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71.
P. Godin R. Graziotti A. Damien P. Masniere 《International Journal of Hydrogen Energy》1977,2(3):291-297
Corrosion of chrysotile asbestos tissue (diaphragm material) was determined at 115–200°C in pressure vessels (1–20 bars). These tests have shown the good shape of this asbestos material for 2000/h with an unchanged solution of potash at 200°C under a 20 bars pressure, and a progressive elimination of the silica when potash solution is renewed and partial destruction of the samples. 相似文献
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A protective effect of sphingolipids on colorectal cancer (CRC) has been reported in certain mouse strains. It is unknown if sphingolipids are protective in a p53 deficiency mouse model of CRC. This study investigated the effect of sphingomyelin (SM) on intestinal sphingomyelinase (SMase) activity, colonic epithelial biology and azoxymethane (AOM)-induced CRC. Groups of wild-type (C57BL/6J) and p53+/- mice were fed 0.1% SM diet for 4 wk, administered a single AOM injection and then killed 6 h later to measure apoptosis and proliferation. Separately, both mouse types were fed 0.05% SM diet, administered three AOM injections and killed 33-38 wk later to measure tumour formation. SM significantly increased SMase activity and reduced proliferation (p < 0.05) in wild-type and p53+/- mice. SM did not regulate baseline apoptosis, apoptotic response to AOM or apoptosis in tumours, nor did it restore defective apoptosis in p53+/- mice. There was a nonsignificant trend to reduced tumour incidence with SM in wild-type (p = 0.15) and p53+/- (p = 0.12) mice. In conclusion, while increasing intestinal SMase activity and suppressing proliferation, SM did not promote any form of apoptosis and failed to achieve significant protection in these mice. Further investigation to understand the variable effect of SM in preventing CRC is warranted. 相似文献
74.
Shinko Tomoki Hénaff Gilbert Halm Damien Benoit Guillaume Bahsoun Hadi 《Metallurgical and Materials Transactions A》2020,51(8):4313-4326
Metallurgical and Materials Transactions A - Aiming to investigate the dependency of hydrogen-affected fatigue crack growth (HAFCG) on the loading frequency f, this study experimentally... 相似文献
75.
Frédéric Soulignac Pierre-Alain Danis Damien Bouffard Vincent Chanudet Etienne Dambrine Yann Guénand Tristan Harmel Bastiaan W. Ibelings Dominique Trevisan Rob Uittenbogaard Orlane Anneville 《Journal of Great Lakes research》2018,44(4):756-764
Lake biological parameters show important spatio-temporal heterogeneities. This is why explaining the spatial patchiness of phytoplankton abundance has been a recurrent ecological issue and is an essential prerequisite for objectively assessing, protecting and restoring freshwater ecosystems. The drivers of these heterogeneities can be identified by modeling their dynamics. This approach is useful for theoretical and applied limnology. In this study, a 3D hydrodynamic model of Lake Geneva (France/Switzerland) was created. It is based on the Delft3D suite software and includes the main tributary (Rhône River) and two-dimensional high-resolution meteorological forcing. It provides 3D maps of water temperature and current velocities with a 1?h time step on a 1?km horizontal grid size and with a vertical resolution of 1?m near the surface to 7?m at the bottom of the lake. The dynamics and the drivers of phytoplankton heterogeneities were assessed by combining the outputs of the model and chlorophyll-a concentration (Chl-a) data from MERIS satellite images between 2008 and 2012. Results highlight physical mechanisms responsible for the occurrence of seasonal hot-spots in phytoplankton abundance in the lake. At the beginning of spring, Chl-a heterogeneities are usually caused by an earlier onset of phytoplankton growth in the shallowest and more sheltered areas; spatial differences in the timing of phytoplankton growth can be explained by spatial variability in thermal stratification dynamics. In summer, transient and locally higher phytoplankton abundances are observed in relation to the impact of basin-scale upwelling. 相似文献
76.
Damien P. Igoe Alfio V. Parisi Abdurazaq Amar Nathan J. Downs Joanna Turner 《International journal of remote sensing》2018,39(9):2766-2783
A new method for quantifying the total ozone column (TOC) using a smartphone image sensor has been developed and validated. The TOC has been evaluated for relatively cloud free days at high air masses for solar zenith angles between 49.7° and 76.7° at a sub-tropical site. The method is based on the evaluation of the direct solar irradiances at 305 and 312 nm using the red colour pixel values of the solar disc recorded at these wavelengths by a smartphone camera. Narrow bandpass filters of 2 nm full width at half maximum at each of the two wavelengths were used in turn placed over the camera sensor to directly image the solar disc. The calibration of the pixel values of the solar disc to provide the direct solar irradiances at each of these two wavelengths allowed evaluation of the TOC calibrated to a portable sun photometer. The root mean square error (RMSE) for the smartphone-derived ozone values calibrated to corresponding values from a portable sun photometer was 4.3 Dobson Units (DU). The validation measurements for the smartphone-derived ozone values provided an average residual of 3.5% (up to a maximum of 11%) compared to the corresponding portable sun photometer values, with an RMSE of 8.4 DU during days of intermittent inclement weather conditions. The evaluation of the TOC based on a widely available device such as a smartphone has the potential to increase current citizen science initiatives valued by the general public and school-aged learners by enhancing knowledge and awareness of ozone and the resulting influences on the solar ultraviolet environment. 相似文献
77.
Molecular Diodes: Stable Molecular Diodes Based on π–π Interactions of the Molecular Frontier Orbitals with Graphene Electrodes (Adv. Mater. 10/2018) 下载免费PDF全文
78.
Decomposition of the acceleration levels distribution of a road transport into a sum of weighted Gaussians: Application to vibration tests 下载免费PDF全文
Anne‐Sophie Bonnin Jean‐Baptise Nolot Victor Huart Jérôme Pellot Nicolas Krajka Serge Odof Damien Erre 《Packaging Technology and Science》2018,31(8):511-522
The usual method to simulate vertical vibrations generated by road transport in laboratory is to use the average power spectral density. With this method, the distribution of the acceleration levels throughout the test is a Gaussian which does not conform to the reality of a transport. This study proposes an improvement of the classical method; this improvement permits to simulate the power spectral density and the distribution of acceleration levels by using a conventional device. The main idea of this method is to decompose the distribution of an actual road transport by using a sum of weighted Gaussians. Then, we apply the power spectral density with the root mean square acceleration (grms) level and duration corresponding to each Gaussian calculated from the weighted sum. We show that the weighting coefficients correspond to the time fraction of the test. Over the total duration of the test, we then retrieve the acceleration levels distribution of the actual transport. This new test method is experimentally validated with 2 examples of actual transports. 相似文献
79.
Kai Tao Wen Hu Bin Xue Drahomir Chovan Noam Brown Linda J. W. Shimon Oguzhan Maraba Yi Cao Syed A. M. Tofail Damien Thompson Junbai Li Rusen Yang Ehud Gazit 《Advanced materials (Deerfield Beach, Fla.)》2019,31(12)
Peptide assemblies are ideal components for eco‐friendly optoelectronic energy harvesting devices due to their intrinsic biocompatibility, ease of fabrication, and flexible functionalization. However, to date, their practical applications have been limited due to the difficulty in obtaining stable, high‐performance devices. Here, it is shown that the tryptophan‐based simplest peptide cyclo‐glycine‐tryptophan (cyclo‐GW) forms mechanically robust (elastic modulus up to 24.0 GPa) and thermally stable up to 370 °C monoclinic crystals, due to a supramolecular packing combining dense parallel β‐sheet hydrogen bonding and herringbone edge‐to‐face aromatic interactions. The directional and extensive driving forces further confer unique optical properties, including aggregation‐induced blue emission and unusual stable photoluminescence. Moreover, the crystals produce a high and sustained open‐circuit voltage (1.2 V) due to a high piezoelectric coefficient of 14.1 pC N?1. These findings demonstrate the feasibility of utilizing self‐assembling peptides for fabrication of biointegrated microdevices that combine high structural stability, tailored optoelectronics, and significant energy harvesting properties. 相似文献
80.