Natural Dyes from Ornamental Plants as Sensitizers for Dye-Sensitized Solar Cells (DSSCs): A Review on the Structure-Activity Relationships (SARs) between Power Conversion Efficiencies and Chemical Constituents

Russian Journal of Applied Chemistry - Among the various types of solar cells, the dye-sensitized solar cells (DSSCs) are a type of thin-film solar photovoltaic cells that have been the subject of...     

A Neural Network-Based Optimization Of Thermal Performance Of Phase Change Material-Based Finned Heat Sinks—An Experimental Study

Experiments are conducted to determine the time to reach a set-point temperature for aluminum finned heat sinks filled with the phase change material n-eicosane. Results thus obtained are integrated with a feed-forward back-propagation artificial neural network to predict operating times. The artificial neural network prediction is then used to determine the optimum configuration that maximizes thermal performance. Four different plate-fin heat sink geometries filled with phase change materials giving rise to different volume fractions of the aluminum were experimentally investigated.     

Novel Two-Step Approach for the Synthesis of Cadmium Selenide/Zinc Sulfide Core/Shell Nanocomposites with Precursor Injection Technique

This work describes the synthesis of cadmium selenide/zinc sulfide core/shell nanoparticles from the cadmium oxide precursor through a convenient, two-step approach. This modified novel synthesis procedure for cadmium selenide/zinc sulfide nanoparticles in trioctylphosphine oxide and trioctyl phosphine provides better control over growth dynamics. The outer zinc sulfide shell provides efficient confinement of electron and hole wave functions inside the nanocrystals as well as high photochemical stability. The materials have been characterized using a range of optical and structural techniques. The high resolution transmission electron microscope micrographs of the cadmium selenide/zinc sulfide core/shell nanoparticles show well-defined spherical particles with an increase in diameter as compared to the parent cadmium selenide material. Thus, the present simulation and its extension can give insight to the understanding of the formation of core/shell or other heterostructures in different kinds of self-assembled aggregates.     

Improved Design of 8-Channel Silicon-on-Insulator (SOI) Arrayed Waveguide Grating (AWG) Multiplexer Using Tapered Entry into the Slab Waveguides

An improved design of silicon-on-insulator based 8 × 8 AWG multiplexer is presented using tapered entry into the slab waveguide. Our simulation result clearly shows significant enhancement of electric field from 0.44 V/m to 0.732 V/m, reduction in insertion loss from 7.13 db to 2.7 db, with bandwidth of 230 GHz and channel spacing 200 GHz while keeping other parameters within acceptable limits.     

Potential of Thermo and Alkali Stable Xylanases from Thielaviopsis basicola (MTCC-1467) in Biobleaching of Wood Kraft Pulp

Thermo- and alkali-stable xylanases produced from Thielaviopsis basicola (MTCC-1467) on low-cost carbon source like rice straw were evaluated for their potential application in biobleaching of wood kraft pulp. Enzyme treatment at retention time of 240?min with 20?IU/gm of dried pulp resulted in ~85.2?% of reduction in kappa number. When compared to control, 110.8, 93, and 72.2?% of enhancement in brightness (percent International Organization of Standardization), whiteness, and fluorescence, respectively, were observed for enzyme-treated pulp. Spectroscopic analysis showed significant release of chromophoric compounds from enzyme-treated pulp. Furthermore, scanning electron microscope studies of unbleached and enzyme bleached pulp revealed the effectiveness of enzymatic treatment. The enzyme-treated pulp subjected to later stages of chemical bleaching resulted in 16?% decrease in chlorine consumption along with considerable reduction in chemical oxygen demand percentage (14.5?%) level of effluent. Various pulp properties like fiber length, fiber width, burst strength, burst index, tear strength, tear index, tensile strength, and breaking length were also significantly improved after enzyme treatment when compared to control.     

Measurement of the ground state 2n pickup probability for 28Si+68Zn and its role in sub-barrier fusion enhancement

The ground state and excited state transfer yields for the 2-neutron pickup channel in the ²⁸Si+⁶⁸Zn system have been measured explicitly. The recoil mass separator at the nuclear Science Centre, New Delhi was used for the measurement. A NaI(T1) detector was used for detecting the deexcitation γ’s from the transfer products. The kinematic coincidence technique was employed for the transfer measurement. Simplified coupled channels calculations show that out of all transfer channels the major contribution to the sub-barrier enhancement comes from the ground state 2 neutron pickup channel with a ground state Q-value of+1.83 MeV.     

Some considerations on the design of a high-power N2 laser

The design of a high-power transverse discharge N₂ laser is reported. TThe overall maximum efficiency of the laser is 0.51%— thought to be the second highest value reported so far. Details of the pressurized and free-running type spark gap switch and certain parametric studies are also given.     

Fluctuations in SU(2) Yang-Mills theory

The nonlinear differential equation resulting from the use of the ’t Hooft-Corrigan-Fairlie-Wilczek ansatz in SU(2) Yang-Mills gauge theory is solved by the bilinear operator method. The solutions which are singular are interpreted as fluctuations involving no flux transport. However, these objects may play a tunnelling role similar to that of merons.