{"title":"Binary Nematic Liquid Crystals Mixture with Enhanced Electro-Optics Properties for Photonic Applications","authors":"Ghada Hassanein, Omaima Alhaddad, Mostafa Ellabban","doi":"10.47604/ajps.2562","DOIUrl":"https://doi.org/10.47604/ajps.2562","url":null,"abstract":"Purpose: In this work, we mix two simple nematic liquid crystals (NLCs) and investigated the binaryNLCs mixtures of 7CB/PCH5 of different mixing ratios. \u0000Methodology: The pure liquid crystals 7CB and PCH5 and binary mixtures of them of high temperature stability were thermally analyzed by differential scanning calorimetry. The mixture 7CB/PCH5:30/70 wt% has the highest thermal stability with a nematic-isotropic (N-I) transition temperature at 50oC. The electrooptic properties of 7CB, PCH5, and the mixture 7CB/PCH5:30/70 wt% at room temperature were also investigated using an amplitude modulated electric signal (1 kHz - 100 Hz) by increasing diving peak voltage from 0 V to 10 V. The threshold volage is relatively reduced for the binary mixture in comparison to that value for PCH5. In comparison to the pure LCs, the mixture 7CB/PCH5:30/70 wt% has the fastest response times of values 2.36 ms total time response, 0.41 ms rise time, and 1.95 ms fall time. It has also the highest contrast ratio. Moreover, it has a maximum measured transmission that is higher than those for PCH5 and 7CB by about 17 % and 8%, respectively, at a field strength of 2V/mm. \u0000Findings: The obtained results indicate that the electrooptic properties of PCH5 was improved when mixed with a proper ratio of 7CB, of lower cost, more stablity , and higher potential for photonic applications. \u0000Unique Contriburibution to Theory, Practice and Policy: This expermental study shows that simply by mixing two relatively low cost NLCs materials, one of high thermal stability and low electro-optic properties with other one of low thermal stability and better electro-optic properties; this would improve the stability, response, and transmition of the binary mixture. If the a suitable driving method is applied, without doping with other orgnic or inorganic matrial.","PeriodicalId":495586,"journal":{"name":"American Journal of Physical Sciences","volume":"30 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141118920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sajid Ullah, Ayesha Gulnaz, Saeed Anwar, Arif Kamal, Husna Wali
{"title":"Synthetization and Characterization of Zinc Oxide Nanoparticles by X- Ray Diffractometry (XRD), Fourier Transforms, Infra-Red Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and Antibacterial Activity Test","authors":"Sajid Ullah, Ayesha Gulnaz, Saeed Anwar, Arif Kamal, Husna Wali","doi":"10.47604/ajps.2294","DOIUrl":"https://doi.org/10.47604/ajps.2294","url":null,"abstract":"Purpose: Nanomaterials with their derivable potentials offer wide obtain ability and have recently aroused much attention for biomedical applications. Nowadays, nanomaterials-based colorimetric sensing is a quickly emerging field of sensing applications. Nanomaterials are considered as the main component of colorimetric determination of hydrogen peroxide to replace the natural enzyme-based sensors because of some associated intrinsic drawbacks. Considering the advantageous properties of ionic liquid (IL) for various applications, significant attention has been made to the use of ionic liquid stabilized metal NPs which may serve as a regulator to enhance the catalytic performance of the metal nanoparticles in the different IL reaction medium. \u0000Methodology: The peroxidase-like activity of IL coated metal NPs (IL-MNPs) have been considered for the catalytic oxidation reaction of chromogenic substrate 3,3,5,5- tetramethylbenzidine (TMB) in the presence of H2O2 at an estimated wavelength of 652 nm. \u0000Results: The synthesized metal nanoparticles (Ag) were produced using a chemical reduction method. Various characterization techniques like FTIR, UV-Visible spread Reflectance Spectroscopy [UV-VIS DRS], were employed, which verified the structure, nano-size and successful combination of metal dopant ion into the samples. The molecular structure of ionic liquid with varying cations was produced and confirmed by 1H-NMR spectroscopy. The ionic liquid was coated on metal nanoparticles to enhance their conductivity. \u0000Unique Contribution to Theory, Practice and Policy: Optimized reaction conditions like pH, temperature and catalyst dosage affect catalytic activity and color sensing properties. The coating of [Min] Ac on Ag achieved low detection limits and colorimetric detection of [Pyr] based Ag.","PeriodicalId":495586,"journal":{"name":"American Journal of Physical Sciences","volume":"81 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140484584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jean Kepdieu, Chantale Djangang, Jacques Njimou, Gustave Tchanang, Cyprien Ekani, Sanda Maicaneanu, Chedly Tizaoui
{"title":"Theoretical and Experimental Study of the Adsorption of Natural Red 4 Dye from Synthetic Aqueous Media Using a Low-cost Silica-smectite Composite","authors":"Jean Kepdieu, Chantale Djangang, Jacques Njimou, Gustave Tchanang, Cyprien Ekani, Sanda Maicaneanu, Chedly Tizaoui","doi":"10.47604/ajps.2137","DOIUrl":"https://doi.org/10.47604/ajps.2137","url":null,"abstract":"Purpose: A study of the removal of dye Natural red 4 (NR4) by a low-cost silica-smectite clay labeled SSC was carried out.
 Methodology: Batch tests were carried on with some processing parameters namely initial dye concentration (10 - 50 mg/L), temperature (25 – 65 °C), adsorbent dose (1 – 5 g/L), initial pH (4 – 8) and contact time (0 - 120 min).
 Findings: The Energy of adsorption was less than 20 kJ/mol showing a physisorption process. Also, thermodynamics parameters such as enthalpy of activation ∆H* (19.0 kJ/mol), entropy of activation ∆S* (- 024 kJ/mol/K) and Gibbs free energy of activation ∆G* (90.57 - 100.17 kJ/mol) revealed that the adsorption of NR4 molecules onto SSC was endothermic and with no significant changes in the internal structure of the adsorbent. The pseudo-first order and pseudo-second order had a good correlation with experimental data with R2 = 0.99 and R2 = 0.98 respectively. Langmuir isotherm model matched well the equilibrium data with a maximum adsorption capacity Qm of 25.55 mg/g. and a correlation value of 0.98.
 Unique Contribution to Theory, Policy and Practice: The newly synthesized and characterized low-cost silica-smectite composite is effective in the adsorptive removal of natural red 4 dye from water wastes.","PeriodicalId":495586,"journal":{"name":"American Journal of Physical Sciences","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135253761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}