Solar Energy Conversion and Storage: Rose Bengal-Triton X-100 by Photogalvanic Cell

Photogalvanic cells are photoelectrochemical devices involving ions as mobile charges moving in solution through diffusion process. These cells are capable of solar power generation at low cost with inherent storage capacity. This property of photogalvanic cell needs to be exploited as this technology is cleaner and promising for application in daily life. In our work, Rose Bengal is used as photosensitizer with oxalic acid as reductant and triton as surfactant for photoelectrochemical conversion of solar energy into electrical energy. The photopotential and photocurrent generated were 289.0 mV and 29.1 µA, respectively. The maximum power of the cell was 8.409 µW. The observed conversion efficiency was 0.023 % and fill factor was determined as 0.293 against the maximum theoretical value 1.0. The photogalvanic cell can work for 45.0 min in dark after irradiation for 21.0 min, i.e. the storage capacity of the photogalvanic cell is 45 min. The effect of different parameters on electrical output of the cell was studied and a mechanism has also been proposed for the generation of photocurrent in photogalvanic cell. Keywords: Rose Bengal; Oxalic acid; Triton; Conversion efficiency; Storage capacity; Photocurrent

Deep learning model for thorax diseases detection

Despite the availability of radiology devices in some health care centers, thorax diseases are considered as one of the most common health problems, especially in rural areas. By exploiting the power of the Internet of things and specific platforms to analyze a large volume of medical data, the health of a patient could be improved earlier. In this paper, the proposed model  is based on pre-trained ResNet-50  for diagnosing thorax diseases. Chest x-ray images are cropped to extract the rib cage part from the chest radiographs. ResNet-50 was re-train on Chest x-ray14 dataset where a chest radiograph images are inserted into the model to determine if the person is healthy or not. In the case of an unhealthy patient, the model can classify the disease into one of the fourteen chest diseases. The results show the ability of ResNet-50 in achieving impressive performance in classifying thorax diseases

Synthesis of Mesoporous TiO2 Template-Free and Photocatalytic Activity for Azo Dye Degradation

Nanoporous titanium dioxide was prepared by sol-gel technique. To control the surface area, pore size and pore volume of the prepared TiO2, a catalyzed hydrolysis was carried out using different concentrations of silicotungstic acid (SWA) as a template. A fixed molar ratio of H2O/Ti was used. The prepared TiO2 was calcined at 400 or 600oC. Samples were characterized by nitrogen physic-sorption, X-ray powder diffraction (XRD), selected scattered electron diffraction, Raman spectroscopic analysis, Fourier Transform spectroscopy (FTIR), Thermo gravimetric analysis (TGA), Differential scanning calorimetry (DSC), scanning and transmission electron microscopy (SEM and TEM). The photocatalytic activity of the prepared samples was evaluated by the degradation of alizarin yellow under UV light. The results showed that the crystallinity increases as the concentration of SWA decreases. The presence of SWA during the precipitation of TiO2 prevents the formation of rutile phase and suppresses the crystal growth. The results showed also that the surface area increases as the concentration of SWA decreases. The samples prepared using 0.05M SWA and calcined at 600 oC showed a higher activity. Keywords: mesoporous TiO2, photocatalytic degradation, alizarin yellow, azodye

Sol–Gel and Thermally Evaporated Nanostructured Thin ZnO Films for Photocatalytic Degradation of Trichlorophenol

In the present work, thermal evaporation and sol–gel coating techniques were applied to fabricate nanostructured thin ZnO films. The phase structure and surface morphology of the obtained films were investigated by X-ray diffractometer (XRD) and scanning electron microscope (SEM), respectively. The topography and 2D profile of the thin ZnO films prepared by both techniques were studied by optical profiler. The results revealed that the thermally evaporated thin film has a comparatively smoother surface of hexagonal wurtzite structure with grain size 12 nm and 51 m2/g. On the other hand, sol–gel films exhibited rough surface with a strong preferred orientation of 25 nm grain size and 27 m2/g surface area. Following deposition process, the obtained films were applied for the photodegradation of 2,4,6-trichlorophenol (TCP) in water in presence of UV irradiation. The concentrations of TCP and its intermediates produced in the solution during the photodegradation were determined by high performance liquid chromatography (HPLC) at defined irradiation times. Complete decay of TCP and its intermediates was observed after 60 min when the thermal evaporated photocatalyst was applied. However, by operating sol–gel catalyst, the concentration of intermediates initially increased and then remained constant with irradiation time. Although the degradation of TCP followed first-order kinetic for both catalysts, higher photocatalytic activity was exhibited by the thermally evaporated ZnO thin film in comparison with sol–gel one

Overlapped hierarchical clusters routing protocol for improving quality of service

The rapid development in communications and sensors technologies make wireless sensor networks (WSNs) as essential key in several advanced applications such as internet of things (IoT). The increasing demands on using WSNs required high quality of services (QoS) because most WSNs applications have critical requirements. This work aims to offer a routing protocol to improve the QoS in WSNs, taking in consideration its ability to prolong the lifetime of the network, optimize the utilization of the limited bandwidth available, and decrease the latency that accompanies the packets transmitted to the gateway. The proposed protocol is called overlapped hierarchical cluster routing protocol (OHCRP). OHCRP is compared with the traditional routing protocols such as SPEED, and THVR. The results show that OHCRP reduces latency effectively and achieve high energy conservation, which lead to increase the network lifetime and insure network availability

Preparation and Characterization of Various Interstitial N-Doped TiO2 Catalysts from Different Nitrogen Dopants for the Treatment of Polluted Water

In this work N-doped TiO2 nano particle photocatalysts were prepared through a sol-gel procedure using three different types of nitrogen dopants urea, diethanolamine (DEA) and triethylamine (TEN). Multiple techniques (XRD, TEM, SEM, EDX, BET, Raman and UV-Visible absorption) were commanded to characterize the crystal structure of N-doped TiO2. The catalytic activity of the N-doped TiO2 under ultraviolet (UV) and visible light irradiation is evidenced by the decomposition of 2-chlorophenol, showing that nitrogen atoms in the N-doped TiO2 are responsible for the visible light catalytic activity. It is suggested that doped nitrogen here is located at the interstitial site of TiO2 lattice. Amongst investigated nitrogen precursors diethanolamine provided the highest visible light absorption ability of interstitial N-doped TiO2 with the smallest energy band gap and the smallest anatase crystal size, resulting in the highest efficiency in 2-cholorophenol degradation. The photocatalytic activity and 2-CP mineralization ability of all N-doped TiO2 can be arranged in the following order:  TiO2/DEA > TiO2/TEN > TiO2/UREA > un-doped TiO2. Keywords: 2-chlorophenol, Photocatalytic degradation, N-doped TiO2, Different Nitrogen Dopants, urea, diethanolamine (DEA), triethylamine (TEN) and Catalytic Activity

High efficiency dye-sensitized solar cells with a novel two dimensional Cd-V-LDH photoanode

The present study demonstrates a novel photoanode layer double hydroxide (LDH) for dye-sensitized solar cells (DSSCs). The search for a photoanode (PA) with low cost and high power conversion efficiency (PCE) has become one of the most significant challenges facing researchers. LDH has proven successful as a photocatalyst in various fields. In this paper, a novel Cd-V-LDH with a molar ratio of Cd:V = 1:1 was synthesized by the coprecipitation method and used as a novel PA in DSSCS. X-ray diffraction (XRD), Raman spectroscopy, Scanning electron microscopy (SEM), Fourier Transform infrared spectroscopy (FTIR), Nitrogen sorption analysis, UV–Vis absorption spectrum, Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to examine the produced Cd-V-LDH. Cd-V-LDH as PA, Eosin Y (EY) as a photosensitizer, LiI-I2 as a liquid electrolyte, and g-C3N4 (GN) as a photocathode (PC) are the component of DSSCs. The series cells of DSSCs were assembled and the available variables have been studied to achieve the best performance under normal conditions. These variables, e.g., concentration and pH of EY, active area of PA, and different types of PC, e.g., graphene oxide (GO), commercial carbon (CC), and (GN). The open circuit voltage (VOC) and short circuit current density (JSC) for the Cd-V-LDH/EY/LiI-I2/GN system were observed to be 705 mV and 12.40 mA/cm2, and has a PCE of 5.4% comparable to Cd-V-LDH/EY/LiI-I2/GO and Cd-V-LDH/EY/LiI-I2/CC, which have PCEs of 4.9% and 3.8%, respectively, in the identical testing conditions

Gamma-Irradiation Improves the Photocatalytic Activity of Fe/TiO2 for Photocatalytic Degradation of 2-Chlorophenol

The Fe doped TiO2 abbreviated here as (Fe3) were prepared by sol-gel method. Upon doping FeTiO3 nano-composite was formed. The prepared sample was irradiated by different dosage of γ-irradiated (0.2, 0.4, 0.8 and 1.6 MGy).  The irradiated samples which abbreviated as (0.2, 0.4, 0.8 and 1.6 MGy) and non-irradiated sample which abbreviated as (Fe3)  were characterized by X-Ray Diffraction (XRD), Surface analysis, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Temperature Programmed Desorption (NH3-TPD), Raman Spectroscopy,  and UV-Vis absorption. The results show that γ-irradiation not only improves the morphological and structural changes of irritated samples, but also extended its absorption edge to the visible light region. The photocatalytic activity of the samples were tested for the photocatalytic degradation of   2-chlorophenol under simulated solar light irradiation. The photocatalytic activity of the irradiated sample using 1.6 MGY was higher than the other irradiated and non-irradiated samples. The photo-intermediate product was also studied. Keywords: Photocatalysis, TiO2, 2-chlorophenol, photocatalytic degradation, Gamma-irradiation

Evaluation of the safety and antioxidant activities of Crocus sativus and Propolis ethanolic extracts

AbstractThe possible toxicological effects and in vitro antioxidant activity of the ethanolic extracts of Crocus sativus and Propolis were investigated. Both extracts did not cause any mortalities or signs of toxicity in mice when administered orally at doses up to 5g/kgb.wt. In the sub-chronic study; the tested extracts did not produce any significant change in liver and kidney functions of rats, following oral administration for 8 successive weeks at doses of 500mg/kgb.wt. of each. Propolis showed remarkable in vitro antioxidant activity at concentrations of (40–100mg/ml). In contrast, the ethanolic extract of C. sativus ethanolic extract showed weak antioxidant activity in concentrations of (1–10mg/ml) while at concentrations of (20–100mg/ml) failed to exhibit any antioxidant activity. It was concluded that: both extracts were non-toxic, as they did not cause any mortalities or signs of toxicity in mice when administered orally at doses up to 5g/kgb.wt. Daily oral administration of C. sativus, Propolis ethanolic extracts alone or in combination for 8 successive weeks to rats was quiet safe and didn't cause any toxic changes in liver and kidney. Antioxidant study showed that Propolis ethanolic extract was a more potent antioxidant than C. sativus extract

Spectroscopic investigations of pentobarbital interaction with human serum albumin

The interaction between pentobarbital and human serum albumin has been investigated. The basic binding interaction was studied by UV-absorption and fluorescence spectroscopy. From spectral analysis pentobarbital showed a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The binding constant (k) is estimated at 1.812 104 M 1 at 293 K. FT-IR spectroscopy with Fourier self-deconvolution technique was used to determine the protein secondary structure and drug binding mechanisms. The observed spectral changes of HSA–pentobarbital complex indicate a larger intensity decrease in the absorption band of a-helix relative to that of b-sheets. This variation in intensity is related indirectly to the formation of H-bonding in the complex molecules, which accounts for the different intrinsic propensities of a-helix and b-sheets.This work is supported by the German Research Foundation DFG Grant No. DR228/24-2