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1.
A model is presented for drying of a single porous particle with superheated steam and humid air. Experimental data for spherical porous ceramic particle reported in the literature were used for the validation of the model. An inversion temperature at which the evaporation rates within superheated steam and humid air are equal was predicted. The effect of thermophysical properties of the particle (permeability 10-14 - 10-17 m2, diameter 3 × 10-3 - 10 × 10-3 m) and operating variables (gas mass flux 0.26 - 0.78 kg m-2 s-1, drying agent temperature 120-200°C) is tested. The inversion temperature is shown to be affected by the thermophysical properties of the porous particle and of the drying agent.  相似文献   
2.
Imperative programs can be inverted directly from their forward-directed program code with the use of logical inference. The relational semantics of imperative computations treats programs as logical relations over the observable state of the environment, which is taken to be the state of the variables in memory. Program relations denote both forward and backward computations, and the direction of the computation depends upon the instantiation pattern of arguments in the relation. This view of inversion has practical applications when the relational semantics is treated as a logic program. Depending on the logic programming inference scheme used, execution of this relational program can compute the inverse of the imperative program. A number of nontrivial imperative computations can be inverted with minimal logic programming tools.  相似文献   
3.
最大熵在感应测井反演中的应用   总被引:1,自引:0,他引:1  
朱军  张庚骥 《测井技术》1992,16(6):441-450,462
常规的反演方法是对感应测井资料进行线性反褶积。由于感应测并获得的响应曲线是地层非线性时变滤波的结果,感应测井响应随地层电导率发生非线性变化。本文把熵的概念引入到感应测井反演中。用最大熵方法分别设计出实部信号和虚部信号所对应的反滤波因子,两条反映测井响应随电导率非线性变化的非线性函数也被拟合出来。文章最后用设计出的滤波因子及被拟合出的非线性函数对模拟相量感应测井资料进行了相量反褶积。处理结果表明,围岩效应和趋肤效应基本被消除。本方法与常规的三点反褶积法相比,克服了过聚焦现象,提高了精度。  相似文献   
4.
重型血友病甲基因诊断新技术的研究及其应用   总被引:7,自引:1,他引:6  
远用长距离DNA扩增技术成功地检测出凝血八因子FⅧ基因倒位缺陷患者,并检出该倒位的女性携带者。  相似文献   
5.
Inversion of sucrose is a stability problem particularly of candies with acidic taste that contain sucrose and small amounts of organic acids such as citric acid, since the free d-fructose produced by hydrolysis is hygroscopic. The following possibilities were investigated for preventing the hydrolysis of sucrose in tablets containing sucrose and citric acid: Adding various amounts of tri-sodium citrate to the formulation to neutralize the citric acid, (Hot) melt coating of citric acid and tri-sodium citrate with a vegetable fat at different coating ratios, variation of the ratio of coated citric acid and tri-sodium citrate in formulations, and compressing the formulations with different compression forces. After tablet processing and storage of tablets, the concentration of d-fructose was determined on the basis of enzymatic reactions. A response surface central composite design was used. The above-mentioned variations were chosen as independent variables and the amount of d-fructose was chosen as response variable. The lowest rates of inversion could be achieved by increasing the content of tri-sodium citrate and the ratio of coating material and decreasing the ratio of coated citric acid and tri-sodium citrate in the tablet formulations. The compression force had no significant effect on the inversion of sucrose.  相似文献   
6.
CFRP压力容器固化成型过程中边界条件的确定   总被引:1,自引:5,他引:1  
文中应用总放热系数等效考虑了CFRP压力容器固化过程中热压釜辐射与对流边界条件。将有限元法引入瞬态热传导的反问题,根据试验测量的温度曲线,并结合最优化理论确定合理的热压釜热边界条件。结果表明:平板试验得到了总放热系数序列,其计算温度与测试温度的最大温差为0.147℃。由此,可以将得到的总放热系数序列作为CFRP压力容器固化成型过程的等效热边界条件,为其固化成型的数值模拟提供计算基础。  相似文献   
7.
A D-Phenylalanine (Phe) imprinted terpolymer, Polyacrylonitrile-Poly(acrylic acid)-Poly(acryl amide) (Poly(AN-AA-AAm)) bead was prepared by the wet-phase inversion method. Acrylamide (AAm) and acrylic acid (AA) were used as the functional monomer and acrylonitrile (AN) was used as a physical cross linker. The characteristics of selective adsorption by the D-Phe imprinted terpolymer beads were investigated at high concentrations of Phe racemate solution, 1 g Phe/L, and 10 g Phe/L. The adsorption selectivity of the D-Phe imprinted terpolymer beads prepared by anin-situ implanting method reached 0.82 and 0.8 at 1.0 g and 10 g Phe/L racemate solution, respectively, and almost all of the adsorbed D-Phe and about 43% of the adsorbed L-Phe were desorbed by 4% acetic acid. The uptake capacities of the terpolymer beads were maintained for several repeated batches.  相似文献   
8.
In this paper, the inversion processing of cascade impactor data to construe continuous size distributions within fine particulate matter (PM2.5) is examined for residential oil furnace and fireplace appliance emissions. Impactor data from tests with these emissions sources are selected for the challenges they pose to comprehending the size distributions of aerosol mass and chemical species. In specific, the oil furnace aerosol offers an opportunity to apply data inversion to study a bimodal lognormal distribution in which much of the aerosol mass is impactor-penetrating nanoparticles . The fireplace emissions on the other hand cover the issue of a chemical size distribution, which is subject to particle loss and characterized by a single lognormal, accumulation mode peak. Computational steps relevant to the application of the data inversion are illustrated in detail. Evaluation of correlation coefficients (0.992) indicates that the inversion model predictions fit the impactor data well. Simulations of systematic measurement error (±10%) at each impactor stage are shown to have a negligible impact on the inversion results for test data. It is concluded that data inversion can be effective when (i) source emissions contain a portion of particles that falls outside the measurement range of cascade impactors, (ii) a mass size distribution of an individual species is determined without the knowledge of the total mass concentration for that species, or when (iii) losses in the particle charger system are significant.  相似文献   
9.
现阶段地球物理三维勘探面临越来越复杂的问题,其要求更精细的三维网格剖分,现有的一些方法随着网格节点的增加其收敛速度相应减慢。对于应用中更复杂实际模型、更细密网格剖分以及更快收敛速度要求,难于有进一步提高。要有所突破,需借助计算数学最新进展,引入新的高效算法。多重网格法是近二十年迅速发展的一种求解微分方程近乎最优的新算法。本文首先简单介绍了多重网格法基本原理和运算格式,着重介绍了当前国内外多重网格法在地球物理正反演中的应用成果和发展现状。此外,对多重网格法在地球物理正反演中的应用前景及发展趋势进行了展望。  相似文献   
10.
以古地貌分析、砂体展布特征为指导,开展了潜江凹陷建新地区多种技术手段的地震储层预测研究。结果表明,振幅类与波形类属性是该区的敏感性参数,并且通过本地区的岩石物理分析,认为波阻抗也能较好地区分储层;在刻画储层展布形态的同时与构造相叠合落实了多个构造-岩性圈闭,进一步明确该区构造-岩性油藏的勘探潜力。  相似文献   
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