75 research outputs found
GT2010-23809 SINTERING BEHAVIOR OF PLASMA-SPRAYED Sm 2 Zr 2 O 7 COATING
ABSTRACT Plasma-sprayed thermal barrier coating (TBC) systems are widely used in gas turbine blades to increase turbine entry temperature (TET) and better efficiency. Yttria stabilized zirconia (YSZ) has been the conventional thermal barrier coating material because of its low thermal conductivity, relative high thermal expansion coefficient and good corrosion resistance. However the YSZ coatings can hardly fulfill the harsh requirements in future for higher reliability and the lower thermal conductivity at higher temperatures. Among the interesting TBC candidates, materials with pyrochlore structure show promising thermo-physical properties for use at temperatures exceeding 1200 ºC. Sm 2 Zr 2 O 7 bulk material does not only have high temperature stability, sintering resistance but also lower thermal conductivity and higher thermal expansion coefficient. The sintering characteristics of ceramic thermal barrier coatings under high temperature conditions are complex phenomena. In this paper, samarium zirconate (Sm 2 Zr 2 O 7 , SZ) powder and coatings were prepared by solid state reaction and atmosphere plasma spraying process, respectively. The microstructure development of coatings derived from sintering after heat-treated at 1200-1500 ºC for 50 h have been investigated. The microstructure was examined by scanning electron microscopy (SEM) and the grain growth was analyzed in this paper as well
High Human Bocavirus Viral Load Is Associated with Disease Severity in Children under Five Years of Age
Human bocavirus (HBoV) is a parvovirus and detected worldwide in lower respiratory tract infections (LRTIs), but its pathogenic role in respiratory illness is still debatable due to high incidence of co-infection with other respiratory viruses. To determine the prevalence of HBoV infection in patients with LRTI in Shanghai and its correlation with disease severity, we performed a 3-year prospective study of HBoV in healthy controls, outpatients and inpatients under five years of age with X-ray diagnosed LRTIs. Nasopharyngeal aspirates were tested by PCR for common respiratory viruses and by real time PCR for HBoV subtypes 1–4. Nasopharyngeal swabs from healthy controls and serum samples and stools from inpatients were also tested for HBoV1-4 by real time PCR. Viral loads were determined by quantitative real time PCR in all HBoV positive samples. HBoV1 was detected in 7.0% of inpatients, with annual rates of 5.1%, 8.0% and 4.8% in 2010, 2011 and 2012, respectively. Respiratory syncytial virus (RSV) subtype A was the most frequent co-infection detected; HBoV1 and RSVA appeared to co-circulate with similar seasonal variations. High HBoV viral loads (>10(6) copies/ml) were significantly more frequent in inpatients and outpatients than in healthy controls. There was a direct correlation of high viral load with increasing disease severity in patients co-infected with HBoV1 and at least one other respiratory virus. In summary, our data suggest that HBoV1 can cause LRTIs, but symptomatic HBoV infection is only observed in the context of high viral load
Effect of crystallite size and calcination temperature on the thermal stability of single nanocrystalline chromium oxide: expressed by novel correlation
A Study on Aging Characteristics of Silicone Oil in HV Oil-filled Cable Termination Based on Infrared Thermal Imaging Test
In order to assess the aging characteristics of Silicone oil in the high voltage oil-filled cable termination after being operated 12 years, the silicone oil in service were studied using the infrared imaging detection, Fourier infrared spectrum analysis, and dielectric properties and micro water content test. The relationship between the infrared thermal imaging temperature and the physical and chemical properties was considered. The results indicate that, the operating temperature of silicone oil within the terminal based on the infrared thermal imaging testing can be characterization of silicone oil aging state. The aging characteristic peak of Silicone oil is P-H key stretching vibration peak, which is near 2360cm− 1, Si-CH3, -CH3 and Si-O-Si keys have no influence of before and after aging. In addition, the aging properties of silicone oil can be reviewed by the change of the dielectric properties, and the decline of the dielectric properties is caused by the aging and water content of materials. The results will be helpful for research of silicone oil aging and optimization design of anti-aging, serving as references for the manufacture, design, and operation
Research progress of superhydrophobic-superoleophilic 3D elastic porous materials applied to the marine oil spill treatment
The marine oil spill accidents will not only result in the waste of energy, but also the unrecoverable destruction of the ecological environment. The superhydrophobic-superoleophilic 3D elastic porous materials are the most efficient oil adsorbents for the marine oil spill treatment, due to its low density, high porosity, strong elasticity, large oil adsorbing capacity and the convenient recovery of the materials and oil. Herein, based on the theoretical basis and the construction principles of the superhydrophobic-superoleophilic surface, the latest research progress was reviewed for three types of the superhydrophobic-superoleophilic 3D elastic porous materials respectively, i.e. the polymer-based, the carbon-based and the organism-based materials, in terms of the specific materials, the preparation method, and the application performance. Finally, the merits, defects and the faced challenges of the three types of the superhydrophobic-superoleophilic 3D elastic porous materials during their preparation and application were summarized, and the prospect was made for the development in future
Investigation of the mechanism of binding of thiacloprid to human serum albumin using spectroscopic techniques and molecular modeling methods
Abstract. Fluorescence spectroscopy, UV absorption, circular dichroism (CD) spectroscopy and molecular modeling methods were used to characterize the binding properties of thiacloprid (TL) with human serum albumin (HSA) at molecular level under physiological conditions. The fluorescence intensity of HSA decreased regularly with the gradually increasing concentration of thiacloprid. The binding constant K at three different temperatures (290, 300 and 310 K) were 3.07, 2.74 and 1.35 × 10 4 M −1 , respectively, for TL-HSA interaction have been calculated from the relevant fluorescence data. CD spectroscopic measurements have shown that the secondary structures of the protein have been changed by the interaction of thiacloprid with HSA. Furthermore, the study of molecular modeling indicated that thiacloprid could be located on the surface of the binding pocket of subdomains IIA in HSA. The hydrophobic interaction was the major acting force and there are H-bonds and electrostatic interactions between TL and HSA, which is in good agreement with the results from the experimental thermodynamic parameters (the enthalpy change ΔH 0 and the entropy change ΔS 0 were calculated to be −20.378 kJ/mol and 16.328 J/mol K according to the Van't Hoff equation)
PREPUBLICATION: Isothermal crystallization properties and waxy crude 1 oil rheological improving performance of polyoctadecylacrylate/ organically modified montmorillonite composite pour point depressant
A Study on Aging Characteristics of Silicone Oil in HV Oil-filled Cable Termination Based on Infrared Thermal Imaging Test
In order to assess the aging characteristics of Silicone oil in the high voltage oil-filled cable termination after being operated 12 years, the silicone oil in service were studied using the infrared imaging detection, Fourier infrared spectrum analysis, and dielectric properties and micro water content test. The relationship between the infrared thermal imaging temperature and the physical and chemical properties was considered. The results indicate that, the operating temperature of silicone oil within the terminal based on the infrared thermal imaging testing can be characterization of silicone oil aging state. The aging characteristic peak of Silicone oil is P-H key stretching vibration peak, which is near 2360cm− 1, Si-CH3, -CH3 and Si-O-Si keys have no influence of before and after aging. In addition, the aging properties of silicone oil can be reviewed by the change of the dielectric properties, and the decline of the dielectric properties is caused by the aging and water content of materials. The results will be helpful for research of silicone oil aging and optimization design of anti-aging, serving as references for the manufacture, design, and operation
Composite Differential Evolution with Modified Oracle Penalty Method for Constrained Optimization Problems
Motivated by recent advancements in differential evolution and constraints handling methods, this paper presents a novel modified oracle penalty function-based composite differential evolution (MOCoDE) for constrained optimization problems (COPs). More specifically, the original oracle penalty function approach is modified so as to satisfy the optimization criterion of COPs; then the modified oracle penalty function is incorporated in composite DE. Furthermore, in order to solve more complex COPs with discrete, integer, or binary variables, a discrete variable handling technique is introduced into MOCoDE to solve complex COPs with mix variables. This method is assessed on eleven constrained optimization benchmark functions and seven well-studied engineering problems in real life. Experimental results demonstrate that MOCoDE achieves competitive performance with respect to some other state-of-the-art approaches in constrained optimization evolutionary algorithms. Moreover, the strengths of the proposed method include few parameters and its ease of implementation, rendering it applicable to real life. Therefore, MOCoDE can be an efficient alternative to solving constrained optimization problems
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