List of Articles Crystallinity

• Open Access Article
  • Abstract Page
  • Full-Text
  
  1 - Extraction of Hemicellulose and Lignin from Sugarcane Bagasse for Biopolymer Films: Green Process
  Sifiso Nkosi Krishnan Kanny
  Manuscript profile
• Open Access Article
  • Abstract Page
  • Full-Text
  
  2 - A study on the structural and textural properties of medium-silica ZSM-5 templated by ethanol
  Mohadese Nazari Fereydoon Yaripour
  10.30495/jacr.2021.686092
  Templates play a key role in the crystallization of zeolites. Quaternary ammonium compounds, the most common templates used in the synthesis of ZSM-5 zeolite, can cause problems in large-scale production due to their high cost, toxicity, and corrosive effects. The prese More

  Templates play a key role in the crystallization of zeolites. Quaternary ammonium compounds, the most common templates used in the synthesis of ZSM-5 zeolite, can cause problems in large-scale production due to their high cost, toxicity, and corrosive effects. The present study aimed to synthesize the medium-silica ZSM-5 templated by ethanol in a 5-liter stirred autoclave (450 rpm) with cheap and available alumina and silica sources. The effects of synthesis and operating parameters on the structural and textural characteristics of the zeolite were investigated using XRD, FTIR, FE-SEM EDX, XRF, BET, and TGA analyses. The results showed that the small size of ethanol and its weak bonding with Si-OH terminal groups of silicate anions increased the crystallization time and the sensitivity of the structure to synthesis parameters. However, proper adjustment of these parameters allowed the synthesis of a pure ZSM-5 with high crystallinity and surface area. It was found that high OH-/SiO2 ratios decrease the aspect ratio Lc/La by increasing nucleation rate and decreasing crystal growth. Moreover, increasing the Si/Al value accelerated the kinetic growth of the crystal in the b axis and led to the appearance of twinned coffin-shaped crystals. Finally, a pure silica-medium ZSM-5 (SiO2/Al2O3 = 50) with a yield above 90%, relative crystallinity of 100%, and surface area of 443 m2.g-1 was obtained at OH-/SiO2 =0.15 within 40 h. Manuscript profile
• Open Access Article
  • Abstract Page
  • Full-Text
  
  3 - Continuous and controlled production of dexamethasone nanoparticles in a microfluidic system
  payam zahedi maryam tabatabai morteza fathi pour amin sohrabi
  The aim of this work is to produce continuously dexamethasone nanoparticles (DEX NPs) in a microfluidic (MF) system via nanoprecipitation method to control particle size, possessing their physical structure, and enhancing the efficiency of this hydrophobic drug in physi More

  The aim of this work is to produce continuously dexamethasone nanoparticles (DEX NPs) in a microfluidic (MF) system via nanoprecipitation method to control particle size, possessing their physical structure, and enhancing the efficiency of this hydrophobic drug in physiological environments. In order to fabricate a MF chip, a series of microchannels with dimensions 1 cm in length, 200 μm in width, and 50 μm in depth are embedded using ultraviolet soft lithography on a sheet based on polydimethylsiloxane (PDMS), and then the laminar fluid flow ability is investigated through it. The effective factors on the optimized production of the drug NPs are determined by the design of experiment. In this line, the optimum values for drug solution concentration, surfactant concentration, drug solution flow rate, and non-solvent flow rate are 15 mg/ml, 1 mg/ml, 4.5 ml/h, and 8 ml/h, respectively. By adjusting these values the average sizes of DEX NPs are obtained 590 ± 20 nm based on the model and 500 ± 20 nm according to the experiments. In the following, the results of dynamic light scattering (DLS) test show the narrow size distribution of DEX NPs fabricated using the MF chip. Also, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) assays reveal that application of the MF system does not affect the crystallinity of the drug NPs and does not alter their structure after the process. Finally, MF-assisted DEX NPs sample shows the drug solubility rate of about 8-fold compared to the commercial powder ones Manuscript profile
• Open Access Article
  • Abstract Page
  • Full-Text
  
  4 - Effect of silver nanoparticles on the crystallinity of polyethylene
  مریم ابارشی سکینه مسگر شاهرودی
  In the current research, the effect of silver (Ag) nanoparticles on the crystallinity of polyethylene was investigated. For this purpose, Ag nanoparticles were synthesized using chemical reduction method and characterized by X-ray diffraction (XRD), UV–visible spe More

  In the current research, the effect of silver (Ag) nanoparticles on the crystallinity of polyethylene was investigated. For this purpose, Ag nanoparticles were synthesized using chemical reduction method and characterized by X-ray diffraction (XRD), UV–visible spectroscopy, and transmission electron microscopy (TEM). The mean particle size of Ag NPs was determined about 21.7 nm. The polyethylene-silver Nano composites (PESNs) containing different Ag contents (5, 10, 20 and 30 wt%) were fabricated by mechanical milling method. After the characterization of samples by XRD and scanning electron microscopy (SEM), effect of Ag nanoparticles on the crystallinity of polyethylene was investigated by Nara and Komiya method. Results show that the crystallinity of polyethylene increases from 63.64% to 77.67% as Ag NPs content increases from 0 to 30%. Manuscript profile