Effects of solution conditions on the physicochemical properties of stratification components of extracellular polymeric substances in anaerobic digested sludge

The composition and effects of solution conditions on the physicochemical properties of the stratification components of extracellular polymeric substances （EPS） in anaerobic digested sludge were determined. The total EPS in anaerobic digested sludge were extracted by the cation exchange resin method. Another EPS extraction method, the ceutrifugation and sonication technique was employed to stratify the EPS into three fractions： slime, loosely bound （LB）-EPS, and tightly bound （TB）-EPS from the outside to the inside of the anaerobic digested sludge. Proteins and polysaccharides were dispersed uniformly across the different EPS fractions, and humic-like substances were mainly partitioned in the slime, with TB-EPS second. Protein was the major constituent of the LB-EPS and TB-EPS, and the corresponding ratios ranged from 54.0% to 65.6%. The hydrophobic part in the EPS chemical components was primarily comprised of protein and DNA, while the hydrophilic part was mainly composed of polysaccharide. In the slime, the hydrophobic values of several EPS chemical components （protein, polysaccharide, humic-like substances and DNA） were all below 50%. The protein/polysaccharide ratio had a significant influence on the Zeta potentials and isoelectric point values of the EPS： the greater the protein/polysaccharide ratio of the EPS was, the greater the Zeta potential and the higher the isoelectric point value were. All Zeta potentials of the EPS showed a decreasing trend with increasing pH. The corresponding isoelectric point values （pH） were 2.8 for total EPS, 2.2 for slime, 2.7 for LB-EPS, and 2.6 for TB-EPS. As the ionic strength increased, the Zeta potentials sharply increased and then gradually became constant without charge reversal. In addition, as the temperature increased （〈 40℃）, the apparent viscosity of the EPS decreased monotonically and then gradually became stable between 40 and 60℃.

A PRIORI ESTIMATES TO THE MAXIMUM MODULUS OF GENERALIZED SOLUTIONS OF A CLASS OF QUASILINEAR ELLIPTIC EQUATIONS WITH ANISOTROPIC GROWTH CONDITIONS

In this paper we give a priori estimates for the maximum modulus of generalizedsolulions of the quasilinear elliplic equations irith anisotropic growth condition.

EXISTENCE OF NONTRIVIAL SOLUTION OF QUASILINEAR ELLIPTIC EIGENVALUE PROBLEM ON R^n WITH NATURAL GROWTH CONDITIONS

In this paper, we get the existence result of the nontrivial weak solution (λ, u) of the following eigenvalue problem with natural growth conditions.

SOLUTION TO A PARAMETRIC EQUATION WITH GENERALIZED BOUNDARY CONDITION IN TRANSPORT THEORY

This paper deals with the solution of a parametric equation with generalized boundary condiiton in transport theory. It gives the distribution of parameter (so called delta-eigenvalue [1]) with which the equation has non-zero solution. A necessary and sufficient condition for the existence of; he control critical eigenvalue delta0 is established.

Compatibility of Soybean Protein and Poly (vinyl alcohol)

Bicomponent fibers were wet-spun from soybean protein and poly (vinyl alcohol). The fiber was brittle and showed a high frequency of breakage upon drawing and the bad compatibility between soybean protein and poly (vinyl alcohol) was thought to be the causes for the poor drawability. Our effort was then to study the soybean protein and poly (vinyl alcohol) solution, with the aim of trying to improve the components’ compatibility and to determine the proper solution condition for dissolving them. The effects of alkali, sodium sulfite and urea on the compatibility of the solution were examined.

The Existence of a Weak Solution of Inhomogeneous Quasilinear Elliptic Equation with Critical Growth Conditions

In this paper, we get the existence of a weak solution of the following inhomogeneous quasilinear elliptic equation with critical growth conditions: where N≥2, f（x,u）～|u|m-1eb|u|γat +∞, with γ=N/N-1, m≥1, b】0.

Approximate derivative-dependent functional variable separation for quasi-linear diffusion equations with a weak source

By using the approximate derivative-dependent functional variable separation approach, we study the quasi-linear diffusion equations with a weak source ut = （A（u）Ux）x ＋ eB（u, Ux）. A complete classification of these perturbed equations which admit approximate derivative-dependent functional separable solutions is listed. As a consequence, some approxi- mate solutions to the resulting perturbed equations are constructed via examples.

Numerical study of homogeneous–heterogeneous reactions on stagnation point flow of ferrofluid with non-linear slip condition

This study deals with the stagnation point flow of ferrofluid over a flat plate with non-linear slip boundary condition in the presence of homogeneous-heterogeneous reactions.Three kinds of ferroparticles,namely,magnetite(Fe_3O_4),cobalt ferrite(CoFe_2O_4) and manganese zinc ferrite(Mn-ZnFe_2O_4) are taken into account with water and kerosene as conventional base fluids.The developed model of homogeneous-heterogeneous reactions in boundary layer flow with equal and unequal diffusivities for reactant and autocatalysis is considered.The governing partial differential equations are converted into system of non-linear ordinary differential equations by mean of similarity transformations.These ordinary differential equations are integrated numerically using shooting method.The effects of pertinent parameters on velocity and concentration profiles are presented graphically and discussed.We found that in the presence of Fe_3O_4-kerosene and CoFe_2O_4-kerosene,velocity profiles increase for large values of α and β whereas there is a decrement in concentration profiles with increasing values of if and K_s.Furthermore,the comparison between non-magnetic(A1_2O_3) and magnetic Fe_3O_4 nanoparticles is given in tabular form.

Existence of weak solutions for non-stationary flows of fluids with shear thinning dependent viscosities under slip boundary conditions in half space

This paper treats the system of motion for an incompressible non-Newtonian fluids of the stress tensor described by p-potential function subject to slip boundary conditions in R_+~3. Making use of the Oseentype approximation to this model and the L~∞-truncation method, one can establish the existence theorem of weak solutions for p-potential flow with p ∈(8/5, 2] provided that large initial are regular enough.

NECESSARY AND SUFFICIENT CONDITIONS FOR THE EXISTENCE OF PERIODIC SOLUTIONS OF RICCATI'S EQUATION WITH PERIODIC COEFFICIENTS

In this paper, the concept of generalized ω-periodic solution is given for Riccati's equationy'=a(t)y^2+b(t)y+c(t)with perriodic coefficients, the relation between generalized ω-periodicsolutions and the characteristic numbers of system x'_1=c(t)x_2, x'_2=-a(t)x_1-b(t)x_2 is indicated, andseveral necessary and sufficient conditions are given using the coefficients. Moreover, in the case of a(t)without zero, the relation between the number of continuous ω-periodic solutions of y'=a(t)y^2+b(t)y+c(t)+δand the parameter δ is given; thus the problem on the existence of continuous ω-periodic.solutions is basically solved.

THE NECESSARY AND SUFFICIENT CONDITIONS FOR THE EXISTENCE 0F PERIODIC SOLUTIONS OF A TYPE OF NEUTRAL FUNCTIONAL DIFFERENTIAL EQUATIONS

In this paper, using Fourier series, we study the problem of the existence of periodic solutionsof a type of periodic neutral differential difference system. Some necessary and sufficient conditionsfor the existence of periodic solutions of a type of neutral functional equation system are obtained,and at the same time, we present a method with formula shows how to find the periodicsolutions.

Radiation efects on MHD stagnation point flow of nano fluid towards a stretching surface with convective boundary condition

The aim of the present paper is to study the numerical solutions of the steady MHD two dimensional stagnation point flow of an incompressible nano fluid towards a stretching cylinder.The effects of radiation and convective boundary condition are also taken into account.The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis.The resulting nonlinear momentum,energy and nano particle equations are simplifed using similarity transformations.Numerical solutions have been obtained for the velocity,temperature and nanoparticle fraction profles.The influence of physical parameters on the velocity,temperature,nanoparticle fraction,rates of heat transfer and nanoparticle fraction are shown graphically.

BOUNDARY VXLUE PROBLEMS FOR SYSTEMS OF NONLINEAR SECOND ORDER DIFFERENTIAL DFFERENCE EQUATIONS

The author studies the boundary value problems for systems of nonlinear second order differential dmerence equstions and adopts a new-type Nagumo conditinn, in which the controlfunction is a vector-Valued function of several variables and which can guarsntee simultaneously and easily finding a priori bounds of eaCh component of the deriVatives of the solutions.Under this new-type Nagumo condition the existence results of solution are proved by meansof differential inopality technique.