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1.
J Environ Manage ; 329: 117072, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36584516

RESUMEN

Safe and green disposal or utilization of sewage sludge (SS) has attracted significant attention as SS is increasingly produced worldwide and emerges as an environmental burden if without proper treatment. In this study, efficient and sustainable treatment of SS was achieved using plasma-electrolytic liquefaction (PEL) with alkaline catalysts including sodium hydroxide (NaOH), sodium carbonate (Na2CO3), and sodium acetate (NaAc) and renewable solvents including polyethylene glycol (PEG) 200 and glycerol. Furthermore, the obtained bio-oil with abundant hydroxyl groups could partially replace polyols derived from fossil energy to synthesize bio-based polyurethane foams (BPUFs) for oil adsorption. The results showed that the Na2CO3 catalyst exhibited better performance and yielded bio-oil with a higher heating value (HHV) of 26.26 MJ/kg, very low nitrogen content (0.14%) and metal ions, and a nearly neutral pH of 7.41, under the optimized conditions. Compared with conventional oil bath liquefaction, PEL can significantly improve the liquefaction efficiency, promote the transfer of metal ions in SS to the solid residue (SR), and facilitate the transfer of nitrogen to the gas phase and SR, thereby upgrading the bio-oil to a certain extent. The BPUFs showed excellent oil adsorption capacity, reusability, and desorption and can play an important role in combating oil spills. The PEL method may provide a green avenue for SS valorization and the comprehensive utilization of the obtained products.


Asunto(s)
Poliuretanos , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Biocombustibles , Iones , Metales/análisis , Poliuretanos/química , Aguas del Alcantarillado/química , Temperatura , Eliminación de Residuos Líquidos/métodos
2.
Chemosphere ; 292: 133454, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34971629

RESUMEN

This study used acetone washing biochar (BCA) and nitric-acid washing biochar (BCN) derived from bagasse to remove sulfamethoxazole (SMX) and tetracycline (TC) in water. Higher specific surface area (1119.53 m2 g-1) and graphitization degree can significantly improve decontamination efficacy, of which BCN has the highest SMX and TC sorption capacities (274.63 mg g-1 and 353.85 mg g-1). The kinetics, isotherms and characterization analysis indicated O-containing functional group complexation and π-π interaction were dominant mechanisms in the adsorption process. Adsorption stability experiment showed that BCA has better stability with the coexistence of anions and cations. Besides, the enhancement and competitive adsorption from the interaction between soluble organic matter and TC could facilitate TC decontamination. Therefore, bagasse biochar derived from agro-waste has a promising potential for antibiotic contaminants removal from multi-interference conditions and promotes the recycling of waste, thereby achieving harmony between materials and the ecological environment.


Asunto(s)
Pirólisis , Contaminantes Químicos del Agua , Adsorción , Antibacterianos , Carbón Orgánico , Cinética , Contaminantes Químicos del Agua/análisis
3.
J Org Chem ; 86(18): 13092-13099, 2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34470208

RESUMEN

We developed the radical cyclization/addition of alkynylphosphine oxides with easily available cycloalkanes, alcohols, and ethers using a visible-light and environmentally friendly synthetic strategy in the absence of photocatalyst at room temperature. This mild and metal- and base-free reaction provided a structurally varied set of significant benzo[b]phosphole oxides through sequential C-H functionalization in an atom-economical manner.

4.
J Org Chem ; 85(10): 6359-6371, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32299209

RESUMEN

The first metal-free and facile radical addition/cyclization of simple alcohols with diaryl(arylethynyl)phosphine oxides has been described with azobisisobutyronitrile as a radical initiator, affording an efficient and one-pot procedure to access a new class of hydroxymethyl benzo[b]phosphole oxides and 6H-indeno[2,1-b]phosphindole 5-oxides for potential application in organic materials via sequential C(sp3)-H/C(sp2)-H functionalization. The method employs easily accessible starting materials and is endowed with high regioselectivity and broad functional-group tolerance.

5.
Bioresour Technol ; 241: 545-551, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28601772

RESUMEN

In this work, plasma electrolytic technology was successfully employed to achieve fast liquefaction of sawdust when polyethylene glycol 200 (PEG 200) and glycerol were used as liquefacient in the presence of the catalyst sulfuric acid. Results showed that H ions could heat the solution effectively during the plasma electrolytic liquefaction (PEL) process. The influence of some key parameters including liquefaction time, catalyst percentage, liquefacient/sawdust mass ratio, and PEG 200/glycerol molar ratio on the liquefaction yield were investigated. Based on the results of single factor experiments, response surface methodology (RSM) was applied to optimize the liquefaction process. Under the optimal conditions that is liquefaction time of 5.10min, catalyst percentage of 1.05%, liquefacient/sawdust mass ratio of 7.12/1 and PEG 200/glycerol molar ratio of 1.40/1, the liquefaction yield reached 99.48%. Hence, it could be concluded that PEL has good application potential for biomass fast liquefaction.


Asunto(s)
Polietilenglicoles , Madera , Biomasa , Catálisis , Glicerol
6.
Bioresour Technol ; 218: 1275-8, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27426102

RESUMEN

In this study, liquid-phase microplasma technology (LPMPT) was employed to facilitate the liquefaction of bamboo shoot shell (BSS) in polyethylene glycol 400 (PEG 400) and ethylene glycol (EG) mixture. Effects of liquefaction conditions such as liquefaction time, catalyst percentage, solvent/BSS mass ratio, PEG/EG volume ratio on liquefaction were investigated experimentally. The results showed that the introduction of LPMPT significantly shortened the liquefaction time to 3min without extra heating. The liquefaction yield reached 96.73% under the optimal conditions. The formation of massive reactive species and instantaneous heat accumulation both contributed to the rapid liquefaction of BSS. Thus, LPMPT could be considered as a simple and efficient method for the assistance of biomass fast liquefaction.


Asunto(s)
Biomasa , Biotecnología/métodos , Sasa/química , Calor , Polietilenglicoles , Solventes
7.
Chem Biol Drug Des ; 85(6): 743-55, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25346294

RESUMEN

Twenty-one novel oxime ether strobilurins containing indole moiety, which employed an indole group to stabilize the E-styryl group in Enoxastrobin, were designed and synthesized. The biological assay indicated that most compounds exhibited potent fungicidal activities. The structure-activity relationship study demonstrated that the synthesized methyl 3-methoxypropenoate oxime ethers 7b-e exhibited remarkably high activities among all the synthesized oxime ether compounds 7. Moreover, the fungicidal activities of methyl α-(methoxyimino)benzeneacetate oxime ethers compounds 7f-i and N-methoxy-carbamic acid methyl esters compounds 7j-m showed significant differences compared to the corresponding products of ammonolysis.


Asunto(s)
Hongos/efectos de los fármacos , Fungicidas Industriales/química , Indoles/química , Oximas/química , Éteres/síntesis química , Éteres/química , Éteres/farmacología , Ácidos Grasos Insaturados/síntesis química , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Fungicidas Industriales/síntesis química , Fungicidas Industriales/farmacología , Indoles/síntesis química , Indoles/farmacología , Metacrilatos/síntesis química , Metacrilatos/química , Metacrilatos/farmacología , Oximas/síntesis química , Oximas/farmacología , Estrobilurinas , Relación Estructura-Actividad
8.
Pest Manag Sci ; 71(3): 404-14, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24777582

RESUMEN

BACKGROUND: Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin analogues with broad spectrum and high activity, a series of novel oxime ether strobilurin derivatives containing substituted benzofurans in the side chain were synthesised and bioassayed. RESULTS: The synthesised compounds were characterised by (1) H NMR, (13) C NMR, MS and HRMS. Bioassays demonstrated that most target compounds possessed good or excellent fungicidal activities, especially against Erysiphe graminis and Pyricularia oryzae. Furthermore, methyl 3-methoxypropenoate oxime ethers exhibited remarkably higher activities against E. graminis, Colletotrichum lagenarium and Puccinia sorghi Schw. Notably, (E,E)-methyl 3-methoxy-2-{2-[({[5-fluoro-1-(benzofuran-2-yl)ethylidene]amino}oxy)methyl]phenyl}propenoate (BSF2) and (E,E)-methyl 3-methoxy-2-{2-[({[5-chloro-1-(benzofuran-2-yl)ethylidene]amino}oxy)methyl]phenyl}propenoate (BSF3) were identified as the most promising candidates for further study. CONCLUSION: The present work demonstrates that oxime ether strobilurin derivatives containing benzofurans can be used as possible lead compounds for developing novel fungicides.


Asunto(s)
Hongos/efectos de los fármacos , Fungicidas Industriales/química , Fungicidas Industriales/síntesis química , Ácidos Grasos Insaturados/síntesis química , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Fungicidas Industriales/farmacología , Espectroscopía de Resonancia Magnética , Metacrilatos/síntesis química , Metacrilatos/química , Metacrilatos/farmacología , Oximas/síntesis química , Oximas/química , Oximas/farmacología , Relación Estructura-Actividad
9.
Bioorg Med Chem Lett ; 24(9): 2173-6, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24717155

RESUMEN

Twenty-one novel benzothiophene-substituted oxime ether strobilurins, which employed a benzothiophene group to stabilise the E-styryl group in Enoxastrobin (an unsaturated oxime strobilurin fungicide developed by Shenyang Research Institute of Chemical Industry, China) were designed and synthesised. The biological assay indicated that most compounds exhibited good or excellent fungicidal activities, especially against Colletotrichum lagenarium and Puccinia sorghi Schw. In addition, methyl 3-methoxypropenoate oxime ethers and N-methoxy-carbamic acid methyl esters exhibited good in vivo fungicidal activities against Erysiphe graminis, Colletotrichum lagenarium and Puccinia sorghi Schw. under the tested concentrations. Notably, (E,E)-methyl 3-methoxy-2-(2-((((6-chloro-1-(1H-benzo[b]thien-2-yl)ethylidene)amino)oxy)methyl)phenyl)propenoate (5E) exhibited more potent in vivo fungicidal activities against nearly all of the tested fungi at a concentration of 0.39 mg/L compared to Enoxastrobin.


Asunto(s)
Hongos/efectos de los fármacos , Fungicidas Industriales/química , Fungicidas Industriales/toxicidad , Tiofenos/química , Tiofenos/toxicidad , Ácidos Grasos Insaturados/síntesis química , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/toxicidad , Fungicidas Industriales/síntesis química , Metacrilatos/síntesis química , Metacrilatos/química , Metacrilatos/toxicidad , Oximas/síntesis química , Oximas/química , Oximas/toxicidad , Estrobilurinas , Tiofenos/síntesis química
10.
Bioresour Technol ; 153: 147-53, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24361486

RESUMEN

Bamboo (Dendrocalamus latiflorus Munro) shoot shell (BSS) was liquefied in polyethylene glycol 400 (PEG400) and ethylene glycol (EG) catalyzed by sulfuric acid under atmospheric pressure. The effects of liquefaction conditions such as liquid-solid ratio, temperature, time, catalyst, solvents ratio, and material size on the liquefaction yield of BSS have been investigated. Methods including Elemental analysis, Thermogravimetric analysis, Fourier transform infrared spectroscopy, nuclear magnetic resonance and gas chromatography-mass spectrometry were selected to analyze the characteristics of products in three fractions: an aqueous fraction (AQ), an acetone-soluble fraction (AS) and a residue (RS), respectively. Results showed that the highest liquefaction percentage was 99.79% under the optimal conditions (liquid-solid ratio 6:1; temperature 150°C; reaction time 80min; raw size more than 40 mesh; catalyst mass percentage of solvent 4%; solvent volume ratio 3:1). Polyols could be obtained effectively by the liquefaction of BSS, an agricultural by-product.


Asunto(s)
Bambusa/química , Biotecnología/métodos , Brotes de la Planta/química , Polímeros/metabolismo , Acetona/química , Catálisis , Fraccionamiento Químico , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Solubilidad , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termogravimetría , Factores de Tiempo
11.
J Nat Prod ; 75(10): 1810-3, 2012 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-23075087

RESUMEN

The roots of Polygonum cuspidatum produce several phenolic compounds, including trans-resveratrol (1), trans-piceid (2), and emodin (3), and are a commercial source of the botanical dietary supplement 1. Ultrasonic-assisted extraction technology and conventional shaking extraction procedures were compared for the extraction of 1-3 from P. cuspidatum roots, using 50% ethanol as a food grade solvent. These compounds were extracted successfully, and their mass transfer coefficients were calculated by fitting the experimental results to a model derived from Fick's second law. The results indicated that ultrasonic-assisted extraction had higher mass transfer efficacies and extraction yields for 1-3 as compared with conventional shaking extraction. Under the extraction conditions used (extraction temperature 50 °C; ultrasonic power 150 W), yields of 3.5, 9.2, and 7.8 mg/g were obtained for 1-3, respectively.


Asunto(s)
Fallopia japonica/química , Estilbenos/química , Estilbenos/farmacología , Ultrasonido/métodos , Suplementos Dietéticos , Espectroscopía de Resonancia por Spin del Electrón , Modelos Químicos , Estructura Molecular , Raíces de Plantas/química , Resveratrol , Estereoisomerismo , Estilbenos/aislamiento & purificación , Taiwán
12.
J Agric Food Chem ; 56(13): 5247-53, 2008 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-18547049

RESUMEN

Nineteen novel indene-substituted oxime ether strobilurins, which used an indene group to stabilize the ( E)-styryl group in SYP-Z071 (an unsaturated oxime strobilurin fungicide under development by the Shenyang Research Institute of Chemical Industry), were designed and synthesized. The biological assay results showed that all compounds possessed good or excellent fungicidal activities. It was found that most of the compounds showed higher fungicidal activities against Pyricularia oryzae, Phytophthora infestans, Erysiphe graminis, and Colletotrichum lagenarium than SYP-Z071 at the tested concentration. The biological assay results also indicated that most of the compounds exhibited higher in vivo fungicidal activities against cucumber Pseudoperonospora cubensis and C. lagenarium than the commercial fungicides trifloxystrobin and kresoxim-methyl at a concentration of 6.25 mg/L. Furthermore, it was found that alpha-(methoxyimino)- N-methylphenylacetamide oxime ethers 6m- s exhibited a broad spectrum and remarkably higher activities against all tested fungi. Especially, the 6-methylindene-substituted compound 6p was identified as the most promising candidate for further study.


Asunto(s)
Acrilatos/síntesis química , Acrilatos/farmacología , Hongos/efectos de los fármacos , Fungicidas Industriales/síntesis química , Fungicidas Industriales/farmacología , Acrilatos/química , Éteres , Fungicidas Industriales/química , Indenos/síntesis química , Indenos/química , Indenos/farmacología , Estructura Molecular , Oximas/síntesis química , Oximas/química , Oximas/farmacología , Relación Estructura-Actividad
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