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Unit-cell design for two-dimensional phase-field simulation of microstructure evolution in single-crystal Ni-based superalloys during solidification

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Progress in Natural Science:Materials International 2017年第6期27卷 678-686页

作者： Dongjia Cao Na ta Lijun Zhang State Key Lab of Powder Metallurgy Central South University Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) Ruhr-University Bochum

Phase-field simulation serves as an effective tool for quantitative characterization of microstructure evolution in single-crystal Ni-based superalloys during solidification nowadays. The classic unit cell is either limited to γdendrites along crystal orientation or too ideal to cover complex morphologies for γ dendrites. An attempt to design the unit cell for two-dimensional(2-D) phase-field simulations of microstructure evolution in single-crystal Ni-based superalloys during solidification was thus performed by using the MICRESS(MICRostructure Evolution Simulation Software) in the framework of the multi-phase-field(MPF) model,and demonstrated in a commercial TMS-113 superalloy. The coupling to CALPHAD(CALculation of PHAse Diagram) thermodynamic database was realized via the TQ interface and the experimental diffusion coefficients were utilized in the simulation. Firstly, the classic unit cell with a single γ dendrite along crystal orientation was employed for the phase-field simulation in order to reproduce the microstructure ***, such simple unit cell was extended into the cases with two other different crystal orientations, i.e., and . Thirdly, for crystal orientations, the effect of γ dendritic orientations and unit cell sizes on microstructure and microsegregation was comprehensively studied, from which a new unit cell with multiple γdendrites was proposed. The phase-field simulation with the newly proposed unit cell was further performed in the TMS-113 superalloy, and the microstructure features including the competitive growth of γ dendrites,microsegregation of different solutes and distribution of γ′ grains, can be nicely reproduced.

关键词： Ni-based superalloys Solidification Microstructure Phase-field simulation Unit cell

Effects of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 on the peroxidase-catalyzed oxidation of 2-naphthol

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Journal of Environmental Sciences 2013年第7期25卷 1431-1440页

作者： Ivanec-Goranina Rūta Kulys Juozas Department of Chemistry and Bioengineering Faculty of Fundamental Sciences Vilnius Gediminas Technical University Institute of Biochemistry Vilnius University

The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.

关键词： oxidation peroxidase biosurfactant critical micelle concentration

以城市命名的大道规划设计分析——以揭阳大道为例

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交通工程 2024年第2期24卷 68-74页

作者：塔建胡劲松广州市交通规划研究院有限公司广州510030

“大道”是道路通名等级划分中的最高级别,以城市名称命名的“大道”是1座城市的代表路,具有唯一性.本文首先给出了“大道”的界定,提出城市大道是1座城市的名片,能加深人们的归属感与认同感,提高城市知名度,并应执行高标准规划设计要求... 详细信息

“大道”是道路通名等级划分中的最高级别,以城市名称命名的“大道”是1座城市的代表路,具有唯一性.本文首先给出了“大道”的界定,提出城市大道是1座城市的名片,能加深人们的归属感与认同感,提高城市知名度,并应执行高标准规划设计要求;以揭阳市揭阳大道为例,分析了其规划定位和交通功能定位;最后从交通提速、慢行提升、景观提质等方面提出揭阳大道精细化、人性化、品质化设计方案.相关分析及设计理念可供类似项目参考借鉴.

关键词：道路命名大道揭阳大道定位规划设计

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反刍动物益生菌制剂的研究进展

饲料工业 2024年第17期45卷 18-23页

作者：余小红刘晗璐赵德辉塔娜中国农业科学院草原研究所内蒙古呼和浩特010010 河北科技师范学院动物科技学院河北省特色动物种质资源挖掘与创新重点实验室河北秦皇岛066004 赤峰学院农学院蒙东农业生态保护与动植物资源开发利用实验室内蒙古赤峰024000 南京农业大学动物科技学院消化道微生物研究室江苏南京210095

一直以来,人们认为反刍动物因其强大的瘤胃发酵系统,对外源微生物具有较强的缓冲作用。但随着微生物学技术的发展,越来越多的研究证明外源添加益生菌制剂可调节微生物群落组成,维护瘤胃微环境动态平衡,影响挥发性脂肪酸的产生和氮的流动... 详细信息

一直以来,人们认为反刍动物因其强大的瘤胃发酵系统,对外源微生物具有较强的缓冲作用。但随着微生物学技术的发展,越来越多的研究证明外源添加益生菌制剂可调节微生物群落组成,维护瘤胃微环境动态平衡,影响挥发性脂肪酸的产生和氮的流动,促进饲料的消化利用,最终提高反刍动物生产性能,目前反刍动物生产中益生菌制剂的应用也日益广泛。此外,益生菌还可以减轻宿主动物应激反应、增强机体抗氧化能力,从而对反刍动物的生产性能以及生物习性产生影响。文章综述了益生菌影响反刍动物生产性能的各种直接和间接因素,为益生菌在反刍动物生产领域的应用提供参考。

关键词：益生菌反刍动物饲料添加剂瘤胃微生物消化

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脉冲多普勒雷达重频参数的一种序贯估计方法

现代雷达 2024年第2期46卷 103-111页

作者：尚文秀袁硕拓世英刘章孟国防科技大学电子科学学院湖南长沙410073

针对逐脉冲序贯重频参数估计的场景,引入了评估变量控制对脉冲的缓存,对受漏脉冲和干扰脉冲等数据噪声污染的脉冲列进行了较高精度的参数估计;进一步对缓存区间内的脉冲采用试探整除的方法,对脉冲多普勒雷达截获脉冲列中重频切换的跳变... 详细信息

针对逐脉冲序贯重频参数估计的场景,引入了评估变量控制对脉冲的缓存,对受漏脉冲和干扰脉冲等数据噪声污染的脉冲列进行了较高精度的参数估计;进一步对缓存区间内的脉冲采用试探整除的方法,对脉冲多普勒雷达截获脉冲列中重频切换的跳变时刻进行了跟踪检测。仿真实验验证了文中所提的重频参数序贯估计方法相较于传统重频参数估计方法在序贯估计场景下的有效性和优越性。

关键词：脉冲多普勒雷达重频参数估计序贯估计

基于超声-光声多模态成像仪器的骨结构及成分高分辨率表征方法

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仪器仪表学报 2024年第6期45卷 177-187页

作者：谢强李博艺杨春山韩帅他得安复旦大学信息科学与工程学院上海200433 复旦大学工程与应用技术研究院生物医学工程技术研究所上海200433

早期诊断和治疗骨质疏松症能显著降低骨折风险。骨组织物理结构和生化成分的影像学检查对骨质疏松症的诊断具有重要意义。为了克服基于射线的骨骼健康检查技术存在电离辐射,无法表征骨组织生化成分等问题,本文设计了一套超声-光声多模... 详细信息

早期诊断和治疗骨质疏松症能显著降低骨折风险。骨组织物理结构和生化成分的影像学检查对骨质疏松症的诊断具有重要意义。为了克服基于射线的骨骼健康检查技术存在电离辐射,无法表征骨组织生化成分等问题,本文设计了一套超声-光声多模态成像仪器。该仪器由波长实时可调的激光器、多模时序控制器、超声数据采集与控制器、高速数据交换与传输模块组成,利用时分复用和异步成像策略原位采集超声和光声信号,结合高分辨率成像算法获得骨组织的超声-光声影像。松质骨仿体和牛松质骨的离体试验以及手指关节在体试验结果表明,所提出的超声-光声多模态成像仪器在骨质疏松症的诊断中具有潜在的应用价值,为全面评价骨骼健康的临床研究奠定了基础。

关键词：骨质疏松超声-光声成像仪骨结构及成分表征高分率骨成像

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Management of Vulnating Esophageal Foreign Bodies in Burkina Faso

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第2期13卷 135-148页

作者： Ibrahima Diallo Aboubacar Gouéta Alseny Camara Assoumi Anatou Biga Mama Brigitte Ouoba Edi Emmanuel Martial Nao Moustapha Sérémé Bertin Priva Ouédraogo Yvette Marie Chantal Gyébré Abdoulaye Keita Alpha Oumar Diallo ENT and HNS Department Yalgado Ouédraogo University Hospital Ouagadougou Burkina Faso ENT and HNS Department Bogodogo University Hospital Ouagadougou Burkina Faso ENT and HNS Department Tengandogo University Hospital Ouagadougou Burkina Faso ENT and HNS Department Conakry University Hospital Conakry Guinea

Introduction: Esophageal foreign bodies (EFB) are a diagnostic and therapeutic emergency because of the serious complications they can cause. Aim: This paper aimed to study the vulnating esophageal foreign bodies in the ENT and Head and Neck Surgery departments of the Yalgado Ouedraogo and Bogodogo University Hospital. Methodology: This was an analytic cross-sectional study with retrospective data collection over 10 years (2012-2021). Results: We collected 91 cases of vulnating esophageal foreign bodies, i.e. 9.1 cases/year (4.7%). The mean age of the patients was 14 ± 19 years. The sex ratio was 1.6. The circumstances of occurrence were dominated by accidental ingestion of vulnating esophageal foreign bodies (98.9%). The average time to consultation was 7.5 hours. Dysphagia was the dominant symptom (64.8%). Cervico-thoracic radiography found dual contour radiopaque images in 71.4%. Esophagoscopy with rigid tube was performed in 97.8%. The average time for extraction of the vulnating esophageal foreign bodies was 8 hours. Vulnerating esophageal foreign bodies were non-organic in 84.6%. The button cell represented 64.8%. Their location was cervical in 61.5% intraoperatively. The lesion assessment found ulcerative lesions in 42.9% (p Conclusion: Vulnating esophageal foreign bodies are relatively frequent in our ENT practice. Although their diagnosis is often easy, their treatment is still difficult and requires multidisciplinary management. Thus, for us, prevention remains the first effective weapon.

关键词： Foreign Bodies Esophagus Vulnerable Management Sequelae

Necrotizing Pneumonia and Conservative Treatment: A Case Report and Review of the Literature

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Open Journal of Respiratory Diseases 2024年第3期14卷 69-76页

作者： Pedro Rogerio Magalhães Braga Eduarda Kipper Beck Carolina de Mello Viera Cecília Gatti Wolff Laura Gazal Passos Guilherme Bastos de Mello Luis Felipe Pilar Gomes Giacomo Farias Tramontin taíse Rosa de Carvalho Department of Internal Medicine Hospital So Lucas da PUCRS Porto Alegre Brazil School of Medicine Pontifcia Universidade Catlica do Rio Grande do Sul Porto Alegre Brazil Department of Radiology Hospital So Lucas da PUCRS Porto Alegre Brazil

We present a case of necrotizing pneumonia in an 87-year-old man without severe respiratory instability. Clinical suspicion arose due to the need for supplementary oxygen and persistent fever during treatment for community-acquired pneumonia. The diagnosis was confirmed by chest computed tomography. Although necrotizing pneumonia typically requires major surgical intervention upon diagnosis, we chose conservative management with antimicrobials and chest drainage alone. The patient experienced significant improvement and resolution of pneumonia with conservative management.

关键词： Respiratory Tract Infections Lung Disease Bacterial Pneumonia

Sorption of Water-Extractable Organic Carbon in Various Clay Subsoils: Effects of Soil Properties

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Pedosphere 2016年第1期26卷 55-61页

作者： Trung ta NGUYEN Petra MARSCHNER School of Agriculture Food and Wine The University of Adelaide

Clay-rich subsoils are added to sandy soils to improve crop yield and increase organic carbon （C） sequestration; however, little is known about the influence of clay subsoil properties on organic C sorption and desorption. Batch sorption experiments were conducted with nine clay subsoils with a range of properties. The clay subsoils were shaken for 16 h at 4 ℃with water-extractable organic C （WEOC, 1 224 g C L-1） from mature wheat residue at a soil to extract ratio of 1：10. After removal of the supernatant, the residual pellet was shaken with deionised water to determine organic C desorption. The WEOC sorption was positively correlated with smectite and illite contents, cation exchange capacity （CEC） and total organic C, but negatively correlated with kaolinite content. Desorption of WEOC expressed as a percentage of WEOC sorbed was negatively correlated with smectite and illite contents, CEC, total and exchangeable calcium （Ca） concentrations and clay content, but positively correlated with kaolinite content. The relative importance of these properties varied among soil types. The soils with a high WEOC sorption capacity had medium CEC and their dominant clay minerals were smectite and illite. In contrast, kaolinite was the dominant clay mineral in the soils with a low WEOC sorption capacity and low-to-medium CEC. However, most soils had properties which could increase WEOC sorption as well as those that could decrease WEOC sorption. The relative importance of properties increasing or decreasing WEOC sorption varied with soils. The soils with high desorption had a low total Ca concentration, low-to-medium CEC and low clay content, whereas the soils with low desorption were characterised by medium-to-high CEC and smectite and illite were the dominant clay minerals. We conclude that WEOC sorption and desorption depend not on a single property but rather a combination of several properties of the subsoils in this study.

关键词： cation exchange capacity, clay mineral illite, kaolinite smectite