Three Dimensional Numerical Simulation of Polymer Flooding in Homogeneous and Heterogeneous Systems

A physically based numerical model of drifting and blowing snow in three-dimensional terrain is developed. The model includes snow transport by saltation and suspension. As an example, a numerical simulation for an Alpine ridge is presented and compared with field measurements.

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Organotrialkoxysilane-Functionalized Prussian Blue Nanoparticles-Mediated Fluorescence Sensing of Arsenic(III)

Nanomaterials ◽

10.3390/nano11051145 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1145

Author(s):

Prem. C. Pandey ◽

Shubhangi Shukla ◽

Roger J. Narayan

Keyword(s):

Prussian Blue ◽

Chemical Reduction ◽

Low Cost ◽

Three Dimensional ◽

Heterogeneous Systems ◽

Lattice Points ◽

Radiative Energy ◽

Fluorescence Sensing ◽

Emission Signal ◽

Prussian Blue Nanoparticles

Prussian blue nanoparticles (PBN) exhibit selective fluorescence quenching behavior with heavy metal ions; in addition, they possess characteristic oxidant properties both for liquid–liquid and liquid–solid interface catalysis. Here, we propose to study the detection and efficient removal of toxic arsenic(III) species by materializing these dual functions of PBN. A sophisticated PBN-sensitized fluorometric switching system for dosage-dependent detection of As3+ along with PBN-integrated SiO2 platforms as a column adsorbent for biphasic oxidation and elimination of As3+ have been developed. Colloidal PBN were obtained by a facile two-step process involving chemical reduction in the presence of 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane (EETMSi) and cyclohexanone as reducing agents, while heterogeneous systems were formulated via EETMSi, which triggered in situ growth of PBN inside the three-dimensional framework of silica gel and silica nanoparticles (SiO2). PBN-induced quenching of the emission signal was recorded with an As3+ concentration (0.05–1.6 ppm)-dependent fluorometric titration system, owing to the potential excitation window of PBN (at 480–500 nm), which ultimately restricts the radiative energy transfer. The detection limit for this arrangement is estimated around 0.025 ppm. Furthermore, the mesoporous and macroporous PBN-integrated SiO2 arrangements might act as stationary phase in chromatographic studies to significantly remove As3+. Besides physisorption, significant electron exchange between Fe3+/Fe2+ lattice points and As3+ ions enable complete conversion to less toxic As5+ ions with the repeated influx of mobile phase. PBN-integrated SiO2 matrices were successfully restored after segregating the target ions. This study indicates that PBN and PBN-integrated SiO2 platforms may enable straightforward and low-cost removal of arsenic from contaminated water.

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Three-dimensional numerical simulation of wave-induced scour around a pile on a sloping beach

Ocean Engineering ◽

10.1016/j.oceaneng.2021.109174 ◽

2021 ◽

Vol 233 ◽

pp. 109174

Author(s):

Jinzhao Li ◽

David R. Fuhrman ◽

Xuan Kong ◽

Mingxiao Xie ◽

Yilin Yang

Keyword(s):

Numerical Simulation ◽

Three Dimensional ◽

Sloping Beach ◽

Wave Induced

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Strata behavior and control strategy of backfilling collaborate with caving fully-mechanized mining

Open Geosciences ◽

10.1515/geo-2020-0168 ◽

2020 ◽

Vol 12 (1) ◽

pp. 703-717

Author(s):

Yin Wei ◽

Wang Jiaqi ◽

Bai Xiaomin ◽

Sun Wenjie ◽

Zhou Zheyuan

Keyword(s):

Numerical Simulation ◽

Control Strategy ◽

Three Dimensional ◽

Simulation Method ◽

Mine Pressure ◽

Hydraulic Support ◽

Transition Area ◽

Pressure Concentration ◽

Strata Behavior ◽

And Control

AbstractThis article analyzes the technical difficulties in full-section backfill mining and briefly introduces the technical principle and advantages of backfilling combined with caving fully mechanized mining (BCCFM). To reveal the strata behavior law of the BCCFM workface, this work establishes a three-dimensional numerical model and designs a simulation method by dynamically updating the modulus parameter of the filling body. By the analysis of numerical simulation, the following conclusions about strata behavior of the BCCFM workface were drawn. (1) The strata behavior of the BCCFM workface shows significant nonsymmetrical characteristics, and the pressure in the caving section is higher than that in the backfilling section. φ has the greatest influence on the backfilling section and the least influence on the caving section. C has a significant influence on the range of abutment pressure in the backfilling section. (2) There exits the transition area with strong mine pressure of the BCCFM workface. φ and C have significant effect on the degree of pressure concentration but little effect on the influence range of strong mine pressure in the transition area. (3) Under different conditions, the influence range of strong mine pressure is all less than 6 m. This article puts forward a control strategy of mine pressure in the transition area, which is appropriately improving the strength of the transition hydraulic support within the influence range (6 m) in the transition area according to the pressure concentration coefficient. The field measurement value of Ji15-31010 workface was consistent with numerical simulation, which verifies the reliability of control strategy of the BCCFM workface.

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