Water is essential for humans, animals, and plants; pollutants, usually derived from anthropogenic activities, can have a serious effect on its quality. Heavy metals are significant pollutants and are often highly toxic to living organisms, even at very low concentrations. Among the numerous removal techniques proposed, adsorption onto suitable adsorbent materials is considered to be one of the most promising. The objective of the current study was to determine the effectiveness of halloysite nanotubes (HNT) functionalized with organic amino or thiol groups as adsorbent materials to decontaminate polluted waters, using the removal of Hg2+ ions, one of the most dangerous heavy metals, as the test case. The effects of pH, ionic strength (I), and temperature of the metal ion solution on the adsorption ability and affinity of both materials were evaluated. To this end, adsorption experiments were carried out with no ionic medium and in NaNO3 and NaCl at I = 0.1 mol L−1, in the pH range 3–5 and in the temperature range 283.15–313.15 K. Kinetic and thermodynamic aspects of adsorption were considered by measuring the metal ion concentrations in aqueous solution. Various equations were used to fit experimental data, and the results obtained were explained on the basis of both the adsorbent’s characterization and the Hg2+ speciation under the given experimental conditions. Thiol and amino groups enhanced the adsorption capability of halloysite for Hg2+ ions in the pH range 3–5. The pH, the ionic medium, and the ionic strength of aqueous solution all play an important role in the adsorption process. A physical adsorption mechanism enhanced by ion exchange is proposed for both functionalized materials.

Clays are used in various cosmetic formulations, such as sunscreens, toothpastes, deodorants, creams, hair cosmetics, makeups, nail polish, facial masks, and shampoos, among others, to improve the organoleptic and physicochemical characteristics, to increase the stability, or to facilitate elaboration. Together with their technological functionalities, clays are cosmetologically active ingredients with cleaning, anti-aging, anti-wrinkling, and sun-care functionalities. Talc, kaolinite, mica, and some smectites are the clay minerals used most frequently in cosmetic products, but several other phyllosilicates as well as modified and synthetic clays are also used. Sometimes, clays are useful in the design of cosmetics just because they are made of rigid, small, and anisometric particles. Kaolinite and mica are made of hard prismatic particles which are lightly abrasive over the skin, teeth, or hair. Electric charges in smectites result in ion-exchange capacities useful in the loading of active cosmetics but also adsorbing and cleaning waste substances. Intermediate net negative charges of smectites result in layer expansion in polar media and specific rheological properties that are very useful in cosmetic formulations. The absence of charged particles in talc and kaolin make them flow easily resulting in lubricant effects. Protection against radiation from the sun by clay particles and decorative effects complete the possibilities of clays in cosmetics. The nomenclature for clays used as ingredients in cosmetics follows historical use and the names of commercial products, rather than following strict compositional principles. In this sense, an effort was made here to correlate the names of the minerals that make up each of the clay-based cosmetic ingredients.

The present study examines the effectiveness of an online standardizedtreatment of posttraumatic stress and pathological grief administeredthrough the Internet. Twenty students who had experienced traumatic lifeevents and showed the symptoms of posttraumatic stress participated in thestudy. They received credit course points for inclusion in theresearch. Treatment consisted of 10 writing sessions (45 minutes each)during a period of 5 weeks. Participants were assessed at pretreatment,posttreatment, and after six weeks (follow-up). The participants improvedstrongly from pre- to post-treatment on posttraumatic stress andpathological grief symptoms and in psychological functioning. Theseimprovements were sustained during the follow-up period. Moreover, 19 ofthe 20 participants were clinically recovered after treatment. The changesin posttraumatic stress symptomatology were compared post hoc to changes incontrol and experimental groups from trials on similarly protocolled butface-to-face treatment of posttraumatic stress.