الفهرس 
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Abstract
Abstract
Plants require many nutrients and minerals to survive, which are either supplied from the soil or by fertilizer. Phosphorus is one of these minerals, which helps plants to form a set of buds and fruiting. The use of conventional phosphate fertilizers causes environmental pollution due to over-fertilization. Because of its large size, the plant cannot absorb all the amount of fertilizer and remains part of it in the soil has not been absorbed and less diffused. If too much phosphate fertilizer is used on the soil, excess phosphorus can easily find its way into water networks through storm and plumbing drains. Herbs and plant leaves grown in the soil with excess phosphorus will release phosphorus into the water, leading to outbreaks of algae, bacteria and water pollution, and resulting in poor soil and plant quality. For these explained reasons, many researchers found the importance of nano-hydroxyapatite as a potential fertilizer in improving the efficiency of phosphorus based on the hypothesis that nano-sized particles can potentially move in the soil and reach the plant roots through the mass flow of soil water to roots created by transpiration. So the usage of nano-phosphorus fertilizer can be a beneficial and safe way to improve soil fertility without causing any environmental pollution. Hydroxyapatite [HAp, Ca10 (PO4)6(OH)2] is one of the widely used bio-ceramics in different fields especially in medical and agricultural applications. Hydroxyapatite can be naturally prepared from biological wastes such as fish bones, bovine bones, coral reefs and egg shells, not only from the economical point of view but also as a friend of the environment.
Objective of the current work:
First: preparation of nano-hydroxyapatite from fish bone and eggshell:
1. Preparation of nano-hydroxyapatite from fish bone: by extracting it from the thorns using sodium hydroxide, acetone and concentrated hydrochloride solution to dispose of the organic matter found in the fish bone. The sample is then subjected to a high temperature 1100 °C to ensure that no residual organic matter only the inorganic material representing nano-hydroxyapatite remains.
2. Preparation of nano-hydroxyapatite from egg shell: As we know that the basic component of the eggshell calcium carbonate (CaCO3) when exposure to eggshell at a high temperature of 900 °C turns calcium carbonate into calcium oxide (CaO) and rising carbon dioxide (CO2). Calcium oxide is then reacted with ortho-phosphoric acid solution by the wet chemical precipitation method. The egg husk here represents a source of calcium, eventually producing the nano-hydroxyapatite.
Second: characterization of hydroxyapatite produced from both samples (from fish bone and egg shell) by biophysical techniques:
1. Infrared Spectroscopy (FTIR): The presence of functional groups of hydroxyapatite, OH-1 and PO4-3groups, were confirmed in both samples.
2. X-ray diffraction (XRD): Confirmed that the chemical structure of both samples is pure hydroxyapatite without any chemical impurities. The size of the crystallites could be calculated by using Scherrer equation which confirmed that both samples were in the size of the nanostructures 64.8 ± 0.36 nm in case of fish bone sample and 46.3 ± 0.32 nm in case of egg shell sample.
3. Transmission electron microscope (TEM): Used in the study of morphology and size determination and explained that the particles of both egg shell and fish bone samples in the size of nanostructures.
This study showed that not only fish bone but also egg shells can be used as bio-wastes for high quality nano-hydroxyapatite production with ideal properties for medical and agricultural applications.
Third: the use of nano-hydroxyapatite product in the field of agriculture as a phosphate fertilizer for the cultivation of some important economic plants such as wheat and soybean:
1. Application of nano-hydroxyapatite fertilizer for soybean cultivation: The current results showed significant differences in the growth rate of the use of hydroxyapatite produced from fish bone (F-HAp) and hydroxyapatite produced from eggshell (E-HAp) fertilizers compared with regular phosphorus fertilizer. The data obtained showed that the rate of growth of plants treated with nanoparticles was 1.88 times greater than the rate treated by traditional phosphate. Analysis of micronutrients revealed that the concentration of nitrogen (N), phosphorus (P) and potassium (K) in plants treated with F-HAp fertilizer was significantly greater than that of plants treated with regular phosphate with 1.21, 1.32 and 1.17, respectively.
2. Application of nano-hydroxyapatite fertilizer for growing wheat:
The weight of wheat spikes when using nano-hydroxyapatite from fish bone was 2.61 times higher than regular phosphorous fertilizer. Also when using nano-hydroxyapatite fertilizer, which is equivalent to 50% of the amount used in the case of conventional phosphorus fertilizer, the ratio of phosphorus was 1.21 and 1.06 times in the case of nano-hydroxyapatite from fish bone and eggshell, respectively.
from this study it was found that fish bones and eggshells can be used as biological waste for high quality HAp synthesis with properties for agricultural applications such as nano phosphorous fertilizer for soybeans and wheat. Data obtained indicate that both F-HAp and E-HAp were able to promote soybean and wheat productions compared to traditional phosphorus fertilizers, which needed further research in a larger area of the field.