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酒精性肝损伤与肝炎性肝损伤CT诊断及鉴别诊断

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中外医药研究 2024年第17期3卷 126-128页

作者：万能凯里市第一人民医院贵州凯里556000

目的:探析酒精性肝损伤、肝炎性肝损伤应用CT诊断的临床鉴别诊断价值。方法:选取2019年7月—2024年2月于凯里市第一人民医院就诊并拟诊断为酒精性肝损伤与肝炎性肝损伤患者共72例作为研究对象,依据疾病类型分为参照组(酒精性肝损伤)与... 详细信息

目的:探析酒精性肝损伤、肝炎性肝损伤应用CT诊断的临床鉴别诊断价值。方法:选取2019年7月—2024年2月于凯里市第一人民医院就诊并拟诊断为酒精性肝损伤与肝炎性肝损伤患者共72例作为研究对象,依据疾病类型分为参照组(酒精性肝损伤)与试验组(肝炎性肝损伤),各36例。两组均进行CT筛查诊断。比较两组临床CT鉴别诊断准确率、肝脾比值、肝密度CT值、肝体积增大与肝形态正常发生率。结果:两组CT诊断准确率比较,差异无统计学意义(P>0.05);试验组肝脾比值低于参照组,肝密度CT值高于参照组,差异有统计学意义(P<0.05);参照组肝体积增大与肝形态正常发生率高于试验组,差异有统计学意义(P<0.05)。结论:CT诊断在酒精性肝损伤、肝炎性肝损伤中有很大的应用价值,CT差异性可有效鉴别诊断两组症状形式,但酒精性肝损伤的CT值相对偏低,且肝体积增大及肝形态正常发生率较高。

关键词：酒精性肝损伤肝炎性肝损伤 CT诊断鉴别诊断

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基于误差分布图的五轴在机测量路径优化方法

航空学报 2024年第13期45卷 229-241页

作者：郭彦亨万能庄其鑫刘博李欣欣王道西北工业大学机电学院西安710072 中国航发南方工业有限公司株洲412002

五轴在机测量中,测量路径规划同时决定标定效率、测量效率和机床定位误差影响下的测量精度。为了获得兼顾测量精度与效率的最优测量工艺,提出了一种基于误差分布图的在机测量路径优化方法。首先,根据干涉检查结果构建各待测点的测量可... 详细信息

五轴在机测量中,测量路径规划同时决定标定效率、测量效率和机床定位误差影响下的测量精度。为了获得兼顾测量精度与效率的最优测量工艺,提出了一种基于误差分布图的在机测量路径优化方法。首先,根据干涉检查结果构建各待测点的测量可行图。接着,利用定位误差影响模型预测可行图内的测量误差分布。为满足在机测量精度和效率最优,以测量误差作为精度优化目标,结合测量路径长度和标定点数量构建效率优化目标,建立多目标优化模型。基于NSGA-Ⅱ求解模型,优化测量路径。最后,以离心式叶轮为例进行验证,采用此方法不仅能减少红宝石触碰点和测量路径长度以提高效率,同时还能精确补偿预行程误差并减少引入的机床定位误差影响以提升测量精度,实验结果表明该优化方法使标定时间减少55.28%,测量时间减少10.2%,同时平均测量误差减少26.7%,说明该方法具有良好的可行性。

关键词：在机测量测量可行图测量误差预行程误差路径规划

大跨度斜拉桥钢-混组合梁一维日照温度场高效数值模型构建及试验验证

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工程力学 2024年第S01期41卷 197-205页

作者：黄民水张健蔚罗金万能邓志航何仲骜武汉工程大学土木工程与建筑学院武汉430074 绿色土木工程材料与结构湖北省工程研究中心武汉430074 重庆大学土木工程学院重庆400045

由于内部材料的分层,钢-混组合梁整体竖向温度梯度分布不均匀,温度场求解困难且模拟精度和效率不理想。该文以傅里叶热传导定律为理论基础,推导了钢-混组合梁的一维日照温度场数值计算通用模型,采用逐次超松弛迭代法进行求解;通过一个钢... 详细信息

由于内部材料的分层,钢-混组合梁整体竖向温度梯度分布不均匀,温度场求解困难且模拟精度和效率不理想。该文以傅里叶热传导定律为理论基础,推导了钢-混组合梁的一维日照温度场数值计算通用模型,采用逐次超松弛迭代法进行求解;通过一个钢-混组合梁数值案例,对比分析了该方法与COMSOL的计算精度和效率;基于某大跨度斜拉桥的温度健康监测数据,验证了该方法对于日温度时程和全截面竖向温度梯度仿真的精度,并将竖向温度梯度的仿真结果与我国桥梁规范进行了对比。结果表明:该方法计算精度与物理场仿真软件保持一致,计算效率提升了78.3%,并能准确模拟大跨度斜拉桥钢-混组合梁的竖向温度分布,为大跨度斜拉桥钢-混组合梁温度效应的计算提供了强有力工具。

关键词：一维日照温度场高效数值模型逐次超松弛迭代法钢-混组合梁傅里叶热传导定律

Al含量对激光沉积(CoCrFeNi)-Al高熵合金晶粒形貌的影响

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热加工工艺 2024年第16期53卷 106-112页

作者：王文慧唐延川王友星万能华东交通大学材料科学与工程学院江西南昌330013

激光沉积技术有望成为制备高熵合金的理想方法,但其制备的高熵合金易产生粗大柱状晶组织,限制了其在高熵合金制备中的广泛应用。利用激光沉积制备了(CoCrFeNi)1-xAlx(x=0,0.10,0.15,0.20)高熵合金,研究了不同Al含量下激光沉积(CoCrFeNi)... 详细信息

激光沉积技术有望成为制备高熵合金的理想方法,但其制备的高熵合金易产生粗大柱状晶组织,限制了其在高熵合金制备中的广泛应用。利用激光沉积制备了(CoCrFeNi)1-xAlx(x=0,0.10,0.15,0.20)高熵合金,研究了不同Al含量下激光沉积(CoCrFeNi)1-xAlx高熵合金物相及晶粒形貌的演变规律,利用差热分析法对不同Al含量下高熵合金的凝固行为进行了分析。结果表明:随Al含量的增加,激光沉积(CoCrFeNi)1-xAlx高熵合金物相由面心立方(FCC)单相转变为FCC和体心立方(BCC)双相结构,不同Al含量下高熵合金中BCC相含量分别为3vol%(x=0.10)、24vol%(x=0.15)和52vol%(x=0.20);激光沉积高熵合金组织形貌也随Al含量增加由粗大柱状晶转变为细长晶粒,晶粒尺寸由116μm(x=0)显著降低至40μm(x=0.20)。这主要是由于Al含量的增加可降低(CoCrFeNi)1-xAlx高熵合金形核过冷度(ΔTN),并提高合金的生长限制因子(Q),从而产生更为显著的成分过冷,大幅促进了形核行为。

关键词：激光沉积高熵合金形核过冷度生长限制因子晶粒尺寸

A new localization theory of adaptive machining of near-net-shape blades

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Chinese Journal of Aeronautics 2021年第6期34卷 18-32页

作者： neng wan Xiaogang SHEN Zhiyong CHANG Zezhong C.CHEN Department of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontrealQuebec H3G IMSCanada

In the fabrication of aero-engine blades,a great deal is gained when massive material removal is avoided at the end of the process,and as little as possible material is left on the blade *** to the uncertainty of pre-process,the billet shapes are ***,the near-net-shape billet doesn’t cover the blade design surface to be ***,blade localization is necessary for these billets before the *** conventional localization methods,the design surface’s location focused on guaranteeing enough material to be ***,because the to-becut surface is in near-net and free-form shape,it is difficult to find a valid localized surface model to generate the tool *** from the localized surface is taken as rigid in previous investigation,it is allowed to deviate from the design surface no more than the tolerance *** term of this principle,the tolerance band is utilized to promote localization ability.A series of optimization models with different priorities is established to avoid the abandonment expensive blade ***,with the experiments performed on the near-net-shape blades,the blade localization theory and the promotion of localization ability are verified.

关键词： Blade localization Curvature constraint Machining surface Near-net-shape blade Tolerance constraint

基于卷积神经网络和交叉模型交叉模态方法的钢框架两阶段损伤识别研究

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工业建筑 2024年第1期54卷 123-129页

作者：万能黄民水朱宏平武汉工程大学土木工程与建筑学院武汉430073 华中科技大学土木与水利工程学院武汉430074

在结构损伤识别领域中,交叉模型交叉模态方法(CMCM)在求解含噪声的损伤识别问题时,受到系数矩阵不稳定的影响,往往导致损伤识别结果的精度下降。为了解决这一问题,提出了一种两阶段的损伤识别方法,旨在减少CMCM方法系数矩阵的冗余方程,... 详细信息

在结构损伤识别领域中,交叉模型交叉模态方法(CMCM)在求解含噪声的损伤识别问题时,受到系数矩阵不稳定的影响,往往导致损伤识别结果的精度下降。为了解决这一问题,提出了一种两阶段的损伤识别方法,旨在减少CMCM方法系数矩阵的冗余方程,提高CMCM方法的计算性能和噪声鲁棒性。首先,在第一阶段,通过卷积神经网络(CNN)进行结构损伤定位,以消除CMCM方法系数矩阵的冗余方程。其次,在第二阶段,求解已缩减的CMCM系数矩阵方程,得到更准确的损伤识别结果。通过数值和试验研究,验证了所提出的两阶段损伤识别方法的有效性,与传统的CMCM方法相比,所提方法在求解含噪声的损伤识别问题时,显著提高了损伤识别精度。

关键词：结构损伤识别交叉模型交叉模态卷积神经网络两阶段方法

Spatial Pattern Evolution and Casual Analysis of County Level Economy in Changsha-Zhuzhou-Xiangtan Urban Agglomeration, China

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Chinese Geographical Science 2014年第5期24卷 620-630页

作者： DONG Minghui ZOU Bin PU Qiang wan neng YANG Lingbin LUO Yanqing Department of Geography Hunan University of Arts and Science Department of Geomatics and Remote Sensing Central South University Department of Geography University of Utah Department of Geography Northeast Normal University

In order to evaluate whether or not the county units′ economy in the Changsha-Zhuzhou-Xiangtan(Chang-Zhu-Tan) Urban Agglomeration was growing as expected, this study analyzed the spatial economy pattern at county-level by using the Exploratory Spatial Data Analysis(ESDA) method. In this process, the global Moran′s I and local Getis-Ord G*i indexes were employed to analyze indicators including per capita GDP and three industrials(i.e. primary, secondary and tertiary industry) from 2000 to 2010. The results show that: 1) the county units′ economy in the Chang-Zhu-Tan Urban Agglomeration has exhibited a strong spatial autocorrelation and an accelerated integration trend since 2008(Moran′ s I increased from 0.26 to 0.56); 2) there is a significant difference in economy development between the northern and southern county units in the Chang-Zhu-Tan Urban Agglomeration: the hotspot zone with high economic level was formed among the northern county units whereas the coldspot zone with low economic level was located in the southern areas. This difference was caused primarily by the increasingly prominent economic radiation effect of Changsha ′upheaval′; 3) town density, secondary industry, and the integration policy are the major contributors driving the evolution of the spatial economy pattern in the Chang-Zhu-Tan Urban Agglomeration.

关键词： spatial autocorrelation spatial heterogeneity urban agglomeration county-level economy Changsha-Zhuzhou-Xiangtan (Chang-Zhu-Tan), China

Efficient photocatalytic hydrogen evolution coupled with benzaldehyde production over 0D Cd_(0.5)Zn_(0.5)S/2D Ti_(3)C2 Schottky heterojunction

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Journal of Advanced Ceramics 2022年第7期11卷 1117-1130页

作者： Junnan TAO Mingyuan wanG Guiwu LIU Qinqin LIU Lei LU neng wan Hua TANG Guanjun QIAO School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSchool of Electrical Science and EngineeringSoutheast UniversityNanjing 210096China School of Environmental Science and Engineering Qingdao UniversityQingdao 266071China

Converting water into hydrogen fuel and oxidizing benzyl alcohol to benzaldehyde simultaneously under visible light illumination is of great significance,but the fast recombination of photogenerated carriers in photocatalysts seriously decreases the conversion ***,a novel dual-functional 0D Cd_(0.5)Zn_(0.5)S/2D Ti_(3)C2 hybrid was fabricated by a solvothermally in-situ generated assembling *** Cd_(0.5)Zn_(0.5)S nano-spheres with a fluffy surface completely and uniformly covered the ultrathin Ti_(3)C2 nanosheets,leading to the increased Schottky barrier(SB)sites due to a large contact area,which could accelerate the electron–hole separation and improve the light *** optimized Cd_(0.5)Zn_(0.5)S/Ti_(3)C2 hybrid simultaneously presents a hydrogen evolution rate of 5.3 mmol/(g·h)and a benzaldehyde production rate of 29.3 mmol/(g·h),which are~3.2 and 2 times higher than those of pristine Cd_(0.5)Zn_(0.5)S,*** the multiple experimental measurements and the density functional theory(DFT)calculations further demonstrate the tight connection between Cd_(0.5)Zn_(0.5)S and Ti_(3)C2,formation of Schottky junction,and efficient photogenerated electron–hole *** paper suggests a dual-functional composite catalyst for photocatalytic hydrogen evolution and benzaldehyde production,and provides a new strategy for preventing the photogenerated electrons and holes from recombining by constructing a 0D/2D heterojunction with increased SB sites.

关键词： Cd_(0.5)Zn_(0.5)S Ti_(3)C2 photocatalysis hydrogen benzaldehyde Schottky heterojunction

Effect of fertilizer and water content on N_2O emission from three plantation soils in south China

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Journal of Environmental Sciences 2005年第6期17卷 970-976页

作者： LI Zhi-an ZOU Bi XIA Han-ping DING Yong-zhen TAN wan-neng MA Zhen-rong South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China

The effects of fertilizers and water content on N2O emission were studied using the three most typical plantation soils. Soil incubations were performed and fertilization and water content treatments were designed. At 25% of saturated water content（SWC）, N2O emissions from the soil treated with urea, KNO3, （NH4）2 SO, and KH2 PO, were compared at application rates of 0, 100, 200, 300 and 500 kg/hm2. At 80% of SWC, similar experiments were carried out but at only one application rate（500 kg/hm^2）. N2O emissions at various water contents（20%, 35%, 50%, 65%, 80% and 100% of SWC） were studied. At low water content（25% of SWC）, neither nitrogen nor phosphorus（or potassium） fertilizers led to a high level of N2O emission, which generally ranged from 2.03 to 29.02 μg/（m^2·h）. However, at high water content（80% SWC）, the fertilizers resulted in much greater N2O emission irregardless of soil tested. The highest N2O emission rates after 24 h of water addition were 1233 lag/（ m^2 ·h） for S. superba soil, 1507 lag/（m^2 · h） for P. elliottii soil and 1869 lag/ （m^2 h） for A. mangium soil respectively. N2O emission from soils treated with urea, （NH4）2SO, and KH2PO, immediately dropped to a low level but steadily increased to a very high level for the soil treated with KNO3. High NO3^- content was a basis of high level of N2O emission. N2O emission rates from soils peaked shortly after flooding, rapidly dropping to a very low level in soil from non-legume plantations, but lasting for a relatively long period in soil from legume plantations. When soil water content increased equaling to or higher than 65%, the accumulated N2O emission over a period of 13 d ranged from 20.21-29.78 mg/m^2 for S. superba, 30.57-70.12 mg/m^2 for P. elliottii and 300.89-430.51 mg/m^2 for A. mangium. The critical water content was 50% of SWC, above which a high level of N2O emission could be expected, and below which very little N2O emissions were detected. The results suggest that, at low water content（

关键词： N2O plantation south China Acacia mangium Pinus elliottii Schima superba