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Microwave-assisted Solid-phase Synthesis, Biological Evaluation and Molecular docking of Angiotensin I-converting Enzyme Inhibitors

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Chemical Research in Chinese Universities 2012年第1期28卷 108-113页

作者： SUN Yang1, HUAng da-wei1, LI Xiao-hui1, HU Jian-en2 and XIU Zhi-long1 1. School of Life Science and Biotechnology, dalian University of Technology, dalian 116024, P. R. China 2. School of Food Engineering, dalian Ocean University, dalian 116023, P. R. China dalian Univ Technol Sch Life Sci & Biotechnol Dalian 116024 Peoples R China dalian Ocean Univ Sch Food Engn Dalian 116023 Peoples R China

Short peptides based on the tripeptides, Leu-Arg-Pro and Leu-Lys-Pro, were synthesized by microwave assisted solid-phase synthesis method, in order to make a search for potential inhibitors for angiotensin I-converting enzyme（ACE） with minimum side effects in the treatment of hypertension. One peptide with the sequence Leu-Arg-Pro-Phe-Phe shows the strongest inhibition towards ACE with an IC50 value of 0.26 μmol/L in vitro. The study of structure-activity relationship shows that the introduction of a bulky group into the N-terminal of this series of inhibitors may enlarge steric hindrance, resulting in the poor inhibitory activity towards ACE. The inhibitory activity decreased in turn when L-Pro, d-Pro or Ac6c was at the C-terminal respectively. The binding interaction between each of these inhibitors and testicular ACE（tACE） was performed by molecular docking. The results suggest that Leu-Arg-Pro-Phe-Phe mainly occupied the S1 subsite of tACE, and made contact with tACE via seven H-bonds. It appeared that the site on the peptide that bound with tACE was influenced by the configuration of the amino acid, L or d-form, at the C-terminal of the peptide.

关键词： Angiotensin I-converting enzyme Peptide inhibitor Molecular docking Microwave-assisted solid-phasesynthesis

A SIMPLE SMOOTH EXACT PENALTY FUNCTION FOR SMOOTH OPTIMIZATION PROBLEM

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Journal of Systems Science & Complexity 2012年第3期25卷 521-528页

作者： Shujun lian liansheng ZHAng College of Operations and Management Qufu Normal University department of Mathematics Shanghai University

For smooth optimization problem with equMity constraints, new continuously differentiable penalty function is derived. It is proved exact in the sense that local optimizers of a nonlinear program are precisely the optimizers of the associated penalty function under some nondegeneracy assumption. It is simple in the sense that the penalty function only includes the objective function and constrained functions, and it doesn＇t include their gradients. This is achieved by augmenting the dimension of the program by a variable that controls the weight of the penalty terms.

关键词： Constrained optimization exact penalty function smooth penalty function.

Numerical simulation of the influences of sinker weight on the deformation and load of net of gravity sea cage in uniform flow

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Acta Oceanologica Sinica 2006年第3期25卷 125-137页

作者： LI Yucheng 1,2* , ZHAO Yunpeng 1 , GUI Fukun 1 , TEng Bin 1 , dOng Guohai 1 1. State Key Laboratory of Coastal and Offshore Engineering, dalian University of Technology, dalian 116024, China 2. R&d Center of Civil Engineering Technology, dalian University, dalian 116622, China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

A numerical model for determining fishing net configuration and load is developed, based on the lumped masses method. The model is used to analyze the influences on the net of gravity sea cage by different sinker weights in uniform flow. The net of gravity sea cage is simulated under different current velocities and sinker weights. In order to verify the validity of the numerical results, model test results made by Lader and Enerhaug are cited and compared with the numerical ones. The results of numerical simulation agree well with the experimental ones and the agreement is within an error range of 13% under different velocities and sinker weights. The numerical results indicate that increasing the sinker weight can effectively reduce the net deformation, but the total drag force on the net will increase accordingly. Results will give references for better knowledge of the hydrodynamic behavior of gravity sea cage.

关键词： sea cage numerical simulation lumped mass method sinker weight

design and research of RF system for 10 MeV compact cyclotron

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 225-230页

作者： dong Li (1) TongNing Hu (2) KaiFeng Liu (1) Jun Yang (1) 1. College of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Department of Electronics and Information Engineering Huazhong University of Science and Technology Wuhan 430074 China

A 10 MeV compact cyclotron (CYCHU-10) has been developing in Huazhong University of Science and Technology (HUST). The RF system includes a 10 kW RF power generator and a resonance cavity. There is no automatic frequency tuning equipment in the cavity due to space limitations, so the generator must search and track the cavity resonant frequency. Ad9850 synthesizer is used to generate RF signal in the experimental prototype, and a fine sinusoidal waveform around 99 MHz is obtained with the method of picking up a special aliased signal from the synthesizer's output, and the output power level can be set by regulating the resistor connected to the Pin 'Rset'. The final stage amplifier based on tetrode operates in the grounded cathode configuration, and the schematic of the tetrode circuit is illustrated. The method of searching the resonant frequency is discussed in detail. For the sake of a compact and robust structure, the resonance cavity will adopt non-uniform characteristic impedance coaxial structure, and the magnet surface electroplated with copper will be used as dummy dees. The precise shapes and dimensions of the cavity are designed and simulation results are carried out in this paper. The distributions of electromagnetic field are illustrated by means of numerical calculation analysis, and the wooden model test is preformed as well.

关键词： compact cyclotron RF system Ad9850 tetrode resonance cavity

The　physical　implication　of　coda　amplitude　ratio　and　its　possible　application

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 441-448页

作者： Tian-Zhong Zhang (1) Yun-Sheng Ma (1) Rong-liang Huang (1) 1. Institute of Geophysics China Seismological Bureau 100081 Beijing China

ＴｈｅｐｈｙｓｉｃａｌｉｍｐｌｉｃａｔｉｏｎｏｆｃｏｄａａｍｐｌｉｔｕｄｅｒａｔｉｏａｎｄｉｔｓｐｏｓｓｉｂｌｅａｐｐｌｉｃａｔｉｏｎＴＩＡＮ－ＺＨＯＮＧＺＨＡＮＧ（张天中）ＹＵＮ－ＳＨＥＮＧＭＡ（马支生）ＲＯＮＧ－... 详细信息

ＴｈｅｐｈｙｓｉｃａｌｉｍｐｌｉｃａｔｉｏｎｏｆｃｏｄａａｍｐｌｉｔｕｄｅｒａｔｉｏａｎｄｉｔｓｐｏｓｓｉｂｌｅａｐｐｌｉｃａｔｉｏｎＴＩＡＮ－ＺＨＯＮＧＺＨＡＮＧ（张天中）ＹＵＮ－ＳＨＥＮＧＭＡ（马支生）ＲＯＮＧ－ＬＩＡＮＧＨＵＡＮＧ（黄蓉良）Ｉｎ...

关键词： coda amplitude ratio energy ratio coda Q mean free path seismic precursors

On the dynamics of the Singularly Perturbed Rational Maps

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Acta Mathematica Sinica,English Series 2010年第2期26卷 265-276页

作者： lian Rong dIng Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

In this paper, we study the dynamics of the family of rational maps fλ,（z） = zn - λ/zm, n ≥2, m ≥ 1,λ ∈ C. We construct an example of buried Sierpinski curve Julia set in this family. We also give an estimate ... 详细信息

关键词： Julia set Sierpinski curve bifurcation locus

The role of AVdR in linear cascade testing

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航空动力学报 2007年第6期22卷 933-944页

作者： Wing F.ng department of Mechanical Engineering Virginia Polytechnic Instituteand State University

Linear cascade testing plays an important role in the research and development of turbomachinery and is widely used over the *** ideal cascade model of a turbomachinery blade row is *** actual linear cascade testing,the flow through the test section converges due to the development of the boundary layer and secondary flow along the sidewall surfaces of the test *** velocity density ratio(AVdR) is adopted to account for the deviation of the tested cascade flow from the ideal 2d *** numerous published cascade works,the influence of AVdR on cascade performance is seen to be complicated with many affecting factors,such as those related to cascade/blade geometry and flow ***,controlling AVdR is limited by the facility ***,real blade-to-blade flow in turbomachines is usually associated with AVdR greater than unity due to limited span of blades between the hub and shroud such that cascade testing without reducing AVdR could be favored *** these facets add complexity and diversification to the *** current paper reviews previous studies and results on *** understanding on the role of AVdR and recommendations on how to deal with it in linear cascade testing are provided.

关键词：线性叶栅试验轴向速度密度比空气流动叶栅特性

Stable High-Energy density Super-Atom Clusters of Aluminum Hydride

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Chinese Journal of Chemical Physics 2012年第2期25卷 147-152,I0003页

作者： Ke-yan lian Yuan-fei Jiang de-hou Fei Wei Feng Ming-xing Jin da-jun ding Yi Luo Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China department of Theoretical Chemistry Royal Institute of TechnologyAlbaNovaS-106-91 StockholmSweden Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Tech-nology of ChinaHefei 230025China

With the concept of super-atom, first principles calculations propose a new type of super stable cage clusters AlnH3n that are much more energetic stable than the well established clusters, AlnHn＋2. In the new clusters, the aluminum core-frame acts as a super-atom with n vertexes and 2n A1-A1 edges, which allow to adsorb n hydrogen atoms at the top-site and 2n at the bridge-site. Using Al12H36 as the basic unit, stable chain structures, （Al12H36）m, have been constructed following the same connection mechanism as for （A1H3）n linear polymeric structures. Apart from high hydrogen percentage per molecule, calculations have shown that these new clusters possess large heat of formation values and their combustion heat is about 4.8 times of the methane, making them a promising high energy density material.

关键词： High-energy density Super-atom First principles Cluster of aluminum hydride

Synthesis and characterization of yttrium-aluminum-iron and yttrium-cerium-iron citric complexes

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Journal of Rare Earths 2008年第3期26卷 307-314页

作者： N. Petrova d. Todorovsky1 I. Mitov G. Tyuliev Faculty of Chemistry University of Sofia 1 J. Bourchier Blvd. Sofia 1164 Bulgaria Institute of Catalysis Bulgarian Academy of Sciences Acad. G. Bonchev Str. bl. 11 Sofia 1113 Bulgaria

Fe-, Y-Fe-Al- and Y-Ce-Fe- citrates were synthesized in ethylene glycol （EG） medium under conditions similar to those used in the polymerized complex method. Their elemental composition, IR,^ 13C and ^1H NMR, X-ray photoelectron and Mossbauer spectra were studied, and formulae describing their composition were proposed. The complexes contained EG bonded as adduct and ester with citric acid ligand and did not contain ligands with deprotonated alcoholic groups. The complexes consisted of agglomerated spheres, 0.7-3 μm in diameter. The local composition of the products was established by energy dispersive X-ray microanalysis. The comparison of the number of the ligands, their average electrical charge and the esterification degree of mono-, di- and trimetallic complexes proved the mixed-metal nature of the species studied. The thermal decomposition of the complexes was studied and a general scheme of the processes taking place was proposed. Highly crystalline, phase homogeneous YaFe4AlO12 was produced after heating the respective complex at 1000 ℃. Ce-doped yttrium-iron garnet, similarly prepared, contained traces of CeO2.

关键词： garnets polymerized complex method Mossbauer spectroscopy thermal analysis NMR-spectroscopy rare earths