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Effect of Nanoscale Cu-Riched Clusters on Strength and Impact Toughness in a Tempered Cu-Bearing HSLA Steel

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Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 537-550页

作者： Yubin du Xiaofeng Hu yuanyuan Song Yangpeng Zhang Lijian Rong CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The effect of Cu-riched clusters on strength and impact toughness in a tempered Cu-bearing high-strength low-alloy(HSLA)steel is investigated. With increasing the tempering temperature, it is found that the yield strength increases firstly, achieving the maximum value(~ 1053 MPa) at the tempering temperature of 450 ℃, and then decreases significantly with the rise of tempering temperature. The tempering temperature-dependent yield strength is closely related to the precipitation of Cu-riched clusters. When tempering at 450 ℃, the peak strength will be reached as the nanoscale Cu-riched clusters with small size and high number density will cause a strong precipitation strengthening(~ 492 MPa) due to the dislocation shearing mechanism. However, the Cu-riched clusters will coarsen with further increasing tempering temperature, resulting in obvious decrement of yield strength owing to the dislocation bypassing mechanism. Compared with the yield strength,the variation in impact energy displays an inverse tendency and the impact energy is only 7 J for the sample tempered at 450 ℃. The fracture mode can be well explained by the competition between the cleavage fracture strength( σ F) and “yield strength”( σ Y). Although transgranular cleavage fracture can be found in samples tempered at 450 and 550 °C, the crack propagation along the lath boundaries is prevented in the sample tempered at 550 ℃. The reason is that the number density of Cu-riched clusters at lath boundaries decreases and the segregation of Mo element at the lath boundaries is induced,which will increase the bonding energy.

关键词： High-strength low-alloy(HSLA)steel Cu-riched cluster Strengthening mechanism Lath boundary Impact energy

Increased Mortality Risks from a Spectrum of Causes of Tropical Cyclone Exposure — China, 2013–2018

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China CDC weekly 2023年第6期5卷 119-124,I0001-I0007页

作者： yuanyuan Liu Meilin Yan Hang du Qinghua Sun G.Brooke Anderson Tiantian Li China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina School of Ecology and Environment Beijing Technology and Business UniversityBeijingChina Department of Environmental&Radiological Health Sciences Colorado State UniversityFort CollinsCOUSA

What is already known about this topic?Tropical cyclone(TC)has a substantial and adverse impact on non-accidental mortality.However,whether heterogeneity exists when examining deaths from subcauses and how TC impacts non-accidental mortality in the short term remain unclear.What is added by this report?This study found substantial associations at lag 0 between TC exposure and circulatory and respiratory mortality.TC exposures were associated with increased risks for several mortality sub-causes at lag 0 day,including ischemic heart disease,myocardial infarction,cardiac arrest,cerebrovascular disease,stroke,chronic obstructive pulmonary disease,and Parkinson’s disease.What are the implications for public health practice?This finding suggests an urgent need to expand the public health focus of natural disaster management to include non-accidental mortality and sub-causes.

关键词： mortality disaster Tropical

Numerical Investigation on the Heat Transfer Characteristics of Supercritical Water in a Non-Uniformly Heated Tube for a Supercritical CFB Boiler

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Journal of Thermal Science 2023年第5期32卷 1807-1818页

作者： du Xiaocheng SONG yuanyuan XIANG Yuxuan ZHOU Yanjun WANG Aoyu YANG Dong State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

In this paper,a numerical model was built by ANSYS FLUENT to investigate the heat transfer performances of supercritical water in a circumferential non-uniformly heated vertical tube.The Shear Stress Transport(SST)k-ωmodel was adopted for describing turbulence.The operating parameters are chosen according to a 660 MW ultra-supercritical CFB boiler.The heat transfer performances under different operating parameters,such as boiler load,flow direction and heat flux distribution are analyzed.The temperature and heat flux on inner wall varies along the circumference and show symmetric distributions.The overall heat transfer performances at each cross section are better than the local heat transfer performance of midpoint of heating side.Flow direction has a great influence on heat transfer performance;it changes the radial distribution of axial velocity and then affects the turbulence distribution.Therefore,upward flow condition shows a better heat transfer performance.Smaller heat flux improves both the overall and local heat transfer performances.Reducing the heat flux area is not conducive to the overall heat transfer,but does not affect the local heat transfer at the midpoint of heating side.Finally,a new correlation is fitted based on the simulated results of supercritical water heat transfer with circumferential non-uniform heat flux distributions.

关键词： supercritical CFB boiler circumferential non-uniform heat flux numerical simulation heat transfer correlation

Biological Analysis and Response to Low Phosphate Stress of Phosphate Transporter Family 1 (PHT1) Genes in Solanum tuberosum L.

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Phyton-International Journal of Experimental Botany 2023年第8期92卷 2325-2348页

作者： Yangyang du yuanyuan Bao Lu Zheng Qinglong Tian Xinyong Zhang Key Laboratory of Crop Germplasm Innovation and Sustainable Utilization Collage of Agronomy and BiotechnologyYunnan Agricultural UniversityKunming650201China Laboratory of Fruit and Vegetable Preservation and Processing College of Food Science and TechnologyYunnan Agricultural UniversityKunming650201China

Inorganic phosphate(Pi)is one of the main nutrients necessary for plant growth.Phosphate transporters mediate the acquisition,transport and recycling of phosphate,which is essential for plant growth and development.Although PHT1 has been reported in many plants at home and abroad,it is rarely studied in potato.Therefore,it is of great signiﬁcance to study the PHT1 family members in order to understand the molecular response mechanism of potato in low phosphate state.In this study,a total of 6 potato PHT1 genes were identiﬁed and isolated.It was found that after the expression of different members of potato PHT1 gene,there were certain differences in amino acids and proteins,and the transmembrane domains ranged from 6 to 12.The difference in the secondary and tertiary protein structure of potato PHT1 also led to a difference in protein morphology.In addition,the expression of the PHT1 gene in potato increased obviously during 3~9 h of Pi deﬁciency stress.Overall,the expression levels of different genes in roots,stems and leaves are distinctly different,but the expression levels of the StPHT1;6 and StPHT1;10 genes are very high in roots,stems and leaves,indicating that these two genes may participate in the absorption of Pi in potato and play a role in Pi translocation.These two genes play a major role in the regulation of expression under short-term Pi deﬁciency stress.Our results provide an important reference for further understanding the evolution and function of potato phosphate transporters,and have important signiﬁcance for improving the ability of potato to tolerate low Pi.

关键词： Potato phosphate transporter gene short-term phosphate-deficiency stress biological analysis

The 35S promoter-driven mDII auxin control sensor is uniformly distributed in leaf primordia

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Journal of Integrative Plant Biology 2019年第11期61卷 1114-1120页

作者： Chunmei Guan Fei du yuanyuan Xiong Yuling Jiao State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

The DII auxin sensor has been an invaluable tool for mapping the spatiotemporal auxin response and distribution in the model plant Arabidopsis thaliana.The DII sensor and the m DII control sensor are driven by the wid... 详细信息

关键词： constitutive auxin sensor

Origin of Halite in the Lanping–Simao Basin,Southeastern Tibetan Plateau,China:Evidence from Sr and Cl Isotopes

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2028-2039页

作者： du Shaorong ZHENG Mianping LÜyuanyuan ZHANG Yongsheng ZHANG Xuefei MIAO Zhongying LI Mingming MLR Key Laboratory of Saline Lake Resources and Environments Institute of Mineral ResourcesChinese Academy of Geological Sciences(CAGS)Beijing 100037China College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China

The Lanping−Simao Basin is located on the southeastern Tibetan Plateau,China,and contains massive evaporites.The origin of evaporites in the basin has been hotly debated because of the strong transformation by tectonic movement.Forty halite samples from borehole MK-3 in the Mengyejing area of the basin were collected and analyzed using XRD,Cl-Sr isotopes and chemical compositions to trace the origin of the evaporites in the basin.The Br×10^(3)/Cl ratios of the halite samples are between 0 and 0.55,most of which are synchronized with the law of seawater evaporation and at the stage of halite precipitation from seawater,indicating that the evaporites are mainly of marine origin.The^(87)Sr/^(86)Sr ratios range from 0.707489 to 0.711279;after correction,the^(87)Sr/^(86)Sr 145 Ma ratios range from 0.704721 to 0.707611,equivalent with the 87Sr/86Sr ratios of seawater at 145 Ma,indicating a marine origin.The decay of 87Rb in the evaporite during deposition,change of the depositional environment and the unsealed environment at a later period resulted in the present^(87)Sr/^(86)Sr ratios of some samples being high.The δ^(37)Cl value compositions range from−0.38‰to 0.83‰,which is consistent with the δ^(37)Cl value composition of the world marine halite(−0.6‰to 0.4‰),further confirming that seawater is the main origin.In addition,the high δ^(37)Cl value of some samples at the boundary of the upper and lower evaporite layers might be related to the influence of δ^(37)Cl-rich brine and the incomplete dissolution of the halite.

关键词： evaporites halite potash Cl-Sr isotopes Lanping-Simao Basin

重组牛碱性成纤维细胞生长因子辅助治疗凹陷性痤疮瘢痕的临床观察

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中国医学科学院学报 2022年第2期44卷 208-212页

作者：杜红霞胡媛媛信阳市中心医院皮肤科河南信阳464000 信阳市中心医院医疗美容科河南信阳464000

目的探讨重组牛碱性成纤维细胞生长因子辅助治疗对凹陷性痤疮瘢痕患者瘢痕改善情况及炎性因子的影响。方法采用随机数字表法将120例凹陷性痤疮瘢痕患者分为试验组和对照组。两组患者均接受CO_(2)点阵激光治疗,术后对照组常规涂抹红霉素... 详细信息

目的探讨重组牛碱性成纤维细胞生长因子辅助治疗对凹陷性痤疮瘢痕患者瘢痕改善情况及炎性因子的影响。方法采用随机数字表法将120例凹陷性痤疮瘢痕患者分为试验组和对照组。两组患者均接受CO_(2)点阵激光治疗,术后对照组常规涂抹红霉素眼膏,试验组术后涂抹重组牛碱性成纤维细胞生长因子凝胶。分析随访治疗1个月后的临床疗效、临床相关指标、治疗前后瘢痕改善情况、炎性因子水平及不良反应情况。结果治疗后试验组总有效率高于对照组(P=0.040),总不良反应发生率低于对照组(P=0.028)。与对照组比较,试验组患者红斑持续时间明显缩短(P=0.025),结痂时间(P=0.002)及水肿消退时间(P<0.001)均明显提前。与治疗前比较,治疗后试验组和对照组患者Goodman和Baron痤疮瘢痕分级1级比例明显升高(P=0.001,P=0.027),4级比例明显下降(P<0.001,P=0.034),且治疗后试验组1级比例高于对照组(P=0.031),4级比例低于对照组(P=0.031)。与治疗前比较,治疗后两组患者血清肿瘤坏死因子-α、白细胞介素-1β水平均降低(P均<0.001),且试验组低于对照组(P均<0.001)。结论在CO_(2)点阵激光治疗基础上辅以重组牛碱性成纤维细胞生长因子凝胶治疗,可更有效地改善凹陷性痤疮瘢痕患者面部瘢痕情况,缓解局部炎症反应,疗效好,不良反应少。

关键词：凹陷性痤疮瘢痕重组牛碱性成纤维细胞生长因子炎性因子不良反应

Photochemical production of carbonyl sulfide,carbon disulfide and dimethyl sulfide in a lake water

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Journal of Environmental Sciences 2017年第1期29卷 146-156页

作者： Qianqian du Yujing Mu Chenglong Zhang Junfeng Liu yuanyuan Zhang Chengtang Liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Photochemical production of carbonyl sulfide（COS）,carbon disulfide（CS_2） and dimethyl sulfide（DMS） was intensively studied in the water from the Aohai Lake of Beijing city.The lake water was found to be highly supersaturated with COS,CS_2 and DMS,with their initial concentrations of 0.91 ± 0.073 nmol/L,0.55 ± 0.071 nmol/L and 0.37 ± 0.062 nmol/L,respectively.The evident photochemical production of COS and CS_2 in the lake water under irradiation of 365 nm and 302 nm indicated that photochemical production of them might be the reason for their supersaturation.The similar dependence of wavelength and oxygen for photochemical production of COS,CS_2 and DMS implied that they might be from the same precursors.The water cage effect was found to favor COS production but inhibit CS_2and DMS formation,indicating that COS photochemical production was mainly from direct degradation of the precursors and the formation of CS_2 and DMS needed intermediates via combination of carbon-centered radicals and sulfur-centered radicals.The above assumptions were further confirmed by simulation experiments with addition of carbonyls and amino acids（cysteine and methionine）,and the photochemical formation mechanisms for COS,CS_2 and DMS in water were derived from the investigations.

关键词： Photochemical production Carbonyl sulfide Carbon disulfide Dimethyl sulfide Water

Application of Zero-Watermarking for Medical Image in Intelligent Sensor Network Security

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Computer Modeling in Engineering & Sciences 2023年第7期136卷 293-321页

作者： Shixin Tu yuanyuan Jia Jinglong du Baoru Han Medical Data Science Academy College of Medical InformaticsChongqing Medical UniversityChongqing400016China

The field of healthcare is considered to be the most promising application of intelligent sensor networks.However,the security and privacy protection ofmedical images collected by intelligent sensor networks is a hot problem that has attracted more and more attention.Fortunately,digital watermarking provides an effective method to solve this problem.In order to improve the robustness of the medical image watermarking scheme,in this paper,we propose a novel zero-watermarking algorithm with the integer wavelet transform(IWT),Schur decomposition and image block energy.Specifically,we first use IWT to extract low-frequency information and divide them into non-overlapping blocks,then we decompose the sub-blocks by Schur decomposition.After that,the feature matrix is constructed according to the relationship between the image block energy and the whole image energy.At the same time,we encrypt watermarking with the logistic chaotic position scrambling.Finally,the zero-watermarking is obtained by XOR operation with the encrypted watermarking.Three indexes of peak signal-to-noise ratio,normalization coefficient(NC)and the bit error rate(BER)are used to evaluate the robustness of the algorithm.According to the experimental results,most of the NC values are around 0.9 under various attacks,while the BER values are very close to 0.These experimental results show that the proposed algorithm is more robust than the existing zero-watermarking methods,which indicates it is more suitable for medical image privacy and security protection.

关键词： Intelligent sensor network medical image zero-watermarking integer wavelet transform schur decomposition