Preliminary study on quantitative susceptibility mapping via single-scan spatiotemporally encoded MRI

磁共振成像技术（MRI）以核磁共振（NMR）原理为基础，可以提供一种无损伤手段来探测体内结构。平面回波成像（EPI）只需一次激发就可获取整幅图像，但在强磁场或者不均匀场中对磁化率伪影非常敏感，不适合用来获取相位图像。单扫描时空编码（SPEN）方法可以很好地解决这一问题，它对磁场不均匀具有天生的免疫力，并且在均匀场下可以提供与EPI方法类似质量的图像。定量磁化率成像（QSM）以相位信息为基础，是科学研究和临床应用的一个热点问题。本文将单扫描SPEN技术应用到局部相位像研究中，对促进QSM更深层次和更广泛的应用具有重要意义。本文的主要研究成果有： 一、首先对定量磁化率成像原理进行了简要介绍，接着...Magnetic resonance imaging (MRI) which is based on the nuclear magnetic resonance (NMR) can provide a no damaged means to detect structure in vivo. Echo planar imaging (EPI) has the ability to acquire a whole image in a single-scan, but it is sensitive to susceptibility artifacts when it is operated in high or inhomogeneous magnetic field. Therefore, EPI is usually not suitable for phase imaging. ...学位：工学硕士院系专业：物理与机电工程学院_电磁场与微波技术学号：1982011115285

LED Lighting Design of Underground Parking Lots Based on DILAUX

目前由于汽车的广泛普及,对城市的地下车库照明提出了更多的要求,但随着新一代照明光源lEd照明技术进一步的发展与完善,使得地下车库照明有了更节能、更环保、更经济的可能。在dIlAuX中建模57x33.3M2的中型地下车库,并利用dIlAuX计算软件对地下车库的lEd照明进行模拟、计算、优化,不断的调整灯具位置以及灯具间隔来到达最佳的照明效果,通过实景分析来探讨lEd在地下车库照明领域应用的可行性及其应用前景,并为地下车库照明提供一种设计上的借鉴。More requirements for the light system of civil underground parking lot lighting are concerned since cars are wildly-used nowadays.And it becomes possible to make the light system of underground parking lot more energy-saving,more environmental friendly and more economic as the new generation of LED technology gets more and more developed and improved.DILAUX is a kind of lighting calculation software,and it is used to model an underground parking lot with a medium 57 × 33.3m2and some simulations,calculations,and optimization on the LED light of the parking lot are also done by DILAUX.Therefore,constantly adjust locations and intervals of the lighting fixtures to achieve the optimal results.Furthermore,the feasibilities and application prospects of LED lighting applications in the underground parking lot field can also be explored through the real analysis.Overall,it shows an example to design the light system for civil underground parking lots.国家自然科学基金(61301009); 福建省重大科技项目资助(2006H0092); 福建省自然科学基金计划资助项目(2013J01252

Light Distribution Design and Simulation of LED for High Uniformity Illumination of Desk Lamp

针对台灯照明的高均匀性要求,设计一个自由曲面透镜对lEd光源进行二次光学配光。根据非成像光学理论,在已知入射光强分布与所需配光效果的前提下,建立关于透镜自由曲面面型的偏微分方程,并采用相应的数值解法,得到自由曲面面型数据。通过在建模软件rHInOCErOS中建立光学透镜的模型,并在TrACEPrO中进行光学仿真,得出仿真结果,验证此设计方法的可行性。According to high uniformity requirements of desk lamp lighting, a free curved surface lens is de-signed to perform the secondary light distribution of light emitting diode(LED) light source.Based on the theory ofnon-imaging optics, at the condition of known incident light intensity distribution and required light distribution effect,partial differential equations related to the shape of free curved surface are established.And corresponding numericalvalue algorithm is adopted to obtain the data of the shape of free curved surface.The models of optical lens are builtthrough simulation software Rhinoceros.And optical simulation is performed in Tracepro.The simulation results areobtained to verify the feasibility of the design method.福建省重大科技项目资助(2006H0092

定量磁化率成像重建方法及其应用

磁共振成像(MRI)中,相位图像包含丰富的组织磁化率变化信息,获取相位图像不需要额外的扫描时间.组织中的顺磁性物质会影响组织磁化率差异,从而导致局部磁场不均匀.对组织内顺磁性物质的定量有利于许多脑血管疾病和神经系统疾病的诊断,但利用局部相位信息重建组织磁化率分布是一个不适定逆问题,目前仍然有许多问题亟待解决.该文着重介绍定量磁化率成像(QSM)的原理、重建方法及其在MRI中的应用.国家自然科学基金资助项目(81171331,11174239);中央高校基本业务费资助项目(2010121101

钐钴合金材料、钐钴合金粉末及其制备方法及钐钴基磁体

本发明涉及一种钐钴合金材料，其化学原子计量式为Sm(Co1‑a‑b‑c‑dFeaCubZrcTMd)z，TM为Mn、Cr、V、Ti、Sc、Nb、Ta、Mo、W中的至少一种，其中0≤a≤0.25，0≤b≤0.15，0≤c≤0.04，0＜d≤0.15，6.8≤z≤8.5。本发明还涉及一种钐钴合金粉末及其制备方法及钐钴基磁体

高温度稳定性永磁材料及其应用

本发明公开了一种高温度稳定性永磁材料及其应用，所述永磁材料的微观结构包括强磁性相和具有自旋相变的磁性相，所述强磁性相和所述具有自旋相变的磁性相相互隔离，且所述强磁性相饱和磁化强度温度系数绝对值小于0.02％-℃。本发明通过包含强磁性相和具有自旋相变的磁性相的永磁材料来获得正矫顽力温度系数，使低矫顽力温度系数的获得更具有目的性、规律性和通用性；同时，本发明利用重稀土元素与过渡金属的反铁磁性耦合特性来调节磁体的剩磁温度系数，解决了现有技术中低矫顽力温度系数系数和低剩磁温度系数难以同时获得的技术难题

新疆扶桑绵粉蚧疫情的传入及扑灭概况[J]

本文概述了扶桑绵粉蚧近年在新疆传入扩散的情况。并根据扶桑绵粉蚧在新疆的发生及危害特点，总结了将其扑灭所采取的综合技术措施和经验，以供其他扶桑绵粉蚧发生地区参考