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1.
Bioresour Technol ; 389: 129816, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37793553

RESUMEN

This research comprehensively investigates the co-pyrolysis of sewage sludge (SS) and waste tobacco stem (WTS). Various SS and WTS ratios (1:0, 0.75:0.25, 0.50:0.50, 0.25:0.75, and 0:1) were tested over a range of heating rates (30 °C to 800 °C). Apparent activation energies were calculated using model-free methods, and the co-pyrolysis mechanism was described with the master plot method. Results suggest that SS and WTS co-pyrolysis follows power-law models (P3, P4). Among blends, S75W25 exhibited optimal synergy, with the lowest activation energy required for the pyrolysis reactions and inhibits CO2 emissions. S75W25's pyrolysis gas primarily contained acids (e.g., ethylxanthogenacetic acid, acetic acid), hydrocarbons (e.g., supraene, cyclopropyl carbinol), and other compounds (e.g., CO2, pyrazine, pyridine, indole). ANN was utilized to forecast the temperature-mass loss relationships in co-pyrolysis, with the optimal model being ANN21, yielding a high correlation coefficient (R2 = 0.99999). This study offers guidance for the efficient utilization of waste SS and WTS.


Asunto(s)
Nicotiana , Aguas del Alcantarillado , Dióxido de Carbono , Pirólisis , Cinética , Redes Neurales de la Computación
3.
BMC Anesthesiol ; 22(1): 260, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35971080

RESUMEN

BACKGROUND: The mainstream facilitation of one-lung ventilation is using double-lumen endobronchial tubes. However, it is more difficult to be positioned properly and more likely to cause airway injuries. How to place double-lumen endobronchial tubes rapidly and correctly is important for thoracic anesthesiologists. METHODS: One hundred eight patients with an American Society of Anesthesiologists physical status of I to III were 20 years of age or over, and required one-lung ventilation for thoracic surgery. They were randomly assigned to the conventional technique group (n = 36), the flexible fiberoptic bronchoscopy group (n = 36), or the Trachway® flexible stylet group (n = 36). The primary endpoint was the time needed for intubation. T1, the time from the tip of the blade passing between the patient's lips to identification of the vocal cords; and T2, the time from identification of the vocal cords to the bronchial lumen was in the correct position. RESULTS: T1 had no significant difference between groups, but T2 was significantly shorter in the Trachway® flexible stylet group (p < 0.0001) and longer in the conventional technique group (p < 0.0001). CONCLUSIONS: Using Trachway® flexible stylet for correct placement of double-lumen endobronchial tubes not only significantly shortened the intubation time, but also reduced incidence of carinal injuries. It is an alternative, and a choice with good safety. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02364622, 18/02/2015, Retrospectively registered.


Asunto(s)
Intubación Intratraqueal , Ventilación Unipulmonar , Bronquios , Broncoscopía/métodos , Humanos , Intubación Intratraqueal/métodos , Estudios Prospectivos
4.
Bioresour Technol ; 360: 127539, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35777640

RESUMEN

Tobacco stems (TS) are tobacco residues produced, whereby the assessment of the pyrolysis kinetics of TS is critical to realize high-value utilization of agricultural residues. Firstly, a thermogravimetric analyzer was employed to perform the non-isothermal pyrolysis of TS at various heating rates. Then, the deconvolution function by Asym2sig showed that the pyrolysis of TS can be accurately modeled for three parallel decomposition fractions. Furthermore, the pyrolysis product was analyzed using fourier transform infrared spectrometer (FTIR). The results showed that the average activation energy evaluated by the isoconversion methods exhibited the highest average activation energy of 191.762 kJ·mol-1 for lignin (LG), followed by 189.268 kJ·mol-1 for cellulose (CL) and then 176.357 kJ·mol-1 for hemicellulose (HC). Based on the experimental results, the pre-exponential factors and reaction models for HC, CL and LG were also calculated and developed separately. From thermodynamic standpoint, raw materials for bioenergy generation can be derived from TS.


Asunto(s)
Nicotiana , Pirólisis , Biomasa , Celulosa/química , Cinética , Lignina/química , Termogravimetría
5.
J Org Chem ; 81(1): 25-31, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26624930

RESUMEN

A conversion of pyridines and enamides for the synthesis of 3-bromo-imidazo[1,2-a]pyridines was developed by copper-mediated aerobic oxidative coupling in a one-pot manner. This procedure tolerates various functional groups and affords a series of 3-bromo-imidazo[1,2-a]pyridines under mild conditions.

6.
Endoscopy ; 45(11): 907-14, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24165817

RESUMEN

BACKGROUND AND STUDY AIMS: The best anesthesia methods for analgesia and sedation during gastrointestinal endoscopy are still debated. The aim of this study was to compare the recovery time, clinical presentations, and satisfaction between target-controlled infusion (TCI) and manually controlled infusion (MCI) in same-day bidirectional endoscopy (esophagogastroduodenoscopy followed by colonoscopy). PATIENTS AND METHODS: A total of 220 patients with American Society of Anesthesiology physical status 1 or 2 were enrolled and randomized into the TCI or MCI groups. The clinical presentations, vasoactive drug demand, propofol consumption, and adverse events were recorded for both groups peri-procedurally. The concentrations of propofol in the plasma (Cp) and at the site of drug effect (Ce) by computerized simulation were also monitored in both groups. Finally, the satisfaction of patients, endoscopists, and nurse anesthetists was assessed by questionnaire after the examinations. RESULTS: Compared with the MCI group, the TCI group had a faster recovery time (17.91 ± 7.72 minutes vs. 14.58 ± 8.55 minutes; P = 0.002), less moderate hypotension (7.37 ± 15.46 % vs. 1.82 ± 5.15 %; P < 0.001), and shorter period of bradypnea (13.81 ± 15.92 % vs. 9.18 ± 12.00 %; P = 0.013). In addition, the TCI group reduced the relative risk of moderate desaturation by 50 % compared with the MCI group (30.9 % vs. 15.5 %; 95 % confidence interval 1.191-3.360; P = 0.007). CONCLUSIONS: The study demonstrated that TCI of propofol combined with alfentanil was associated with a faster recovery time, and better hemodynamic and respiratory stability than MCI in same-day bidirectional endoscopy. CLINICAL TRIAL REGISTRATION: CGMH IRB Identifier 97-0969B.


Asunto(s)
Alfentanilo/administración & dosificación , Anestésicos Intravenosos/administración & dosificación , Colonoscopía , Endoscopía del Sistema Digestivo , Propofol/administración & dosificación , Adulto , Periodo de Recuperación de la Anestesia , Actitud del Personal de Salud , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Satisfacción del Paciente , Encuestas y Cuestionarios
7.
J Org Chem ; 75(15): 5395-7, 2010 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-20590089

RESUMEN

A straightforward method for the synthesis of polysubstituted pyrroles was achieved easily from oxidative cyclization of beta-enamino ketones or esters and alkynoates catalyzed by CuI in the presence of O(2).


Asunto(s)
Ácidos Carboxílicos/química , Cobre/química , Cetonas/química , Oxígeno/química , Pirroles/química , Catálisis , Espectroscopía de Resonancia Magnética , Espectrometría de Masas
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