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61.
Results of 3-year full-scale field climatic tests on application of five types of inhibiting papers for anticorrosion protection of ferrous and nonferrous metals during storage in a humid tropical climate have been carried out by the Joint Russian and Vietnamese Tropical Research and Technology Center and presented here. It has been shown that the inhibiting paper IPCAS-118 can be recommended for anticorrosion protection of equipment made of steel, copper, and aluminum during 3-year storage in sheds in humid tropical climate conditions  相似文献   
62.
In this paper, we demonstrated the Inkjet print method to fabricate a ultraviolet (UV)-curable epoxy microlens deflecting array with controllable curvature and filling factor, by which a 7-in light guide plate with 82% uniformity and 70% light efficiency was successfully implemented. The microlenses can be directly formed by plastic discharged by inkjet head, eliminating the need for molds and slashing development time. Proposed method will certainly has a promising impact on rapid prototyping and other specialized microfeatures due to its simplicity and versatility.  相似文献   
63.
Three methods which can be applied to extract quantitative information on the effect of deposition on filter performance from effluent concentration and pressure drop data were developed. It was found that all three methods are capable of describing the deposition effect in terms of the amount of deposited particles. Furthermore, the method of extrapolation was found to give the most consistent, if not the most accurate, interpretation of experimental data.  相似文献   
64.
This paper documents the effect of stress and temperature on the cyclic minimum strain rate at two different loading frequencies for the oxide dispersion strengthened (ODS) superalloy, INCONEL* MA 6000. The apparent stress exponent and activation energy for cyclic creep at both frequencies studied are shown to be greater than values observed for static creep. The large values of the stress exponent and activation energy for cyclic creep are proposed to result from anelastic strain storage delaying nonrecoverable creep during the on-load portion of the cyclic creep loading, such that the “effective stress” driving nonrecoverable creep is only a small fraction of the applied stress. In addition, the temperature dependence of the anelastic relaxation that occurs during the off-load portion of the cyclic creep loading is determined. The activation energy found for the relaxation process is equal to about one-half that for self-diffusion in nickel. A mechanism of localized climb of dislocations over the oxide dispersoids present in INCONEL MA 6000 is postulated to account for the observed activation energy of the relaxation process. VINCENT C. NARDONE, formerly Associate Research Scientist, Henry Krumb School of Mines, Columbia University  相似文献   
65.
We have used transmission electron microscopy, high-resolution Rutherford backscattering spectrometry (HRBS), and angle-resolved X-ray photoelectron spectroscopy (ARXPS) to investigate the interfacial oxidized states of hafnium oxide/silicon oxide/Si gate oxide stacks. The atomic concentrations and profiles of HRBS analysis are similar before and after annealing; however, ARXPS shows a clear difference in bond status. These results imply that weakly bonded oxygen atoms existed in the stacks alongside the suboxides. In the as-deposited layers, dioxides are found at the interfaces and suboxides in the layers whereas after annealing suboxides are found at the interfaces and dioxides are found in the layers because of redistribution of bonds during annealing. The combination of HRBS and ARXPS analyses indicated that the main oxidized states transformed from the suboxides to the dioxides with no obvious quantitative difference in the content of oxygen atoms, suggesting that reactions of the weakly bonded oxygen atoms occurred with the suboxides within the layers.  相似文献   
66.
Metallurgical and Materials Transactions A - Cyclic creep and stress rupture results are reported and discussed as a function of the lower applied load for INCONEL MA6000, which is a mechanically...  相似文献   
67.
68.
Our previous study showed that a single lipopolysaccharide (LPS) treatment to neonatal rats could induce a long-lasting neuroinflammatory response and dopaminergic system injury late in life. This is evidenced by a sustained activation of microglia and elevated interleukin-1β (IL-1β) levels, as well as reduced tyrosine hydroxylase (TH) expression in the substantia nigra (SN) of P70 rat brain. The object of the current study was to test whether co-administration of IL-1 receptor antagonist (IL-1ra) protects against LPS-induced neurological dysfunction later in life. LPS (1 mg/kg) with or without IL-1ra (0.1 mg/kg), or sterile saline was injected intracerebrally into postnatal day 5 (P5) Sprague-Dawley male rat pups. Motor behavioral tests were carried out from P7 to P70 with subsequent examination of brain injury. Our results showed that neonatal administration of IL-1ra significantly attenuated LPS-induced motor behavioral deficits, loss of TH immunoreactive neurons, as well as microglia activation in the SN of P70 rats. These data suggest that IL-1β may play a pivotal role in mediating a chronic neuroinflammation status by a single LPS exposure in early postnatal life, and blockading IL-1β might be a novel approach to protect the dopaminergic system against perinatal infection/inflammation exposure.  相似文献   
69.
Wireless sensor networks (WSNs) are well suited to many applications, including environment surveillance and target tracking. ZigBee is an IEEE 802.15.4‐based standard that is considered suitable for WSNs. The functional operations of a ZigBee network rely on self‐organized network connections and the proper deployment of sensor devices. However, the devices comprising a ZigBee network may become isolated from the network after the joining phase due to the configuration constraints of the ZigBee standard. This means that some deployed devices cannot join the network even though they can communicate with other joined nodes. These isolated devices reduce the efficiency of network operation and increase deployment costs. This paper proposes a ZigBee‐compatible adaptive joining mechanism with connection shifting schemes to improve the connectivity of ZigBee networks, allowing them to operate at the expected efficiency. Simulation results show that the proposed mechanism significantly improves the join ratio of deployed sensor devices in ZigBee WSNs. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
70.
The thiodiphenyl epoxy (THEP) was prepared by the 4,4′‐thiodiphenol (THDOL) and the epichlorohydrin (ECH) without using any NaOH or KOH catalysts. The THEP possessed weak hydrogen bonding in the cured THEP/DGEBA system. The intermolecular motion parameters k and q were 0.26 and ?168.5, respectively, which determined by the Gordon‐Taylor and Kwei equations. The soft sulfide linkage (? S? ) of the THEP degraded at lower temperature than cured DGEBA material, and further to form various thermal stable sulfate derivative chars. The char yields increased from 11.43 to 25.94 wt % and from 0.65 to 1.04 wt % in the nitrogen and air, respectively. Introduction of the THEP into the DGEBA could provide the antioxidation thermal property and improve the thermal stability of the DGEBA epoxy in the air. In the air atmosphere, the activation energies of the second thermal degradation were increased from 66.67 to 103.42 kJ/mol. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
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