Chemistry

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    THE SYNTHESIS OF CHITOSAN DERIVATIVES AS A VERSATILE TOOL IN SUSTAINABLE AGRICULTURE
    (An - Najah National University, 2023-08-13) Renad Jalal Yahya Hamed
    Agro-fertilizers and pesticide chemicals are identified as primary agricultural and environmental pollutants. Chitosan polymer has attracted interest in agriculture and plant sciences applications; therefore, in this current research, considerable scientific contributions are ongoing to improve the formulation and functionalization of chitosan polymer. This research focuses on the utilization of chitosan in the synthesis of innovative nano bio-fertilizer capsules, aiming to deliver active agro nutrients, namely Nitrogen, Phosphorous, and Potassium ions (NPK), along with beneficial plant growth-promoting rhizobacteria (PGPRs) microorganisms. These entrapped components are coated using innovative cross-linking of chitosan and alginate with humic acid through ionic gelation and polyelectrolyte complexation technique. The morphological and structural characteristics of the formulated nano capsules are investigated using DLS, FT-IR, SEM, and TGA. The entrapped materials' encapsulation capability, water retention behavior, and release kinetics are also determined. The findings provide insights into implementing nano bio-fertilizers to deliver agro-nutrients, efficiently contributing to agricultural productivity and sustainability. On the other hand, the functionalization of chitosan with photocatalyst materials has emerged as a promising approach to developing bio pesticides. This research focuses on the functionalization of chitosan with three different photocatalyst materials: ZnO, carbon nano dots (CNDs), and a hybrid of (CNDs/ZnO), and their potential role as active antimicrobial agents against a broad spectrum of bacterial and fungal strains under dark and sunlight conditions. Functionalized chitosan photocatalyst materials' resulting morphological, structural, and optical properties were examined using FT-IR, AFM, XRD, RAMAN, and UV-Vis instruments. The findings provide insight into the ability to utilize these synthesized as bio-pesticides for agriculture purposes. Finally, the potential of functionalizing chitosan with amino acids as PGPRs and plant bio-stimulant products was also determined. A PGPR precursor named 1- amino cyclopropane-1- carboxylic acid (ACC) was synthesized and functionalized with chitosan. Also, different amino acids (L- Valine, L- Tryptophan, and L- Lysine) functionalized chitosan were synthesized using new approaches. The structural characteristics were also determined using FT-IR and NMR instruments. The plant agronomic and physiological parameters associated with these materials were examined. The findings provide insight into using these bio-stimulant products in agricultural applications.
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    VARIATION IN THE CHEMICAL COMPOSITION AND BIOACTIVE COMPONENTS OF MYRTUS COMMUNIS ESSENTIAL OILS FROM TWO PALESTINIAN REGIONS
    (An-Najah National University, 2023-02-05) Sumayyah Salim Mohammad Jaber
    One of the reasons why interest in medicinal plants is growing daily is the idea that some plants have the ability to treat a variety of illnesses without having any negative side effects. Myrtus has long been used in many conventional treatments in our region. In this study, the chemical profiles of the Myrtus essential oils (EO) that were gathered in Jericho and Jenin will be investigated, along with their antioxidant, anti-amylase, antimicrobial, and anticancer effects. Myrtus essential oils (EO) were created via hydro distillation extraction, and the chemical constituents of the EO were characterized qualitatively and quantitatively using GC-MS. Forty one chemicals were found in Jericho EO, with cis-4-Thujanol (27.37%), 1, 8-Cineole (24.32%), Myrtenol (12.97%), Myrtenal (12.46%), and trans-4-Thujanol acetate (9.48%) being the main contributors. There were 37 different chemicals in Jenin EO, with 1,8-cineole (31.55%), linalool (21.65%), Trans-4-thujanol acetate(11.26%), α-pinene(10.22%), Myrtenal(6.78%) and -terpineol(4.35%) being the most prevalent. The antioxidant activity of the EOs was assessed by blocking DPPH free radicals. Jericho and Jenin ethyl acetate extracts outperformed the positive control Trolox, which exhibited an IC50 of 10.25±1.02 g/mL, and demonstrated dose-dependent free radical scavenging capabilities with IC50 values of 8.55±2.31 and 3.60±0.35 g/mL, respectively. The most effective α-amylase inhibitory agents were Myrtus EO and extract from Jenin, with IC50 values of 950.48±2.54 and 795.43±1.88µg/mL, respectively, whereas EO and extract from Jericho had no effect. Jenin EO has higher antioxidant activity comparison to the EO from Jericho is presumably brought on by larger amounts of oxygenated monoterpenes, such as 1, 8-cineole and -pinene. The antitumor activity was tested using the MTS assay. Four cancer cell lines—the human cervical (HeLa), breast (MCF-7), mouse embryo fibroblasts (3T3), and normal hepatic (LX-2) cell line were employed as normal cell lines to test the anti-proliferative activity. Jenin EO has IC50 values between 215.25±1.07 and 597.01±3.11 g/mL, while Jericho EO has values between 644.47±2.89 and 914.54±3.05 g/ml. The antibacterial activity was examined using the microdillution technique. Gram-positive bacteria are more sensitive to both EOs than Gram-negative bacteria. The two EOs have less antifungal efficacy against C. albicans than any other extract under study. Keywords: Myrtus, Essential oil, Chemical composition, Bioactive components, Palestinian.
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    CELLULOSE BASED FOAM WITH IONIC FUNCTIONALITY: SYNTHESIS AND APPLICATION IN WASTEWATER PURIFICATION FROM TOXIC METALS
    (جامعة النجاح الوطنية, 2022-08-28) AbuAlrob, Haneen
    Abstract Background: The excessive applications of chemicals increased the load of contaminants in water. Organic, heavy metals ion, and inorganic contaminants pose a serious risk to creatures' life. heavy metal ions are one of the most harmful common contaminants. Scientists devoted their effort to finding an efficient, economic, commercially available, and environmentally friendly way to remove contaminants from water. Objectives: In this study, we benefit from Polyurethane foam (PUF) characteristics. PUF is easy to prepare and use in water purification. Elastic porous structure, controllable pore structure, adjustable shape, simple preparation process, high stability, and high adsorption/desorption rate. These properties make it very suitable for use as an adsorbent material for toxic metal ions. The lack of metal-binding groups in PUF limited its use in wastewater purification. PUF modified with an ionic functional group that is covalently attached to it will be synthesized and used as a metal adsorbent. Methodology: PUF preparation was carried out by polymerizing the diisocyanate compound with oxidized cellulose. The first step involved reacting cellulose with sodium periodate to produce dialdehyde cellulose. Produced dialdehyde cellulose was reacted with para-aminobenzoic acid to form a Schiff base. Schiff base was reduced by sodium borohydride to form cellulose amino benzoic acid. At the last step, a diisocyanate compound was added to form a foam with a 3D structure with carboxyl functionality. The presence of the carboxylate and amino benzoic acid groups in addition to the other PUF properties mentioned above makes the target foam novel for wastewater purification. The prepared polymers were characterized by using TGA, and FT-IR. The produced foam was used in extracting metal ions form wastewater. Optimum adsorption conditions for wastewater purification process using the prepared cellulose PUF polymers was detected. The adsorption conditions that lead to the highest efficacy were determined by running the extraction at various parameters such as: pH, contact time, temperature ℃, dosage, and initial metal ion concentration. Results: The effect of each parameter was evaluated by varying the parameter values while keeping others constant. The targeted parameters that lead to the highest efficacy were determined to be pH 7.0 and 9.0, contact time 30 and 25 min, temperature 15 and 20, dosage 250 mg, and initial metal ion concentration 15.0 and 20.0 ppm for PPUF and HMPUF respectively. An atomic absorption spectroscopy instrument was used to determine the concentration of lead after applying the polymer under certain conditions. After detecting the ideal parameters, the prepared polymers were applied to a real-life sample of wastewater. Under the optimum conditions, the efficiency of the polymers in lead removal was tested. Inductively Coupled Plasma Mass Spectrometer ICP-MS was used to determine the concentration of contaminants in the real-life sample (sewage water) after and before applying the polymer. the Langmuir model was fitted to the equilibrium adsorption data. Van't Hoff plot was used to determine ΔH°(KJ/mol), ΔS° (J/mol.K), and ΔG°( KJ/mol) values they were -7.693, and -31.44, and 9.53, -28.725, -107.2 and 32.44 for PPUF & HMPUF- NCC respectively. The results indicate that the adsorption process is spontaneous at room temperature. Kinetic study showed that the process obeys pseudo second-order the R2 value for the two polymers are very close to1. Conclusion: After detecting the optimum conditions polymers were applied to a real sample and the two polymers show excellent efficiency in the removal of heavy metals. Keywords: heavy metals, water pollution, cellulose, polyurethane foam, adsorption.
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    Synthesize and Characterization of Cellulose Derivataized with an Aromatic Amine and Application in Waste Water Purification
    (An-Najah National University, 2019-07-14) Abu Leil, Bahia
    A cellulose derivative with several coordination sites for metal ions composed of cellulose powder extracted from olive industry waste and 1,2-pheneylnediamine was synthesized and evaluated as an adsorbent for metal ions from sewage. The adsorption efficiency of the cellulose amine polymer toward Fe(III) and Cd (II) was investigated as a function of adsorbent dose, concentration temperature, pH, and time .The adsorption parameters that gives the highest adsorption efficiency were determined. In addition, the cellulose amine polymer showed an excellent efficiency toward approximately twenty metal ions present in the sewage sample. The highest adsorption efficiency was at pH of about 8.3, room temperature and with 2mg/ml of polymer dose. The cellulose amine polymer has various coordination sites amine, hydroxyl, and aromatic groups. The diversity and frequency of the coordination was the reason for the high efficiency of the cellulose amine polymer toward the metal ions. The thermodynamic analysis results (The Gibbs energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were calculated) supported the spontaneous adsorption efficiency of the polymer at room temperature. The kinetic study revealed that the metal ion adsorption by cellulose amine polymer was pseudo-second-order and followed the Langmuir isotherm model.
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    Cellulose Functionalized with Amine Bidentate Ligand: Synthesis and Use as A Polymeric Support for Palladium Catalysts
    (An Najah National University, 2021-02-09) Nazem Ghaleb Ali, Oraib
    Two novel polymeric palladium supported catalysts were prepared and evaluated in the oxidation of alkene and ketone. The obtained results showed that, the catalysts could be used in a lab scale or commercial scale to produce α-hydroxy ketones form ketones and ketones form terminal alkenes. The polymeric material was prepared by condensation reaction of an oxidized cellulose (cellulose di-aldehyde) and 2-(2-pyridyl)ethylamine to produce cell-imine-pyridyl. Oxidized cellulose was prepared by oxidation of cellulose using sodium periodate. The polymer was characterized by FT-IR spectroscopy. The polymers then reacted with a solution of Li2PdCl4 in acetonitrile to prepare the target polymeric palladium supported catalyst (cell-pyridyl-Pd(II)). A second polymeric palladium supported (cell-picolyl-Pd(II)) catalyst was prepared in the same manner except that 2-picolylamine was used in the place of 2-(2-pyridyl)ethylamine. Hydroxylation of ketone catalyzed with cell-pyridyl-Pd(II) and cell-picolyl-Pd(II) produced α-hydroxy ketone in moderate to excellent yield, while the oxidation of terminal alkene produced methyl ketone in moderate yield. So, both polymeric supported catalysts showed good to excellent efficiency. To enhance the solubility of the reactant, a polar aprotic solvent was chosen for the oxidation reactions in the presence of CuCl2 as a Pd(0) re-oxidant and in the presence of an acid to enhance the tautomerization of ketone to enol since the oxidation occurs on enol functional group, and the tautomerization of enol back to ketone which occurs during the oxidation of alkenes. The oxidation reactions were performed at room temperature.