الفهرس 
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Abstract
Eichhornia crassipes, (water hyacinth), is an invasive, highly problematic, free-floating aquatic plant, with thick, broad, glossy and ovate leaves. Water hyacinth can rise above the water surface as 1 meter in height (3feet). E. crassipes (Pontederia crassipes) are vigorous growers plants that can double in size from one to two weeks [1]. The water hyacinth tolerance temperature is as described; the lowest growth temperature is 12°C, the optimum temperature of growth is 25-30°C, the highest temperature of growth is 33-35°C, and the pH tolerance is 5.0-7.5 [2]. E. Crassipes was reported to contain HCN, alkaloid, and triterpenoid, and may induce itching [3]. Water hyacinth has abundant nitrogen content, it can be utilized as a substrate for biogas production and accumulation of toxins, it has a high capacity for the uptake of heavy metals, including cadmium, chromium, cobalt, nickel, lead and mercury, that could make it suitable for the bio-cleaning of industrial wastewater and remove other toxins, such as cyanide [4-8]. This plants was a suitable host for many disease vectors, mosquitos and a type of parasitic snail flatworm that causes schistosomiasis [9]. Water hyacinth can also provide a food source for goldfish and keep water clean [10]. Chemical regulation of water hyacinths was performed by many herbicides as diquat and 2,4-D, glyphosate. The herbicides are sprayed on the water hyacinth leaves, this leads to direct changes to the physiology of the plant, it can cause death of water hyacinth through inhibition of the cell growth of new tissue and cellular apoptosis [11]. Physical method was performed by land-based machines as draglines, or boom or aquatic weed harvesters, or vegetation shredder or dredges [12]. Biological control was done by three species of weevil that feed on water hyacinth as, Neochetina bruchi, N. eichhorniae. These organisms regulate the growth of water hyacinth by limiting its vegetative propagation, its size and seed production. Cellulose is an organic polymer compound composed of a linear chain of β (1→4) linked D-glucose units [13, 14]. Cellulose is the structural component of the primary cell wall of green plants, algaes and the oomycetes. The cellulose content of wood is 40–50%, cotton fiber is 90%, and that of dried hemp is 57% [15, 16]. Cellulose has many properties as odorless, no taste, hydrophilic, chiral, insoluble in water and most organic solvents and biodegradable. It was shown to melt at 467°C [17]. It can be degraded into its glucose units by treatment with many concentrated mineral acids at elevated temperature [18]. Cellulose can be defined as straight chain polymer, and the multiple hydroxyl groups that found on glucose from one chain can form hydrogen bonds with oxygen atoms on the neighbor chain, so the chains held firmly together and forming high tensile strength microfibrils. Types of cellulose distinguished according to the location of hydrogen bonds between and within strands. Native cellulose is cellulose I, with Iα and Iβ structures. Cellulose produced from bacteria and algae is Iα while higher plants cellulose is Iβ. Cellulose in regenerated cellulose fibers is cellulose II. Conversion of cellulose I to II is irreversible process, cellulose I is metastable and II is stable. Chemical treatments may produce the cellulose III and cellulose IV structures. Cellulose is the major constituent of paper, paperboard, and card stock, electrical insulation paper, insulation transformers, cables, and other electrical equipment, in textiles. Microcrystalline cellulose and powdered cellulose are used as inactive fillers in drug tablets, emulsifiers, thickeners and stabilizers in processed foods, processed cheese to prevent caking inside the package, as additive in manufactured foods. Cellulose derivatives, as microcrystalline cellulose (MCC), used in reinforcement of drug tablets, plastics and resins industry. The thesis comprises of three chapters as follow: Chapter 1: This chapter reviewed a general introduction about polymer types, natural fiber properties and types, methods of fiber treatment, utility of Eichhornia crassipes, cellulose chemistry, pollution of water by dyes, dyes classification, adsorption technique, structure of CV, CR, application of cellulose in water treatment, drug vehicles and cancer therapies, methylene blue structure, therapeutic utility of MB, cellulose as a drug vehicle, engineering applications, VER chemistry and application, VER composites, epoxy chemistry, application and epoxy composite. Chapter 2: This chapter concerns with the experimental part. The chemicals and their resources were mentioned. Collection and purification of aquatic weed were described followed by five types of extraction method, which are Soxhlet extraction, mercerization, mercerization with bleaching, acid hydrolysis and solvent exchange techniques. The steps of preparation of VER prepolymer, VER/HEMA, VER ecocomposites, epoxy ecocomposites, MB, CV, CR solution, loading of CV, CR, MB onto cellulosic carriers were described. The techniques used for loading measurement and kinetic mathematical equations were discussed. The techniques used for release measurement and kinetics mathematical equations were mentioned. The techniques and measurements for characterization were mentioned. The techniques used to evaluate antibacterial and anticancer activity were explained. Chapter 3: This chapter deals with the results which are summarized in the following parts. The first part: devoted to extraction of cellulose from E. Crassipes by different extraction methods. The cellulose extracted by 5% NaOH has the optimum physical, thermal and morphological characteristics. C-5% NaOH was used for adsorption of CV, CR dyes from aqueous solution. The physicochemical features were monitored by x-ray diffraction (XRD), Fourier transform Infra-red spectroscopy (FTIR), Scanning electron microscope (SEM) & thermogravimetric analysis (TGA). Batch adsorption studies were carried including effect of contact time, pH, temperature, dye concentration and weight of adsorbent. Batch adsorption studies of CR and CV dyes on C-5% NaOH indicates that the rough surface of C-5% NaOH improved the adsorption due to enhancing the available contact and adhesion. The percentage of removal decreased by increasing temperature and dye concentration. Langmuir isotherm models fit better with experimental data of adsorption of CV onto C-5% NaOH, however, Freundlich isotherm fits better for adsorption of CR onto C-5% NaOH. The second part: include preparation of MB dye and loading of MB on different cellulosic carriers, then studying the antibacterial and anticancer activity. Physicochemical features were monitored by XRD, FTIR, SEM, TEM. MB-(C-H2SO4+H2O2) showed high MB loading efficiency (66%). The mechanism of release was studied by applying zero order, first order, Higuchi, Hixon Crowell and Korsemeyer peppas equations. The antibacterial activity was studied for MB, cellulosic carriers before and after loading against gram positive bacteria as (Bacillus Cereus, Streptococcus Pneumoniae, Staphylococcus Aureus) and gram negative bacteria as (Klebsiella Pneumoniae, Escherichia coli, Proteus Vulgaris). The in vitro cytotoxicity of MB-(C-H2SO4+H2O2) was conducted on MCF-7 (breast adenocarcinoma from human), normal human cell line (WI-38) using MTT assay. FTIR, proved the involvement of the OH group of cellulose in the adsorption process. from XRD, the dye adsorption doesn’t influence the crystallinity of cellulose and there are no MB diffraction peaks. In SEM, after MB loading on different cellulosic carrier the roughness increased, due to covering the surface with dye molecules. TEM images presented a network-like structure, there is separated individual nanofibril in some area and aggregates in some others due to the high specific area and strong H-bond established between the nanofibril. After MB loading, the TEM images showed ruminant of dye molecules. The antimicrobial study of C-5% NaOH, WHF extract 2 and C-H2SO4+H2O2, MB-(C-5% NaOH), MB-(WHF extract 2), MB-(C-H2SO4+H2O2) and M.B showed significant activity against all bacterial strains, the possible mechanism of antimicrobial action may have attributed to inhibition of cell division by inhibition DNA replication. However, MB and MB-(C-H2SO4+H2O2) has a moderate and weak cytotoxic effect on normal cells WI-38. Cytotoxic effect of MB-(C-H2SO4+H2O2) was increased after 48 h owing to the high amount of MB that released from the cellulosic carrier. The mechanism which controls MB release kinetic process was studied by various kinetics equations. The kinetic models utilized were Zero-order, First-order, Higuchi, Hixson-Crowell and Korsemeyer-Peppas, models. The MB release was found to follow first-order kinetics rather than other models in pH = 5.4, 6.7 and 7.4. from the Korsemeyer-Peppas equation in pH = 5.4, 6.7 and 7.4 medium, n value lower than 0.5 and the release mechanism follows the Fickian diffusion mechanism. The third part: introduces the synthesis of VER, epoxy/cellulose composite and studying physical, morphological and thermal properties. The prepared composite was monitored by XRD, FTIR, SEM, TGA and DSC. FTIR study was utilized to explain the formation of VER, epoxy SUMMARY 6 resins and its eco-composite. FTIR of cellulose, confirm the removal of lignin and hemicellulose after treatment. In FT-IR spectra, the disappearance of peak at 908 cm-1 confirms the curing of epoxide group. In vinyl ester spectrum peak at 1727 cm-1 is due to the carbonyl group of the ester. In XRD, there were no remaining peaks of hemicellulose or lignin, the crystalline structure is formed via hydrogen bonding interaction and Vander Waals forces between adjacent free hydroxyl group on the cellulose surface. The characteristic diffraction peaks of cellulose were disappeared in the composites, demonstrating that the weight fraction of cellulose was well encapsulated by epoxy. The characteristics peaks of cellulose disappeared in the composites, demonstrating that the crystalline structure of VER doesn’t affected by cellulose addition. The TGA curve of the cured epoxy showed only one thermal decomposition platform, indicating a one-step process. For cellulose-epoxy composites, thermal stability was improved after the addition of cellulose to neat epoxy however at higher cellulose content (40%), the thermal stability of composites decreased. SEM analysis was utilized for direct observation of the composite surface, and to examine the resin-fiber interface. SEM of neat epoxy, river patterns were observed on the fracture surface and the mirror-like fracture surface was very smooth and the structural deformation showed a brittle failure of a homogeneous material. Fracture morphology of the epoxy/cellulose composites, the surface of the composite is rough and more sea-island structure, this indicates that the epoxy matrix and cellulose additive experienced good interfacial adhesion and improving the performance of the composites. SEM of VER the fracture surface exhibited a homogeneous system with smooth and flat surface morphology with slight phase-separation feature (some river line-markings) suggesting that typical brittle fracture behavior of VER. CHAPTER 1 INTRODUCTION 7 Renewable agriculture resources are utilized as a crude material for varied products. Recently organic chemicals that derived from petroleum resources had been replaced by those derived from plant origin (Fig 1.1.) [19]