Developing routes to produce cellulose nanocrystals (CNCs) from high-lignin wood residues is essential for expanding sustainable nanocellulose feedstocks. In this work, Meranti (Shorea sp.) sawdust was valorized into CNCs by integrating ammonium persulfate (APS) pretreatment with subsequent sulfuric acid hydrolysis. To establish a severity map and define an operating window, APS pretreatment severity was systematically varied by adjusting APS concentration and the sawdust-to-APS (solid-to-liquid) ratio, and its influence on CNC structural properties was evaluated. APS pretreatment partially disrupted and oxidized the lignocellulosic matrix, enabling acid hydrolysis to liberate crystalline cellulose domains. XRD analysis confirmed the preservation of the cellulose I crystalline structure, with a maximum crystallinity index of 72% at 2 M APS and a sawdust-to-APS ratio of 1:30 (w/v), and an average crystallite size of approximately 10 nm estimated using the Scherrer equation. SEM and TEM analyses revealed rod-like CNCs with smooth surfaces and relatively homogeneous dimensions. The optimized samples exhibited CNC lengths of 188.71 ± 5.01 nm and widths of 26.79 ± 1.72 nm. These results demonstrate that Meranti sawdust, a high-lignin wood residue, can be converted into structurally well-defined CNCs using a two-step APS/acid process without prior alkaline pulping or bleaching. This study clarifies the role of APS oxidation in enabling CNC production from feedstocks with lignin contents above 20% and provides a basis for valorizing Meranti sawdust as a renewable precursor for CNCs in advanced material applications.
The adsorption ability of Iraqi initiated calcined granulated montmorillonite to adsorb of 4-(4-Nitrobenzeneazo) 3-Aminobenzoic Acid from aqueous solutions has been investigated through columnar method. The azo dye adsorption found to be dependent on adsorbent dosage, initial concentration and contact time. All columnar experiments were carried out at three different pH values (5.5, 7and 8) using buffer solutions at flow rate of (3 drops/ min.), at room temperature (25±2) °C. The experimental isotherm data were analyzed using Langmuir, Freundlich and Temkin equations. The monolayer adsorption capacity is 6.4066 mg Azo ligand per 1g calcined Montmorillonite. The experiments showed that highest removal rate 90.5 % for azo dye at pH 5.5.The
... Show MoreIn this manuscript has investigated the synthesis of plasma-polymerized pyrrole (C4H5N) nano-particles prepared by the proposed atmospheric pressure nonequilibrium plasma jet through the parametric studies, particularly gas flow rate (0.5, 1 and 1.5 L/min). The plasma jet which used operates with alternating voltage 7.5kv and frequency 28kHz. The plasma-flow characteristics were investigated based on optical emission spectroscopy (OES). UV-Vis spectroscopy was used to characterize the oxidization state for polypyrrole. The major absorption appears around 464.1, 449.7 and 435.3 nm at the three flow rate of argon gas. The chemical composition and structural properties of the
... Show MoreAg nanoparticles were prepared using Nd:YAG laser from Ag matel in distilled water using different energies laser (100 and 600) mJ using 200 pulses, and study the effect of the preparation conditions on the structural characteristics of and then study the effect of nanoparticles on the rate of killing the two types of bacteria particles (Staph and E.coli). The goal is to prepare the nanoparticle effectively used to kill bacteria.
Chloroacetamide derivatives (2a-g) have been prepared through reaction of chloroacetyl chloride(1) (which prepared by the reaction of chloroacetic acid with thionyl chloride) with primary aromatic amines and sulfa compounds to afford compounds (2a-g) which then reacted with p-hydroxy benzaldehyde via Williamson reaction to obtaine the new compounds 2-(4-formyl phenoxy)-N-aryl acetamide (3a-g). Finally , compounds (3a-g) will be use as a good synthon to prepare the Schiff bases represented by compounds 2-(4-aryliminophenoxy)-N-arylacetamide (4a-g). through , reaction with some primary aromatic amine. All the prepared compounds were investigated by the available physical and spectroscopic methods.
This paper describes the application of consensus optimization for Wireless Sensor Network (WSN) system. Consensus algorithm is usually conducted within a certain number of iterations for a given graph topology. Nevertheless, the best Number of Iterations (NOI) to reach consensus is varied in accordance with any change in number of nodes or other parameters of . graph topology. As a result, a time consuming trial and error procedure will necessary be applied
to obtain best NOI. The implementation of an intellig ent optimization can effectively help to get the optimal NOI. The performance of the consensus algorithm has considerably been improved by the inclusion of Particle Swarm Optimization (PSO). As a case s
Abstract Additive manufacturing has been recently emerged as an adaptable production process that can fundamentally affect traditional manufacturing in the future. Due to its manufacturing strategy, selective laser melting (SLM) is suitable for complicated configurations. Investigating the potential effects of scanning speed and laser power on the porosity, corrosion resistance and hardness of AISI 316L stainless steel produced by SLM is the goal of this work. When compared to rolled stainless steel, the improvement is noticeable. To examine the microstructure of the samples, the optical microscopy (OM), scanning electron microscopy (SEM), and EDX have been utilized. Hardness and tensile strength were us
... Show MoreThis study intends to examine the efficiency of student-centered learning (SCL) through Google classroom in enhancing the readiness of fourth stage females’ pre-service teachers. The research employs a quasi-experimental design with a control and experimental group to compare the teaching readiness of participants before and after the intervention. The participants were 30 of fourth stage students at the University of Baghdad - College of Education for Women/the department of English and data were collected through observation checklist to assess their teaching experience and questionnaires to assess their perceptions towards using Google Classroom. Two sections were selected, C as a control group and D as the experimental one each with (
... Show MoreA simple and rapid spectrophotometric method for the determination of sulphite SO3-2 is described. The method is based on the rapid reduction of known amount of chromate CrO4-2 in the presence of sulphite in acidic medium of 2N H2SO4. The amount of excess of chromate was measured after it reactions with 1,5-diphenylcarbazide which finally gives a pink-violet, water soluble and stable complex, which exhibit a maximum absorption at 542 nm. Beer's law was obeyed in the concentration range from 0.004-6.0 µg of sulphite in a final volume of 25 ml with a molar absorbtivity of 4.64×104 l.mol-1.cm-1, Sandal's sensitivity index of 0.001724 ?g .cm-2 and relative standard deviation of ±0.55 - ±0.83 depending on the concentration level. The present
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