This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carbora...This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carboranyl radicals.Such hypervalent boron radicals are generated by a visible-light-promoted Pd(O)/Pd(I)pathway.They are useful intermediates and can be trapped by disulfides and phenylselenyl chloride for the convenient construction of B-S/Sebonds.展开更多
In this paper, we briefly introduce the history of the Defense Advanced Research Projects Agency(DARPA) Grand Challenge programs with particular focus on the 2012 Robotics Challenge. As members of team DRC-HUBO, we pr...In this paper, we briefly introduce the history of the Defense Advanced Research Projects Agency(DARPA) Grand Challenge programs with particular focus on the 2012 Robotics Challenge. As members of team DRC-HUBO, we propose different approaches for the Rough-Terrain task, such as enlarged foot pedals and a transformation into quadruped walking. We also introduce a new gait for humanoid robot locomotion to improve stability performance, called the Ski-Type gait. We analyze the stability performance of this gait and use the stability margin to choose between two candidate step sequences, Crawl-1 and Crawl-2. Next, we perform a force/torque analysis for the redundant closedchain system in the Ski-Type gait, and determine the joint torques by minimizing the total energy consumption. Based on the stability and force/torque analysis, we design a cane length to support a feasible and stable Crawl-2 gait on the HUBO2 humanoid robot platform. Finally, we compare our experimental results with biped walking to validate the SkiType gait. We also present our team performance in the trials of the Robotics Challenge.展开更多
Cortex Moutan (Paeonia suffruticosa Andr.) is a common traditional Chinese medicine and has been widely used in clinic for 2000 years in China. As sources for this crude drug are always mixed with other species, many ...Cortex Moutan (Paeonia suffruticosa Andr.) is a common traditional Chinese medicine and has been widely used in clinic for 2000 years in China. As sources for this crude drug are always mixed with other species, many cultivars on herbal market may lead to quality instability. Multi-component quantitative analysis is an efficient method to reflect chemical profiles of herb medicine and is always taken as the main method for quality evaluation. So, the aim of this work is to develop analytical method to quantify paeonol, paeoniflorin, gallic acid, oxypaeoniflorin, benzoylpaeoniflorin and paeonolide in Cortex Moutan (CM) to evaluate the chemical qualities of CM from different species or cultivars. Besides, we also study the intestinal absorption characteristics of paeonol and paeoniflorin for further pharmacological evaluation. In the present study, all of the standard markers were performed on an Ecosil C18 (250 mm × 4.6 mm, 5 μM, Lubex Co., Guangzhou, China) with linear gradient elution of 0.2% formic acid water and acetonitrile. The proposed method was applied to analyze 50 batches of samples with acceptable linearity (R2, 0.9995 - 0.9999), precisions (RSD, 0.47% - 2.08%), repeatability (RSD, 039% - 2.63%), stability (RSD, 0.52% - 2.45%), and recovery (RSD, 0.72% - 3.03%) of the six compounds. Furthermore, the Hierarchical Cluster Analysis was applied to classify the 50 samples based on contents of the six compound markers. The results obtained from multi-component quantification of CM clearly indicated that CM originated from P. suffruticosa and P. ostii presented different chemical properties, and that samples from the two materials could be gathered into one branch, respectively, while CM sourced from cultivars of P. suffruticosa showed great variety on chemical quality. The results from Hierarchical Cluster Analysis implied that the established method could be used as a powerful tool for the quality evaluation of CM. The intestinal absorption study indicated that the intestinal absorption activities for paeoniflorin and paeonol showed an increasing absorption with time. Paeonol had lower absorption rate (6.69% - 15.93%) than that of paeoniflorin (19.0% - 30.70%). As a result, the established method is suitable for the quality evaluation of CM. The results of intestinal absorption characteristics of paeonol and paeoniflorin offer an insight for pharmacological evaluation and clinical efficacy research of CM.展开更多
基金supported by a grant from the Southern University of Science and Technology.
文摘This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carboranyl radicals.Such hypervalent boron radicals are generated by a visible-light-promoted Pd(O)/Pd(I)pathway.They are useful intermediates and can be trapped by disulfides and phenylselenyl chloride for the convenient construction of B-S/Sebonds.
文摘In this paper, we briefly introduce the history of the Defense Advanced Research Projects Agency(DARPA) Grand Challenge programs with particular focus on the 2012 Robotics Challenge. As members of team DRC-HUBO, we propose different approaches for the Rough-Terrain task, such as enlarged foot pedals and a transformation into quadruped walking. We also introduce a new gait for humanoid robot locomotion to improve stability performance, called the Ski-Type gait. We analyze the stability performance of this gait and use the stability margin to choose between two candidate step sequences, Crawl-1 and Crawl-2. Next, we perform a force/torque analysis for the redundant closedchain system in the Ski-Type gait, and determine the joint torques by minimizing the total energy consumption. Based on the stability and force/torque analysis, we design a cane length to support a feasible and stable Crawl-2 gait on the HUBO2 humanoid robot platform. Finally, we compare our experimental results with biped walking to validate the SkiType gait. We also present our team performance in the trials of the Robotics Challenge.
文摘Cortex Moutan (Paeonia suffruticosa Andr.) is a common traditional Chinese medicine and has been widely used in clinic for 2000 years in China. As sources for this crude drug are always mixed with other species, many cultivars on herbal market may lead to quality instability. Multi-component quantitative analysis is an efficient method to reflect chemical profiles of herb medicine and is always taken as the main method for quality evaluation. So, the aim of this work is to develop analytical method to quantify paeonol, paeoniflorin, gallic acid, oxypaeoniflorin, benzoylpaeoniflorin and paeonolide in Cortex Moutan (CM) to evaluate the chemical qualities of CM from different species or cultivars. Besides, we also study the intestinal absorption characteristics of paeonol and paeoniflorin for further pharmacological evaluation. In the present study, all of the standard markers were performed on an Ecosil C18 (250 mm × 4.6 mm, 5 μM, Lubex Co., Guangzhou, China) with linear gradient elution of 0.2% formic acid water and acetonitrile. The proposed method was applied to analyze 50 batches of samples with acceptable linearity (R2, 0.9995 - 0.9999), precisions (RSD, 0.47% - 2.08%), repeatability (RSD, 039% - 2.63%), stability (RSD, 0.52% - 2.45%), and recovery (RSD, 0.72% - 3.03%) of the six compounds. Furthermore, the Hierarchical Cluster Analysis was applied to classify the 50 samples based on contents of the six compound markers. The results obtained from multi-component quantification of CM clearly indicated that CM originated from P. suffruticosa and P. ostii presented different chemical properties, and that samples from the two materials could be gathered into one branch, respectively, while CM sourced from cultivars of P. suffruticosa showed great variety on chemical quality. The results from Hierarchical Cluster Analysis implied that the established method could be used as a powerful tool for the quality evaluation of CM. The intestinal absorption study indicated that the intestinal absorption activities for paeoniflorin and paeonol showed an increasing absorption with time. Paeonol had lower absorption rate (6.69% - 15.93%) than that of paeoniflorin (19.0% - 30.70%). As a result, the established method is suitable for the quality evaluation of CM. The results of intestinal absorption characteristics of paeonol and paeoniflorin offer an insight for pharmacological evaluation and clinical efficacy research of CM.
