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31.
Acta Mathematicae Applicatae Sinica, English Series - We present some exact integrability cases of the extended Liénard equation y″ + f(y)(y′)n + k(y)(y′)m + g(y)y′ +...  相似文献   
32.
Periodica Mathematica Hungarica - We prove that the inequality $$\begin{aligned} \Gamma (x+1)\le \frac{x^2+\beta }{x+\beta } \end{aligned}$$ holds for all $$x\in [0,1]$$ , $$\beta \ge {\beta...  相似文献   
33.
Derived-band auditory brainstem responses (ABRs) were obtained in 43 normal-hearing and 80 cochlear hearing-impaired individuals using clicks and high-pass noise masking. The response times across the cochlea [the latency difference between wave V's of the 5.7- and 1.4-kHz center frequency (CF) derived bands] were calculated for five levels of click stimulation ranging from 53 to 93 dB p.-p.e. SPL (23 to 63 dB nHL) in 10-dB steps. Cochlear response times appeared to shorten significantly with hearing loss, especially when the average pure tone (1 to 8 kHz) hearing loss exceeded 30 dB. Examination of derived-band latencies indicates that this shortening is due to a dramatic decrease of wave V latency in the lower CF derived band. Estimates of cochlear filter times in terms of the number of periods to maximum response (Nmax) were calculated from derived-band latencies corrected for gender-dependent cochlear transport and neural conduction times. Nmax decreased as a function of hearing loss, especially for the low CF derived bands. The functions were similar for both males and females. These results are consistent with broader cochlear tuning due to peripheral hearing loss. Estimating filter response times from ABR latencies enhances objective noninvasive diagnosis and allows delineation of the differential effects of pathology on the underlying cochlear mechanisms involved in cochlear transport and filter build-up times.  相似文献   
34.
The reaction cross section σRpA(E) for proton-nucleus collisions varies with energy as the total cross section σtpN(E) does for proton-nucleon scattering in the energy regime 100 MeV ? E ?400 GeV. We propose several empirical relations, and test them by a χ2 analysis of various data. Within the framework of Glauber theory, the parameters in the relations can be linked to the cross section for a single inelastic collision.  相似文献   
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We present measurements from a spark chamber experiment of the differential cross-sections for pp → π?π+, K?K+ at 20 momenta in the range 0.8–2.4 GeV/c (c.m. energy 2.02 to 2.57 GeV). The c.m. angular range was ?0.95 < cosθ1 < 0.95. There are about 2000π?π+ events and about 300 K?K+ events at each momentum.  相似文献   
38.
In order to obtain a better understanding of the X1Σ+ ground state and the A1Σ+ state potential energy curves of lithium hydride and to examine in detail the concept of “mass-reduced quantum numbers” for both an ordinary (X1Σ+) and an anomalous (A1Σ+) electronic state, the emission spectra of the A1Σ+X1Σ+ bands of the isotopic lithium hydrides and deuterides were photographed in the 3000–5000-Å region with a 3.4-m Ebert Spectrograph. The bands found involved v″ = 0 to 7 to various v′ = 0 to 17 for 6LiH, and v″ = 0 to 7 to various v′ = 1 to 16 for 6LiD. Additional bands involving v″ = 4 and 5 were also found for 7LiH. The vibrational-rotational spectroscopic analysis of 7LiH, 6LiH, and 6LiD are reported here, as are the reanalyses of the 7LiH and 7LiD data reported by Crawford and Jorgensen. New Rydberg-Klein-Rees (RKR) A1Σ+ and X1Σ+ potential curves have been constructed for each individual molecule and are reported, but detailed isotopic comparisons will be reported in subsequent publications.  相似文献   
39.
Computer graphics-assisted applications of first-order chemical kinetics are applied to absorbance data from spectrophotometric measurements of the decomposition of di-μ-hydroxobis[dioxalatocobaltate(III)] (at pH 4.0) and trioxalatocobaltate(III) (in 1.0 M perchloric acid) in order to estimate the purity of the complexes. A program called KINFIR is used.  相似文献   
40.
以桑蚕丝为模板制备多级生物形态结构ZrO2-CeO2. 整个合成过程是由桑蚕丝模板的导向作用决定的. 分析结果表明ZrO2-CeO2结晶良好,呈多级网络中空纤维结构,直径为16~28μm,800 oC煅烧后ZrO2-CeO2晶粒尺寸约为14 nm.  相似文献   
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