Consideration of Total Ion Composition in Designing Toxicity Tests Using Aluminum Salts and Mineral Acids

2008 ◽  
pp. 92-92-6
Author(s):  
RC Young
Keyword(s):  
Toxicity Tests ◽  
Ion Composition ◽  
Aluminum Salts ◽  
Mineral Acids

scholarly journals Response of Atmospheric Methane Consumption by Maine Forest Soils to Exogenous Aluminum Salts

2000 ◽  
Vol 66 (9) ◽  
pp. 3674-3679 ◽  
Author(s):  
K. Nanba ◽  
Gary M. King
Keyword(s):  
Soil Ph ◽  
Forest Soils ◽  
Aluminum Chloride ◽  
Atmospheric Methane ◽  
Aluminum Salts ◽  
Methane Consumption ◽  
Ph Values ◽  
Mineral Acids ◽  
Sulfate Salts

ABSTRACT Atmospheric methane consumption by Maine forest soils was inhibited by additions of environmentally relevant levels of aluminum. Aluminum chloride was more inhibitory than nitrate or sulfate salts, but its effect was comparable to that of a chelated form of aluminum. Inhibition could be explained in part by the lower soil pH values which resulted from aluminum addition. However, significantly greater inhibition by aluminum than by mineral acids at equivalent soil pH values indicated that inhibition also resulted from direct effects of aluminum per se. The extent of inhibition by exogenous aluminum increased with increasing methane concentration for soils incubated in vitro. At methane concentrations of >10 ppm, inhibition could be observed when aluminum chloride was added at concentrations as low as 10 nmol g (fresh weight) of soil−1. These results suggest that widespread acidification of soils and aluminum mobilization due to acid precipitation may exacerbate inhibition of atmospheric methane consumption due to changes in other parameters and increase the contribution of methane to global warming.

Study of the radiomodifier effect of Pityrocarpa moniliformis extract

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
João Victor Torres de Moraes ◽  
Ricardo Luiz Calazans Luna Filho ◽  
Williams Nascimento de Siqueira ◽  
Hianna Arely Milca Fagundes Silva ◽  
Dewson Rocha Pereira ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Cellular Response ◽  
Biomphalaria Glabrata ◽  
Toxicity Tests ◽  
Antioxidant Compounds ◽  
Blastula Stage ◽  
Natural Substances ◽  
60Co Source ◽  
60Co Gamma ◽  
60Co Gamma Radiation

Ionizing radiation has been applied in several areas of knowledge, among them the study of the radiomodifier activity of natural substances. These substances can modify the cellular response to the damage induced by the radiation. Therefore, this work aimed to evaluate the radiomodifier action of Pityrocarpa moniliformis extract on Biomphalaria glabrata embryos exposed to 60Co gamma radiation. Initially, toxicity tests were performed on the extract against the B. glabrata embryos for the choice of concentration that did not cause death and embryonic malformation. Then, the antioxidant activity of the P. moniliformis extract with flavonoids and phenolic compounds was evaluated by means of the ABTS method. To evaluate the radiomodifier activity of the extract, embryos were selected in the blastula stage and irradiated with 7.5 Gy in a 60Co source (gammacell-Co60). Then, the embryos were exposed for 24 h to the extract of P. moniliformis at a concentration of 250 μg/mL. The results showed that the extract of P. moniliformis presents flavonoids and enzymatic inhibition by ABTS, which demonstrates the presence of antioxidant compounds. However, the tests of the radiomodifier activity did not present radioprotective effect for embryos exposed to ionizing radiation.

Impact of filters of varying cleaning degrees on ion composition of air

2016 ◽  
Vol 0 (6) ◽  
Author(s):  
Valery G. Marchenko ◽  
Anatoliy E. Lagytin ◽  
Alexander I. Lipa ◽  
Anatoliy P. Ponomarenko
Keyword(s):  
Ion Composition

Structural and Magnetic Hysteresis Properties of Co-Zr Substituted Hexagonal Barium Ferrites

2015 ◽  
Vol 7 (1) ◽  
pp. 1346-1351
Author(s):  
Ch.Gopal Reddy ◽  
Ch. Venkateshwarlu ◽  
P. Vijaya Bhasker Reddy
Keyword(s):  
Magnetic Properties ◽  
Single Phase ◽  
Magnetic Hysteresis ◽  
Grain Morphology ◽  
Hexagonal Structure ◽  
Ion Composition ◽  
X Ray Diffraction ◽  
Ceramic Method ◽  
Barium Ferrites ◽  
Xrd Patterns

Co-Zr substituted M-type hexagonal barium ferrites, with chemical formula BaCoxZrxFe12-2xO19 (where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), have been synthesized by double sintering ceramic method. The crystallographic properties, grain morphology and magnetic properties of these ferrites have been investigated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM). The XRD patterns confirm the single phase with hexagonal structure of prepared ferrites. The magnetic properties have been investigated as a function of Co and Zr ion composition at an applied field in the range of 20 KOe. These studies indicate that the saturation magnetization (Ms) in the samples increases initially up to the Co-Zr composition of x=0.6 and decreases thereafter. On the other hand, the coercivity (Hc) and Remanent magnetization (Mr) are found to decrease continuously with increasing Co-Zr content. This property is most useful in permanent magnetic recording. The observed results are explained on the basis of site occupation of Co and Zr ions in the samples.

NICROFER 3033

Alloy Digest ◽  
2004 ◽  
Vol 53 (2) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Heat Treating ◽  
High Chromium ◽  
Temperature Performance ◽  
Mineral Acids ◽  
Mixed Acids

Abstract Nicrofer 3033 is a high-chromium austenitic material for service in hot mineral acids and mixed acids. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-508. Producer or source: VDM Technologies Corporation. Originally published April 1996, revised February 2004. See also Alloy Digest SS-687, July 1997.

Acute and chronic effect of cyaniade on survival rate, behavior, and reproduction of Daphnia sp.

2013 ◽  
Vol 1 (1) ◽  
pp. 52 ◽  
Author(s):  
Melky R Pattiwael ◽  
Remy E. P Mangindaan ◽  
Rudi Prabowo ◽  
Inneke F. M Rumengan
Keyword(s):  
Government Regulation ◽  
Aquatic Organisms ◽  
Standard Test ◽  
Toxicity Tests ◽  
Zooplankton Organism ◽  
Rate Behavior ◽  
Negative Impacts ◽  
Reproduction Pattern ◽  
Acute And Chronic Effects ◽  
Ministerial Decree

Cyanide (CN) through leaching process in the gold processing could produce tailings that have negative impacts on the aquatic environment. To determine the acute and chronic effects of cyanide on aquatic organisms, toxicity tests have been conducted in the laboratory using Daphnia sp.This zooplankton organism is recommended by APHA as standard test animals. In this study the test concentrations refer to the Ministerial Decree No. 202 of 2004 and Government Regulation No. 82 of 2001. Cyanide was analyzed as free CN and WADS CN. The result of acute toxicity test using cyanide solution showed that Daphnia could survive a maximum concentration of 0.2 ppm. LC50 values for 24 and 72 hours were 0,59 mg/L and 0,10 mg/l, respectively. The LT50 was found at 42 hours. Daphnia sp. produced different numbers of offspring at different CN concentrations, and changed their reproduction pattern from parthenogenesis to sexual reproduction after exposure to a cyanide concentration of 0.1 ppm for 24 hours©  Sianida (CN) melalui proses leaching dalam proses pengolahan emas menghasilkan limbah yang dapat memberi dampak negatif bagi lingkungan perairan. Untuk mengetahui sampai seberapa jauh CN dapat memberi efek akut dan kronis terhadap biota air, telah dilakukan uji toksisitas di laboratorium dengan menggunakan Daphnia sp. Zooplankton ini direkomendasikan oleh APHA sebagai salah satu hewan uji standar. Dalam penelitian ini konsentrasi uji yang dipakai mengacu pada peraturan yang berlaku, yaitu Keputusan Menteri No. 202, Tahun 2004, dan Peraturan Pemerintah No. 82, Tahun 2001. Analisis sianida yang dihitung adalah nilai free CN dan WADS CN. Hasil penelitian uji toksisitas akut dengan menggunakan larutan sianida didapati Daphnia mampu bertahan hidup sampai pada konsentrasi 0,2 ppm dan nilai LC50 berada pada konsentarsi 0,1 ppm serta LT50 pada jam ke 42. Hasil uji efek kronis, Daphnia sp. menghasilkan jumlah anakan yang berbeda pada konsentrasi CN yang berlainan, dan mengalami perubahan pola reproduksi dari partenogenesis menjadi seksual setelah dipaparkan pada kosentrasi sianida 0,1 ppm selama 24 jam©

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