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Tracking a mobile radio emitter in a high clutter environment with low signal to noise ratio is a challenging task due to high miss detection and false alarm rates in the joint time difference of arrival (TDOA) and frequency difference of arrival (FDOA) estimation procedure. To increase the probability of detection, multiple TDOA-FDOA measurements from a number of peaks in the cross ambiguity function...
The communication and detection signal become hard to recognize after they go through the underwater channel. To enhance the underwater signal, the functional link theory is introduced. According to the characteristic of the underwater signals, some improvements are made based on the split functional link adaptive filter. Experiment shows that the split functional link adaptive filter is fit for the...
In this paper, a calibration method is proposed for a nonplanar array with arbitrary geometry. This method can estimate the errors of array sensor position, gain and phase simultaneously using known calibration sources. Note that the technique does not use iterative calculation in estimating the array parameters and hence it has no convergent problem. However, it requires that four directions of arrival...
The separation/enrichment of tilmicosin was studied based on the system of aqueous two phase-gas solvent subblation, the method of HPLC was established to determin tilmicosin enriched. The optimal condition of the solvent sublation was obtained: the sublation solvent was n-propanol, the salting-out agent was (NH4)2SO4 with 36% (g/100ml), the pH was 3, N2 flow rate was 20 ml/min, the sublation time...
Ionic liquid aqueous two-phase flotation (ILATPF) consisting of ionic liquid aqueous two-phase system (ILATPS) and solvent sublation (SS), which is a novel, non-toxic and green sample pretreatment technique coupled with molecular fluorescence spectrophotometry, was developed for the simultaneous separation, enrichment and rapid analysis of acetylspiramycin. In this ILATPF system of 1-butyl-3-methylimidazolium...
Combining solvent sublation with ionic liquid aqueous two-phase extraction (ILATPE), ionic liquid aqueous two-phase flotation (ILATPF) was proposed for preconcentration and separation of antibiotics in environment. The new technique was applied to preconcentrate and separate trace roxithromycin (ROX) in the environment using 1-butyl-3-methylimidazolium-tetrafluoroborate ([Bmim]BF4) ionic liquid as...
Pb(II) and Cu(II) ion imprinted polymer particles were prepared by the combination of surface molecular imprinting technique and sol-gel process in acetic acid solution, with Pb(II) or Cu(II) ion as a template, CTS as functional monomer, and KH-560 as the cross-linker. The configuration of ion imprinted polymer and its materials were characterized by FT-IR spectra, UV-spectra. The optimal adsorption...
The feature extraction and target recognition of low-velocity targets near the port is difficult in signal processing. After the spectral characteristics of low-velocity targets are analyzed, the paper uses 1(1/2)-spectrum as the method of feature extraction. The advantages are as follow. 1(1/2)-spectrum can suppress the Gaussian white noise. It can enhance weak fundamental frequency components of...
Using the relationship between the number of zero-crossings and signal frequency, A Variable Bandwidth Band-pass Filter-Zero-Crossing Detection is proposed. This method can be used to estimate the echo frequency in Doppler Velocity Measurement. According to computer simulation, the estimation error of echo is 2 Hz approximately (Echo-to-Reverberation Ratio is -15 dB, echo frequency is 10360 Hz); according...
This is to report a simple one-step electrochemical deposition method for preparation of enzyme modified titanium-containing mesoporous molecular sieve TiSBA-15/chitosan (CHIT) composites on glassy carbon electrode (GCE) for biosensing. TiSBA-15/CHIT composites possessed excellent biocompatibility and led to the enclosed proteins in a well defined space remaining its bioactivity effectively. As a...
A new carrier of catalyst-Na2Ti3O7 whisker was selected and TiO2/Na2Ti3O7 was prepared by sol-gel method, then complex photocatalyst H3PW12O40/Na2Ti3O7 was prepared by dipping way. SEM photographs showed the production was covered well, TiO2 was anatase type and H3PW12O40 was Keggin structure. UV-vis RDS showed wavelength range unfolded red shifts. The photocatalytic activity of H3PW12O40/TiO2/Na2...
The photocatalyst of titanium dioxide/float pearls which had float performance was prepared by sol-gel method. The compound photocatalyst of phosphotungstic acid/titanium dioxide/float pearls which had high photocatalysis activity and floatability was prepared through surface modifying by dipping method. Scanning electron microscopy, X-ray diffraction and UV-Vis diffused reflectance spectroscopy analysis...
In order to investigate the effects of photocatalysis technique to the wastewater of dye, a new carrier of catalyst- micron attapulgite clay was selected. The TiO2/attapulgite clay photocatalyst was prepared by the sol-gel method. X-ray diffraction indicates that its diffracted peak of surface is same as the characteristic peak of TiO2. SEM pictures showed the form of sample is amorphous, and the...
A new carrier of catalyst was chosen. Sol-gel method was used to preparate TiO2/potassium titanate photocatalyst. EDS shows the main peck included Ti, O, K in potassium titanate whisker. The main peak of K disappeared and the peaks of Ti, O stayed after whisker was covered. It directed that the surface of sample was covered by TiO2. The figure of UV-vis diffuse reflection shows TiO2/potassium had...
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