Quercetin-imprinted poly(vinyl pyridine-co-ethylene glycol dimethacrylate) cross-linked grafts were prepared by atom transfer radical polymerization (ATRP) using aryl modified gold substrates as macroinitiators. The aryl layers were first attached to Au by electrochemical reduction of the diazonium salt BF The changes in the surface chemical composition, from the neat Au to Au-MIP and Au-NIP, were monitored by XPS and polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS). Cyclic voltammetry (CV) was used to assess the specificity and selectivity of Au-MIP to detect quercetin. The detection limit was found to be better than 10 −6 mol/l with CV.

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This study aims to discriminate and to map the basement rocks as well as the barite mineralization exposed at El Hudi area, Southeastern Desert, Egypt using the processed short-wave infrared bands of advanced spaceborne thermal emission and reflection radiometer (ASTER) in collaboration with the field verification and petrographic analysis. El Hudi area is covered dominantly by the Late Precambrian high-grade metamorphic complex of metasedimentary rocks (gneisses, schists, migmatites, and minor amphibolites) which are intruded by the younger granitoids. Nubian sandstones unconformably overlie the basement outcrops and occur as a remnant caps. The metasedimentary rocks cover the area of interest forming a belt of biotite gneisses and migmatites intercalated with hornblende biotite schists and minor amphibolites. Their exposures exhibit well-foliated and banded structures. The metasedimentary rocks have gray and dark gray image signatures on the ASTER band ratio image 8/5, which correspond to biotite gneiss, migmatites, and hornblende biotite schists, respectively. Presence of absorption feature near band 8 (2.295 -2.365 μm) for the chlorite alteration product is probably responsible for the lowering of the 8/5 band ratio value and the dark gray image signature exhibited by hornblende biotite schists. The granitoid rocks in El Hudi area are late to postorogenic younger granitoids including three main rock types, Abu Aggag granites, El Hudi garnetiferous muscovite granites, and coarse-grained biotite granites. The acidic dykes are cutting across the granitoids and the gneisses and they form a highly elevated ridges and peaks showing sharp contact with the invaded rocks. Abu Aggag granites are highly dissected by great number of both strike-and dip-slip faults as well as joints trending in NNW-SSE, NNE-SSW, N-S, ENE-WSW, and WNW-ESE directions. On 7/8 band ratio image, Abu Aggag granites have dark gray image signature whereas postgranitic dykes have white image signature. Under the microscope, Abu Aggag granites are homogenous medium to coarse-grained rocks composed mainly of quartz, plagioclase, microcline, and biotite. Zircon, apatite, and opaques are accessories, while chlorite, kaolinite, and epidote are secondary minerals. Presence of absorption feature around band 7 (2.235-2.285 μm) for the kaolinite mineral may be responsible for the dark gray image signature exhibited by Abu Aggag granites. El Hudi garnetiferous muscovite granites are hosting El Hudi barite veins which extend mainly in NNW-SSE and NW-SE. Garnetiferous muscovite granites have gray image signature on 5/4 band ratio image whereas pegmatites and postgranitic dykes have black image signature. Barite veins can be distinguished within garnetiferous muscovite granites by their dark gray image signature on 5/4 band ratio image. The spectral reflectance curve of barite exhibits absorption feature around 2.1 μm (band 5), which leads to lower the ratio value and yields the dark image signature to barite veins. The above-described ASTER band ratio images ...

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In the present study, remote sensing techniques, GIS models and field measurements are integrated to identify and map groundwater potential zones at Wadi Yalamlam (Sa'diyah) basin, Makkah Province, Western Saudi Arabia. The study area is located in the Arabian Shield heterogeneous basement terrain. It is characterized by insignificant primary porosity and permeability and is mainly covered by massive and altered gneissose granites, diorite, and gabbro and metamorphosed basalts. Lithology, rainfall, lineament density, drainage density, slope steepness and landuse/landcover are the main hydrogeological parameters defined to be related to the groundwater storage in the study area. They are prepared using the processed satellite data and integrated using weights of evidence and index overlay GIS models to generate groundwater potential zones map. Within the GIS model, those parameters are assigned values of 30, 20, 15, 15, 10 and 10, respectively, as score values. The resulting groundwater potential zone map for Wadi Yalamlam basin is categorized into three main classes (high, moderate and low groundwater potential zones) based on pixel values. The results of this study indicate that the lower parts of the Wadi Yalamlam basin is the most promising area for groundwater occurrences and contains both high and moderate potential zones. High groundwater potential zones are located to the north of the main dyke area around Abu Helal farm. They are characterized by loose wadi deposits, flat areas, gentle slope (ranges between 0 and 5 degrees), low drainage density (\100 D/30 km 2 ) and shallow water table (water table is 7 m from the ground surface). The present study proved: (1) the usefulness of the processed remote sensing satellite imageries for generating several indirect groundwater parameters; (2) the usefulness of weights of evidence and index overlay GIS models for the integration process and the production of groundwater potential zone map along the study area.

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