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1.
Molecules ; 29(9)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38731644

RESUMEN

A novel pretreatment strategy utilizing a combination of NaOH and 1-Butyl-3-methylimidazolium chloride ([Bmim]Cl) was proposed to enhance the enzymatic hydrolysis of abandoned Medium-density fiberboard (MDF). The synergistic effect of NaOH and [Bmim]Cl pretreatment significantly improved the glucose yield, reaching 445.8 mg/g within 72 h, which was 5.04 times higher than that of the untreated samples. The working mechanism was elucidated according to chemical composition, as well as FTIR, 13C NMR, XRD, and SEM analyses. The combined effects of NaOH and [Bmim]Cl led to lignin degradation, hemicellulose removal, the destruction and erosion of crystalline regions, pores, and an irregular microscopic morphology. In addition, by comparing the enzymatic hydrolysis sugar yield and elemental nitrogen content of untreated MDF samples, eucalyptus, and hot mill fibers (HMF), it was demonstrated that the presence of adhesives and additives in waste MDF significantly influences its hydrolysis process. The sugar yield of untreated MDF samples (88.5 mg/g) was compared with those subjected to hydrothermal pretreatment (183.2 mg/g), Ionic liquid (IL) pretreatment (406.1 mg/g), and microwave-assisted ionic liquid pretreatment (MWI) (281.3 mg/g). A long water bath pretreatment can reduce the effect of adhesives and additives on the enzymatic hydrolysis of waste MDF. The sugar yield produced by the combined pretreatment proposed in this study and the removal ability of adhesives and additives highlight the great potential of our pretreatment technology in the recycling of waste fiberboard.

2.
J Neurointerv Surg ; 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37438103

RESUMEN

BACKGROUND: Clip ligation of anterior cranial fossa (ACF) dural arteriovenous fistulas (DAVFs) is the traditionally accepted first-line treatment. Endovascular treatment for ACF DAVFs may achieve good outcomes as endovascular techniques advance. Here we report the clinical and angiographic outcomes in patients with ACF DAVFs who underwent transarterial embolization (TAE) as first-line treatment. METHODS: Over a 20-year period, 87.0% (40/46) of patients received TAE as first-line treatment. The clinical presentation, angiographic features, treatment strategy, and clinical and angiographic outcomes are described in this article. RESULTS: Forty patients underwent TAE as first-line treatment. There were 36 men and 4 women, with a mean age of 55.6 (55.6±7.4) years. A total of 64 embolization attempts were performed. The middle meningeal artery (66.7%, 12/18) and the ophthalmic artery (54.2%, 13/24) were the most frequently used arterial access routes for complete embolization. The second option was the sphenopalatine artery (46.7%, 7/15). Complications, that is, retinal ischemia, occurred in one patient (2.5%). The total immediate complete occlusion rate for TAE was 82.5% (33/40). Two patients needed surgery for incomplete embolization. When followed up (90%, 36/40), one patient (2.8%, 1/36) reported worsening symptoms due to retinal ischemia following TAE. Although fewer than 50% of the patients received digital subtraction angiography follow-up, there were no recurrences. CONCLUSIONS: We show that TAE is safe and effective in the treatment of ACF DAVFs in this study of 40 patients, making it a viable alternative to surgical ligation and transvenous embolization. More research is needed to compare these various treatment modalities.

5.
J Bioenerg Biomembr ; 55(1): 43-57, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36807837

RESUMEN

BACKGROUND: Mitochondria are remarkably dynamic organelles encapsulated by bilayer membranes. The dynamic properties of mitochondria are critical for energy production. AIMS: The aim of our study is to investigate the global status and trends of mitochondrial dynamics research and predict popular topics and directions in the field. METHODS: Publications related to the studies of mitochondrial dynamics from 2002 to 2021 were retrieved from Web of Science database. A total of 4,576 publications were included. Bibliometric analysis was conducted by visualization of similarities viewer and GraphPadPrism 5 software. RESULTS: There is an increasing trend of mitochondrial dynamics research during the last 20 years. The cumulative number of publications about mitochondrial dynamics research followed the logistic growth model [Formula: see text]. The USA made the highest contributions to the global research. The journal Biochimica et Biophysica Acta (BBA)-Molecular Cell Research had the largest publication numbers. Case Western Reserve University is the most contributive institution. The main research orientation and funding agency were cell biology and HHS. All keywords related studies could be divided into three clusters: "Related disease research", "Mechanism research" and "Cell metabolism research". CONCLUSIONS: Attention should be drawn to the latest popular research and more efforts will be put into mechanistic research, which may inspire new clinical treatments for the associated diseases.


Asunto(s)
Dinámicas Mitocondriales , Programas Informáticos , Humanos , Bibliometría
6.
BMC Musculoskelet Disord ; 23(1): 986, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36380305

RESUMEN

BACKGROUND: Various authors have successfully demonstrated that the distance from the greater trochanter to the femoral head center (GTFHC) and the distance from the lesser trochanter to the femoral head center (LTFHC) can be used as parameters to determine the recovery of the femoral head center (FHC) during hip arthroplasty. It is necessary to undertake an anatomical study concerning the correlations between the greater trochanter (GT), the lesser trochanter (LT), and the FHC using data obtained from the 3D-CT reconstruction method. METHODS: The study comprised 293 patients (151 males and 142 females), with an average age of 65.06 years. The femoral head diameter(FHD), the linear distance from FHC to GT (GTFHC), and the linear distance from FHC to LT(LTFHC) were all measured and recorded data. The correlation between FHD with LTFHC and GTFHC was assessed using Pearson correlation coefficients, and the ratio of LTFHC and GTFHC to FHD was calculated from this ratio. All measured parameters were compared between the left and right sides and the sexes of the participants. RESULTS: The average ratios of GTFHC/FHD and LTFHC/FHD were 0.99 and 0.95, respectively .96% of the LTFHC had absolute lateral differences of < 4 mm . 92% of the GTFHC had absolute lateral differences of < 4 mm. CONCLUSION: LTFHC and GTFHC are reliable reference parameters for preoperative planning and reconstruction of FHC of hip arthroplasty. The ratio displayed in this research may yield insight into a practical and straightforward method for orthopedic surgeons to perform hip arthroplasty in patients with femoral neck fractures. Ratios from studies based on the same race may be desirable for future work.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Fracturas del Cuello Femoral , Masculino , Femenino , Humanos , Anciano , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/cirugía , Fémur/cirugía , Fracturas del Cuello Femoral/cirugía , China
7.
Molecules ; 27(22)2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36431979

RESUMEN

In this study, a two-step method was used to realize the liquefaction of waste sawdust under atmospheric pressure, and to achieve a high liquefaction rate. Specifically, waste sawdust was pretreated with NaOH, followed by liquefaction using phenol. The relative optimum condition for alkali-heat pretreatment was a 1:1 mass ratio of NaOH to sawdust at 140 °C. The reaction parameters including the mass ratio of phenol to pretreated sawdust, liquefaction temperature, and liquefaction time were optimized by response surface methodology. The optimal conditions for phenol liquefaction of pretreated sawdust were a 4.21 mass ratio of phenol to sawdust, a liquefaction temperature of 173.58 °C, and a liquefaction time of 2.24 h, resulting in corresponding liquefied residues of 6.35%. The liquefaction rate reached 93.65%. Finally, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) were used to analyze untreated waste sawdust, pretreated sawdust, liquefied residues, and liquefied liquid. SEM results showed that the alkali-heat pretreatment and liquefaction reactions destroyed the intact, dense, and homogeneous sample structures. FT-IR results showed that liquefied residues contain aromatic compounds with different substituents, including mainly lignin and its derivatives, while the liquefied liquid contains a large number of aromatic phenolic compounds. XRD showed that alkali-heat pretreatment and phenol liquefaction destroyed most of the crystalline regions, greatly reduced the crystallinity and changed the crystal type of cellulose in the sawdust.


Asunto(s)
Fenol , Fenoles , Hidróxido de Sodio , Espectroscopía Infrarroja por Transformada de Fourier , Álcalis
8.
Front Oncol ; 12: 980620, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36158661

RESUMEN

It is widely thought that the tumor microenvironment (TME) provides the "soil" for malignant tumors to survive. Prior to metastasis, the interaction at the host site between factors secreted by primary tumors, bone-marrow-derived cells, with stromal components initiates and establishes a pre-metastatic niche (PMN) characterized by immunosuppression, inflammation, angiogenesis and vascular permeability, as well as lymphangiogenesis, reprogramming and organotropism. Ferroptosis is a non-apoptotic cell death characterized by iron-dependent lipid peroxidation and metabolic constraints. Ferroptotic cancer cells release various signal molecules into the TME to either suppress or promote tumor progression. This review highlights the important role played by ferroptosis in PMN, focusing on the relationship between ferroptosis and PMN characteristics, and discusses future research directions.

9.
Front Mol Biosci ; 9: 974156, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36060242

RESUMEN

Glioblastoma (GBM) is the most common malignant craniocerebral tumor. The treatment of this cancer is difficult due to its high heterogeneity and immunosuppressive microenvironment. Ferroptosis is a newly found non-apoptotic regulatory cell death process that plays a vital role in a variety of brain diseases, including cerebral hemorrhage, neurodegenerative diseases, and primary or metastatic brain tumors. Recent studies have shown that targeting ferroptosis can be an effective strategy to overcome resistance to tumor therapy and immune escape mechanisms. This suggests that combining ferroptosis-based therapies with other treatments may be an effective strategy to improve the treatment of GBM. Here, we critically reviewed existing studies on the effect of ferroptosis on GBM therapies such as chemotherapy, radiotherapy, immunotherapy, and targeted therapy. In particular, this review discussed the potential of ferroptosis inducers to reverse drug resistance and enhance the sensitivity of conventional cancer therapy in combination with ferroptosis. Finally, we highlighted the therapeutic opportunities and challenges facing the clinical application of ferroptosis-based therapies in GBM. The data generated here provide new insights and directions for future research on the significance of ferroptosis-based therapies in GBM.

10.
Knee ; 29: 510-519, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33756261

RESUMEN

BACKGROUND: The systems for precisely locating the joint line during primary and revision total knee arthroplasty are still controversial, and they should be better evaluated in the Chinese population. METHODS: A total of 451 standard anteroposterior knee radiographs from 451 healthy Chinese people (283 males and 168 females, the average age of 33.26 years, range 20-50 years) were included to measure the femoral width (FW) and the distances from the adductor tubercle (AT), the medial epicondyle (ME), the lateral epicondyle (LE), and the fibular head (FH) to the joint line (JL). Correlation between FW and distances from landmarks to the joint line was evaluated using Pearson correlation coefficient, and the ratios of ATJL, MEJL, LEJL, FHJL to FW were calculated. RESULTS: The average distances from the AT, the ME, the LE, the FH to the JL were 49.4 ± 5.0 mm, 28.3 ± 3.1 mm, 26.9 ± 2.9 mm, 20.0 ± 4.0 mm, respectively. An excellent linear correlation was found between FW and the distance from AT to the joint line (R = 0.836, R2 = 0.698); it was more reliable than the LE (R = 0.686, R2 = 0.471) and the ME (R = 0.672, R2 = 0.452). The average ratios of ATJL/FW, MEJL/FW, LEJL/FW were 0.553, 0.317, and 0.302, respectively. There were significant differences between our results and the studies based on the Western people. CONCLUSION: The AT can be used as a reliable landmark to locate the JL precisely by the formula (ATJL = 0.548 × FW in males; ATJL = 0.562 × FW in females) in the Chinese population. The LE and ME can be the second choices. Moreover, it may be better to use ratios from the research based on the same race.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Fémur/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Adulto , Artroplastia de Reemplazo de Rodilla/efectos adversos , Pueblo Asiatico , Femenino , Fémur/cirugía , Peroné/diagnóstico por imagen , Peroné/cirugía , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reoperación , Adulto Joven
11.
Sci Rep ; 11(1): 1262, 2021 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-33441699

RESUMEN

Febrile seizures (FSs) are common neurological disorders in both infants and children, although the precise underlying mechanism remains to be explored, especially in the expression pattern and function of microRNAs (miRNAs). In this report, we aimed to screen new potential miRNAs and examine the role of miR-148a-3p in hippocampal neurons in FS rats via Synaptojanin-1 (SYNJ1). Thirty rats were randomly divided into the normal and FS model groups, which were investigated by miRNA array. This process identified 31 differentially expressed (20 upregulated and 11 downregulated) miRNAs and potential miRNA target genes. In addition, hippocampal neurons were assigned into five groups for different transfections. Apoptosis was detected by TUNEL and flow cytometry. SYNJ1 was identified as a target gene of miR-148-3p. In vitro experiments revealed that inhibition of miR-148a-3p decreased neuronal cell apoptosis. Moreover, overexpression of miR-148a-3p resulted in activation of PI3K/Akt signaling pathway and the apoptosis of hippocampal neurons. MiR-148a-3p inhibitor could reverse the above events. Taken together, our data demonstrated that the hippocampal miRNA expression profiles of a rat model of FS provide a large database of candidate miRNAs and neuron-related target genes. Furthermore, miR-148a-3p acted as a apoptosis enhcaner via the activation of the SYNJ1/PI3K/Akt signaling pathway, highlighting a potential therapeutic target in the treatment of infants with hyperthermia-induced brain injury.


Asunto(s)
Apoptosis , MicroARNs/biosíntesis , Convulsiones Febriles/metabolismo , Transducción de Señal , Animales , Perfilación de la Expresión Génica , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosfatidilinositol 3-Quinasas/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Convulsiones Febriles/patología
12.
Chem Commun (Camb) ; 56(85): 13037-13039, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33001078

RESUMEN

A ratiometric fluorescent probe (N-butyl-4-(4-amino-styryl)-1,8-naphthalimide) was developed for the quantitative detection of styrene in air. The sensing mechanism was found to involve a Heck reaction between the pretreated probe (diazotization) and styrene. A probe solution absorption method was established to detect gaseous styrene quantitatively.

13.
Medicine (Baltimore) ; 98(49): e18055, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31804311

RESUMEN

The good recovery of hip function after THA depends on reconstruction of acetabular prosthesis accurately. So we investigated the effect of acetabular prosthesis placement on hip joint function after THA and analyzed the clinical data of 432 patients with unilateral THA retrospectively . The patients were followed-up to evaluate the Harris score and hip range of motion (ROM). The hip ROM, the Harris score and the good rate of Harris score were compared between different groups. Comparison of the good rate of Harris score showed that 85%∼100% group of the rotation center horizontal position ratio was higher than >100% group; 80%∼120% group of the rotation center vertical position ratio was higher than >160% group; and the 90%∼110% group and 110%∼130% group of femoral offset ratio were higher than 90% and >130% groups. Comparison of Harris score showed that 85%∼100% and 70%∼85% groups of rotation center horizontal position ratio were higher than 70% and >100% groups; 80%∼120% group of rotation center vertical position ratio was the highest; and 90%∼110% group and 110%∼130% group of femoral offset ratio were higher than >130% and 90% groups. Comparison of hip ROM showed that 85%∼100% and 70%∼85% groups of the rotation center horizontal position ratio were higher than 70% and >100% groups; 80%∼120% group of the rotation center vertical position ratio was the highest; and hip ROM from high to low are 90%∼110%, 110%∼130%, >130% and 90% groups of femoral offset ratio. These findings indicated that during the early follow-up period of THA, if the horizontal position of femoral head rotation center was reconstructed in 0.85 to 1 times of healthy side when compared with reconstruction >1 times of the healthy side and if the vertical position of femoral head rotation center was reconstructed in 0.8 to 1.2 times of the healthy side when compared with reconstruction in >1.6 times of the healthy side, better hip function recovery and optimal hip ROM were obtained. The optimal reconstruction range of femoral offset is 0.9 to 1.3 times of the healthy side.


Asunto(s)
Acetábulo/anatomía & histología , Artroplastia de Reemplazo de Cadera/métodos , Fémur/anatomía & histología , Prótesis de Cadera , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Falla de Prótesis , Recuperación de la Función , Estudios Retrospectivos
14.
Bioresour Technol ; 272: 99-104, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30316197

RESUMEN

A novel pretreatment strategy based on combination of microwave and ionic liquid [TBA][OH] was developed for enhancing enzymatic hydrolysis of Eucalyptus sawdust. The sugar yield of pretreated sample achieved 410.67 mg/g in 48 h, which suffered from optimized microwave-assisted [TBA][OH] pretreatment. The work mechanism was illuminated by chemical composition, Fourier transform infrared spectroscopy (FTIR), 13C cross polarization/magic-angle spinning solid state NMR (13C solid NMR), X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses. The combined effect of microwave and [TBA][OH] leads to the violent deconstruction of lignin, removal of hemicelluloses, destruction of crystalline region and an eroded, pored and irregular micro-morphology. As a green, relatively inexpensive and high efficient pretreatment, microwave-assisted [TBA][OH] pretreatment has great potential in the field of bio-refinery.


Asunto(s)
Eucalyptus/metabolismo , Microondas , Polisacáridos/metabolismo , Eucalyptus/química , Hidrólisis , Líquidos Iónicos/química , Lignina/química , Lignina/metabolismo , Polisacáridos/química , Agua , Madera
15.
Sleep Breath ; 23(1): 349-354, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29961182

RESUMEN

PURPOSE: Diabetes and sleep disorders are public health threats worldwide, but the potential association between them is still unclear. METHODS: We conducted a community-based cross-sectional study including 5078 participants (2665, 52.5% male) to determine the association between insomnia and diabetes mellitus prevalence. RESULTS: In patients with type 2 diabetes mellitus (T2DM) and nondiabetic controls, the prevalence of insomnia was 20.2% (68/377) and 12.2% (578/4741), respectively. The results showed that insomnia was associated with T2DM after adjusting for age, sex, BMI, smoking, alcohol consumption, presence of disease history (hypertension, dyslipidemia, stroke, cardiovascular diseases, cancers), and depression (odds ratio [OR] = 1.31, 95% confidence interval [CI] 1.03-1.66). After stratifying by age and sex, insomnia was significantly associated with diabetes mellitus only in the subgroup of middle-aged participants (40-59 years) (OR = 1.61, 95% CI 1.16-2.23) and males (OR = 1.48, 95% CI 1.08-2.03) after controlling for the above covariates. CONCLUSIONS: This study suggests that insomnia is independently and significantly associated with diabetes mellitus in the northern Chinese population, especially in the 40-59-year-old age group and in males.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Adulto , Factores de Edad , China , Correlación de Datos , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales
16.
Mol Med Rep ; 18(1): 1149-1154, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29845272

RESUMEN

A series of natural compounds have been implicated to be useful in regulating the pathogenesis of various autoimmune diseases. The present study demonstrated that the Scutellariae radix compounds baicalein and baicalin may serve as drugs for the treatment of autoimmune diseases, including rheumatoid arthritis and inflammatory bowel disease. Following the administration of baicalein and baicalin in vivo, T cell­mediated autoimmune diseases in the mouse model were profoundly ameliorated: In the collagen­induced arthritis model (CIA), the severity of the disease was reduced by baicalein and, consistently, baicalein was demonstrated to suppress T cell proliferation in CIA mice. In the dextran sodium sulfate (DSS)­induced colitis model, the disease was attenuated by baicalin, and baicalin promoted colon epithelial cell (CEC) proliferation in vitro. The present study further revealed that the mRNA expression of signal transducer and activator of transcription (STAT)3 and STAT4 in the tyrosine­protein kinase JAK­STAT signaling pathway in T cells was downregulated by baicalein, contributing to its regulation of T cell proliferation. However, in the DSS model, the STAT4 transcription in CECs, which are the target cells of activated T cells in the gut, was downregulated by baicalin, suggesting that baicalein and baicalin mediated similar STAT expression in different cell types in autoimmune diseases. In conclusion, the similarly structured compounds baicalein and baicalin selectively exhibited therapeutic effects on autoimmune diseases by regulating cell proliferation and STAT gene expression, albeit in different cell types.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Enfermedades Autoinmunes/tratamiento farmacológico , Colitis/tratamiento farmacológico , Flavanonas/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Artritis Experimental/inmunología , Artritis Experimental/patología , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/patología , Colitis/inducido químicamente , Colitis/inmunología , Colitis/patología , Sulfato de Dextran/toxicidad , Masculino , Ratones , Factor de Transcripción STAT3/inmunología , Factor de Transcripción STAT4/inmunología , Transducción de Señal/inmunología
17.
Bioresour Technol ; 254: 145-150, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29413915

RESUMEN

Two ultrasound-assisted pretreatment technologies, ultrasound-assisted alkaline and ultrasound-assisted aqueous ionic liquid tetrabutylammonium hydroxide ([TBA][OH]), are compared systematically in regard to enzymatic saccharification. Pretreated Eucalyptus samples were characterized by powder X-ray diffraction, 13C cross polarization/magic-angle spinning solid state NMR spectroscopy, Fourier transform infrared spectroscopy, Scanning electron microscope (SEM) and chemistry composition analysis. These results not only explain the enzymatic saccharification difference between samples from the microstructure level, but also provide helpful information for relevant pretreatment research. Ultrasound-assisted [TBA][OH] pretreatment acquired a significant enhancement in the initial enzymatic rate of cellulose (79.39 mg/g/h), and a reducing sugar yield of 426.6 mg/g at 48 h. The pretreatment combining inexpensive aqueous ionic liquid and ultrasound may provide a promising strategy in the field of bio-refinery because of its unique advantages.


Asunto(s)
Eucalyptus , Líquidos Iónicos , Resonancia Magnética Nuclear Biomolecular , Celulosa , Hidrólisis
18.
Chem Commun (Camb) ; 53(46): 6231-6234, 2017 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-28537289

RESUMEN

A ratiometric fluorescent probe based on anthracene carboximide was developed for direct detection of isocyanates in air. The sensing mechanism was illustrated to be variation in the photophysical properties caused by the nucleophilic reaction of the probe molecule. A number of isocyanates were conveniently detected by a test paper.

19.
Bioresour Technol ; 211: 443-50, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27035476

RESUMEN

The thermogravimetric and chemical characterization of hardwood Eucalyptus urophylla (Ep) and softwood Pinus massoniana (Mp) pretreated by brown-rot fungus Gloeophyllum trabeum were investigated. The results indicated that the brown-rot fungus pretreatment can optimize the thermal decomposition and decrease the initiation temperatures (8-11°C lower) of both the Ep and Mp pyrolysis. The mean activation energy values of the bio-treated samples were 29.7kJ/mol (for Ep) and 42.3kJ/mol (for Mp) lower than that of the un-treated samples at the conversion rate from 0.1 to 0.7 based on Flynn-Wall-Ozawa (FWO) method. After the bio-pretreatment, the required temperatures were lower (4-7°C) for the pyrolysis rates of hemicellulose and cellulose in Mp reaching maximum and termination. However, the situation was just the opposite for Ep. The variations in chemical properties of hydrogen bonding, as well as the relative changes in lignin/carbohydrate composition of both wood species were also examined.


Asunto(s)
Basidiomycota/metabolismo , Eucalyptus/metabolismo , Pinus/metabolismo , Termogravimetría/métodos , Madera/química , Biodegradación Ambiental , Celulosa/metabolismo , Enlace de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica
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