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Pore structure is a crucial attribute in characterizing fluid flow through porous media. However, direct experimental measurements or numerical reconstructions are commonly expensive and not environmentally friendly, with great uncertainty caused by the complex nature of porous media. In this study, we demonstrate that one special bridge function, which is a function of the apparent length and tortuosity fractal dimension, can characterize the relationship of pore structures between two dimensions (2‐D) and three dimensions (3‐D), and it can serve as a conversion bridge of the radius to determine the capillary pressure curve (CPC). We compare estimations by the proposed method with experimental results obtained by mercury intrusion porosimetry in six typical natural sandstones with varying porosities and permeabilities. The result shows that cross sections of the global pore structure, such as thin section, electronic probe, and microcomputed tomography slices, give a reliable estimation of the CPC using the bridge function in porous media with a medium porosity. However, in unconventional porous media with a relatively low porosity (~10%) or extra high porosity (~30%), due to the empirical nature of the equation widely used to calculate the tortuosity fractal dimension, the necessary modification is necessary to obtain the CPC when applying the bridge function in such porous media. This insight can significantly simplify the procedure for obtaining the petrophysical properties of a porous medium, which may shed light on the inherent differences and correlations between the 2‐D and 3‐D pore structures of porous media.

Integrated microfluidic systems afford extensive benefits for chemical and biological fields, yet traditional, monolithic methods of microfabrication restrict the design and assembly of truly complex systems. Here, a simple, reconfigurable and high fluid pressure modular microfluidic system is presented. The screw interconnects reversibly assemble each individual microfluidic module together. Screw connector provided leak-free fluidic communication, which could withstand fluid resistances up to 500 kPa between two interconnected microfluidic modules. A sample library of standardized components and connectors manufactured using 3D printing was developed. The capability for modular microfluidic system was demonstrated by generating sodium alginate gel microspheres. This 3D printed modular microfluidic system makes it possible to meet the needs of the end-user, and can be applied to bioassays, material synthesis, and other applications.

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The effect of the anisotropic interfacial energy on dendritic growth has been an important subject, and has preoccupied many researchers in the field of materials science and condensed matter physics. The present paper is dedicated to the study of the effect of full 3-D anisotropic surface tension on the steady state solution of dendritic growth. We obtain the analytical form of the first order approximation solution in the regular asymptotic expansion around the Ivantsov's needle growth solution, which extends the steady needle growth solution of the system with isotropic surface tension obtained The solution is expanded in the general Laguerre series in any finite region around the needle-tip, and it is also expanded in a power series in the far field behind the tip. Both solutions are then numerically matched in the intermediate region . Based on this global valid solution, the dependence of Peclet number Pe and the interface's morphology on the anisotropy parameter of surface tension as well as other physical parameters involved are determined. On the basis of this global valid solution, we explore the effect of the anisotropy parameter on the Peclet number of growth, as well as the morphology of the interface. ½ ÁÒØÖÓ Ù Ø ÓÒIn studying free dendritic growth, the effect of anisotropic interfacial energy on pattern formation and selection bas been an important subject, which has preoccupied many researchers in the field of materials science and condensed matter physics for quite a long time now [1][2][3][4]. During the past decades, most theoretical investigations on this subject were focused on the system of 2-D dendritic growth with anisotropy of surface tension, or the system of 3-D axi-symmetric dendritic growth with axial anisotropy of surface tension, neglecting the three dimensionality of the anisotropy of surface tension [5][6][7][8][9][10][11][12][13][14][15]. With these efforts, the effect of the anisotropy of surface tension on the morphology of the steady state, interfacial stability mechanisms and selection of dendritic pattern formation for 2-D systems are now well explored analytically.A realistic system of dendritic growth is always three dimensional. The anisotropy of surface tension at the interface is also three dimensional. Up to now in literature, there are very few analytical works on dendritic growth in systems with full 3-D anisotropic surface tension. As a consequence, the effects of three dimensionality of anisotropy on the steady state solution as well as the stability mechanisms of dendritic growth are still unclear.In order to explore the effect of 3-D anisotropic surface tension on the stability mechanisms and the selec-