Interest in perchlorate as environmental pollutant has increased since 1997, when high concentrations have been found in the waters of the Colorado River, USA. Perchlorate is very persistent in nature and it is slowly degraded. Although harmful effects of large doses of perchlorate on thyroid function have been proven, the environmental effects are still unclear. The primary objective of the present review is to collect prevailing data of perchlorate exposure and to discuss its impact on human health. The results show that more than 50% of reviewed works found significant associations of perchlorate exposure and human health. This review consists of the following sections: general information of perchlorate sources, its properties and determination methods, role and sources in human body including food and water intake, overview of the scientific literature on the research on the effect of perchlorate on human health from 2010 to 2020. Finally, conclusions and recommendations on future perchlorate studies concerning human exposure are presented.

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A hyper-crosslinked resin chemically modified with thiourea (TM-HPS) was synthesized, characterized, and evaluated for the removal of heavy metal ions (Pb 21 , Cd 21 , and Cu 21) from aqueous solutions. The structural characterization results showed that a few thiourea groups were grafted on the surface of the resin with a big BET surface area and a large number of narrow micropores. Various experimental conditions such as pH, contact time, temperature, and initial metal concentration of the three heavy metal ions onto TM-HPS were investigated systematically. The results indicated that the prepared resin was effective for the removal of the heavy metal ions from aqueous solutions. The isotherm data could be better fitted by Langmuir model, yielding maximum adsorption capacities of 689.65, 432.90, and 290.69 mg/g for Pd 21 , Cd 21 , and Cu 21 , respectively. And the adsorption kinetics of the three metal ions followed the pseudo-second-order equation. FTIR and XPS analysis of TM-HPS before and after adsorption further revealed that the adsorption mechanism could be a synergistic effect between functional groups and metal ions and electrostatic attraction, which may provide a new insight into the design of highly effective adsorbents and their potential technological applications for the removal of heavy metal ions from aqueous solutions.

The crystal structure of the new phase Er 0.85 Co 4.31 Si was determined by single-crystal X-ray diffraction (46 unique reflections, R1 = 0.0378, wR2 = 0.0697). The compound crystallizes in the TbCu 7 structure type: space group P6/mmm, hP8-1.85, with lattice parameters a = 4.8593(19), c = 3.9869(16) Å. A full investigation of the crystal structure was also performed for the known phase CoSi on single-crystal X-ray diffraction data (61 unique reflections, R1 = 0.0256, wR2 = 0.0548). CoSi crystallizes in the FeSi structure type: space group P2 1 3, cP8, with lattice parameter a = 4.4500(5) Å.

Single crystals of didysprosium aluminium digermanide were synthesized from the corresponding elements by arc‐melting in the presence of Ni. The new inter­metallic compound crystallizes in the space group P4/mbm and adopts the Mo2FeB2 structure type, with all three crystallographically unique atoms in special positions of site symmetries m.2m (Dy and Ge) and 4/m.. (Al). The coordination polyhedra around the metal atoms are distorted penta­gonal (Dy), tetra­gonal (Al) and trigonal (Ge) prisms with 7, 4 and 3 additional capping atoms, respectively.