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铸件X射线检测虚拟探伤图像生成方法

铸造 2024年第6期73卷 835-842页

作者：董淏侯明君计效园李沁阳吴楚澔李硕宏郄喜望陈强李宁周建新高亮华中科技大学材料成形与模具技术全国重点实验室湖北武汉430074 中国航发北京航空材料研究院北京100095 中国兵器工业第五九研究所重庆710100 华中科技大学机械科学与工程学院湖北武汉430074

随着国防核心装备对零件的要求不断提高,铸件向结构复杂化方向发展,如大壁厚差、多交叉结构等,致使铸件内部缺陷的无损检测更困难。X射线探伤过程中,拍片依赖人工反复调整成像部位和参数,存在探伤部位易漏检、成像质量波动大等问题,亟... 详细信息

随着国防核心装备对零件的要求不断提高,铸件向结构复杂化方向发展,如大壁厚差、多交叉结构等,致使铸件内部缺陷的无损检测更困难。X射线探伤过程中,拍片依赖人工反复调整成像部位和参数,存在探伤部位易漏检、成像质量波动大等问题,亟需发展智能分区调参拍片技术。为此,本文提出了铸件X射线检测虚拟探伤图像生成方法。首先,建立了铸件坐标降维映射模型,实现了铸件三维坐标降维映射到成像板平面二维坐标。其次,建立了仿真成像参数拟合模型,生成了点光源式虚拟射线对铸件三维模型的仿真探伤图像。最后,开发了铸件X射线检测虚拟成像系统。该方法可为实际探伤提供优化的成像姿态和成像参数信息,为智能分区调参拍片技术提供理论支撑。

关键词： X射线探伤铸件三维模型点光源成像虚拟探伤图像

Assessment of visual outcomes of cataract surgery in Tujia nationality in Xianfeng County, China

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 292-298页

作者： Jing Yuan Xia Wang li-qin yang Yi-Qiao Xing Yan-Ning yang Eye Center Renmin Hospital of Wuhan University Department of Ophthalmology Xianfeng County Renmin Hospital

AIM: To evaluate the visual outcome and factors influencing visual outcome of manual small incision cataract surgery(MSICS) in the rural area in the Xianfeng ***: Eighty-two eyes of 82 patients who underwent cataract surgery performed by using MSICS technique were identified. Data collected included each patient’s age, gender, the level of education. Uncorrected and corrected distance visual acuity(UDVA and CDVA) at presentation and at 1, 6, 8wk postoperatively, pre-existing eye disease, operative findings and complications, the risk factors were ***: In 82 patients, the average age was 69.6±0.6y, illiterate were 52(63.4%). Of 82 eyes, pseudophakia was present in 77 eyes(93.9%). At 1wk postoperatively,47 eyes(57.3%) had the UDVA of ≥6/18, and 52 eyes(63.4%) had the CDVA of ≥6/18. At 6 to 8wk postoperatively, 50 eyes(61.0%) had UDVA of ≥6/18, and57 eyes(69.5%) had the CDVA of ≥6/18. Postoperative visual status was significantly related to the co-morbidities, such as corneal pathology, glaucoma(P lications, such as posterior capsule opacity and cystoid macular edema were main operative cause for the poor visual ***: MSICS provides a good visual recovery in our study but the vision outcome did not fulfill the standards proposed by WHO, which highlights the need for an improvement in local socioeconomic understanding, population education and surgery quality.

关键词： cataract surgery manual small incision cataract surgery visual outcome co-morbidities operative complications

Microstructure and tensile properties of Mo alloy synthetically strengthened by nano-Y_2O_3 and nano-CeO_2

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Rare Metals 2014年第1期33卷 58-64页

作者： Ren-Zhi liu Kuai-She Wang Peng-Fa Feng Geng An qin-li yang Hu Zhao Institute of Metallurgy Xi’an University of Architecture and Technology Laboratory of Molybdenum Metal and Its Processing Jinduicheng Moly Co. Ltd State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University

Nano-Y2O3 and nano-CeO2 of different weight ratio mixed with deionizing water were doped into MoO2 powder by liquid-solid doping method. The diameter 1.80 and 0.18 mm alloy wires of Mo-0.3Y, Mo-0.3Ce, and Mo-0.15Y-0.15Ce were prepared through reduction, iso- static pressing, sintering, and drawing. Tensile properties, second phase microstructure and fracture surface appear- ance of wires were analyzed. The better refining effect for Mo alloy powder can be gotten after two kinds of nano- particle oxide doped into MoO2 than only one doped. Nano-Y2O3 and nano-CeO2 have different influences on sintering process. For nano-CeO2, the constraining effect of grain growth focuses on the initial sintering stage, nano- Y2O3 plays refining grains roles in the later densification stage. Nano-Y2O3 is undistorted and keeps intact in the process of drawing; and nano-CeO2 is elongated and bro- ken into parts in the drawing direction. The strengthening effect of nano-Y2O3 and nano-CeO2 keeps the finer grains and superior tensile properties for Mo-0.15Y-0.15Ce wire.

关键词： Nano-Y2O3 Nano-CeO2 Mo alloy wire Microstructure Tensile property Fracture surface

Reaction mechanism of lanthanum nitrate-doped Mo–La material during solid–liquid spray doping processing

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Rare Metals 2015年第11期34卷 814-817页

作者： Peng-Fa Feng qin-li yang Xiao-Ming Dang Sha Xi Ya-Qi Wang Jinduicheng Molybdenum Co. Ltd

At three critical temperatures which were obtained by thermo-gravimetry-differential thermal analysis–differential scanning calorimetry（TG/DTG/DSC）curves of lanthanum nitrate crystal, the air thermal decomposition experiments and solid–liquid spray doping simulation procedures of lanthanum nitrate crystal were carried out, and their products were analyzed by X-ray diffraction（XRD）. Meanwhile, the spray doping processing of Mo O2–50 wt% La（NO3）3composite powder was undergone with lanthanum nitrate solution as the dopant,and doped Mo O2powder was analyzed by XRD. The results demonstrate that during the traditional solid–liquid spray doping processing, lanthanum nitrate, in the form of either crystal or aqueous solution, would be converted into La（NO3）3á4H2O by the dehydration reaction, rather than be decomposed to La2O3and NO or NO2. Therefore, it is inferred that the oxynitride gas produced from the process is attributed to the decomposition of residual HNO3in lanthanum nitrate crystal. The source of HNO3is supported by the chemical composition of lanthanum nitrate crystal.

关键词： Solid–liquid spray doping processing Mo O2 Lanthan

Neolithic millet farmers contributed to the permanent settlement of the Tibetan Plateau by adopting barley agriculture

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National Science Review 2019年第5期6卷 1005-1013页

作者： Yu-Chun li Jiao-yang Tian Feng-Wen liu Bin-Yu yang Kang-Shu-Yun Gu Zia Ur Rahman li-qin yang Fa-Hu Chen Guang-Hui Dong qing-Peng Kong State Key Laboratory of Genetic Resources and Evolution/Key Laboratory of Healthy Aging Research of Yunnan Province Kunming Institute of Zoology Chinese Academy of Sciences CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences Key Laboratory of Western China’s Environmental Systems(Ministry of Education) Lanzhou University CAS Center for Excellence in Tibetan Plateau Earth Sciences and Key Laboratory of Alpine Ecology Institute of Tibetan Plateau Research(ITPCAS) Chinese Academy of Sciences

The permanent human settlement of the Tibetan Plateau(TP) has been suggested to have been facilitated by the introduction of barley agriculture ～3.6 kilo-years ago(ka).However, how barley agriculture spread onto the TP remains *** that the lower altitudes in the northeastern TP were occupied by millet cultivators from 5.2 ka, who also adopted barley farming ～4 ka, it is highly possible that it was millet farmers who brought barley agriculture onto the TP ～3.6 *** test this hypothesis, we analyzed mitochondrial DNA(mt DNA) from 8277 Tibetans and 58 514 individuals from surrounding populations,including 682 newly sequenced whole *** lines of evidence, together with radiocarbon dating of cereal remains at different elevations, supports the scenario that two haplogroups(M9a1a1c1b1a and A11a1a), which are common in contemporary Tibetans(20.9%) and were probably even more common(40–50%) in early Tibetans prior to historical immigrations to the TP, represent the genetic legacy of the Neolithic millet *** haplogroups originated in northern China between 10.0–6.0 ka and differentiated in the ancestors of modern Tibetans ～5.2–4.0 ka, matching the dispersal history of millet *** showing that substantial genetic components in contemporary Tibetans can trace their ancestry back to the Neolithic millet farmers, our study reveals that millet farmers adopted and brought barley agriculture to the TP ～3.6–3.3 ka, and made an important contribution to the Tibetan gene pool.

关键词： Tibetans millet farmers barley agriculture archaeology mitochondrial genomes

Enhancing the mechanical properties of casting eutectic high -entropy alloys via W addition

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1364-1372页

作者： Xu yang Dezhi Chen li Feng Gang qin Shiping Wu Ruirun Chen National Key Laboratory for Precision Hot Processing of Metals School of Material Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy alloys(HEAs)were *** show that the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs are composed of face-centered cubic and body-centered cubic(BCC)*** W content increases,the microstructure changes from eutectic to *** addition of W lowers the nucleation barrier of the BCC phase,decreases the valence electron concentration of the HEAs,and replaces Al in the BCC phase,thus facilitating the nucleation of the BCC *** results show that the addition of W greatly improves the mechanical properties,and solid-solution,heterogeneous-interface,and second-phase strengthening are the main strengthening *** yield strength,tensile strength,and elongation of the Al_(1.25)CoCrFeNi2.95W0.05 HEA are 601.44 MPa,1132.26 MPa,and 15.94%,respectively,realizing a balance between strength and *** fracture mode of the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs is ductile–brittle mixed fracture,and the crack propagates and initiates in the BCC *** eutectic lamellar structure impedes crack propagation and maintains plasticity.

关键词： high-entropy alloy microstructure mechanical property fracture behavior

Weather and Birth Weight:Different Roles of Maternal and Neonatal GPR61 Promoter Methylation

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Biomedical and Environmental Sciences 2022年第3期35卷 181-193页

作者： li Zhi Yuan GONG Yong Xiang yang Meng CHAI Jian SUN Ren Jie li qin yang HE Ya Nan HUANG Hui ZHANG Ya Wei BA Yue ZHOU Guo Yu Department of Environmental Health&Environment and Health Innovation Team School of Public HealthZhengzhou UniversityZhengzhou 450001HenanChina National Health Commission Key Laboratory of Birth Defects Prevention Henan Key Laboratory of Population Defects PreventionHenan Institute of Reproduction Health Science and TechnologyZhengzhou 450002HenanChina Yellow River Institute for Ecological Protection&Regional Coordinated Development Zhengzhou UniversityZhengzhou 450001HenanChina Department of Environment Health Science Yale University School of Public HealthNew HavenCTUSA

Objectives It is unclear whether G protein-coupled receptor 61(GPR61)affecting body weight,plays a role in the association between birth weight and *** study aimed to assess the effects of prenatal weather and GPR61 on birth *** A total of 567 mother-newborn pairs were recruited in Houzhai Center Hospital during2011–*** detected the maternal and neonatal GPR61 promoter methylation levels,and obtained meteorological and air pollution *** A positive association was observed between maternal and neonatal GPR61 methylation levels,and both of them were affected by precipitation,relative humidity(RH)and daily temperature range(DTR).Birth weight was associated negatively with RH and positively with DTR(Plity of birth weight to prenatal weather conditions,while neonatal GPR61 methylation may be a bridge of the effects of prenatal RH and DTR on birth weight.

关键词： Pregnancy Weather Birth weight GPR61 gene DNA methylation Mother-newborns

Maximum initial primary wave model for low-Froude-number reservoir landslides based on wave theory

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Journal of Mountain Science 2024年第8期21卷 2664-2680页

作者： li yang HUANG Bolin qin Zhen DONG Xingchen HU Lei National Field Observation and Research Station of Landslides in Three Gorges Reservoir Area of yangtze River Yichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China

The impulse waves induced by large-reservoir landslides can be characterized by a low Froude ***,systematic research on predictive models specifically targeting the initial primary wave is *** the Shuipingzi 1#landslide that occurred in the Baihetan Reservoir area of the Jinsha River in China as an engineering example,this study established a large-scale physical model(with dimensions of 30 m×29 m×3.5 m at a scale of 1:150)and conducted scaled experiments on 3D landslide-induced impulse *** the process in which a sliding mass displaced and compressed a body of water to generate waves,the maximum initial wave amplitude was found to be positively correlated with the sliding velocity and the volume of the *** the increase in the water depth,the wave amplitude initially increased and then *** duration of pressure exertion by the sliding mass at its maximum velocity directly correlated with an elevated wave *** on the theories of low-amplitude waves and energy conservation,while considering the energy conversion efficiency,a predictive model for the initial wave amplitude was *** model could fit and validate the functions of wavelength and wave *** accuracy of the initial wave amplitude was verified using physical experiment data,with a prediction accuracy for the maximum initial wave amplitude reaching 90%.The conversion efficiency(η)directly determined the accuracy of the estimation *** clear conditions for landslide-induced impulse wave generation,estimating the value ofηthrough analogy cases was *** study has derived the landslide-induced impulse waves amplitude prediction formula from the standpoints of wave theory and energy conservation,with greater consideration given to the intrinsic characteristics in the formation process of landslide-induced impulse waves,thereby enhancing the applicability and extensibility of the *** can facilitate the development

关键词： Three-dimensional physical model experiments Reservoir-landslide-induced impulse wave Energy conversion efficiency Landslide-induced impulse wave prediction model Shuipingzi 1#landslide

Asymmetric synthesis of L-carnitine from (R)-3-chloro-1,2-propanediol

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Chinese Chemical Letters 2011年第7期22卷 765-767页

作者： Xu qin li Yun Xu yang Wei li Wang Bin Hu Hui Min Xue Tian Yi Zhang Xue Tao Zhang Department of Chemistry University of Science and Technology Beijing Beijing 100083 China

A practical chemical synthesis of L-camitine （1） has been accomplished from （R）-3-chloro-1,2-propanediol （（R）-4）, which is a main by-product originated from （R,R）-Salen Co（III） catalyzed hydrolytic kinetic resolution （HKR） of （±）-epichlorohydrin. （R）-4 was utilized as a chiral starting material to prepare the key intermediate cyclic sulfite （（R）-S）. The new synthetic approach demonstrated an efficient utilization of organic by-product for the asymmetric synthesis of bioactive compounds.

关键词： L-Camitine Cyclic sulfite (R)-3-Chloro-1,2-propanediol