Caddisfly larvae construct underwater protective cases using surrounding materials, thus providing information on environmental conditions in both modern and ancient systems. Microbial bioherms associated with caddisfly cases are found in the Berriassian-Hauterivian (~140-130 Ma) Shinekhudag Formation of Mongolia, and yield new insights into aspects of lacustrine paleoecosystems and paleoenviro...

The bioavailability and fractionation of Cu reflect its deliverability in soil. Little research has investigated Cu supply to crops in soil under long-term rotation and fertilisation on the Loess Plateau. A field experiment was conducted in randomized complete block design to determine the bioavailability and distribution of Cu fractions in a Heilu soil (Calcaric Regosol) after 18 years of rota...

13ETIiRMINATION of total iodine in various materials has become of increasing interest, especially in nutritional studies. Several methods are available for such determination. Many of them have been principally concerned with the protein-bound iodine fraction in serum (1, 2). Other methods for iodine determination have appeared from time to time. Mathews et al. (3) have proposed a method which...

OBJECTIVE To investigate the relationship between copper speciation and microbial features (microbial communities and copper tolerance level) in order to determine the adverse effect of different forms of Cu on microorganisms. METHODS Tessier's sequential extraction procedure was used to qualify the different Cu forms (exchangeable, carbonate bound, Fe/Mn oxide bound, residue and organic matt...

Speciation of coal cotton ash from Okaba in Kogi State Nigeria was carried out using flame atomic absorption spectrometry. Results of this research showed that the elements studied (Cr, Fe, Cu, Ni, Pb, Cd and Zn) were all observed in at least three fractions of the sequential extraction procedure. Pb showed more presence in the exchangeable fraction (80±0.03 μg/g) which is a serious problem to ...

Gases contained within near-surface marine sediments can be derived from multiple sources: shallow microbial activity, thermal cracking of organic matter and inorganic materials, or magmatic-mantle degassing. Each origin will display a distinctive hydrocarbon and non-hydrocarbon composition as well as compound-specific isotope signature and thus the interpretation of origin should be relatively...

the concentrations of potentially toxic elements (as, sb, and hg) and some trace elements in 36 topsoil samples and 18 agricultural soil samples were measured at the aq-darreh river watershed, nw iran. based on the results of the chemical analysis and comparing them with different standards, it seems that the soils of the aq-darreh river watershed are polluted with as and sb. this pollution res...

The quantitative description of the interactions of uranium with blood serum components is of high relevance for a rational design of molecules suitable for in vivo chelation of uranium. We have determined the stability constants for the complexation of U(VI) with human serum transferrin and albumin by time-resolved laser-induced fluorescence spectroscopy and difference ultraviolet spectroscopy...

We examined the use of room-temperature hydrochloric acid (1-6 M) and salt solutions of magnesium chloride, sodium carbonate, and sodium sulfide for the removal of arsenic from synthetic iron monosulfides and contaminated sediments containing acid-volatile sulfides (AVS). Results indicate that acid-soluble arsenic reacts with H2S released from AVS phases and precipitates at low pH as disordered...