“Measure my teeth and you'll know what I ate”: The molar ratio method and an updated interpretation of the diet of Nyctereutes sinensis (Carnivora, Canidae)

2019 ◽  
Vol 100 (2) ◽  
pp. 211-215 ◽  
Author(s):  
Saverio Bartolini Lucenti
Proceedings ◽  
2019 ◽  
Vol 41 (1) ◽  
pp. 77 ◽  
Author(s):  
Hamad M. I. Hasan ◽  
Aaza I. Yahiya ◽  
Safaa S. Hassan ◽  
Mabrouk M. Salama

Adenine complexes were prepared with some of the first series transition metals in a stoichiometric ratio of 1: 2 (Mn+: L), where Mn+ = Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, and Cd2+ ions. The Complexes were characterized by the physicochemical and spectroscopic techniques as electric conductivity, metal contents, IR, UV–Visible, and molar conductance techniques. The stoichiometric ratios of the synthesized complexes were confirmed by using molar ratio method. The dissociation constant of adenine ligand was determined spectrophotometrically. Solvent effect on the electronic spectra of the adenine ligand was examined using solvents with different polarities. The biological activity of adenine ligand and its metal complexes were tested in vitro against some selected species of fungi and bacteria. The results showed a satisfactory spectrum against the tested organisms.


2016 ◽  
Vol 98 (3) ◽  
pp. 292-299 ◽  
Author(s):  
Masakazu Asahara ◽  
Masanaru Takai

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Xiang Cheng ◽  
Yan Huang ◽  
Hui Li ◽  
Fan Yue ◽  
Hongmei Wen ◽  
...  

This paper introduces the structural characterization and studies on reversible oxygenation behavior of a new oxygen carrier Co(II)-2,4-diaminobutanoic acid (DABA) complex in aqueous solution. The composition of the oxygenated complex was determined by gas volumetric method, molar ratio method, and mass spectrometry, and the formula of the oxygenated complex was determined to be [Co(DABA)2O2]. In aqueous solution, the complex can continuously uptake and release dioxygen and exhibit excellent reversibility of oxygenation and deoxygenation ability. This complex can maintain 50% of its original oxygenation capacity after 30 cycles in 24 h and retain 5% of the original oxygenation capacity after more than 260 cycles after 72 h. When a ligand analogue was linked to histidine (His), the new complex exhibited as excellent reversible oxygenation property as His-Co(II) complex. Insight into the relationship between structural detail and oxygenation properties will provide valuable suggestion for a new family of oxygen carriers.


2012 ◽  
Vol 9 (4) ◽  
pp. 668-679 ◽  
Author(s):  
Baghdad Science Journal

All the prepared metal complexes of Pt (IV), Au(III), Rh (III), Co (II) and V(IV) with new ligand sodium [5-(p-nitro phenyl)-/4-phenyl-1,2,4-triazole-3-dithiocarbamato hydrazide] (TRZ.DTC) have been synthesized and characterized in solid state by using flame atomic absorption, elemental analysis C.H.N.S, FT-IR ,UV-Vis Spectroscopy, conductivity and magnetic susceptibility measurements. The nature of the complexes formed in ethanolic solution has been studied following the molar ratio method also was studied stability constant and found to be stable in molar ratio1:1 of VL (IV) and CoL(II) while Pt(IV), Au(III) and Rh(III) complexes stable in molar ratio 1:2 as well as the molar absorptivity for these complexes were calculated. From the previous analyses, octahedral geometry was suggested for Pt (IV), Rh (III) and Co (II) complexes, square planar was suggested for Au(III) complex while V(IV) complex has a square pyramidal. Cytotoxic effect of PtL, AuL and RhL as well as ligand has been evaluated against RD cell line by using four different concentrations (500, 250, 125 & 62.5 µg/ml) respectively in three exposure times 24, 48 and 72 hrs and compared this effect with control positive Cis-Pt.


Author(s):  
Salwa Fares Rassi

A simple, rapid and sensitive spectrophotometric method was developed for the determination of Se (IV) using 5,6-diaminouracil hydrochloride (DAUH) as an analytical reagent. The reagent has been synthesized and characterized using IR, 1H NMR. The metal ion in aqueous medium forms yellow colored complex with DAUH showing maximum absorbance at 343 nm. Hence, analytical studies were further carried out at 343 nm. The reagent reacts with selenium in acidic medium to form yellow colored 1:1 (M:L) complex . The color reactions are instantaneous and absorbance values remain constant for one week. The composition of the Se (IV) complex with DAUH was studied by the method of job’s continuous variation and molar ratio method. Beer’s law was obeyed in the range 0.2-15.0 μg mL−1of Se (IV). The molar absorptivity and Sandell’s sensitivity of the method were found to be 0.5×10+4 L.mol-1.cm-1and 0.031μg.cm-2 respectively. Since DAUH method is more sensitive, it was applied for the determination of selenium in samples.


1982 ◽  
Vol 47 (8) ◽  
pp. 2110-2120 ◽  
Author(s):  
Jaromíra Chýlková ◽  
Václav Říha ◽  
Stanislav Kotrlý

Colour reactions of 7-(o-carboxyphenylazo)-8-hydroxyquinoline-5-sulphonic acid (OKFAZOX) with various metal ions are described. The formation of copper(II) complexes has been studied spectrophotometrically within a wide pH range by molar ratio method using computer-assisted regression matrix analysis of the absorbance sets. The following complexes have been identified, in agreement with the results of non-linear regression of continuous variation plots, as predominating species: CuLH2 within pH 1.3-2.9; CuLH within pH 3-7. Then, between pH 7 and 10, the complexes CuL and CuL2 take part in a stepwise equilibrium. Relevant conditional stability constants have been determined. A new photometric EDTA microtitration of copper(II) using OKFAZOX as indicator is proposed with the following optimum arrangement: pH about 5 (acetate buffer) and ionic strength 0.01; indicator concentration approx. 5 μmol l-1 or slightly higher; absorbance followed at 510 nm. End-point extrapolation gives precise results even within micromolar range:e.g. 2 μmol l-1 Cu2+ can be determined with a relative error less than 2%.


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