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Gradient Elastic–Plastic Properties of Expanded Austenite Layer in 316L Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 831-841页

作者： Yong Jiang Yang li Yun-Fei Jia Xian-cheng Zhang Jian-Ming Gong School of Mechanical and Power Engineering Nanjing University of TechnologyNanjing 211816China Key Laboratory of Design and Manufacture of Extreme Pressure Equipment Nanjing 211816Jiangsu ProvinceChina Key Laboratory of Pressure System and Safety MOESchool of Mechanical and Power EngineeringEast China Universityof Science and TechnologyShanghai 200237China

The gradient mechanical properties, variation of stress with strain and surface cracking behavior of expanded austenite developed on 316L austenitic stainless steel were investigated by nanoindentation tests, X-ray residual stress analysis and scanning electron microscope observation in four-point bending tests. The results show that the plastic properties of the carburizing layer including true initial yield strengths and strain hardening exponents increase significantly from substrate to surface, while the true elastic modulus just improves slightly. Due to the onset of plastic flow, the residual stresses are almost equivalent to the true initial yield strengths from surface to the depth of ～10 lm. The results of four-point bending tests show that surface stress increases linearly with the increase in strain until the strain reaches～1.0%, after that the plastic yield happens. The expanded austenite surface layer is brittle, and the cracks will be created at the strain of ～1.4%.The cracking stress is about～2.4 GPa.

关键词： Low-temperature gaseous carburization Expanded austenite Nanoindentation Gradient elastic-plastic properties Four-point bending

One-step synthesis of recoverable CuCo2S4 anode material for high-performance li-ion batteries

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 595-604页

作者： Tongzhou Lu Yongzheng Zhang Chun cheng Yanbin Wang Yongming Zhu Department of Applied Chemistry Harbin Institute of Technology at WeihaiWeihai 264209China

A facile one-step hydrothermal method has been adopted to directly synthesize the CuCo2S4 material on the surface of Ni *** to the relatively large specific surface area and wide pore size distribution,the CuCo2S4 material not only effectively increases the reactive area,but also accommodates more side reaction products to avoid the difficulty of mass *** evaluated as anode for li-ion batteries,the CuCo2S4 material exhibits excellent electrochemical performance including high discharge capacity,outstanding cyclic stability and good rate *** the current density of 200 mA·g^-1,the CuCo2S4 material shows an extremely high initial discharge capacity of 2510 mAh·g^-1,and the cycle numbers of the material even reach 83 times when the discharge capacity is reduced to 500 mAh·g^-***,the discharge capacity can reach 269 mAh·g^-1 at a current of 2000 mA·g^-*** importantly,when the current density comes back to 200 mA·g^-1,the discharge capacity could be recovered to 1436 mAh·g^-1,suggesting an excellent capacity recovery characteristics.

关键词： copper cobalt sulfide recoverability one-step hydrothermal method anode material li-ion battery

Discovering genes responsible for silk synthesis in Bombyx moriby piggyBac-based random insertional mutagenesis

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Insect Science 2019年第5期26卷 821-830页

作者： Xing-Bao Feng Zi-wen Zheng Xian Zhang Jun Gu Qi-li Feng li-Hua Huang Guangzhou Key Laboratory of Insect Development Regulation and Applied Research Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina

Silkworm mutants are valuable resources for both transgenic breeding and gene discovery. PiggyBac-based random insertional mutagenesis has been widely used in gene functional studies. In order to discover genes involved in silk synthesis, a piggyBac-based random insertional library was constructed using Bombyx mori, and the mutants with abnormal cocoon were particularly screened. By this means, a “thin cocoon” mutant was identified. This mutant revealed thinner cocoon shell and shorter posterior silk gland (PSG) compared with the wild type. The messenger RNA (mRNA) levels of all the three fibroin genes, including Fib-H, Fib-L and P25, were significantly down-regulated in the PSG of mutants. Four piggyBac insertion sites were identified in Aquaporin (AQP), Longitudinals lacking protein-like {Lola), Glutamyl aminopeptidase-like (GluAP) and Loc101744460. The mRNA levels of all the four genes were significantly altered in the silk gland of mutants. In particular, the mRNA amount of AQP, a gene responsible for the regulation of osmotic pressure, decreased dramatically immediately prior to the spinning stage in the anterior silk gland of mutants. The identification of the genes disrupted in the “thin cocoon” mutant in this study provided useful information for understanding silk production and transgenic breeding of silkworms in the future.

关键词： aquaporin Bombyx mori development mutant piggyBac silk gland

Analysis of DNA Methylation Level by Methylation-Sensitive Amplification Polymorphism in Half Smooth Tongue Sole(Cynoglossus semilaevis)Subjected to Salinity Stress

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Journal of Ocean University of China 2017年第2期16卷 269-278页

作者： li Siping HE Feng wen Haishen li Jifang SI Yufeng liU Mingyuan HE Huiwen HUANG Zhengju The Key Laboratory of Mariculture of Ministry of Education Fishery CollegeOcean University of ChinaQingdao 266003P.R.China

Increasingly arisen environmental constraints may contribute to heritable phenotypic variation including methylation changes,which can help the animals with development,growth and *** this study,we assessed the DNA methylation levels in three tissues(gonad,kidney and gill) of half smooth tongue sole under the salinity *** methylation-sensitive amplification polymorphism(MSAP) technique was applied to illustrate the regulation of epigenetic mechanism in environmental *** were subjected to 15 salinity treatment for 7 and 60 days,respectively.A total of 11259 fragments were amplified with 8 pairs of selective *** levels of methylated DNA in different tissues of females and males without salinity stress were analyzed,which were 32.76% and 47.32% in gonad;38.13% and 37.69% in kidney;37.58% and 34.96% in gill,*** addition,the significant difference was observed in gonad between females and males,indicating that discrepant regulation in gonadal development and differentiation may involve sex-related *** analysis showed that total and hemi-methylation were significantly decreased under 15 salinity for 7 days,probably resulting in up-regulating salt-tolerance genes expression to adjust salt *** the adjustment for 60 days,total and hemi-methylation prominently went back to its normal levels to obtain ***,full methylation levels were steady along with salinity stress to maintain the stability of gene ***,the data showed that gonads in females and gills in males were superior in *** a result,DNA methylation regulates tissue-specific epiloci,and may respond to salinity stress by regulating gene expression to maintain animal survival and activity.

关键词： DNA methylation diversity half smooth tongue sole salinity stress MSAP

light Scattering Microscopy of Surface and Its Computational Simulation

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Chinese Physics Letters 1999年第6期16卷 397-399页

作者： cheng Chuan-fu liU De-li QI Dong-ping Department of Physics Shandong Normal UniversityJi'nan 250014

The light scattering microscopy is proposed,which reconstructs the height distribution function of a random surface from the speckle intensity of the scattered light *** the computational simulation,we generated the random surfaces of Gaussian correlation and the speckle intensities,and reconstructed the surfaces by Gerchberg-Saxton(G-S)and modified G-S *** simulation proves this microscopy works well.

关键词： wave. speckle random

Patterns of human-wildlife conflict and compensation practices around Daxueshan Nature Reserve, China

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Zoological Research 2018年第6期39卷 406-412页

作者： cheng Huang Xue-You li liu-Jun Shi Xue-Long Jiang Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China Kunming College of life Sciences University of Chinese Academy of Sciences Kunming Yunnan 650223 China Daxueshan Nature Reserve Yongde Yunnan 677600 China

Understanding the spatial patterns of human-wildlife conflict is essential to inform management decisions to encourage coexistence, but it is constrained by the lack of spatially-explicit data. We collected spatially-implicit data of human-wildlife conflicts from 2009-2015 around Daxueshan Nature Reserve, Yunnan, China, and investigated the patterns and drivers of these conflicts. A questionnaire was also designed to capture local resident attitudes toward insurance-based compensation for the losses caused by targeted wildlife. We found that the Asiatic black bear （Ursus thibetanus） was the most conflict-prone animal around the reserve, followed by the rhesus macaque （Macaca mulatta） and Southeast Asian sambar （Cervus equinus）. Conflicts were unevenly distributed among seasons, villages, and communities, with several grids identified as conflict hotspots. Poisson models revealed that human-bear conflicts were negatively related to distance to the reserve and proportion of forest, but positively correlated to the proportion of cropland. Binomial models showed that communities affected by crop depredation were positively correlated with the proportion of cropland and negatively correlated with distance to the reserve, whereas communities affected by livestock depredation were negatively correlated with the proportion of cropland. The insurance-based scheme has compensated over 90% of losses, to the satisfaction of 90.6% of respondents. Our results suggest that human-bear conflict could be potentially reduced by eliminating food crops near the reserve boundary and livestock grazing at conflict *** addition, the insurance-based scheme could be replicated at a broader scale with improvement in loss assessment.

关键词： Human-wildlife conflict Asiatic black bear Spatial heterogeneity Insurance scheme Daxueshan Nature Reserve

Soil Carbon Sequestration Potential as Affected by Management Practices in Northern China:A Simulation Study

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Pedosphere 2014年第4期24卷 529-543页

作者： WANG Guo-cheng WANG En-li HUANG Yao XU Jing-Jing State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of Sciences CSIRO Land & Water Black MountainCanberraACT 2601(Australia) State Key Laboratory of Vegetation and Environmental Change(LVEC) Institute of BotanyChinese Academy of Sciences

Soil has been identified as a possible carbon （C） sink for sequestering atmospheric carbon dioxide （CO2）. However, soil organic carbon （SOC） dynamics in agro-ecosystems is affected by complex interactions of various factors including climate, soil and agricultural management practices, which hinders our understanding of the underlying mechanisms. The objectives of this study were to use the Agricultural Production Systems simulator （APSIM） model to simulate the long-term SOC dynamics under different management practices at four long-term experimental sites, Zhengzhou and Xuzhou with double cropping systems and Gongzhuling and Urtimqi with single cropping systems, located in northern China. Firstly, the model was calibrated using information from the sites and literature, and its performance to predict crop growth and SOC dynamics was examined. The calibrated model was then used to assess the impacts of different management practices, including fertilizer application, irrigation, and residue retention, on C dynamics in the top 30 cm of the soil by scenario modelling. Results indicate a significant SOC sequestration potential through improved management practices of nitrogen （N） fertilizer application, stubble retention, and irrigation. Optimal N fertilization （Nopt） and 100% stubble retention （R100） increased SOC by about 11.2%, 208.29%, and 283.67% under irrigation at Gongzhuling, Zhengzhou, and Xuzhou, respectively. Soil organic carbon decreased rapidly at lJriimqi under irrigation, which was due to the enhanced decomposition by increased soil moisture. Under rainfed condition, SOC remained at a higher level. The combination of Nopt and R100 increased SOC by about 0.46% under rainfed condition at /Jr/imqi. Generally, agricultural soils with double cropping systems （Zhengzhou and Xuzhou） showed a greater potential to sequester C than those with single cropping systems （Gongzhuling and Urumqi）.

关键词： agro-ecosystems APSIM model fertilizer application irrigation residue retention scenario analysis soil organic carbon

Huangqin Decoction Attenuates DSS-Induced Mucosal Damage and Promotes Epithelial Repair via Inhibiting TNF-α-Induced NF-κB Activation

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Chinese Journal of Integrative Medicine 2022年第2期28卷 124-129页

作者： GU li-mei li Hui XIA Jun-quan PAN cheng-yu GU Chao TIAN Yao-zhou Gastroenterology Department Affiliated Hospital of Integrated Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing(210028)China Gastroenterology Department Jiangsu Province Hospital on Integration of Chinese and Western MedicineNanjing(210028)China Jiangsu Province Academy of Traditional Chinese Medicine Nanjing(210028)China

Objective:To investigate the protective effect of Chinese herbal formula Huangqin Decoction(HQD)on ulcerative colitis mouse model induced by dextran sulphate sodium(DSS)and human intestinal epithelial cell injury induced by tumour necrosis factor-α(TNF-α).Methods:In vivo,30 male C57BL/6 mice were divided into 5 groups using a random number table(n=6 per group),including control,DSS,5-aminosalicylic acid(5-ASA),HQD low-(HQD-L)and high-dose(HQD-H)*** colitis mouse model was established by 3%(w/v)DSS water for 5 ***,mice in the HQD-L,HQD-H and 5-ASA groups were administrated with 100,200 mg/kg HQD or 100 mg/kg 5-ASA,respectively,once daily by *** 9 days of administration,the body weight,disease activity index(DAI)score and colon length of mice were measured,the pathological changes of colons were analyzed by hematoxylin-eosin staining(HE)staining,and the levels of serum interleukin(IL)-6,IL-1βand TNF-αwere measured by enzyme linked immunosorbent *** vitro,the human colon epithelial normal cells(FHC cells)were exposed to HQD(0.6 mg/mL)for 12 h and then treated with TNF-α(10 ng/mL)for 24 *** tight junction(TJ)protein expression levels of Claudin-4 and Occludin,and the protein phosphorylation levels of p65 and inhibitor of nuclear factor kappaB(NF-κB)-α(IκBα)were measured by Western ***:In vivo,compared with the DSS group,HQD-H treatment attenuated the weight loss and reduced DAI score of mice on the 8th day(Pliorated the colon shortening in the DSS-induced colitis mice(Plitis mice,and the histological scores of HQD-H and 5-ASA groups were significantly decreased compared with the DSS group(P<0.05).Meanwhile,HQD-H and 5-ASA significantly decreased the serum IL-1β,IL-6 and TNF-αlevels of mice(P<0.05).In vitro experiments showed that HQD up-regulated Occludin and Claudin-4 protein expressions and inhibited p-p65 and p-IκBαlevel

关键词： Huangqin Decoction ulcerative colitis tumour necrosis factor-α nuclear factor kappaB pathway tight conjunction protein Chinese medicine

Keyword Query over Error-Tolerant Knowledge Bases

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Journal of Computer Science & Technology 2016年第4期31卷 702-719页

作者： Yu-Rong cheng Ye Yuan Jia-Yu li Lei Chen Guo-Ren Wang College of Computer Science and Engineering Northeastern University Shenyang 110819 China College of Information Science and Engineering Northeastern University Shenyang 110819 China Department of Computer Science and Engineering Hong Kong University of Science and Technology Hong Kong China

With more and more knowledge provided by WWW, querying and mining the knowledge bases have attracted much research attention. Among all the queries over knowledge bases, which are usually modelled as graphs, a keyword query is the most widely used one. Although the problem of keyword query over graphs has been deeply studied for years, knowledge bases, as special error-tolerant graphs, lead to the results of the traditional defined keyword queries out of users＇ satisfaction. Thus, in this paper, we define a new keyword query, called confident r-clique, specific for knowledge bases based on the r-clique definition for keyword query on general graphs, which has been proved to be the best one. However, as we prove in the paper, finding the confident r-cliques is #P-hard. We propose a filtering-and-verification framework to improve the search efficiency. In the filtering phase, we develop the tightest upper bound of the confident r-clique, and design an index together with its search algorithm, which suits the large scale of knowledge bases well. In the verification phase, we develop an efficient sampling method to verify the final answers from the candidates remaining in the filtering phase. Extensive experiments demonstrate that the results derived from our new definition satisfy the users＇ requirement better compared with the traditional r-clique definition, and our algorithms are efficient.

关键词： keyword query error-tolerant knowledge base index