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Chinese Journal of Polymer Science 2021年第6期39卷 779-788,I0009页

作者： Weichao Shi Key Laboratory of functional Polymer Materials of Ministry of Education Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

This work uses a block copolymer architecture[(A′B)nA2]m to unify the Scattering function and spinodal transition of typical AB-type block copolymers.The key roles of block number,junction points and asymmetry ratios of block length are(1)to determine the form factor of each block copolymer at the molecular scale;(2)to affect the entropy loss across the spinodal transition and may result in deflection of spinodal curves.The common features are validated in typical linear and nonlinear block copolymers,including AB diblock,asymmetric A′BA triblock,miktoarm stars of ABn,AnBn,(AB)n,(A′B)nA,A′BAm,and multi-graft combs of(BnA2)m and[(A′B)nA2]m.The explicit Scattering functions and form factors of various block copolymers can be directly applied in radiation experiments(i.***.neutron or X-ray scattering)to unravel the effect of molecular architecture in solution and microphase separation in disordered melt.The molecular model used in this study is also helpful to guide the chemical synthesis to explore more potentially interesting block copolymers.

关键词： Scattering function Form factor Spinodal transition Molecular structure Block copolymer

Research on the acoustic Scattering function and coherence properties from rough seafloor based on finite element model

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Chinese Physics B 2016年第12期25卷 85-91页

作者：雷波杨益新马远良陈东旭 School of Marine Science and Technology Northwestern Polytechnical University

Acoustic scattering from a rough sea bottom is recognized as a main source of reverberation. In this study, scattering properties from a layered bottom were exploited based on the finite element model. The scattering strength and loss from the layered rough seabed were investigated by ensembling the realizations of rough interface. They were found to be dependent on the thickness of sediment, and interference was significant in the case of thin sediment. Through verification of the finite element model, the scattering loss could be evaluated using the Eckart model with a proper sound speed in the thick sediment. The multiple scattering effect on the sound field was also exploited. It revealed that the effect depended strongly on the bottom type.

关键词： finite element rough seafloor Scattering function coherence

Scattering function OF POLYMER BLENDS

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Chinese Journal of Polymer Science 2004年第6期22卷 567-572页

作者：赵得禄 State Key Laboratory of Polymer Physics & Chemistry Center of Molecular Science Institute of ChemistryChinese Academy of Sciences Beijing 100080 China

For a system of flexible polymer molecules, the concepts of two concentrations, namely the segmental and the molecular concentrations, have been proposed in this paper. The former is equivalent to the volume fraction. The latter can be defined as the number of the gravity centers of macromolecules in a unit volume. The two concentrations should be correlated with each other by the conformational function of the polymer chain and should be discussed in different thermodynamic equations. On the basis of these concepts it has been proved that the Flory-Huggins entropy of mixing should be the result of the mixing 'ideal gases of the gravity centers of macromolecules'. The general correlation between the free energy of mixing and the Scattering function (structural factor) of polymer blends has been studied based on the general fluctuation theory. When the Flory-Huggins free energy of mixing is adopted, the de Gennes Scattering function of a polymer blend can be derived.

关键词： segmental concentration molecular concentration Scattering function

A Study on Ionospheric HF Channel with Bitemporal Response and Scattering function

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Wuhan University Journal of Natural Sciences 2000年第3期5卷 317-319页

作者： Chong Yan-wen Xie Shu-guo Zhao Zheng-yu Huang Tian-xi Yao Yong-gang College of Electronic Information Wuhan University Wuhan 430072 China

At first the bitemporal response method is introduced to solve the Scattering function of the ionospeeric channel. We can get the Scattering function, as a function, of the group path time delay and Doppler frequency. Thus Doppler effect resulting from the continuous movement of the ionosphere is analyzed to study the characteristics of the various ionospheric irregularities and diturbance. many possible problems and correction are researched lastly.

关键词： bitemporal response function Scattering function the Doppler effect the movement of the ionosphere

Automated Identification of Ordered Phases for Simulation Studies of Block Copolymers

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Chinese Journal of Polymer Science 2024年第5期42卷 683-692,I0011页

作者： Yu-Chen Zhang Wei-Ling Huang Yi-Xin Liu State Key Laboratory of Molecule Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

In unit cell simulations,identification of ordered phases in block copolymers(BCPs)is a tedious and time-consuming task,impeding the advancement of more streamlined and potentially automated research workflows.In this study,we propose a scattering-based automated identification strategy(SAIS)for characterization and identification of ordered phases of BCPs based on their computed scattering patterns.Our approach leverages the scattering theory of perfect crystals to efficiently compute the scattering patterns of periodic morphologies in a unit cell.In the first stage of the SAIS,phases are identified by comparing reflection conditions at a sequence of Miller indices.To confirm or refine the identification results of the first stage,the second stage of the SAIS introduces a tailored residual between the test phase and each of the known candidate phases.Furthermore,our strategy incorporates a variance-like criterion to distinguish background species,enabling its extension to multi-species BCP systems.It has been demonstrated that our strategy achieves exceptional accuracy and robustness while requiring minimal computational resources.Additionally,the approach allows for real-time expansion and improvement to the candidate phase library,facilitating the development of automated research workflows for designing specific ordered structures and discovering new ordered phases in BCPs.

关键词： Block copolymer Phase identification Scattering function

FRACTIONAL ANOMALOUS DIFFUSION CAUSED BY AN INSTANTANEOUS POINT SOURCE IN DISORDERED FRACTAL MEDIA

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FRACTIONAL ANOMALOUS DIFFUSION CAUSED BY AN INSTANTANEOUS PO...