Carbon-11 radiolabeled amines constitute a very important class of radioligands that are widely used for positron emission tomography (PET) imaging. Radiolabeling of amines is often achieved through radiomethylation u...Carbon-11 radiolabeled amines constitute a very important class of radioligands that are widely used for positron emission tomography (PET) imaging. Radiolabeling of amines is often achieved through radiomethylation using [11C]CH3I or [11C]CH3OTf under basic conditions in a strictly anhydrous environment. Functional groups such as hydroxyl and carboxyl groups that are often present in the molecules are normally base sensitive and require protection and deprotection, which substantially prolongs and complicates the radiolabeling process. Here we report a versatile approach to a series of C-11 radiolabeled amines prepared through reductive amination using [11C]formaldehyde. Using a variety of substrates bearing different functional groups, we demonstrate the general utility of this method. In contrast to conventional radiomethylation methods, the reductive amination using [11C]formaldehyde can be carried out in an aqueous environment relatively quickly without the need of protection of base-sensitive functional groups.展开更多
In modern facility agriculture,to improve the quality and efficiency of transplanting,the application of transplanting robots based on visual processing is becoming more and more widespread.In order to reduce the dama...In modern facility agriculture,to improve the quality and efficiency of transplanting,the application of transplanting robots based on visual processing is becoming more and more widespread.In order to reduce the damage to plants during the transplanting process and reduce the damage rate of plant stems,leaves and substrates,a transplanting method based on Kinect visual processing combined with an inclined transplanting manipulator was proposed.In the research,the Kinect visual processing was used to obtain and process the seedling height information and leaf edge information,and the working coordinate system of the transplanting manipulator was established and applied to plan the obstacle avoidance path.Combined with the oblique manipulator,the obstacle avoidance transplanting method was proposed.Through the structural design and force analysis of the seedling transplanting device,the key parameters that affect the transplanting quality were obtained,and the optimal transplanting performance parameters were obtained through experiments.In the experiment,with the aid of the Kinect vision processing system,the designed obstacle avoidance transplanting manipulator had a leaf damage degree of 4.70%,a stem bending rate of 16.67%,substrate integrity of 83.45%and a transplanting quality parameter of 87.36%.The time for a single seedling transplanting was(8.32±0.40)s.The experiment result proves that the obstacle avoidance transplanting method based on Kinect visual processing can effectively reduce the damage to seedlings when ensuring the transplanting efficiency.展开更多
文摘Carbon-11 radiolabeled amines constitute a very important class of radioligands that are widely used for positron emission tomography (PET) imaging. Radiolabeling of amines is often achieved through radiomethylation using [11C]CH3I or [11C]CH3OTf under basic conditions in a strictly anhydrous environment. Functional groups such as hydroxyl and carboxyl groups that are often present in the molecules are normally base sensitive and require protection and deprotection, which substantially prolongs and complicates the radiolabeling process. Here we report a versatile approach to a series of C-11 radiolabeled amines prepared through reductive amination using [11C]formaldehyde. Using a variety of substrates bearing different functional groups, we demonstrate the general utility of this method. In contrast to conventional radiomethylation methods, the reductive amination using [11C]formaldehyde can be carried out in an aqueous environment relatively quickly without the need of protection of base-sensitive functional groups.
基金supported by the National Natural Science Foundation of China(Grant No.51875175)the Natural Science Foundation of Henan(Grant No.202300410124)+1 种基金the Key Research and Development Program of Guangdong Province(Grant No.2019B020222004)the Innovation Scientists and Technicians Talent Projects of Henan Provincial Department of Education(Grant No.19HASTIT021).
文摘In modern facility agriculture,to improve the quality and efficiency of transplanting,the application of transplanting robots based on visual processing is becoming more and more widespread.In order to reduce the damage to plants during the transplanting process and reduce the damage rate of plant stems,leaves and substrates,a transplanting method based on Kinect visual processing combined with an inclined transplanting manipulator was proposed.In the research,the Kinect visual processing was used to obtain and process the seedling height information and leaf edge information,and the working coordinate system of the transplanting manipulator was established and applied to plan the obstacle avoidance path.Combined with the oblique manipulator,the obstacle avoidance transplanting method was proposed.Through the structural design and force analysis of the seedling transplanting device,the key parameters that affect the transplanting quality were obtained,and the optimal transplanting performance parameters were obtained through experiments.In the experiment,with the aid of the Kinect vision processing system,the designed obstacle avoidance transplanting manipulator had a leaf damage degree of 4.70%,a stem bending rate of 16.67%,substrate integrity of 83.45%and a transplanting quality parameter of 87.36%.The time for a single seedling transplanting was(8.32±0.40)s.The experiment result proves that the obstacle avoidance transplanting method based on Kinect visual processing can effectively reduce the damage to seedlings when ensuring the transplanting efficiency.
