Several BrRe(CO)3L complexes (where L groups are 2,2'-biquinoline substituted in the 3 and 3' positions) were prepared. Their pseudooctahedralfuc structure was established by using FTIR, UV-vis, and 1H-NMR and confirmed by X-ray analysis. A good correlation between the electrochemical parameters and the MLCT electronic transition was found. The crystalline compound, BrRe(C0)3(3,3'-trimethylene-2,2'-biquinoline) belongs to triclinic space groupPiwitha=9,113(11)A,b= 10.192(4)A,c= 12.825(5)A,ar=73.23(4)0,B=81.30(7)0,andy=66.55(5)0.The volume of the unit cell is 1048(1) A3 with Z = 2. The structure was refined to R = 0.040.

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Arsenic is the most important contaminant of the environment in northern Chile. Soil samples and plant organs from three native plant species, Pluchea absinthioides, Atriplex atacamensis and Lupinus microcarpus, were collected from arid zones in order to determine the total and bioavailable arsenic concentrations in soils and to assess the bioconcentration factor (BCF) and transport index (Ti) of arsenic in the plants. Total arsenic concentrations in soils (pH 8.3-8.5) where A. atacamensis and P. absinthioides were collected, reached levels considered to be contaminated (54.3 ± 15.4 and 52.9 ± 9.9 mg kg⁻¹, respectively), and these values were approximately ten times higher than in soils (pH 7.6) where L. microcarpus was collected. Bioavailable arsenic ranged from 0.18 to 0.42% of total arsenic concentration. In the three plant species, arsenic concentration in leaves were significantly (p ≤ 0.05) higher than in roots. L. microcarpus showed the highest arsenic concentration in its leaves (9.7 ± 1.6 mg kg⁻¹) and higher values of BCF (1.8) and Ti (6.1), indicating that this species has a greater capacity to accumulate and translocate the metalloid to the leaf than do the other species.

Lithium−manganese ferrite LiFeMnO4 was prepared using two different methods: a conventional ceramic high-temperature solid-state reaction technique (Cer) and thermal decomposition of metal nitrate salts (NTD). The characterization of the compounds was carried out by SEM/EDX, XRD, XPS, Fe K- and Mn K-edge XANES, and Mössbauer spectroscopy. Both Cer and NTD LiFeMnO4 samples have the nominal expected Fe/Mn atomic ratio and show a homogeneous morphology, but they exhibit different particle sizes. Fe K-edge XANES and Mössbauer spectroscopy results show that the oxidation state of Fe ions is +3 in both samples, whereas the Mn K-edge XANES data indicate that the bulk average Mn oxidation state is +3 for the NTD sample and close to +4 for the Cer one. Thus, to maintain the charge neutrality, the NTD sample has to be nonstoichiometric in oxygen with a composition close to LiFeMnO3.5. The Mn 3s XPS data indicate that the average surface oxidation state of Mn is also lower in the NTD sample. The results suggest the occurrence of small Fe clusters inside the spinel-related structure in both samples. The Fe cluster occurrence can be due to the presence of diamagnetic Li+ ions, which share both tetrahedral and octahedral sites with the Fe3+ ions. This can result in different configurations around the Fe-occupied sites such that some of the Fe3+ ions located at the octahedral sites remain in a paramagnetic state at 298 K and, therefore, are responsible for the doublet observed in the corresponding Mössbauer spectrum. The neighboring Mn-rich regions containing Mn3+ or Mn4+ ions in octahedral positions also modify the existing magnetic interactions in such a way that they become more complex in the NTD sample than in the Cer one, which is reflected in a more marked superparamagnetic-like behavior. This suggests the existence in the NTD sample of a larger amount of Fe clusters, which can be explained by the different oxidation states of Mn, a larger number of oxygen vacancies, and a higher number of Fe sites with reduced coordination in this material. Finally, the differences found in the chemical and structural properties of Cer and NTD samples can be due not only to variations in thermal treatments used in each synthesis procedure but also to the different nature of the starting products in both methods.

The aim of this study was to estimate both the contribution of drinking water and food (raw and cooked) to the total (t-As) and inorganic (i-As) arsenic intake and the exposure of inhabitants of Socaire, a rural village in Chile´s Antofagasta Region, by using urine as biomarker. The i-As intake from food and water was estimated using samples collected between November 2008 and September 2009. A 24-hour dietary recall questionnaire was given to 20 participants. Drinking water, food (raw and cooked) and urine samples were collected directly from the homes where the interviewees lived. The percentage of i-As/t-As in the drinking water that contributed to the total intake was variable (26.8–92.9). Cereals and vegetables are the food groups that contain higher concentrations of i-As. All of the participants interviewed exceeded the reference intake FAO/OMS (149.8 µg∙i-As·day−1) by approximately nine times. The concentration of t-As in urine in each individual ranged from 78 to 459 ng·mL−1. Estimated As intake from drinking water and food was not associated with total urinary As concentration. The results show that both drinking water and food substantially contribute to i-As intake and an increased exposure risk to adult residents in contaminated areas.