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1.
Small ; 20(5): e2305948, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759414

RESUMEN

The large-scale commercialization of the hydrogen evolution reaction (HER) necessitates the development of cost-effective and highly efficient electrocatalysts. Although transition metal sulfides, such as MoS2 and Ni3 S2 , hold great potential in the field of HER, their catalytic performance has been unsatisfactory due to incomplete exposure of active sites and poor electrical conductivity. In this work, via a simple hydrothermal strategy, amorphous MoS2 nanoshells in the form of urchin-like MoS2 -Ni3 S2 core-shell heterogeneous structure is realized and in situ loaded on nickel foam (A-MoS2 -Ni3 S2 -NF). In particular, XPS analysis results show that the coupling of amorphous MoS2 and Ni3 S2 makes the electrode surface exhibit electron-abundant property, which will have a positive impact on HER catalytic activity. In addition, the fully exposed active site of amorphous MoS2 is another crucial factor contributing to its high catalytic performance of A-MoS2 -Ni3 S2 -NF electrode. In particular, at a current density of 10 mA cm⁻2 , the overpotential of electrode is 95 mV (1.0 m KOH) and 145 mV (0.5 m H2 SO4 ). This work highlights the importance of amorphous MoS2 and MoS2 -Ni3 S2 of sea-urchin core-shell structure in optimizing HER performance, which provides an important reference for HER research.

2.
J Nanobiotechnology ; 22(1): 448, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080692

RESUMEN

It is of great significance to develop a novel approach to treat bacterial infections, as the frequent misuse of antibiotics leads to the serious problem of bacterial resistance. This study proposed antibiotic-free antibacterial nanoparticles for eliminating methicillin-resistant Staphylococcus aureus (MRSA) based on a multi-model synergistic antibacterial ability of chemodynamic therapy (CDT), photothermal effect, and innate immunomodulation. Specifically, a polydopamine (PDA) layer coated and Ag nanoparticles loaded core-shell structure Fe3O4 nanoparticles (Fe3O4@PDA-Ag) is prepared. The Fe3O4 catalyzes H2O2 present in acidic microenvironment of bacterial infection into more toxic reactive oxygen species (ROS) and synergizes with the released Ag ions to exert a stronger bactericidal capacity, which can be augmented by photothermal action of PDA triggered by near-infrared light and loosen the biofilm by photothermal action to promote the penetration of ROS and Ag ion into the biofilm, result in disrupting biofilm structure along with killing encapsulated bacteria. Furthermore, Fe3O4@PDA-Ag exerts indirect antibacterial effects by promoting M1 macrophage polarizing. Animal models demonstrated that Fe3O4@PDA-Ag effectively controlled MRSA-induced infections through photothermal enhanced CDT, Ag+ releasing, and macrophage-mediated bactericidal properties. The acid-triggered antibacterial nanoparticles are expected to combat drug-resistant bacteria infection.


Asunto(s)
Antibacterianos , Biopelículas , Indoles , Macrófagos , Staphylococcus aureus Resistente a Meticilina , Especies Reactivas de Oxígeno , Plata , Infecciones Estafilocócicas , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Animales , Ratones , Indoles/química , Indoles/farmacología , Plata/química , Plata/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Macrófagos/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Biopelículas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Polímeros/química , Polímeros/farmacología , Células RAW 264.7 , Nanopartículas del Metal/química , Nanopartículas/química , Terapia Fototérmica/métodos
3.
Inorg Chem ; 54(18): 9046-59, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26331268

RESUMEN

A series of uranyl-organic frameworks (UOFs), {[(UO2)2(H2TTHA)(H2O)]·4,4'-bipy·2H2O}n (1), {[(UO2)3(TTHA)(H2O)3]}n (2), and {[(UO2)5(TTHA) (HTTHA)(H2O)3]·H3O}n (3), have been obtained by the hydrothermal reaction of uranyl acetate with a flexible hexapodal ligand (1,3,5-triazine-2,4,6-triamine hexaacetic acid, H6TTHA). These compounds exhibited three distinct 3D self-assembly architectures as a function of pH by single-crystal structural analysis, although the used ligand was the same in each reaction. Surprisingly, all of the coordination modes of the H6TTHA ligand in this work are first discovered. Furthermore, the photoluminescent results showed that these compounds displayed high-sensitivity luminescent sensing functions for nitrobenzene. Additionally, the surface photovoltage spectroscopy and electric-field-induced surface photovoltage spectroscopy showed that compounds 1-3 could behave as p-type semiconductors.


Asunto(s)
Acetatos/química , Complejos de Coordinación/química , Luminiscencia , Semiconductores , Triazinas/química , Uranio/química , Concentración de Iones de Hidrógeno , Ligandos , Conformación Molecular , Nitrobencenos/análisis
4.
Zhonghua Yi Xue Za Zhi ; 94(31): 2452-4, 2014 Aug 19.
Artículo en Zh | MEDLINE | ID: mdl-25400055

RESUMEN

OBJECTIVE: To evaluate the effects of rosuvastatin on arterial stiffness in hyperlipidemia patient without hypertension. METHODS: A total of 60 patients without hypertension received rosuvastatin (10 mg, n = 60) daily for 12 weeks while another 60 subjects used no statins. Brachial-ankle pulse wave velocity (ba-PWV), radial artery augmentation index of reflected wave (rAI) and metabolic index were measured before and after treatment. RESULTS: There were no significant change before and after non-statin treatment. Total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) levels decreased dramatically after resuvastin treatment [TC: (4.0 ± 1.0) vs (5.8 ± 1.1) mmol/L; LDL-C: (2.1 ± 0.7) vs (3.8 ± 0.7) mmol/L, both P < 0.01]. In rosuvastatin group, ba-PWV and rAI decreased significantly [ba-PWV: (1 340 ± 177) vs (1 477 ± 159) cm/s; rAI: (44 ± 13) % vs (57 ± 15) %, P < 0.01 and P < 0.05). CONCLUSION: Atherosclerosis may be improved by rosuvastatin treatment in hyerlipidemia patient without hypertension.


Asunto(s)
Índice Tobillo Braquial , Hiperlipidemias , Rigidez Vascular , Articulación del Tobillo , Aterosclerosis , Velocidad del Flujo Sanguíneo , LDL-Colesterol , Fluorobencenos , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Hipertensión , Flujo Pulsátil , Pirimidinas , Rosuvastatina Cálcica , Sulfonamidas
5.
Int J Biol Macromol ; 255: 127989, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37977469

RESUMEN

Electrically conductive metal-organic frameworks (EC-MOFs) have attracted great attentions in electrochemical fields, but their practical application is limited by their hard-to-shape powder form. The aims was to integrate continuously nucleated EC-MOFs on natural wood cellulose scaffold to develop biobased EC-MOFs membrane with robust flexibility and improved electrochemical performance for wearable supercapacitors. EC-MOF materials (NiCAT or CuCAT) were successfully incorporated onto porous tempo-oxidized wood (TOW) scaffold to create ultrathin membranes through electrostatic force-mediated interfacial growth and simple room-temperature densification. The studies demonstrated the uniform and continuous EC-MOFs nanolayer on TOW scaffold and the interfacial bonding between EC-MOF and TOW. The densification of EC-MOF@TOW bulk yielded highly flexible ultrathin membranes (about 0.3 mm) with high tensile stress exceeding 180 MPa. Moreover, the 50 %-NiCAT@TOW membrane demonstrated high electrical conductivity (4.227 S·m-1) and hydrophobicity (contact angle exceeding 130°). Notably, these properties remained stable even after twisting or bending deformation. Furthermore, the electrochemical performance of EC-MOF@TOW membrane with hierarchical pores outperformed the EC-MOF powder electrode. This study innovatively anchored EC-MOFs onto wood through facile process, yielding highly flexible membranes with exceptional performance that outperforms most of reported conductive wood-based membranes. These findings would provide some references for flexible and functional EC-MOF/wood membranes for wearable devices.


Asunto(s)
Estructuras Metalorgánicas , Madera , Polvos , Electricidad , Conductividad Eléctrica , Celulosa
6.
EMBO Mol Med ; 16(5): 1051-1062, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38565805

RESUMEN

The emergence of drug-resistant Enterobacteriaceae carrying plasmid-mediated ß-lactamase genes has become a significant threat to public health. Organisms in the Enterobacteriaceae family containing New Delhi metallo-ß-lactamase­1 (NDM-1) and its variants, which are capable of hydrolyzing nearly all ß-lactam antibacterial agents, including carbapenems, are referred to as superbugs and distributed worldwide. Despite efforts over the past decade, the discovery of an NDM-1 inhibitor that can reach the clinic remains a challenge. Here, we identified oxidized glutathione (GSSG) as a metabolic biomarker for blaNDM-1 using a non-targeted metabolomics approach and demonstrated that GSSG supplementation could restore carbapenem susceptibility in Escherichia coli carrying blaNDM-1 in vitro and in vivo. We showed that exogenous GSSG promotes the bactericidal effects of carbapenems by interfering with intracellular redox homeostasis and inhibiting the expression of NDM-1 in drug-resistant E. coli. This study establishes a metabolomics-based strategy to potentiate metabolism-dependent antibiotic efficacy for the treatment of antibiotic-resistant bacteria.


Asunto(s)
Antibacterianos , Carbapenémicos , Escherichia coli , Glutatión , beta-Lactamasas , beta-Lactamasas/metabolismo , beta-Lactamasas/genética , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Carbapenémicos/farmacología , Antibacterianos/farmacología , Animales , Glutatión/metabolismo , Pruebas de Sensibilidad Microbiana , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Ratones , Metabolómica , Oxidación-Reducción/efectos de los fármacos , Humanos
7.
Artículo en Zh | MEDLINE | ID: mdl-38114320

RESUMEN

Laryngeal hamartoma is a benign proliferative tumor-like lesion that occurs in the larynx. A case of supraglotic laryngeal hamartoma admitted by our department and 12 cases of laryngeal hamartoma reported in literature were retrospectively analyzed, the pathogenesis, clinicalmanifestation, diagnosis, treatment and prognosis of laryngeal hamartoma was explored, aiming to improve the understanding and diagnosis and treatment.of this disease.


Asunto(s)
Hamartoma , Neoplasias Laríngeas , Laringe , Humanos , Niño , Estudios Retrospectivos , Laringe/patología , Laringoscopía , Pronóstico , Neoplasias Laríngeas/cirugía
8.
Artículo en Zh | MEDLINE | ID: mdl-33540976

RESUMEN

Objective:To analyze the follow-up results of children with different types of auricle deformities after non-invasive correction, to understand the rebound rate of the children after correction, so as to provide corresponding guidance for improving the correction effect of the children's auricle. Methods:During the correction period, follow up once a day through WeChat, and once every 2 days after the correction, lasting 1 week,and if there was no change, the last follow-up was carried out after 1 month. Results:Thirty-three cases with ear deformities were corrected, 6 cases of cryptotia, 4 cases of cup ear, 9 cases of ear tubercle malformation,4 cases of lope ear, 4 cases of constricted ear, 3 cases of prominent ear, 1 case of cryptotia mixed constricted ear, 2 cases of cryptotia mixed prominent ear. The age of 7 d to 9 months, all were corrected with EarWell non-invasive corrective system, correction duration time was 3 weeks to 6 months. Conclusion:The age requirements for correction of hidden ear deformities are relatively loose, and they can be corrected within 1 year old, and the correction time is about one month. With good parental post-correction care, the rebound rate is almost 0; children with ring-shaped ear deformities , Requires higher age, longer correction time, up to 6 months, rebound rate is inversely proportional to correction time. The correction time of children with helix deformity and lop ears is inversely proportional to the age of the children. Good nursing can reduce the rebound rate of auricle deformity and improve the correction effect.


Asunto(s)
Anomalías Congénitas , Pabellón Auricular , Procedimientos de Cirugía Plástica , Niño , Anomalías Congénitas/cirugía , Pabellón Auricular/cirugía , Oído Externo/cirugía , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Cuello , Padres
9.
J Hazard Mater ; 405: 124275, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33092881

RESUMEN

Understanding of neonicotinoid insecticides toxicity on non-target organisms, such as bees, has indirectly promoted their soil treatment use. However, their effect on soil ecosystems haven't fully understood. Here, based on 16S rRNA high-throughput sequencing and metagenomics, the effects of neonicotinoid insecticide thiamethoxam on bacterial communities and metabolic functions in two types of soils were studied. Thiamethoxam treatment significantly affected soil bacterial abundance, reduced microbial diversity, and changed the bacterial community structure in the short term, and the structure soon returned to a stable state. Soil type and time were important factors affecting bacterial community structure. Some plant growth-promoting rhizosphere bacteria (PGPR) including Actinobacteria were found, and their populations were reduced, while pollutant-degrading bacteria including Firmicutes were also found, and their populations were increased. Based on metagenomics analysis, thiamethoxam treatment insignificantly promoted or inhibited multiple metabolic processes, but gene abundance of some key processes significantly changed. Subtypes of 18 biodegradation genes (BDGs) and 5 pesticide degradation genes (PDGs) were identified. Thiamethoxam treatment significantly increased the abundance of BDGs and PDGs, including cytochrome P450. Potential hosts of P450 degradation genes, including the genus Rhodococcus, were discovered. Conclusions of this study will promote safety evaluation and degradation-related research on neonicotinoid insecticides in soil.


Asunto(s)
Insecticidas , Animales , Bacterias/genética , Abejas , Ecosistema , Insecticidas/análisis , Insecticidas/toxicidad , Neonicotinoides/toxicidad , ARN Ribosómico 16S/genética , Suelo , Microbiología del Suelo , Tiametoxam
10.
ACS Appl Mater Interfaces ; 11(46): 43146-43155, 2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31647215

RESUMEN

The original poly(ethylene oxide)-based polymer electrolytes normally show low ionic conductivity and inferior mechanical property, which greatly restrict their practical application in all-solid-state lithium-ion batteries (LIBs). In this work, a hyperbranched star polymer with poly(ethylene glycol) methyl ether methacrylate flexible chain segments is embedded into a three-dimensional (3D) interpenetrating cross-linking network created by the rapid one-step UV-derived photopolymerization of the cross-linker (ethoxylated trimethylolpropane triacrylate) in the presence of lithium salt. The rigid 3D network framework provides the polymer electrolyte with not only enhanced mechanical behavior, including film-forming and dendrite-inhibiting capabilities, but also nanoconfinement effects, which can speed up polymer chain segmental dynamics and reduce the crystallinity of the polymer. Depending on this unique rigid-flexible coupling network, the prepared solid polymer electrolyte shows enhanced ionic conductivity (6.8 × 10-5 S cm-1 at 50 °C), widened electrochemical stability window (5.1 V vs Li/Li+), and enough mechanical stability to suppress the growth of uneven Li dendrite (the Li symmetrical cells can operate steadily at both current densities of 0.05 and 0.1 mA cm-2 for 1000 h). Moreover, the assembled LiFePO4//Li cell also exhibited good cycle performance at 50 °C, making the hyperbranched star polymer electrolyte with a nanoconfined cross-linking structure to have potential application in high-safety and high-performance LIBs.

11.
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
12.
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
13.
ACS Appl Mater Interfaces ; 10(30): 25273-25284, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29975039

RESUMEN

All-solid-state polymer electrolytes (SPEs) have aroused great interests as one of the most promising alternatives for liquid electrolyte in the next-generation high-safety, and flexible lithium-ion batteries. However, some disadvantages of SPEs such as inefficient ion transmission capacity and poor interface stability result in unsatisfactory cyclic performance of the assembled batteries. Especially, the solid cell is hard to be run at room temperature. Herein, a novel and flexible discotic liquid-crystal (DLC)-based cross-linked solid polymer electrolyte (DLCCSPE) with controlled ion-conducting channels is fabricated via a one-pot photopolymerization of oriented reactive discogen, poly(ethylene glycol)diacrylate, and lithium salt. The experimental results indicate that the macroscopic alignment of self-assembled columns in the DLCCSPEs is successfully obtained under annealing and effectively immobilized via the UV photopolymerization. Because of the existence of unique oriented structure in the electrolytes, the prepared DLCCSPE films exhibit higher ionic conductivities and better comprehensive electrochemical properties than the DLCCSPEs without controlled ion-conductive pathways. Especially, the assembled LiFePO4/Li cells with oriented electrolyte show an initial discharge capacity of 164 mA h g-1 at 0.1 C and average specific discharge capacities of 143, 135, and 149 mA h g-1 at the C-rates of 0.5, 1, and 0.2 C, respectively. In addition, the solid cell also shows the first discharge capacity of 124 mA h g-1 (0.2 C) at room temperature. The outstanding cell performance of the oriented DLCCSPE should be originated from the macroscopically oriented and self-assembled DLC, which can form ion-conducting channels. Thus, combining the excellent performance of DLCCSPE and the simple one-pot fabricating process of the DLC-based all-solid-state electrolyte, it is believed that the DLC-based electrolyte can be one of the most promising electrolyte materials for the next-generation high-safety solid lithium-ion batteries.

14.
PLoS One ; 12(9): e0185267, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28934338

RESUMEN

Environmental stress, such as oxygen deprivation, affects various cellular activities and developmental processes. In this study, we directly investigated Drosophila embryo development in vivo while cultured on a microfluidic device, which imposed an oxygen gradient on the developing embryos. The designed microfluidic device enabled both temporal and spatial control of the local oxygen gradient applied to the live embryos. Time-lapse live cell imaging was used to monitor the morphology and cellular migration patterns as embryos were placed in various geometries relative to the oxygen gradient. Results show that pole cell movement and tail retraction during Drosophila embryogenesis are highly sensitive to oxygen concentrations. Through modeling, we also estimated the oxygen permeability across the Drosophila embryonic layers for the first time using parameters measured on our oxygen control device.


Asunto(s)
Drosophila melanogaster/embriología , Embrión no Mamífero/embriología , Embrión no Mamífero/metabolismo , Desarrollo Embrionario , Oxígeno/metabolismo , Animales , Movimiento Celular , Drosophila melanogaster/metabolismo , Embrión no Mamífero/citología , Dispositivos Laboratorio en un Chip , Modelos Biológicos , Permeabilidad
16.
Medicine (Baltimore) ; 96(44): e8237, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29095253

RESUMEN

The aim of the study is to investigate the advantages and disadvantages of low-temperature radiofrequency ablation of pharyngolaryngeal cyst.The study population was composed of 84 children diagnosed with pharyngolaryngeal cyst who underwent surgical treatment at the Department of Otolaryngology, Wuhan Children's Hospital, Wuhan, China, between January 1984 and December 2013. All patients were operated using a self-retaining laryngoscope and were divided into 3 groups: traditional cystectomy group (N = 9), dynamic cutting system group (N = 18), and low-temperature radiofrequency ablation group (N = 57). Clinical outcomes were analyzed to assess the efficacy of low-temperature radiofrequency ablation in treatment of pharyngolaryngeal cyst.Compared with traditional cystectomy group or dynamic cutting system group, operation time was shorter, bleeding was less and one-year recurrence rate was much lower in low-temperature radiofrequency ablation group. However, operation time and bleeding was not statistically different between traditional cystectomy and dynamic cutting system group.Low-temperature radiofrequency ablation may be an effective substitute for treating pharyngolaryngeal cyst.


Asunto(s)
Ablación por Catéter , Criocirugía , Quistes/cirugía , Enfermedades de la Laringe/cirugía , Enfermedades Faríngeas/cirugía , China , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
18.
Technol Health Care ; 24(5): 775-80, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27233088

RESUMEN

To evaluate the feasibility and effectiveness of using endoscopic low-temperature plasma radiofrequency ablation (RFA) for treatment of laryngeal plexiform neurofibromatosis-1 (NF-1). An infant diagnosed as laryngeal plexiform NF-1 based on a detailed medical history, as well as physical, laboratory, and pathological examinations, was treated under general anesthesia with low-temperature plasma RFA in combination with a self-retaining laryngoscope and high definition camera system.The laryngeal plexiform NF-1 tumor was successfully excised using endoscopic low-temperature plasma RFA without complications. Following surgery, the infant displayed an uneventful recovery and no disease recurrence during a 2-year follow-up period. low-temperature plasma RFA is a feasible and effective method for treating laryngeal plexiform NF-1, and has advantages of producing minimal bleeding, providing complete removal of the tumor, and causing only slight degrees of trauma and postoperative tissue reaction.


Asunto(s)
Ablación por Catéter/instrumentación , Neoplasias Laríngeas/cirugía , Neurofibroma Plexiforme/cirugía , Temperatura , Ablación por Catéter/métodos , Endoscopía del Sistema Digestivo/métodos , Humanos , Lactante , Masculino
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
20.
Artículo en Inglés | MEDLINE | ID: mdl-27038580

RESUMEN

A metal-organic complex [Cd2(L)(N3)4]·DMF was prepared by the reaction of Cd(NO3)2·4H2O, NaN3 and ligand L (L: 1,4-bis(bis(3,5-dimethyl-1H-pyrazol-1-yl)methyl)benzene) in a DMF system. And the complex was characterized by elemental analysis, IR spectroscopy, UV-vis spectroscopy, thermal gravimetric technology, X-ray powder diffraction and single-crystal X-ray diffraction. Furthermore, the complex was combined with Bi2WO6 to form a composite, which was used as photocatalyst to degrade the basic dye methylene blue (MB) under the Xe lamp irradiation. The result revealed that the photocatalytic activity of the composite was better than that of the pure Bi2WO6 and the complex. In addition, the mechanism of the photocatalysis was also studied.

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