2,026,210 research outputs found
Evaluation of Homogeneity from Ore-bodied in Nigeria for Secondary Mineral Prospective
Samples from ore–bodied areas at different locations in Papalanto and Ifo in Ogun-State, South-West of
Nigeria, where Ewekoro cement industry is situated, were analyzed so as to recover some secondary
minerals of economic value. The following parameters were evaluated, conductivity, turbidity, colour, pH
and other chemical parameters. Variations of Dissolved Oxygen (DO), Chemical Oxygen Demand (COD),
sulphate, nitrate, phosphate, chloride ion contents, and temperature were also studied. Mineral-forming
heavy metals were in the ranges Fe: 89.0–1080 mg/l; Mg: 869–1120 mg/l; Pb: 23–80 mg/l; Zn: 180-480
mg/l. The concentration of nitrate is 20-35 mg/l; phosphate: 8-80mg/l; Dissolved Oxygen (DO): 30–45
mg/l; Total Dissolved Solids (TDS): 89-900 mg/l; pH: 6.1-8.5; Conductivity: 10-18ÎĽs/cm3 and temperature
ranged between 25-27oC. Also in the tabulation are the results of the homogeneity of four geochemical
explorations from other Nigerian ore-bodied environments for comparison. Correlations of some of the
physical and chemical parameters have been established with the view of providing conditions for the
formation of secondary minerals and the types of such minerals expected from the studied areas. The
minerals may include the following groups of minerals: Adelite, Melilite, Cancrinite and Copriapite. The
study apart from the present knowledge on ore-based baseline also present information on the pollution
studies of the area under investigatio
Electrochemical SERS spectra of isonicotinic acid analyzed under a photoinduced charge-transfer mechanism
Isonicotinic (IN) acid is one of the three monocarboxilic derivatives of pyridine in which the acid group is located in para-position of the heterocyclic ring. It is a weak acid (pK2=4.86) and therefore, it is not completely ionized in neutral aqueous solutions, being the zwitterion and the anion the majority chemical species at neutral pH. In acidic solutions (pK1=1.84) the pyridinic nitrogen atom can be protonated yielding a third chemical species with positive charge [1].
In addition, IN acid shows two functional centres that can interact with the silver metallic surface such as the carboxilate group and the aromatic nitrogen atom. Therefore, the analysis of the SERS spectra of IN has been focused on identifying the chemical species adsorbed on the silver surface and its centre of interaction by considering the participation of a photoinduced charge-transfer (CT) mechanism in each particular SERS record as we have previously detected in the SERS of pyridine derivatives [2].
SERS spectra of the IN acid (5x10-3 M) have been recorded on silver at electrode potentials ranging from 0.00 up to -1.00 V and at different pH by using 0.1 M Na2SO4 aqueous solution as electrolyte. The figure shows the SERS recorded at basic pH. The experimental set up is described elsewhere and the excitation line of 514.5 nm wavelength was used. [2]. The detection of the presence of CT processes, which are similar to resonance Raman, requires to carry out quantum mechanical calculations [2].Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tec
The gamma-ray burst monitor for Lobster-ISS
Lobster-ISS is an X-ray all-sky monitor experiment selected by ESA two years
ago for a Phase A study (now almost completed) for a future flight (2009)
aboard the Columbus Exposed Payload Facility of the International Space
Station. The main instrument, based on MCP optics with Lobster-eye geometry,
has an energy passband from 0.1 to 3.5 keV, an unprecedented daily sensitivity
of 2x10^{-12} erg cm^{-2}s$^{-1}, and it is capable to scan, during each orbit,
the entire sky with an angular resolution of 4--6 arcmin. This X-ray telescope
is flanked by a Gamma Ray Burst Monitor, with the minimum requirement of
recognizing true GRBs from other transient events. In this paper we describe
the GRBM. In addition to the minimum requirement, the instrument proposed is
capable to roughly localize GRBs which occur in the Lobster FOV (162x22.5
degrees) and to significantly extend the scientific capabilities of the main
instrument for the study of GRBs and X-ray transients. The combination of the
two instruments will allow an unprecedented spectral coverage (from 0.1 up to
300/700 keV) for a sensitive study of the GRB prompt emission in the passband
where GRBs and X-Ray Flashes emit most of their energy. The low-energy spectral
band (0.1-10 keV) is of key importance for the study of the GRB environment and
the search of transient absorption and emission features from GRBs, both goals
being crucial for unveiling the GRB phenomenon. The entire energy band of
Lobster-ISS is not covered by either the Swift satellite or other GRB missions
foreseen in the next decade.Comment: 6 pages, 4 figures. Paper presented at the COSPAR 2004 General
Assembly (Paris), accepted for publication in Advances in Space Research in
June 2005 and available on-line at the Journal site
(http://www.sciencedirect.com/science/journal/02731177), section "Articles in
press
\u3ci\u3eTownshend v. Townshend\u3c/i\u3e & \u3ci\u3eButtar v. Buttar\u3c/i\u3e: Gifts, Exclusions, and Intentions
This comment looks at two fairly recent decisions by the Ontario Court of Appeal, Townshend v Townshend (2012 ONCA 868) and Buttar v Buttar (2013 ONCA 617) with respect to the courts\u27 handling of the exclusion of gifts under section 4(2) of Ontario\u27s Family Law Act (RSO 1990, c F.3). In Ontario, gifts made by third parties outside the marriage to one spouse may be excluded from the calculation of a spouse\u27s Net Family Property (NFP). Property may cease to be excludable if it is not kept separate or if it is used to the benefit of the family. In both Townshend and Buttar, the court had to grapple with fungible gifts and decide to what degree the gifts should be excluded from the NFP calculations. In both decisions, the courts relied upon a line of reasoning that placed too much weight on the intentions of the donor when deciding whether (or to what extent) to exclude the gifts while simultaneously undervaluing the subsequent behaviour of the donees after delivery of the gift. One worry these decisions raise is that, if donees of gifts may rely merely on the fact of a gift and not on their actions subsequent to delivery of the gift, litigants will become emboldened to find far more “gifts” among their property. Even more worrisome, however, is that the courts may be willing to grant exclusions regardless of post-delivery behaviour and thereby undermine the purpose of the NFP calculations: namely, as the preamble of the Family Law Act says, to allow the court to order an “equitable settlement of the affairs of the spouses”
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