Preparation and Characterization of Graphene Oxide / Cellulose Triacetate Forward Osmosis Membranes

Forward osmosis (FO) is an emerging membrane separation technology in environmental and industrial process. This paper presents cellulose triacetate (CTA) membrane containing graphene oxide (GO) nanosheets via blending to enhance membrane performance in forward osmosis (FO) process. GO nanosheets with various loading were added into the casting solution to prepare the modified FO membranes. The prepared membranes were characterized by morphology analysis and permeability measurement. The result showed that the GO nanosheets effectively improved the performance of the CTA membranes. The CTA-0.2GO membrane had the highest water flux, reached 1.5 times as high as that of CTA membrane

Preparation and Characterization of Graphene Oxide / Cellulose Triacetate Forward Osmosis Membranes

Forward osmosis (FO) is an emerging membrane separation technology in environmental and industrial process. This paper presents cellulose triacetate (CTA) membrane containing graphene oxide (GO) nanosheets via blending to enhance membrane performance in forward osmosis (FO) process. GO nanosheets with various loading were added into the casting solution to prepare the modified FO membranes. The prepared membranes were characterized by morphology analysis and permeability measurement. The result showed that the GO nanosheets effectively improved the performance of the CTA membranes. The CTA-0.2GO membrane had the highest water flux, reached 1.5 times as high as that of CTA membrane

Conductive Cotton Filters for Affordable and Efficient Water Purification

It is highly desirable to develop affordable, energy-saving, and highly-effective technologies to alleviate the current water crisis. In this work, we reported a low-cost electrochemical filtration device composing of a conductive cotton filter anode and a Ti foil cathode. The device was operated by gravity feed. The conductive cotton filter anodes were fabricated by a facile dying method to incorporate carbon nanotubes (CNTs) as fillers. The CNTs could serve as adsorbents for pollutants adsorption, as electrocatalysts for pollutants electrooxidation, and as conductive additives to render the cotton filters highly conductive. Cellulose-based cotton could serve as low-cost support to ‘host’ these CNTs. Upon application of external potential, the developed filtration device could not only achieve physically adsorption of organic compounds, but also chemically oxide these compounds on site. Three model organic compounds were employed to evaluate the oxidative capability of the device, i.e., ferrocyanide (a model single-electron-transfer electron donor), methyl orange (MO, a common recalcitrant azo-dye found in aqueous environments), and antibiotic tetracycline (TC, a common antibiotic released from the wastewater treatment plants). The devices exhibited a maximum electrooxidation flux of 0.37 mol/h/m2 for 5.0 mmol/L ferrocyanide, of 0.26 mol/h/m2 for 0.06 mmol/L MO, and of 0.9 mol/h/m2 for 0.2 mmol/L TC under given experimental conditions. The effects of several key operational parameters (e.g., total cell potential, CNT amount, and compound concentration) on the device performance were also studied. This study could shed some light on the good design of effective and affordable water purification devices for point-of-use applications

A ZFYVE21-Rubicon-RNF34 signaling complex promotes endosome-associated inflammasome activity in endothelial cells

Abstract Internalization of complement membrane attack complexes (MACs) assembles NLRP3 inflammasomes in endothelial cells (EC) and promotes IL-β-mediated tissue inflammation. Informed by proteomics analyses of FACS-sorted inflammasomes, we identify a protein complex modulating inflammasome activity on endosomes. ZFVYE21, a Rab5 effector, partners with Rubicon and RNF34, forming a “ZRR” complex that is stabilized in a Rab5- and ZFYVE21-dependent manner on early endosomes. There, Rubicon competitively disrupts inhibitory associations between caspase-1 and its pseudosubstrate, Flightless I (FliI), while RNF34 ubiquitinylates and degradatively removes FliI from the signaling endosome. The concerted actions of the ZRR complex increase pools of endosome-associated caspase-1 available for activation. The ZRR complex is assembled in human tissues, its associated signaling responses occur in three mouse models in vivo, and the ZRR complex promotes inflammation in a skin model of chronic rejection. The ZRR signaling complex reflects a potential therapeutic target for attenuating inflammasome-mediated tissue injury