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Go to Editorial ManagerMagnesium oxide nanoparticles were deposited by laser pyrolysis process. Three types of lasers were employed CW CO2, Q-switched Nd-YAG (short pulses) and long pulses Nd-YAG lasers. The size and density of nanoparticles vary with laser energy, power, pulse duration and the scanning speed of the laser. In this method, MgO nanoparticles were deposited by a laser beam on a quartz substrate from aqueous solution of magnesium nitrate. AFM images reveal formation of small nanoparticle size of 24.5 nm with surface roughness 6.97nm by Q-switched Nd-YAG laser (10 ns) when the energy was 1J. While for CO2 laser, the smallest size was 18.8 nm at 0.4mm/s scanning speed with surface roughness 5.21nm at the same scanning speed. Moreover, long Nd-YAG pulses laser produces relatively larger average size of 37.5nm at 0.8ms pulse duration. The absorption spectra from UV-Visible spectroscopy were also conducted. The best absorption intensity was obtained at a wavelength ranging between 420-430 nm for both lasers. Finally, Thermal analysis using COMSOL Multiphysics software for the deposition process reveals that maximum temperature about 440Kfor Q-Switched Nd-YAG laser at 1J laser energy. While for RF CO2 laser, the maximum temperature obtained at 0.4mm/s scanning speed is 850K.This work provides a good knowledge for the deposition of nanoparticles using laser beams.
Two lasers were utilized for silicon processing using photoelectrochemical etching and laser texturing in order to produce nano/micro structures, respectively. Photoelectrochemical etching process utilizes a CW diode laser of 532 nm wavelength was used to support electrochemical etching for both n-type and p-type conductivity. While laser texturing process was employed using pulsed fiber laser of 1064 nm wavelength. Various characterization methods were devoted to examine silicon micro/nanostructures surfaces produced by lasers. These methods include AFM, SEM and Raman scattering to provide clear evidence about formation of micro/nanostructures abundant at silicon surfaces. Moreover, FTIR analysis for the laser produced silicon surfaces could emphasize whether the resultant silicon surface is hydrophilic or hydrophobic. Image analysis software adopted a side view micro image was used to measure the contact angle between the water droplet and silicon micro/nano-surfaces. It is found that the laser produced silicon nanostructure by photoelectrochemical etching creates a hydrophobic surface and even super hydrophobic with contact angle of 130 degrees for 50 nm average size. In addition, utilizing fiber laser of high repetition rate for laser texturing produces microstructures that are super hydrophilic with contact angle could reach 8 degrees for a surface dimension of 50 μm.
The aim of the research was for evaluation the morphological and chemical alterations that result from the Nd:YAG laser treatment of dental enamels using optical microscopy (OM) with Energy dispersion X-ray spectroscopy (EDX), respectively. Two human enamel samples were obtained, the samples were exposed to the Nd: YAG laser irradiation. The micrographs obtained by optical microscopy demonstrated morphological changes. The concentrations of carbon (C), calcium (Ca), phosphorus (P), and oxygen (O) in crater sites and its environs were measured using EDX, as well as trace amounts of manganese, magnesium, and silicon. However, due to their low concentration, these trace elements were neglected. We obtained the maximum depth profile of carters on tooth enamel surface at 1200 µm with laser pulse of 532 nm with 500 mJ energy/pulse, while the minimum depth profile of carters at 200 µm with laser pulse of 1064 nm with 100 mJ energy/pulse. Dental tissue can be safely treated with a Nd: YAG laser with 200 mJ, 9 ns, and 1064 nm since this laser irradiation range did not induce any noticeable morphological changes. As a result, the Nd: YAG laser offers as an ideal option for clinical treatment.
Many difficulties were recorded during laser-assisted tattoo removal. But most of them remain unknown. The recent literatures on laser tattoo removal focuses more on removal methods and systems than on side effects, such as temperature increase over tissue and ideal treatment parameters. This study aims to assess the surface temperature in compliance with eyebrow tattoo removal. The study was carried out for 55 patients aged between 22 and 43 years. The treatment was performed using a Nd:YAG laser (1064nm, Phi laser system) with an energy of 1000 mJ, a frequency of 3Hz, and a spot size of 8mm. The surface temperature of the skin during tattoo removal process was measured with a FLIR thermal camera. The results were analyzed by testing the normal state of distribution. The Shapiro-Wilk and Kolmogorov-Smirnov tests were used. All patients finished the full treatment of three laser sessions to achieve the goal of total removal. After temperature comparison, the results showed a significant influence of skin nature and patients' age on temperature distribution on skin, as for older patients, the energy absorption increased. Additionally, patients with darker skin tones exhibited greater absorption. The benefit of deepening understanding appeared in the Temperature distribution in the tissues of the affected area and the surrounding area during laser irradiation, as it provides a guiding and reference function for the effect of photothermal therapy.
Optical methods are widely used for medical diagnostic and therapeutic purposes. The use of laser source as non-ionized radiation in the imaging is considered safe, and has advantages more than the other radiological methods The laser application in imaging is based upon the detection and measuring the laser light parameters after passing through the turbid media of the tissue layers and the tumor mass to differentiate them precisely according to their different optical properties._x000D_ In this experimental study, the tumor masses were implanted in the legs of ex-vivo mice. Then each leg was non-invasively scanned by NIR 785nm diode laser. The penetrated laser light power through the leg was measured. The results were tabulated and treated by using the Matlab program version R2013a (8.1.0.609) to create 2D image for the scanned tissue. The resulted images were clear. They showed precisely the imbedded tumor, its dimensions, and its location inside the tissue.
Low Level Laser Therapy (LLLT) is one of biotechnology its useful as produced treatment for diseases that were previously difficult to treat. Some studies claim that an improvement in hearing threshold and tinnitus symptoms by Low Level Laser therapy and others set no significant effect of laser treatment. The aim of this project was to evaluation effect of low level laser (LLLT) treatment on senserinurail hearing loss. The study including 16 patients divided into two groups each group consists of 8patients (first group consist of 14 ear and second group consist of 16 ears), and each group has ?=650nm+532nm and 2.78mW/cm2. The result of this project found statistically significant differences in each group ( before and after laser application) as well as a significant change in the threshold of pure tone audiometry for patients having hearing degree (40-75)dB in each group.
Laser annealing represents a powerful method for tailoring the properties of silver nanofilms on quartz substrates, offering advantages in terms of precision, scalability, and functionalization. Continued research efforts are expected to deepen our understanding and broaden the applications of this promising technology in diverse fields. In this work, laser annealing of silver nanofilms deposited on quartz substrates was performed and investigated. RF CO2 laser of variable power in the range 1–20 W with beam quality of 1.1 was used to anneal silver nanofilms. AFM analysis emphasized that nanocrystal sizes of 60 nm were obtained for silver nanofilms. Furthermore, the optimum absorbance peak occurred at about 449 nm for smaller film thickness. Thermal simulation and analysis of the annealing process were also conducted using COMSOL Multiphysics software. It was observed that optimal temperature of 729 K was achieved when 10 W laser power and 2 mm/s scanning speed were used to anneal 20 nm silver film thickness. Design of expert analysis was also used to better understand the laser annealing process of silver nanofilms since convolution of several process parameters affect the process output.
Desired mechanical properties like microstructure, micro hardness and wear resistance are the key parameters for which low carbon steel (AISI 1006) are widely selected. Surface heat treatment applied to improve these properties; traditionally surface heat treatments like induction hardening, in recent time’s laser surface hardening. In this work, thermochemical treatment (liquid nitriding) by using mixture from 61% NaCN, 15% K2CO3 and 24% KCL and followed by Nd:YAG laser surface treatment was done . The laser parameter were energy (0.89, 2, 4 and 9) J, spot diameter (0.790 ,0.33, 0.283 and 0.224) mm, pulses duration (1, 2.33, 4.47 and 9.87) ms with fix wavelength 1604nm. Laser surface treatment cycle was melting the layer surface, holding and rapid cooling in air medium. Optical microscopy (OM) and scanning electron microscope (SEM) has been used to study the microstructures and cross-sectional of molted and heat affected zones respectively. The wear test was done to measure the wear rate by using pin -on-disk principles were satisfied. The result shown that increasing in laser energy effects to increase in the area of melted and heat affected zones of nitriding steel. Also increasing in laser energy led to increase micro hardness about 61%, while wear rate decrease about 40 % and increased depth of molted zone.
Photonic crystal fibers (PCFs) are generally divided into two categories: solid-core photonic crystal fibers and hollow-core photonic crystal fibers. In this paper, a long-period fiber Bragg grating (LPFBG) was experimentally fabricated in a hollow-core photonic crystal fiber (HC-PCF) using a CO₂ laser and based on the point-by-point technique. Proper LPFBGs were inscribed using laser powers of 0.9 W and 1.4 W, with grating parameters (grating period, length of each pitch, and depth of each pitch) equal to (136 µm, 48.042 µm, 16 µm) and (142 µm, 74.027 µm, 22.09 µm), respectively, for two samples. The Bragg wavelengths and full-width at half-maximum (FWHM) were (1529.274 nm, 1.34 nm) and (1529.629 nm, 5.11 nm), respectively, for the two samples fabricated using CO₂ laser powers of 0.9 W and 1.4 W. From these results, it was recognized that the optimal LPFBG-HC-PCF was the one fabricated using 0.9 W laser power. The unique structure of hollow-core photonic crystal fibers, which enables light propagation within the air core and provides a large internal surface area, has attracted significant research interest for various sensing و communication applications, Environmental and Biological Monitoring, and medical applications.
This review study emphasizes the significance of MoS2 nanomaterials, their manufacture, and their applications. This review examined nanomaterials and their generation processes, concentrating on laser ablation and nanomaterial production. This study advances nanomaterial synthesis and helps discover new applications by explaining the fundamental concepts and aspects affecting synthesis. Future studies should optimize laser settings, explore novel precursor materials, and understand laser-induced MoS2 synthesis pathways to enable customized nanomaterial design and engineering.
Enhanced signal emission from nano (ESEN) coated titanium target over than that from normal untreated one was investigated. Four samples of Ti alloy were adjusted, the first sample was left untreated, the second and third samples were coated with plasma sputter at thicknesses of 35nm and 70nm, and the last sample was treated with a drop of colloidal Au nanoparticle solution prepared by laser ablation. The (ESEN) was monitored with Ti at 413.7 and 393.3 nm. It was obtained that the spectral emission from the nano-laser ablation had a greater improvement than that from the plasma sputter coating or bulk target. Enhancement factors were found up to ten folds, and show the spectroscopic line induced patterns by laser energies (100,150, and 200mJ) from the alloy with and without gold.
Three-dimensional reconstruction of real objects comprises capturing the appearance and the shape for these objects and determining the three-dimensional coordinates for their profiles. This reconstruction process can be accomplished either by using active or passive techniques. In this paper, a new fusion method is proposed for 3D reconstruction. This method exploits the advantages of both stereo-based passive and laser-based active techniques and overcomes their limitations to improve the performance of 3D reconstruction. With this method, a hybrid laser-based structured light scanning system is designed and implemented. This system captures the required information using passive and active techniques and uses the proposed fusion method for 3D reconstruction. The performance of the proposed method and its scanning system were experimentally evaluated. The evaluation results show high reconstruction performance for the proposed fusion method over the traditional 3D reconstruction techniques. The results also show the effectiveness of the hybrid laser scanning system and its ability to scan and reconstruct the shape and the appearance for real objects using the proposed fusion method.
In this work, four fiber Bragg gratings are fabricated by infiltration different volumes of liquids (star line Glass Mechanix optical adhesive material, olive oil diluted with ?ethanol) into the hollow core photonic crystal fibers (HC19-1550 (Thorlab Company)). The amplitude splitting interferometric technique with a high resolution specially designed translation stage was used for the fabrication process. This stage is capable of moving the fibers in micrometer ?resolution steps. The fabrication was carried out using blue laser operated at wavelength of 405 nm. The infiltrated four photonic crystal fibers were exposed to the blue laser beam of 405 nm forming periodic fringes for Bragg grating generation. These fringes were generated from the interference of two splitted laser beams. All fabricated fibers have the same Bragg length of 3.8 cm and average gratings periods of 0.224 ?m. The four fibers were analyzed by an optical microscope which displayed the areas that were cured using blue laser. The fabricated fibers also were tested by putting laser beam at one end of the fiber and determining the transmittance at the other fiber end by optical signal analyzer? (Thorlabs-CCS200). The resulted Bragg grating fibers have 653.3 nm Bragg reflected wavelength. The results also showed that fiber with higher volume of olive oil has the highest reflection peak about ?96.09647 %? with the greatest FWHM (full width at a half maximum) ?about 0.74 nm.In addition, three of the fabricated fibers (B, C and D) that contained olive oil were prepared for testing magnetic field sensor. The results show that all the fibers shifted to near infrared range. The results also showed that fiber with higher concentration of olive oil has the greatest magnetic wavelength shift about 653.4 nm, the highest fiber sensitivity about ??0.000494623656 nm/ Gauss?, the highest reflection peak about 96.91827? %, and the greatest FWHM ?about 0.98 nm.
Cancer is a disease caused by uncontrollable cell growth and division. Surgery, chemotherapy, radiotherapy, and hormonotherapy are all cancer treatment options. In addition to noninvasive cancer ablative therapy. As an example, ultrasonic therapy, even with low-intensity pulsed ultrasound (LIPUS) or high-intensity focused ultrasound (HIFU), and Laser therapy (photo-biomodulation therapy) in low-level laser therapy (LLLT) with different wavelength ranges from ultraviolet (UV), visible and infrared (IR) that all have demonstrated different results depending on the target of treatment so previous trials therapies are being studied. This paper reviews recent studies on the in vitro treatment effect of ultrasound therapy and laser therapy on normal and cancerous cell lines with specific parameters. The effect of ultrasound results showed a decrease in cell proliferation and an increase in apoptosis in different types of cells, depending especially on sound intensity, known as Special Peak Temporal Average Intensity (ISPTA). While the laser effect is noticed on cell viability, either enhance or inhibit their viability depending upon the dose of exposure and other specific parameters like wavelength, energy density, and power density used in each treatment protocol. The previous studies conclude that each response would have a treatment method with specific parameters, even an increase or decrease in cell viability. Further studies need to be applying these methods in vivo.
One of the unique properties of laser heating applications is its powerful ability for precise pouring of energy on the needed regions in heat treatment applications. The rapid rise in temperature at the irradiated region produces a high temperature gradient, which contributes in phase metallurgical changes, inside the volume of the irradiated material. This article presents a comprehensive numerical work for a model based on experimentally laser heated AISI 1110 steel samples. The numerical investigation is based on the finite element method (FEM) taking in consideration the temperature dependent material properties to predict the temperature distribution within the irradiated material volume. The finite element analysis (FEA) was carried out using the APDL scripting language (ANSYS Parametric Design Language) that is provided by the commercial code ANSYS. Infrared (IR) thermography technique was used to explore the workpiece surface and to validate the obtained results. The work takes into account the effect of different speeds of the laser beam and pulses overlap on the temperature pattern of the material surface and depth.
This research focuses on enhancing the diagnostic power of the slit lamp, a fundamental ophthalmic instrument, by replacing its traditional halogen light source with a cutting-edge white laser. The objective of this modification is to significantly improve the brightness, intensity, and color accuracy, which are crucial for distinguishing fine ocular details during eye examinations. White laser technology offers a more stable, energy-efficient light source with reduced maintenance needs, making it a valuable upgrade over conventional systems. As part of this redesign, the optical system will be optimized with new filters, lenses, and heat management techniques to accommodate the white laser. Additionally, integrating a high-resolution digital camera with the enhanced illumination system is expected to provide sharper, more accurate imaging for better diagnosis. The anticipated outcome is a transformative improvement in ocular diagnostics, leading to earlier and more precise detection of eye conditions. This advancement holds promise for both patients, through better care, and ophthalmologists, through increased diagnostic efficiency. Challenges in implementation and potential solutions are also considered.
In our work, three internal regions of rat are exposed to four different lasers with different power density, and then studying the histology of the tissues. Together the total absorption and transmission of the tissues at certain wavelength were determined.Changing the wavelength across the absorption peak caused a significant difference in laser tissue interactions and changing the absorption coefficient, relaxation time, generated heat, and the intensity as a function of penetration depth. Furthermore, little mechanical damage could be seen in conventional histology.
Super-hydrophobic is the tendency of a surface to spit out water droplets. Only a surface with high apparent contact angle (>1500), low contact angle hysteresis (<100), low sliding angle (<50), and strong Cassie model state stability is considered a super-hydrophobic surface. In an attempt to create highly hydrophobic synthetic surfaces suitable for a range of uses, attempts have been made to mimic the super-hydrophobicity found in natural materials (such as lotus leaves). Due to its wide range of applications including waterproof, anti-fog, anti-ice and anti-corrosion surface, the laser processing process achieved the use of process parameters which had a significant impact on the roughness factor. High roughness factor F. At constant values of p = 3 mW and ω = 10 μm, at scanning speeds of 6000 mm/s.
Surface reconstruction of silicon using lasers could be utilized to produce silicon nanostructures of various features. Electrochemical and photoelectrochemical etching processes of silicon were employed to synthesize nanostructured surface. Effects of current densities 5, 10 and 20 mA/cm2 on the surface features were examined. It is found that the surface porosity and layer thickness increase with the current density. Moreover, large surface area of 410 m2/cm3 can be achieved when laser power density 0f 0.6 W/cm2 was used during the etching process. Optimum operating conditions were found to achieve better silicon nanostructured surface features. The surface roughness can be reduced to 8.3 nm using laser beam of 650 nm irradiated the silicon surface during the photoelectrochemical etching process. The surface morphology of the nanostructured silicon surface using SEM and AFM could give rich details about the surface. Silver nanoparticles of 10 – 20 nm was embedded at the nanostructured silicon surface by LIFT process to reduce the surface resistance and maintain the large surface area. This technique enables silicon nanostructures to be efficiently used in many optoelectronic applications.
This paper provides a comprehensive overview of microfluidic device (MFD) manufacturing processes. The review starts with an introduction elucidating the significance and advantages of MFDs. Subsequently, a brief description of the materials employed in MFD fabrication is presented. The manufacturing process used to create MFDs is then thoroughly examined, with a focus on the application of laser technology.
Diabetes is a long-term medical condition that impacts the way your body converts food into energy, it has the potential to lead to several severe health complications, such as heart disease, stroke, vision impairment, kidney issues, and nerve damage. Nevertheless, individuals with diabetes can lead extended and healthy lives with effective management. The goal of diabetes treatment is to keep your blood sugar levels within a healthy range. So Glucose measurement is an important part of diabetes management. It allows people with diabetes to track their blood sugar levels and make adjustments to their diet and medication as needed. Morning fasting blood glucose typically falls within the range of (70 mg/dL) to (110 mg/dL), while after a meal, blood glucose levels should ideally be below (140 mg/dL). In this proposed work an Arduino-based noninvasive glucose measurement device is proposed. Non-invasive glucose measurement devices do not require the user to prick their finger to draw blood. A Red Laser (RL) technique, is employed, this method surpasses the other invasive approach and non-invasive methods in terms of superiority. Since invasive techniques can be painful and expensive. This paper describes a new way to measure blood sugar levels without having to prick your finger. The method uses a red laser to shine light through the skin and measure how much the light is bent. The amount of bending tells the device how much sugar is in the blood. Numerous tests and experimental outcomes have been produced to demonstrate the exceptional accuracy of the proposed method.
In the field of engineering, 3D printers are indispensable due to their high precision. This study focuses on the construction and optimization of a 3D printer using aluminum T-slotted bars for the frame, Raspberry Pi 4 for control, and Lightburn software for image printing and machine control. After assembling the main components and programming with Marlin firmware, the machine was tested for vibration and noise reduction. The research compared the vibration of a diode laser and spindle during printing, revealing significantly lower vibration with the laser compared to the spindle. These findings demonstrate the effectiveness of the constructed 3D printer in reducing vibration and noise during operation.
This work describes seam welding process using dissimilar ferrous metals by pulsed Nd:YAG. The main objective of this work is to achieve the best welding conditions. This imposes careful selection for the welding parameters and inevitably the well design of experiment (DOE). Sheets of ASTM A240/316L stainless steel to ASTM A570/Gr30 carbon steel all of 0.5 mm in thickness were lap welded. Different pulse energies or the related peak power, pulse duration, pulse repetition rate, and welding speeds were used. Moreover, different welding speeds were controlled by the employed manipulator. The laser beam spot diameter and the standoff distance were fixed. Experimental results are supported by the computational 2D and 3D models. In this article response surface methodology (RSM) was applied to design the experiment and obtain the best parameters through a set of mathematical models that define the weld characteristics. The results show that the best joint in term of joint strength is obtained at 31.9 J pulse energy (related to 5.5 kW peak power and 5.8 ms pulse duration), power density of 1.43×106 W/cm2, 1.5 Hz pulse repetition rate, and 0.5 mm/s welding speed.
Cascade single mode-No Core - single mode fiber structure (SNS) optical filters have garnered a lot of interest as dependable optical devices. These devices' simplicity, compactness, affordability, all-fiber design, low transmission loss, and ability to continuously adjust the laser wavelength at a particular spectral range contribute to their dependability. The operation's foundation is multimode interference (MMI) and self-image phenomena. SNS filter based on optimized 4th self-imaging condition for different NCF- Specifications was theoretically optimized a tunable filter based on a cascade single mode-no core-single mode (SNS) fiber structure encircled by Ferrofluid was experimentally investigated. The findings indicate that reducing the NCF diameter can enhance the filter's tunability. device has applications in fiber laser technology, spectroscopy, and optical communication.
Recently microwave photonic filter (MPF) have a great interest due to their advantages which include low loss, wide bandwidth tunability, reconfigurability, and no electromagnetic interference. This paper presented a comprehensive optical transmission analysis of a reflective-type microring resonator (R-MRR) using coupled mode theory, and design guidelines for MPF through two cascaded R-MRR using COMSOL software simulation results. The design was implemented on silicon-on-insulator (SOI) platform-based MPF which exhibits wide bandwidth tunability and reconfigurability by adjusting the coupling coefficient in the two coupling regions. In this structure, a grating coupler (GC) reflector is introduced to the drop port of MRR. The analysis and simulation results were confirmed by utilizing a GC reflector and Mach-Zehender Interferometer (MZI). The results of the proposed MPF at laser light input of (1.55*10^6- m) wavelength showed the bandwidth and center frequency are adjusted from 0.3 to 6 GHz and 13 to 54.8 GHz, respectively, with a high rejection ratio reaching 70 dB. Overall, the structure represents a significant step towards designing the MPFs, which show perfect flexibility and have numerous applications in such fields as radar, sensor, and wireless communications.
Porous Silicon (PSi) samples with (100) orientation n-type were prepared by photo-electrochemical etching process for different variable parameters and fixed electrolyte solution HF:C2H5OH:H2O (2:3:3). Physical and optical properties of PSi would be varied with the variation of process parameters such as current density, anodization time and laser wavelengths. Two types of 50 mW diode lasers were chosen, 473 nm Blue & 532 nm green at 20 mA/cm2 & 15 min etching time to assist the iodization process. The band gap of the fabricated layer has raised up to (2.9 eV) which is more than twice its original value for the c-Si (1.12 eV). _x000D_ Exploiting the obtained gap energy values, the refractive index of porous silicon layer was calculated depending upon Vandamme empirical relation. It was observed that the porosity is modifiable through etching conditions, which in turn makes refractive index also modifiable. Thus, the calculation depended on taking certain parameters as the current density and etching time in order to compare the effect of applying the two laser wavelengths. AFM was applied to observe the homogeneity and roughness of the PSi mono-layer. The results are in a very good agreement with the range of the refractive indices of PSi and the illumination with green laser gives a better conclusion to use in solar cells as a good absorber and a bad reflector.
Whispering Gallery Mode Micro-Resonators (WGMRs) have received significant interest due to their great sensitivity to environmental changes, compact size, and ability to operate over a wide spectral range because their low optical losses produce high-quality factors so that they can be used in various sensing applications. This work investigates the design and implementation of cylindrical WGMRs for Refractive Index (RI) sensing for different delivery fiber diameters. Single Mode Fiber with different waist diameters (80,67.1,18) µm were used as delivery fibers. At the same time, the sensor (resonator) fiber is SMF with a diameter (125 µm). Quality factors and Free Spectral Range (FSR) were calculated and analyzed for each diameter. The quality factor for all diameters was in power of 104, which is considered good. The FSR is inversely proportional to fiber diameter. FSR values were (0.678,1.75,2.03) nm for (80,67.1,18) µm delivery fiber diameters respectively. An analyte prepared by NaCl with different refractive indices is used to investigate the RI sensor performance. Higher sensitivity is obtained from the WGMR with a smaller waist diameter, which is (-)74 nm/RIU. While for the delivery fiber diameters (80,67.1) µm were (-0.28, -9.27) nm/RIU respectively. The submitted sensor will have a good contribution in the field of chemical, biological and medical applications.
The recent progress in integrated photonics has promoted microwave photonic filter (MPF) technologies to a supreme level to develop wireless, radar, and internet communication systems. Therefore, the specifications that distinguish the MPF chip include small size, low power, and inexpensive. The MPF that utilized these technologies has demonstrated the merit of wide frequency tuning and reconfiguring by selecting the desired spectral content and rejecting the sideband signals furthermore the immunity to electromagnetic interference. This paper reviews recent techniques involved in microwave filter design on multiple platforms, which involve cascaded micro-ring resonator (MRR), ring-assisted Mach-Zehender-Interferometer (MZI) coupler, Brillion-active waveguide, reflector-type MRR, and Bragg grating with phase shifts. In particular, we demonstrated the output characteristics of the microring integrated with a Mach–Zehnder interferometer coupler technique.
This study simulates a free-space optical communication system that uses optical beams with varying responses to atmospheric disturbances to secure transmitted data. Atmospheric turbulence was modeled with high accuracy to replicate real-world conditions closely. Non-diffracting beams were generated and used to represent optical beams and compared in two scenarios, conventional data transmission, and optifusion data protection. This approach facilitated a comprehensive analysis of the transmission environment and the effectiveness of optifusion, identifying the most suitable non-diffracting beam types for secure data propagation. By analyzing the values of key performance metrics of the selected non-diffracting beams across different weather conditions and long propagation distances, the study demonstrated the simulation system's reliability and the optifusion method's effectiveness in enhancing data security. The results showed that non-diffracting beams resist atmospheric turbulences strongly, emphasizing their potential for secure, long-range free-space optical communications.
The fifth generation (5G) and beyond mobile networks support increasing number of users with increasing bit rate per users. This has encouraged researchers to propose coherent digital subcarrier multiplexing (SCM) point-to-multipoint (P2MP) architectures to reduce the cost and complexity of optical transport networks, particularly in the metro aggregation scenario. However, coherent optical receiver is relatively costly and complexity compared with a direct-detection (DD) counterpart due to the use of a synchronized local laser. This paper addresses design issues and performance investigation of intensity modulation/direct-detection (IM/DD) P2MP optical networks. P2MP architectures are designed using digital RF multisubcarrier (MSC) waveform embedded on the intensity of continuous-wave (CW) laser beside direct-detection scheme. The design covers C- and O-band operation using a wavelength-division multiplexing (WDM) architecture. Further single- and double-polarization (SP and DP) versions are reported for each type of the networks. All the architectures are built in Optisystem version 15 environment and simulated for different network parameters, under the assumption of 25 Gbps per subcarrier data rate. The main performance measures are maximum route reach and bit rate-distance product (BDP). The simulation results indicate that DD networks can replaced the coherent counterpart when number of subcarriers per optical channel is 4. Further, the O-band P2MP networks offer high values of maximum reach and BDP than C-band counterparts.
Accurately identifying the kind and amount of dissolved metal salts in wastewater used in oil refining processes is an iconic feature of ultraviolet and visible absorption spectroscopy. This method relies on the dissolved metal salts' ability to absorb light at certain wavelengths after reacting with it. The experiments were conducted in a lab setting with a broadband source (200-800 nm) to measure the absorbance of dissolved element salts and precisely identify the lowest concentration up to 2 ppm. A mixture of the mineral salts from oil refining operations was prepared and diluted to different concentrations using a standard solution. This allowed us to study and compare this result with the absorbance behavior of the wastewater from the Al-Dora Refinery. The two results reinforced that we can accurately estimate the detection parameters for the lowest water contamination. These materials are lead nitrate (PbNO3), phenol, calcium carbonate (CaCO3), sodium chloride (NaCl2), sulfide (SO4), and nitrate (NO3). At wavelengths of 340, 404, and 741 nm, the concentrations (10, 20, 30, 40, 50, 60, 70, 80, 90, and 100) ppm were found, and for the concentration of 10ppm, the absorbance (0.15323, 0.15326, and 0.14685) was found, respectively. The process that has been tested with varying concentrations is considered and simulates the variation in river water concentrations caused by the river's water level and flow rate changes by the effect of rain abundance and thawing. It is fast, accurate data analysis, and a lower cost compared with the other chemical analysis and conventional methods.
In this work, a sensor for cooking oils was designed and fabricated for the first time using hollow-core photonic crystal fiber (HC-PCF). This sensor was studied practically, and the results showed a difference in sensitivity depending on the type of oil. The results showed that the wavelength shift occurred with very small changes in the refractive index of the edible oil. The confinement loss was computed. Seven oils with various refractive indices were utilized. Based on our results, the relative sensitivity to various kinds of Canola oil, Sunflower oil, Olive oil, Walnut oil, Sesame oil, Corn oil, and Wheat oil are 79.9321%, 80.1588%, 77.4523%, 77.4889%, and 77.5650%, 77.6652%, 80.5902% respectively. Moreover, the proposed sensor also has low confinement losses of 6.473×10-9dB/m, 1.158×10-9dB/m, 1.2×10-9dB/m, 1.20×10-9dB/m, 1.199×10-9 dB/m, 1.2×10-9dB/m, and 6.347×10-9dB/m respectively. This sensor can be used to measure the quality of oils and distinguish their types, and they can be a practical element in oil detection systems, which will bring about a change in the future in oil detection methods.
In this work we performed a review regarding the improvement of microscopical optical imaging assisted by using microspheres, focusing on the most recent technologies. We have been reviewed the utilizing of the superlens and nanojet concepts in order to understand the working principles of microspheres in terms of magnification and resolution improvement. Some researches about the parameters effecting on microsphere imaging technique have been presented including the effect of microsphere’s material and size, the effect of immersion medium, and the plasmonic layer effect. Additionally, some applications that serve from this technique have been illustrated.
In recent years, nanoparticles have gained significant attention in the field of cancer treatment due to their extensive potential and wide range of uses. The research mostly focuses on the inorganic chemicals, with a specific emphasis on metals, in order to enhance the comprehension of functional nanoparticles synthesis. This undertaking is motivated by the distinctive characteristics exhibited by these materials, which provide significant advantages for both fundamental scientific inquiry and practical implementations, notably those focused on cancer. The objective of this review is to conduct a comprehensive analysis of the diverse applications of nanocomposites, with a specific focus on their utilization in medication delivery.
The effect of metal nanoparticles (MNPs) on the electric field strength and distribution for improvement solar cell performance is investigated and simulated. By manipulating the properties of nanoparticles, distribution of the electric field was altered. In this paper, classical solar cell (p-n junction) and improved structure (add an extra layer of SiO2 and gold nanoparticles on the top of p-n junction) is simulated. Different sizes of NPs, thickness of SiO2 sublayer, and spacing distance between NPs is done to improving the electric field and showing plamonic effect. Gold NPs deposition on single crystalline silicon solar cell is modelled by COMSOL 5.2 2D, Electromagnetic wave propagation in the frequency domain with periodic boundary conditions. The best wavelength found in our work is 550 nm. The electric field enhances when the size of NPs increases but it must be limited. When gold NPs are deposited on the SiO2 sublayer, the plasmonic effect appears due to decreasing the refractive index. Moreover, separation distance between NPs affect the electric field enhancement by manipulating the number of NPs, the distance decreases and the plasmonic interaction appears.
The aim of this work is to use Fiber Bragg Grating (FBG) to detect the breast cancer at its earliest stages based on the Photoacoustic (PA) hybrid technique. The fiber Bragg gratings sensitivity to acoustic wave, effect of grating length, effect of grating refractive index modification, and ultrasonic frequency on the wavelength sensitivity and intensity sensitivity of the ultrasonic sensor (FBG) for ultrasonic waves were investigated using a simulation programs. A wavelength for the photoacoustic (PA) excitation laser was chosen with respect to a high absorption by the tumor and with low absorption to the surrounding tissue (normal tissue); for higher contrast absorption between them. Fiber Bragg can be used as a sensor to detect the acoustic wave emitted from the tumor (depending on the photoacoustic principle). In this study, k-wave a MATLAB toolbox was used to simulate photoacoustic wave which is detected with fiber Bragg grating simulation, using Optisystem program. The acoustic wave was transferred to FBG by using Optisystem-MTLAB communication programs to detect tumors.
Recently, there is increasing interest in using the 18 THz bandwidth offered by S+C+L band to increase the transmission capacity of fiber communication systems. This leads to the generation of ultra-wideband (UWB) wavelength-division multiplexing (WDM) optical communication systems. In these advanced systems, stimulated Raman scattering (SRS) causes a power transfer from high-frequency channels to low-frequency channels. This effect leads to an increase in the nonlinear interference (NLI) between the UWB-WDM channels. Power optimization techniques are required to balance transfer power between band channels, thus increasing the maximum transmission reach (MTR) along with increasing system capacity. In this paper, the transmission performance of S+C+L band system operating with dual-polarization 16-QAM signaling is investigated using enhanced Gaussian noise model. The transmitter and receiver for each DP channel use a -polarized laser and incorporate two identical configurations, one for x- and the other for y-state of polarization (SOP). The results are presented for two values of symbol rate, 40 and 80 GBaud, where the system carries 360 (=160+80+120) and 180 (=80+40+60) channels, respectively. The results revel that the MTR of both cases is equal to 12 100 km-spans when the channel lunch power equals to -4 and -2 dBm, respectively. This work also shows the effect of NLI components as a function of the number of spans, channel spacing, and channel launch power. The results show that the cross-phase modulation component of the NLI has high accumulated value with transmission distance, while the self-phase modulation component is almost constant.
Orthoses and prostheses were Chosen and laminated based on their high Yield, ultimate stresses, bending stresses, and fatigue limit. Response Surface Methodology (RSM) was utilized to find the best values for two parameters reinforcement perlon fiber and percent of Titanium Nanoparticle coupled with the matrix resin during optimization. The response surface methodology combined the expertise of mathematicians and statisticians to construct and analyze experimental models. Using this method, we identified 13 different lamination samples comprising a wide range of perlon number and Ti nano Wt% in their Perlon layer composition. All lamination materials defined by RSM methods and produced by a vacuum system were subjected to a battery of tests, with fatigue tests performed on the ideal laminating material in contrast to laminations created in the first study (Tensile test, Bending test, and Fatigue tests according to the ASTM D638 and D790 respectively). In comparison to the other 12 laminations tested using Design Expert version 10.0.2, the lamination with ten perlon layers and 0.75 percent Ti nano proved to be the strongest overall in terms of Yield, ultimate, and bending loads. This study used composite materials and titanium nanoparticles to characterize and fabricate ankle foot orthoses. Strength in bending should amount to about 70 MPa, around 85 MPa in tensile tension. Two empirical quadratic equations for the models of peak bending strength and maximum tensile stress with 95% confidence were created using the response surface approach and analysis of variance within the design of experiments software.
In Urban cities, services are supported by intelligent applications and are connected to each other through ad hoc networks. Any service can be operated using a compatible of an Internet of Things (IoT) technology. This study focuses on the transportation service and finding a non-cost solution to solve the crossroads congestion that affected people time and money. The Wireless Sensor Networks (WSNs) that are planted on the roads can help in monitoring the roads situation by collecting their data and send them through wireless communication to a traffic management center. In this work two phases of time are considered for a crowded area. Low-cost components are suggested to solve the congestion at the cross roads without the need for reconstruct the roads. IoT device such as smart phone can be wirelessly connected to the Traffic Management Center (TMC), which can analyze the incoming data from WSN and send back the calculated time to the police officer to control the green light long and overcome the standard time installed for all directions. The main idea is to solve the congestion problem in real time by extending the time long of the green traffic light for the road direction with the highest vehicle density. The suggested algorithm was operated on a dataset of 6 days and for the time phase from 7:00-10:00am.