Dead leaves of seagrass Posidonia oceanica were activated by using one mol L −1 acetic acid and used as an eco-adsorbent for the removal of methylene blue (MB) and Pb 2+ from aqueous solutions. The seagrass was characterized by chemical and physical measurements that confirmed the acid-activation of seagrass. The favourable conditions for MB and Pb 2+ adsorption onto the activated seagrass (SG a ) were determined to be a pH range of 2–12 and ≥6, an adsorbent dosage of 3.0 and 0.5 g L −1 , respectively, and a shaking time of 30 min, which are suitable for a wide range of wastewaters. The equilibrium data were analysed using the Langmuir, Freundlich and Dubinin-Raduskavich-Kaganer (DRK) adsorption isotherm models. The Freundlich and DRK models best describe the adsorption processes of MB and Pb 2+ , on SG a with capacities of 2681.9 and 631.13 mg g −1 , respectively. The adsorption isotherm fitting and thermodynamic studies suggest that the adsorption mechanism of MB may combine electrostatic and physical multilayer adsorption processes, in which MB may be present as monomers as well as dimers and trimers which were confirmed from UV spectroscopy whereas Pb 2+ is chemically adsorbed onto SG a . The pseudo-2 nd -order kinetic model was utilized to investigate the kinetics of adsorption processes. The removal process was successfully applied for MB-spiked brackish waste water from Manzala Lake, Egypt, with removal efficiencies of 91.5–99.9%.

Heavy metal contamination of land and freshwater resources is a serious concern worldwide. It adversely affects the health of animals, plants and humans. Therefore, remediation of toxic heavy metals must be highly considered. Unlike other techniques, phytoremediation is a holistic technology and can be used in large scale for soil remediation as it is costless, novel, environmentally-safe and solar-driven technology. Utilization of non-edible plants in phytoremediation is an ingenious technique as they are used to generate new bioenergy resources along with the remediation of contaminated soils. Some nonfood bioenergy crops such as Salix species, Miscanthus species, Populus species, Eucalyptus species, and Ricinus communis exhibit high capability to accumulate various metals and to grow in contaminated lands. However, there are still sustainable challenges facing coupling phytoremediation with bioenergy production from polluted lands. Therefore, there has long been a need for developing different strategies to resolve such challenges. In this article review, we will discuss the phytoremediation mechanism, the technique of phytoremediation coupling with bioenergy production, sustainable problems facing linking phytoremediation with energy production as well as possible strategies to enhance the efficiency of bioenergy plants for soil decontamination by improving their characteristics such as metal uptake, transport, accumulation, and tolerance.

Rice straw (RS) collected from Egyptian agricultural environment (Al-Masied village-Alsharqia Governorate-Egypt) was used as substrate for three fungal isolates namely: 4b, 1Asp, Pleurotus ostreatus NRRL 3501 and mixed culture of (4b, 1Asp). Isolates number 4b and 1Asp were identified using the molecular technique (18S rRNA). Isolate 4b and 1Asp, were identified as Trichoderma saturnisporum MN1-EGY and Aspergillus niger MN2-EGY, respectively. Trichoderma saturnisporum MN1-EGY extract exhibited the highest antimicrobial activity compared to the other fungal extracts. Total phenolic, antimicrobial and antioxidant activities were also determined from the ethyl acetate extract of rice straw inoculated by these fungi. The antioxidant scavenging concentration(SC50) values of the tested samples were 88.84, 91.45, 94.65 and 100.0µg/ml, respectively for Pleurotus sp., Aspergiluus niger, Aspergiluus niger + Trichoderma sp., and Trichoderma sp., after 15 days incubation, compared to ascorbic acid as positive control with SC50 value equal to 8.0 µg/ml. Total phenolic contents (TPCs) were maximum in Pleurotus sp. extract and found to be the most polyphenolic enriched sample (380.64 mg GAE/g dry extract) compared to extracts of Aspergiluusniger, Aspergiluus niger + Trichoderma sp., and Trichoderma sp. (261.89, 198.52, and 119.80 mg GAE/g dry extract), respectively. The GC-MS analysis has been also performed for the promising extracts.

Compressive Sensing (CS) is a digital signal processing developed theory that encloses the signal sampling and compression, based on the sparsity characteristics of signal. This can decrease sampling rate, so reduce computational complexity of the system without degrading the performance of the system. This paper describes the theoretical frame and a few key technical, then illustrates the application of compressed sensing theory to wide-band cognitive radio signals. Spectrum sensing is a critical issue in wide-band Cognitive Radio (CR) networks as it faces hard challenges such as high hardware cost, complexity, sampling rate and processing speed. Thus, this paper shows that Compressive Sensing could be exploited in wide-band Cognitive Radio networks to solve the spectrum sensing problems mentioned above.