http://experimentationlab.berkeley.edu/sites/default/files/AFMImages/butt_AFM.pdf

Force measurements with the atomic force microscope: Technique, interpretation and applications

Membranes have an increasingly important role in alleviating water scarcity and the pollution of aquatic environments. Promising molecular-level design approaches are reviewed for membrane materials, focusing on how these materials address the urgent requirements of water treatment applications.

Materials for next-generation desalination and water purification membranes

Structure and nanostructure in ionic liquids.

http://sealight.persiangig.com/document/1.pdf

Use of iron oxide nanomaterials in wastewater treatment: a review.

We developed two-step solution-phase reactions to form hybrid materials of Mn3O4 nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. Mn3O4 nanoparticles grown selectively on RGO sheets over free particle growth in solution allowed for the electrically insulating Mn3O4 nanoparticles wired up to a current collector through the underlying conducting graphene network. The Mn3O4 nanoparticles formed on RGO show a high specific capacity up to ~900mAh/g near its theoretical capacity with good rate capability and cycling stability, owing to the intimate interactions between the graphene substrates and the Mn3O4 nanoparticles grown atop. The Mn3O4/RGO hybrid could be a promising candidate material for high-capacity, low-cost, and environmentally friendly anode for lithium ion batteries. Our growth-on-graphene approach should offer a new technique for design and synthesis of battery electrodes based on highly insulating materials.

Mn3O4-Graphene Hybrid as a High Capacity Anode Material for Lithium Ion Batteries

This paper examines the adsorption of Pb(II) and a natural organic macromolecular compound (humic acid, HA) on polyacrylamide (PAAM) -grafted multiwalled carbon nanotubes (denoted as MWCNTs/PAAM), prepared by an N(2)-plasma-induced grafting technique. The mutual effects of HA/Pb(II) on Pb(II) and HA adsorption on MWCNTs/PAAM, as well as the effects of pH, ionic strength, HA/Pb(II) concentrations, and the addition sequences of HA/Pb(II) were investigated. The results indicated that Pb(II) and HA adsorption were strongly dependent on pH and ionic strength. The presence of HA led to a strong increase in Pb(II) adsorption at low pH and a decrease at high pH, whereas the presence of Pb(II) led to an increase in HA adsorption. The adsorbed HA contributed to modification of adsorbent surface properties and partial complexation of Pb(II) with the adsorbed HA. Different effects of HA/Pb(II) concentrations and addition sequences on Pb(II) and HA adsorption were observed, indicating different adsorption mechanisms. After adsorption of HA on MWCNTs/PAAM, the adsorption capacity for Pb(II) was enhanced at pH 5.0; the adsorption capacity for HA was also enhanced after Pb(II) adsorption on MWCNTs/PAAM. These results are important for estimating and optimizing the removal of metal ions and organic substances by use of MWCNT/PAAM composites.

Mutual effects of Pb(II) and humic acid adsorption on multiwalled carbon nanotubes/polyacrylamide composites from aqueous solutions.

Gas bubbles of nanometer size were produced on atomically flat solid surfaces and imaged by atomic force microscopy (AFM) in tapping mode in water. In AFM images, nanobubbles appeared like blight spheres. Some of the bubbles remained stable for hours during the experiments. The bubbles were disturbed under high load during AFM imaging. A related mechanism is discussed. (C) 2000 American Vacuum Society. [S0734-211X(00)02505-1].

Nanobubbles on solid surface imaged by atomic force microscopy

Since the first description in 1989 of CD4-Fc-fusion antagonists that inhibit human immune deficiency virus entry into T cells, Fc-fusion proteins have been intensely investigated for their effectiveness to curb a range of pathologies, with several notable recent successes coming to market. These promising outcomes have stimulated the development of novel approaches to improve their efficacy and safety, while also broadening their clinical remit to other uses such as vaccines and intravenous immunoglobulin therapy. This increased attention has also led to non-clinical applications of Fc-fusions, such as affinity reagents in microarray devices. Here we discuss recent results and more generally applicable strategies to improve Fc-fusion proteins for each application, with particular attention to the newer, less charted areas.

/pdf/fc-fusion-proteins-new-developments-and-future-perspectives-4561f5yjlm.pdf

Fc‐fusion proteins: new developments and future perspectives

A magnetite/graphene oxide (M/GO) composite was synthesized via a chemical reaction with a magnetite particle size of 10–15 nm and was developed for the removal of heavy metal ions from aqueous solutions. The composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The sorption of Co(II) on the M/GO composite was carried out under various conditions, that is, contact time, sorbent content, pH, ionic strength, foreign ions, and temperature. The sorption isotherms of Co(II) on the M/GO composite could be described well by the Langmuir model. The thermodynamic parameters (ΔH0, ΔS0, and ΔG0) calculated from the temperature-dependent isotherms indicated that the sorption reaction of Co(II) on the M/GO composite was an endothermic and spontaneous process. M/GO can be separated and recovered by magnetic separation. Results show that the magnetic M/GO composite is a promising sorbent material for the preconcentration an...

Synthesis of Magnetite/Graphene Oxide Composite and Application for Cobalt(II) Removal

Graphene oxide nanosheets have attracted multidisciplinary attention due to their unique physicochemical properties. Herein, few-layered graphene oxide nanosheets were synthesized from graphite using a modified Hummers method and were characterized by TEM, AFM, Raman spectroscopy, XPS, FTIR spectroscopy, TG–DTA and acid–base titrations. The prepared few-layered graphene oxide nanosheets were used as adsorbents for the preconcentration of U(VI) ions from large volumes of aqueous solutions as a function of pH, ionic strength and temperature. The sorption of U(VI) ions on the graphene oxide nanosheets was strongly dependent on pH and independent of the ionic strength, indicating that the sorption was mainly dominated by inner-sphere surface complexation rather than by outer-sphere surface complexation or ion exchange. The abundant oxygen-containing functional groups on the surfaces of the graphene oxide nanosheets played an important role in U(VI) sorption. The sorption of U(VI) on graphene oxide nanosheets increased with an increase in temperature and the thermodynamic parameters calculated from the temperature-dependent sorption isotherms suggested that the sorption of U(VI) on graphene oxide nanosheets was an endothermic and spontaneous process. The maximum sorption capacities (Qmax) of U(VI) at pH 5.0 ± 0.1 and T = 20 °C was 97.5 mg g−1, which was much higher than any of the currently reported nanomaterials. The graphene oxide nanosheets may be suitable materials for the removal and preconcentration of U(VI) ions from large volumes of aqueous solutions, for example, U(VI) polluted wastewater, if they can be synthesized in a cost-effective manner on a large scale in the future.

Jun Hu

Papers

Mutual effects of Pb(II) and humic acid adsorption on multiwalled carbon nanotubes/polyacrylamide composites from aqueous solutions.

Nanobubbles on solid surface imaged by atomic force microscopy

Fc‐fusion proteins: new developments and future perspectives

Synthesis of Magnetite/Graphene Oxide Composite and Application for Cobalt(II) Removal

Preconcentration of U(VI) ions on few-layered graphene oxide nanosheets from aqueous solutions