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An accurate estimation of a casualty rate is critical in response to earthquake disasters, and could allow an increase in the survival rate. Building damage is considered to be a major cause of earthquake casualties in developing countries. High-resolution satellite imagery (HRSI) can be used to detect the building damage in a period of a short time. This makes it possible to use a model to estimate earthquake casualties immediately after the occurrence of an earthquake. With respect to the capability of HRSI, this study built a new model for estimating the casualty rate in an earthquake disaster based on remote sensing and a geographical information system. Three groups of earthquake data, the 2003 Bam earthquake, the 2008 Wenchuan earthquake, and the 2010 Yushu earthquake, were used to evaluate this model. The results indicated that our new model significantly improved the accuracy in predicting the casualty rate. The parameters used in the model vary between developed and developing countries. This study could provide valuable information for a more efficient rescue operation in response to earthquakes.

A new UV-reactive monomer piperazine-N,N'-bis(acryloxyethylaryl-phosphoramidate) (N-PBAAP) containing phosphorus and nitrogen was synthesized and used as flame retardant for an ether-type UV-cured polyurethane acrylate (PUA) coating. The thermal properties of the PUA films were investigated by thermogravimetric analysis (TGA) in air and nitrogen atmosphere. The TGA results showed that the incorporation of N-PBAAP can obviously enhance the char residue of the PUA coatings. From the TGA and real time Fourier transformed infrared spectroscopy (RT-FTIR) results, different degradation behaviors were observed in the PUA coatings with different N-PBAAP content. The combustibility of the PUA coatings was evaluated by microscale combustion calorimeter (MCC). The MCC results revealed that the addition of N- PBAAP in the coatings can significantly reduce the peak Heat Release Rate (pHRR), Heat Release Capacity (HRC) and the Total Heat Release (THR) of the samples. Furthermore, dynamical mechanical thermal analysis (DMA) was employed to examine the viscoelastic properties of the PUA films. It was found that the incorporation of N-PBAAP in the formulation can bring in more functional groups to the coatings, which results in an increase of the glass transition temperature (Tg) and cross linking density (XLD) of the films.

The first plasma discharges were successfully achieved on the experimental advanced superconducting tokamak (EAST) in 2006. The sawteeth behaviours were observed by means of soft x-ray diagnostics and ECE signals in the EAST. The displacement and radius of the q = 1 surface was studied and compared with the result of equilibrium calculation. The density sawtooth oscillation was also observed by the HCN laser interferometer diagnostics. The structure of the EAST operational region was studied in detail. Plasma performance was obviously improved by the boronization and wall conditioning. It was observed that lower qa and a wider stable operating region is extended by the GDC boronization.

Aims To investigate the contribution of regulatory T cells and co-stimulatory molecules in CD4+ T cells to the development of Type 1 diabetes (T1D). Methods Twelve patients with T1D, nine patients with systemic lupus erythematosus (SLE), and 12 age-matched healthy control subjects participated. We analysed the proportions of CD25+CD4+ T cells and natural killer T cells (NKT cells), and the expression levels of Foxp3, CTLA-4, CD28, ICOS, PD-1 and BTLA in peripheral blood mononuclear cells and purified CD4+ T cells. Results There were no significant differences in the proportions of CD25+ CD4+ T cells or NKT cells among the three groups. PD-1 expression levels of peripheral CD4+ T cells from T1D patients were significantly lower than those from healthy control subjects (P = 0.00066). In contrast, PD-1 expression levels were similar in SLE patients and healthy control subjects. The expression levels of Foxp3, CTLA-4, CD28, ICOS and BTLA were similar in the three groups. Conclusions Decreased expression of the PD-1 gene in CD4+ T cells may contribute to the development and/or maintenance of autoimmune T1D. As the population studied was small and heterogeneous, further studies are required to confirm the findings.

This paper describes a CW submillimeter waveguide discharge‐pumped DCN laser operating on 190 and 195μm lines with novel mixture gas(N2, CD4, and D2). No brown polymer deposit was found after long time discharge even at low wall temperature. The laser discharge length is 3 m, and the resonator length is 3.4 m. The resonator cavity consists of a pyrex tube of 54 mm diameter and two plane reflectors against its ends, one is a plane mirror, the other is a metal mesh. After optimization of various parameters, such as the N2:CD4:D2 gas mixture, the discharge current and the wall temperature, this laser delivers 150 and 160mW on the 190 and 195μm lines, respectively, for EH11 mode.

A successful experiment on lower hybrid wave (LHW) and ion Bernstein wave (IBW) synergy has been carried out in the HT-7 superconducting tokamak. With 560KW of LHW heating power and 160 KW of IBW heating power, during the synergy of the LHW and IBW experiment we achieved an improved plasma: the electron density increased and peaked, the soft X intensity increased too. A five-channel far-infrared (FIR) hydrogen cyanide (HCN) laser interferometer was used to measure the electron density profile. The particle diffusion coefficient was studied for the experiment, and the result compared with the heat diffusion coefficient. With the same injected LHW and IBW power, high electron density ne can deduce the electron pulse propagation and the particle diffusion.

In this paper the lasing modes and the propagation property of a CW DCN laser, which cavity is a 50 mm inner diameter with length of 3.4 m, were studied. The modes of 195 and 190 μm lines are well identified by the micrometer mount of the movable mirror in one end of the cavity. The beam profile is found to be qualitatively Gaussian in the far-field (Z > 4 m).

A high power CW 195 μm DCN laser has been developed for fusion plasma diagnostics. Optimization of various parameters (such as the rate of N2:CD4:He gas mixture, the gas pressure and the discharge current, the wall temperature and the output couple) for maximum output power at the DCN laser were performed and reported in this paper. Output power of about 220 mW on the 195 μm line has been obtained with 3.4 m long and 54 mm inner diameter discharge-pumped wave-guide laser. A new mixture gas of N2:CD4:D2 was used in producing a stable high-power discharge and preventing the deposition of brown polymer with lower wall temperature and discharge current.

Ge nanocrystals (nc-Ge) embedded in silicon oxide thin films have been fabricated using rf magnetron co-sputtering deposition and post-growth thermal annealing method. Raman scattering and photoluminscence (PL) measurements have been used to characterize their crystallization and light emission properties. The Ge crystallinity and nanocrystal size obtained using a three-peak fitting method based on a phonon confinement model have been found to increase with the increase of annealing temperature. The observed blue photoluminescence band located at ∼3.1 eV and a weaker band at ∼2.4 eV under the excitation of 325 nm laser did not show significant size dependence while their relative intensities were related to the addition of H 2 or O 2 into the sputtering ambient. The photoluminescence mechanism is discussed.

This paper describes a CW sub-millimeter waveguide dischargepumped DCN laser operating on 190 and 195 mu m lines. The laser discharge length is 3 m, and the resonator length is 3.4 m. The resonator cavity consists of a pyrex tube of 54 mm diameter and two plane reflectors against its ends, one is a plane mirror, the other is a metal mesh. After optimization of various parameters, such as the N2:CD4:He gas mixture, the pressure and the discharge current, the wall temperature and the output couple, this laser delivers 200 and 220mW on the 190 and 195 mu m lines, respectively, for EH11 mode.

We report an investigation of third-order optical nonlinearities in Ge nanocrystals (∼6 nm radius) embedded in silica matrix using the Z-scan and pump-probe techniques with femtosecond laser pulses at 780-nm wavelength. The nanocrystallite Ge samples were prepared using magnetron co-sputtering and post-thermal annealing at 800 °C. The nonlinear absorption coefficient and refractive index of the Ge nanocrystals were determined to be in the range from 1.8×10-7 to 6.8×10-7 cm/W and 1.5×10-12 to 8.0×10-12 cm2/W, respectively, which are proportional to the Ge atomic fraction in the matrix. Relaxation of the nonlinear response was found to have two characteristic time constants, 1.8 ps and 65 ps. The mechanisms responsible for the observed nonlinear response are discussed.

The density profiles were measured in the Hefei tokamak-7 (HT-7) [World Survey of Activities in Controlled Fusion Research, Nuclear Fusion Special Supplement (International Atomic Energy Agency, Vienna, 1997), p. 61] ohmic discharges by means of a new multichannel far-infrared (FIR) laser interferometer. The progress on the extension of the HT-7 ohmic discharge operation region was introduced. The experiment results at the density limit, the multifaceted asymmetric radiation from the edge (MARFE) phenomena, the rf (radio frequency) boronization experiments, and the fueling efficiency studies were reported. The plasma physics in the molecular beam injection (MBI), the pellet injection (PI), and the gas puffing (GP) fueling experiments was studied and discussed.

Zinc oxide thin films have been grown on silicon (100) and sapphire (0001) substrates by pulsed laser deposition. The thin films deposited at different processing parameters were evaluated by x-ray diffraction, Raman spectroscopy, and atomic force microscopy (AFM). The influences of substrate temperature and laser fluence on the properties of the deposited thin films were studied. The full width at half maximum of (0002) x-ray diffraction lines of the films deposited on silicon and sapphire substrates reach a value as small as 0.25° and 0.18°, respectively. The relationship between the intensities of the peaks at 438 and 579 cm−1 in ZnO Raman spectra and deposition temperature were also investigated. Average roughness and surface morphology of the ZnO thin films deposited on Si substrates were evaluated by AFM.

Germanium nanocrystals immersed in amorphous SiO x matrix have been synthesized by r.f. co-sputter deposition of Ge and quartz with post-growth annealing at 600-900 °C. The structures of the Ge nanocrystals and SiO x matrix have been studied with x-ray diffraction, high-resolution transmission electron microscopy and XPS depth profiling. Broad-band photoluminescence spectra have been observed from samples annealed at temperatures higher than 600°C. Possible photoluminescence mechanisms have also been discussed.

Spherical Ge nanocrystals well-dispersed in amorphous silicon oxide matrix have been synthesized with different sizes, and significant size-dependent Raman shift and broadening have been observed. The lattice constant of Ge nanocrystals well-bonded to silicon oxide matrix has been characterized nearly size-independent. With our proposed stress generation and relaxation mechanisms, stress effects in our samples have been analyzed to be insignificant with respect to phonon confinement effects. The phenomenological model introduced by [Richter, Wang, and Ley, Solid State Commun. 39, 625 (1981] with Gaussian weighting function and TO2 phonon dispersion function has been found to give a quite good description of the measured size-dependence of Raman shift and broadening. A 3-peak fitting method has been proposed to determine Ge nanocrystal size and film crystallinity. After physically quantizing quantum-confined one-dimensional elastic waves, we have deduced that each quantum-confined phonon possesses an insta...

Polycrystalline silicon germanium (Si1−xGex) films deposited by the rf sputtering technique were characterized using a combination of transmission electron microscopy (TEM), atomic force microscopy (AFM), x-ray diffraction (XRD), and Raman spectroscopy techniques. The TEM results showed small grains (10–20 nm) with microtwins, and AFM showed islands of 100–200 nm in the films. The XRD results show that our films consist of Si1−xGex alloy with no cluster of Ge or a Ge-rich material embedded in a Si matrix. The smaller grains in our films could be a result of an abundance of nucleating sites or impurities in the films. Raman spectroscopy results indicate that our films were strain free.