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61.
Interfaces of the babbitt metal-bronze composite were examined ultrasonically and were fractured using the Chalmers test method. It was found that the ultrasonic results correlated with the bond strength, the ductility, and the degree of bonding at the tested interface. Specifically, high ultrasonic reflection percentages were associated with low bond strength, low ductility, and low percentages of bonded regions. The fracture mechanism in the bonded area of the babbitt-bronze interface is related to the presence of the intermetallic compound, Cu6Sn5, at the interface. It is suggested that the non-destructive ultrasonic technique can detect the bond integrity of babbitted metals.  相似文献   
62.
Whey protein isolate (WPI) films (pH 5.2) containing 0.5 to 1.0% p‐aminobenzoic acid (PABA) and/or sorbic acid (SA) were assessed for antimicrobial and mechanical properties while in contact with sliced bologna and summer sausage that were inoculated with Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica subsp. enterica serovar Typhimurium DT104. WPI films containing SA or PABA decreased L. monocytogenes, E. coli, and S. Typhimurium populations by 3.4 to 4.1,3.1 to 3.6, and 3.1 to 4.1 logs, respectively, on both products after 21 d at 4 °C. Background flora was inhibited compared with controls. Film tensile strength decreased while % elongation remained unchanged following 72 h of product contact.  相似文献   
63.
In this study, the authors presented synthesis of ceria nanoparticles (NPs) by the bio‐reduction method and their antioxidative activity. Aqueous extract of Euphorbia (Euphorbia amygdaloides) was used as reducing and stabilising agents. They used aqueous extract of Euphorbia (E. amygdaloides) as reducing and stabilising agent. Ultraviolet–visible (UV–vis) absorption spectroscopy was used to monitor the quantitative formation of ceria NPs. They also addressed the characteristics of the obtained ceria NPs using scanning electron microscopy (SEM), X‐ray diffraction (XRD) and transmitting electron microscope (TEM). The synthesised cerium (III) oxide (Ce2 O3) NPs were initially noted through visual colour change from colourless pale yellow cerium (III) to light yellow cerium (IV) and further confirmed the band at 345 nm employing UV–vis spectroscopy. The average diameter of the prepared NPs was about 8.6–10.5 nm. In addition, the synthesised Ce2 O3 NPs were tested for antioxidant and anti‐bacterial activities using ferric reducing antioxidant power, cupric reducing antioxidant capacity, ferrous ions chelating activity, superoxide the anion radical scavenging and 2, 2′‐azinobis 3‐ethylbenzothiazol to‐6‐sulphonic acid scavenging activity. It could be concluded that Euphorbia (E. amygdaloides) extract can be used efficiently in the production of potential antioxidant and anti‐bacterial Ce2 O3 NPs for commercial applications.Inspec keywords: cerium compounds, nanoparticles, nanofabrication, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet spectra, visible spectraOther keywords: Ce2 O3 , α‐tocopherol, butylated hydroxytoluene, anion radical scavenging, ferrous ions chelating activity, 2, 2''‐azinobis 3‐ethylbenzothiazol to‐6‐sulphonic acid scavenging activity, UV‐vis spectroscopy, light yellow cerium, ultraviolet‐visible absorption spectroscopy, SEM, XRD, green synthesis, transmitting electron microscopy, X‐ray diffraction, scanning electron microscopy, aqueous extract Euphorbia amygdaloides, antioxidative activity, bio‐reduction method, ceria nanoparticles, antioxidant activity  相似文献   
64.
Y. Delaviz  A. Gungor  J.E. McGrath  H.W. Gibson   《Polymer》1992,33(24):5346-5347
A phosphine oxide containing aromatic polyester has been synthesized by the direct polycondensation reaction of bis[4-(m-carboxyphenoxy)phenyl]phenylphosphine oxide (m-BCPPO) and 4,4′-isopropylidene-diphenol (bisphenol A). The presence of phosphine oxide linkages in the backbone gives this polymer superior properties: namely thermo-oxidative stability, high char yield and solubility in common organic solvents.  相似文献   
65.
In this research, formaldehyde-free dual-curable adhesive formulations containing polyvinyl butyral (PVB) were prepared with the reaction of 2,4-toluene diisocyanate (TDI) and 2-hydroxyethyl methacrylate (HEMA) and then applied on cord fabrics upon adhere onto the rubber surfaces. The effects of PVB ratio on peel strength value between the cord and rubber were studied. The structure of the oligomer was characterized by FTIR and 1H NMR spectroscopy. Thermal properties of coated and UV-cured fabrics were investigated by TGA and DSC. Surface wettability properties of the fabrics after coating were observed with contact angle measurement. The peel strength between cord/rubber surfaces was determined by T-peel test after thermal curing stage under heat and pressure. Results showed that peel strength value increases with increasing PVB amount in the formulation. The highest peel strength of 94.7 N/cm was observed when 5% PVB was included in the formulation. This study leads to a new type of promising adhesives with superior peel strength for cord/rubber applications as it is being a totally formaldehyde-free process.  相似文献   
66.
The application of fractional melting to IN-l00 cast nickel-basesuperalloy can reduce its microporosity and lower the amount of γ+ γ’ eutectic. It can also homogenzze the dendritic eutectic and grain boundary segregations, which are greatly znfluenced by the applied pressure and maximum pressing temperature. After fractional melting the . . size and morphology of γ’ and the eutectic are slightly different, and some M23C6 preczpztates out. Chemical composition is little changed below 1323°C.  相似文献   
67.
68.
Multimedia and delay-sensitive data applications in cognitive radio sensor networks (CRSN) require efficient real-time communication and dynamic spectrum access (DSA) capabilities. This requirement poses emerging problems to be addressed in inherently resource-constrained sensor networks, and needs investigation of CRSN challenges with real-time communication requirements. In this paper, the main design challenges and principles for multimedia and delay-sensitive data transport in CRSN are introduced. The existing transport protocols and algorithms devised for cognitive radio ad hoc networks and wireless sensor networks (WSN) are explored from the perspective of CRSN paradigm. Specifically, the challenges for real-time transport in CRSN are investigated in different spectrum environments of smart grid, e.g., 500 kV substation, main power room and underground network transformer vaults. Open research issues for the realization of energy-efficient and real-time transport in CRSN are also presented. Overall, the performance evaluations provide valuable insights about real-time transport in CRSN and guide design decisions and trade-offs for CRSN applications in smart electric power grid.  相似文献   
69.
The prediction of elastic constants of open‐mesh diamond braids has not been adequately studied. The objective of this work is to provide a further comparison of longitudinal elastic and shear moduli regression equations previously developed with experimental data from in‐house experiments; to determine the regression equations linearity limits; and to provide a validated predictive model for E x, E y and G xy for large open mesh composites. The results of the model match well with experimental findings for close‐mesh braided composites; however, for open‐mesh braided composites the results show differences. Also, the lower linearity limit (LLL) of the model for different fiber‐matrix systems were calculated and discussed. The comparison of initial experimental findings of the open‐mesh structures and the model suggests a full characterization of the model can be possible by increasing the experimental data pool in the literature which is currently very limited. POLYM. COMPOS., 2011. © 2010 Society of Plastics Engineers  相似文献   
70.
Suitability of acid whey (AW) as brine media in fermented and fresh-pack cornichon pickle production was investigated. Fermented and fresh-pack pickles were produced with AW and vinegar (control). Microbiological, textural, colour and sensory properties of the pickles were monitored during 12-wk storage at room temperature. Fermented and fresh-pack pickles manufactured with AW exhibited higher total solids content than the pickles manufactured with vinegar. Acid whey as pickling media increased the development of presumptive lactococci species both in fermented and in fresh-pack pickles. This study shows that AW is a suitable pickling media for fermented and fresh-pack cornichon pickle manufacture.  相似文献   
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