We have described the development of electrochemical nano sensor for the detection of total arsenic in groundwater, soil, food and honey samples based on the formation of gold nanoparticles. Screen printed carbon electrodes were modified with gold nanoparticles and linked with 1,6-hexanedithiol self-assembled monolayers. The electrodeposition of Au nanoparticles was applied in 10 mL of the solution that totally cover the screen-printed carbon electrode while applying a constant potential of –0.4 V (vs. Ag within SPCE) for 600 sec. Cyclic voltammetry was used to characterize the gold nanoparticles before and after modified with 1,6-hexanedithiol self-assembled monolayers on screen printed carbon electrode. Square wave anodic stripping voltammetry with multi point standard addition method was examined for the detection of As(III) and As(V) on Au NPs-1,6-hexanedithiol modified screen printed carbon electrode under optimized conditions. As(III) and As(V) was firstly, deposited for 60 seconds by the reduction of arsenic in buffer solution: (citric acid, sodium chloride and ascorbic acid pH 2.0), followed by As stripping between –0.20 and 0.35 V at the following parameters: scan rate: 100 mV s–1, frequency: 60 Hz, amplitude: 0.025 V and increment: 5.0 mV. it was found that Au-NPs with 1,6-hexanedithiol modified screen-printed carbon electrode had a highest anodic stripping peak current at 0.201 V. The limit of detection value for arsenic was identified to be 1.7 ng ml –1. Also, the electrochemical nanosensor showed excellent reproducibility and high stability. The developed method was successfully applied to detect total arsenic in ground water, soil and honey samples.

This study had been performed in Sabratha area to assign some physical, chemical and biological characteristics for underground water and to find out its propriety for drinking. The study area was divided into ten locality: Dahman, Al- Khatatba, Aljabbar, Subratha center, Soug Al-Alalgah, Aldababshiah, Alnahdah, Tillil, Altunaibat, and Aggar. Forty eight samples of underground water has been collected in the study area. Five wells from each site were chosen except in Subratha center, where three wells were chosen. After performing the necessary analysis it became clear that the total dissolved salts concentration in 93.75% of the wells exceeded the allowable limit for drinking water, the highest was found to 4444.060 PPM in Tillil area, in addition to that, it was found that 81.25% of the wells, water, exceeded the allowable limits for sulpher concentration in drinking water. It was found that the concentration of the chloride (Cl ‾) exceeded the allowable limit for drinking water in 93.75 % of the wells, and the concentration of nitrite (NO2‾) exceeded the allowable limit in 8.3 % of the wells, while the concentration of nitrate ion ( NO3‾ ), in all wells were compatible with the Libyan and International specifications. The Calcium ion (Ca+2) exceeded the allowable limit in 87.5% of the wells. We can found also that, the concentration of magnesium element (Mg) exceeded the allowable limit in 79.1% of the wells. As for the sodium (Na+) concentration, it exceeded the allowable limit for drinking water in 95.8% of the wells, the highest was recorded in Sabratha center (7782 ppm). Some of the wells were polluted from the biological aspect, that was due to the contamination by sewage waters. In this study we found that, 39.58% of the well waters were polluted and not compatible to the international and Libyan standard specifications for drinking water, while we found that 60.41% of the wells were not polluted and were compatible with the standards. From the chemical aspect we found that, the most wells in the study area were not good for drinking, especially those located to the north, since they are near the sea and they merge with sea water . We also can notice that many of the wells were not good for drinking from the biological aspect, so we recommend to perform chemical and biological analysis before using the underground waters for domestic, agricultural and industrial objectives. Key words: Underground water, chemical pollution, biological pollution, Sabratha, Libya

Evapotranspiration calculation is an important matter due to agricultural reasons, but also for understanding water resources and runoff amount in a certain territory. Two CMIP5 multimodal projections (2011–2040 and 2041–2070) and land-cover pattern were used to analyse the seasonal and annual crop evapotranspiration trend in Turkey. The spatial distribution of crop evapotranspiration related to the initial season, mid-season, end season and cold season were computed through a geographical information system. The maximum crop evapotranspirations were found in the mid-season for present and future, with 1,072 and 1,241 mm respectively. For the future period, an increase in the spatial distribution of crop evapotranspiration was depicted in several places due to climate warming, mainly in the southern and southeastern areas of Turkey and on the Mediterranean coast. The minimum seasonal crop evapotranspirations fell to below 154 and 164 mm in the present and future respectively. The annual crop evapotranspiration increased from 1,675 to 1,944 mm from present to future and the significant values of absolute changes were identified in the western, eastern and southeastern regions of Turkey. The findings are useful for scientists in the climate, hydrology and agriculture fields, but also for management decisions.

This paper presents a simple approach to characterize the effects of scattering objects around indoor links at 28 GHz while the link is fully blocked by a human body. The effects of scattering objects nearby the link were studied by conducting measurements with a metallic re ector and the human body.

This present paper includes a detailed evaluation of specific biomarkers together with stable carbon isotope (δ13C) by gas chromatography-mass spectrometry (GC–MS) and Gas Chromatograph– Isotope Ratio Mass Spectrometry (GC–IR–MS). Eight crude oil samples were collected from the A, B, H (east) and H (west) Fields, located in the Murzuq Basin, Libya. Stable Carbon isotope data (δ13C) together with biomarker ratios data of individual hydrocarbons, n-alkanes, isoprenoids, terpenes, hopanes, steranes and aromatic have been determined in crude oils to delineate their bacterial degradation, source facies, organic matter precursors, depositional conditions and a variation of maturation. Based on source-specific parameters including n-C19 alkane, % C27S, %C28S, %C29S, %C23TT, %C30αβ, %rC28, DBT/P, CPI, Pr/Ph, Ts/Tm, dh 30/h 30, 1 MN, 2 MN, 26-27 DMN, 15 DMN, 236 TMN, 146-135 TMN, 125 TMN, 136 TMN ratios and δ13C‰ of saturates and aromatics fractions. Such oils showed non-biodegradation, n-C19 peak proved oils generated from a Lower Palaeozoic source rocks as emphasizedvian-C19 peak, the dominance of C29steranes

over C27 and C28 with light Carbon isotope ratio (δ13C‰) values. The abundances of isosterane C29, C27, C28.Tricyclohexaprenol and bacteriohopane polyols and aminopolyols, recommended as mixture bioprecursors of tricyclic terpenes and hopanes, furthermore regular sterane ratio gives values characteristic of Lower Palaeozoic marine source rocks and holding green algae and most likely a quantity of contribution from acritarchs. Carbon preference indices (CPIs)>0.9 pointed to an anoxic deposition, dibenzothiophene to phenanthrene (DBT/Prange 0.49 - 0.58) recommend a siliciclastic source rather than carbonate and/or evaporate saline deposition. The ratios of CPIs, pristane/n-C17 and phytane/n-C18, n-alkanes (C16 to C22) against (C23 to C33), Ts/Tm, C30diahopane/C30hopane, methylnaphthalene, dimethyl naphthalene and trimethyl naphthalene indicated that the oils analysed are mature except the B Field oil being slightly less mature than the A, H (east) and H (west) Fields oils

Series of incubation experiments were conducted to study the effect of three different organic amendments (olive waste, compost and lemon waste) on some chemical properties of calcareous soil. Soil samples were collected from northwestern coast of Egypt (Borg El Arab) from the surface soil (0-30 cm). The samples were then air-dried and then grinded, sieved (2 mm) and analyzed some physical and chemical properties. Samples were used in laboratory experiment, where organic amendments were applied to soil with different rates (0, 0.5 , 1, 1.5 and 2% (w w-1). The prepared pots were incubated for four months at temperature between 23 to 30°C.  After 4, 8, 12 and 16 weeks of the incubation, the soil samples were taken for analysis soil pH, electrical conductivity (EC) and total equivalent calcium carbonate. The results showed that compost, olive waste and lemon waste could change the chemical properties of the calcareous soils. All organic amendments caused an increase in soil EC while they slightly decreased soil pH and CaCO3 content. The compost was showed to have effectivity effect on soil pH comparing to other amendments, while lemon waste and olive waste were showed to have effectivity effect on CaCO3 content after few weeks of application. This can be explained on the basis that the olive waste and lemon waste are less biodegradable than that of compost. Finally, it is concluded that olive waste and or lemon waste can be used in preparing any compost to be more useful.