EDTA interfacial chelation Ca^(2+) incorporates superhydrophobic coating for scaling inhibition of CaCO_(3) in petroleum industry

In this paper,the superhydrophobic poly(vinylidene fuoride)/fuorinated ethylene propylene/SiO_(2)/CNTs-EDTA(PFSCEDTA)composite coating was successfully fabricated and applied for anti-scaling performance.The deposition of CaCO_(3) on the surface of the superhydrophobic PFSC-EDTA composite coating reached 0.0444 mg/cm^(2) for 192-h immersion into the supersaturated CaCO_(3) solution,which was only 11.4%that of the superhydrophobic PFSC composite coating.At the interface between the CaCO_(3) solution and the PFSC-EDTA coating,the Ca^(2+)could be frstly chelated by EDTA that was beneft for improving the anti-scaling performance of the superhydrophobic PFSC-EDTA composite coating.In another hand,the addition of EDTA to the CNTs played an important role in fabricating the SiO_(2)-centric and CNTs-EDTA-surrounded multilevel micro-nanostructure in the superhydrophobic PFSC-EDTA composite coating,in favor of maintaining the air flm under the water and the stability of the superhydrophobic surface.The research supplies a new way of improving antiscaling performance of superhydrophobic coating by incorporating the organic chelating agent at the interface and changing the traditional way of scale prevention.

Effects of rice or wheat residue retention on the quality of milled japonica rice in a rice–wheat rotation system in China

In rice–wheat rotation systems, crop straw is usually retained in the field at land preparation in every, or every other, season. We conducted a 3-year-6-season experiment in the middle–lower Yangtze River Valley to compare the grain qualities of rice under straw retained after single or double seasons per year. Four treatments were designed as: both wheat and rice straw retained(WR), only rice straw retained(R), only wheat straw retained(W), and no straw retained(CK). The varieties were Yangmai 16 wheat and Wuyunjing 23 japonica rice. The results showed contrasting effects of W and R on rice quality. Amylopectin content, peak viscosity, cool viscosity, and breakdown viscosity of rice grain were significantly increased in W compared to the CK, whereas gelatinization temperature,setback viscosity, and protein content significantly decreased. In addition, the effect of WR on rice grain quality was similar to that of W, although soil fertility was enhanced in WR due to straw being retained in two cycles. The differences in protein and starch contents among the treatments might result from soil nitrogen supply. These results indicate that wheat straw retained in the field is more important for high rice quality than rice straw return, and straw from both seasons is recommended for positive effects on soil fertility.

The Analysis of Global Input-to-state Stability for Piecewise Affine Systems with Time-delay

In this paper, global input-to-state stability （ISS） for discrete-time piecewise affine systems with time-delay are considered Piecewise quadratic ISS-Lyapunov functions are adopted. Both Lyapunov-Razumikhiu and Lyapunov-Krasovskii methods are used The theorems of Lyapunov-Razumikhin type and Lyapunov-Krasovskii type for piecewise affine systems with time-delay are shown respectively.

Periodic, Quasiperiodic and Chaotic Discrete Breathers in a Parametrical Driven Two-Dimensional Discrete Klein-Gordon Lattice

We study a two-dimensional lattice of anharmonic oscillators with only quartic nearest-neighbor interactions, in which discrete breathers can be explicitly constructed by an exact separation of their time and space dependence. DBs can stably exist in the two-dimensional Klein-Gordon lattice with hard on-site potential. When a parametric driving term is introduced in the factor multiplying the harmonic part of the on-site potential of the system, we can obtain the stable quasiperiodic discrete breathers and chaotic discrete breathers by changing the amplitude of the driver.

Surface Acoustic Wave Propagation in Relaxor-Based Ferroelectric Single Crystals 0.93Pb(Zn_(1/3)Nb_(2/3))O_(3)-0.07PbTiO3 Poled along [011]c

Surface acoustic wave (SAW) propagation in relaxor-based ferroelectric single crystals 0.93Pb(Zn_(1/3)Nb_(2/3))O_(3)- 0.07Pb TiO_(3) (PZN- 7%PT ) poled along [011]c has been analyzed theoretically.The results show that PZN- 7% PT single crystals have excellent SAW properties,such as low phase velocities,very high electromechanical coupling coefficients and small power flow angles.It is also found that the SAW properties strongly depend on the propagation direction and the characteristic curves of SAW phase velocity,and the electromechanical coupling coefficients are symmetric with respect to θ =90°.Considering all related factors,the X-cut PZN-7%oPT single crystal has the best performance.Based on our results,the X-cut PZN-7%PT single crystals poled along [011]c are an excellent candidate for ultra-wide bandwidth low-frequency SAW devices.

Numerical Calculation of SAW Propagation Properties at the x-Cut of Ferroelectric PMN-33%PT Single Crystals

Surface acoustic wave （SAW） properties at the x-cut of relaxor-based 0.67Pb（Mg1/3Nb2/3）O3-0.33PbTiO3 （PMN- 33%PT） ferroelectric single crystals are analyzed theoretically when poled along the [001]c cubic direction. It can be found that PMN-33%PT single crystal is a kind of material with a low phase velocity and high electromechanical coupling coefficient, and the single crystal possesses some cuts with zero power flow angle. The results are based on the material parameters at room temperature. The conclusions provide device designers with a few ideal cuts of PMN-33%PT single crystals. Moreover, choosing an optimal cut will dramatically improve the performance of SAW devices, and corresponding results for crystal systems working at other temperatures could also be figured out by employing the method.

Periodic, Quasiperiodic and Chaotic q-Breathers in a Fermi-Pasta-Ulam Lattice

我们由数字方法在一个 Fermi-Pasta-Ulam 格子学习单个 q 呼吸(SQB ) 的特征，并且获得 SQB 的稳定性相关到联合经常的 K 和非线性的参数。不管是否 K 或增加，周期的 SQB 能被转变成 quasiperiodic SQB 或混乱 SQB。我们也获得刺激的条件周期， quasiperiodic 和混乱 SQB。

Morphological Characteristics and Environmental Implications of Phytoliths in Topsoils from Different Vegetation Zones on Northern Slope of Changbai Mountains,China

The Changbai Mountains,located in the temperate monsoon climate zone of East Asia,is an ideal loca-tion for the research on timberline response to global changes.In this study,the topsoils were collected from different vertical vegetation zones on the northern slope of the Changbai Mountains,Northeast China in August 2009,and phytoliths in the soil samples were extracted by using wet oxidation method and identified with Motic 2.0 microscope in laboratory.The results show that phytoliths are abundant in the topsoils of the study area.The herbal phytoliths are primarily composed of elongated,tooth-shaped,point-shaped and hat-shaped phytoliths,as well as a small amount of fan-shaped and square-shaped ones.The elongated,tooth-shaped,point-shaped and hat-shaped phytoliths are representative of cold climate,while fan-shaped and square-shaped ones are representative of warm and humid climate.In the conifer broadleaved mixed forest zone,coniferous forest zone and broadleaf forest zone,there are close correlations between vegetation and woody phytoliths in the topsoils,indicating that the woody plants of a region can be reconstructed from the woody phytolith assemblages in the topsoils.Meanwhile,the topsoil phytolith assemblages can also be used to reconstruct the understory herbs effectively.The phytolith assemblages in the topsoils of the forest community and herbal community differ significantly,which can help indicate the historical location of the timberline.

Two-Dimensional Breather Lattice Solutions and Compact-Like Discrete Breathers and Their Stability in Discrete Two-Dimensional Monatomic β-FPU Lattice

我们把我们的注意限制为分离二维的单原子的 β-FPU 格子。我们由使用试一试的方法寻找二维的 breather 格子答案和二维的像协议的分离呼吸 ers 并且由使用 Aubry 的线性地稳定的理论分析他们的稳定性。我们在分离二维的单原子的 β-FPU 格子获得存在的条件和二维的 breather 格子答案和二维的像协议的分离呼吸 ers 的稳定性。

Waveguide Invariant and Passive Ranging Using Double Element

The sea-trial results indicate that the stable interference structure can be observed in low-frequency continuous spectra sound field.And the equation of the interference striation have been derived in light of the comcept of waveguide invariant, indicating that the striations are a family of quasi hyperbolas. The heading angle φ, waveguide invariant β and r0/v(r0 is the range of the closest point of approach and v is the navigating velocity of target) are estimated by using Hough transform for the image processing of the LOFARgram and bearing-time records. Four passive ranging algorithms based on double element or double array model are proposed. The simulation research shows that the first positioning algorithm should be adopted when the target heading angle is less than 10°; otherwise, the latter three algorithms are used to range, and the larger the heading angle is, the higher the positioning accuracy is. The relative ranging errors of the four methods are less than 10% under the simulation conditions used in this paper.

The 3D solitons and vortices in 3D discrete monatomic lattices with cubic and quartic nonlinearity

By virtue of the method of multiple-scale and the quasi-discreteness approach, we have discussed the nonlinear vibration equation of a 3D discrete monatomic lattice with its nearest-neighbours interaction. The 3D simple cubic lattices have the same localized modes as a 1D discrete monatomic chain with cubic and quartic nonlinearity. The nonlinear vibration in the 3D simple cubic lattice has 3D distorted solitons and 3D envelop solitons in the direction of kx = ky = kz = k and k = ±π/6α0 in the Brillouin zone, as well as has 3D vortices in the direction of kx = ky = kz = k and k = ±π/α0 in the Brillouin zone.

Localized self-trapping in two-dimensional molecular lattice with interaction between Wannier-Mott excitons and phonon lattice

We investigate the interactions of lattice pbonons with Wannier-Mott exciton, the exciton that has a large radius in two-dimensional molecular lattice, by the method of continuum limit approximation, and obtain that the self-trapping can also appear in two-dimensional molecular lattice with a harmonic and nonlinear potential. The exciton effect on molecular lattice does not distort the molecular lattice but only makes it localized and the localization can also react, again through phonon coupling, to trap the energy and prevents its dispersion.

Localized self-trapping in the two-dimensional discrete molecular lattice with the interaction between Frenkel excitons and phonons

We investigate the interactions of lattice phonons with Frenkel exciton, which has a small radius in a twodimensional discrete molecular lattice, by the virtue of the quasi-discreteness approximation and the method of multiplescale, and obtain that the self-trapping can also appear in the two-dimensional discrete molecular lattice with harmonic and nonlinear potential. The excitons＇ effect on the molecular lattice does not distort it but only causes it to localize which enables it to react again through phonon coupling to trap the energy and prevent its dispersion.

Periodic,quasiperiodic and chaotic discrete breathers in a parametrical driven two-dimensional discrete diatomic Klein-Gordon lattice

We study a two-dimensional （2D） diatomic lattice of anhaxmonic oscillators with only quartic nearest-neighbor interactions, in which discrete breathers （DBs） can be explicitly constructed by an exact separation of their time and space dependence. DBs can stably exist in the 2D discrete diatomic Klein-Gordon lattice with hard and soft on-site potentials. When a parametric driving term is introduced in the factor multiplying the harmonic part of the on-site potential of the system, we can obtain the stable quasiperiodic discrete breathers （QDBs） and chaotic discrete breathers （CDBs） by changing the amplitude of the driver. But the DBs and QDBs with symmetric and anti-symmetric profiles that are centered at a heavy atom are more stable than at a light atom, because the frequencies of the DBs and QDBs centered at a heavy atom are lower than those centered at a light atom.

Surface lurking and interfacial ion release strategy for fabricating a superhydrophobic coating with scaling inhibition

The design and manufacture of anti-scaling surface is a prospective way to prevent scaling in oil field.In this work,a novel superhydrophobic Cu^(2+)-loaded and DTPMPA-modified anodized copper oxide(S-Cu^(2+)/D-ACO)coating was fabricated by modification of 1H,1H,2H,2H-perfluorodecyltriethoxysilane.The valid storing of scale inhibitors at the coating surface and the interfacial release of Cu^(2+)ions contribute to enhancing the anti-scaling of the S-Cu^(2+)/D-ACO coating.The water contact angle of the S-Cu^(2+)/D-ACO coating is 163.03°and exhibits superhydrophobicity,which makes it difficult for CaCO_(3)to deposit at the surface of the coating.DTPMPA will steadily lurk into the inner space,and Cu^(2+)will be loaded at the interface in the form of the DTPMPA:Cu^(2+)chelate.During the deposition of CaCO_(3),the dynamic release of DTPMPA can be realized by transferring DTPMPA:Cu^(2+)to DTPMPA:Ca^(2+).Interestingly,the released Cu^(2+)hinders the active growth of CaCO_(3).After 48 h of scaling,the mass of CaCO_(3)scale at the S-Cu^(2+)/D-ACO coating surface is only 44.1%that of the anodized copper oxide coating.The excellent anti-scaling performance of the S-Cu^(2+)/D-ACO coating is determined by the synergistic effect of the DTPMPA lurking and dynamic release,as well as the Cu^(2+)inhibition at the interface of superhydrophobic coating and against CaCO_(3)deposition.This research provides a new exploration for designing and fabricating anti-scaling superhydrophobic surface for oil field development.

Existence and Stability of Compact-Like Discrete Breather in Discrete One-Dimensional Monatomic Chains

在分离的一个维的单原子的链的像协议的分离呼吸 ers 被讨论调查一概括了分离一个维的单原子的模型。像协议的分离 breather 是，这被证明在软 phi (4 ) 存在不仅潜在而且在难 phi (4 ) ，潜力被联合链不与联合参数 K-4 有关的参数 K-4 决定。像协议的分离 breather 仔细，到联合，参数 K-4 和边界格子调节的相互关联的稳定性。

On Some Classes of New Solutions of Continuous β-FPU Chain

A continuous β-Fermi-Pasta-Ulam （FPU） chain is investigated by using the knowledge of elliptic equation and Jacobian elliptic functions. We obtain the new solutions, two-kink soliton solution, breather solution and breather lattice solution, of the continuous β-FPU chain, besides the kink-soliton solution and chaos solution.

Existences and stabilities of bright and dark breathers in a general one-dimensional discrete monatomic Chain

A general one-dimensional discrete monatomic model is investigated by using the multiple-method. It is proven that the discrete bright breathers （DBBs） and discrete dark breathers （DDBs） exist in this model at the anti-continuous limit, and then the concrete models of the DBBs and DDBs are also presented by the multiple-scale approach （MSA） and the quasi-discreteness approach （QDA）. When the results are applied to some particular models, the same conclusions as those presented in corresponding references are achieved. In addition, we use the method of the linearization analysis to investigate this system without the high order terms of ε. It is found that the DBBs and DDBs are linearly stable only when coupling parameter χ is small, of which the limited value is obtained by using an analytical method.

Synthesis of Octylmethoxycinamate-silica Core-shell Nanoparticles with Self-templating Method

t A self-templating method was employed to synthesize core-shell nanoparticles with octylmethoxycinamate（OMC）, a well-known organic UV absorber, as core and nanosilica particles as shell. The characteristic of this method is that the whole process requires neither surface treatment for nanosilica particles nor additional surfactant or stabilizer, and all the reactions could be finished in one-pot, which exempts removing template and reduces reaction steps compared to the conventional process. The morphology, structure, particle size distribution, chemical composition and optical property of OMC-SiO2 nanoparticles were characterized by scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, dynamic light scattering（DLS）, FTIR spectrometry and UV absorption spectrometry, respectively. Experiment results indicate that the resulting OMC-SiO2 nanoparticles were perfectly spherical with smooth particle surfaces, and had clear core-shell structures. The particle size could be tuned by altering reaction conditions. In addition, the mechanism of the self-templating method for forming core-shell nanoparticles was discussed.

Size Effects of the Properties in a Ferroelectric Bilayer Film with Surface Transition Layers

Using the transverse Ising model theory,a ferroelectric bilayer film,considering the surface transition layer within each constituent slab and an interracial coupling between two slabs,is investigated in the framework of the mean-field approximation.We discuss in detail the thickness effects of the spontaneous polarization and dielectric susceptibility ofa ferroelectric bilayer film under two conditions of interracial coupling:ferroelectric and antiferroelectric coupling.The results show some unexpected phenomena for a small thickness of a ferroelectric bilayer film.