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排序方式: 共有1226条查询结果,搜索用时 33 毫秒
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Malay Patra Larissa S. Eichenberger Gregor Fischer Jason P. Holland 《Angewandte Chemie (International ed. in English)》2019,58(7):1928-1933
Monoclonal antibodies (mAbs), immunoglobulin fragments, and other proteins are important scaffolds in the development of radiopharmaceuticals for diagnostic immuno‐positron emission tomography (immuno‐PET) and targeted radioimmunotherapy (RIT). Conventional methods for radiolabelling proteins with metal ions such as 68Ga, 64Cu, 89Zr, and 90Y require multi‐step procedures involving pre‐purification, functionalisation with a chelate, and subsequent radiolabelling. Standard coupling chemistries are time‐consuming, difficult to automate, and involve synthesis, isolation, and storage of an intermediate, new molecular entity (the conjugated mAb) whose biochemical properties can differ from those of the parent protein. To circumvent these issues, we developed a photoradiochemical approach that uses fast, chemoselective, light‐induced protein modification under mild conditions with novel metal‐ion‐binding chelates derivatised with aryl azide (ArN3) groups. Experiments show that one‐pot photochemical conjugation and radiolabelling of formulated mAbs can be achieved in <20 min. 相似文献
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高能X射线工业CT扫描运动控制系统设计 总被引:1,自引:0,他引:1
分析了高能X射线工业CT扫描运动控制系统的作用,提出了扫描运动控制系统的组成方案。控制系统由工业控制计算机、计数卡、控制卡、伺服驱动器、伺服电机、工作平台、光栅和控制软件组成。研究了在Windows驱动程序模式(WDM)下,控制系统设备驱动程序的组成。以运动控制卡为例,研究了开发控制系统设备驱动程序的方法,并分析了设备驱动程序和用户程序交互的过程。通过编写WDM驱动程序,实现了对高能X射线工业CT扫描运动系统的实时控制。实验结果表明,开发的扫描运动控制系统,可靠性和实时性满足要求。 相似文献
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提出利用快速扫描光学延迟线(Rapid Scanning Optical Delay Line,RSOD)作为光学相干层析成像(Optical Coherence Tomography,OCT)系统的相位调制器,并采用正弦驱动方式(谐振扫描)来提高扫描频率,进而实现高频相位调制的方法.介绍了基于RSOD相位调制器的干涉信号包络解调方法,分析了大振镜低频率线性驱动、小振镜高频线性驱动和大振镜高速正弦驱动三种实施方案对OCT性能的影响,并针对谐振扫描方案中轴向扫描的非线性提出了图像畸变定量校正的方法.结果表明:RSOD大振镜谐振扫描的模式能够兼顾系统成像速度、成像范围以及系统信噪比的要求,是一种行之有效的相位调制方法. 相似文献
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Dev Raj Alok Kumar Rohit Kumar Singh Abhishek Singh Bhadouria A.S.K. Sinha Deepak Dwivedi 《Current Opinion in Electrochemistry》2022
As the application of electrocatalyst continues to expand, envisaging the hidden mechanisms occurring at various length scale affecting the catalytic efficiency became important. To enhance the stability of electrocatalyst and reduce the cost, it is of paramount importance to reveal the active site's dynamics (using in situ techniques for getting the real-time information) which directly affect the reactions such as oxygen evolution reaction, hydrogen evolution reaction, and so on. Since such reactions are crucial for many engineering and scientific applications, in situ characterization techniques are required, which could capture such reactions happening at a different length and time scale. This article analyzes the recent progress made in the field of electrocatalyst's characterization using in situ neutron techniques. The article also paves the future path and has delineated the future challenges involved in multiscale correlative techniques (e.g., neutron techniques in the combination of synchrotron or microscopic techniques) used for getting the multiscale (atomic to micrometer range) mechanistic information about the electrocatalyst's working and degradation. 相似文献
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Dr. Zhibo Liu Daniel Chao Dr. Ying Li Prof. Dr. Richard Ting Jihyoon Oh Prof. Dr. David M. Perrin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3924-3928
Organotrifluoroborates solvolyze in water at rates that vary over five orders of magnitude. The negative logarithm of the solvolytic rate constant, pk(B?F), correlates exceptionally well with the pKa of the analogous carboxylic acid (R2=0.984). This unforeseen correlation may be of predictive value for several applications including Suzuki–Miyaura cross‐coupling reactions and the design of 18F‐organotrifluoroborate radioprosthetic groups. 相似文献
160.
Hans Vanrompay Armand Bch Johan Verbeeck Sara Bals 《Particle & Particle Systems Characterization》2019,36(7)
One of the emerging challenges in the field of 3D characterization of nanoparticles by electron tomography is to avoid degradation and deformation of the samples during the acquisition of a tilt series. In order to reduce the required electron dose, various undersampling approaches have been proposed. These methods include lowering the number of 2D projection images, reducing the probe current during the acquisition, and scanning a smaller number of pixels in the 2D images. A comparison is made between these approaches based on tilt series acquired for a gold nanoparticle. 相似文献