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Based on a field monitored dataset measured at landfill #1 over 21 years, the characteristics of settlement coupling mechanical creep and biodegradation and the residual settlement were analyzed. Since landfill #1 is a multi-stage municipal solid waste (MSW) landfill where dykes are constructed after landfilling for subsequent waste fills, the waste decomposition between the lower and upper lifts was quite different and it is difficult to discern between the mechanical creep and bio-compression on the settlement curves. The compression ratio coupled with mechanical creep and bio-compression and the residual compression ratio were determined as 0.233 and 0.068, respectively. This implies that biodegradation was gradually and significantly reduced in the MSW settlement behavior after the residual settlement began. The starting date of residual settlement was distributed between 3821 and 5402 days from the initial date of landfilling. The settlement coupling mechanical creep and biodegradation (SMB) was 2.9 times larger than the residual settlement (SRS), and the duration of SMB is determined to be 0.3 times that of SRS. In addition, the remnant methane gas content existed in the landfill gas, and low-level biodegradation was still generated in the waste buried for more than 10 years after the residual settlement began.

GISAXS has been used to study morphology change of $��$-Fe$_2$O$_3$ nanocubes after annealing processes. A submonolayer of the nanocubes was deposited on a Si(100) substrate. While an annealing at 400 $^\circ$C in a vacuum does not change a GISAXS pattern from as-prepared nanocubes submonolayer, annealing in the air at the same temperature altered the GISAXS pattern significantly. SEM image showed that the air-annealed nanocubes were coated with thin layers which were identified as amorphous carbon layers based on Raman measurements. GISAXS simulations from morphologies of nanocube with 38 nm side-length and core-shell (nanocube-core and 7 nm thick carbon-shell) nicely reproduced measured patterns from the vacuum annealed and the air-annealed nanocubes, respectively. The current study provides new approach for in-situ characterization of carbon deposition on a uniform shape nanoparticle through monitoring of deposited carbon thickness., 15 pages, 6 figures

Atomic structure of a mono-dispersive hematite ($��$-Fe$_2$O$_3$) nanocube $(0 1\bar1 2)$ surface was determined with synchrotron X-ray diffraction. The $��$-Fe$_2$O$_3$ nanocubes were prepared through a hydrothermal process and a single layer of nanocubes was deposited on a silicon substrate with a drop cast method. The alignment of nanocubes with their $(0 1\bar1 2)$ surfaces parallel to the substrate is confirmed with grazing incidence X-ray diffraction. Specular crystal truncation rods (CTR's) from as-prepared and vacuum annealed nanocube surfaces have been measured and they are drastically different from previously reported CTR's from macroscopic single crystal $(0 1\bar1 2)$ surfaces. The measured CTR's from nanocube surfaces are explained well with the atomic structure models of half of atoms in top Fe layer being missing while extra oxygen-layers cover the half-missing Fe layer. An acidic environment during hydrothermal nanocube synthesis process is proposed as the main cause of the difference., 18 pages, 5 figures

We report Resonant Inelastic X-ray Scattering (RIXS) study of the magnetic excitation spectrum in a highly insulating Eu$_{2}$Ir$_{2}$O$_{7}$ single crystal that exhibits a metal-insulator transition at $T_{MI}$ = 111(7) K. A propagating magnon mode with 20 meV bandwidth and 28 meV magnon gap is found in the excitation spectrum at 7 K, which is expected in the all-in-all-out (AIAO) magnetically ordered state. This magnetic excitation exhibits substantial softening as temperature is raised towards $T_{MI}$, and turns into highly damped excitation in the paramagnetic phase. Remarkably, the softening occurs throughout the whole Brillouin zone including the zone boundary. This observation is inconsistent with magnon renormalization expected in a local moment system, and indicates that the strength of electron correlation in Eu$_{2}$Ir$_{2}$O$_{7}$ is only moderate, so that electron itinerancy should be taken into account in describing its magnetism., Comment: 5 pages, 3 figures