232 research outputs found
High Temperature and High Speed Digital Image Correlation Method for Dynamical Measurement of Thermal Shock
Most ceramic materials, because of their inherent brittleness, are susceptible to catastrophic failure under conditions of thermal shock. A novel method for measuring the dynamical deformation is proposed by using of high speed digital image correlation in high temperature environment. The nature texture of ceramic materials can be used as speckle while filters and monochrome produced by LED are applied to suppress black-body radiation and enhance the luminous intensity.
The light from the heated material can alter the Grayscale of material surface and the recognition for material surface will become more and more difficult with the temperature increase. In order to eliminate the affect of light radiation from high temperature object, an optical filter system is fixed on the lens. This optical filter can cut off almost all light except for the concerned light whose wavelength works for the range of filter and can almost filter the radiation from long wave band at hundreds of degrees Celsius. In our research, we success to conduct the thermal shock measurement with the high speed camera with 5000fps in the environment with the temperature of 1500C
Zika Virus Induced More Severe Inflammatory Response Than Dengue Virus in Chicken Embryonic Livers
Dengue (DENV) and Zika virus (ZIKV) are important flaviviruses in tropical and subtropical regions, causing severe Dengue Hemorrhagic Fever (DHF)/Dengue Shock Syndrome (DSS) and microcephaly, respectively. The infection of both viruses during pregnancy were reported with adverse fetal outcomes. To investigate the effects of ZIKV and DENV infections on fetal development, we established an infection model in chicken embryos. Compared with DENV-2, the infection of ZIKV significantly retarded the development of chicken embryos. High viral loads of both DENV-2 and ZIKV was detected in brain, eye and heart 7 and 11 days post-infection, respectively. Interestingly, only ZIKV but not DENV-2 was detected in the liver. Even both of them induced apparent liver inflammation, ZIKV infection showed a more severe inflammatory response than DENV-2 infection based on the inflammation scores and the gene expression levels of IL-1β, TNF, IL-6, and TGFβ-2 in liver. Our results demonstrated that ZIKV induced more severe inflammatory response in chicken embryo liver compared to DENV-2, which might partially attribute to viral replication in liver cells. Clinicians should be aware of the potential liver injury associated with ZIKV infection in patients, especially in perinatal fetuses
A Rapid Method for Measuring Strontium-90 Activity in Crops in China
A rapid method for measuring Sr-90 activity in crop ashes is presented. Liquid scintillation counting, combined with ion exchange columns 4‘, 4“(5“)-di-t-butylcyclohexane-18-crown-6, is used to determine the activity of Sr-90 in crops. The yields of chemical procedure are quantified using gravimetric analysis. The conventional method that uses ion-exchange resin with HDEHP could not completely remove all the bismuth when comparatively large lead and bismuth exist in the samples. This is overcome by the rapid method. The chemical yield of this method is about 60% and the MDA for Sr-90 is found to be 2:32 Bq/kg. The whole procedure together with using spectrum analysis to determine the activity only takes about one day, which is really a large improvement compared with the conventional method. A modified conventional method is also described here to verify the value of the rapid one. These two methods can meet di_erent needs of daily monitoring and emergency situation
Estrogen receptor α enhances the transcriptional activity of ETS-1 and promotes the proliferation, migration and invasion of neuroblastoma cell in a ligand dependent manner
Test and Analysis on Air Particulate Matter Concentration of a Subway Station in Chongqing
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