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Colloidal organic carbon in Huanghe, Changjiang and Qiantang River

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Chinese Science Bulletin 1998年第11期43卷 915-917页

作者： WANG Jiangtao college of Chemistry and Chemical engineering, ocean university of qingdao, qingdao 266003, china Callege of Chemistry and Chemical engineering Ocean University of Qingdao Qingdao China

Cross-flow ultrafiltration techniques have been used to separate colloidal organic carbon (COC) from natural water, and COC in three water samples that were collected from Huanghe, Changjiang and Qiantang River was determined. On average, COC comprised about 68.6% of the total dissolved organic carbon. The abundance of COC suggested that COC could play important roles in input fluxes and biogeochemistry of organic carbon.

关键词： cross-flow ultrafiltration colloidal organic carbon.

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2:F film optically transparent electrode

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Science china Chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2 & NIU Shuyan1,2 1. college of Chemistry and Molecular engineering, qingdao university of Science and Technology, qingdao 266042, china 2. college of Chemistry and Chemical engineering, ocean university of china, qingdao 266003, china Correspondence should be addressed to Jiao Kui 1. college of Chemistry and Molecular engineering Qingdao University of Science and Technology 266042 Qingdao China 2. college of Chemistry and Chemical engineering Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2:F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

Boundary conditions for the bending of a piezoelectric beam

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2 & ZHAO BaoSheng3 1 college of Science, china Agricultural university, Beijing 100083, china 2.college of engineering, ocean university of china, qingdao 2.6071, china 3 School of Mechanical engineering, university of Science and Technology Liaoning, Anshan 114044, china 1. college of Science China Agricultural University Beijing 100083 China 2. college of engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay

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Acta oceanologica Sinica 2009年第2期28卷 121-126页

作者： CHEN Jie ZHEN Yu MI Tiezhu YU Zhigang college of Marine Life Science Ocean University of China Qingdao 266003 China college of Environmental Science and engineering Ocean University of China Qingdao 266100 China college of Chemistry and Chemical engineering Ocean University of China Qingdao 266100 China

Prorocentrum donghaiense is an important harmful algae bloom （HAB） causing creature in china＇s seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay （NPA-SH） was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x＋ 0.694 9, in which x is the cell number, and y is the optical density, with r2=0.953 5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense.

关键词： Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)

Mixed boundary conditions for piezoelectric plates

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2 &ZHAO BaoSheng 3 1college of Science,china Agricultural university,Beijing 100083,china 2college of engineering,ocean university of china,qingdao 2.6071,china 3 School of Mechanical engineering,university of Science and Technology of Liaoning,Anshan 114044,china college of Science China Agricultural University Beijing 100083 China college of engineering Ocean University of China Qingdao 266071 China School of Mechanical engineering University of Science and Technology of Liaoning Anshan 114044 China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Approximately optimal tracking control for discrete time-delay systems with disturbances

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Progress in Natural Science:Materials International 2008年第2期18卷 225-231页

作者： Gongyou Tang a,,Huiying Sun b,Haiping Pang c a college of Information Science and engineering,ocean university of china,qingdao 266100,china b college of Information and Electrical engineering,Shandong university of Science and Technology,qingdao 266510,china c college of Automation and Electronic engineering,qingdao university of Science and Technology,qingdao 266042,china college of Information Science and engineering Ocean University of China Qingdao 266100 China college of Information and Electrical engineering Shandong University of Science and Technology Qingdao 266510 China college of Automation and Electronic engineering Qingdao University of Science and Technology Qingdao 266042 China

Optimal tracking control (OTC) for discrete time-delay systems affected by persistent disturbances with quadratic performance index is considered. By introducing a sensitivity parameter,the original OTC problem is transformed into a series of two-point boundary value (TPBV) problems without time-advance or time-delay terms. The obtained OTC law consists of analytic feedforward and feedback terms and a compensation term which is the sum of an infinite series of adjoint vectors. The analytic feedforward and feedback terms can be found by solving a Riccati matrix equation and two Stein matrix equations. The compensation term can be obtained by using an iteration formula of the adjoint vectors. Observers are constructed to make the approximate OTC law physically realizable. A simulation example shows that the approximate approach is effective in tracking the reference input and robust with respect to exogenous persistent disturbances.

关键词： Discrete systems Time-delay systems Disturbances Optimal control Tracking control

Modeling of suspended sediment transport with wave-induced longshore current in Huanghe (Yellow) River Delta

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Acta oceanologica Sinica 2009年第3期28卷 65-74页

作者： LI Changliang LIANG Bingchen ZHANG Jing college of Petroleum engineering China University of Petroleum（East China） Qingdao266555 China engineering college Ocean University of China Qingdao 266100 China

A three-dimensional suspended sediment model （SED） developed by the present authors is coupled with the combinatorial model of COHERENS （Luyten et al., 1999）（the three-dimensional coupled hydrodynamical-ecological model for Regional and Shelf Seas） and SWAN （Holthuijsen et al., 2004）（the third generation wave model）. SWAN is regarded as a subroutine of COHERENS and gets time- and space-varying current velocity and surface elevation from COHERENS. COHERENS gets time- and space- varying wave relevant parameters provided by SWAN. Effects of wave on current are applied in bottom shear stress, wave-induced depth-dependent radiation stress and surface drag coefficient calculation. At the same time, the damping function of suspended sediment on turbulence is introduced into COHERENS. So the sediment model SED has feedback on circulation model COHERENS. The SED obtains current associated parameters from COHERENS. Then a coupled hydrodynamic-sediment model COHERENS-SED being able to account for interaction between wave and current is obtained. COHERENS-SED is adopted to simulate three-dimensional suspended sediment transport in the Huanghe River delta. In terms of simulation results, there is obvious difference between top and bottom layer of wave-induced longshore current. The values of time series of sediment concentration gotten by COHERENS-SED have, generally, an accepted agreement extent with measurement. Significant wave heights and wave periods obtained by COHERENS-SED show that wave simulation case with currentts effect can give better agreement extent with measurement than case without current＇s effect. In the meantime, suspended sediment concentration distributing rule obtained by COHERENS-SED is similar to former researches and measurement.

关键词： Huanghe River delta suspended sediment wave-induced longshore current COHERENS SWAN COHERENS-SED

A maximum entropy distribution for wave heights of non-linear sea waves

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Progress in Natural Science:Materials International 2007年第11期17卷 1318-1326页

作者： Zhou Liangming1, Xu Delun1, Wang Aifang1, Chen Zhengshou2 and Yan Xiuhua1(1. Physical oceanography Laboratory, ocean university of china, qingdao 266100,china 2.engineering college, ocean university of china, qingdao 2.6071, china) Physical oceanography Laboratory Ocean University of China Qingdao 266100China 2.engineering college Ocean University of China Qingdao 266071 China

Based on the maximum entropy principle,a probability density function (PDF) for the zero-crossing wave height (H) of random waves is derived as the simple form fn(H)=αHγe-βHn (n is a selectable positive integer) through solving a variational problem subject to some quite general constraints. This PDF maximizes the information entropy of H, and its parameters α, γ and β are expressed explicitly in terms of the distribution moments m, m=1,2,…,n, so it is well competent for describing the distribution of H of nonlinear sea waves with large uncertainty, and its parameters can be simply determined from available data. Comparisons between the PDF with n=3 and n=4 and the observed distributions of H from wave records measured in the East china Sea and in a wind-wave tunnel show fairly satisfying agreements.

关键词： sea waves the maximum entropy principle probability density function

Bubble size distribution in surface wave breaking entraining process

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Science china Earth Sciences 2007年第11期50卷 1754-1760页

作者： HAN Lei1,2 & YUAN YeLi2 1 Department of ocean Environment, ocean university of china, qingdao 266003, china 2 The First Institute of oceanography, State ocean Administration, qingdao 266061, china 1. Department of ocean Environment Ocean University of China Qingdao 266003 China 2. The First Institute of oceanography State Ocean Administration Qingdao 266061 China

From the similarity theorem, an expression of bubble population is derived as a function of the air en-trainment rate, the turbulent kinetic energy (TKE) spectrum density and the surface tension. The bubble size spectrum that we obtain has a dependence of a?2.5+nd on the bubble radius, in which nd is positive and dependent on the form of TKE spectrum within the viscous dissipation range. To relate the bubble population with wave parameters, an expression about the air entrainment rate is deduced by intro-ducing two statistical relations to wave breaking. The bubble population vertical distribution is also derived, based on two assumptions from two typical observation results.

关键词： wave breaking,bubble cloud,bubble size spectrum