Investigation of hybrid ion-exchange membranes reinforced with non-woven metal meshes for electro-dialysis applications

Salt and solvent permeations across ion-exchange membranes used in electro-dialysis are directly related to the membrane material structure and chemistry. Although primarily used for aqueous effluents desalination, electro-dialysis was recently shown to be a promising technology for industrial wastewater and co-solvent mixtures purification. The harsh working conditions imposed by these liquid effluents, including high suspended solids, require the development of more chemically and mechanically resistant membranes. In this study, commercial porous stainless steel media filters (240 μm thick) were used as a backbone to prepare hybrid ion-exchange membranes by casting ion-exchange materials within the porous metal structure. The surface of the metal reinforcements was modified by plasma treatment prior to sol-gel silane grafting to improve the interface between the metal and the ion-exchange resins. The morphology of novel hybrid materials and the interface between the metal fibers and the ion-exchange material have been characterized using techniques such as scanning electron microscopy and FTIR mapping. The thickness of the silane coating was found to lie between 1 and 2 μm while water contact angle tests performed on membrane surfaces and corrosion test behaviors revealed the formation of a thin passivating oxide layer on the material surfaces providing anchoring for the silane grafting and adequate surface energy for the proper incorporation of the ion-exchange material. The hybrid membranes desalination performance were then tested in a bench top electro-dialysis cell over a range of flow rate, current densities and salt concentration conditions to evaluate the ability of the novel hybrid materials to desalinate model streams. The performance of the hybrid membranes were benchmarked and critically compared against commercially available membranes (Selemion™). Although the salt transfer kinetics across the hybrid ion-exchange composite membranes were shown to be comparable to that of the commercial membranes, the low porosity of the stainless steel reinforcements, around 60%, was shown to impede absolute salt permeations. The hybrid ion-exchange membranes were however found to be competitive at low current density and low flow velocity desalination conditions.

Investigation of hybrid ion-exchange membranes reinforced with non-woven metal meshes for electro-dialysis applications

Salt and solvent permeations across ion-exchange membranes used in electro-dialysis are directly related to the membrane material structure and chemistry. Although primarily used for aqueous effluents desalination, electro-dialysis was recently shown to be a promising technology for industrial wastewater and co-solvent mixtures purification. The harsh working conditions imposed by these liquid effluents, including high suspended solids, require the development of more chemically and mechanically resistant membranes. In this study, commercial porous stainless steel media filters (240. μm thick) were used as a backbone to prepare hybrid ion-exchange membranes by casting ion-exchange materials within the porous metal structure. The surface of the metal reinforcements was modified by plasma treatment prior to sol-gel silane grafting to improve the interface between the metal and the ion-exchange resins. The morphology of novel hybrid materials and the interface between the metal fibers and the ion-exchange material have been characterized using techniques such as scanning electron microscopy and FTIR mapping. The thickness of the silane coating was found to lie between 1 and 2. μm while water contact angle tests performed on membrane surfaces and corrosion test behaviors revealed the formation of a thin passivating oxide layer on the material surfaces providing anchoring for the silane grafting and adequate surface energy for the proper incorporation of the ion-exchange material. The hybrid membranes desalination performance were then tested in a bench top electro-dialysis cell over a range of flow rate, current densities and salt concentration conditions to evaluate the ability of the novel hybrid materials to desalinate model streams. The performance of the hybrid membranes were benchmarked and critically compared against commercially available membranes (Selemion™). Although the salt transfer kinetics across the hybrid ion-exchange composite membranes were shown to be comparable to that of the commercial membranes, the low porosity of the stainless steel reinforcements, around 60%, was shown to impede absolute salt permeations. The hybrid ion-exchange membranes were however found to be competitive at low current density and low flow velocity desalination conditions.

Controlling shareholder, expropriations and firm’s leverage decision: Evidence from Chinese Non-tradable share reform

This paper examines the effect of excess control rights on the leverage decisions made by Chinese non-SOEs before and after the Non-tradable share reform (NTS reform). We find that firms with excess control rights have more excess leverage and their controlling shareholders use the resources for tunneling rather than investing in positive NPV projects. We also find that excess leverage in firms with excess control rights decreases and the market reaction to announcements of related party transactions are more positive after NTS reform. This confirms that tunneling by the controlling shareholders actually reduced. We argue that in emerging markets where legal protection for creditors and shareholders is weak, controlling shareholders borrow excess debt to tunnel through inter-corporate loans and related party transactions. Furthermore the privatization of these economies can reduce the controlling shareholders' tunneling activities and associated excess leverage which destroys firm value.

Can international human rights law accommodate bodily diversity?

This article considers recent efforts by international bodies and advocacy groups to secure the human rights of individuals with intersex variation. Identifying that these efforts are constrained by powerful assumptions about binary sex, it argues that international rights discourse looks set to regulate intersex individuals by the same protective strategies applied to the last four decades of the women's rights movement. A frank reading of legal feminist scholarship indicates several possible risks for the nascent intersex campaign. Efforts to ensure the substantive enjoyment of rights (for all) need to move beyond the constraints of a binary system in which women and sexed/sexual minorities will always be produced as other. Having argued that human rights are not contingent on biological determinants, the right to non-discrimination on the basis of sex traits is considered.

Anisotropy for metals in non-associated flow plasticity

 A constitutive model based on Non-Associated Flow rule is implemented numerically and is shown to be capable of accurate predictions of anisotropy driven phenomena, observed during the forming processes of thin sheet metals, in a more efficient manner than other traditional approaches based on Associated Flow Rule.

Financial integration: the role of tradable and non-tradable goods

This paper examines the potential benefits of financial integration focusing on the role of tradable and non-tradable goods. We construct a new country-level index for tradability of output using disaggregate sector level data on output, imports and exports. Cross-country regressions show that for the overall sample, there is a weak positive interaction of tradibility of output and financial integration. When we focus on those countries within a middle range of institutional development, and thus within the middle range of income per capita, for these countries, the experience of integration is tempered significantly by increasing tradability of output. Sector-level regressions confirm the negative and significant interaction of trade and financial integration for this sample of countries.

Assessment of human kinematic performance with non-contact measurements for tele-rehabilitation

 Aging of population is challenging the traditional rehabilitation services for various movement disorders. In the foreseeable future, tele-rehabilitation will be a contributive factor for the well-being of the older generation. This research has tackled a series of problems in developing an automated assessment tool for human kinematic performance in tele-rehabilitation with optoelectronic bio-kinematic motion capture devices and preliminarily confirmed its applicability.