The complex variable reproducing kernel particle method for two-dimensional elastodynamics

On the basis of the reproducing kernel particle method （RKPM）, a new meshless method, which is called the complex variable reproducing kernel particle method （CVRKPM）, for two-dimensional elastodynamics is presented in this paper. The advantages of the CVRKPM are that the correction function of a two-dimensional problem is formed with one-dimensional basis function when the shape function is obtained. The Galerkin weak form is employed to obtain the discretised system equations, and implicit time integration method, which is the Newmark method, is used for time history analysis. And the penalty method is employed to apply the essential boundary conditions. Then the corresponding formulae of the CVRKPM for two-dimensional elastodynamics are obtained. Three numerical examples of two-dimensional elastodynamics are presented, and the CVRKPM results are compared with the ones of the RKPM and analytical solutions. It is evident that the numerical results of the CVRKPM are in excellent agreement with the analytical solution, and that the CVRKPM has greater precision than the RKPM.

Combining the complex variable reproducing kernel particle method and the finite element method for solving transient heat conduction problems

In this paper, the complex variable reproducing kernel particle （CVRKP） method and the finite element （FE） method are combined as the CVRKP-FE method to solve transient heat conduction problems. The CVRKP-FE method not only conveniently imposes the essential boundary conditions, but also exploits the advantages of the individual methods while avoiding their disadvantages, then the computational efficiency is higher. A hybrid approximation function is applied to combine the CVRKP method with the FE method, and the traditional difference method for two-point boundary value problems is selected as the time discretization scheme. The corresponding formulations of the CVRKP-FE method are presented in detail. Several selected numerical examples of the transient heat conduction problems are presented to illustrate the performance of the CVRKP-FE method.

Hydrolysis Activities of the Particle of Agarose-Ce^(4+) Complex for Compounds Containing Phosphodiester or Peptide Bonds

Hydrolysis activities of PACC (particle of agarose-Ce4+ complex, newly made through double emulsification) forcompounds containing phosphodiester or peptide bonds were studied. The results showed that PACC could hydrolyzeorganophosphorous pesticides not only in water but also in vegetable juice or tea extract. Hydrolysis rates of methamidophos,omethoate and chlorpyrifos in water are 32.39%, 27.12% and 46.62% respectively, those of chlorpyrifos and methami-dophos in mung sprout juice 38.28% and 35.45% respectively, and that of chlorpyrifos in tea extract 59.76%. Hydrolysisrates of BSA (bovine serum albumin) in water and protein in tea extract by PACC increase by 54.30% and 86.46% respec-tively as compared with the control.

Analysis of variable coefficient advection-diffusion problems via complex variable reproducing kernel particle method

The complex variable reproducing kernel particle method （CVRKPM） of solving two-dimensional variable coefficient advection-diffusion problems is presented in this paper. The advantage of the CVRKPM is that the shape function of a two-dimensional problem is formed with a one-dimensional basis function. The Galerkin weak form is employed to obtain the discretized system equation, and the penalty method is used to apply the essential boundary conditions. Then the corresponding formulae of the CVRKPM for two-dimensional variable coefficient advection-diffusion problems are obtained. Two numerical examples are given to show that the method in this paper has greater accuracy and computational efficiency than the conventional meshless method such as reproducing the kernel particle method （RKPM） and the element- free Galerkin （EFG） method.

A novel, simple and sensitive resonance scattering spectral method for the determination of chlorite in water by means of rhodamine B

A new resonance scattering method was proposed for the determination of chlorite, basing on the resonance scattering effect of rhodamine dye. In HCl-sodium acetate buffer solution, chlorite oxidizes 1- into 12 and the reaction of 12 and excess 1- results in If. It is respectively combined with rhodaminc dyes, including rhodamine B （RhB）, butyl rhodamine B （b-RhB）, rhodamine G （RhG） and rhodamine S （RhS）, to form association complex particles, which exhibit stronger resonance scattering （RS） effect at 400 nm. The chlorite concentration of ClO2 in the range of 0.00726-0.218 μg/ml, 0.0102-0.292 μg/ml, 0.00726-0.145 μg/ml and 0.0290- 0.174 μg/ml is respectively linear to the RS intensity of association complex particle systems at 400 nm for the RhB, b-RhB, RhG and RhS. The detection limits of the four systems were respectively 0.00436, 0.00652, 0.00580 and 0.01450μg/ml ClO2^-. In the four systems, the RhB system possesses good stability and high sensitivity. It has been applied to the analysis of chlorite in wastewater with satisfactory results.

A New and Sensitive Catalytic Resonance Scattering Spectral Assay for the Detection of Laccase Activity Using H2O2-1-TDMAC System

In pH 3.8 acetic acid-sodium acetate （HAC-NaAC） buffer solution, laccase exhibited a strong catalytic effect on the H2O2 oxidation of I- to form I2, and I2 combined with excess I- to form I3- that reacted with cationic surfactants of tetradecyl dimethylbenzyl ammonium chloride （TDMAC） to produce the （TDMAC-I3）n association complex particles, which exhibited a strong resonance scattering （RS） peak at 468 nm. Under the chosen conditions, as the concentration of laccase activity increased, the RS intensity at 468 nm （1468 nm） increased linearly. The increased RS intensity A1468 nm was linear to laccase activity in the range of 0.08-0.96 U/mL, with a regression equation of △1468 nm =88.8 U-1.9, and a detection limit of 0.02 U/mL laccase. This proposed method was applied to detect laccase activity in waste water, with satisfactory results.