Poornima Nadun | Rajarata University of Sri Lanka (original) (raw)

Papers by Poornima Nadun

ASURS 2024, 2024

Electrocoagulation (EC) can be defined as the electrochemical involvement of waste water treatmen... more Electrocoagulation (EC) can be defined as the electrochemical involvement of waste water treatment and an eco-friendly approach. In the traditional approach, direct current was employed to produce coagulants, polymetallic hydroxide species, by electrodissolution of metal electrodes such as aluminium (Al) and iron (Fe). Compared to other waste water treatment processes, the EC is a cost-effective method. However, the traditional electrocoagulation process that was conducted with direct current (DC) associates with certain drawbacks such as deposition of non-conducting material on the anode and passivation limits. The application of alternating current (AC) has been found to be a highly effective method to overcome the drawbacks of DCEC, and minimizes the higher electrode dissolution and minimize nonconducting material deposition by alternating the polarity of electrodes. In this study, current density, applied potential, frequency of current, initial pH, initial conductivity of electrolyte, temperature, operational time, electrolyte composition, electrode material, and configuration were studied for efficient removal of Ca and Mg in water. It was found that, the final pH of treated water depends on the initial composition of the electrolyte in the wastewater. Under optimal conditions of 14.00 volts, 300 Hz AC, and 90 minutes, with Al-Al electrode system, a removal of 80% Ca 2+ and 70% of Mg 2+ were achieved. EC carried out for 1000 µS/cm Na2SO4 and 1000 µS/cm CaCl2 + Mg(NO3)2 solutions, the final pH value reached approximately to 10.04, with the Na2SO4 electrolyte and 8.34 with the CaCl2 + Mg(NO3)2 electrolyte. For other Al-Fe, and Fe-Fe electrode configurations, different efficiencies were investigated.

SCIENCE JOURNAL OF GAMPAHA, 2023

The pH of a system plays a significant role in chemical and biological reactions, with the pH of ... more The pH of a system plays a significant role in chemical and biological reactions, with the pH of a soil being a key determinant in plant growth and soil organisms. Soil pH is affected by various factors such as soil composition, atmospheric conditions, and organic matter. The buffering capacity of soil is primarily determined by CO32- and HCO3-ions. Soil is classified according to pH as acidic, neutral, and alkaline. A moderate pH is suitable for plant growth and soil organisms. Major nutrients such as phosphorus directly affect soil pH. Soil pH is also affected by atmospheric pollution, where an increase in SOX and NYOZ compositions causes a decrease in pH.

Science Journal of Gampaha, 2023

The cement industry plays a conspicuous role in world industries. It distributes throughout the w... more The cement industry plays a conspicuous role in world industries. It distributes throughout the world as a result of an abundance of raw materials. Cement as far as we might be concerned was first evolved by Joseph Aspdin, an ambitious nineteenth-century British stonemason, who warmed a blend of ground limestone and mud in his kitchen oven, then at that point, pummeled the invention into a fine powder. The outcome was the world's first hydraulic cement, one that solidifies when water is added.

Soil pollution in relation to soil functioning, fate, and effects of pollutants in soil environme... more Soil pollution in relation to soil functioning, fate, and effects of pollutants in soil environments Soil pollution refers to the presence of poisonous chemicals (pollutants or contaminants) in soil, in excessive sufficient concentrations to pose a threat to human fitness and or the ecosystem. According to the food and agriculture organization of the United Nations, "soil pollution, refers to the presence of a chemical or substance out of place and/or present at a higher than the normal concentration that has adverse effects on any targeted organisms". Soil is a mixture of a variety of substances that can be classified into main 4 components. They are inorganic, organic, water, and air. Inorganic components can be classified as inorganic sand, inorganic salt, and inorganic clay. The coarse-grained sediments in size from 0.05mm to 2.0mm are referred to as sand. Sand facilitates to drainage and aeration. The fine-grained sediment in the range from 0.002mm to 0.05mm is referred to as silt. Silt promotes moisture of soil, and it limits drainage. Other fine-grained sediments that are smaller than silt < 0.002mm are referred to as clay. Clay particles well promote the water retained in the soil. These particles provide nutrients to the plants. The organic component of soil, forms as a result of the degradation of organic matter. Humus is partially degraded organic matter. The organic matter in soil provides nutrients, moisture, and aeration for plant growth. Soil is composed with atmosphere, hydrosphere, geosphere, and biosphere. Therefore, soil can be referred to as an ecosystem. As a result of this interconnection, soil plays the main role. When soil is polluted, it will affect to the number of areas as a result of these interconnections. This soil pollution can be from domestic and industrial waste, agricultural pollution, urban activities, and continuous deforestation, heavy metal, organic phosphate. Soil shows the number of properties. These properties can be divided into two categories as physical and chemical properties. The physical properties are color, texture, porosity, density, aggregate stability, and temperature. Soil chemical properties depend on the concentration of specific chemicals. Depend on its content (e.g., phosphorus, nitrogen, carbon, calcium, magnesium, sodium, potassium, sulfur, and trace elements.) This content results in other chemical properties of soil such as pH, conductance, and salinity. These chemical and physical properties support to function of soil. There are five major functions that can observe, which are medium for plant growth, habitat for soil organisms, water supply and purification, engineering medium, and recycling nutrient and organic wastes. Plant growth on soil depends on mechanical support, nutrient supply, water supply, oxygen supply, light, and heat. Soil provides all necessary things for plant growth except light. Therefore, the soil is referred to as a natural medium of plant growth. Soil provides habitats for many organisms that can be microorganisms and macro-organisms. The macro-organisms which are worms, rodents, insects, etc. The microorganisms which can be observed in soil are fungi, bacteria, actinomycetes, algae, and protozoa. The decaying plant

Sri Lanka is a South Asian tropical county. It has more than 2500 history. Therefore, Sri Lanka h... more Sri Lanka is a South Asian tropical county. It has more than 2500 history. Therefore, Sri Lanka has a deep rooted culture. We can see the main four regions in Sri Lanka according to climate. Which are wet zone, Intermediate zone, dry zone, and arid zone. According to these climatic zones, there are subcultures. The foods, clothes, religion, beliefs, habits, medical therapies, agriculture patterns, dancing, music, and social behavior are the main parts of culture. Foods are playing the main role in culture because life entirely depends on foods. Good food habits move us towards a healthy life. Sri Lanka is a country which was good food habits. But within foreign invasion, these good food habits were lost. Now, most Sri Lankans tend to take instant foods. As a result of it, there are many health issues. Foods are playing the main role in a healthy society. Actually, all things on our mother's hand. In the topic region, rice is the main food source that take off our hunger. The curries support to make it palatable. According to biology, we can define foods are the way that we acquire nutrients and carbon into our body. But human overgo that definition. S.L Doshi mentioned in his book "Anthropology of food and Nutrient" as "food is a biochemical process and products which sustain life. But it is not merely the source of biochemical needs, it also has a cultural dimension which helps a person to determine his food and nutrition habits and choices". There are main considerations given to the choices of food. That are palatability, quantity satisfaction, nutritional value, digestibility, toxic properties, seasonal availability, storage life, preparation requirements, and presentation. Palatability means whether pleasant to taste either raw or processed, alone or as a condiment to other foods. The ability to overcome hunger and supply the energy requirement of the consumer, without using up internal reserves or leading to obesity, mean by quantity satisfaction. Nutritional value means, the number of nutrients in food. Protein, fats, carbohydrates, fibers, minerals, and vitamins are required to the well-functioning of the body. These amounts of nutrients in food mean by nutrient value. No single plant product supplies all these nutrients. Therefore, we should take a collection of foods. Digestibility is the ability of digestion. Digestion is the complex process of turning the food you eat into nutrients, which the body uses for energy, growth, and cell repair needed to survive. All things in foods are not digestible. The best example is cellulose. Cellulose is made up of beta-D-glucopyranose. There is no enzyme to digest the beta-D-glucopyranose. Therefore, cellulose is remained as undigested. That is the meaning of digestibility. Some foods are toxic to the body when they are raw or mixed with others. This toxicity is referred to as toxic properties. The best example is manioc and ginger. Manioc and ginger never eat together because they can be poison to the body when their chemicals mix. Some ingredients are used to prepare food when they are abundant in some seasons. As a result of abundance, they are much cheap. Therefore, people tend to consume them. This is due to the seasonal availability. Some foods have limited storage life. Therefore, we should eat them very soon as possible. Some foods should be prepared to eat by removing unpalatable and inedible parts. And some foods can eat without any preparation techniques. The Hal flour is produced from Hal fruits (Vateria copallifera) by removing bitter from water treatment. Only within the above requirements, peoples never tend to eat foods, when they haven't good appearance. The presentation of food is also much important to consume them. The serving of food in accordance to defined ethnic and cultural standards is believed to render the food more aesthetically pleasing and thereby more palatable.

Biogeochemical cycles, 2021

Carbon cycle leads to an effective path in biogeochemical cycle. The carbon cycle The carbon cycl... more Carbon cycle leads to an effective path in biogeochemical cycle. The carbon cycle The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere and atmosphere as a CO2.It is the main manner of carbon in atmosphere and also CO,CH4, also cam be seen in atmosphere from little amounts. The carbon dioxide is green house gas, it support heating. Plant utilise this CO4 to produce there own foods for photosynthesis. As a result of this photosynthesis carbon in atmosphere enters into plant bodies. Photosynthesis is the main path of carbon fixation. Plants are the primary the primary producers in the planet. Animals microbes are mostly depend on plant. Herbivores are primary consumers and they entirely depends in plants. They eat plant parts as a result of it carbon that fixed in plant bodies enter into animal body through the food chain and weds and that carbon exchange between animals. The plants and animals produce energy by breaking organic food while utilizing O2 and produce CO2 .That CO2 release to atmosphere as a respiration product. And also plant and animals die when they reach to end of long journey. The microbes are work on bread Bob and produce CH4,,CO2 and other secretion. The CO3 2 ,HCO3ions are produce that ion products deposit in soil as Canbon,MgCO3 and anymore. As aa result of anaerobic conditions and high pressure the carbon contain in dead bodies turn into coal and fossil oil. Humans utilize this carbon resources to produce energy. As a result of it the stored carbon release into atmosphere.

This is my first paper that I write in my self. there may be much more mistakes .plz ignore it.

This paper will provide information about relation between temperature and organisms

This paper will provide information with critical logic about relation between soil and organisms

Water Absorption , 2021

Hi this paper will improve your knowledge.

Soil Profile, 2021

This document about soil profile

Poornima Nadun, 2020

this document will help to improve your knowledge in soil Physics

Soil formation 2020, 2020

This will help to improve your knowledge in this area

Books by Poornima Nadun

Story of Soil Evolution Number Zero Edit by Poornima Nadun, 2021

this book was prepared by me from using internet articles. special thank for that article owners.... more this book was prepared by me from using internet articles. special thank for that article owners.
this article collection will improve your knowledge in Soil science.