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31.
A new analytical method of designing two-aspherical-mirror anastigmats was developed and applied to searching solution groups of soft X-ray microscopes of a large misalignment tolerance. The two-mirror anastigmat configurations were expressed by a practical variable related to pupil obstruction limiting the system throughput. Axial coma and other aberrations caused by a slight decenter of the system were then formulated to represent sensitivity to misalignment. These formulations enabled a global survey of solution groups as demonstrated by a designing example of soft X-ray microscopes with a magnification m = −1/50, which resulted in four solutions more insensitive to misalignment than a standard Schwarzschild optics in the soft X-ray region. Some solutions were also found to have much larger fields of view suitable for high resolution imaging as confirmed by computer ray tracing.  相似文献   
32.
The problem considered is that of determining the shape of aplane acoustically sound-soft obstacle from the knowledge ofthe far-field pattern for one time-harmonic incident field.An iterative procedure is proposed based on two boundary integralsrepresenting the incident field and the far-field pattern, respectively.Numerical examples are included which show that the proceduregives accurate numerical approximations in relatively few iterations.  相似文献   
33.
合肥同步辐射软X射线显微术研究   总被引:1,自引:0,他引:1  
谢行恕  徐向东 《物理》1996,25(2):104-111
合肥国家同步辐射实验室首期建设的光束线之一用于软X射线显微成像研究。实验站现已装置初型的扫描透射X射线显微镜,并正在进行亲一代的扫描显微建设,同时还使同步辐射光进行接触软X射线呈微成像研究,并对选取的一些生物样品进行了成像试验。本文介绍了合肥同步辐射光源上软X射线显微术实验线站的建设及完成的一些实验结果。  相似文献   
34.
介绍了在软X-射线显微术研究领域中有重要应用的Si_3N_4薄膜窗口的实验室制作方法,并形成一套独特制备工艺,Si_3N_4薄膜窗口的研制成功推动了我国软X射线显微术研究的发展。  相似文献   
35.
软珊瑚Sinularia sp.中次生代谢产物的结构鉴定   总被引:1,自引:0,他引:1  
细胞毒性;软珊瑚Sinularia sp.中次生代谢产物的结构鉴定  相似文献   
36.
用上升液滴法测定了2-乙基己基膦酸单(2-乙基己基)酯-正辛烷从硝酸介质中萃取镁、钙、锌、镍、铜和铅等二价金属离子的正向初始速率,建立了速率方程,计算出正向萃取反应的速率常数、活化能及活化熵,首次将软硬酸碱规则与金属溶萃取速率常数关联。结果表明,在萃取机理相同时,萃取速率常数的大小与金属离子的软硬酸碱标度一致,即萃取过程中,作为酸的被萃取金属离子,其硬度越大,萃取速率常数亦越大,萃取反应的活化能…  相似文献   
37.
王磊  刘静 《化学教育》2019,40(20):1-12
镓是第一个根据化学元素周期律预言并在自然界中证实的元素,是室温下电导率和热导率均为最大的液态物质,镓在电子工业中得到了广泛应用,被誉为电子工业“脊梁”。近十几年来,镓的更多应用潜力被发掘出来,在电子工业、散热、增材制造、柔性机器、生物医学等领域均有重要的应用前景。  相似文献   
38.
针对现有极化码软输出译码器存在的高资源消耗与低资源效率,设计了一种快速低复杂度软取消(Fast Reduced Complexity Soft-Cancelation,Fast-RCSC)译码算法及其译码器硬件架构。Fast-RCSC算法对内部特殊结点进行完整计算,在减少译码周期的同时仍有较好译码性能。基于不同特殊结点公式之间存在相似性,进而通过对引入的特殊结点模块进行计算结果复用以及计算模块分时复用,减少特殊结点模块资源消耗。通过共用存储单元以及对不足存储单元数据宽度的数据进行合并,降低存储资源消耗。在华润上华(Central Semiconductor Manufacturing Corporation,CSMC)180nm工艺下综合结果表明,设计的译码器在码长为1024的情况下,面积为2.92mm2,资源效率为245.2Mbps/mm2,相比现有软输出译码器有不同程度的提升。  相似文献   
39.
Artificial intelligent actuators are extensively explored for emerging applications such as soft robots, human-machine interfaces, and biomedical devices. However, intelligent actuating systems based on synthesized polymers suffer from challenges in renewability, sustainability, and safety, while natural polymer-based actuators show limited capabilities and performances due to the presence of abundant hydrogen-bond lockers. Here this study reports a new hydrogen bond-mediated strategy to develop mimosa-inspired starch actuators (SA). By harnessing the unique features of gelatinization and abundant hydrogen bonds, these SA enable high-sensitivity and multi-responsive actuation in various scenarios. The non-gelatinized SA can be irreversibly programmed into diverse shapes, such as artificial flowers, bowl shapes, and helix structures, using near-infrared light. Furthermore, the gelatinized SA exhibit reversibly multi-responsive actuation when exposed to low humidity (10.2%), low temperature (37 °C), or low-energy light (0.42 W cm−2). More importantly, the SA demonstrate robust applications in smart living, including artificial mimosa, intelligent lampshade, and morphing food. By overcoming the hydrogen-bond lockers inherent in natural polymers, SA open new avenues for next-generation recyclable materials and actuators, bringing them closer to practical applications.  相似文献   
40.
Flexible sensing technologies that play a pivotal role in endowing robots with detection capabilities and monitoring their motions are impulsively desired for intelligent robotics systems. However, integrating and constructing reliable and sustainable flexible sensors with multifunctionality for robots remains an everlasting challenge. Herein, an entirely intrinsic self-healing, stretchable, and attachable multimodal sensor is developed that can be conformally integrated with soft robots to identify diverse signals. The dynamic bonds cross-linked networks including the insulating polymer and conductive hydrogel with good comprehensive performances are designed to fabricate the sensor with prolonged lifespan and improved reliability. Benefiting from the self-adhesiveness of the hydrogel, strong interfacial bonding can be formed on various surfaces, which promotes the conformable integration of the sensor with robots. Due to the ionic transportation mechanism, the sensor can detect strain and temperature based on piezoresistive and thermoresistive effect, respectively. Moreover, the sensor can work in triboelectric mode to achieve self-powered sensing. Various information can be identified from the electrical signals generated by the sensor, including hand gestures, soft robot crawling motions, a message of code, the temperature of objects, and the type of materials, holding great promise in the fields of environmental detection, wearable devices, human-machine interfacing, and robotics.  相似文献   
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