Search

For a reliable and risk-free power source, dye-sensitized solar cells (DSSCs) have been the subject of much research. The method is very attractive because of its cheap manufacturing cost, environmentally friendly manufacture, and competitive efficiency. This study constructed a heterojunction as a photoanode for DSSCs using a combination of TiO2 and graphene using a wet chemical technique. According to the XRD and TEM findings, the graphene sheets consist of evenly wrapped spherical nanoparticles with diameters ranging from 30 to 40 nm, and the TiO2 exhibits a tetragonal (anatase) phase. It is common for anatase to have a bandgap energy of 3.15 eV for TiO2, whereas graphene/TiO2 has a bandgap energy of 2.77 eV. With a power conversion efficiency (PCE) of 7.2%, graphene/TiO2 DSSCs outperform cells based on pure TiO2 electrodes by a margin of 2.22%. In particular, graphene's ability to absorb solar light has the potential to improve the power conversion efficiency of DSSCs by increasing the light harvest of dye molecules. In addition, graphene/TiO2 had an average electron transit time of 1.765 ms while TiO2 had an average of 2.981 ms. The research shows that DSSCs' power conversion efficiency may be greatly improved by strategically adding graphene, which can be affordably synthesized, to certain layers of the photoanode. [ABSTRACT FROM AUTHOR]

High-quality single crystals of magnesium zinc hydrogen phosphate (MgZnHPO4) with diameters of up to 8 × 2 × 2 mm3 have been successfully grown using sodium meta silicate gelatin. The crystal’s classification has been confirmed as orthorhombic, belonging to the Pnma space group, using single crystal X-ray diffraction investigations. Moreover, the calculated lattice parameters and volume were a = 10.491 Å, b = 18.152 Å, c = 5.043 Å, Z = 4, respectively. Fourier transform infrared results suggest that the intense peak observed at 1110 cm−1 is ascribed to the stretches mode of the P–O bond and the planar bent shape of the (PO4)3− ion. Scanning electron microscope images show that both the crystals having needle shaped platelets like surface morphology. The energy absorption gap is a straight band gap with a magnitude of 3.72 eV. The crystal’s high band gap clearly indicates its exceptional transparency. The crystal’s activation energy had been determined to be 0.34 eV at a frequency of 1 kHz. Moreover, the AC conductivity and photocurrent measurement was carried out for grown crystal. The second harmonic generation (SHG) efficiency of MgZnHPO4 was determined to be 28.9 millivolts (mV), which is 2.7 times higher than that of a potassium dihydrogen phosphate (KDP) single crystal (10.71 mV). It is very clear that this crystal has potential and prospects for frequency conversion applications. [ABSTRACT FROM AUTHOR]

Multimedia technology usages is increasing day by day and to provide authorized data and protecting the secret information from unauthorized use is highly difficult and involves a complex process. By using the watermarking technique, only authorized user can use the data. Digital watermarking is a widely used technology for the protection of digital data. Digital watermarking deals with the embedding of secret data into actual information. Digital watermarking techniques are classified into three major categories, and they were based on domain, type of document (text, image, music or video) and human perception. Performance of the watermarked images is analysed using Peak signal to noise ratio, mean square error and bit error rate. Watermarking of images has been researched profoundly for its specialized and modern achievability in all media applications such as copyrights protection, medical reports (MRI scan and X-ray), annotation and privacy control. This paper reviews the watermarking technique and its merits and demerits. [ABSTRACT FROM AUTHOR]

We propose a low power and area efficient two-cycle multiply-accumulate (2C-MAC) architecture which supports 2's complement numbers, and includes accumulation guard bits and saturation circuitry. The first MAC pipeline stage contains only partial-product circuitry which is for generating partial product. And the second stage consists of sign-extension block, saturation unit and all other functionality. Proposed architecture does not need any additional cycles to generate the final result. It efficiently produces the addition of the accumulated value and the product in each cycle. And extend the new architecture to create a double throughput MAC, which can perform either multiply or multiply-accumulate operations. [ABSTRACT FROM AUTHOR]