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Numerical simulation of soft palate movement and airflow in human upper airway by fluid-structure interaction method

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Acta Mechanica Sinica 2007年第4期23卷 359-367页

作者： Xiuzhen Sun Chi Yu Yuefang Wang Yingxi Liu State Key lab.of Struct.anal.for Ind.Equip.,Dalian University of Technology,Dalian 116024,China The Second Affiliated Hospital,Dalian Medical University,Dalian 116027,China State Key lab. of Struct. anal. for Ind. Equip. Dalian University of Technology Dalian China The Second Affiliated Hospital Dalian Medical University Dalian China

In this paper, the authors present airflow field characteristics of human upper airway and soft palate movement attitude during breathing. On the basis of the data taken from the spiral computerized tomography images of a healthy person and a patient with Obstructive Sleep Apnea-Hypopnea Syndrome （OSAHS）, three-dimensional models of upper airway cavity and soft palate are reconstructed by the method of surface rendering. Numerical simulation is performed for airflow in the upper airway and displacement of soft palate by fluid-structure interaction analysis. The reconstructed threedimensional models precisely preserve the original configuration of upper airways and soft palate. The results of the pressure and velocity distributions in the airflow field are quantitatively determined, and the displacement of soft palate is presented. Pressure gradients of airway are lower for the healthy person and the airflow distribution is quite uniform in the case of free breathing. However, the OSAHS patient remarkably escalates both the pressure and velocity in the upper airway, and causes higher displacement of the soft palate. The present study is useful in revealing pathogenesis and quantitative mutual relationship between configuration and function of the upper airway as well as in diagnosingdiseases related to anatomical structure and function of the upper airway.

关键词： Obstructive sleep apnea-hypopnea syndrome Upper airway Soft palate Three-dimensional finiteelement reconstruction Fluid-structure interaction Numerical simulation

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Major Phenolics in Yerba Mate Extracts (<i>Ilex paraguariensis</i>) and Their Contribution to the Total Antioxidant Capacity

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Food and Nutrition Sciences 2013年第8期4卷 154-162页

作者： Lorena deladino Aline Schneider Teixeira Mario Reta Antonio D. Molina García Alba S. Navarro Miriam N. Martino Centro de Investigación y desarrollo en Criotecnología de Alimentos (CIDCA CONICET-UNLP) La Plata Argentina Centro de Investigación y desarrollo en Criotecnología de Alimentos (CIDCA CONICET-UNLP) La Plata Argentina Facultad de Ingeniería Universidad Na- cional de La Plata (UNLP) La Plata Argentina. ICTAN Instituto de Ciencia y Tecnología de Alimentos y Nutrición CSIC José Antonio Novais 10 Madrid Spain lab. de separaciones analíticas División Química Analítica Fac. Cs. Exactas (UNLP) La Plata Argentina

Yerba mate (Ilex paraguariensis) is an indigenous crop which is highly consumed as an infusion in the South American subtropical forest. It has a high concentration of antioxidant substances, providing health benefits and helping to prevent diseases. The objectives of this work were to characterize an aqueous yerba mate extract by spectrophotometric and chromatographic (HPLC) methods and to study the effect of the freeze-drying process on the polyphenols profile and antioxidant activity, determined by a novel method. An aqueous extract was obtained and lyophilized to obtain a yerba mate powder with antioxidant properties. The extracts showed a high polyphenol content, determined by Folin-Ciocalteau and HPLC, and a high antioxidant activity towards the DPPH· radical and after the recently developed method of photochemiluminescence. A linear correlation was found between Folin-Ciocalteau and DPPH methods for lyophilized samples. HPLC analysis allowed determining antioxidant components like rutin, caffeine and chlorogenic acid. Lyophilization caused a decrease in total polyphenol content and antiradical activity of the extracts and this fact was mainly attributed to changes in the chlorogenic acid related compounds and rutin structures, after their photochemiluminescence data. The photoluminiscent method proves to be an advantageous approach for antioxidant capacity determination.

关键词： Yerba Mate Natural Antioxidants Freeze Drying DPPH HPLC PCL

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A Novel Pentadecanuclear Neodymium Cluster: Synthesis and Structure of [Nd_(15)(μ_4-tyr)_(10)(μ_3-OH)_(20)(μ_2-OH)_4(OH)_(10)(μ_2-H_2O)-(H_2O)_(10)][Na(ClO_4)_2]·61H_2O

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Chinese Chemical Letters 1998年第12期9卷 0-0,0-0页

作者： Rui Yao WANG Zhe Ming WANG Song GAO Tian Zhu JIN Zhi Da CHEN Chun Hua YAN Guang Xian XU (State Key lab.ratory of Rare Earth Material Chemistry and ApplicationsPeking UniverSity, Beijing 100871)Cun Heng HE (National Research Center for analysis of Dr State Key lab. Rare Earth Mat. C./A. Peking University Beijing 100871 China Natl. Res. Ctr. anal. Drugs/M. Beijing 100050 China

The title complex was synthesized by dissolving tyrosine (tyr) in an aqueous solution ofNd(ClO4)3 at NpH5, and its crystal stfucture was determined by X-ray diffraction methods. Thecomplex is a novel pentadecanuclear with the 15 Nd3+ ions connected by μ3-OH- ions. The tyrosineligands are all in their anionic form, and each coordinates to the neodymium ions via the nitrogenatom of the amino group and the two carboxyl oxygen atoms. The molecule a barrel structure.

关键词： Neodymium tyrosine pentadecanuclear cluster

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Asymmetric　Tetrahedral　Cadmium　Complex：Bis［triphenylphosphine］cadmium（Ⅱ）Diiodide

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Chinese Journal of Structural Chemistry 1996年第4期15卷 270-272页

作者： Gou Shao-Hua Lu Jian-Ping Zeng Qin-Dao You Xiao-Zeng(Coordination Chemistry Institute and State Key lab.rataory of Coordination Chemistry,Nanjing University, Hanjing 210093)Yu Kai-Bei(Chengdu Center of analysis and determination, Academia Sinica,Cheng Coordination Chemistry Institute State Key Lab. of Coord. Chemistry Nanjing University Nanjing 210093 Chengdu Ctr. anal. and determination Academia Sinica Chengdu 610051

The structure of the title complex, [Cd (PPh_3)_2I_2], was determined by X-ray diffraction with crystallographic data as follows: C_36H_30CdI_2P_2, Mr=890. 75, monoclinic, space group P2_1/a, a=18. 367(3), b=10. 300(3), c=19.339 (3) A, β=111. 68(1)°; V=3400(1) A￣3, Z=4, D_x= 1. 74 g/cm￣3, P=25. 5 cm￣(-1),F(000)=1720, R=0. 0470, R_w=0. 049. The coordination polyhedron of each Cd atom is a distorted tetrahedron consisting of two P atoms from two triphenylphosphine groups and two iodine anions. The molecule has no C_2 symmetry with two unequal Cd -P bonds due to the presence of the bulky size of triphosphine.

关键词： crystal structure Cd(Ⅱ) complex triphenylphosphine

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Structure of 7, 8, 17, 18-Tetrabromo-5,10,15, 20-Tetraphenylporphinatozinc(Ⅱ)

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Chinese Journal of Structural Chemistry 1997年第1期16卷 29-31页

作者： ZOU Jian--Zhong LI Ming XU Zheng YOU Xiao--Zeng(Coordination Chemistry Institute, State Key lab.ratory ofCoordination Chemistry, Nanjing University,Nanjing, 210093)YU Kai--Bei(Chengdu Ceder of analysis and Measurement, Academia Sinica, Chengdu 61004 Coordination Chemistry Institute State Key Lab. of Coord. Chemistry Nanjing University Nanjing 210093 China Chengdu Ctr. of anal./Measerment Academia Sinica Chengdu 610041 Taiwan

The crystal structure of 7, 8, 17, 18--tetrabromo--5, 10, 15, 20--Tetraphenylporphinatozinc (Ⅱ ) (ZnTPPBr 4. H2O ) was det ermined. The molecular far formula is C44H26Br4N4OZn, Mr= 1003. 7, trigonal, R3, a= 27. 325 (6) A, c= 12. 967(3) A, V=8384(4) A', Z=9, Dx= 1. 80 g/cm3, F(000) =4463, μ= 5. 27 *** molecular structure of 7, 8, 17, 18--tetrabromo--5, 10, 15, 20--tetraphenyl porphinatozinc (Ⅱ ) (ZnTPPBr4) shows that the macrocycle skeleton of the title compound isplanar. Due to the electron-withdrawing effect of the bromine atoms, the Zn--N bondsare inequal. In crystal lattice, the solvolytic water molecule is distributed *** oxygen atoms O, Oa and Ob of water form a equilateral triangle, two triangleoverlap together to form a regular hexagon. The water molecule occupies on each of sixapexes of the hexagon with equal probability.

关键词： crystal structure,tetrabromotetraphenylporphinato zinc (Ⅱ) complex

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STUDY　ON　REACTION　OF　（μ₃－CCO₂Et）CO₂M（CO）₈（CpMe）（M＝Mo，W）　WITH　Na₂［Fe（CO）₄］．SYNTHESIS　OF　TWO　KINDS　OF　THE　NOVEL　CLUSTERS　EtO₂CCFeCoM（CO）₈（CpMe）H　AND　（OCC）FeCoM（CO）₈（CpMe）

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Chinese Chemical Letters 1996年第4期7卷 381-384页

作者： Wu H.P. Ding E.R. Yin Y.Q. Huano X.Y. Yu K.B. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 Fuzhou Inst. on Structure of Matter Stn. Key Lab. of Structure Chemistry Fuzhou 350002 Chengdu Ctr. of anal. and Msrmt. Chinese Academy of Sciences Chengdu 610041

The reactions of dusters (μ3- CCO2Et)Co2M (CO)8(MeCp)[M = Mo(2a),W(2b)], derived from the reaction of (μ3-CCO2Et)Co3(CO)9 with Na[M(CO)3(MeCp)], with Na2[Fe(CO)4] in THF at reflux not only gave the expected metal fragment exchange products (μ3-CCO2Et) FeCoM (CO)6(Me-Cp )H [M=Mo(3a), W(3b)] but also produced the unexpected compounds (μ3-CCO)FeCoM (CO)5(MeCp) [M=MO(4a), W(4b)]. It is suggested that the formation of two kinds of compounds resulted from two competitive reactions of the intermediates [(μ3-CCO2Et) FeCo M(CO)8,(MeCp)] with 11+: the one is the Protonic reaction of the intermediate giving the cluster 3a,b; the another one is the intermolecular nucleophilic substitution reaction of the intermediate under the H+ catalytic action giving the cluster 4a,b.

关键词： CARBONYL CLUSTERS

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NUMERICAL SIMULATION OF ELASTIC WAVE PROPAGATION IN ANISOTROPIC MEDIA

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Acta Mechanica Solida Sinica 2000年第1期13卷 50-59页

作者： Zhang, JF Liu, TL Dalian Univ Technol State Key Lab Struct Anal Ind Equipment Dalian 116024 Peoples R China

A new numerical simulation algorithm is presented for the elastic wave propagation in heterogeneous anisotropic media. We make discretization of the computational domain by using triangular and quadrangular grids. The scheme is based on integral equilibrium at each node to simulate the elastic wave propagation in heterogeneous anisotropic media. The scheme is very flexible in dealing with arbitrary surface topography, inner openings, liquid-solid boundaries and irregular interfaces. Moreover, tho free-surface condition of complex geometrical boundaries can be satisfied naturally. This work is an extension of the grid method for the elastic wave propagation in heterogeneous isotropic media, and a quadrangular grid with low computational cost is also introduced.

关键词： numerical modeling anisotropy finite difference grid method

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SEISMIC RANDOM RESPONSE analYSIS OF HYSTERETIC SYSTEMS WITH PSEUDO EXCITATION METHOD

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Acta Mechanica Solida Sinica 2000年第3期13卷 246-253页

作者： Wang Jun Lin Jiahao Dalian Univ Technol State Key Lab Struct Anal Ind Equipment Dalian 116023 Peoples R China

The stationary random responses of nonlinear shear-typeMulti-degrees-of-Freedom (MDOF) hysteretic system are analyzed byusing the Pseudo Excitation Method (PEM) combined with the EquivalentLinerization Method (ELM). The solution of the equivalent linearsystem is obtained by iteratively solving complex algebraic equationsinstead of the Lyapunov equations. The efficiency of this method ismuch higher For practical engineering systems with manydegrees-of-freedom.

关键词： hysteretic system pseudo excitation method equivalent linearization

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NEW SOLUTION SYSTEM FOR CIRCULAR SECTOR PLATE BENDING AND ITS APPLICATION

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Acta Mechanica Solida Sinica 1999年第4期12卷 307-315页

作者： Yao, W Zhong, WX Su, B Dalian Univ Technol State Key Lab Struct Anal Ind Equipment Dalian 116023 Peoples R China

Instead of the biharmonic type equation, a set of new governing equations and solving method for circular sector plate bending is presented based on the analogy between plate bending and plane elasticity problems. So the Hamiltonian system can also be applied to plate bending problems by introducing bending moment functions. The new method presents the analytical solution for the circular sector plate. The results show that the new method is effective.

关键词： circular sector plate Hamiltonian system bending moment functions analogy

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Absorption,fluorescence and resonance Rayleigh scattering spectra of hydrophobic hydrogen bonding of eosin Y/Triton X-100 nanoparticles and their analytical applications

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Science China Chemistry 2010年第11期53卷 2363-2372页

作者： Ling Kong ZhongFang Liu XiaoLi Hu ShaoPu Liu Southwest Univ Sch Chem & Chem Engn Minist Educ Key Lab Luminescence & Real Time Anal Chongqing 400715 Peoples R China

In a weak acidic medium(pH 2.4-2.8),eosin Y molecules(H2L) could replace water molecules to associate with Triton X-100 to form hydrophobic hydrogen bonding *** complexes could further aggregate to form nanoparticles through the squeezing action of the water phase and Van der Waals force,resulting in changes in the absorption spectrum and fluorescence quenching of EY as well as the significant enhancement of resonance Rayleigh *** enables the sensitive determination of Triton X-100 using the fading spectrophotometry,fluorescence quenching method and RRS *** them,the RRS method shows the highest sensitivity with a detection limit of 20.6 ng mL-1 for Triton *** optimum experimental conditions and factors that affect the absorption,fluorescence and RRS spectra were *** effects of coexisting substances were investigated and the results showed good *** on these results,new spectrophotometric methods,fluorescence quenching method and RRS method for the determination of Triton X-100,were *** hydrogen bonding association of eosin Y with Triton X-100 and the formation of nanoparticles as well as their effects on related spectral characteristics were discussed utilizing infrared,transmission electron microscope technique and quantum chemical method.

关键词： eosin Y Triton X-100 resonance Rayleigh scattering fluorescence quenching absorption spectrum

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