Papers by Keyword: Light Intensity

Abstract: Silver nanowires (AgNWs) have garnered significant attention for their applications in flexible electronics, sensors, and transparent conductive films. Traditional synthesis methods are often energy-intensive and involve hazardous chemicals. However, this study investigated a green synthesis approach using tannic acid as reducing and stabilizing agents, focusing on the effect of light intensity on nanoparticle formation. AgNWs were successfully synthesized at room temperature via a light-assisted reduction method using tannic acid. Various intensities of blue light with a wavelength of 456-467 nm were applied to determine their influence on the morphology AgNWs. Light intensity was found to play a crucial role in controlling the nucleation and growth rate of AgNWs. Higher intensities accelerated the reduction of Ag⁺ (silver ion) to Ag⁰ (silver atom), promoting the formation of longer nanowires with increased diameters. Furthermore, these AgNWs demonstrated good stability after one month of storage, with zeta potential values of-20.0 ± 1.01 mV. This study demonstrated that blue light intensity significantly affected the morphology of AgNWs synthesized using tannic acid, providing a sustainable and tunable method for fabricating high-aspect-ratio nanowires under mild conditions.

Abstract: A wide range of Light Emitting Diodes (LEDs) applications, from general lighting to transmission sources of the Visual Light Communication (VLC) system, makes the LEDs very important to be developed. This research focuses on comparing LED performance due to the variation in surface size and shape of the LED. The research method is carried out with a simulation and an experimental approach. Before the experiment, the LED was simulated with nanopattern variations to determine the best fabrication parameter. The simulation method is carried out using Ansys Lumerical FDTD 2021. The experiment method used to fabricate nanopatterns on the surface of a semiconductor LED layer uses the nanoimprint lithography method. Stamps for nanoimprint lithography are made using Polydimethylsiloxane (PDMS), and the nanopattern sources are obtained from DVD and Blu-ray grating patterns. The characterization of nanoscale patterns was carried out using a Scanning Electron Microscope (SEM). The light emission intensity is measured using a lux meter at a series of emission angles. The results obtained from this research are that the smaller the width and the periodicity of the grating nanopattern, the light produced will be distributed at a wider angle, but the light intensity will decrease; conversely, for a planar surface without a grating nanopattern, level of focus and intensity of light will be higher. In addition, the thicker the ZnS:Cu layer, the better the intensity of the light produced.

Abstract: We have grown a SrTiO₃ thin film from strontium acetate and titanium isopropoxide using chemical solution deposition (CSD) method using a spin coater, and furnace annealed with a temperature of 850°C for 8 hours. We have assessed the thin-film frequency, magnetic field, and electric charges using LCR meter and light intensities of 0 (dark), 4000, 8000, 12000 lux. From the data of LCR meter, it can be measured and see the relationship between the current and the angular velocity will be decreased. Also, the results of the measurements obtained the relationship between magnetic fields and angular velocity is reduced as well. Therefore, we can be assumed the higher the intensity of light shall lower the magnetic properties.

Abstract: The influence of light irradiation with different intensity parameters and different spectral composition on morphogenic structures, namely green zones of cultivar Dolinny cell cultures was investigated. Light irradiation was generated by 10 types of LEDs with different spectra: cold white (Cold W), white (W), warm white (Warm W), Full spectrum, Red, Deep Red, Yellow, Green, Blue and Royal Blue. It was shown that LEDs with Cold W, W and Royal Blue more actively influenced on green zones generation, while Red, Red Deep, Yellow и Green displayed no results. Standard fluorescent lighting illumination (WFL) was used as a control. The number of induced green zones was lower under control luminescent light (WFL) in comparison with the green zones, which were induced by the illumination of the most active spectra of LEDs, but lifetime of these control structures was longer. After 19 weeks of cultivation, degradation of the green zones of the calli was not observed under control and LEDs Cold W, Warm W, and Blue in the position with maximal intensity of light. The Royal Blue illumination displayed the same results not only in the position with maximum intensity but also at the other intensities approaching the control values (49,3 230 μmol/s*m2).

Abstract: The innovative LED light source (Sun Box) with irradiation spectrum close to the sun spectrum in the wavelength range 440-660 nm was used in experiment for study the influence of light intensity (75, 135, 230 and 382 μmol/s*m²) on the growth and development of plants. Standard fluorescent lighting was used as a control. The experiments were carried out on plantlets of Stevia rebaudiana and Solanum tuberosum, cvs. Snegir, Rozhdestvenskiy and Kamchatskii) in vitro. The illumination intensity of 75 and 230 μmol/s*m² promoted development of S. rebaudiana plantlets with optimal values of morphometric parameters and well developed roots, which is important for plantlet adaptation to soil conditions. For S. tuberosum plantlets (Snegir and Rozhdestvenskiy cultivars), radiation intensity of 135 μmol/s*m² was optimal for micropropagation. The illumination intensity of 230 μmol/s*m² led to a formation of plantlets with the largest total fresh mass among experimental groups. Sun Box light with intensity of 75 μmol/s*m² could be applicated for micropropagation of these cultivars: plantlets were the highest with the largest internodes number. Thus, the plant response to different light intensity was species-spesific, and – in case of potato plantlets – cultivar-spesific. The use of artificial light sources with distinct PPFD level could be preferable for S. tuberosum and S. rebaudiana plantlet micropropagation in vitro, as it could shorten the cultivation time, accelerate cultivation time, and reduce the cost of electricity.

Abstract: This work is devoted to investigation of the way light transmittance of drying drop of Fe₂O₃ nanocolloid deposited on flat surface changes as liquid evaporates. According to results of transmitted light intensity measuring it is assumed that drying process can be divided into separate stages each being characterized by particular quality level of ability to transmit light because of different behavior and, thus, density of suspended nanoparticles inside the droplet. The last stage ends by forming of a ring-shaped pattern (known as “coffee ring”). Temperature of the surface was being changed by applying a varying potential difference to lower layer of transparent substrate made of ITO. Time dependences of integral transmitted light intensity for every single temperature are represented in graphs. They are compared with dependences for water drops of the same volume.

Abstract: Effects of solar panels must be taken into account by the light intensity of its output characteristics in practical application, especially solar panels placed outdoor. So the light intensity coefficient is an important parameter to be considered. In this paper,we took the light intensity characteristics of single crystal silicon solar cell as the research object. Also,through transforming the illumination intensity which are 777.60W/m²,996.97 W/m² and 1224.88 W/m², we would finish researching the characteristics of the cell sheet, which included battery plate volt ampere characteristic, open circuit voltage, short circuit current and maximum output power. Also, we’ve got the relationship of U_oc-T, I_sc-T and P_m-T, respectively and Put forward the better intensity theory. It would lay a solid foundation of practice for the further study on how to improve the rate of light conversion.

Abstract: Post hydrothermal liquefaction wastewater (PHWW) was generated during biocrude oil production. It contains lots of carbon, nitrogen and phosphorous elements, which can cause environmental pollution and resource waste. Using photosynthetic bacteria (PSB) to treat this kind of wastewater can realize pollutants elimination and resource recovery. In this work, the feasibility of using PSB to treat PHWW was firstly investigated, and the treatment conditions were optimized. Results showed that the PSB can effectively degrade PHWW. The optimal initial COD concentration, inoculum size and light intensity for PSB to treat PHWW were 6000-10000 mg/L, 50 mg/L and 1000-3500 lux, respectively. With the initial COD concentration of 9000 mg/L, inoculum size of 50 mg/L and light intensity of 1000 lux, the COD, NH₃-N, TP removal and biomass production reached to 71%, 90%, 47.2% and 773 mg/L, respectively. This showed that using PSB to treat PHWW can be an alternative method for PHWW nutrients recovery and pollutant treatment.

Abstract: This paper designed the wind-solar hybrid electricity generation system, it might offer users reliable power supply when the climate and other factors change. The system has a variety of operation modes, can be either manually or automatically transforms. Each mode can be selected manually switching storage batteries to achieve the reliable power supply and prolong the battery service life. Through Matlab simulation analysis, the feasibility of the control system has been verified. Simulation results show that the system output stability, it can satisfy user demand.

Abstract: Computational photography and image processing technology are used to restore the clearness of images taken in fog scenes autmatically.The technology is used to restore the clearness of the fog scene,which includes digital image processing and the physical model of atmospheric scattering.An algorithm is designed to restore the clearness of the fog scene under the assumption of the albedo images and then the resolution algorithm is analysised.The algorithm is implemented by the software of image process ,which can improve the efficiency of the algorithm and interface.The fog image and defogging image are compared, and the results show that the visibility of the image is improved, and the image restoration is more clearly.