Reacted copper(II) concentrations in earlywood and latewood of micronized copper-treated Canadian softwood species

Holzforschung ◽  
2015 ◽  
Vol 69 (4) ◽  
pp. 509-512 ◽  
Author(s):  
Wei Xue ◽  
Pierre Kennepohl ◽  
John N.R. Ruddick

Abstract Electron paramagnetic resonance was used in conjunction with X-ray fluorescence spectroscopy to quantify total copper and reacted copper retentions in MCQ and MCA treated Canadian red pine sapwood and western hemlock heartwood. Total copper retentions were distinctly different between earlywood and latewood of both softwood species examined. Earlywood of red pine sapwood had higher total copper content than the latewood, while western hemlock heartwood had higher total copper contents in latewood than earlywood. The reacted copper concentrations were similar in earlywood and latewood, reflecting a similar capacity of each to solubilize and complex the reacted copper.

2006 ◽  
Vol 295 (1) ◽  
pp. 135-140 ◽  
Author(s):  
Kátia Cylene Lombardi ◽  
Antonio Salvio Mangrich ◽  
Fernando Wypych ◽  
Ubirajara Pereira Rodrigues-Filho ◽  
José L. Guimarães ◽  
...  

Crystals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 637
Author(s):  
Natalia Tereba ◽  
Tadeusz M. Muzioł ◽  
Robert Podgajny ◽  
Grzegorz Wrzeszcz

In this paper, three new heterometallic compounds were described and compared with the molecular formula [Cu(pn)2Zn(NCS)4] (1), [Cu(N,N-Me2-en)2Zn(NCS)4] (2), [Cu(N-Me-en)2Zn(NCS)4]∙½H2O (3) where pn = 1,2−diaminopropane, N,N-Me2-en = N,N‒dimethylethylenediamine and N-Me-en = N-methylethylenediamine, respectively. The compounds mentioned above were characterized by elemental analysis, infrared (IR), electronic, electron paramagnetic resonance (EPR) spectra, and magnetic studies. Crystal structures for 1 and 2 were determined by X-ray analysis. Copper(II) in these complexes adopts 4 + 2 coordination with two elongated (in 2 very long and considered as semi-coordination) Cu-S bonds. The Cu-N and Cu-S bond lengths depend on substituent position affecting steric hindrance and hence a topology of the chain. Both chains form different zigzag patterns characterized by one or two Cu-Zn distance values. Weak magnetic interaction is observed, ferromagnetic in the case of 1 and antiferromagnetic in the case of 2, due to diversity of the above structural features.


Holzforschung ◽  
2013 ◽  
Vol 67 (7) ◽  
pp. 815-823 ◽  
Author(s):  
Wei Xue ◽  
Pierre Kennepohl ◽  
John N.R. Ruddick

Abstract Sapwood sawdust from southern pine was treated with micronized copper (MC) under various conditions and the mobilized copper(II) (Cumob) concentrations were determined in the treated wood by electron paramagnetic resonance (EPR) spectroscopy. The spectral parameters for the copper sulfate (CuSO4)-treated sapwood and those of the MC-treated sapwood were very similar. A linear correlation was found between the intensities of copper (Cu) EPR spectra and those of Cu energy-dispersive X-ray fluorescence spectroscopy in a series of CuSO4-treated sapwood reference samples. Thus, the EPR signal intensities could be reliably correlated to the mass of reacted Cu present using this calibration curve. The amount of the Cumob in sawdust treated by MC suspensions increased during the first 2–3 days after the initial treatment and then reached a maximum during the 7-day monitoring period. In the case of the treatment with MC alone or MC azole, an increased MC concentration led to an elevated amount of Cu (to a maximum of ∼0.23% Cu) solubilized by the sapwood. If the wood was treated with MC quat, the Cumob initially increased, but at higher concentrations the Cumob content decreased, due to the interference by the quat cobiocide on the acid reaction between the wood and the basic Cu carbonate. An examination of commercially-treated wood confirmed the laboratory observations.


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