Environmental impact of cement dust pollution on foliar physiology, growth and yield of some commonly cultivated vegetable crops in Kashmir Himalayan Valley, India

The present paper evaluates the results of field experiments conducted during two consecutive growth seasons (2008–2009) to assess the environmental impact of cement dust pollution on foliar physiology (pigments), growth performance and yield of three commonly cultivated vegetable crops, tomato (Lycopersicon esculentum), radish (Raphanus sativus) and knol-khol (Brassica oleracea var. gongyloides) in Kashmir Himalayan valley, India. Two experimental sites (S1, S2) were selected in the vicinity of the cement factory at Khrew, Pulwama (Kashmir) at a distance of 0.5 km (S1) and 2 km (S2) and compared with a dust free control site (S3) located at about 6 km from the factory in a crosswind direction. The data revealed that cement dust had an adverse effect on morphological and biochemical characteristics of the crops. Differential level of crop sensitivity to cement dust was markedly evident. Knol-khol (Brassica oleracea var. gongyloides) reflected a higher degree of tolerance to particulate emissions as compared to tomato (Lycopersicon esculentum) and radish (Raphanus sativus). Photosynthetic pigment analysis showed adverse impact on chlorophyll-a, while chlorophyll-b marginally decreased in the leaves of tomato plants at S1; the effect being non-significant for the other test crops. Carotenoids also exhibited a remarkable reduction due to cement dust impact. The yield of tomato recorded severe losses (12.28–23.95%) as compared to radish (7.46–21.4%), while the effect was non-significant in knol-khol. Other growth and yield related attributes also followed a similar trend; tomato and radish showing remarkable effects in response to cement dust and knol-khol showed the least effect. The soil characteristics indicated significant reduction in available P. Except available N, other variables (pH, conductivity, available K, exchangeable Ca and Mg) recorded higher values in the polluted soils as compared to control. The need for installation of appropriate devices in cement manufacturing factories to combat the emission of dust in ambient environment together with environmental monitoring of agro-ecosystems is stressed

A compact band-notched antenna with high isolation for UWB MIMO applications

AbstractA compact antenna module with a single band notch at wireless local area network (WLAN) (5.725–5.825 GHz) for ultra-wideband (UWB) multiple input multiple output (MIMO) applications is proposed. Proposed antenna which acquires size of 0.299 λ × 0.413 λ × 0.005 λ mm3 at 3.1 GHz consists of two symmetrical radiators placed side by side on global merchandise link (GML) 1000 substrate (εr = 3.2, tan δ = 0.004). Isolation between the antenna elements is &gt;18 dB in the whole UWB band, which is achieved by introducing the vertical stub and H-slot between the monopole radiators in the ground plane. The simulated and measured results of the antenna system are in good agreement. The proposed antenna covers entire UWB with impedance bandwidth (|S11| &lt; −15 dB) from 3.1 to 11 GHz except at WLAN notched band. The designed antenna module bears low envelope correlation coefficient and minimal multiplexing efficiency hence fulfilling criteria suitable for various wireless MIMO applications.</jats:p