Research Prospects in Natural Sciences (RPNS)

Electromagnetic wave propagation in a rectangular waveguide filled with a double-negative (DNG) metamaterial

Burhan Zamir, Zeeshan Naseer, Babar Shahzad — Wed, 26 Jun 2024 00:00:00 +0000

This article presents an analysis of electromagnetic wave propagation in a model of rectangular waveguide when filled with a double-negative metamaterial. The field components and dispersion relation of the electromagnetic waves are calculated, analytically. The dispersion relation is numerically analysed by plotting the normalized squared phase velocity against the propagation frequency for the variation of the parameters of the waveguide and the wave. The dominant mode is found to be TE¹⁰ mode. The dispersion curves show propagation and non-propagation characteristics for larger dimensions and for dominant mode. Some aspects were found to be much different from a conventional rectangular waveguide.

Island Size Distribution Study for Rubrene Thin Films on Muscovite Mica and SiO2 Using Scaling Theory

Kamila Rehman, Aaliya Rehman, Shaimaa M. Abdalbaqi, Helmut Sitter — Wed, 26 Jun 2024 00:00:00 +0000

For the application of various theories to find a growth model for rubrene, it is essential to analyze the nucleation process during initial stages of growth. Here we present a study of rubrene deposited by Hot Wall Epitaxy on mica and SiO₂ using different substrate temperatures and calculating the island size distribution for each temperature. In order to find a growth model for rubrene we apply scaling theory during these initial stages of growth.

A new steroid from chloroform extract of Tamarix indica

Sumra Amanat — Wed, 26 Jun 2024 00:00:00 +0000

A new steroid compound along with four known compounds were first time purified from the chloroform soluble fraction of the Tamarix indica. The structures of the isolated compounds were characterized on the basis of modern sophisticated, EIMS, HREIMS, 1D and 2D NMR spectroscopic techniques. The known compounds were recognized as Lupeol (2) Stigmasterol (3) , Ursolic acid (4), Oleanolic acid (5) and computational analysis of new compounds were also done.

Methanolic Extracts of Grapefruit (Citrus paradesi) Peel, Pulp and Seed and their Antioxidant Activity

Zafar Iqbal, Abeera Zafar — Wed, 26 Jun 2024 00:00:00 +0000

Fresh grapefruits (Citrus paradesi) were collected from the vegetable market of Lahore Division, Punjab Pakistan. Their peel, pulp, and seed were subjected to drying and grinding which was followed by extraction with methanol. These methanolic extracts were further investigated to check their antioxidant activities by using 2,2-diphenyl-1-picryl-hydrazyl (DPPH). The antioxidant activities showed that the grapefruit peel methanolic extract with concentrations of 25µL, 50µL, 75µL, and 100µL has DPPH inhibition 73.6%, 76.4%, 78.8%, and 82.7% respectively. While the grapefruit pulp methanolic extract having concentrations 25µL, 50µL, 75µL, and 100µL has DPPH inhibition 60.3%, 67.3%, 73.6%, and 78.9% respectively and the grapefruit seed methanolic extract with concentrations 25µL, 50µL, 75µL, and 100µL has DPPH inhibition59.1%, 65.7%, 71.5%, and 75.9% respectively. The results of these extracts were concentration-dependent.

Evaluation and Extraction of Natural Hair colors from different Herbal and Dry Fruit Items for Formulation.

Wed, 26 Jun 2024 00:00:00 +0000

In the present investigation, attempts were made to make a powder herbal hair dye resembling natural hair color with better dyeing effect, superior quality, long-lasting, and hundred percent pure. Synthetic hair dye includes dye modifiers, antioxidant alkalizers, soap ammonia, wetting agents, fragrances, and a variety of other softening agents that are harmful to health and cause cancer. To overcome these problems in the present investigation, we developed a method to get a natural brown color using a combination of different plant materials, i.e., amla (Emblica officinalis gaertin), olive (Olea europaea), almond peel, and peanut peels. The current study examined several combinations of hair-care plants, including henna, peanut, almond, walnut, indigo, and aloe vera. Additionally, basic and inexpensive ingredients were used, saving money and foreign exchange. We get brown hair naturally from these raw materials, which are themselves medicines for hair growth and have an endless list of therapeutic benefits that antimicrobial, antiseptic, and anti-inflammatory herbs impart. Brown color and a scalp free from dandruff ensure quality with no side effects. It is a pharmacologic invention for ageing hair, which is a vital alteration for synthetic hair dye. It is a 100% natural source. A natural herbal hair dye is an excellent colorant for all types of hair because synthetic dyes have the chief disadvantage of causing preventive reactions and hair loss. All natural hair dyes are made from plants using the latest scientific achievements in green chemistry. The result obtained from the brown hair dye process investigation confirmed that hair dye prepared from hulls was excellent and economical, with a number of benefits for hair.