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Dale L. Muccignat Peter W. Stokes Daniel G. Cocks Jason R. Gascooke Darryl B. Jones Michael J. Brunger Ronald D. White 《International journal of molecular sciences》2022,23(6)
The extraction of electron–liquid phase cross-sections (surface and bulk) is proposed through the measurement of (differential) energy loss spectra for electrons scattered from a liquid micro-jet. The signature physical elements of the scattering processes on the energy loss spectra are highlighted using a Monte Carlo simulation technique, originally developed for simulating electron transport in liquids. Machine learning techniques are applied to the simulated electron energy loss spectra, to invert the data and extract the cross-sections. The extraction of the elastic cross-section for neon was determined within 9% accuracy over the energy range 1–100 eV. The extension toward the simultaneous determination of elastic and ionisation cross-sections resulted in a decrease in accuracy, now to within 18% accuracy for elastic scattering and 1% for ionisation. Additional methods are explored to enhance the accuracy of the simultaneous extraction of liquid phase cross-sections. 相似文献
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Tensile and short beam shear tests were performed on five high strength vinyl ester molding compounds after immersion in water at various temperatures. These tests were conducted in order to characterize the degradation of these properties with environmental exposure and to isolate problem areas which contribute to the degradation. Reductions of up to 70 percent were found for both tensile and short beam shear strength, when tested at high temperatures. This loss of properties is primarily a result of degradation of the glass/resin interface and is essentially irreversible. 相似文献
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A numerical model of passive thermal nondestructive evaluation (NDE) of composite laminates was developed. This model, based on a transient, three-dimensional, finite difference solution to the heat conduction equations, can be used to characterize in-plane defects in the laminates and to predict the laminate response to the thermal test. The model was experimentally verified using two material systems. A parametric study was then conducted to ascertain which variables were critical to the success of passive thermal NDE, and how flaw resolution might be improved. 相似文献
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Safety Evaluation of Green Tea Polyphenols Consumption in Middle‐aged Ovariectomized Rat Model
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Chwan‐Li Shen Gordon Brackee Xiao Song Michael D. Tomison VelvetLee Finckbone Kelly T. Mitchell Lili Tang Ming‐Chien Chyu Dale M. Dunn Jia‐Sheng Wang 《Journal of food science》2017,82(9):2192-2205
This work evaluates chronic safety in middle‐aged ovariectomized rats supplemented with different dosages of green tea polyphenols (GTP) in drinking water. The experiment used 6‐mo‐old sham (n = 39) and ovariectomized (OVX, n = 143) female rats. All sham (n = 39) and 39 of the OVX animals received no GTP treatment and their samples were collected for outcome measures at baseline, 3 mo, and 6 mo (n = 13 per group for each). The remaining OVX animals were randomized into 4 groups receiving 0.15%, 0.5%, 1%, and 1.5% (n = 26 for each) of GTP (wt/vol), respectively, in drinking water for 3 and 6 mo. No mortality or abnormal treatment‐related findings in clinical observations or ophthalmologic examinations were noted. No treatment‐related macroscopic or microscopic findings were noted for animals administered 1.5% GTP supplementation. Throughout the study, there was no difference in the body weight among all OVX groups. In all OVX groups, feed intake and water consumption significantly decreased with GTP dose throughout the study period. At 6 mo, GTP intake did not affect hematology, clinical chemistry, and urinalysis, except for phosphorus and blood urea nitrogen (increased), total cholesterol, lactate dehydrogenase, and urine pH (decreased). This study reveals that the no‐observed‐adverse‐effect level (NOAEL) of GTP is 1.5% (wt/vol) in drinking water, the highest dose used in this study. 相似文献
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