Monday, May 4, 2020
Concept paper free essay sample
A Concept Paper is about the in-depth analysis regarding an intangible thought, theory, or idea. The goal of writing a concept paper is to explain a particular idea to the audience or readers objectively. Whenever an idea has to be explained, a concept paper is needed. If the audience has no knowledge about the topic, your job should inform them. If your audience has some knowledge, your job is to add new things or new idea about the topic. A concept paper is prepared as a prelude to a full paper. The full paper may be a thesis, a program, a project, or anything that will require a longer time to prepare. It is expected that the concept paper should consist only of 1 or 2 pages. Or if you want to clear up some matters, it can go up to 5 pages. The concept paper may also be used as an instructional tool that may have developed as a result of extensive research, committee input and/or as a result of the outcome of a current project. Reverse osmosis, electrochemical methods, chemical precipitation, ion exchange, flotation, and membrane processes are some of he techniques that were discovered (Park et al. , 2010). Unfortunately, these techniques have some limitations. They cannot completely remove the metals. They also require high energy and reagents and they generate waste products such as toxic sludge which ARQ Eire disposal. In addition, these methods are restricted when used for the decontamination of marine systems with heavy metals in a low concentration range (Viral and Volleys, 2000).As a result of these inadequacies and inefficiencies, researchers have sought alternative ways of removing toxic heavy metals from aquatic systems. It was in the 1 asss when the researchers, in the field of environmental biotechnology, discovered a new and efficient method for heavy metal removal- absorption. Absorption is defined as the capability of biological materials to accumulate heavy metals from aquatic systems through metabolically physiochemical pathways Of uptake (Ally et al. , 2003). The mechanism of absorption is complex.It mainly works through ion exchange, collation, adsorption by physical forces, and entrapment of metals in spaces of the structural polysaccharide network and in interlibrary and interlibrary capillaries (Ally et al. 2003). The major advantages of this technology over the conventional ones include not only its affordability and availability but also its high efficiency- the minimization of chemical and biological sludge, the removal of heavy metals at low concentrations, and the recovery of metal following adsorption (Volleys, 2007).In the process of absorption, a biological material is regarded as the absorbent. Absorbents, which contain metal-sequestering properties, can come from industrial wastes, organisms that are easily available in large amounts in nature, and organisms of quick growth (Viral and Volleys 2000). They can be classified into two, the living organisms and the non-living biological materials. Living organisms include bacteria such as the gram- negative, gram-positive and controversial; fungi such as molds, mushrooms and yeasts; and algae such as the seaweeds, micro-algae and macro-algae (Park et al. 2010). On the other hand, non-living biological materials include industrial wastes such as waste sludge and mill residues; agricultural wastes such as the fruit and vegetable derivatives; and natural residues such as saw dust, tree barks, and weeds (Park et al. , 2010).. Seaweeds offer advantages for sorption mainly because of their structure- the presence of carboxylic and sulfates in their polysaccharides (Ally et al. , 2003). In fact, some species of seaweed evaluated by different researchers have indicated impressive absorption of metals (Hand and Volley, 1 999; Volleys et al. , 1999; Volleys and Holon, 19995; Figural et al. , 2000). Drooled et al. (1996) studied the ability of three species of seaweed namely Caecilian maxima, Lessoning fallacies and Derailleur potatoes and found out that they can remove copper, nickel, zinc, lead and cadmium in aqueous solution. Grampus awed was also confirmed by Volleys et al. (1999) to remove cadmium and copper from aquatic systems. The research team stated that the alginate in the cell wall is the one responsible for the metal sorption of the seaweed. It has also been demonstrated by Viral and Volleys (2000) that fungi can be used as absorbents for heavy metals since they are composed of a wide range of chemical groups that can attract and sequester the metals in biomass. Their cell walls are composed of structural polysaccharides, proteins and lipids that offer metal-binding functional groups (Ally et al. , 2003). In the study of Stock et al. 2006), dry biomass of three fungi species namely Carious campsites, Amanita muscular and Tetrameter g Ibos were tested for their absorption capabilities and results revealed that these fungi can remove copper, aluminum and antimony from aqueous solutions. According to Paragon et al. (2007), the cell surface of bacteria carries a net negative charge due to the presence of carbonyl, amine, hydroxyl, phosphate and skillfully groups and because of this property bacteria can attract and adsorb significant quantities of positively charged heavy metals.And so, cetera can also be used as absorbent. In fact, according to the study conducted by Lung et al. (2001) entitled Absorption of heavy metals by bacteria isolated from activated sludge, both gram-positive (Bacillus) and gram-negative (Pseudonymous) bacteria have the capacity to remove copper, nickel and lead. Waste materials, such as agricultural wastes, natural wastes, and the by- products from large-scale industrial operations, were also given extensive attention.Dried activated waste sludge from a sewage treatment plant can remove cadmium, copper and zinc according to Hamming et al. (2003), olive ill residues can remove copper according to Poignantly et al. (2002), and bossily can remove zinc according to Drooled et al. (1996). Agricultural wastes such as the Nanas commons peel, Paprika specious pods and Sodium guava peel, as investigated by Off et al. (2011 can adsorb cadmium. Also, natural wastes such as bark from Eucalyptus globules Labial and Pinups radiate have been found out to accumulate copper and zinc (Ruffian and Mulligan, 201 1).Feasibility studies have established that absorptive processes using non-living biomass are more effective than the absorptive processes that use vying microorganisms. This is due to the fact that living microorganisms require nutrient supply and complicated fabricator systems (Park et al. , 2010). In addition to that, due to the toxicity of the pollutants being extracted and other unsuitable environmental factors such as the temperature and the acidity of the system being treated, maintenance of a healthy population of microorganisms becomes difficult (Park et al. 2010). For these reasons, some prefer the use of non-living biomass as absorbents. However, there are a lot of attributes of living microorganisms which remain unexploited and these attributes are all valuable of extra attention since they may be of great use for specific applications (Park et al. , 2010). In fact, A. Mali mentioned that when some non-living absorptive metal removal is not possible, growing metal resistant cells can be applied to water systems.These cells can ensure better removal due to a combination of precipitation, absorption, and continuous uptake of metals after physical adsorption (Mali, 2004). With the economic advantages and the wide knowledge accumulated about the absorption technology, some new absorbents are currently promoted for immemorial exploitation (Viral and Volleys, 2000). However, there are no limits to expanding our knowledge about the science of absorption. We still need to acquire deeper understanding and provide accurate explanations of the phenomenon in order to utilize this technology to its maximum efficiency.
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