scholarly journals REUSE OF THE AQUEOUS PHASE OF BIO-OIL FRACTIONATION AS A WATER-REPELLENT AGENT FOR WOOD

FLORESTA ◽  
2021 ◽  
Vol 51 (3) ◽  
pp. 557
Author(s):  
Caio Silvestre Lima Sanson ◽  
Ivana Amorim Dias ◽  
Marina Gorgete Santos ◽  
Bruno De Miranda ◽  
Pedro Henrique Gonzalez de Cademartori

A simple method to extract pyrolytic lignin from bio-oil is under agitation in water or organic solvent. This process produces a water-insoluble fraction (pyrolytic lignin) and a water-soluble fraction (WS). In this study, we used a physical fractionation technique with water as a liquid agent to separate the two fractions of the fast pyrolysis bio-oil and obtain the WS — the object of study — to test its efficiency as a protective agent for lignocellulosic materials. The study aimed to investigate the efficiency of the aqueous phase (WS) as a water-repellent agent when impregnated into Pinus elliotti wood. To obtain WS, we used two bio-oil:water ratios (1:50 and 1:100) and two agitation speeds (17,000 and 8,500 RPM); they were respectively named WS50 and WS100, both with an average yield of 61% WS. Gas chromatography coupled with mass spectrometry (GC-MS), thermogravimetry (TGA), contact angle, and scanning electron microscopy (SEM) were used to characterize the WS and the veneers impregnated with it. There were no morphological changes on their surface, especially regarding the non-coating of the wood pits; meanwhile, the TGA showed visible changes in the degree of thermal degradation of the impregnated material related to the chemical composition of the WS identified in the GC-MS. There was a significant increase, on average 62%, in the apparent contact angle of the impregnated wood, approximately 126°. The WS has shown to be efficient as a protective agent by converting the hydrophilic surface of Pinus elliotti into a hydrophobic one, and this effect partially remained after 45 days of exposure.

2022 ◽  
Vol 177 ◽  
pp. 114540
Author(s):  
Caio Silvestre Lima Sanson ◽  
Cristiane Vieira Helm ◽  
Washington Luiz Esteves Magalhães ◽  
Graciela Inés Bolzon de Muniz ◽  
André Luiz Missio ◽  
...  

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1915 ◽  
Author(s):  
Eyob Wondu ◽  
Hyun Woo Oh ◽  
Jooheon Kim

In this study water-soluble polyurethane (WSPU) was synthesized from isophorone diisocyanate (IPDI), and polyethylene glycol (PEG), 2-bis(hydroxymethyl) propionic acid or dimethylolpropionic acid (DMPA), butane-1,4-diol (BD), and triethylamine (TEA) using an acetone process. The water solubility was investigated by solubilizing the polymer in water and measuring the contact angle and the results indicated that water solubility and contact angle tendency were increased as the molecular weight of the soft segment decreased, the amount of emulsifier was increased, and soft segment to hard segment ratio was lower. The contact angle of samples without emulsifier was greater than 87°, while that of with emulsifier was less than 67°, indicating a shift from highly hydrophobic to hydrophilic. The WSPU was also analyzed using Fourier transform infrared spectroscopy (FT-IR) to identify the absorption of functional groups and further checked by X-ray photoelectron spectroscopy (XPS). The molecular weight of WSPU was measured using size-exclusion chromatography (SEC). The structure of the WSPU was confirmed by nuclear magnetic resonance spectroscopy (NMR). The thermal properties of WSPU were analyzed using thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).


2014 ◽  
Vol 1061-1062 ◽  
pp. 170-174
Author(s):  
Jian Li

The effects of surface treatment of a carbon fiber (CF) by Polyethylene-polyamine (PEPA) on the interfacial adhesion behavior and morphology of polypropylene/polystyrene (PP/PS) matrix blends filled CF composites were investigated. Effects of surface treated a commercial CF on mechanical properties are studied. Contact angle was measured to examine the changes in wettability of the carbon fiber. The chemical and morphological changes were characterized by using X-ray photoelectron spectroscopy (XPS). PP/PS/CF composites were fabricated with and without PEPA treatment, and their interlaminar fracture toughnesses were compared. The results showed that the interlaminar shear strength (ILSS) of composites has been greatly improved filled PEPA modification CF. The water contact angle of resin sample decreased 50% after addition of PEPA surface treated CF.


1997 ◽  
Vol 124 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Hao Ding ◽  
Jianxing Kang ◽  
Brian E. Hanson ◽  
Christian W. Kohlpaintner

2006 ◽  
Vol 290 (4) ◽  
pp. F789-F794 ◽  
Author(s):  
Yasin Tayem ◽  
Tony R. Johnson ◽  
Brian E. Mann ◽  
Colin J. Green ◽  
Roberto Motterlini

Nephrotoxicity is one of the main side effects caused by cisplatin (CP), a widely used antineoplastic agent. Here, we examined the effect of a novel water-soluble carbon monoxide-releasing molecule (CORM-3) on CP-mediated cytotoxicity in renal epithelial cells and explored the potential therapeutic benefits of carbon monoxide in CP-induced nephrotoxicity in vivo. Exposure of LLC-PK1 cells to CP (50 μM) caused significant apoptosis as evidenced by caspase-3 activation and an increased number of floating cells. Treatment with CORM-3 (1–50 μM) resulted in a remarkable and concentration-dependent decrease in CP-induced caspase-3 activity and cell detachment. This effect involved activation of the cGMP pathway as 1H-oxadiazole [4, 3-a] quinoxaline-1-ore (ODQ), a guanylate cyclase inhibitor, completely abolished the protection elicited by CORM-3. Using a rat model of CP-induced renal failure, we found that treatment with CP (7.5 mg/kg) caused a significant elevation in plasma urea (6.6-fold) and creatinine (3.1-fold) levels, which was accompanied by severe morphological changes and marked apoptosis in tubules at the corticomedullary junction. A daily administration of CORM-3 (10 mg/kg ip), starting 1 day before CP treatment and continuing for 3 days thereafter, resulted in amelioration of renal function as shown by reduction of urea and creatinine levels to basal values, a decreased number of apoptotic tubular cells, and an improved histological profile. A negative control (iCORM-3) that is incapable of liberating CO failed to prevent renal dysfunction mediated by CP, indicating that CO is directly involved in renoprotection. Our data demonstrate that CORM-3 can be used as an effective therapeutic adjuvant in the treatment of CP-induced nephrotoxicity.


1998 ◽  
Vol 275 (1) ◽  
pp. F143-F153 ◽  
Author(s):  
L. B. Zimmerhackl ◽  
F. Momm ◽  
G. Wiegele ◽  
M. Brandis

Cadmium toxicity to renal cells was investigated in Madin-Darby canine kidney (MDCK) and LLC-PK1cells as models of the distal tubule/collecting duct and proximal tubule, respectively. Cells were grown on two-compartment filters and exposed to 0.1–50 μM Cd2+. In MDCK cells, Cd2+was more toxic from the basolateral than from the apical side and dependent on the extracellular Ca2+concentration. Toxicity was evident within 24 h, as shown by a decrease in transepithelial resistance (TER), reduced proliferation (bromodeoxyuridine incorporation), reduction in ATP concentration, and morphological changes. On confocal microscopy, E-cadherin and α-catenin staining patterns indicated interference with the cadherin-catenin complex. LLC-PK1cells showed a similar toxicity pattern, which was evident at lower Cd2+concentrations. An increase of E-cadherin and α-catenin molecules in the Triton X-100-insoluble fraction was detectable at high Cd2+concentrations in LLC-PK1cells but not in MDCK cells. Lactate dehydrogenase release indicated membrane leakage in LLC-PK1cells. Rhodamine-phalloidin staining, a probe for F-actin filaments, demonstrated alterations of the actin cytoskeleton in both cell lines. In conclusion, cadmium caused ATP depletion and interfered with the cadherin-catenin complex and probably the tight junctions changing renal cell morphology and function.


2013 ◽  
Vol 13 (2) ◽  
pp. 1023-1037 ◽  
Author(s):  
C. Mouchel-Vallon ◽  
P. Bräuer ◽  
M. Camredon ◽  
R. Valorso ◽  
S. Madronich ◽  
...  

Abstract. The gas phase oxidation of organic species is a multigenerational process involving a large number of secondary compounds. Most secondary organic species are water-soluble multifunctional oxygenated molecules. The fully explicit chemical mechanism GECKO-A (Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere) is used to describe the oxidation of organics in the gas phase and their mass transfer to the aqueous phase. The oxidation of three hydrocarbons of atmospheric interest (isoprene, octane and α-pinene) is investigated for various NOx conditions. The simulated oxidative trajectories are examined in a new two dimensional space defined by the mean oxidation state and the solubility. The amount of dissolved organic matter was found to be very low (yield less than 2% on carbon atom basis) under a water content typical of deliquescent aerosols. For cloud water content, 50% (isoprene oxidation) to 70% (octane oxidation) of the carbon atoms are found in the aqueous phase after the removal of the parent hydrocarbons for low NOx conditions. For high NOx conditions, this ratio is only 5% in the isoprene oxidation case, but remains large for α-pinene and octane oxidation cases (40% and 60%, respectively). Although the model does not yet include chemical reactions in the aqueous phase, much of this dissolved organic matter should be processed in cloud drops and modify both oxidation rates and the speciation of organic species.


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