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Lei Jiang - One of the best experts on this subject based on the ideXlab platform.

  • contact angle measurement of natural materials
    Colloids and Surfaces B: Biointerfaces, 2018
    Co-Authors: Tianyi Zhao, Lei Jiang

    Abstract Contact angle (CA) is the most important parameter used to quantify the Wettability of solid surfaces. In order to evaluate Wettability performance, numerous methods have been developed to measure the CA of solid surfaces. Recent years have seen increased focus on the special Wettability performance of various biological materials. Biomimetic Wettability has become one of the most popular research fields, and novel CA measurements have been invented accordingly. In this protocol, we introduce several CA measurement techniques mainly based on the image capture method, which is commonly to investigate the Wettability of natural materials. According to the solid/liquid/gas context, we classify CA measurements into three types: in air, under liquid, and air bubble measurements, and describe methods for each. The precise measurement of CA together with study of surface structure can reveal the mechanisms of special Wettability, thus accelerating the investigation of biomaterials.

  • bioinspired super Wettability from fundamental research to practical applications
    Angewandte Chemie, 2015
    Co-Authors: Liping Wen, Ye Tian, Lei Jiang

    Engineered Wettability is a traditional, yet key issue in surface science and attracts tremendous interest in solving large-scale practical problems. Recently, different super-Wettability systems have been discovered in both nature and experiments. In this Review we present three types of super-Wettability, including the three-dimensional, two-dimensional, and one-dimensional material surfaces. By combining different super-wettabilities, novel interfacial functional systems could be generated and integrated into devices for use in tackling current and the future problems including resources, energy, environment, and health.

  • efficient water collection on integrative bioinspired surfaces with star shaped Wettability patterns
    Advanced Materials, 2014
    Co-Authors: Hao Bai, Lei Jiang, Lin Wang, Ruize Sun, Yongmei Zheng

    Inspired by the water-collecting strategies of desert beetles and spider silk, a novel kind of surface with star-shaped wettablity patterns has been developed. By combining both Wettability and shape gradients, the as-prepared surface has gained higher efficiency in water collection compared to circle-shaped Wettability patterns and uniformly superhydrophilic or superhydrophobic surfaces.

  • Patterning of controllable surface Wettability for printing techniques
    Chemical Society Reviews, 2013
    Co-Authors: Dongliang Tian, Yanlin Song, Lei Jiang

    Patterning of controllable surface Wettability has attracted wide scientific attention due to its importance in both fundamental research and practical applications. In particular, it is crucial to form clear image areas and non-image areas in printing techniques based on wetting and dewetting. This review summarizes the recent research on and applications of patterning of controllable surface Wettability for printing techniques, with a focus on the design and fabrication of the precise surface Wettability patterning by enhancing the contrast of hydrophilicity and hydrophobicity, such as superhydrophilicity and superhydrophobicity. The selected topics mainly include patterned surface Wettability for lithographic printing with different plate-making techniques, patterned surface Wettability for microcontact printing with a patterned wetting stamp and special Wettability mediated patterning microtransfer printing, patterned surface Wettability for inkjet printing with controllable surface Wettability of the substrate and printing head to ink, and patterned surface Wettability by a combination of different printing techniques. A personal perspective on the future development and remaining challenges of this research is also briefly discussed.

  • fine control of the Wettability transition temperature of colloidal crystal films from superhydrophilic to superhydrophobic
    Advanced Functional Materials, 2007
    Co-Authors: Jingxia Wang, Yanli Song, Lei Jiang

    A facile strategy for finely controlling the Wettability transition temperature of colloidal-crystal films from superhydrophilic (water contact angle, CA, 0°) to superhydrophobic (water CA, 150.5°) is demonstrated. The colloidal-crystal films are assembled from poly(styrene-n-butyl acrylate-acrylic acid) amphiphilic latex spheres. The Wettability transition temperature of the films can be well tuned by adjusting the n-butyl acrylate/styrene balance of the latex spheres. Superhydrophobic films are achieved when assembled at 90, 80, 70, 60, 40, or even 20 °C. This approach offers the flexibility of fabricating colloidal crystals with desired and tunable Wettability, and can be further extended to general materials, opening up new perspectives in controlling the Wettability behavior by chemical composition.

Jingcheng Hao - One of the best experts on this subject based on the ideXlab platform.

  • Reversibly switchable Wettability.
    Chemical Society reviews, 2010
    Co-Authors: Bingwei Xin, Jingcheng Hao

    This critical review outlines the current state-of-the-art research on the reversibly switchable Wettability of surface brought about by external stimuli and the exchange of counterions. Chemical composition and surface topography are the two key factors in the Wettability of solid substrates. Applying external stimuli and exchanging counterions of ionic liquids and polyelectrolyte films are valuable approaches for rendering the change in surface chemistry and/or topography, and for driving the transition between hydrophilicity and hydrophobicity of surfaces. Through the combination of stimuli-responsive films and micro-/nanostructural surfaces, smart surfaces with reversible switching between superhydrophobicity and superhydrophilicity have been achieved. As an important advancement in reversibly switchable Wettability, this review briefly introduces ionic liquids (ILs) as on-off systems to obtain reversibly switchable Wettability and then discusses in more detail the methods to induce the reversibly switchable Wettability of surfaces modified by ILs, additives, or thin films. In addition to reversibly switchable Wettability mechanisms, open problems and potential solutions are discussed (157 references).

Stefan Iglauer - One of the best experts on this subject based on the ideXlab platform.

  • effect of Wettability heterogeneity and reservoir temperature on co2 storage efficiency in deep saline aquifers
    International Journal of Greenhouse Gas Control, 2018
    Co-Authors: Ahmed Barifcani, Emad A Alkhdheeawi, Stephanie Vialle, Mohammad Sarmadivaleh, Stefan Iglauer

    Abstract Reservoir heterogeneity at various length scales is a well-established fact. This includes reservoir Wettability − a key factor influencing CO2 geo-storage efficiency and containment security − which changes with depth, and is generally non-uniform due to different depositional environments and fluid flow paths over geological times. However, the effect of heterogeneous Wettability distribution on CO2 storage efficiency is not understood. Moreover, there is a knowledge gap in terms of how temperature affects capillary and dissolution trapping, CO2 mobility and vertical CO2 migration distance, particularly when coupled with Wettability heterogeneity effects. Thus, in this work we studied the effect of Wettability heterogeneity and reservoir temperature on the vertical CO2 plume migration, and capillary and dissolution trapping capacities. Our results clearly show that both Wettability heterogeneity and reservoir temperature have a significant effect on vertical CO2 migration, and the associated capillary and dissolution trapping mechanisms: both heterogeneously distributed Wettability and higher temperature significantly accelerated the vertical CO2 migration, CO2 mobility and solubility trapping, while it reduced residual trapping. We thus conclude that Wettability heterogeneity and reservoir temperature are important factors in the context of CO2 geo-storage, and that heterogeneous Wettability and higher reservoir temperatures reduce storage capacity.

  • Wettability alteration of oil-wet carbonate by silica nanofluid.
    Journal of colloid and interface science, 2015
    Co-Authors: Sarmad Al-anssari, Ahmed Barifcani, Shaobin Wang, Lebedev Maxim, Stefan Iglauer

    Changing oil-wet surfaces toward higher water Wettability is of key importance in subsurface engineering applications. This includes petroleum recovery from fractured limestone reservoirs, which are typically mixed or oil-wet, resulting in poor productivity as conventional waterflooding techniques are inefficient. A Wettability change toward more water-wet would significantly improve oil displacement efficiency, and thus productivity. Another area where such a Wettability shift would be highly beneficial is carbon geo-sequestration, where compressed CO2 is pumped underground for storage. It has recently been identified that more water-wet formations can store more CO2. We thus examined how silica based nanofluids can induce such a Wettability shift on oil-wet and mixed-wet calcite substrates. We found that silica nanoparticles have an ability to alter the Wettability of such calcite surfaces. Nanoparticle concentration and brine salinity had a significant effect on the Wettability alteration efficiency, and an optimum salinity was identified, analogous to that one found for surfactant formulations. Mechanistically, most nanoparticles irreversibly adhered to the oil-wet calcite surface (as substantiated by SEM-EDS and AFM measurements). We conclude that such nanofluid formulations can be very effective as enhanced hydrocarbon recovery agents and can potentially be used for improving the efficiency of CO2 geo-storage.

Xun Hou - One of the best experts on this subject based on the ideXlab platform.

  • femtosecond laser controlled Wettability of solid surfaces
    Soft Matter, 2015
    Co-Authors: Jiale Yong, Feng Chen, Qing Yang, Xun Hou

    Femtosecond laser microfabrication is emerging as a hot tool for controlling the Wettability of solid surfaces. This paper introduces four typical aspects of femtosecond laser induced special Wettability: superhydrophobicity, underwater superoleophobicity, anisotropic Wettability, and smart Wettability. The static properties are characterized by the contact angle measurement, while the dynamic features are investigated by the sliding behavior of a liquid droplet. Using different materials and machining methods results in different rough microstructures, patterns, and even chemistry on the solid substrates. So, various beautiful wettabilities can be realized because Wettability is mainly dependent on the surface topography and chemical composition. The distinctions of the underlying formation mechanism of these wettabilities are also described in detail.

Abdolhossein Hemmati Sarapardeh - One of the best experts on this subject based on the ideXlab platform.

  • toward mechanistic understanding of natural surfactant flooding in enhanced oil recovery processes the role of salinity surfactant concentration and rock type
    Journal of Molecular Liquids, 2016
    Co-Authors: Saeed Jafari Daghlian Sofla, Mohammad Sharifi, Abdolhossein Hemmati Sarapardeh

    Abstract Surfactant flooding has emerged as an interesting enhanced oil recovery (EOR) process due to Wettability alteration and reduction of oil-water interfacial tension (IFT). Environmental concerns and high cost, cause synthetic surfactant flooding to become expensive and uneconomical in some circumstances. Natural surfactants are environment-friendly and less expensive than synthetic surfactants which recently have been proposed as alternatives for synthetic surfactants in EOR processes. However, the exact mechanism behind natural surfactant flooding as EOR process is an unsettled and complex issue that has not been completely understood. In this communication, the use of natural surfactants as an alternative for synthetic surfactants for Wettability alteration of oil-wet rocks in EOR processes was investigated. Through the wide range of experiments, the performance of a natural surfactant named Cedar in the Wettability alteration of carbonate and sandstone rocks was deeply studied. Moreover the effect of natural surfactant on oil-water interfacial tension was compared with common used synthetic surfactants. The results showed that Cedar is very efficient in Wettability alteration of both carbonate and sandstone rocks and its effect is comparable with common used synthetic surfactants. In addition, it was found that the cationic surfactant is more effective than anionic surfactants in Wettability alteration of carbonate reservoirs. On the other hand, the anionic surfactants are very effective in sandstone rocks. In addition, two distinct trends were observed for Wettability alteration of surfactants at different salt concentrations. When the head of surfactant and rock surface carries the same charge, there is an optimum salinity for Wettability alteration. Finally, the core flooding experiments demonstrated that natural surfactant can increase oil recovery efficiently.