reconfigurable solutions. During vehicle maneuvers, the coordinated control system provides torque vectoring and front-wheel steering angle in order to guarantee the various lateral dynamical performances. The performance specifications are guaranteed on two levels, i.e., primary performances are guaranteed by Linear Parameter Varying (LPV) controllers, while secondary performances (e.g., economy and comfort) are maintained by a reinforcement-learning-based (RL) controller. The coordination of the control systems is carried out by a supervisor. The effectiveness of the proposed coordinated control system is illustrated through high velocity vehicle maneuvers.


Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 699
Author(s):  
Małgorzata Kucała ◽  
Michał Saładyga ◽  
Ariel Kaminski

Cyanotoxins are harmful to aquatic and water-related organisms. In this study, Lemna trisulca was tested as a phytoremediation agent for three common cyanotoxins produced by bloom-forming cyanobacteria. Cocultivation of L. trisulca with Dolichospermum flos-aquae in BG11 medium caused a release of the intracellular pool of anatoxin-a into the medium and the adsorption of 92% of the toxin by the plant—after 14 days, the total amount of toxin decreased 3.17 times. Cocultivation with Raphidopsis raciborskii caused a 2.77-time reduction in the concentration of cylindrospermopsin (CYN) in comparison to the control (62% of the total pool of CYN was associated with the plant). The greatest toxin limitation was noted for cocultivation with Microcystis aeruginosa. After two weeks, the microcystin-LR (MC-LR) concentration decreased more than 310 times. The macrophyte also influenced the growth and development of cyanobacteria cells. Overall, 14 days of cocultivation reduced the biomass of D. flos-aquae, M. aeruginosa, and R. raciborskii by 8, 12, and 3 times, and chlorophyll a concentration in comparison to the control decreased by 17.5, 4.3, and 32.6 times, respectively. Additionally, the macrophyte stabilized the electrical conductivity (EC) and pH values of the water and affected the even uptake of cations and anions from the medium. The obtained results indicate the biotechnological potential of L. trisulca for limiting the development of harmful cyanobacterial blooms and their toxicity.


1968 ◽  
Vol 1 (8) ◽  
pp. T.129-T.132 ◽  
Author(s):  
F. M. Toates

The reciprocal interaction between the accommodation and pupil control systems of the human eye is examined from a theoretical point of view. The system, which is responsible for maintaining pupil diameter at a value which is a compromise between conflicting requirements, is represented by a control model, and is considered in terms of the concept of a performance index.


1965 ◽  
Vol 180 (1) ◽  
pp. 246-259
Author(s):  
R. Ruggles

The author discusses some of the problems of failure-survival automatic flight control systems and suggests some basic ground rules as design criteria. The advantages and disadvantages of some of the main types of system are discussed: duplex, triplex, triple component, duplicate-monitored and quadruplex systems being covered. In particular, a quadruplex actuator is described which has been designed and developed mainly for automatic flight control system applications where a very high degrees of failure-survival capability is required. A detailed failure analysis of the various systems is carried out and the importance of the electrical and hydraulic supply system configurations and failure rates is brought out.


2021 ◽  
pp. 481-493
Author(s):  
Sarika Singh ◽  
Gargi Phadke

For any system to secure them industrial control system plays an important role in it. It helps to design the isolated procure system, specialized communication mechanisms is used to help for the setup. And with the help of this setup the flexibility, safety, threats, and vulnerabilities are the most important things to make. To secure them from risk assessment and other protection measurement need to specify with good instruments and security. The paper describes technical aspects on Denial of Service (Dos) attack. We also identify how smart grid communication networks works in security technical implementation guides of the different countries as a defense information systems agency. A brief chronicle of cyber storm on ICS; common challenges, some mitigation of those challenge, all levels of the multi-layered ICS architecture. This paper demonstrates railway control systems (RCS) compliance estimation of immovable control system design, operational scenarios that can be used for mitigation measures and security assessment.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Lin Meng ◽  
Yang Gao ◽  
Yangyang Liu ◽  
Shengfang Lu

Purpose As a short take-off and landing aircraft, FanWing has the capability of being driven under power a short distance from a parking space to the take-off area. The purpose of this paper is to design the take-off control system of FanWing and study the factors that influence the short take-off performance under control. Design/methodology/approach The force analysis of FanWing is studied in the take-off phase. Two take-off control methods are researched, and several factors that influence the short take-off performance are studied under control. Findings The elevator and fan wing control systems are designed. Although the vehicle load increases under the fan wing control, the fan wing control is not a recommended practice in the take-off phase for its sensitivity to the pitch angle command. The additional pitch-down moment has a significant influence on the control system and the short take-off performance that the barycenter variation of FanWing should be considered carefully. Practical implications The presented efforts provide a reference for the location of the center of gravity in designing FanWing. The traditional elevator control is more recommended than the fan wing control in the take-off phase. Originality/value This paper offers a valuable reference on the control system design of FanWing. It also proves that there is an additional pith-down moment that needs to be paid close attention to. Four factors that influence the short take-off performance are compared under control.


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