Two plant proteins, soyprotein and wheat gluten, and chicken feathers used to size cotton substrates provided sizing performance similar to starch and were also easily degraded in activated sludge. Sizing is an essential process to impart protection to warp yarns and increase weaving efficiency. Cotton yarns have traditionally been sized with starch, modified starch derivatives, CMC, poly vinyl alcohol (PVA), or a combination thereof along with quite a few other fiber binding ingredients. Although starch and starch derivatives are extensively used for sizing, there can be several limitations including less-than-satisfactory sizing performance and difficulties in desizing starch based size. Plant proteins such as wheat gluten, soyproteins and poultry feathers are available in large quantities at low cost and have limited industrial applications. However, these proteins are known to have excellent film-forming properties, a primary requirement for a warp size, and have also been used as adhesives. Using proteins as warp sizing agents on cotton yarns potentially could provide acceptable sizing performance and be cost-effective, as well. In this research, soyproteins, wheat gluten, and chicken feathers were studied for exploring their feasibility for sizing, desizing, biodegradability, and ability to replace starch and PVA for sizing cotton yarns. It was found that all three proteins provided similar cohesion to fibers and abrasion resistance compared to starch. Protein sizes had significantly high BOD5/COD ratio compared to PVA, suggesting that the proteins are easily degradable in textile effluent treatment plants. 相似文献
The feasibility of realizing a photonic Floquet topological insulator (PFTI) in an atomic ensemble is demonstrated. The interference of three coupling fields will split energy levels periodically, to form a periodic refractive index structure with honeycomb profile that can be adjusted by different frequency detunings and intensities of the coupling fields. This in turn will affect the appearance of Dirac cones in momentum space. When the honeycomb lattice sites are helically ordered along the propagation direction, gaps open at Dirac points, and one obtains a PFTI in an atomic vapor. An obliquely incident beam will be able to move along the zigzag edge of the lattice without scattering energy into the PFTI, due to the confinement of edge states. The appearance of Dirac cones and the formation of a photonic Floquet topological insulator can be shut down by the third‐order nonlinear susceptibility and opened up by the fifth‐order one.
A two-dimensional cluster model in which the morphology of clusters depends on power-law magnetic interactions that decay with distance r as a r−α law is introduced. The growth algorithm is a generalization of diffusion-limited aggregation (DLA) model. The particles with spin degree diffuse on a square lattice and each spin is allowed to flip under a Monte Carlo probability. The simulation shows that, for the antiferromagnetic coupling, the spins of the particles in clusters tend to be oriented alternately. For the ferromagnetic coupling, however, the spin distribution depends on the exponent α: for large value of α, domains with different sizes are observed in the clusters; while for small α, during the earlier stage of the growth process, the clusters exhibit approximately antiferromagnetic structure, then, in subsequent growth of the outer part of the clusters, the spin states of all particles are similar. The magnetization and system energy of the clusters as well as their evolutions with the growth parameters are also studied in detail. 相似文献
The nonlinear dynamic response and active vibration control of the piezoelectric functionally graded plate are analyzed in this paper. Based on higher-order shear plate theory and elastic piezoelectric theory, the nonlinear geometric and constitutive relations of the piezoelectric functionally graded plate are established, and then the nonlinear motion equations of the piezoelectric functionally graded plate are obtained through Hamilton's variational principle. The nonlinear active vibration control of the structure is carried out with adoption of the negative velocity feedback control algorithm. By applying finite difference method, the whole problem is solved by using iterative method synthetically. In numerical examples, the effects of mechanical load, electric load, the volume fraction and the geometric parameters on the dynamic response and vibration control of the piezoelectric FGM plate are investigated. 相似文献
We theoretically deduce the macroscopic symmetry constraints for arbitrary odd-order nonlinear susceptibilities in homogeneous media including atomic vapors for the first time. After theoretically calculating the expressions using a semiclassical method, we demonstrate that the expressions for third- and fifth-order nonlinear susceptibilities for undressed and dressed four- and six-wave mixing (FWM and SWM) in atomic vapors satisfy the macroscopic symmetry constraints. We experimentally demonstrate consistence between the macroscopic symmetry constraints and the semiclassical expressions for atomic vapors by observing polarization control of FWM and SWM processes. The experimental results are in reasonable agreement with our theoretical calculations. 相似文献
We demonstrate that accessible solitons described by an extended Schrödinger equation with the Laplacian of fractional dimension can exist in strongly nonlocal nonlinear media. The soliton solutions of the model are constructed by two special functions, the associated Legendre polynomials and the Laguerre polynomials in the fraction-dimensional space. Our results show that these fractional accessible solitons form a soliton family which includes crescent solitons, and asymmetric single-layer and multi-layer necklace solitons. 相似文献
The “far‐field” surface plasmon resonance (FSPR) of metal nanoparticles, which have built a facile way to emission enhancement of red, green, blue, and white with nice reproducibility, has big potential application in solution‐processed organic light‐emitting diodes (OLEDs). According to the theory of the “far‐field” effect, the reflectivity of the metal surface and the phase shift at the reflection play an important role in enhancing ratio, which strongly relate to the size and shape of nanoparticles. In this work, gold nanospheres with different sizes and nanorods are synthesized in order to determine the size and shape effect of FSPR. The results demonstrate that the one with higher reflectivity in a certain range induces a better emission enhancement in the luminous efficiency and the maximum brightness. The nanoparticles with bigger sizes and shape of rods have higher reflectivity, which is consistent with the simulation based on FSPR effect. The phase shifts of different nanoparticles are optimized by the distance between gold nanoparticles and emitters. The metal NPs with a high reflectivity and the applicable phase shift will have big potential for the emission enhancement in OLEDs. 相似文献