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41.
T.L.-G. Carlson K. Larsson Y. Miezis 《Journal of Dispersion Science and Technology》2013,34(2):197-208
In connection with studies of technical functionality of lipids in cereals, the aqueous systems of lipids from rye and tri-ticale flour are described and compared to different wheat culti-vars. Rye lipids give a lamellar liquid-crystalline phase with very small ordered regions, and this phase is continuously changed into an L2-phase with increasing water content. Triticale lipids exhibit phase equilibria in between lipids of wheat and of rye. Evidence is given for a significant role of the lamellar liquid--crystalline phase with regard to technical functionality when the cereal flour is worked in water to give a dough. 相似文献
42.
B. W. Bailey J. M. Rankin R. Weinbloom 《International journal of environmental analytical chemistry》2013,93(1):3-9
The use of ternary complexes in the determination of anionic surfactants has been investigated and an analytical method using linear alkyl sulfonates as a test substance has been developed. The method involves the formation of the chloroform-extractable bisphenanthroline Cu(II)-linear alkyl sulfonate (LAS) complex and the subsequent equilibration of the extract with erythrosine to form the extractable bisphenanthroline Cu(II)-erythrosine complex. In the equilibration step erythrosine displaces LAS quantitatively, allowing the determination of the LAS originally present by measuring the absorbance of the extracted bisphenanthroline-Cu(II)-erythrosine complex. Results are reported of studies made to determine the optimum analytical conditions, the sensitivity, and the precision for the method described. 相似文献
43.
44.
利用水热法制备了菊花状的氧化锌纳米棒,并进行表征,将纳米氧化锌掺入纳米金刚石中配制成电泳液,超声分散后电泳沉积到钛衬底上,再经热处理后进行场发射特性的测试.结果表明:未掺混的金刚石阴极样品的开启电场为7.3V/μm,在20V/μm的电场下,场发射电流密度为81μA/cm2;掺混后阴极样品的场发射开启电场降低到4.7~6.0V/μm,在20V/μm电场下,场发射电流密度提高到140~158μA/cm2.原因是纳米ZnO掺入后,增强了涂层的电子输运能力、增加了有效发射体数目,提高了场增强因子β,而金刚石保证了热处理后涂层与衬底的良好键合,形成了欧姆接触,降低了场发射电流的热效应.场发射电流的稳定性随掺混ZnO量的增加而下降,要兼顾场发射电流密度及其稳定性,适量掺入ZnO可有效提高纳米金刚石的场发射性能. 相似文献
45.
In this work, an analytical model of gate-engineered junctionless surrounding gate MOSFET (JLSRG) has been proposed to uncover its potential benefit to suppress short-channel effects (SCEs). Analytical modelling of centre potential for gate-engineered JLSRG devices has been developed using parabolic approximation method. From the developed centre potential, the parameters like threshold voltage, surface potential, Electric Field, Drain-induced Barrier Lowering (DIBL) and subthershold swing are determined. A nice agreement between the results obtained from the model and TCAD simulation demonstrates the validity and correctness of the model. A comparative study of the efficacy to suppress SCEs for Dual-Material (DM) and Single-Material (SM) junctionless surrounding gate MOSFET of the same dimensions has also been carried out. Result indicates that TM-JLSRG devices offer a noticeable enhancement in the efficacy to suppress SCEs by as compared to SM-JLSRG and DM-JLSRG device structures. The effect of different length ratios of three channel regions related to three different gate materials of TM-JLSRG structure on the SCEs have also been discussed. As a result, we demonstrate that TM-JLSRG device can be considered as a competitive contender to the deep-submicron mainstream MOSFETs for low-power VLSI applications. 相似文献
46.
We propose a scheme for a topological insulator field effect transistor. The idea is based on the gate voltage control of the Dirac fermions in a ferromagnetic topological insulator channel with perpendicular magnetization connecting to two metallic topological insulator leads. Our theoretical analysis shows that the proposed device displays a switching effect with high on/off current ratio and a negative differential conductance with a good peak to valley ratio. 相似文献
47.
Theoretical analysis of the local orientation effect and the lift‐hyperlayer mode of rodlike particles in field‐flow fractionation 下载免费PDF全文
We investigated theoretically the effects of the cross‐stream migration and the local average orientation of rodlike particles on the shape‐based separation using field‐flow fractionation. The separation behavior was analyzed by comparing the retention ratios of spheres and rods. The retention ratio of a rod was evaluated through the derivation of its cross‐sectional concentration profile by considering the rod migration and the local average orientation. Our study in various flow conditions showed that the rod migration, caused by the hydrodynamic interaction with a wall, can affect the separation behavior as a lift‐hyperlayer mode. We also demonstrated that the local average orientation, which is a function of a local shear rate and a rotational diffusivity, results in the transverse diffusivity that is different from its perpendicular diffusivity. These results suggest that the experimental separation behaviors of rods in field‐flow fractionation may not be fully explained by the current theory based on the normal mode and the steric mode. We also characterized each condition where one of the normal mode, the steric mode of spheres, and the lift‐hyperlayer mode of rods is dominant. 相似文献
48.
Full field laser Doppler imaging (LDI) and single exposure laser speckle contrast imaging (LSCI) are directly compared using a novel instrument which can concurrently image blood flow using both LDI and LSCI signal processing. Incorporating a commercial CMOS camera chip and a field programmable gate array (FPGA) the flow images of LDI and the contrast maps of LSCI are simultaneously processed by utilizing the same detected optical signals. The comparison was carried out by imaging a rotating diffuser. LDI has a linear response to the velocity. In contrast, LSCI is exposure time dependent and does not provide a linear response in the presence of static speckle. It is also demonstrated that the relationship between LDI and LSCI can be related through a power law which depends on the exposure time of LSCI. 相似文献
49.
Utilizing the unique features of the scanning atom probe (SAP) the binding states of the biomolecules, leucine and methionine, are investigated at atomic level. The molecules are mass analyzed by detecting a single atom and/or clustering atoms field evaporated from a specimen surface. Since the field evaporation is a static process, the evaporated clustering atoms are closely related with the binding between atoms forming the molecules. For example, many thiophene radicals are detected when polythiophene is mass analyzed by the SAP. In the present study the specimens are prepared by immersing a micro cotton ball of single walled carbon nanotubes (SWCNT) in the leucine or methionine solution. The mass spectra obtained by analyzing the cotton balls exhibit singly and doubly ionized carbon ions of SWCNT and the characteristic fragments of the molecules, CH3, CHCH3, C4H7, CHNH2 and COOH for leucine and CH3, SCH3, C2H4, C4H7, CHNH2 and COOH for methionine. 相似文献
50.
T. Rado 《Progress in Surface Science》2001,67(1-8):339-346
A novel procedure for the investigation of optical excitations on the metal surface by the photofield emission method is reviewed. A separation procedure of thermocurrent, accompanying the measured photocurrent, induced by the chopped light beam, is described. A differentiation of the true photocurrent curve allows one to obtain an energy distribution of photoelectrons. For the (0 0 0 1) face of Ti, it exhibits very small and densely spaced maxima, confirmed by theory as surface resonances. The dependence of the density on the thickness of the Ti crystal, grown by evaporation of Ti on the W field emitter surface, was verified experimentally. The possibility of observing surface resonances on a microcrystal of a homogeneous field emitter is discussed. 相似文献