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1.
Conjugated polymers are promising candidates for next‐generation low‐cost flexible electronics. Field‐effect transistors comprising conjugated polymers have witnessed significant improvements in device performance, notably the field‐effect mobility, in the last three decades. However, to truly make these materials commercially competitive, a better understanding of charge‐transport mechanisms in these structurally heterogeneous systems is needed for providing systematic guides for further improvements. This review assesses the key microstructural features of conjugated polymers across multiple length scales that can influence charge transport, with special attention given to the underlying polymer physics. The mechanistic understanding from collective experimental and theoretical studies point to the importance of interconnected ordered domains given the macromolecular nature of the polymeric semiconductors. Based on the criterion, optimization to improve charge transport can be broadly characterized by efforts to (a) promote intrachain transport, (b) establish intercrystallite connectivity, and (c) enhance interchain coupling. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1559–1571 相似文献
2.
The objective of this review is to organize literature data on the thermodynamic properties of salt‐containing polystyrene/poly(ethylene oxide) (PS/PEO) blends and polystyrene‐b‐poly(ethylene oxide) (SEO) diblock copolymers. These systems are of interest due to their potential to serve as electrolytes in all‐solid rechargeable lithium batteries. Mean‐field theories, developed for pure polymer blends and block copolymers, are used to describe phenomenon seen in salt‐containing systems. An effective Flory–Huggins interaction parameter, χeff , that increases linearly with salt concentration is used to describe the effect of salt addition for both blends and block copolymers. Segregation strength, χeffN , where N is the chain length of the homopolymers or block copolymers, is used to map phase behavior of salty systems as a function of composition. Domain spacing of salt‐containing block copolymers is normalized to account for the effect of copolymer composition using an expression obtained in the weak segregation limit. The phase behavior of salty blends, salty block copolymers, and domain spacings of the latter systems, are presented as a function of chain length, composition and salt concentration on universal plots. While the proposed framework has limitations, the universal plots should serve as a starting point for organizing data from other salt‐containing polymer mixtures. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1177–1187 相似文献
3.
Loo Wen-da 《应用数学和力学(英文版)》1981,2(1):79-102
In order to study the boundary conditions of integrated form(91a,d),firstlywe make use of trigonometrical series to express Nξη(0,η),Qξ*(0,η)of(97C,D).Suppose . 相似文献
4.
In the present paper a finite layer method is studied for the elastodynamics of transverse isotropic bodies. With this method,
semi-infinite soils can be considered as an transverse isotropic half-space, its material functions varying with depth. Dividing
the half-space into a series of layers in the direction of depth, the material functions in each layer are simulated by exponential
functions. Consequently, the fundamental equations to be solved can be simplified if the Fourier transform with repsect to
coordinates is used. We have obtained the relationship between the “layer forces” and “layer displacements”. This finite layer
method, in fact, can also be called a semi-analytical method. It possesses those advantages as the usual semi-analytical methods
do, and can be used to analyse the problem of the interaction between soils and structures.
This paper is based on a portion of the author's dissertation submitted in partial fulfillment of the requirements of degree
of Ph. D. at the Shanghai Institute of Appl. Math. & Mech., Shanghai. 相似文献
5.
In the present paper a finite layer method is studied for the elastodynamics of transverse isotropic bodies. With this method, semi-infinite soils can be considered as an transverse isotropic half-space, its material functions varying with depth. Dividing the half.space into a series of layers in the direction of depth the material fimetioms in each layer are simulated by exponential fumctions Consequently, the fundamental equations to be solved can be simplified if the fouricr transform with repsect to coordinates is used. We have obtained the relationship between the "layer forces" and "layer displacements". This finite layer method, in fact, can also be called a semi-analytical method. It possesses those advantages as the usual semi-analytical methods do, and can be used to analyse the problem of the interaction between soils and structures. 相似文献
6.
An integral equation formulation for buoyancy-driven convection problems is developed and illustrated. Buoyancy-driven convection in a bounded cylindrical geometry with a free surface is studied for a range of aspect ratios and Nusselt numbers. The critical Rayleigh number, the nature of the cellular motion, and the heat transfer enhancement are computed using linear theory. Green's functions are used to convert the linear problem into linear Fredholm integral equations. Theorems are proved which establish the properties of the eigenvalues and eigenfunctions of the linear integral operator which appears in these equations. 相似文献
7.
8.
Tandem mass spectrometry (MS/MS) of intact, noncovalently-bound protein-ligand complexes can yield structural information on the site of ligand binding. Fourier transform ion cyclotron resonance (FT-ICR) top-down MS of the 29 kDa carbonic anhydrase-zinc complex and adenylate kinase bound to adenosine triphosphate (ATP) with collisionally activated dissociation (CAD) and/or electron capture dissociation (ECD) generates product ions that retain the ligand and their identities are consistent with the solution phase structure. Increasing gas phase protein charging from electrospray ionization (ESI) by the addition of supercharging reagents, such as m-nitrobenzyl alcohol and sulfolane, to the protein analyte solution improves the capability of MS/MS to generate holo-product ions. Top-down proteomics for protein sequencing can be enhanced by increasing analyte charging. 相似文献
9.
Jamie YuLing Han Timothy Thatt Yang Tan Joachim Say Chye Loo 《Journal of nanoparticle research》2011,13(8):3441-3454
The aim of this study was to investigate the feasibility of the inverse micelles (IM) technique in producing protein-loaded
calcium phosphate nanoparticles (CaP NPs), and to compare this technique with the conventional co-precipitation (co-ppt) technique.
In this study, bovine serum albumin and lysozyme were used as model proteins. The results show that CaP NPs produced by IM
were shown to be spherical and homogenous in size of ~50 nm. Protein loading efficiency of the IM technique was shown to be
much higher than CaP NPs synthesized through co-ppt technique. X-ray photoelectron spectroscopy shows that proteins were not adsorbed onto the surface of IM-synthesized CaP NPs, which suggested
that the proteins were entrapped within the particle matrix. Release studies show that protein release was more rapid at lower
pH conditions (pH 5 and 6) than at physiological pH of 7.4. A burst release was observed for co-ppt CaP NPs, while a continuous
release of protein was observed for IM-produced CaP NPs. This study shows the superiority of the IM technique in preparing
pH responsive CaP NPs as nano-carriers. 相似文献
10.
Shirley H. Lomeli Sheng Yin Rachel R. Ogorzalek Loo Joseph A. Loo 《Journal of the American Society for Mass Spectrometry》2009,20(4):593-596
Increased multiple charging of native proteins and noncovalent protein complexes is observed in electrospray ionization (ESI)
mass spectra obtained from nondenaturing protein solutions containing up to 1% (vol/vol) m-nitrobenzyl alcohol (m-NBA). The increases in charge ranged from 8% for the 690 kDa α7β7β7α7 20S proteasome complex to 48% additional charge for the zinc-bound 29 kDa carbonic anhydrase-II protein. No dissociation
of the noncovalently bound ligands/subunits was observed upon the addition of m-NBA. It is not clear if the enhanced charging is related to altered surface tension as proposed in the “supercharging” model
of Iavarone and Williams (Iavarone, A. T.; Williams, E. R. J. Am. Chem. Soc.
2003, 125, 2319–2327). However, more highly charged noncovalent protein complexes have utility in relaxing slightly the mass-to-charge
(m/z) requirements of the mass spectrometer for detection and will be effective for enhancing the efficiency for tandem mass spectrometry
studies of protein complexes. 相似文献