AMC Integrated Multilayer Wearable Antenna for Multiband WBAN Applications

In this paper,a compact,efficient and easy to fabricate wearable antenna integrated with Artificial Magnetic Conductor(AMC)is presented.Addition of slots and bevels/cuts in the rectangular monopole patch antenna yield a wide bandwidth along with band notches.The proposed antenna is backed with an AMC metasurface that changes the bidirectional radiation pattern to a unidirectional,thus,considerably reducing the Specific Absorption Ratio(SAR).The demonstrated antenna has a good coverage radiating away from the body and presents reduced radiation towards the body with a front-to-back ratio of 13 dB and maximum gain of 3.54 dB.The proposed design operates over a wide frequency band of 2.9 to 12 GHz(exceeding the designated 3.1−10.6 GHz Ultra-Wideband(UWB)band).The band notches were created using slots on the radiating patch in the sub-bands from 5.50 to 5.67 GHz and 7.16 to 7.74 GHz.The overall dimensions of the structure are 33×33×6.75 mm3.The antenna’s radiation performance increased considerably with the addition of the AMC layer.The SAR values for the antenna are reduced by 85.3%when the AMC is used and are 0.083 W/kg which is well below the FCC SAR limits.The simple design,miniaturized profile,low SAR and wide operating bands with multiple band notches make the presented antenna an appealing choice for several UWB wearable body area network(WBAN)applications.

Suitability of Groundwater from the Kherzet Youcef Lead-Zinc Deposit (North-Eastern Algeria) for Irrigation and Drinking Water Supply

As part of the hydro geological study of the Kherzet Youcef deposit, a drilling battery was carried out. The objective of this achievement is the satisfaction of the water needs of the city of Ain Azel (drinking water supply, irrigation and industrial water supply) and even the transfer to other municipalities suffering by the lack of water and the resumption of mining activity at the deposit of Kherzet Youcef. This water table is located in carbonate formations of Paleo-Neogene age linked to lead-zinc mineralization. Knowledge of water quality and its suitability for human consumption is an obligation. These metals have adverse health effects. We used the results of Sonarem’s analyses from 1973 to 1979. In addition, we carried out two analyses, during two years 2015-2016, on five boreholes. The parameters analyzed are major elements, physical parameters and trace metal elements (Zn, Pb and Fe). The analyses were done by ICP-AES. In our work, it has been shown that waste water is suitable for use in agriculture. For this we used the electrical conductivity at 25°C and those of the sodium adsorption ratio (SAR). For drinking water supply, monitoring the change in trace metal element (Zn, Pb and Fe) for two years has allowed us to conclude that groundwater in the groundwater table east of the Kherzet Youcef fault is generally acceptable. They are eligible by the quality standard set by Algerian regulations. However, they exceed the world health organization (WHO) standards, especially for lead. We recommend a revision of drinking water quality standards set by Algerian regulations, rigorous monitoring of TME content variation and water treatment before distribution.

Impact of Salinity on Respiration and Organic Matter Dynamics in Soils is More Closely Related to Osmotic Potential than to Electrical Conductivity

Osmotic potential （OP） of soil solution may be a more appropriate parameter than electrical conductivity （EC） to evaluate the effect of salts on plant growth and soil biomass. However, this has not been examined in detail with respect to microbial activity and dissolved organic matter in soils with different texture. This study evaluated the effect of salinity and sodicity on respiration and dissolved organic matter dynamics in salt-affected soils with different texture. Four non-saline and non-sodic soils differing in texture （S-4, S-13, S-24 and S-40 with 4%, 13%, 24~ and 40~~ clay, respectively） were leached using combinations of 1 mol L-1 NaC1 and 1 mol L-1 CaC12 stock solutions, resulting in EC （1：5 soil：water ratio） between 0.4 and 5.0 dS m-1 with two levels of sodicity （sodium absorption ratio （SAR） 〈 3 （non-sodic） and 20 （sodic）, 1：5 soil：water ratio）. Adjusting the water content to levels optimal for microbial activity~ which differed among the soils, resulted in four ranges of OP in all the soils： from -0.06 to -0.24 （controls, without salt added）, -0.55 to -0.92, -1.25 to -1.62 and -2.77 to -3.00 Mpa. Finely ground mature wheat straw （20 g kg-1） was added to stimulate microbial activity. At a given EC, cumulative soil respiration was lower in the lighter-textured soils （S-4 and S-13） than in the heavier-textured soils （S-24 and S-40）. Cumulative soil respiration decreased with decreasing OP to a similar extent in all the soils, with a greater decrease on Day 40 than on Day 10. Cumulative soil respiration was greater at SAR ---- 20 than at SAR 〈 3 only at the OP levels between -0.62 and -1.62 MPa on Day 40. In all the soils and at both sampling times, concentrations of dissolved organic C and N were higher at the lowest OP levels （from -2.74 to -3.0 MPa） than in the controls （from -0.06 to -0.24 MPa）. Thus, OP is a better parameter than EC to evaluate the effect of salinity on dissolved organic matter and microbial activity in different textured soils.