24 research outputs found

    《桑树坪纪事》剧本

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    Unity3D机器人焊接焊缝自动提取及轨迹规划与仿真

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    为了发挥虚拟现实的良好视觉优势和避免机器人示教繁琐操作,利用三角网格特征提取算法实现自动提取焊缝,基于Unity3D虚拟仿真环境,实现轨迹规划并进行机器人焊接仿真。以ABB IRB4600-60/2.05机器人为例,搭建机器人焊接的虚拟仿真系统。根据特征点的特性采用基于边和基于面相结合的特征提取算法,实现焊接仿真特征边线的提取,进行三次样条曲线插值拟合后获取机器人焊接轨迹,通过机器人逆运动学求解机器人各关节运动的角度,进行机器人运动轨迹规划。实验结果表明,使用该系统的用户可以利用此特征提取算法有效的实现机器人自动焊接仿真,避免人工示教的复杂操作。福建省高端装备制造协同创新中心福建省科技重大专项(2015HZ0002-1

    Design and Research of Optical Structure for the Visible Light in the Coaxal

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    在激光技术的应用中,常常要对激光束实现某种实用空间界面的准确定位和聚焦。聚焦和定位的困难在于能够透过红外或紫外辐射的光学材料往往无法透过可见光,使得各种激光束的聚焦光斑的空间定位设计成为困难,阻碍了激光技术的应用。为此,结合课题的科研工作,研究设计了二种性能各异的同轴可见光导引光路结构,并在医疗临床应用中,获得了满意的效果。The main difficulty of pointing out of the visible light in the coaxal is can be transmission the optical material of infrared radiation but often unable to transmission.Given the space fixed position of focusing facula of lasers beam in difficulty.Same of the kinds of coaxied light system of point out are designed,through the clinical application of the exact of fixed position and quick and continues variable and the safe operation is reliable.The devolopings and applications of whole mechine system of the a way of technology is supplied for.福建省科技计划项目(No.2001I017)资

    Artificial local magnetic field inhomogeneity enhances T2 relaxivity

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    磁性探针作为分子影像技术中的磁共振成像(MRI)造影剂在医学诊断中发挥着重要作用。为满足实际诊断中的准确性和精确性要求,科研工作者们长期致力于发展高性能的MRI造影剂以降低高剂量的使用带来的潜在风险。该文章指出了探针聚集体中局域磁场不均匀性是影响T2弛豫效能的关键因素。该文章首次利用磁场不均匀性因素阐明了单个探针和它们聚集体的MRI造影剂之间的相互关系,将可能成为弥补探针聚集体的造影剂理论的空白,并为发展新型高效的MRI造影剂提供重要参考。 该论文共同第一作者为博士后周子健和博士生田蕊,通讯作者为陈小元教授和聂立铭博士,部分工作得到我校物理学系王瑞方教授和化学化工学院高锦豪教授的支持。【Abstract】Clustering of magnetic nanoparticles (MNPs) is perhaps the most effective, yet intriguing strategy to enhance T2 relaxivity in magnetic resonance imaging (MRI). However, the underlying mechanism is still not fully understood and the attempts to generalize the classic outersphere theory from single particles to clusters have been found to be inadequate. Here we show that clustering of MNPs enhances local field inhomogeneity due to reduced field symmetry, which can be further elevated by artificially involving iron oxide NPs with heterogeneous geometries in terms of size and shape. The r2 values of iron oxide clusters and Landau–Lifshitz–Gilbert simulations confirmed our hypothesis, indicating that solving magnetic field inhomogeneity may become a powerful way to build correlation between magnetization and T2 relaxivity of MNPs, especially magnetic clusters. This study provides a simple yet distinct mechanism to interpret T2 relaxivity of MNPs, which is crucial to the design of high-performance MRI contrast agents.This work was supported by the National Science Foundation of China (81571744 and 81601489), the National Basic Research Program of China (863 Program 2015AA020502), the Fundamental Research Funds for the Central Universities (20720170065), the Science Foundation of Fujian Province (No. 2014Y2004), and by the Intramural Research Program (IRP), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH). 研究工作得到了国家自然科学基金委、国家高技术研究发展计划863项目、福建省重大研发平台项目和美国NIH Intramural Research Program的资助

    Artificial local magnetic field inhomogeneity enhances T2 relaxivity

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    磁性探针作为分子影像技术中的磁共振成像(MRI)造影剂在医学诊断中发挥着重要作用。为满足实际诊断中的准确性和精确性要求,科研工作者们长期致力于发展高性能的MRI造影剂以降低高剂量的使用带来的潜在风险。该文章指出了探针聚集体中局域磁场不均匀性是影响T2弛豫效能的关键因素。该文章首次利用磁场不均匀性因素阐明了单个探针和它们聚集体的MRI造影剂之间的相互关系,将可能成为弥补探针聚集体的造影剂理论的空白,并为发展新型高效的MRI造影剂提供重要参考。 该论文共同第一作者为博士后周子健和博士生田蕊,通讯作者为陈小元教授和聂立铭博士,部分工作得到我校物理学系王瑞方教授和化学化工学院高锦豪教授的支持。【Abstract】Clustering of magnetic nanoparticles (MNPs) is perhaps the most effective, yet intriguing strategy to enhance T2 relaxivity in magnetic resonance imaging (MRI). However, the underlying mechanism is still not fully understood and the attempts to generalize the classic outersphere theory from single particles to clusters have been found to be inadequate. Here we show that clustering of MNPs enhances local field inhomogeneity due to reduced field symmetry, which can be further elevated by artificially involving iron oxide NPs with heterogeneous geometries in terms of size and shape. The r2 values of iron oxide clusters and Landau–Lifshitz–Gilbert simulations confirmed our hypothesis, indicating that solving magnetic field inhomogeneity may become a powerful way to build correlation between magnetization and T2 relaxivity of MNPs, especially magnetic clusters. This study provides a simple yet distinct mechanism to interpret T2 relaxivity of MNPs, which is crucial to the design of high-performance MRI contrast agents.This work was supported by the National Science Foundation of China (81571744 and 81601489), the National Basic Research Program of China (863 Program 2015AA020502), the Fundamental Research Funds for the Central Universities (20720170065), the Science Foundation of Fujian Province (No. 2014Y2004), and by the Intramural Research Program (IRP), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH). 研究工作得到了国家自然科学基金委、国家高技术研究发展计划863项目、福建省重大研发平台项目和美国NIH Intramural Research Program的资助

    品牌联合营销:演绎1+1>2的传奇

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    《孙子兵法》有云:兵者,诡道也!常言商场如战场,众品牌是奋勇杀敌的将士,营销则有如排兵作战,集中体现各品牌的战术思想和经营智慧。如今注意力成为一种稀缺资源,众商家纷纷热衷于各式眼花缭乱,甚至耸人听闻的营销手段,以期在激烈的竞争中占据有利的位置。在众多花样翻新的营

    武汉东湖表层沉积物有机物污染状况

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    2000年12月在武汉东湖采集5个表层沉积物样品,采用气-质联用分析了其中的有机污染物,以探讨东湖沉积物受有机物污染的程度。共检出有机物180种,其中环境优先控制污染物和美国EPA筛选的内分泌干扰物35种,有机污染严重程度为:水果湖区>郭郑湖南湖区>郭郑湖北湖区

    武汉东湖表层沉积物有机物污染状况

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    2 0 0 0年 12月在武汉东湖采集了 5个表层沉积物样品 ,采用气 -质联用分析了其中的有机污染物 ,以探讨东湖沉积物受有机物污染的程度 .共检出有机物 180种 ,其中环境优先控制污染物和美国EPA筛选的内分泌干扰物 35种 .有机污染严重程度为 :水果湖区 >郭郑湖南湖区 >郭郑湖北湖区

    乙炔基雌二醇对稀有鮈鲫肾脏的毒性效应

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    研究了环境相关水平的人工合成雌激素乙炔基雌二醇对稀有鮈鲫肾脏的慢性毒性.结果表明,当暴露浓度达到20ng·L^-1以上时,稀有鮈鲫的肾脏指数显著增大,具有明显的剂量效应关系,肾脏组织表现出明显的病理学特征,肾小管内腔扩大,严重出血,有的被一种嗜曙红物质所填充,肾小管壁的管状上皮细胞严重肿大并出现退化和坏死。肾小管之间的间隙组织大量出现.肾脏的肿大导致了畸形个体出现.因此乙炔基雌二醇不仅可以导致鱼类的内分泌干扰效应,而且可以引发严重的肾脏组织损伤;鱼的肾脏指数和肾脏病理学变化可以作为评价环境雌激素类化合物毒性效应的敏感指标;由于稀有鮈鲫对雌激素类物质具有较高的敏感性,将其应用为污染监测的模型动物也是可能的
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