acidic type
Recently Published Documents


TOTAL DOCUMENTS

23
(FIVE YEARS 3)

H-INDEX

9
(FIVE YEARS 0)

2021 ◽  
Vol 6 (6) ◽  
pp. 20-30
Author(s):  
К.Е. Vedernikov ◽  

The results of a forestry and taxation study of spruce stands of the acidic type of two forest districts of the Udmurt Republic are presented. The death of the most productive spruce individuals (productivity class I–II according to B.D. Zhilkin) and pure spruce plantations (acidic forest types, I–II class of bonitet) was noted due to the mass spread of bark beetle typographus (Ips typographus). The most extensive processes of shrinking of plantings were noted in the forest area of coniferous-deciduous forests of Udmurtia. A decrease in completeness in some areas of spruce stands to 0,1...0,3 was revealed, as well as the accumulation of large volumes of dead wood. A change in environmental conditions was revealed due to a decrease in completeness in spruce stands, which led to the development of field grasses and the growth of soft-leaved species. Despite the fact that the peak of the bark beetle development occurred in 2013, a gradual expansion of its range was revealed both in the forest area of coniferous-deciduous forests and in the south taiga forest area of the Udmurt Republic.


2018 ◽  
Vol 1 (3) ◽  
pp. e00043
Author(s):  
V.E. Baulin ◽  
G.S. Tsebrikova ◽  
D.V. Baulin ◽  
Y.F. Al Ansary

The dissociation and complexation ability toward Cu(II) of acidic type phosphoryl-containing podands – tetrabasic 1,5-bis[2-(dioxyphosphoryl)-4-ethylphenoxy]-3-oxapentane (L1), dibasic – 1,5-bis[2-(ethoxyhydroxyphosphoryl)-4-ethylphenoxy]-pentane (L2) and also of their carboxylic analogue dibasic 1,5-bis[2-(oxycarbonylphenoxy)]-3-oxapentane (L3) were investigated by spectrophotometric, conductometric and potentiometric methods in water in the presence 5% of dimethyl formamide. Spectrophotometric and conductometric titration data provided evidence for formation of 1:1 (M:L) complexes. The dissociation constants were determined and species distribution diagrams for studied acids were obtained by potentiometric method. These data are of interest for the design of binary extragents and medicinal drugs based on the studied ligands. The stability constants of Cu(II) 1:1 (M:L) complexes were estimated. Analysis of the titration curves suggests that deprotonation forms of the studied ligands react with Cu2+. Substitution of carboxylic groups in acyclic polyesters by phosphonic results in increased stability of the copper(II) complexes


2017 ◽  
Vol 38 (9-10) ◽  
pp. 1325-1333 ◽  
Author(s):  
Jiao Zeng ◽  
Shengquan Liu ◽  
Menglin Wang ◽  
Shouzhuo Yao ◽  
Yingzhuang Chen

2004 ◽  
Vol 49 (4) ◽  
pp. 85-90 ◽  
Author(s):  
P.L. Yue ◽  
J.Y. Feng ◽  
X. Hu

A laponite RD clay-based Fe nanocomposite (Fe-Lap-RD) has been synthesized by the so-called pillaring technique. The X-ray diffraction (XRD) results reveal that the Fe-Lap-RD mainly consists of Fe2O3 (maghemite) crystallites and Fe2SiO10(OH)2 (iron silicate hydroxide) crystallites, respectively. The photo-catalytic activity of the Fe-Lap-RD for the degradation of an organic azo dye Orange II is examined. It is found that the rate of mineralization of Orange II is slower than that of discoloration. Under optimal conditions, 100% color and 70% total organic carbon (TOC) of 0.2 mM Orange II can be removed in 45 and 90 minutes, respectively. In addition, the performance of a strongly acidic type of ion exchange resin based catalyst as a heterogeneous photo-Fenton catalyst for the degradation of salicylic acid is also discussed.


Sign in / Sign up

Export Citation Format

Share Document