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1.
J Chem Phys ; 160(4)2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38284653

RESUMEN

The optical surface of extreme ultraviolet (EUV) lithography machines is highly vulnerable to contamination by hydrocarbons, resulting in the formation of carbon deposits that significantly degrade the quality and efficiency of lithography. The dynamic gas lock (DGL) has been proven as an effective approach to alleviate carbon deposition. However, the majority of existing studies on carbon deposition neglect the influence of the DGL. This paper is dedicated to investigating the phenomena of hydrocarbon adsorption, desorption, and cleavage with considering the effects of the DGL. A comprehensive mathematical model of the carbon deposition process is established, and the impact of radiation intensity, temperature, and hydrocarbon types on the depositing rate is considered. The results suggest that the primary cause of carbon deposition is the direct cracking of hydrocarbons induced by photons with a wavelength range between 12.5 and 14.5 nm. Additionally, it has been observed that the carbon deposition rate decreases exponentially as clean gas flow increases when EUV radiation intensity exceeds 50 mW/mm2. Conversely, at low EUV radiation intensity, clean gas flow has little effect on the carbon deposition rate. An effective approach to mitigate carbon deposition is to elevate the temperature of the optical surface and employ light hydrocarbon materials in the EUV process.

2.
Materials (Basel) ; 14(16)2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34443202

RESUMEN

In this study, the magnetic properties, coercivity mechanism, and magnetization reversal process were investigated for Ce-(Y)-Pr-Fe-B films. After the addition of Y and subsequent heating treatment, the formations of REO (RE ≡ Ce and Pr) and REFe2 (RE ≡ rare earths) phases are inhibited, and the microstructure of Ce-Y-Pr-Fe-B film is optimized. Meanwhile, the coercivity and the squareness of the hysteresis loop are significantly improved. The coercivity mechanism of Ce-Y-Pr-Fe-B film is determined to be a mixture of nucleation and pinning mechanisms, but dominated by the nucleation mechanism. The demagnetization results show that the nucleation of reversal magnetic domains leads to irreversible reversal. Our results are helpful to understand the coercivity mechanism and magnetization reversal of permanent magnetic films with multi-main phases.

3.
J Hazard Mater ; 349: 224-233, 2018 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-29427973

RESUMEN

A series of hollow structure lantern-like Eu(III)-doped g-C3N4 (xEu-CN, x = 1, 2, 3) was firstly synthesized by heating a mixture of melamine, HNO3 and Eu2O3 at 500 °C for 2 h. The phase, morphology and optical properties of the serial xEu-CN samples were characterized by different techniques, including TEM, XRD, FT-IR, SEM, XPS, BET, UV-vis, PL, photocurrent, and EIS. The results indicated that Eu doping extraordinarily enhanced the photocatalytic activity of pure g-C3N4, and the 2Eu-CN exhibited the highest photocatalytic performance with a 98% (82%) degradation rate for RhB (TC), 6.03 (1.71)-fold of pure g-C3N4(CN). The higher photocatalytic efficiency is ascribed to the synergy effect of Eu(III) and the hollow structures, which led to a larger surface specific area, bandgap narrowing, enhanced light harvesting ability and efficient charge separation.

4.
Water Sci Technol ; 73(5): 1190-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26942542

RESUMEN

To improve the excess sludge disintegration efficiency, reduce the sludge disintegration cost, and increase sludge biodegradability, a combined pretreatment of anaerobic hydrolysis (AH) and ultrasonic treatment (UT) was proposed for excess sludge. Results showed that AH had an advantage in dissolving flocs, modifying sludge characteristics, and reducing the difficulty of sludge disintegration, whereas UT was advantageous in damaging cell walls, releasing intracellular substances, and decomposing macromolecular material. The combined AH-UT process was an efficient method for excess sludge pretreatment. The optimized solution involved AH for 3 days, followed by UT for 10 min. After treatment, chemical oxygen demand, protein, and peptidoglycan concentrations reached 3,949.5 mg O2/L, 752.5 mg/L and 619.1 mg/L, respectively. This work has great significance for further engineering applications, namely, reducing energy consumption, increasing the sludge disintegration rate, and improving the biochemical properties of sludge.


Asunto(s)
Aguas del Alcantarillado/química , Ultrasonido , Anaerobiosis , Bacterias/citología , Bacterias/metabolismo , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Hidrólisis , Proteínas/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua
5.
Chin J Integr Med ; 18(7): 534-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22772917

RESUMEN

Many schools of academic doctrines have emerged throughout the development history of traditional Chinese medicine (TCM) due to geographic, time, Shicheng (mentor-apprentice system) and academic diversities. Classic TCM School, Classic Formula School and Febrile Disorder School, though all lacking a clearly demonstrable or continuous Shicheng relationship, are nevertheless so classified because of their consistency in reference to the classic TCM works. Each of the Four Famous Masters of Jin and Yuan Dynasties had its distinctively different academic doctrine, resulting in the establishment of individually integrated academic schools. The emergence of the Warming and Tonifying School in late Yuan and early Ming Dynasties was realized as a means to rectify the ill effects of the cool and cold medications prevalent at the time. On the other hand, the advent of the Warm Disease School and the rise of the Confluence School embodied the close relationship carried by TCM academic schools to contemporary historical background. Looking at this development history, it is evident that the development of TCM academic schools could flourish only if it allows dissenting, yet mutually tolerant, opinions. In present medical environment where TCM and Western medicine are of equal importance, Classic TCM Schools, TCM Modernization Schools and Integrative Medicine Schools should all receive emphasis to foster development.


Asunto(s)
Medicina Tradicional China , Escuelas para Profesionales de Salud , Academias e Institutos , Escuelas para Profesionales de Salud/clasificación , Libros de Texto como Asunto
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