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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 620-629页

作者： Xiao-jie Zhao zhi-nan yang fu-cheng Zhang State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004China

The bainitic transformation of the steels with different mass fractions of N, ~0.002% and 0.021%, was observed in situ by using high-temperature metalloscope. Micrometer-and nanometer-sized aluminum nitride(AlN) particles were found in the steel with 0.021% *** boundaries, the interior of the grains, and Al N particles were used as initial nucleation sites of bainitic ferrite, and bainitic ferrite subunits served as new nucleation sites to induce secondary nucleation. The lengthening rate of bainitic ferrite varied at different nucleation sites, which was controlled by the repeated nucleation and growth of bainitic subunits. The Al N particles not only provided several nucleation sites, but also increased the autocatalytic effect on the transformation, further shortening the incubation period, promoting the bainitic transformation, and refining the bainitic microstructure.

关键词： bainitic steel In situ observation phase transformation aluminum nitride

Solute Clusters/Enrichment at the Early Stage of Ageing in Mg-Zn-Gd Alloys Studied by Atom Probe Tomography

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Acta Metallurgica Sinica(English letters) 2019年第2期32卷 187-193页

作者： Xin-fu gu Tadashi furuhara leng Chen Ping yang School of Materials Science and Engineering University of Science and Technology Beijing Institute for Materials Research Tohoku University

Three-dimensional distribution of solute elements in an Mg–Zn–Gd alloy during ageing process is quantitatively characterized by three-dimensional atom probe(3DAP) tomography. Based on the radius distribution function, it is found that Zn–Gd solute pairs in Mg matrix appear mainly at two peaks at early stage of ageing, and the separation distance between Zn and Gd atoms could be well rationalized by the first-principle calculation. Moreover, the fraction of Zn–Gd solute pairs increases first and then decreases due to the precipitation of long-period stacking ordered(LPSO) structures. Both the composition of the structural unit in LPSO structure and the solute enrichment around it are quantified. It is found that Zn and Gd elements are synchronized in the LPSO structure, and solute segregation of pure Zn or Gd is not observed at the transformation front of the LPSO structure in this alloy. In addition, the crystallography of transformation front is further determined by 3DAP data.

关键词： Magnesium alloy Long-period stacking ordered(LPSO) Atomic cluster Three-dimensional atom probe(3DAP) Crystallography

Must Peutz-Jeghers syndrome patients have the LKB1/STK11 gene mutation?A case report and review of the literature

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World Journal of Clinical Cases 2018年第8期6卷 224-232页

作者： fu-Xiao Duan guo-Li gu Hai-Rui yang Peng-Fei Yu zhi Zhang Department of General Surgery Air Force General Hospital of Chinese PLA

Peutz-Jeghers syndrome(PJS) is an autosomal dominant inherited disease, which is characterized by mucocutaneous pigmentation and multiple gastrointestinal hamartoma polyps. The germline mutation of LKB1/STK11 gene on chromosome 19 p13.3 is considered to be the hereditary cause of PJS. However, must a patient with PJS have the LKB1/STK11 gene mutation? We here report a case of a male patient who had typical manifestations of PJS and a definite family history, but did not have LKB1/STK11 gene mutation. By means of high-throughput sequencing technology, only mutations in APC gene(c.6662 T > C: ***2221 Thr) and MSH6 gene(c.3488 A > T: ***1163 Val) were detected. The missense mutations in APC and MSH6 gene may lead to abnormalities in structure and function of their expression products, and may result in the occurrence of PJS. This study suggests that some other genetic disorders may cause PJS besides LKB1/STK11 gene mutation.

关键词： Peutz-Jeghers syndrome Gastrointestinal polyps High-throughput sequencing LKB1/STK11 APC MSH6 Hamartoma

Growth and yield responses to simulated hail damage in drip-irrigated cotton

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Journal of Integrative Agriculture 2022年第8期21卷 2241-2252页

作者： WANG le LIU yang WEN Ming LI Ming-hua DONG zhi-qiang CUI Jing MA fu-yu Agricultural College Shihezi University/National and Local Joint Engineering Research Center of Information Management and Application Technology for Modern Agricultural Production(XPCC)Shihezi 832003P.R.China

The frequent occurrence of hailstorm in Xinjiang affects cotton(Gossypium hirsutum L.)production and causes enormous economic *** indeterminate growth habit of cotton allows for varying degrees of recovery and yield when different hail damage levels occur at different stages,which brings inconvenience to agricultural insurance claims and post-damage ***,this study aimed to elucidate cotton recovery and yield responses to different levels of simulated hail damage at different growth *** levels of hail damage(0,30,60,and 90%)were simulated every 15 d from the five-leaf stage to the boll opening stage in 2018 and 2019,for a total of six times(Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,and Ⅵ).The results showed that seed cotton yield decreased as the damage level increased and yield reduction increased when the damage was applied to older plants(for 30,60 and 90% damage levels,yield reduction was 9-17%,22-37% and 48-71%,respectively).One possible reason was that the leaf area index and leaf area duration of plant canopy decreased after hail damage,resulting in a reduction in the accumulation of above-ground ***,when hail damage occurred before bloom,due to the indeterminate growth habit of cotton,the vegetative organs produced a strong compensation ability that promoted the bud *** compensation ability of vegetative organs decreased when hail damage occurred after bloom and the recovery time was too short to promote new boll *** the first study to understand the recovery of cotton after hail damage,it analyzed the leaf area index,leaf area duration,above-ground biomass accumulation and yield,rather than the yield *** findings are of great importance for cotton production as they inform decisions about post-damage management practices,yield forecasts and insurance compensation.

关键词： cotton compensation growth simulated hail damage yield

Optimal Micro-PMU Placement for Improving State Estimation Accuracy via Mixed-integer Semidefinite Programming

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Journal of Modern Power Systems and Clean Energy 2023年第2期11卷 468-478页

作者： yang Peng zhi Wu Wei gu Suyang Zhou Pengxiang Liu School of Electrical Engineering Southeast UniversityNanjingChina

Micro-phasor measurement units(μPMUs)with a micro-second resolution and milli-degree accuracy capability are expected to play an important role in improving the state estimation accuracy in the distribution network with increasing penetration of distributed ***,this paper investigates the problem of how to place a limited number ofμPMUs to improve the state estimation *** with pseudo-measurements and supervisory control and data acquisition(SCADA)measurements,an optimalμPMU placement model is proposed based on a two-step state estimation *** E-optimal experimental criterion is utilized to measure the state estimation *** nonlinear optimization problem is transformed into a mixed-integer semidefinite programming(MISDP)problem,whose optimal solution can be obtained by using the improved Benders decomposition *** on several systems are carried out to evaluate the effective performance of the proposed model.

关键词： Phasor measurement unit(PMU) distribution system state estimation mixed-integer semidefinite programming(MISDP)

Phase selection and solidification path transition of Ti-48Al-xNb alloys with different cooling rates

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Rare Metals 2023年第1期42卷 288-295页

作者： Tan He Rui Hu Jie-Ren yang Heng-zhi fu The State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an710072China

Ti-48Al-xNb alloys were solidified by containerless electromagnetic levitation with quenching system of the conical copper *** influence of cooling rates on phase selection of T1-48Al-xNb alloys was *** near-equilibrium solidification condition,the dendrite βphase is observed as the leading *** other metastable phase(e.g.,α phase) is *** contrast,in rapid solidification condition,the metastable α phase is observed in as-quenched Ti-48Al-2Nb ***,the metastable α phase is replaced by the primary β phase with Nb addition *** Ti-48Al-(x=4,6,8)Nb alloys,increasing cooling rate results in a solidification path *** peritectic reaction(L+β→α) is therefore significantly *** relationships between primary dendrite arm spacing(λ_(1)) and cooling rate(τ) can be described.

关键词： TiAl alloy Cooling rate Microstructure Phase selection

Association between Adiponectin and Metabolic Syndrome in Older Adults from Major Cities of China

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Biomedical and Environmental Sciences 2010年第1期23卷 53-61页

作者： QIN ZHUO zhi-QING WANG PING fu JIAN-HUA PIAO YUAN tian JIE XU XIAO-guANG yang National Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100050 China Centre for Chrom'c Diseases School of Medicine University of Queensland Brisbane QLD 4072 Australia

Objective To investigate the association between adiponectin and metabolic syndrome （MetS） and related diseases in older adults from major cities of China. Methods A total of 2 049 adults at the age of 60-96 years from18 major cities of China were enrolled in the study. Plasma adiponectin and insulin concentrations were measured. Insulin resistance was assessed by homeostasis model assessment of insulin resistance （HOMA-IR）. The definitions proposed by International Diabetes Federation （IDF） and American Heart Association/National Heart, Lung, and Blood/nstitute （AHA/NLHBI） were used to identify MetS. Results The adiponectin concentration increased with the advance of age and was higher in women than in men. The sex specific adiponectin concentration was inversely correlated with body mass index （BMI）, waist circumference, diastolic blood pressure, triglycerides, glucose and fasting blood insulin, and positively correlated with HDL-C （P〈0.001）. The adiponectin concentration decreased with increasing MetS components. Compared with the 4th sex-specific adiponectin quartile, the odds ratio （OR） for prevalent MetS-IDF and MetS-AHA/NLHBI in subjects of the 1st quartile group was 3.25 （95% CI： 2.24, 4.71） and 3.21 （95% CI： 2.26, 4.55）, respectively. The association was independent of age, sex, life-style factors, medication, family history of chronic diseases, BMI, and HOMA-IR, The OR for MetS was much higher than those of MetS components and its related diseases. Conclusion Adiponectin is strongly associated with MetS independent of insulin resistance and obesity in older adults from major cities in China. The adiponectin concentration is a useful predictor for the risk of MetS.

关键词： Adiponectin Metabolic syndrome Chinese older adults Obesity Insulin resistance

Surface effect induced phase transformation by Mn removal during annealing and its textures in cold-rolled high manganese transformation-induced plasticity steel

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Journal of Iron and Steel Research International 2022年第3期29卷 494-502页

作者： Li-ying Liu Ping yang Dan-dan Ma Xin-fu gu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China

The surface effect induced transformation texture during vacuum annealing of cold-rolled high manganese transformation-induced plasticity(TRIP)steels was *** to Mn removal occurring at the surface layer,γ→δdiffusional phase transformation leads to the formation of hard pancake-shaped ferrite grains due to solution strengthening at the surface and the centre layer remains as austenite+martensite after *** the case of slow heating,{112}/{111}textures for the surface ferrite were strengthened with the increase in temperature and holding time,indicating an inheritance of rolling *** increasing the heating rate of annealing,the rotated cube texture was developed in surface *** kind of multiphase sandwich structure with hard ferrite surface layer and tough austenite dominant centre can increase tensile strength and should also improve deep drawing properties,therefore providing new possibility of controlling properties for the application of high manganese TRIP steel.

关键词： High manganese transformation-induced plasticity steel Surface effect Texture Microstructure Vacuum annealing

Mechanism of signal uncertainty generation for laser-induced breakdown spectroscopy

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Frontiers of physics 2021年第2期16卷 35-44页

作者： yang-Ting fu Wei-Lun gu Zong-Yu Hou Sher Afgan Muhammed tian-Qi Li Yun Wang Zhe Wang State Key Lab of Power Systems International Joint Laboratory on Low Carbon Clean EnergyInnovationDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Renewable Energy Resources Laboratory(RERL)&National fuel Cell Research Center Department of Mechanical and Aerospace EngineeringThe University of CaliforniaIrvineCA 92697-3975USA

Relatively large measurement uncertainty severely hindered wide application for laser-induced breakdown spectroscopy(LIBS),therefore it is of great importance to understand the mechanism of signal uncertainty generation,including initiation and *** has been found that the Auctuation of plasma morphology was the main reason for signal ***,it still remains unclear what mechanism leads to laser-induced plasma morphology *** the present work,we employed three fast-imaging cameras to capture three successive plasma images fromn a same laser-induced Titanium alloy plasma,which enables us to understand more clearly of the plasma evolution process especially for the early plasma evolution stage when plasma and surrounding gases interact *** from the images,the plasma experienced an increasing morphological fuctuation as delay time increased,transforming from a“stable plasma”before the delay time of 100 ns to a“fuctuating plasma”after the delay time of 300 ***,the frontier part of plasma showed a significant down-ward motion from the delay time of 150 ns to 200 ns and crashed with the lower part of the plasma,making the plasma fatter and later even splitting the plasma into two parts,which was considered as a critical process for the transformation of“stable plasma”to“unstable plasma”.By calculating the correlation coefficient of plasma image pairs at successive delay times,it was found that the higher the similarity between two plasma at early stage,the more similar at later stage;this implied that the tiny plasma fuctuation earlier than the critical delay time(150-200 ns)was amplifed,causing a large plasma fluctuation at the later stage as well as LIBS measurement *** initation of slight fluctuation was linked with Rayleigh-Taylor Instability(RTI)due to the drastic material interpenetration at the plasma-ambient gas interface at earlier stage(before 50 ns).That is,the uncertainty generation of LIBS was p

关键词： LIBS laser-induced breakdown spectroscopy signal uncertainty Rayleigh-Taylor instability

The Possible Effect of Climate Warming on Northern Limits of Cropping System and Crop Yield in China

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Agricultural Sciences in China 2011年第4期10卷 585-594页

作者： yang Xiao-guang LIU zhi-juan CHEN fu College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R. China College of Agronomy and Biotechnology China Agricultural University Beijing 100193 P.R.China

Significantly increasing temperature since the 1980s in China has become a consensus under the background of global climate change and how climate change affects agriculture or even cropping systems has attracted more and more attention from Chinese government and scientists. In this study, the possible effects of climate warming on the national northern limits of cropping systems, the northern limits of winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation in China from 1981 to 2007 were analyzed. Also, the possible change of crop yield caused by planting limits displacement during the periods 1950s-1981 and 1981-2007 was compared and discussed. The recognized calculation methods of agricultural climatic indices were employed. According to the indices of climatic regionalization for cropping systems, the national northern limits of cropping systems, winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation during two periods, including the 1950s-1980 and 1981-2007, were drawn with ArcGIS software. Compared with the situation during the 1950s- 1980, the northern limits of double cropping system during 1981-2007 showed significant spatial displacement in Shaanxi, Shanxi, Hebei, and Liaoning provinces and Beijing municipality, China. The northern limits of triple cropping system showed the maximum spatial displacement in Hunan, Hubei, Anhui, Jiangsu, and Zhejiang provinces, China. Without considering variety change and social economic factors, the per unit area grain yield of main planting patterns would increase about 54-106% if single cropping system was replaced by double cropping system, which turned out to be 27- 58% if double cropping system was replaced by triple cropping system. In Liaoning, Hebei, Shanxi, Shaanxi, Gansu, and Qinghai provinces, Inner Mongolia and Ningxia autonomous regions, China, the northern limits of winter wheat during 1981-200

关键词： climate warming the northern limits of cropping system the planting northern limits of winter wheat the planting northern limits of double rice crop yield