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Pinacol Coupling Reactions Catalyzed by Active Zinc

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Chinese Chemical Letters 2005年第11期16卷 1459-1462页

作者： Hui ZHAO Wei deng Qing xiang GUO Department of Chemistry University of Science and Technology of China Hefei 230026

Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.

关键词： Pinacol coupling reaction active zinc carbonyl compounds electron transfer.

Improving the numerical stability of the MAGIC model

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Journal of Environmental Sciences 2001年第2期13卷 189-191页

作者： deng Yi- xiang CHEN Ji- ning HU Xue- tao Department of Envi ronment Sciences and Engineering T singhua University Bei jing 100084 China

MAGIC is one of the most widely used models for forecasting long-term acidification. The model's code, however, has been experiencing numerical instability, though this might not be widely known to the public users. The major instability comes from the analytical solution to two cubic equations for calculating SO42- concentration and the exchangeable fraction of Al on the soils. The mathematical algorithm for calculating the concentration of SO42- from a quadratic equation is also found instable. This paper is aimed at improving the instability above through proved numerical algorithms.

关键词： MAGIC model numerical instability

Fabrication of Monodisperse ＂Core-Satellite＂ Nanostructures by DNA-Programming： a Novel Class of Superstructured Building Blocks for Hierarchical Nanoassembly

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Chinese Journal of Chemical Physics 2013年第5期26卷 601-606,I0004页

作者： Yang Yang Xue Bai Ling-ling Fang Zhao-xiang deng CAS Key Laboratory of Soft Matter Chemistry & Collaborative Innovation Center of Suzhou NanoScience and Technology Department of Chemisto4 University of Science and Technology of ChinaHefei 230026 China

Monodisperse nanoparticle assembly with tunable structure, composition and properties can be taken as a superstructured building block for the construction of hierarchical nanostruc tures from the bottom up, which also represents a great challenge in nanotechnology. Here we report on a facile and controllable method that enables a high yield fabricatioa of uniform gold nanoparticle （AuNP） coresatellites with definable number （in average） of the satellite particles and tunable coretosatellite distance. The formation of the coresatellite nanostruc tures is driven by programmable DNAbasepairing, with the resulting nanocomplexes being isolatable via gel electrophoresis. By rationally controlling the DNA coverages on the core and shell particles, high production yields are achieved for the assembly/isolation process. As well, benefiting from a minimum DNA coverage on the satellite AuNPs, a strong affinity is observed for the asprepared coresatellites to get adsorbed on proteincoated graphene ox ide, which allows for a twodimensional hierarchical assembly of the coresatellite structures. The resulting hierarchical nanoassemblies are expected to find applications in various areas, including plasmonics, biosensing, and nanocatalysis. The method should be generalizable to make even more complicated and higherorder structures by making use of the structural programmability of DNA molecules.

关键词： Core-satellite DNA nanoassembly Graphene oxide Gold nanoparticle Hier-archical structure

Characteristic analysis of tetra-resistant genetically modified rice

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Journal of Integrative Agriculture 2018年第3期17卷 493-506页

作者： HU Wen-bin deng xiang-yang deng Xiao-xiang deng Li-hua XIAO You-lun HE Xing-jian FU Xi-qin XIAO Guo-ying Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 P.R.China State Key Laboratory of Hybrid Rice/Hunan Hybrid Rice Research Center Changsha 410125 P.R. China University of Chinese Academy of Sciences Beijing 100049 P.R.China Hunan Plant Protection Institute Hunan Academy of Agricultural Sciences Changsha 410125 P.R. China Sericultural Research Institute of Hunan Province Changsha 410125 P.R. China

In this study, the characteristic of three transformants named as B1C106-1, B1C106-2, and B1C106-3 were studied that carried three innate resistant genes Bph14, Bph15, and Xa23, and two enthetic resistant genes CrylCa# and Bar. The five resistant genes were all verified by PCR and the two enthetic genes were identified in single copy insertion by Southern blot. At tillering stage, the CrylC and PAT （phosphinothricin acetyl transferase） protein contents in leaf, sheath, and stem of T2 generation were in the similar pattern： leaf〉stem〉sheath, and showed significant difference （P〈0.01） among three organs. The average contents of CrylC protein in plant of B1C106-1, B1C106-2, and BIC106-3 were 12.95, 6.57, and 11.30 μg g-1, respectively, and showed significant difference （P〈0.01） among them. However, the average contents of PAT in plant of B1C106-1, B1C106-2, and B1C106-3 were 28.54, 27.66, and 28.02 pg g-1, respectively, and there were no significant difference among three transformants. The glufosinate tolerable concentration of three transformants of T3 generation reached at least 6 g L-1, and the mortality of rice leaf rollers were above 97.4% in 5 days after being fed with fresh transformants＇ leaves. The CrylC protein toxicity was also assessed by silkworms, and the mortality of silkworms feeding mulberry leaves smeared with Cry1C protein extracts of leaves of B1 C106-1, BIC106-2, and B1 C106-3 were 90, 67.8, and 87.8%, respectively, that were positive correlation （r=0.993） with CrylC protein contents in plant of three transformants. The three transformants also maintained high resistance to brown planthopper and bacterial blight as the original version. The above results indicate the tetra-resistant rice germplasm was well-developed by pyramiding innate and enthetic resistant genes in an elite line to provide with resistances of glufosinate, rice leaf roller, brown planthopper, and bacterial blight.

关键词： rice resistance glufosinate rice leaf roller brown planthopper bacterial blight

Robust adaptive precision motion control of tank horizontal stabilizer based on unknown actuator backlash compensation

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Defence Technology（防务技术） 2023年第2期20卷 72-83页

作者： Shu-Sen Yuan Wen-xiang deng Jian-Yong Yao Guo-Lai Yang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjingChina

Backlash nonlinearity inevitably exists in the actuator of tank horizontal stabilizer and has adverse effect on the system control performance,however,how to effectively eliminate its effect remains a pending *** solve this problem,a robust adaptive precision motion controller is presented in this paper to address uncertainties and unknown actuator backlash of tank horizontal *** controller handles the modeling uncertainties including parameter uncertainties and unmodeled disturbances by integrating adaptive feedforward compensation and continuous nonlinear robust *** on the backstepping method,a smooth backlash inverse model is constructed by combining the adaptive ***,the unknown backlash parameters of the system can be approximated through the parameter adaptation,and the impact of the actuator backlash nonlinearity is effectively compensated via the inverse operation,which can availably improve the tracking ***,the adaptive law can update the disturbance ranges of tank horizontal stabilizer online in real time,which enhances the feasibility in practical engineering ***,the stability analysis based on Lyapunov function shows that with the existence of unmodeled disturbances and unknown actuator backlash,the designed controller guarantees excellent asymptotic output tracking *** comparative results verify the effectiveness of the proposed control strategy.

关键词： Tank Horizontal stabilizer Adaptive control Robust control Backlash inverse

Accuracy Validation for Medical Image Registration Algorithms:a Review

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Chinese Medical Sciences Journal 2012年第3期27卷 176-181页

作者： Zhe Liu xiang deng Guang-zhi Wang Department of Biomedical Engineering Tsinghua UniversityBeijing 100084China Center for Medical Imaging Validation Corporate TechnologySiemens Ltd.ChinaBeijing 100102China

Accuracy validation is essential to clinical application of medical image registration techniques. Registration validation remains a challenging problem in practice mainly due to lack of 'ground truth'. In this paper, an overview of current validation methods for medical image registration is presented with detailed discussion of their benefits and drawbacks. Special focus is on non-rigid registration validation. Promising solution is also discussed.

关键词： non-rigid registration accuracy validation digital phantom

Differential amplification method for flow structures analysis of centrifugal pump between design and off-design points

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Journal of Central South University 2017年第6期24卷 1443-1449页

作者： ZHANG He-hui deng Sheng-xiang QU Ying-jie School of Energy Science and Engineering Central South UniversityChangsha 410083China Hunan M&W Energy Saving Tech.Co.Ltd. Changsha 410208China

The three-dimensional internal flow field of centrifugal pump is complex and variable with design parameters and operation conditions. The post-processing technique named differential amplification method was proposed for the comparison study of different flow structures. The full steady flow fields of an industrial centrifugal pump working on-design and off-design points were numerically investigated by solving Reynolds average Navier-Stokes equations together with a shear-stress transport(SST) k-? turbulence model. And the numerically predicted performance curves of the studied pump agree well with test measurement results. Compared with the flow flied on design point under the help of differential amplification method, the disturbance caused by interaction between blade and volute tongue is very obvious and it extends to the diffuser pipe on the working point with 0.8 times rated flux. While on the point with 1.2 times rated flux, the flow distribution in impeller region is roughly even and it flows more to the bottom section of the diffuser pipe. The above method was proved to be good at displaying the subtle secondary flow structure changes with a higher resolution effect relative to single isolated case observation, which helps the optimization decision-making from multiple design cases.

关键词： differential amplification computational fluid dynamics (CFD) flow structure centrifugal pump

Fabrication of micro pin fins on inclined V-shaped microchannel walls via laser micromilling

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Advances in Manufacturing 2022年第2期10卷 220-234页

作者： Da-xiang deng Jian Zheng Xiao-Long Chen Guang Pi Yong-Heng Liu School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhenShenzhen 518055GuangdongPeople's Republic of China Department of Mechanical and Electrical Engineering Xiamen UniversityXiamen 361005FujianPeople's Republic of China

A laser-micromilling process was developed for fabricating micro pin fins on inclined V-shaped microchannel walls for enhanced microchannel heat sinks.A pulsed nanosecond fiber laser was *** feasibility and mechanism of the formation of micro pin fins on inclined microchannel walls were investigated for a wide range of processing *** effects of the laser output power,scanning speed,and line spacing on the surface morphologies and geometric sizes of the micro-pin fins were comprehensively examined,together with the material removal *** pin fins with acute cone tips were readily formed on the V-shaped microchannel walls via the piling of recast layers and the downflow of re-solidified materials in the laser-ablation *** pin-fin height exhibited an increasing trend when the scanning speed increased from 100mm/s to 300 mm/s,and it decreased continuously when the line spacing increased from 5μm to 20μ*** optimal processing parameters for preparing micro pin fins on V-shaped microchannels were found to be a laser output power of 21 W,scanning speed of 100-300 mm/s,and line spacing of 2-5μ***,the V-shaped microchannels with micro pin fins induced a 7%-538%boiling heat-transfer enhancement over their counterpart without micro pin fins.

关键词： Laser micromilling Micro pin fins:Microchannels Inclined walls Laser ablation

Progress in Mechanism of Astragalus membranaceus and Its Chemical Constituents on Multiple Sclerosis

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Chinese Journal of Integrative Medicine 2023年第1期29卷 89-95页

作者： PENG Yong deng xiang YANG Shan-shan NIE Wei TANG Yan-dan Department of Neurology Affiliated First Hospital of Hunan Traditional Chinese Medical CollegeZhuzhouHunan Province412000China

The primary chemical components of Astragalus membranaceus include polysaccharides,saponins,flavonoids,and amino *** studies have shown that Astragalus membranaceus has multiple functions,including improving immune function and exerting antioxidative,anti-radiation,anti-tumor,antibacterial,antiviral,and hormone-like *** membranaceus and its extracts are widely used in clinical practice because they have obvious therapeutic effects against various autoimmune diseases and relatively less adverse *** sclerosis(MS)is an autoimmune disease of central nervous system(CNS),which mainly caused by immune disorder that leads to inflammatory demyelination,inflammatory cell infiltration,and axonal degeneration in the *** this review,the authors analyzed the clinical manifestations of MS and experimental autoimmune encephalomyelitis(EAE)and focused on the efficacy of Astragalus membranaceus and its chemical components in the treatment of MS/EAE.

关键词： Astragalus membranaceus chemical components multiple sclerosis experimental autoimmune encephalomyelitis immunoregulation