The axial homogeneity of preparative-scale chromatography columns was studied by measuring the overall properties of similar columns differing only by their lengths. The properties investigated were the packing density, the external porosity, the permeability and the column efficiency. Two different materials were used, one made of large, irregular silica particles compressed under either high ...

introduction: gloves protect the dental healthcare worker from direct contact with microorganisms in the patient's mouth and on dental setting surfaces; they also protect the patient from potential pathogens on the hands of the clinicians. this study was performed to evaluate the permeability of three types of examination latex gloves after treatment of patients in pediatric department of mashh...

This paper proposes a mechanism called the mode-switching model that is presented as an alternative to fault-valve model. relevant open-flow, low-porosity, fluid-saturated systems deforming by pressure solution creep. As opposed most constitutive models discussed in geological literature, yield envelope capped at high normal stresses, demonstrated experimental studies. A low-permeability rock h...

The aim of this research was to study the effect of various water-to-cement ratio on the properties of pervious concrete. Tests were carried out to find the optimum water-to-cement ratio that gives a high compressive strength with acceptable permeability. The tests of fresh density, compressive strength at 7days, porosity and water permeability for four mixes of pervious concrete with various w...

Geo-materials such as vuggy carbonates are known to exhibit multiple spatial scales. A common manifestation of spatial scales is the presence of (at least) two different scales of pores, which is commonly referred to as double porosity. To complicate things, the pore-network at each scale exhibits different permeability, and these networks are connected through fissure and conduits. Although so...

The substitution of matrix permeability for fracture permeability to simplify the simulation of complex fracture systems requires a radically different treatment of transport in the matrix. The spatial distribution of pressure is reasonably well described by inclusion of only the major fractures. Transport of tracer and heat, however, depends on a detailed knowledge of fluid velocities. These v...

Tedious calculations and simulations are needed to obtain an efficient production scenario and/orproper field development strategy. Capacitance-resistance model (CRM) is proved to be a fastreservoir simulation tool using just the field-available data of production and injection rates. Thisapproach sets a time-constant and a weighting factor (or well-pair connectivity parameter...

This paper proposes a two-step approach for characterizing the reservoir properties of the world’s largest non-associated gas reservoir. This approach integrates geological and petrophysical data and compares them with the field performance analysis to achieve a practical electrofacies clustering. Porosity and permeability prediction is done on the basis of linear functions, succeeding the elec...

1 Flow in deformable porous media I 2 Abstract Many processes in the earth, such as magma migration, can be described by the ow of a low viscosity uid in a viscously deformable, permeable matrix. The purpose of this and a companion paper is to develop a better physical understanding of the equations governing these two-phase ows. This paper presents a series of analytic approximate solutions to...

The failure mode of lava-dilatant or compactant-depends on the physical attributes of the lava, primarily the porosity and pore size, and the conditions under which it deforms. The failure mode for edifice host rock has attendant implications for the structural stability of the edifice and the efficiency of the sidewall outgassing of the volcanic conduit. In this contribution, we present a syst...