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851.
C W Ponton J J Eggermont S G Coupland R Winkelaar 《The Journal of the Acoustical Society of America》1992,91(3):1576-1586
Previous studies of human auditory development using frequency-specific auditory brain-stem responses (ABRs) have reported that maturation for both peak and interpeak latencies occurs earlier for responses generated by low-frequency stimuli. In two of these studies, low-frequency ABRs presumed to originate from apical locations in the cochlea were likely dominated by activity from higher frequency regions closer to the base. In the present study, the high-pass noise-masking technique was used to generate derived ABRs that represent activity from isolated place specific regions along the basilar membrane. Analysis of auditory brain-stem maturation based on I-V interpeak latency differences with adult means revealed a frequency-specific pattern of development. Developmental changes occurred faster and mature function was attained earlier for ABRs from the mid-center-frequency (CF) derived conditions than from either the highest or lowest CF derived conditions. The differential maturation of mid-CF derived ABRs may reflect the delayed effects of the pattern of development that occurs in the cochlea. 相似文献
852.
Gas-phase cigarette smoke (GPCS) was able to induce lipid peroxidation in lecithin liposomes, rat liver microsomes, and rat lung cells (RLC), and change the membrane fluidity of RLCs. Lipid free radicals were trapped in a GPCS-treated microsomal suspension by using 4-POBN as the spin trap. In addition, it was found that GPCS-peroxidized liposomes in appropriate degree of lipid peroxidation had the ability to increase the generation of superoxide anions in rat peritoneal neutrophils (RPN). Effects of green tea polyphenols (GTP) on the GPCS-induced damages were investigated The results showed that GTP was capable of inhibiting the GPCS-induced damages. 相似文献
853.
854.
Chang S.J. Chang C.S. Su Y.K. Lee C.T. Chen W.S. Shen C.F. Hsu Y.P. Shei S.C. Lo H.M. 《Advanced Packaging, IEEE Transactions on》2005,28(2):273-277
Nitride-based flip-chip indium-tin-oxide (ITO) light-emitting diodes (LEDs) were successfully fabricated. It was found that the forward voltage and the 20 mA output power of the flip-chip ITO LED were 3.32 V and 14.5 mW, respectively. Although the operation voltage of such a flip-chip ITO LED was slightly larger, it was found that its output power was much larger than those of conventional nonflip-chip LEDs. It was also found that flip-chip ITO LEDs were more reliable. 相似文献
855.
By integrating lithography and self‐assembly via electrohydrodynamic instabilities, Russel and co‐workers are able to guide initially flat polymer films to evolve into periodic arrays of pillars over regions much greater in extent than their natural domain sizes, as detailed on p. 1992. Novel structures that involve a combination of linear ridges and pillars are also produced, mainly as as result of the dynamic merging among preformed pillars. To pattern thin polymer films via electrohydrodynamic instabilities, we design and utilize two different kinds of mask patterns to guide pillars into alignment over regions much greater in extent than their natural domain sizes. First, narrow protruding ridges that intersect to form regular patterns on the mask trigger the growth of pillars beneath. Later, square and triangular packings of pillars develop in the regions enclosed by those ridges, preserving the registry from one domain to the next over a much larger area than within individual domains in unpatterned portions of the mask. Second, small square protrusions that are prealigned into a large regular array on the mask guide the formation of square packings of pillars in domains that conform to the mask, forming a large array of pillars. Novel structures involving a combination of linear ridges and pillars are also produced mainly due to the dynamic merging among preformed pillars. Finally, we find vertex symmetry of the mask pattern is necessary for generating and preserving ordered patterns on the polymer film. 相似文献
856.
Based on the Kachanov method and the alternating iteration technique, a new method is proposed to deal with the problem of the strongly interacted multiple cracks in an infinite plate. Unlike the Kachanov method which neglects the interaction of the tractions of the non-uniform components, the tractions of the non-uniform components on the surfaces of cracks are considered through the alternating technique. The accuracy and efficiency of present method are validated by comparing the results of two collinear and two parallel overlapped open the cracks obtained by the present method with those of the exact solutions, the results of the Kachanov method and the alternating iteration technique. Applications of present method in solving sliding close crack problems and evaluating the plastic zones demonstrate the versatility of present method. 相似文献
857.
858.
Liong S. Wong C.P. Burgoyne W.F. Jr. 《Components and Packaging Technologies, IEEE Transactions on》2005,28(2):327-336
Generally, isotropically conductive adhesive formulations include epoxy resin as the polymeric matrix. Although epoxy has superior adhesion capability, its drawbacks include the tendency to absorb moisture and lack of reworkability (thermosetting polymer). In this study, a thermoplastic polymer with low moisture absorption (0.28 wt%), called polyarylene ether (PAE2), is used in isotropically conductive adhesive (ICA) formulation. Previous research work by Lu et al. showed that the moisture absorbed into epoxy caused galvanic corrosion, which result in the formation of metal oxide . By using a polymer with low moisture absorption, the amount of water present in ICA will be small, and the corrosion rate and formation of metal oxide can be reduced. However, previous measurements of contact resistance stability of PAE2-based ICA showed that they are not stable on all surface finishes. It was determined that for thermoplastic-based ICA, poor adhesion was the main mechanism for unstable contact resistance. Two methods of adhesion improvement will be evaluated in this work. The first is to use coupling agents and the second is to blend the thermoplastic with epoxy. Both methods showed promise in improving the contact resistance stability of polyarylene ether based ICA. 相似文献
859.
A new system designed to measure the chromatic dispersion of installed single-mode fibres is presented. This system utilises the modulation phase technique but eliminates the reference laser and fibre. A large dynamic range was demonstrated by the measurement of an 81.1 km length of fibre. 相似文献
860.