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11.
A Hilbert transform for Hlder continuous circulant (2 × 2) matrix functions, on the d-summable (or fractal) boundary Γ of a Jordan domain Ω in R2n , has recently been introduced within the framework of Hermitean Clifford analysis. The main goal of the present paper is to estimate the Hlder norm of this Hermitean Hilbert transform. The expression for the upper bound of this norm is given in terms of the Hlder exponents, the diameter of Γ and a specific d-sum (d d) of the Whitney decomposition of Ω. The result is shown to include the case of a more standard Hilbert transform for domains with left Ahlfors-David regular boundary.  相似文献   
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13.
Soy protein isolate (SPI) powders often have poor water solubility, particularly at pH values close to neutral, which is an attribute that is an issue for its incorporation into complex nutritional systems. Therefore, the objective of this study was to improve SPI solubility while maintaining low viscosity. Thus, the intention was to examine the solubility and rheological properties of a commercial SPI powder at pH values of 2.0, 6.9, and 9.0, and determine if heat treatment at acidic or alkaline conditions might positively influence protein solubility, once re-adjusted back to pH 6.9. Adjusting the pH of SPI dispersions from pH 6.9 to 2.0 or 9.0 led to an increase in protein solubility with a concomitant increase in viscosity at 20 °C. Meanwhile, heat treatment at 90 °C significantly improved the solubility at all pH values and resulted in a decrease in viscosity in samples heated at pH 9.0. All SPI dispersions measured under low-amplitude rheological conditions showed elastic-like behaviour (i.e., G′ > G″), indicating a weak “gel-like” structure at frequencies less than 10 Hz. In summary, the physical properties of SPI can be manipulated through heat treatment under acidic or alkaline conditions when the protein subunits are dissociated, before re-adjusting to pH 6.9.  相似文献   
14.
In this study, wood production and hydrologic functions of forests were accommodated within a planning procedure for separate working circles (areas dedicated to certain forest functions) that were delineated according to an Ecosystem‐Based Functional Planning approach. Mixed integer goal programming was used as the optimization technique. The timing and scheduling of a maintenance cutting (partial harvest) was the decision variable in the modeling effort, and an original formulation was developed as a multiobjective planning procedure. Four sample planning strategies were developed and model outputs were evaluated according to these strategies. Spatial characteristics of stands were considered, and used to prohibit the regeneration of adjacent stands during the same time period. Because of the positive relationship between qualified water production and standing timber volume in the forest, the model attempts to maximize qualified water production levels by increasing standing volume stocks in the forest through the delay of regeneration activities.  相似文献   
15.
Owing to their diverse range of highly tailorable material properties, inorganic/organic hybrids have the potential to meet the needs of biodegradable porous scaffolds across a range of tissue engineering applications. One such hybrid platform, the silica–gelatin sol–gel system, was examined and developed in this study. These hybrid scaffolds exhibit covalently linked interpenetrating networks of organic and inorganic components, which allows for independent control over their mechanical and degradation properties. A combination of the sol–gel foaming process and freeze drying was used to create an interconnected pore network. The synthesis and processing of the scaffolds has many variables that affect their structure and properties. The focus of this study was to develop a matrix tool that shows the inter-relationship between process variables by correlating the key hybrid material properties with the synthesis parameters that govern them. This was achieved by investigating the effect of the organic (gelatin) molecular weight and collating previously reported data. Control of molecular weight of the polymer is as an avenue that allows the modification of hybrid material properties without changing the surface chemistry of the material, which is a factor that governs the cell and tissue interaction with the scaffold. This presents a significant step forward in understanding the complete potential of the silica–gelatin hybrid system as a medical device.  相似文献   
16.
保护渣元素的定量分析一般采用传统的湿法化学分析 ,化学分析虽然准确度好 ,但难以做到快速且劳动量大。利用 X-射线荧光光谱法分析保护渣中各元素含量是一种快速、准确的分析方法 ,在国外已得到广泛应用。本文从现场分析的实际出发 ,选择融样条件、最佳仪器参数 ,用基准物质合成标准样品 ,绘制标准工作曲线 ,曲线线性良好 ,用化学分析法对荧光分析值进行验证 ,结果符合化学允许差。1 试验部分1 .1 仪器设备、试剂及工作条件MXF2 1 0 0 - X-射线荧光光谱仪TR- AUTO- BEAD- 1 0 0 0 S/W熔融炉混合熔剂 :4g四硼酸钠 +4g四硼酸锂 +0 .…  相似文献   
17.
本文首次报道以690.0~715.0nm宽波段范围内任何波长的脉冲染料激光激发K_2—K系统,由高位钾分子与钾原子碰撞以及分子-原子的混合激发等过程而产生钾原子404.4,404.7和470.05~590.0nm波段内高位态辐射的实验结果,并对激发机制进行了探讨.  相似文献   
18.
We construct two cohomological invariants associated to pairs of Lagrangian sub-bundles of a symplectic bundle on a compact manifold upon which a compact Lie group is acting. The first invariant, which we call the classical equivariant Maslov H-invariant, provides an obstruction to Lagrangian transversality and lives in the Borel cohomology. The second invariant, which we call the equivariant Maslov U-invariant, generalises the author's results in K-Theory 13 (1998), 347–361 to the equivariant context and provides a necessary and sufficient condition for equivariant Lagrangian transversality, up to homotopic stability, and lives in the U-theory (intermediate between the real complex K-theories). As an application, we show that two Lagrangian sub-bundles of a symplectic bundle on a homogeneous space are always stably transverse.  相似文献   
19.
In this paper we consider the fixed finite-order digital linear-quadraticcontrol of Pritchard-Salamon infinite-dimensional systems withunbounded input and output operators under gaussian disturbances.A set of necessary conditions is given in terms of the solvabilityof a discrete-time Hyland-Bernstein system of equations (twomodified Riccati equations and two modified Lyapunov equationscoupled by an projection operator).  相似文献   
20.
The main focus of this work is to model macroscopically the effects of partial saturation upon the permeability of dual scale fibrous media made of fiber bundles when a Newtonian viscous fluid impregnates it. A new phenomenological model is proposed to explain the discrepancies between experimental pressure results and analytical predictions based on Darcy's law. This model incorporates the essential features of relative permeability but without the necessity of measuring saturation of the liquid for its prediction. The model is very relevant for the small scale industrial systems where a liquid is forced to flow through a fibrous porous medium. It requires four parameters. Two of them are the two permeability values based on the two length scales. One length scale is of the order of magnitude of the individual fiber radius and corresponds to the permeability of the completely staurated medium, the other is of the order of magnitude of the distance between the fiber bundles and corresponds to the permeability of the partially saturated medium. The other two parameters are the lengths of the two partially saturated regions of the flow domain. The two lengths of the partially saturated region and the permeability of the fully saturated flow domain can be directly measured from the experiments. The excellent agreement between the model and the experimental results of inlet pressure profile with respect to time suggests that this model may be used to describe the variation of the permeability behind a moving front in such porous media for correct pressure prediction. It may also be used to characterize the fibrous medium by determining the two different permeabilities and the relative importance of the unsaturated portion of the flow domain for a given architecture.  相似文献   
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