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1.
Sci Total Environ ; 820: 153083, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35033567

RESUMO

The effects of lignin (LIG) on coal gangue (CG) pyrolysis characteristics, gas emissions, and multi-lump parallel reaction modeling are studied in this paper. The combined thermogravimetry and Fourier infrared spectrometer were used to obtain the weight loss and gas product functional group data of the co-pyrolysis of coal gangue and lignin. Gaussian peaks were used to analyze the reaction degree of different proportions of lignin added to coal gangue at different temperatures. Moreover, principal component analysis (PCA) is applied to further analyze pyrolysis reaction process. During the pyrolysis of C1L3 samples, a synergistic interaction was discovered. The optimal mixing ratio of coal gangue and lignin during pyrolysis was obtained. The influence mechanism of lignin on coal gangue pyrolysis is studied in this article, which can provide technical support for the reduction and resource utilization of coal gangue. There are six-lump parallel reactions in pyrolysis after CG and LIG are mixed. The addition of LIG changed the CO2 release law of CG pyrolysis. The strengthening of coal gangue disposal research is of positive significance for improving the environment and increasing the utilization rate of coal.

2.
Sci Total Environ ; 804: 150217, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34520910

RESUMO

Co-pyrolysis technology of urban solid waste and biomass has broad application prospects in alleviating energy crisis and environmental pollution. In this study, thermogravimetric-Fourier transform infrared spectroscopy (TG-FTIR) was used to study the co-pyrolysis characteristics of coal gangue (CG) and coffee industry residue (CIR). CG and CIR were uniformly mixed according to the mass ratios of 1: 0, 7:3, 5:5, 3:7, and 0:1. Then the samples were heated and pyrolyzed in an atmosphere with a nitrogen flow rate of 60 mL/min. As the proportion of CG increased, the comprehensive pyrolysis index (CPI) showed an exponential decrease. FTIR detected that the gas produced by pyrolysis of CG-CIR contained hydroxyl compounds, hydrocarbons, CO2, CO, Phenols, and NH3. CG-CIR co-pyrolysis had obvious interaction. By using Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods, the relationship between activation energy (Eα) and kinetic parameters and conversion degree was studied. Principal component analysis (PCA) was used to determine the principal reaction of CG-CIR pyrolysis. ANN 21 was the best model for predicting the pyrolysis of CG-CIR.


Assuntos
Carvão Mineral , Pirólise , Biomassa , Carvão Mineral/análise , Café , Cinética , Idioma , Termodinâmica , Termogravimetria
3.
Sci Total Environ ; 798: 149290, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340093

RESUMO

The pyrolysis experiment of biomass added to coal gangue was studied by thermogravimetric-Fourier transform infrared spectroscopy-mass spectrometry (TG-FTIR-MS) method. The multi-component reaction model was used to simulate the pyrolysis reaction of coal gangue and biomass. The most suitable model was obtained, and the pyrolysis mechanism was analyzed. According to the two-component reaction model of CG pyrolysis, the decomposition temperature range of components in CG is 340-800 °C and 400-620 °C. The five-component reaction model can well simulate the pyrolysis process of coal gangue and biomass. Meanwhile, the effects of different proportions of biomass in the mixture on the gas products of coal gangue pyrolysis were analyzed. It was found that the addition of biomass to coal gangue could promote the release of gaseous organic matter during pyrolysis. CG75PS25 only has a synergistic effect in the high temperature zone greater than 600 °C. CG25PS75 only has a synergistic effect in a small range of 230-300 °C, and there is an inhibitory effect in other temperature ranges. In general, there is an inhibitory effect between coal gangue and biomass on CO2 formation, which is of positive significance for greenhouse gas emission reduction.


Assuntos
Carvão Mineral , Pirólise , Biomassa , Carvão Mineral/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
4.
Zhongguo Zhong Yao Za Zhi ; 42(8): 1439-1448, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29071845

RESUMO

Urinary tract infection (UTI) in traditional Chinese medicine (TCM) belongs to the category of stranguria. This article describes the unsatisfactory situations in clinical practice such as antibiotics abuse, increasing of drug-resistant bacteria, high recurrence rate, etc. According to evidence-based medicine, literatures as evidence are collected for summarizing and analyzing and the result shows the advantages of TCM of relieving symptoms, reducing the dosage of antibiotics, less side effects, lower recurrence rate, etc. In the field of fundamental research, literatures associated with UTI are also summarized and analysed from several perspectives, such as causes, pathogenesis, syndrome differentiation, pharmacological effects of Chinese herbal medicine, working mechanism of non-drug therapy, etc and the result presents that integrated treatment of TCM in UTI has significant advangtages and its own characteristic.


Assuntos
Medicina Tradicional Chinesa , Infecções Urinárias/prevenção & controle , Infecções Urinárias/terapia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Baseada em Evidências , Humanos
5.
Arch Environ Contam Toxicol ; 63(1): 22-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22203462

RESUMO

Low molecular-mass nonylphenol ethoxylates (NPEOs) and 4-nonylphenol (NP) are biodegradation products of higher molecular mass NPEOs used as surface active agents, and they are endocrine-disrupting contaminants. In this study, surface soil (0-20 cm) samples and different vegetable samples were collected from 27 representative vegetable farms located in Shenzhen, Dongguan, and Huizhou within the Pearl River Delta region, South China, and NP and nonylphenol monoethoxylate (NP(1)EO) were analyzed using high-performance liquid chromatography with ultraviolet detection. The results show that NP and NP(1)EO were detected in soil and vegetable samples. The concentrations of NP and NP(1)EO in soil samples ranged from nondetectable (ND) to 7.22 µg kg(-1) dry weight (dw) and from ND to 8.24 µg kg(-1) dw, respectively. The average concentrations of both NP and NP(1)EO in soil samples decreased in the following order: Dongguan > Huizhou > Shenzhen. The levels of NP and NP(1)EO in vegetable samples varied from 1.11 to 4.73 µg kg(-1) dw and from 1.32 to 5.33 µg kg(-1) dw, respectively. The greatest levels of both NP and NP(1)EO were observed in water spinach, and the lowest levels of NP and NP(1)EO were recorded in cowpea. The bioconcentration factors (the ratio of contaminant concentration in plant tissue to soil concentration) of NP and NP(1)EO were <1.0 (mean 0.535 and 0.550, respectively). The occurrences of NP and NP(1)EO in this study are compared with other studies, and their potential sources are discussed.


Assuntos
Monitoramento Ambiental/métodos , Etilenoglicóis/análise , Fenóis/análise , Poluentes Químicos da Água/análise , China , Cromatografia Líquida de Alta Pressão/métodos , Controle de Qualidade , Poluentes do Solo/análise , Tensoativos/análise , Verduras/química
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