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The concept of a single frequency band, single high-refractive-index metamaterial has been extended and applied in the design of dual frequency band, dual high-refractive-index metamaterials in the THz regime. The structure design consists of twenty five unit cells with a surface area of 250 um by 250 um and a thickness of 5 um. Each cell has metallic structures embedded in a polyimide substrate. The return loss (S-parameter) analysis shows two strong electric responses at two frequency ranges, and the extracted constitutive parameters suggested high values of simultaneous dielectric constant and permeability at these frequencies. Results retrieved from the S-parameters also show high refractive index values. A first peak refractive index of 61.83 was observed at a resonant frequency of 0.384 THz, and another peak refractive index of 19.2 was observed at the resonant frequency 1.416 THz. Analysis show that higher refractive index at the second resonance frequency band is achievable through redesign of the structures, and modifications could lead to a single structure with multiple frequency, multiple high-refractive-index metamaterials that can be put to practical use.

Soybean seeds codenamed Magellan that can be used as future resources of biofuels were separated into five groups and exposed with electromagnetic fields inside the test chamber with different intensity levels of power, frequency, and time. Seeds after exposure treatments were germinated according to the procedures established by the American Association of Seed Analysts. A hundred seeds from each group were germinated according to these procedures and the percent germination was recorded. Another ten seeds from each treatment, including controls, were manually crushed and placed in separate test tubes for fatty acid analyses. The processed results from the greenhouse confirm effects of electromagnetic fields on the soybean germination. In addition, it is possible that soybean lines with different genetic backgrounds may respond differently to electromagnetic fields in terms of percent seed germination.

A Helmholtz coil was designed and characterized to study the effects of magnetic fields on the germination rate of soybeans. The coil provides a uniform field in a large area such that all the seeds are equally exposed to radiation. An in-house computer code was developed to study the field intensity, specifically the cross-sectional area of uniform field. Experimental results indicate that soybeans grown under static low intensity and super low frequency magnetic fields show improved growth and germination rates when compared to those in the control group. Soybean has potential applications as a renewable energy source for biofuels.

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