Soil is a key carbon reservoir balancing global budget and regulating climate change. Barren soils in karst zones have weak capacity for soil water conservation are readily erodible, making the biogeochemical processes within potentially rapid complex. To explore vertical variation of under conditions its response to land-use change, this study investigated concentrations isotopic compositions ...

Cinnabar (α-HgS) is the most common sulfide of mercury while metacinnabar (β-HgS), a high-temperature homogeneous polymorph sulfide, relatively rare, and α phase cinnabar transforms to β at 344 °C. Meanwhile, there complete isomorphic series between HgS HgSe, occurrence Se-bearing great significance for exploration selenium resources. We studied through microscopic observation, electron-probe m...

The Salobo iron oxide copper-gold (IOCG) deposit host an important Cu-mineralization of the Carajás Mineral Province. ore is characterized by association (bornite-chalcocite-digenite) hosted magnetite and biotite-garnet schists. These rocks record distinct stages superimposed hydrothermal alteration dynamic metamorphism. Three different occurrences constitute bodies: a pristine to inclusion-poo...

Disposing of plastic wastes to landfill is becoming undesirable due to legislation pressures, rising costs and the poor biodegradability of commonly used polymers. In addition, incineration meets with strong societal opposition. Therefore, recycling either mechanical or chemical, seems to be the only route of plastic wastes management towards sustainability. Polyolefins, mainly polyethylene (LD...

Tourmalines are a group of minerals which may concentrate various accessory 16 components, e.g. Cu, Ni, Zn, Bi, Ti, Sn. The paper presents fluor-elbaite and elbaite from a dyke of 17 the Julianna pegmatitic system at Piława Górna, at the NE margin of the Bohemian Massif, SW 18 Poland, containing up to 6.32 and 7.37 wt.% ZnO, respectively. Such high amounts of ZnO are 19 almost two times higher ...

Currently, performance assessment (PA) modelling for nuclear waste repositories reliesheavily on the Kd approach which empirically averages contaminant retardation over a range ofconditions in the hope that uncertainties are treated conservatively. Mechanistic approaches arerare or non-existent, often because of lack of information. However, recently developed high-resolution, s...

Iron (hydr)oxides not only serve as potent sorbents and repositories for nutrients and contaminants but also provide a terminal electron acceptor for microbial respiration. The microbial reduction of Fe (hydr)oxides and the subsequent secondary solid-phase transformations will, therefore, have a profound influence on the biogeochemical cycling of Fe as well as associated metals. Here we elucida...

Dense machinable α-SiAlON/BN composites were fabricated by hot-pressing using turbostratic boron nitride (tBN) obtained from nitridation of melamine diborate. The tBN was added to the starting powders, or introduced as a coating that formed in situ on α-Si3N4 carrier powders during nitridation, and was subsequently converted to hexagonal boron nitride (hBN) during hot pressing by solution repre...

size reduction of high energy materials such as 1, 3, 5, 7-tetranitro- 1, 3, 5, 7-tetraaza cyclooctane (hmx) has considerable influences on improving their explosive characteristics. in this study, nanosized hmx par­ticles were produced using ultrasonically reprecipitation method by applying water as a safe and accessible antisolvent instead of unsafe conventional methods. sem photographs revea...

Biogenic opal produced by vascular plants, diatoms, and siliceous sponges have been found in soils and terrestrial sediments of all continents except Antarctica since the middle of the 19th century. The opal particles range in size from fine silt to fine sand. Almost all soils contain detectable opal up to levels of 2–3%, and a significant number contain values in excess of 5%. Even higher valu...