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41.
泸州古隆起嘉陵江组油气成藏期的确定   总被引:8,自引:1,他引:7  
通过流体包裹体分析及其均一温度的研究,并结合烃源岩演化史、储层地温史、岩心薄片镜下沥青的观察,按照油气分段捕获原理,确定四川盆地泸州古隆起嘉陵江组油气共存在4次成藏期,即中三叠世、中侏罗世前后、晚白垩世前后和喜山运动中晚期, 分别对应古油藏的形成与破坏期、志留系注气为主期、二叠系注气为主期和油气再分配期。同时,根据储层沥青在镜下的光学特征和在各类孔隙中的分布形态的观察,可定性确定泸州古隆起嘉陵江组油气存在多期注入和叠加的历史,并证实泸州古隆起核部曾经存在一个来自志留系烃源的印支期古油气藏。结果表明,综合考虑多种因素,应用流体包裹体确定油气成藏期的方法行之有效。  相似文献   
42.
本文介绍了5MW 低功率堆(5MW LPR)主屏蔽辐射场和温场的计算模型、方法和程序,给出了修改设计的主要计算结果。混凝土屏蔽层内表面的入射中子通量和γ通量均满足设计标准规定。最高温度、最大温升及最大温度梯度亦均符合规定要求。为证明温场程序的可靠性,将HFETR 混凝土屏蔽层内温度计算值与实测值作了比较,结果符合得很好。  相似文献   
43.
A homogenization technique was developed and presented to replace a discrete atomic domain by an equivalent continuum domain that could be discretized into finite elements. Equivalent material properties of the smeared continuum domain were computed from the atomic model. Using the developed technique, a computationally efficient analysis could be performed for a large size of domain by proper mixture of a discrete atomic region and a smeared continuum region. In addition, this technique provided a means for multi-scale analysis. Examples for static and dynamic analyses were provided to demonstrate the technique.  相似文献   
44.
In this paper, the power consumption, the vertical local void fraction and the local gas–liquid interfacial area are investigated in the aerated stirred tank reactors(STRs) equipped with a rigid-flexible impeller. Meanwhile, the regressive correlation based on power consumption and interfacial area is proposed. Then a novel homogenization energy(HE = RSDPtm) expression based on power consumption and local interfacial area is redefined and used to indicate the mixing efficiency. The optimal operating mode is selected based on the change of the HE value. This paper can provide research ideas for structural optimization of stirred reactors.  相似文献   
45.
The effects of microfluidization at 150 MPa (MFz) and conventional homogenization at 20/5 MPa (CH) of heat-treated milk on the rheology and sensory properties of non- (0.1%) and low- (1.5%) fat stirred yoghurts were compared. Homogenization conditions clearly affected the sensory properties of reduced-fat yoghurts, but the effect was highly dependent on fat content. MFz of heat-treated milk yielded products with very different sensory profiles from the conventional yoghurts. For non-fat yoghurts, MFz of heat-treated milk enhanced the perception of buttermilk and soft cheese flavours, and natural yoghurt aroma and flavour, but also increased the intensity of undesirable mouthfeel characteristics such as chalkiness, mouth-dryness and astringency. For low-fat yoghurts, MFz significantly improved creaminess and desirable texture characteristics such as smoothness, cohesiveness, thickness, and oral and spoon viscosity. These differences in sensory profiles, especially textural properties, were partially related to rheological properties, particularly flow behaviour. MFz of heat-treated milk resulted in non- and low-fat yoghurts with higher yield stress, more pronounced hysteresis effect and higher viscosity than those of CH yoghurts of similar fat contents. These findings suggest that microfluidization may have applications for production of high-quality yoghurt with reduced-fat content.  相似文献   
46.
Even if a ceramic's homogenized properties (such as anisotropically evolving stiffness) truly can be predicted from complete knowledge of sub-continuum morphology (e.g., locations, sizes, shapes, orientations, and roughness of trillions of crystals, dislocations, impurities, pores, inclusions, and/or cracks), the necessary calculations are untenably hypervariate. Non-productive (almost derailing) debates over shortcomings of various first-principles ceramics theories are avoided in this work by discussing numerical coarsening in the context of a pedagogically appealing buckling foundation model that requires only sophomore-level understanding of springs, buckling hinges, dashpots, etc. Bypassing pre-requisites in constitutive modeling, this work aims to help students to understand the difference between damage and plasticity while also gaining experience in Monte-Carlo numerical optimization via scale-bridging that reduces memory and processor burden by orders of magnitude while accurately preserving aleatory (finite-sampling) perturbations that are crucial to accurately predict bifurcations, such as ceramic fragmentation.  相似文献   
47.
《Ceramics International》2022,48(9):11998-12005
In this study, basalt from a base in Hebei, China, was selected as the raw material. Water-quenched basalt glasses and basalt fibers were prepared at different homogenization times and temperatures. The water-quenched glass structure was characterized by XRD and a Raman spectrometer followed by fitting of their Raman spectra by Gaussian curves to obtain information about melt structure. The fiber performance was characterized by fiber strength meter and fiber fineness meter. The results demonstrate that homogenization time and temperature had significant effects on the structure of basalt melt. The degree of polymerization of the melt increased with increasing homogenization time and decreased with increasing homogenization temperature. The fiber strength increased with increasing the degree of polymerization. As the homogenization time and temperature increased, coefficients of variation of fiber strength and fiber diameter decreased, indicating enhanced fiber stability.  相似文献   
48.
Circular footings resting on geotextile-reinforced sand bed   总被引:1,自引:0,他引:1  
The note pertains to an experimental study made on circular footings resting on semi-infinite layer of sand reinforced with geotextiles. Using the concept of homogenization of such soils, both analytical and numerical analyses have also been conducted to predict the load-settlement behavior and compared with experimental observations. The study highlights the effect of the footing size, number of reinforcing layers, reinforcement placement pattern and bond length and the relative density of the soil on the load-settlement characteristics of the footings.  相似文献   
49.
The macroflow of fluid in a tall cylindrical vessel stirred with multiple stirrers was studied in the case of aeration of a liquid charge. The time of homogenization of the charge (mixing time) was calculated from the time dependency of the tracer concentration measured at various locations. Two types of stirrer were used in the experiments: six‐bladed Rushton turbines and/or pitched‐blade turbines with inclined blades pumping the liquid down or up. Four stirrers of the same type were located on the shaft. Other variables during the experiments were the stirrer frequency and the gas flow rate. It was found that the liquid macroflow in the vessel could be interpreted by the cell model or by the axial dispersion model for unaerated as well as for aerated systems. The influence of the aeration on the macroflow and mixing time was explained by the interaction of buoyancy and radial forces, and equations for the model parameters were proposed containing gas flow numbers and Froude numbers.  相似文献   
50.
This article provides a systematic study of the impact of different thermal treatments (62 ± 2°C, without and with relative humidity control, 79%) on soy protein in defatted soy flour and their aqueous dispersions. The effect of dispersing treatments (magnetic stirring, high-speed, and high-pressure homogenization) on dispersions also was assessed. Changes in protein solubility (water and 0.2 g/100 g potassium hydroxide solution), apparent-reactive lysine content, urease and trypsin inhibitor activities, protein denaturation, and Fourier transform infrared spectra were studied. Glycosylation, aggregation, and denaturation of storage and biologically active soy proteins were observed in different degrees, being mainly promoted by the control of relative humidity and the dispersibility of the sample.  相似文献   
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