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In order to promote the accomplishment of the national carbon neutrality goal and enhance the international discourse power in the field of marine carbon sinks, this paper focused on high-resolution methods on the exploration of ocean carbon sink mechanism, covering biological and chemical detection methods and extensive applications. The results showed that marine refractory dissolved organic carbon pool played a significant role in carbon sink expansion, which put forward new challenges for high-resolution detection methods of dissolved organic carbon sink resources. Currently, high-resolution detection methods capable of tracking "fingerprint characteristics" mainly included flow cytometry and GeoChip functional detection, chemical detection methods, such as spectral and mass spectrometry as well as stable carbon isotope labeling technique that could realize the coupling between biological and chemical detection, were having crucial application prospects. With the stable carbon isotope labeling method as the link between biological traceability and chemical detection, all the technologies would have important application prospects.

In view of the problem of the GB/T 10414-2017 Synchronous belt drive car synchronous belt pulley standard does not provide the RU type and YU type pulley standard tool tooth profile parameter, the conjugate harmonic relationship between the pulley and tool tooth profile are studied. Firstly, the conjugate tool tooth surface of the pulley tooth profile is enveloped based on the meshing principle, and the discrete data of the envelope curve is mathematically fitted to determine the mathematical model of the cutter tooth profile. Secondly, through the second enveloping process of the cutter on the pulley, it is found that there is an undercut at the top of the tooth profile of the processed pulley tooth profile. Through the study of the mechanism of undercutting, the reason of singularity of cutter surface is revealed, and tooth profile model to eliminate the singular point of cutter tooth profile curve is proposed. The tooth profile error based on pulley is within the standard tolerance range, the cutter parameter is redesigned.

【Objective】The aim of this study was to elucidate the effect of associated chives on bacterial wilt and microecological characteristics of tomato rhizosphere, and to reveal the mechanism of reducing incidence of tomato bacterial wilt.【Method】Two treatments of tomato monoculture and tomatoes with chives were set for field experiments, and rhizosphere soils of diseased tomatoes in tomato monoculture treatment (QK), healthy tomatoes in tomato monoculture treatment (NBS) and tomatoes with chives treatment (BS) were collected. And the effects of companion chives on the micro-ecological characteristics of tomato rhizosphere were investigated by using 16S rDNA high-throughput sequencing and liquid chromatography-mass spectrometry.【Result】The results of field experiments showed that the average disease incidence of tomato bacterial wilt were 50.48% in tomato monoculture treatment and 31.43% in companion chives treatment. The control effect of companion chives on tomato bacterial wilt was 37.74%. According to the resulyts of 16S rDNA high-throughput sequencing, the relative abundance and diversity of bacterial communities in the rhizosphere soils of BS and NBS were significantly higher than those of QK. Compared with QK, the relative abundance of Ralstonia in the rhizosphere soils of BS and NBS was significantly lower than that of QK, and the relative abundance of Bacillus was higher than that of QK. Moreover, compared with NBS, the relative abundance of Ralstonia in the rhizosphere soil of BS was reduced, and the relative abundance of Bacillus was significantly enhanced. A total of 586 metabolites in tomato rhizosphere soil were identified by using LC-MS, including 320 positive ion mode metabolites and 266 negative ion mode metabolites. The functions of metabolites were annotated to metabolic pathways such as metabolism, genetic information processing and environmental information processing. Compared with NBS, the contents of valine, L-asparagine and citric acid in BS rhizosphere soil were significantly lower than those in NBS, and the contents of L-lysine, glutamic acid, D-glutamine and isoleucine in rhizosphere soil of BS were also lower than those of NBS, though, the difference was not significant.【Conclusion】The companion chives significantly reduced the disease incidence of tomato bacterial wilt in the field, and changed the bacterial community structure and metabolite contents in tomato rhizosphere soil.

Complete synthetic minimal media for Zygosaccharomyces rouxii growth were designed for high temperature (40 ℃, HTS) and high salt stress (18% NaCl, HSS) in this study, and the difference in the nutritional requirements of Z. rouxii cells under long-term adverse environmental conditions was analyzed. The differences in the metabolism and gene expression of organic acids, amino acids and sugars during the period from the growth adaptation stage to the early logarithmic stage were highlighted between HSS and HTS conditions. The results showed that Z. rouxii cells exposed to HSS needed more exogenous amino acids, vitamin and amino acid supplementation alleviated HTS-induced damage in yeast cells. The adversity transcription gene MSN4 and the hypertonic regulatory protein gene HOG1 responded to high salt, while the heat shock regulatory protein gene HSF1 and the superoxide dismutase gene SOD1 responded to high temperature. In summary, different strategies for organic acid, amino acid and sugar metabolism were adopted by Z. rouxii in response to HSS and HTS. This study deepens the understanding of the mechanism of temperature tolerance in salt-tolerant Z. rouxii, which will contribute to the development of new brewing yeast cells with tolerance to both high salt and temperature.