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Heat Treatment Effect on Microstructure, Hardness and Wear Resistance of Cr26 White Cast Iron

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 140-147页

作者： ZHOU Shaoping SHEN yehui ZHANG Hao CHEN Dequan Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and Technology Shanghai First Fluid Machinery Co.Ltd

High chromium cast iron（HCCI） is taken as material of coal water slurry pump impeller, but it is susceptible to produce serious abrasive wear and erosion wear because of souring of hard coal particles. The research on optimization of heat treatments to improve abrasive wear properties of HCCI is insufficient, so effect of heat treatments on the microstructure, hardness, toughness, and wear resistance of Cr26 HCCI is investigated to determine the optimal heat treatment process for HCCI. A series of heat treatments are employed. The microstructures of HCCI specimens are examined by using optical microscopy and scanning electron microscopy. The hardness and impact fracture toughness of as-cast and heat treated specimens are measured. The wear tests are assessed by a Type M200 ring-on block wear tester. The results show the following： With increase of the quenching temperature from 950 ℃ to 1050 ℃, the hardness of Cr26 HCCI increased to a certain value, kept for a time and then decreased. The optimal heat treatment process is 2 h quenching treatment at 1000 ℃, followed by a subsequent 2 h tempering at 400 ℃. The hardness of HCCI is related to the precipitation and redissolution of secondary carbides in the process of heat treatment. The subsequent tempering treatment would result in a slight decrease of hardness but increase of toughness. The wear resistance is much related to the ＂supporting＂ effect of the matrix and the ＂protective＂ effect of the hard carbide embedded in the matrix, and the wear resistance is further dependent on the hardness and the toughness of the matrix. This research can provide an important insight on developing an optimized heat treatment method to improve the wear resistance of HCCI.

关键词： Cr26 white cast iron heat treatment microstructure hardness wear resistance

A new species of Cymbasoma Thompson, 1888(Copepoda: Monstrilloida) from the Fujian coast, China

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Journal of Oceanology and Limnology 2019年第5期37卷 1708-1713页

作者： LIAN Xiping TAN yehui Marine Biodiversity Collections of South China Sea / Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China

A new monstrilloid copepod species, Cymbasoma cheni sp. nov., from Meizhou Bay (an embayment in Fujian Province, southeastern China) is described and illustrated. The diagnostic character of the new species is the structure and armature of the fi fth leg, which is represented by a single lobe armed with three naked setae subequal in length. The new species closely resembles Cymbasoma bowmani Suárez- Morales and Gasca, 1998 in the structure of the fi fth legs, and the body proportions, including total body length, and relative lengths of the cephalothorax and the genital double somite. However, Cymbasoma cheni sp. nov. is distinguished by lack of cuticular ornamentation on the cephalothorax, the position of the oral papilla, and the structure of the fi fth leg with three naked setae. Although the structure of the fi fth legs is similar in Cymbasoma cheni sp. nov. and Cymbasoma quintanarooense (Suárez-Morales, 1994), the new species can be easily distinguished from Cymbasoma quintanarooense by the relative length of the antennule, diff erences in the genital double-somite and the ovigerous spines, and the shape of ocelli. This is the sixth record of this genus from China seas.

关键词： copepoda Monstrilloida Cymbasoma new species Fujian Coast

Coral reef ecological pump for gathering and retaining nutrients and exporting carbon:a review and perspectives

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Acta Oceanologica Sinica 2023年第6期42卷 1-15页

作者： Linbin Zhou yehui Tan Liangmin Huang CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Provincial Key Laboratory of Applied Marine Biology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China University of Chinese Academy of Sciences Beijing 100049China

How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef *** evidence shows that similar to water in an oasis in the desert,there are stable nutrient supplies to coral reefs in oligotrophic ***,with emphasis on the fluxes of organic matter,we summarize at the ecosystem level(1)the multiple input pathways of external nutrients,(2)the storage of nutrients in reef organisms,(3)the efficient retaining and recycling of dissolved and particulate organic matter within coral reef ecosystems,(4)the distinctly high phytoplankton productivity and biomass inside and near oceanic coral reefs,and(5)the export of reef-related organic carbon to adjacent open *** properties enable coral reefs to function as ecological“pumps”for gathering nutrients across ecosystems and space,retaining and recycling nutrients within the ecosystem,supporting high phytoplankton productivity,and exporting organic carbon to adjacent open ***,the high phytoplankton productivity and biomass make waters around coral reefs potential hotspots of carbon export to ocean depths via the biological *** demonstrate that organic carbon influx is vital for coral reef ecosystems’carbon budget and carbon *** concept of the coral reef ecological pump provides a framework to improve the understanding of the functioning of the coral reef ecosystem and its responses to *** of the coral reef ecological pump in coral reef studies are discussed in changing oceans driven by human activities and global change in the Anthropocene.

关键词： Darwin’s Paradox coral reef nutrients coral reef ecological pump carbon export ocean carbon cycle

Engineered Bacillus subtilis alleviates intestinal oxidative injury through Nrf2-Keap1 pathway in enterotoxigenic Escherichia coli(ETEC) K88-infected piglet

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第6期24卷 496-509页

作者： Chaoyue WEN hong ZHANG Qiuping GUO yehui DUAN Sisi CHEN Mengmeng HAN Fengna LI Mingliang JIN Yizhen WANG Institute of Feed Science Key Laboratory of Animal Feed and Nutrition of Zhejiang ProvinceKey Laboratory of Molecular Animal NutritionMinistry of EducationKey Laboratory of Animal Nutrition and Feed Science in Eastern ChinaMinistry of AgricultureCollege of Animal SciencesZhejiang UniversityHangzhou 310058China Hunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic Process CAS Key Laboratory of Agro-Ecological Processes in Subtropical RegionNational Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry ProductionInstitute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China College of Advanced Agricultural Science University of Chinese Academy of SciencesBejing 100039China

Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating *** this study,we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32(WB800-KR32)using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2(Nrf2)-Kelch-like ECH-associated protein 1(Keap1)pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli(ETEC)K88 in weaned ***-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal *** feed of the control group(CON)was infused with normal sterilized saline;meanwhile,the ETEC,ETEC+WB800,and ETEC+WB800-KR32 groups were orally administered normal sterilized saline,5×10^(10)CFU(CFU:colony forming units)WB800,and 5×10^(10)CFU WB800-KR32,respectively,on Days 1-14 and all infused with ETEC K881×10^(10)CFU on Days *** results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance,improved the mucosal activity of antioxidant enzyme(catalase(CAT),superoxide dismutase(SOD),and glutathione peroxidase(GPx))and decreased the content of malondialdehyde(MDA).More importantly,WB800-KR32 downregulated genes involved in antioxidant defense(GPx and SOD1).Interestingly,WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ***800-KR32 markedly changed the richness estimators(Ace and Chao)of gut microbiota and increased the abundance of Eubacterium_rectale_ATCC_33656 in the *** results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway,providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.

关键词： Engineered probiotics Intestine Oxidative injury Weaned piglets Nuclear factor-E2-related factor 2(Nrf2)-Kelch-like ECH-associated protein 1(Keap1)pathway

Diurnal variability of the planetary boundary layer height estimated from radiosonde data

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Earth and Planetary Physics 2020年第5期4卷 479-492页

作者： Jie Gu yehui Zhang Na Yang Rui Wang School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China

Diurnal variations in the planetary boundary layer height(PBLH)at different latitudes over different surface characteristics are described,based on 45 years(1973−2017)of radiosonde *** PBLH is determined from the radiosonde data by the bulk Richardson number(BRN)method and verified by the parcel method and the potential temperature gradient *** general,the BRN method is able to represent the height of the convective boundary layer(BL)and neutral residual layer cases but has relatively large uncertainty in the stable BL *** diurnal cycle of the PBLH over land is quite different from the cycle over ocean,as are their seasonal *** stations over land,the PBLH shows an apparent diurnal cycle,with a distinct maximum around 15:00 LT,and seasonal variation,with higher values in *** with the PBLH over land,over oceans the PBLH diurnal cycles are quite mild,the PBLHs are much lower,and the seasonal changes are less *** seasonal variations in the median PBLH diurnal cycle are positively correlated with the near-surface temperature and negatively correlated with the near-surface relative ***,although at most latitudes the daytime PBLH exhibits,over these 45 years,a statistically significant increasing trend at most hours between 12:00 LT and 18:00 LT over both land and ocean,there is no significant trend over either land or ocean in the nighttime PBLH for almost all the studied latitudes.

关键词： planetary boundary layer height diurnal cycle radiosonde

Striking taxonomic differences in summer zooplankton in the northern South China Sea: implication of an extreme cold anomaly

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Acta Oceanologica Sinica 2017年第10期36卷 87-96页

作者： LIAN Xiping TAN yehui HUANG Liangmin ZHOU Linbin Key Laboratory of Marine Bio-resource Sustainable Utilization (LMB) South China Sea Institute of OceanologyChinese Academy of Sciences

An extreme persistent cold anomaly was prevailing in the South China Sea in February 2008. In order to understand the effect of the cold anomaly on zooplankton community, the zooplankton composition, abundance and biomass were analyzed in the northern South China Sea in August 2007 and August 2008. A total of 467 zooplankton species representing 16 groups were identified, with 275 species in August 2007 and 351 in August2008. Copepods were the most dominant zooplankton group in the study area. Compared with 2007, a dramatic decline was observed in the abundance of four dominant copepod species： Subeucalanus subcrassus, Temora discaudata, Nannocalanus minor and Temora turbinata in 2008. Moreover, zooplankton abundance declined from 133.37 ind./m^3 in August 2007 to 75.49 ind./m^3 in August 2008. In contrast, the abundance of medusa, such as Diphyes chamissonis, and tunicate, such as Doliolum denticulatum and Dolioletta gegenbauri, increased during the same season. Cluster analysis showed that there was a difference in zooplankton community structure between the two years. These variations in zooplankton communities were indicative of an anomalous oceanographic condition along with the extreme cold event in 2008.

关键词： zooplankton community cold anomaly northern South China Sea

NLRP3炎性小体在脊髓损伤后小胶质细胞中的作用

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中国组织工程研究 2025年第13期29卷 2849-2860页

作者：周文洋廖烨晖田明昊何宝强钟德君西南医科大学附属医院骨科四川省泸州市646000

背景:NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)炎性小体与脊髓损伤后的神经炎症密切相关,小胶质细胞极化和焦亡在其中发挥关键作用,靶向调控NLRP3有利于诱导小胶质细胞... 详细信息

背景:NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)炎性小体与脊髓损伤后的神经炎症密切相关,小胶质细胞极化和焦亡在其中发挥关键作用,靶向调控NLRP3有利于诱导小胶质细胞从M1促炎表型向M2抗炎表型极化和调节小胶质细胞焦亡,是一个有前景的治疗策略。目的:归纳NLRP3炎性小体在脊髓损伤后小胶质细胞中作用的分子机制以及治疗策略的研究进展。方法:检索PubMed、Web of Science和中国知网数据库,英文检索词为“spinal cord injury,NLRP3,microglia,polarization,pyroptosis”,中文检索词为“脊髓损伤,NLRP3,小胶质细胞,极化,焦亡,炎症”,按纳入和排除标准共纳入79篇文献进行总结。结果与结论:①目前,关于脊髓损伤复杂的发病机制尚未有统一定论,大量研究表明脊髓损伤与炎症因子和信号通路关系密切,以NLRP3炎性小体作为其发病机制和治疗突破口的相关研究也是当前的热点。②NLRP3炎性小体在脊髓损伤后的炎症反应、氧化应激和神经元恢复等起到关键作用。③小胶质细胞是脑和脊髓中的免疫细胞,是继发性脊髓损伤最重要的调节因子,脊髓损伤后小胶质细胞对内部环境作出调整,主要表现为极化及焦亡,产生大量炎症因子,阻碍脊髓损伤的神经再生和功能恢复,通过调控小胶质细胞表型变化,是治疗脊髓损伤的另一个关键因素。④NLRP3炎性小体与小胶质细胞密切相关,脊髓损伤后NLRP3炎性小体主要在小胶质细胞中表达,其会促进小胶质细胞向M1极化和促进促裂解蛋白D的产生,进一步破坏神经稳态,从而加重脊髓损伤的进展。⑤许多分子参与NLRP3炎性小体调控小胶质细胞,其中核转录因子κB及MAPK信号通路促进NLRP3炎性小体表达,其他信号通路抑制该炎性小体表达。⑥目前有大量的外源性分子及药物调控NLRP3炎性小体,临床应用前景广泛,已有相关药物处于临床试验阶段并取得良好疗效,如NLRP3特异性抑制剂MCC950,但如何精准控制靶向递送、减少对其他组织器官影响等关键问题亟需解决,随着研究的深入,未来有望在脊髓损伤治疗方式上作出新的突破。

关键词：脊髓损伤 NLRP3 小胶质细胞极化焦亡炎症非编码RNA 中药活性成分干细胞特异性抑制剂

STRESS ANALYSIS OF CANNED HOT FORGING SPECIMEN OF TiAl INTERMETALLIC COMPOUND

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中国有色金属学会会刊：英文版 1997年第2期7卷 92-95页

作者： Rao, Qiuhua He, yehui Huang, Baiyun Liu, Wensheng Central South Univ of Technology Changsha China

ＳＴＲＥＳＳＡＮＡＬＹＳＩＳＯＦＣＡＮＮＥＤＨＯＴＦＯＲＧＩＮＧＳＰＥＣＩＭＥＮＯＦＴｉＡｌＩＮＴＥＲＭＥＴＡＬＬＩＣＣＯＭＰＯＵＮＤ①ＲａｏＱｉｕｈｕａＤｅｐａｒｔｍｅｎｔｏｆＡｒｃｈｉｔｅｃｔｕｒｅＥｎｇｉｎｅｒ... 详细信息

ＳＴＲＥＳＳＡＮＡＬＹＳＩＳＯＦＣＡＮＮＥＤＨＯＴＦＯＲＧＩＮＧＳＰＥＣＩＭＥＮＯＦＴｉＡｌＩＮＴＥＲＭＥＴＡＬＬＩＣＣＯＭＰＯＵＮＤ①ＲａｏＱｉｕｈｕａＤｅｐａｒｔｍｅｎｔｏｆＡｒｃｈｉｔｅｃｔｕｒｅＥｎｇｉｎｅｒｉｎｇ，ＨｅＹｅｈｕｉ，Ｈｕａｎｇ...

关键词： stress analysis canned hot forging TiAl intermetallic compound

Topology tracking of dynamic UAV wireless networks

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Chinese Journal of Aeronautics 2022年第11期35卷 322-335页

作者： yehui SONG Guoru DING Jiachen SUN Jinghua LI Yitao XU College of Communications Engineering Army Engineering University of PLANanjing 210007China

Wireless network is the communication foundation that supports the intelligentization of Unmanned Aerial Vehicle(UAV) swarm. The topology of UAV communication network is the key to understanding and analyzing the behavior of UAV swarm, thus supporting the further prediction of UAV operations. However, the UAV swarm network topology varies over time due to the high mobility and diversified mission requirements of UAVs. Therefore, it is important but challenging to research dynamic topology inference for tracking the topology changes of the UAV network,especially in non-cooperative manner. In this paper, we study the problem of inferring UAV swarm network topology based on external observations, and propose a dynamic topology inference method. First, we establish a sensing framework for acquiring the communication behavior of the target network over time. Then, we expand the multi-dimensional dynamic Hawkes process to model the communication event sequence in a dynamic wireless network. Finally, combining the sliding time window mechanism, the maximum weighted likelihood estimation is applied to inferring the network topology. Extensive simulation results demonstrate the effectiveness of the proposed method.

关键词： Dynamic topology inference Event detection Hawkes process UAV swarm Wireless networks