Novel Pluronic/heparin composite nanocapsules that exhibit a thermally responsible swelling and deswelling behavior were synthesized. Pluronic F-127 preactivated with p-nitrophenyl chloroformate at its two terminal hydroxyl groups was dissolved in a methylene chloride phase. The organic phase was dispersed in an aqueous phase containing heparin. At an organic/aqueous interface, Pluronic-cross-linked heparin nanocapsules were produced. They exhibited a 1000-fold volume transition (ca. 336 nm at 25 degrees C; ca. 32 nm at 37 degrees C), and a reversible swelling and deswelling behavior when the temperature was cycled between 20 and 37 degrees C. The reversible volume transition of Pluronic nanocapsules was caused by micellization and demicellization of cross-linked Pluronic polymer chains within the nanocapsule structure in response to temperature. The morphological characters were investigated with transmission electron microscopy and small angle neutron scattering. Pluronic/heparin nanocapsules had an aqueous fluid-filled hollow interior with a surrounding shell layer below the critical temperature, but they became a collapsed core/shell structure similar to that of Pluronic micelles above it.

Pt NPs were in situ synthesised on poly(sodium styrene sulfonate) functionalized graphene supports (PSS-G) in aqueous solution. We investigate the reduction of graphene oxide, PSS adsorption on reduced graphene, and Pt NP functionalization by X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure studies (XAFS), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy and transmission electron microscopy. The as-prepared Pt on PSS-G sample (Pt-PSS-G) was used directly as a catalyst ink without further treatment. The use of PSS as a stabilizer prevents stacking of reduced graphene sheets, binds Pt NPs, and promotes mass transport of reaction species. The as-prepared Pt-PSS-G exhibits higher activity and stability for methanol oxidation reaction than Pt NPs supported on pristine graphene sheets (Pt-G). The higher activity is due to the presence of Pt NPs on the surface of the PSS-G support, which provides an integrated electron and mass transport pathway for every Pt NP. This work realizes both scalable and greener production of highly efficient catalysts, and would be valuable for practical applications of graphene based fuel cell catalysts.

This work presents formic acid oxidation on Pt deposits on Au nanoparticles dispersed on Vulcan XC-72R. The Pt deposits were produced using spontaneous deposition method contacting the Au nanoparticles with solutions containing Pt complex ions in various concentrations. The Pt deposits were characterized using CO stripping coulometry, X-ray photoelectron spectroscopy, and inductively coupled plasma atomic emission spectroscopy. When the Pt concentration is 10(-5)-10(-4) M, the Pt deposits are nanoislands of monatomic height. In the concentration range of 10(-4)-10(-3) M, the Pt deposits are most likely two-layer-thick nanofeatures. As Pt concentration increases further, the deposits become wider and thicker. Voltammetric behavior of Pt deposits reveals that on Pt deposits, dehydrogenation path is activated at the expense of poison-forming dehydration path. Furthermore, chronoamperometric measurement of the catalytic activity of Pt deposits supports that the two-layer-thick Pt deposits are most efficient in formic acid oxidation among the studied Pt deposits on Au nanoparticles. The enhancement factor of the particular Pt deposits is 2 in terms of turnover frequency, compared with a commercial Pt catalyst. Details are discussed in conjunction with Pt deposits on Au(111).

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The water leakage in an underground space cannot easily be repaired owing to the characteristics of the underground space, which not only causes continuous inconvenience to the apartment residents but also facilitates condensation. Thus, the effects of different waterproofing methods in underground spaces on changes in temperature and humidity should be quantitatively studied to establish strong measures for the condensation issue. In this study, two types of specimens were produced separately by dividing the waterproofing materials applied to underground structures into exterior and interior waterproofing construction methods; thereafter, changes in the temperature and humidity inside the specimens were observed. The test results of the evaluation regarding condensation in underground structures indicated that when exterior waterproofing materials are applied, thermal insulation maintains a steady interior temperature and keeps the humidity at an appropriate level, thereby preventing the creation of an environment conducive to the occurrence of condensation.

Mn 3 O 4 /multi-walled carbon nanotube (MWCNT) composites are prepared by chemically synthesizing Mn 3 O 4 nanoparticles on a MWCNT film at room temperature. Structural and morphological characterization has been carried out using X-ray diffraction (XRD) and scanning and transmission electron microscopies (SEM and TEM). These reveal that polycrystalline Mn 3 O 4 nanoparticles, with sizes of about 10-20 nm, aggregate to form larger nanoparticles (50-200 nm), and the Mn 3 O 4 nanoparticles are attached inhomogeneously on MWCNTs. The electrochemical behavior of the composites is analyzed by cyclic voltammetry experiment. The Mn 3 O 4 / MWCNT composite exhibits a specific capacitance of 257 Fg −1 at a scan rate of 5 mVs, which is about 3.5 times higher than that of the pure Mn 3 O 4 . Cycle-life tests show that the specific capacitance of the Mn 3 O 4 / MWCNT composite is stable up to 1000 cycles with about 85% capacitance retention, which is better than the pure Mn 3 O 4 electrode. The improved supercapacitive performance of the Mn 3 O 4 /MWCNT composite electrode can be attributed to the synergistic effects of the Mn 3 O 4 nanoparticles and the MWCNTs, which arises not only from the combination of pseudocapacitance from Mn 3 O 4 nanoparticles and electric double layer capacitance from the MWCNTs but also from the increased surface area, pore volume and conducting property of the MWCNT network.

The composites and thin films comprising individual single-walled carbon nanotubes with a polymer coating (p-cnts) have been prepared and their electromagnetic responses have been studied in a wide range from low-frequency (25-10 7 Hz) up to the infrared region. In spite of the high volume fraction of the nanotubes (up to 3.3%), the polymer coating prevents direct p-CNT contacts and the formation of the percolation network in those composites, so that p-CNTs interact only via the electromagnetic coupling. thereby it is an ideal model system to verify experimentally the fundamental issues related to carbon nanotube electromagnetics, such as the influence of inter-tube electron tunneling on the localized plasmon resonance in the terahertz range, or the infrared absorption enhancement of polymer molecules attached to the nanotube surface. Along with addressing the fundamentals, applied carbon nanotube electromagnetics got insights important for the applications of p-cnt based composites as dielectric media in the terahertz regime. In particular, we found that the real part of the permittivity of the p-CNT film in the terahertz range is rather competitive, i.e. 8-13, however the loss tangent is not so small (0.4-0.6) as has been predicted. The way to increase p-CNT terahertz performance is also discussed. Among carbon nanoparticles, metallic single-walled carbon nanotubes (CNTs) have a huge aspect ratio (10 2-10 7) and high conductivity that both provide their strong interaction with the electromagnetic and optical radiations 1-4. The high kinetic inductance of a single-walled CNT causes the slowed-down surface wave propagation along the tube in the range of the intraband electron transitions (<40 THz) 5,6. The excitation of the standing surface waves by a plane wave manifests itself as antenna resonances in the polarizability spectrum of an individual finite-length CNT 3. The first antenna resonance also called as localized plasmon resonance (LPR) appears as a broad terahertz peak in the conductivity spectra of the CNT films 7-9. The scattering theory has been developed for individual and bundled CNTs 3,10 , curved CNT 11 , CNT with a mesoscopic insertion 12 and dielectric coating 13. The electromagnetic response of a CNT composite has been theoretically described from radio-frequency up to the visible range with the Waterman-Truell approach 8 that is valid for non-interacting inclusions, i.e. when the electromagnetic interaction and electron tunneling coupling between the tubes are small. However, theoretical study of the mutual impedance between two carbon nanotubes 14,15 in radiofrequency and microwave ranges shows that the electromagnetic interaction between CNTs is essential if the distance between them is less than 0.02λ 15 (λ is a wavelength of the electromagnetic wave in the surrounding

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