香气的分维

本文用分形数学理论解释调香行为,计算了香精主题香气奇怪吸引子的分维,总结出“分维越接近1,香精的主题香气就越突出”的结论。通过一系列的计算确认配制香精时用较多种相关香料的有利之处。文中也讨论了香料中“杂气”对主题香气的影响。     

Fractal Benzenoids

The possibility of fractal benzenoids built upon a (deterministically) regular self-similar structure are proposed. Of various possibilities considered a simpler class of “trigonal” structures is identified. Possible directed synthetic schemes are described. Further, Kekulé structure counts are made as well as conjugated-circuits estimates of resonance energies. Results, for the general trigonal class as well as for particular cases are given.     

分形论在无机材料研究中的应用

介绍了分形论在无机材料表面研究、无机薄膜材料、梯度功能材料及无机材料断裂研究等方面的应用情况,并展望了其在玻搪材料中的应用前景.     

TEM characterization of diblock copolymer templated iron oxide nanoparticles: Bulk solution and thin film surface doping approach

The morphology of a novel diblock copolymer, poly(norbornene methanol)-b-poly(norbornene dicarboxylic acid), was investigated before and after metal oxide doping by transmission electron microscopy (TEM) using a novel iodine vapor staining method to image the undoped polymer. A lamellar morphology was observed by TEM after staining the undoped diblock copolymer with iodine vapor. Thin film surface doping resulted in a confinement of the iron oxide nanoparticles within the lamellar domains. Spherical nanoparticle aggregates were observed through a bulk solution doping method. It was observed that the particles were templated by the underlying lamellar structure of the copolymer when the thin film surface doping method was used.     

离心毛管压力曲线分形特征研究

根据分形理论,对某油田区块的离心毛管压力曲线进行分形研究及分形维数的计算结果表明,离心毛管压力曲线具有很好的整体分形特征,比较驱替毛管压力曲线和吸入毛管压力曲线的分维值,发现两者相差很小,具有很好的一致性,说明它们都能较好的描述该区块的孔隙特征;另外,对驱替毛管压力曲线进行分段线性回归后发现,分段分形线性回归相关性好于整体分形,但整体分形更能反映储层岩心的孔隙结构特征。计算的驱替毛管压力分维值和岩样的渗透率有较好的对数关系,和孔隙度具有一定的线性相关性。     

分形BET吸附模型

本文提出了一个改进的分形ＢＥＴ吸附模型。用此模型分析水在新型干燥剂上的吸附平衡和文献［８］中水在活性氧化铝上的平衡吸附数据。结果表明：所提出的模型能在整个相对蒸汽压力范围内描述水在吸附剂上的吸附平衡行为；脱附等温线与吸附等温线之间的差别可归结于吸附质的单层吸附。     

利用分形对无机粒子/高聚物体系分散效果的评定

利用分形的特点，通过自建模型，对原位气泡拉伸法制备的高聚物复合材料的分散效果进行定量分析。实验结果表明，分形维数为0．6～1．3时，颗粒的分散比较均匀，在一定范围内，分形维数越小，分散效果越好。     

CaCO3阻垢剂的分形评价

１前言自从Ｍａｎｄｅｌｂｒｏｔ［‘］在研究不规则形状和过程中提出分形概念以来,分形理论已广泛地应用于自然科学的许多领域。ＣａＣＯ。结晶垢由于在生长过程中受诸多因素的影响,垢表面存在着许多晶体缺陷、凹凸和破语,呈现出复杂的表面形态;阻垢剂的加人,使得ＣａＣＯ３垢晶格发生畸变ｌ‘］,表面不规性增加。并且ＣａＣＯ。结晶垢表面形貌具有自相似的特点,已不能用传统的欧几里德几何加以描述。本文运用分形概念,对模拟循环冷却水系统中常用的ＣａＣＯ。阻垢剂ＰＢＴＣＡ（２一磷酸了烷一ｌ,２,个三核酸）、ＨＥＤＰ（羟基…     

Fractal characteristic of three Chinese coals

Experimental and theoretical investigation about coal/char structure is presented. Surface structures of parent coal and char with different burn-off ratios were analyzed. We introduced the fractal theory into Scanning Electron Microscopy image analysis and utilize the particle surface fractal dimension (D_ps) to quantitatively describe the surface character of coal/char particles. D_ps of three Chinese coals reach their maximum in the 35-45 wt% char burn-off interval and then decrease with increasing carbon burn-off ratio. The inner-pore information of coal/char particles was determined by N₂ isotherm adsorption/desorption. Using fractal BET model, internal surface fractal dimension (D_s) of coal/char particles was calculated. The D_s change trend of three Chinese coals is similar to their S_BET development. It means the D_s can quantitatively describe the inner pore structure character of coal/char particles.     

分形及其在耐火材料研究中的应用

介绍了分形几何学的基本概念及随机分形维数的测定方法。并以O'－Sialon-ZrO2为例，讨论了并在耐火材料研究中的应用。     

滤饼结构的分形研究

概括地介绍了分形理论在滤饼结构研究中的应用 ,并采用电子扫描与计算机图象处理技术 ,并根据分形理论对以平板陶瓷膜为过滤介质的十字流微滤稳态阶段的滤饼结构进行了理论及实验研究。     

Fractal aggregate model of chain with mixed statistics

A fractal aggregate model is presented for chain molecules which are described by different statistics on different length scales. It describes the macromolecular chains as aggregates composed either of non-porous monomers or thermal blobs. The mass of non-porous monomer and the thermal blob mass are both dependent on the solvent quality. The blob mass can be calculated knowing the non-porous monomer mass in a solvent under consideration and that at the theta condition. Both the quantities can be deduced from the solution properties. The values of thermal blob mass normalized by that of monomer, deduced from intrinsic viscosity data for several polymers, form a dependence on Mark-Houvink-Sakurada exponent. This dependence is confirmed by the solvent quality dependence of the polymer mass at the onset of excluded volume behavior and some values obtained from sedimentation coefficients.     

积炭催化剂再生的分形维模型

将分形维理论引入积炭催化剂与再生气体的烧炭反应系统，提出了积炭催化剂的分形维模型。在拟稳态条件下，按缩核模型求得解析解，并在此基础上分析了当反应受气膜扩散控制、灰层扩散控制和化学反应控制时，分形维对再生过程的影响。通过实验和参数估计确定了积炭催化剂表面的分形维数在２～３之间，从而验证了模型的正确性。     

基于分形的纳米复合材料分散相分散均匀性描述

为了描述纳米填料填充复合材料分散相的分散均匀性，提出了一种基于分数布朗运动模型的纳米填料填充复合材料分散相分散均匀性描述方法。该方法将纳米填料填充复合材料TEM图像转化为分散相分布密度矩阵，估计分散相分布密度矩阵的H参数值，提取分散相分布密度波动的分形特征来定量描述分散相分布的均匀性。通过将该方法实际应用于聚合物基纳米填料填充复合材料分散相分散均匀性描述，证明了该方法能够正确描述纳米填料填充复合材料分散相的分散均匀性。     

用分形理论研究低渗储层孔隙结构

储集层岩石的孔隙结构非均质性对于油气的渗流规律以及水驱油效率都具有重要的影响。利用分形理论对孔隙结构的非均质性进行研究。结果表明,分形维数不同孔隙结构不同,所研究的储集层具有单一分形（分形维数2.690 7～2.814 0）和分段分形特征（分形维数2.414 8～2.995 2）;以分形维数为基础,可以根据孔喉渗透率贡献判断孔隙结构的非均质性和复杂程度。     

Characterization of floc size, strength and structure under various coagulation mechanisms

Flocs generated by various coagulation mechanisms exhibit different size, strength and structure. The properties and fractal dimensions of flocs formed under three common coagulation mechanisms, i.e. charge neutralization, sweep and bridging, were investigated at various hydraulic conditions. The results showed that the floc size decreased with the increasing average velocity gradient G and the stable floc size exponent γ was of the following hierarchy: charge neutralization (0.6107) > sweep (0.5618) > bridging (0.3674). Furthermore, fractal dimensions of flocs were the highest when formed by sweep and the lowest when generated by bridging flocculation. The mass fractal dimensions measured by light scattering were between 2.0 and 3.0 and the floc strength was between 0.01 and 0.58 N m^− 2. An intrinsic unity of the relationship among floc size, fractal dimensions, floc strength under the three coagulation mechanisms was demonstrated.     

Fractal Dimensions of Simulated and Real Fat Crystal Networks in 3D Space

The microstructure of fat crystal networks is closely related to rheological properties of fat products, and thus is of particular interest to food scientists. The fractal dimensions of fat crystal networks calculated by microscopy methods such as box-counting, D _b, particle-counting, D _f, and mass fractal dimension, D _m, have been extensively employed to quantify the microstructure of fats. This work revealed the microstructural basis of D _b, D _f, and D _m in 3D space through both computer simulation and experiments on the high melting fraction of milk fat crystal networks. Similar to our previous simulation study on the fractal dimensions of fat crystal networks in 2D space, D _b is sensitive to crystal size, area fraction, and not sensitive to distribution orderliness of crystals, which is the percentage of evenly distributed fat crystals within the simulated fat crystal networks. D _f and D _m were not affected by any of the microstructural factors studied in the simulation.     

Fractal Theory on Drying: A Review

Fractal geometry has been widely used in various dried materials and drying processes. This review summarizes the related studies and identifies the opportunities for future investigation. The application of fractal concept on drying can be categorized into describing microscopic and macroscopic structure of material in drying with fractal geometry and theoretical models with fractal theory for drying mechanism. And also, the capillary and network models for drying of capillary porous media are discussed and a fractal tortuous capillary model for drying of capillary porous media is proposed. From the selected examples, it is clear that the fractal theory has many advantages for identifying the complex structure of products and investigating drying mechanism. At last, some comments are made for the current investigations and also some prospects for the future development of this field are pointed out.     

分形理论分析填料塔内件的发展

综述了乱堆填料、规整填料和气液分布装置的发展概况,应用分形理论分析填料的几何结构对气液传质的影响,并提出了今后填料塔研究的方向。     

Fractal Pore Network Simulation on the Drying of Porous Media

Based on the knowledge of fractal geometry, physics of flow through porous media, and transport process principle, a fractal pore network model for the drying process of a natural porous body was established in this article. This model takes various factors into consideration, such as liquid-phase flow, vapor-phase diffusion, temperature gradient, and pore microstructure characteristic. The drying dynamics characteristics of potato slices were obtained by the simulation of a fractal pore network model. The simulation results of the fractal pore network model were contrasted with those of a regular one and the experimental data, respectively. The wet patches were observed on the potato slices during the drying experiments, and it was validated by the drying simulation. The results indicate that the drying kinetics from the fractal pore network model, as well as the distributions of moisture and temperature inside the porous body, are more consistent with that of the drying experiments than that of the regular one, and the throat size distribution in the pore network of the porous media has a notable influence on the drying process.