多媒体银行电视监控系统

以多媒体计算机为控制核心，运用RS-485通讯技术及网络通讯技术，设计了一种现代银行多媒体监控系统，实现了对各监视点的控制及报警联动．实用表明，该系统智能化程度高，性能稳定，易于操作．     

Kondensation von p-Nitrosodimethylanilin mit Resorcinderivaten

Zusammenfassung p-Nitrosodimethylanilin wurde mit Resorcinderivaten zu 7-Dimethylaminophenoxazonen-(3) kondensiert.     

Applications of the direct Trefftz boundary element method to the free-vibration problem of a membrane

In this paper, the direct Trefftz method is applied to solve the free-vibration problem of a membrane. In the direct Trefftz method, there exists no spurious eigenvalue. However, an ill-posed nature of numerical instability encountered in the direct Trefftz method requires some treatments. The Tikhonov's regularization method and generalized singular-value decomposition method are used to deal with such an ill-posed problem. Numerical results show the validity of the current approach.     

Pseudo-polyrotaxane and beta-sheet layer-based three-dimensional coordination polymers constructed with silver salts and flexible pyridyl-type ligands

A fascinating 3D pseudo-polyrotaxane architecture with 1D polymeric [Ag(bpp)](n) chains penetrating 2D (6,3) [Ag(2)(bpp)(2)(ox)](n) sheets and a 3D coordination network constructed with 2D infinite [Ag(ppa)](n) beta-sheetlike layers pillared by ox ligands (bpp = 1,3-bis(4-pyridyl)propane; ppa = N-(4-pyridinylmethyl)-4-pyridinecarboxamide; ox = oxalate) have been prepared by utilizing flexible pyridyl-type ligands and have been crystallographically characterized. Crystal data for 1: monoclinic, space group C2/c, a = 7.619(2) A, b = 19.781(4) A, c = 26.799(5) A, beta = 94.720(10) degrees, U = 4025.2(15) A(3), and Z = 4. Crystal data for 2: monoclinic, space group C2/c, a = 28.947(8) A, b = 8.617(3) A, c = 16.307(6) A, beta =121.07(1) degrees, U = 3484(2) A(3), and Z = 4.     

Spectro-temporal modulation transfer functions and speech intelligibility

Detection thresholds for spectral and temporal modulations are measured using broadband spectra with sinusoidally rippled profiles that drift up or down the log-frequency axis at constant velocities. Spectro-temporal modulation transfer functions (MTFs) are derived as a function of ripple peak density (omega cycles/octave) and drifting velocity (omega Hz). The MTFs exhibit a low-pass function with respect to both dimensions, with 50% bandwidths of about 16 Hz and 2 cycles/octave. The data replicate (as special cases) previously measured purely temporal MTFs (omega = 0) [Viemeister, J. Acoust. Soc. Am. 66, 1364-1380 (1979)] and purely spectral MTFs (omega = 0) [Green, in Auditory Frequency Selectivity (Plenum, Cambridge, 1986), pp. 351-359]. A computational auditory model is presented that exhibits spectro-temporal MTFs consistent with the salient trends in the data. The model is used to demonstrate the potential relevance of these MTFs to the assessment of speech intelligibility in noise and reverberant conditions.     

Long-term average spectrum of Spanish

The long-term average spectrum of Spanish, as spoken in Mexico, was obtained for thirty subjects—fifteen men and fifteen women. To obtain the average spectrum, use was made of a digital system comprised of an FFT analyzer interfaced to a microcomputer. All data acquisition, storage and processing was thus digital. The main features of the average spectrum are: peaks in the region of 240 Hz and 500 Hz, a ?20 dB/octave slope from 0·5 kHz to 1 kHz; a flat region between 1 kHz and 2 kHz, a further decline of ?10 dB/octave to ≈3 kHz and, finally, a large flat region (within 5 dB) from 3 kHz up to 10 kHz. These results agree reasonably well with some other studies for English. The technique employed here is thus adequate for this kind of study, being relatively fast and easy to implement.     

Simultaneous electroosmotic and permeation flows through a Nafion membrane. 1. Aqueous electrolyte solutions

The volume flow through a Nafion membrane originated by the simultaneous action of an electric potential difference and a pressure difference has been measured using aqueous KCl solutions under different experimental conditions. The behavior has been analyzed when both gradients act in the same and in the opposite sense. The results indicate that the simultaneous action of the pressure and potential differences originates a total flow different from the sum of the electroosmotic and permeation flows due to each force acting separately. The application of irreversible thermodynamics, which includes second-order terms, allowed the determination of the phenomenological coefficients. Moreover, from these values, the equivalent pore radius was estimated on the assumption that the membrane is a porous medium filled with an internal solution.     

Raman analysis of defects in n-type 4H-SiC

This paper employs micro-Raman technique for detailed analysis of the defects (both inside and outside) in bulk 4H-SiC. The main peaks of the first-order Raman spectrum obtained in the centre of defect agree well with those of perfect bulk 4H-SiC, which indicate that there is no parasitic polytype in the round pit and the hexagonal defect. Four electronic Raman scattering peaks from nitrogen defect levels are observed in the round pit (395\,cm$^{-1}$, 526\,cm$^{-1}$, 572\,cm$^{-1}$, and 635\,cm$^{-1})$, but cannot be found in the spectra of hexagonal defect. The theoretical analysis of the longitudinal optical plasmon--phonon coupled mode line shape indicates the nonuniformity of nitrogen distribution between the hexagonal defect and the outer area in 4H-SiC. The second-order Raman features of the defects in bulk 4H-SiC are well-defined using the selection rules for second-order scattering in wurtzite structure and compared with that in the free defect zone.