Publications by authors named "Zhi-Lin Wu"

17 Publications

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Predicting mortality in acute ischaemic stroke treated with mechanical thrombectomy: analysis of a multicentre prospective registry.

BMJ Open 2021 04 1;11(4):e043415. Epub 2021 Apr 1.

Department of Neurology, Jinan University First Affiliated Hospital, Guangzhou, China

Objectives: We aimed to determine predictors of mortality within 90 days and develop a simple score for patients with mechanical thrombectomy (MT).

Design: Analysis of a multicentre prospective registry.

Setting: In six participating centres, patients who had an acute ischaemic stroke (AIS) treated by MT between March 2017 and May 2018 were documented prospectively.

Participants: 224 patients with AIS were treated by MT.

Results: Of 224 patients, 49 (21.9%) patients died, and 87 (38.8%) were independent. Variables associated with 90-day mortality were age, previous stroke, admission National Institutes of Health Stroke Scale (NIHSS), fasting blood glucose and occlusion site. Logistic regression identified four variables independently associated with 90-day mortality: age ≥80 years (OR 3.26, 95% CI 1.45 to 7.33), previous stroke (OR 2.33, 95% CI 1.04 to 5.21), admission NIHSS ≥18 (OR 2.37, 95% CI 1.13 to 4.99) and internal carotid artery or basilar artery occlusion (OR 2.92, 95% CI 1.34 to 6.40). Using these data, we developed predicting 90-day mortality of AIS with MT (PRACTICE) score ranging from 0 to 6 points. The receiver operator curve analysis found that PRACTICE score (area under the curve (AUC)=0.744, 95% CI 0.669 to 0.820) was numerically better than iScore (AUC=0.661, 95% CI 0.577 to 0.745) and Predicting Early Mortality of Ischemic Stroke score (AUC=0.638, 95% CI 0.551 to 0.725) for predicting 90-day mortality.

Conclusions: We developed a simple score to estimate the 90-day mortality of patients who had an AIS treated with MT. But the score needs to be prospectively validated.

Trial Registration Number: Chinese Clinical Trial Registry (ChiCTR-OOC-17013052).
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http://dx.doi.org/10.1136/bmjopen-2020-043415DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8021751PMC
April 2021

Dexmedetomidine Protects against Myocardial Ischemia/Reperfusion Injury by Ameliorating Oxidative Stress and Cell Apoptosis through the Trx1-Dependent Akt Pathway.

Biomed Res Int 2020 25;2020:8979270. Epub 2020 Nov 25.

Institute of Anesthesia and Critical Care Medicine, Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Dexmedetomidine (Dex) was reported to reduce oxidative stress and protect against myocardial Ischemia/Reperfusion (I/R) injury. However, the molecular mechanism involved in its antioxidant property is not fully elucidated. The present study was aimed at investigating whether the Trx1/Akt pathway participated in the cardioprotective effect of Dex. In the present study, I/R-induced myocardial injury in isolated rat hearts and OGD/R-induced injury in H9c2 cardiomyocytes were established. Our findings suggested that Dex ameliorated myocardial I/R injury by improving cardiac function, reducing myocardial apoptosis and oxidative stress, which was manifested by increased GSH and SOD contents, decreased ROS level, and MDA generation in both the isolated rat hearts and OGD/R-treated H9C2 cells. More importantly, it was found that the level of Trx1 was preserved, and Akt phosphorylation was significantly upregulated by Dex treatment. However, these effects of Dex were abolished by PX-12 (a specific Trx1 inhibitor) administration. Taken together, this study suggests that Dex plays a protective role in myocardial I/R injury, improves cardiac function, and relieves oxidative stress and cell apoptosis. Furthermore, our results present a novel signaling mechanism that the cardioprotective effect of Dex is at least partly achieved through the Trx1-dependent Akt pathway.
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http://dx.doi.org/10.1155/2020/8979270DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7710428PMC
June 2021

Copper(i)-catalyzed intermolecular cyanoarylation of alkenes: convenient access to α-alkylated arylacetonitriles.

Org Biomol Chem 2020 07;18(27):5234-5237

Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, Changsha University of Science and Technology, Changsha, 410114, China.

A novel Cu(i)-catalyzed intermolecular cyanoarylation of alkenes with diaryliodonium salts as a radical arylating reagent and tetra-butylammonium cyanide as an electrophilic cyanating reagent was established. A broad range of α-alkylated arylacetonitriles were efficiently constructed in good to excellent yields under base- and oxidant-free and mild conditions.
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http://dx.doi.org/10.1039/d0ob01055cDOI Listing
July 2020

CXCL14 Overexpression Attenuates Sepsis-Associated Acute Kidney Injury by Inhibiting Proinflammatory Cytokine Production.

Mediators Inflamm 2020 31;2020:2431705. Epub 2020 Mar 31.

Department of Anesthesiology, Institute of Anesthesiology and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei 430022, China.

CXCL14 is a relatively novel chemokine with a wide spectrum of biological activities. The present study was designed to investigate whether CXCL14 overexpression attenuates sepsis-associated acute kidney injury (AKI) in mice. Sepsis model has been established by cecal ligation and puncture (CLP). CLP induced AKI in mice as assessed by increased renal neutrophil gelatinase-associated lipocalin (NGAL) expression and serum creatinine levels. We found that renal CXCL14 expression in the kidney was significantly decreased at 12 hours after CLP. Correlation analysis demonstrated a negative association between renal CXCL14 expression and AKI markers including serum creatinine and renal NGAL. Moreover, CXCL14 overexpression reduced cytokine (TNF-, IL-6, and IL-1) production and NGAL expression in the kidney and decreased serum creatinine levels. and experiments found that CXCL14 overexpression inhibited M1 macrophage polarization but increased M2 polarization. Together, these results suggest that CXCL14 overexpression attenuates sepsis-associated AKI probably through the downregulation of macrophages-derived cytokine production. However, further studies are required to elucidate the underlying mechanism.
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http://dx.doi.org/10.1155/2020/2431705DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7150711PMC
February 2021

Factors influencing the improvement of neuraxial labor analgesia in China: a questionnaire survey.

Chin Med J (Engl) 2020 Mar;133(5):613-614

Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China.

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http://dx.doi.org/10.1097/CM9.0000000000000529DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7065851PMC
March 2020

Dexmedetomidine Attenuates Lipopolysaccharide Induced MCP-1 Expression in Primary Astrocyte.

Biomed Res Int 2017 14;2017:6352159. Epub 2017 Feb 14.

Department of Anesthesiology, ICU and Pain Management, Benha University Hospital, Faculty of Medicine, Benha University, Benha, Egypt.

. Neuroinflammation which presents as a possible mechanism of delirium is associated with MCP-1, an important proinflammatory factor which is expressed on astrocytes. It is known that dexmedetomidine (DEX) possesses potent anti-inflammatory properties. This study aimed to investigate the potential effects of DEX on the production of MCP-1 in lipopolysaccharide-stimulated astrocytes. . Astrocytes were treated with LPS (10 ng/ml, 50 ng/ml, 100 ng/ml, and 1000 ng/ml), DEX (500 ng/mL), LPS (100 ng/ml), and DEX (10, 100, and 500 ng/mL) for a duration of three hours; expression levels of MCP-1 were measured by real-time PCR. The double immunofluorescence staining protocol was utilized to determine the expression of 2-adrenoceptors (2AR) and glial fibrillary acidic protein (GFAP) on astrocytes. . Expressions of MCP-1 mRNA in astrocytes were induced dose-dependently by LPS. Administration of DEX significantly inhibited the expression of MCP-1 mRNA ( < 0.001). Double immunofluorescence assay showed that 2AR colocalize with GFAP, which indicates the expression of 2-adrenoceptors in astrocytes. . DEX is a potent suppressor of MCP-1 in astrocytes induced with lipopolysaccharide through A-adrenergic receptors, which potentially explains its beneficial effects in the treatment of delirium by attenuating neuroinflammation.
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http://dx.doi.org/10.1155/2017/6352159DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5329661PMC
March 2017

One-Pot Three-Component Synthesis of Novel Diethyl((2-oxo-1,2-dihydroquinolin-3-yl)(arylamino)methyl)phosphonate as Potential Anticancer Agents.

Int J Mol Sci 2016 Apr 29;17(5). Epub 2016 Apr 29.

College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.

With the aim of discovering new anticancer agents, we have designed and synthesized novel α-aminophosphonate derivatives containing a 2-oxoquinoline structure using a convenient one-pot three-component method. The newly synthesized compounds were evaluated for antitumor activities against the A549 (human lung adenocarcinoma cell), HeLa (human cervical carcinoma cell), MCF-7 (human breast cancer cell), and U2OS (human osteosarcoma cell) cancer cell lines in vitro, employing a standard 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The results of pharmacological screening indicated that many compounds exhibited moderate to high levels of antitumor activities against the tested cancer cell lines and that most compounds showed more potent inhibitory activities comparable to 5-fluorouracil (5-FU) which was used as a positive control. The mechanism of representative compound 4u (diethyl((2-oxo-1,2-dihydroquinolin-3-yl)(phenyl-amino)methyl)phosphonate) indicated that the compound mainly arrested HeLa cells in S and G2 stages and was accompanied by apoptosis in HeLa cells. This action was confirmed by acridine orange/ethidium bromide staining, Hoechst 33342 staining, and flow cytometry.
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http://dx.doi.org/10.3390/ijms17050653DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4881479PMC
April 2016

Comparison of cardiac output and hemodynamic responses of intubation among different videolaryngoscopies in normotensive and hypertensive patients.

J Huazhong Univ Sci Technolog Med Sci 2015 Jun 14;35(3):432-438. Epub 2015 Jun 14.

Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.

Tracheal intubation with Macintosh laryngoscope (MAC) might result in severe cardiovascular complications. The results of conducted studies investigating the effects of videolaryngoscopies on hemodynamic response of tracheal intubation are conflicting. We know little about the effects of videolaryngoscopies on cardiac output changes during tracheal intubation. We compared cardiac output (COP) and hemodynamic responses in normal blood pressure (n=60) and hypertensive patients (n=60) among 3 intubation devices: the MAC, the UE videolaryngoscopy ® (UE), and the UE video intubation stylet ® (VS). Cardiac index (CI), stroke volume index (SVI), heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded using LidcoRapid (V2)® preinduction, preintubation, and every minute for the first 5 min after intubation. We assessed oropharyngeal and laryngeal structures injury as well. Intubation time was significantly shorter than MAC groups (P<0.001) only in UE group of normotensive and hypertensive patients. In normotensive patients, there were no significant differences in any of COP variables or hemodynamic variables among the three devices. In hypertensive patients, SBP and DBP in the MAC group were significantly higher (P<0.05 or <0.01) than the UE and VS groups at 1, 2 and 3 min after intubation, but there were no significant differences in CI, SVI and HR among the three devices. There was no significant difference in oropharyngeal and laryngeal structures injury among all groups. It was concluded that both the UE and VS attenuate only the hemodynamic response to intubation as compared with the MAC in hypertensive patients, but not in normotensive patients.
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http://dx.doi.org/10.1007/s11596-015-1449-7DOI Listing
June 2015

Eutrophic water purification efficiency using a combination of hydrodynamic cavitation and ozonation on a pilot scale.

Environ Sci Pollut Res Int 2015 Apr 29;22(8):6298-307. Epub 2014 Nov 29.

Nanjing Institute of Environmental Sciences of the Ministry of Environmental Protection of China, Jiangwangmiao Str 8, 210042, Nanjing, China.

This paper presents the purification of eutrophic water using a combination of hydrodynamic cavitation (HC) and ozonation (O3) at a continuous flow of 0.8 m(3) h(-1) on a pilot scale. The maximum removal rate of chlorophyll a using O3 alone and the HC/O3 combination was 62.3 and 78.8%, respectively, under optimal conditions, where the ozone utilization efficiency was 64.5 and 94.8% and total energy consumption was 8.89 and 8.25 kWh m(-3), respectively. Thus, the removal rate of chlorophyll a and the ozone utilization efficiency were improved by 26.5% and 46.9%, respectively, by using the combined technique. Meanwhile, total energy consumption was reduced by 7.2%. Turbidity linearly decreased with chlorophyll a removal rate, but no linear relationship exists between the removal of COD or UV254 and chlorophyll a. As expected, the suction-cavitation-assisted O3 exhibited higher energy efficiency than the extrusion-cavitation-assisted O3 and O3 alone methods.
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http://dx.doi.org/10.1007/s11356-014-3889-1DOI Listing
April 2015

Efficacy and safety of esomeprazole with flupentixol/melitracen in treating gastroesophageal reflux disease patients with emotional disorders.

J Gastroenterol Hepatol 2014 Jun;29(6):1200-6

Background And Aim: This study was designed to demonstrate the safety and efficacy of esomeprazole combined with flupentixol/melitracen for the treatment of gastroesophageal reflux disease (GERD) patients with emotional disorders. METHODS Two hundred eighty-nine GERD patients with emotional disorders were divided randomly into two groups: group 1 received esomeprazole only (monotherapy) and group 2 received esomeprazole and flupentixol/melitracen (combination therapy). The patients' GERD questionnaire (GerdQ) and hospital anxiety and depression (HAD) scores were obtained before and after treatment. Changes in the scores, rates of symptom remission, and adverse effects were compared between the two groups.

Results: After 2 weeks of treatment, the average decrease in GerdQ score in the combination group (4.04 ± 2.34) was significantly greater than that in the monotherapy group (3.34 ± 2.74; P < 0.05). Significant differences between the two groups were also found for changes in HAD anxiety scores (5.45 ± 2.41 vs 3.34 ± 2.43, P < 0.05), depression scores (5.47 ± 2.47 vs 3.00 ± 3.28, P < 0.05), and anxiety-depression scores (5.20 ± 2.71 vs 3.60 ± 2.56, P < 0.05). The remission of symptoms (eructation, abdominal pain, anorexia, and other accompanying symptoms) in the combination group was significantly better than that in the monotherapy group, and no significant difference in the incidence of adverse events was observed between the two groups.

Conclusions: The combination therapy has better efficacy than the monotherapy in improving the symptoms of gastroesophageal reflux in patients with emotional disorders. In addition, this combination treatment is safe, with a low incidence of adverse events.
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http://dx.doi.org/10.1111/jgh.12552DOI Listing
June 2014

Inhibitory effect of selenium against Penicillium expansum and its possible mechanisms of action.

Curr Microbiol 2014 Aug 30;69(2):192-201. Epub 2014 Mar 30.

Key Laboratory of Agri-Food Safety of Anhui Province, School of Plant Protection, Anhui Agricultural University, Hefei, 230036, China,

Some organic and inorganic salts could inhibit the growth of many pathogens. Selenium (Se), as an essential micronutrient, was effective in improving the plant resistance and antioxidant capacity at a low concentration. Penicillium expansum is one of the most important postharvest fungal pathogens, which can cause blue mold rot in various fruits and vegetables. In this study, the inhibitory effect of Se against P. expansum was evaluated. The result showed that Se strongly inhibited spore germination, germ tube elongation, and mycelial spread of P. expansum in the culture medium. The inhibitory effect was positively related to the concentration of Se used. Fluorescence microscopy observation of P. expansum conidia stained with propidium iodide (PI) indicated that the membrane integrity decreased to 37 % after the conidia were treated with Se (20 mg/l) for 9 h. With the use of an oxidant-sensitive probe 2,7-dichlorofluorescin (DCHF-DA), we found that Se at 15 mg/l could induce the generation of intracellular reactive oxygen species (ROS). Furthermore, methane dicarboxylic aldehyde (MDA) content, hydrogen peroxide (H2O2), and superoxide anion (O2 (-)) production rate in P. expansum spores exposed to Se increased markedly. Compared with the control, the activities of superoxide dismutase (SOD) and the content of glutathione (GSH) were reduced, confirming that damage of Se to cellular oxygen-eliminating system is the main reason. These results suggest that Se might serve as a potential alternative to synthetic fungicides for the control of the postharvest disease of fruit and vegetables caused by P. expansum.
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http://dx.doi.org/10.1007/s00284-014-0573-0DOI Listing
August 2014

Hyperforin attenuates brain damage induced by transient middle cerebral artery occlusion (MCAO) in rats via inhibition of TRPC6 channels degradation.

J Cereb Blood Flow Metab 2013 Feb 14;33(2):253-62. Epub 2012 Nov 14.

Department of Anesthesiology and Intensive Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Hyperforin, a lipophilic constituent of medicinal herb St John's wort, has been identified as the main active ingredient of St John's wort extract for antidepressant action by experimental and clinical studies. Hyperforin is currently known to activate transient receptor potential canonical (subtype) 6 (TRPC6) channel, increase the phosphorylated CREB (p-CREB), and has N-methyl-D-aspartate receptor-antagonistic effect that convert potential neuroprotective effects in vitro. However, the protective effects of hyperforin on ischemic stroke in vivo remain controversial and its neuroprotective mechanisms are still unclear. This study was designed to examine the effects of intracerebroventricular (i.c.v.) injection of hyperforin on transient focal cerebral ischemia in rats. Hyperforin, when applied immediately after middle cerebral artery occlusion (MCAO) onset, significantly reduced infarct volumes and apoptotic cells, and also increased neurologic scores at 24 hours after reperfusion accompanied by elevated TRPC6 and p-CREB activity and decreased SBDP145 activity. When MEK or CaMKIV activity was specifically inhibited, the neuroprotective effect of hyperforin was attenuated, and we observed a correlated decrease in CREB activity. In conclusion, our results clearly showed that i.c.v. injection of hyperforin immediately after MCAO onset blocked calpain-mediated TRPC6 channels degradation, and then to stimulate the Ras/MEK/ERK and CaMKIV pathways that converge on CREB activation, contributed to neuroprotection.
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http://dx.doi.org/10.1038/jcbfm.2012.164DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3564196PMC
February 2013

Sonoelectrochemical degradation of phenol in aqueous solutions.

Ultrason Sonochem 2013 Mar 24;20(2):715-21. Epub 2012 Sep 24.

Institute for Technical Chemistry and Environmental Chemistry, Friedrich-Schiller University Jena, Lessingstr. 12, 07743 Jena, Germany.

The sonoelectrochemical degradation of phenol in aqueous solutions with stainless steel electrodes and high-frequency ultrasound (850kHz) was investigated. A 60% synergetic effect was obtained in the combined reaction system. High concentration of electrolyte (sodium sulfate) and a high electrical voltage are favorable conditions for the degradation of phenol. A nearly complete degradation of phenol was achieved with 4.26g/L Na(2)SO(4) and 30V electrical voltages at 25°C in 1h. The degradation of phenol follows pseudo-first order kinetics. Considering costs and application, the energy efficiency of the reaction system with different reaction conditions was evaluated.
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http://dx.doi.org/10.1016/j.ultsonch.2012.09.004DOI Listing
March 2013

Enhancement of chloroform degradation by the combination of hydrodynamic and acoustic cavitation.

Ultrason Sonochem 2011 Jul 13;18(4):888-94. Epub 2010 Dec 13.

Institute of Technical Chemistry and Environmental Chemistry, Friedrich-Schiller-University Jena, Lessingstraße 12, D-07743 Jena, Germany.

The decomposition of chloroform by the combination of hydrodynamic and acoustic cavitation (Hydrodynamic-Acoustic-Cavitation/HAC) has been investigated. The flow rate and the hole diameter of the orifice plate remarkably affect the conversion of chloroform in the combined system. The conversion increases with increasing fluid velocity without any restriction. With a 2.8mm orifice plate the conversion reaches an optimal value. A synergistic effect has been obtained by the hybrid method of acoustic and hydrodynamic cavitation. The total synergistic effect achieves 17% and 73% per pass, respectively. The analysis of the energy efficiencies shows different results. Due to high optimization potential, this hybrid method can be visualized as a new step for wastewater treatment.
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http://dx.doi.org/10.1016/j.ultsonch.2010.11.011DOI Listing
July 2011

[Microbial biomass and activity in a full-scale O3-BAC filter].

Huan Jing Ke Xue 2010 May;31(5):1211-4

College of Environmental science and Engineering, Hohai University, Nanjing 210098, China.

The microbial biomass and activity in a full-scale drinking water O-BAC filter was investigated using the methods of lipid-P and SOUR. Because of the effect of O3 residue on TOC distribution and the formation of biofilm in biofilters could be inhibited by O3 residue in influent, the biomass in filter showed an "increase-reduce" pattern along vertical section and had a peak at the depth of 10 em. The SOUR per unit biomass fluctuated at the magnitude of 10(-4) mg/(nmol x h) with an adverse distribution to the biomass itself. The SOUR per unit volume media was around 10(-2) mg/(cm3 x h) and presented same tendency with biomass distribution at the media depth of 0-20 cm. The deeper distribution of SOURs per unit volume media had the same tendency with SOURs per unit biomass. All biomass demonstrated a certain increase of activity potential and the biomass attached to deeper media had a higher increase, which suggested the increase of metabolic activity provided a possible pathway for resistance of the reactors to shock load.
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May 2010

Oxidative degradation of chlorophenol derivatives promoted by microwaves or power ultrasound: a mechanism investigation.

Environ Sci Pollut Res Int 2010 Mar 9;17(3):674-87. Epub 2009 Oct 9.

Dipartimento di Scienza e Tecnologia del Farmaco, University of Turin, 10125, Turin, Italy.

Background, Aim, And Scope: Phenols are the most common pollutants in industrial wastewaters (particularly from oil refineries, resin manufacture, and coal processing). In the last two decades, it has become common knowledge that they can be effectively destroyed by nonconventional techniques such as power ultrasound (US) and/or microwave (MW) irradiation. Both techniques may strongly promote advanced oxidation processes (AOPs). The present study aimed to shed light on the effect and mechanism of US- and MW-promoted oxidative degradation of chlorophenols; 2,4-dichlorophenoxyacetic acid (2,4-D), a pesticide widespread in the environment, was chosen as the model compound.

Materials And Methods: 2,4-D degradation by AOPs was carried out either under US (20 and 300 kHz) in aqueous solutions (with and without the addition of Fenton reagent) or solvent-free under MW with sodium percarbonate (SPC). All these reactions were monitored by gas chromatography-mass spectrometry (GC-MS) analysis and compared with the classical Fenton reaction in water under magnetic stirring. The same set of treatments was also applied to 2,4-dichlorophenol (2,4-DCP) and phenol, the first two products that occur a step down in the degradation sequence. Fenton and Fenton-like reagents were employed at the lowest active concentration.

Results: The effects of US and MW irradiation were investigated and compared with those of conventional treatments. Detailed mechanisms of Fenton-type reactions were suggested for 2,4-D, 2,4-DCP, and phenol, underlining the principal degradation products identified. MW-promoted degradation under solvent-free conditions with solid Fenton-like reagents (viz. SPC) is extremely efficient and mainly follows pyrolytic pathways. Power US strongly accelerates the degradation of 2,4-D in water through a rapid generation of highly reactive radicals; it does not lead to the formation of more toxic dimers.

Discussion: We show that US and MW enhance the oxidative degradation of 2,4-D and that a considerable saving of oxidants and cutting down of reaction times is thereby achieved. The results support the interpretation of previously published data and improve the understanding of the factors of direct degradation along different pathways.

Conclusions: Oxidative pathways for 2,4-D, 2,4-DCP, and phenol were proposed by a careful monitoring of the reactions and detection of intermediates by GC-MS.

Recommendations And Perspectives: The understanding of the factors that affect chlorophenols degradation along different pathways may facilitate the optimization of the treatment. Type of energy source (US or MW), power, and frequency to be applied could be designed in function of the operative scenario (amount of pollutant in soil, water, or oils).
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http://dx.doi.org/10.1007/s11356-009-0253-yDOI Listing
March 2010

Degradation of phenol under combined irradiation of microwaves and ultrasound.

Environ Sci Technol 2008 Nov;42(21):8083-7

Institute of Technical Chemistry and Environmental Chemistry, Friedrich Schiller University Jena, Lessingstrasse 12, 07743 Jena, Germany.

A novel combined system of irradiation by microwaves and ultrasound is used to efficiently destroy phenol in aqueous solutions via sono-generated hydroxyl radicals and H2O2, in conjunction with the rapid thermal effect of microwaves on polar chemicals. Microwave irradiation enhances the sono-degradation of phenol without any additional catalyst although the effect is more marked when H2O2 is added. The degradation of phenol by MW or US alone or by combined irradiation of MW-US follows zero order kinetics. Degradation rate constants and yields of the main intermediates, catechol and hydroquinone, follow the order of MW-US > MW > US. The degradation rate also increases with higher reaction temperature in the MW reactor. The synergistic effects of MW and US were observed at 93 degrees C without addition of H2O2 and at 60 degrees C with addition of H2O2.
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http://dx.doi.org/10.1021/es8013375DOI Listing
November 2008