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The selective catalytic reduction of NO by CO (CO-SCR) are frequently catalyzed by spinel due to its exceptional stability and redox capabilities. In this research, a ternary metal-based inverse spinel catalyst Cu 0.67 Mn 0.33 Fe 2 O 4 was synthesized utilizing the glycerol self-templating technique. Some Fe3+ (Fe3+ Td) sites are transferred to vacant octahedral sites through the occupancy of tetrahedral sites by Mn species. Mn3+ (Mn3+ Td) sites synergistically interact with Cu2+ and Fe3+ ions on the octahedral sites to promote charge transfer, producing numerous oxygen-defective and highly mobile oxygen species and constructing Cu+-O v -Fe2+ active sites on the surface. Various characterizations demonstrated that Cu+-O v -Fe2+ has greater catalytic activity, resistance to alkali metals, and water toxicity than the Cu2+-O v -Fe2+ active site of CuFe 2 O 4. In situ DRIFTS further revealed the reaction mechanism of the ternary metal-based inverse spinel catalyst, and this study provides novel perspectives on the development of Cu-based catalysts for CO-SCR. [Display omitted] • The introduction of Mn metal ions to partially occupy Fe3+ T d during the synthesis modulated the charge distribution of CuFe 2 O 4. • Construction of Cu+-O v -Fe2+ on the surface by site-specific occupancy to improve the conversion of NO x and resistance to water and alkali metal poisoning in practical applications. • Probing the catalytic activity mechanism of ternary CuMnFe inverse spinel and analyzing the cause of alkali poisoning by in situ DRIFTS. [ABSTRACT FROM AUTHOR]

• The second syllables of nouns are longer than those of verbs. • Both syllables of nouns are higher and greater than those of verbs. • Information load determines phonetic differences between nouns and verbs. • Number of syllables impacts the duration of nouns and verbs. • The phonetic differences between nouns and verbs stem from the two word classes. This study investigates how word categories, namely noun and verb, influence acoustic realizations (duration, F0, intensity) in Standard Mandarin Chinese, a language having phonemically distinctive tones and a simple morphological system. Noun-verb ambiguous words were selected and presented in the final positions of typical syntactic contexts in order to avoid the interference of prosodic boundary, syntactic complexity, contextual predictability, tonal environment, F0 range and syllable properties (consonant, vowel, tone, syllable length). Linear mixed models were fitted to duration, and generative additive mixed models were fitted to F0 and intensity. The results showed that phonetic differences between nouns and verbs were still evident in duration, F0 and intensity after lexical frequency, speech rate and some other related factors were taken into consideration in the models. The second syllables of nouns were longer than those of verbs, and both syllables of nouns were higher in F0 and greater in intensity than those of verbs. Since the prosodic boundary, frequency and other factors were controlled for, the phonetic differences between nouns and verbs might be attributed to their differences in information load and number of syllables. This study provided evidence that phonetic differences between nouns and verbs might be driven by the grammatical classes themselves and is not an epiphenomenon of other processes. [ABSTRACT FROM AUTHOR]

Benefiting from the closed wellbore space for heat-carrying fluid circulation, the wellbore self-circulation technology can effectively avoid the problems of wellbore scaling, corrosion, formation deficit, and reinjection capacity decline in the traditional geothermal mining technology. However, its applicability and how to enhance the heat extraction rate still need to be further clarified, especially in the medium-low temperature geothermal reservoirs. In this study, a comprehensive simulation model on the heat extraction from a porous medium-low temperature geothermal reservoir in Xining Basin, China by self-circulation wellbore was established to study the heat extraction capacity and influencing factors. Different methods to improve the heat extraction rate of self-circulation wellbore were investigated, compared and discussed. The results show that the heat extraction rate of the self-circulation wellbore is relatively low. Under reasonable cycling, wellbore and reservoir conditions, the heat extraction rate can reach 20–100 kW, and the heat extraction range is mainly within 50 m around the well. The injection temperature, geothermal water seepage, and formation lithology have significant effects on heat extraction rate. The horizontal well, intermittent self-circulation, open self-circulation, and cross-layer pumping and reinjection can all enhance the heat extraction capacity of the self-circulation wellbore but with different disadvantages. Comprehensively considering the low capital cost, slight scaling and corrosion risk and good heat extraction performance, the self-circulation of open wellbore is the best way to enhance the heat extraction rate in a medium-low temperature geothermal reservoir. [ABSTRACT FROM AUTHOR]