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The identification, evaluation, and prevention of micro internal short circuits (ISCs) are crucial for the safety of large-capacity high-energy-density (HED) Li-ion cells. However, the evolution mechanism and the premonitory signals of the micro ISCs are not yet completely understood. Via a high-precision penetration test and accelerating rate calorimetry, we successfully trigger and investigate on-demand ISCs on a 60 Ah HED (≥ 290 Wh kg–1) Li-ion pouch cell with Si-based anode/Ni-rich cathode couple. Detailed behaviors of the cell components during micro ISCs, such as pinhole and crack formation, pore-closing, and rupture of the separators, as well as the destruction of positive electrodes and fusion of Al current collectors, are observed. Moreover, the correlation of these internal effects with external cell signals is identified. We demonstrate that voltage change signals, even at millivolt level, are noteworthy and can be used as premonitory signals for early warning of micro ISCs and leading indicators for predicting cell thermal runaway. The disclosed micro ISC propagation, alleviation, and acceleration mechanisms could guide the design of safe HED Li-ion cells.

El objetivo principal de la presente tesis es analizar los errores que cometen los estudiantes españoles de diferentes niveles de chino en sus trabajos de expresión escrita en esta lengua, para encontrar el patrón de los errores e indagar en sus posibles causas, con el fin último de sentar las bases para poder diseñar estrategias más efectivas de enseñanza del chino como lengua extranjera para estudiantes hispanohablantes. Para lograr dicho objetivo, basándonos en una revisión global de los estudios anteriores sobre análisis de errores de chino como lengua extranjera, y sobre análisis contrastivo entre el español y el chino, hemos elaborado una taxonomía de errores a tres niveles de análisis —a saber, el nivel léxico, el nivel oracional y el nivel discursivo. Además, hemos elaborado una base de datos formados por los errores sacados de 120 trabajos de expresión escrita en chino de alumnos universitarios españoles, de diferentes grados y cursos académicos y que tienen un nivel de chino entre el A1 al B1 del Marco Europeo Común de Referencia (MCER). A partir del corpus, hemos hecho un análisis tanto cuantitativo como cualitativo de acuerdo con tres parámetros: el nivel de análisis de errores, el nivel de chino de los alumnos y la tipología de los errores. Dicho análisis nos permite conocer cuáles son los errores más frecuentes en cada nivel de lengua y de análisis a lo largo de su proceso de aprendizaje, los usos de chino que presentan mayor dificultad de dominio, la evolución de los errores y sus posibles causas. La presente investigación representa una aportación por ser el primer análisis de errores con la combinación lingüística de chino-español y por la metodología empleada en la sistematización del análisis de errores. Este trabajo sienta las bases para abrir nuevas vías para futuras investigaciones sobre el análisis de errores en el aprendizaje del chino y la enseñanza de chino como lengua extranjera en general. The main objective of this thesis is to analyze the errors made by Spanish students of different levels of Chinese in their Chinese written works, in order to find the pattern of errors and their possible causes, with the ultimate goal to lay the foundations for designing more effective strategies for teaching Chinese as a foreign language to Spanish-speaking students. To achieve this goal, based on a global review of previous studies on error analysis of Chinese as a foreign language, and on contrastive analysis between Spanish and Chinese, we have developed a taxonomy of errors at three levels of analysis —the lexical level, the sentence level and the discourse level. In addition, we have developed a database formed by the errors taken from 120 compositions written in Chinese by Spanish university students from different grades and academic courses with a Chinese level between A1 to B1 of the Common European Framework of Reference for languages (CEFR). From the corpus, we have made a quantitative and qualitative analysis according to three parameters: the level of error analysis, the level of Chinese students and the type of errors. This analysis allows us to know what are the most frequent errors in each Chinese level and analysis level throughout their learning process, the Chinese expressions or structures that present greater difficulty of mastery, the error evolution and their possible causes. This research makes a contribution for being the first error analysis with the Chinese-Spanish linguistic combination and the methodology used in the systematization of error analysis. This work also lays the groundwork for opening new ways for future work on the error analysis in Chinese learning and on teaching Chinese as a foreign language.

N-Methylpyrrolidone (NMP), a kind of nitrogen-containing heterocyclic pollutant, is widely used in chemical industry. Microbial degradation is an important environmental fate process in soil and water, however, the microbial metabolic mechanism is still unknown. Strain NMD-4, capable of utilizing NMP as the sole source of carbon and nitrogen, was isolated from the activated sludge of a pesticide plant in Jiangsu, China, and identified as Paracoccus sp. based on its physiological–biochemical properties, as well as 16S rRNA gene sequence analysis. The degradation characteristic of NMP by strain NMD-4 was studied in a liquid culture, and the metabolic pathway of NMP by the strain was investigated. Two metabolites, 1-methyl-2,5-pyrrolidinedione and succinic acid, were detected and identified by liquid chromatography-mass spectrometry analysis, and a plausible microbial degradation pathway of NMP was proposed by the first time.

A pesar de que el concepto de tema o tópico ha sido ampliamente estudiado tanto en chino como en español, no lo ha sido así su estructura temática desde un punto de vista contrastivo. A partir de la teoría de Loar (2011) se ha realizado dicho análisis y los resultados indican que el chino no solo usa más construcciones topicalizadas que el español, sino que también cuenta con más diversidad de construcciones de este tipo, a pesar de que dispone de una menor flexibilidad en la posición que puede ocupar el tópico dentro de la oración. Ambas lenguas coinciden en la posibilidad de llevar topicalizadores, así como en los elementos que pueden constituir el tópico. Todos estos aspectos se ilustran con numerosos ejemplos a lo largo del trabajo, a la vez que se sugieren posibles equivalencias, por lo que esta contribución puede llenar un vacío investigativo en la didáctica de la Lenguas Extranjeras y de la Traducción Although the concept of theme or topic has been widely researched both in Chinese and Spanish, no studies have been carried out about their thematic structure from the perspective of contrastive linguistics. Taking Loar's theory (2011) as a starting point, we have carried out a contrastive analysis and the results show that Chinese has not only a higher tendency to use topicalised constructions than Spanish, but also a wider range of constructions of this type. Both languages can use topicalisers and have also in common the word classes that can occupy the topic position. Nevertheless, Spanish is more flexible regarding the position of the topic. All these aspects are illustrated with numerous examples offering possible equivalents between this language pair. Therefore, this study can help to fill in a gap in both the field of Chinese as a foreign language and didactics of translation La notion de thème a été largement étudiée, aussi bien en chinois et espagnol, mais pas dans sa structure thématique d'un point de vue contrastif. On a effectué une analyse à partir de la théorie de Loar (2011) et les résultats indiquent non seulement que le chinois utilise plus de constructions topicalisées que l'espagnol, mais possède également une plus grande variété de constructions de ce type, même s'il dispose de moins de souplesse quant à la position que peut occuper le thème dans la phrase. La possibilité d'employer des topicalisateurs, ainsi que les éléments qui peuvent constituer le sujet coïncident dans les deux langues. Tous ces aspects sont illustrés par de nombreux exemples, et des équivalences possibles sont proposées, de sorte que cette contribution peut combler une lacune dans le domaine de l'enseignement du chinois comme langue étrangère et de la traduction

When an oscillating line source is placed in front of a special mirror consisting of an array of flat uniformly spaced ferrite rods, half of the image disappeared at some frequency. We believe that this comes from the coupling to photonic states of the magnetic surface plasmon band. These states exhibit giant circulations that only go in one direction due to time reversal symmetry breaking. Possible applications of this "rectifying" reflection include a robust one-way waveguide, a 90 degree beam bender and a beam splitter, which are shown to work even in the deep subwavelength scale.