Analysis of the Scattering of Surface Plasmon Polariton Waves from a Perfectly Conducting Circular Cylinder

Surface plasmon polariton (SPP) waves are the most extensively studied waves among various types of surface waves because they are easy to excite and have been used in many optical applications particularly for plasmonic communication, sensing, and harvesting solar energy. In all these applications, especially on-chip plasmonic communication, scattering can be an important issue to deal with. Therefore, this paper aimed to theoretically inspect the scattering pattern of SPP waves from a perfect electric conductor (PEC) cylindrical scatterer. The cylindrical wave approach is used to solve the scattering problem by a cylindrical object placed below a metallic layer. The scattering is investigated thoroughly by changing the size of the scatterer and its distance from the interface along which the SPP wave is excited. As the size of the scatterer increases, the scattering increases significantly. On the other hand, when the distance of the scatterer from the interface is increased, the scattered field becomes small. Two-dimensional field maps are produced for the incident angle at which SPP is excited. Numerical results are also presented for other incident angles to make a comparison. Furthermore, the forward and backward far-fields are significantly enhanced if the SPP wave is scattered in comparison with when the SPP wave is not present.

     

Use FMEA method for environmental risk assessment in ore complex on wildlife habitats

Human activities are the most effective cause of wildlife habitat destruction and loss of quality. Some of these activities are the construction, operation, and utilization of mines. The present study investigates factory activity in the GolGoharSirjanOre Complex (Kerman province) and environmental risk assessment of the activities done by this complex on wildlife habitat. In order to identify the significant aspects of the complex, the Failure Mode and Effects Analysis (FMEA) method is used. To determine the risk priority number, the significant aspects resulted from the multiplication of the criteria including probability of occurrence, the probability of detection, and severity of the effect. Based on the results of the current study, most of the activities of GolGoharSirjan Complex can have a significant adverse impact on the habitat of birds such as bustard Chlamydotisundulata (Vulnerable [VU]) and Podocespleskei, and mammals such as Striped Hyaena (Hyaenahyaena) (Near Threatened [NT]) and Capra aegagrus (Wild Goat) (VU). Some of the most important activities related to the activity include: Crusher (Risk Priority Number [RPN] = 720), the concentration of iron ore (RPN = 640), mining (RPN = 486), Stalker and Reclaiming (RPN = 504), and the transport of heavy machinery (RPN = 432). Significant aspects such as the emission of dust into the air; Nitrogen Oxide (NOX), Sulphur Oxide (SOX), and Hydrogen Sulfide (H2S) gas emissions to air; vibration; noise; and industrial waste discharges significantly influence the environment. The results of measurements of environmental pollutants that are carried out by reliable environmental laboratories have shown that the amount of pollutants mentioned are above the standard limit determined by the Iranian Department of Environment.     

Plasmonic Sensor Using a Combination of Grating and Prism Couplings

Plasmonics - Surface plasmon-polariton (SPP) waves guided by an interface of a metal and a dielectric material with a combination of grating- and prism-coupled configurations are theoretically...     

Alternanthera bettzickiana (Regel) G. Nicholson,a potential halophytic ornamental plant: Growth and physiological adaptations

Exploration and cultivation of salt tolerant plants is a very effective strategy for utilization of salt affected soils. In this investigation, physiological traits that are conducive for salt tolerance of the ornamental plant Alternanthera bettzickiana, Amaranthaceae, were explored. A. bettzickiana was grown on soil substrate having six salinity levels (2.86, 10, 20, 30, 40 and 50 dS m⁻¹). It was observed that this plant can grow even at a salinity level of 40 dS m⁻¹. The survival rate of this plant was 75, 42 and 0% at salinity levels of 30, 40 and 50 dS m⁻¹, respectively. A. bettzickiana plants produced 30.3% less biomass than controls at the salinity level of 20 dS m⁻¹ and even less under still higher salt stress. Photosynthesis continued even at the salinity level of 40 dS m⁻¹, though its rate was reduced to 59% in plants exposed to such salinity relative to plants not affected by salinity. Total soluble proteins values in leaf and stem showed a gradual increase when plants were exposed to increasing salt stress. Plants growing at the high salinity level showed highest decrease in leaf nitrate reductase activity. A. bettzickiana plants accumulated less Na⁺ in shoot as compared to root when grown under salt stress. It can be characterized as a salt-tolerant glycophyte that could be used for greening of salt affected soils.     

Enhancement of Dynamic Sensitivity of Multiple Surface-plasmonic-polaritonic Sensor Using Silver Nanoparticles

Multiple surface plasmon-polariton (SPP) waves excited at the interface of a homogeneous isotropic metal and a chiral sculptured thin film (STF) impregnated with silver nanoparticles were theoretically assessed for the multiple-SPP-waves-based sensing of a fluid uniformly infiltrating the chiral STF. The Bruggemann homogenization formalism was used in two different modalities to determine the three principal relative permittivity scalars of the silver-nanoparticle-impregnated chiral STF infiltrated uniformly by the fluid. The dynamic sensitivity increased when silver nanoparticles were present, provided their volume fraction did not exceed about 1 %.     

Nemato-toxic analysis of several chopped plant leaves against Meloidogyne incognita affecting tomato In vitro and In pots

Tomato plant is affected by several pathogens, including root-knot nematodes (RKNs), belonging to the genus Meloidogyne. Meloidogyne incognita is among the most potent pests infecting tomato roots. Therefore, it is of interest to discuss the management of Meloidogyne incognita using selected botanicals such as Cammelina benghalensis, Evolvulus nummularius, Gomphrena celosioides, Lindenbergia indica, Scoparia dulcis and Vernonia cinerea. The second-stage juveniles (J2s) of M. incognita were directly treated with the aqueous extracts of the botanicals at varied concentration ranging from 10-100%. 100% concentration of Lindenbergia indica was found to be the most toxic against the survival of J2s of M. incognita as compared to other concentrations. In vitro tests also showed the maximum inhibition in egg hatching at 100% concentration after seven days in the extract of Lindenbergia indica. Moreover, botanicals significantly reduced the infestations in relation to number of root galls, eggmasses/root and nematode population/250 g soil in pots. The plant treated with Scoparia dulcis leaves showed the highest nematicidal efficacy with maximum reductions in all the pathological parameters as compared to the untreated control. All treatments resulted in increased growth, physiological parameters and decreased pathological parameters of tomato.     

On Surface-Plasmon-Polariton Waves Excited in the Turbadar–Otto Configuration

Plasmonics - A local minimum in the plot of linear reflectance versus angle of incidence, on its own, is insufficient to identify a surface-plasmon-polariton wave (SPPW). Further checks are...