A high frame-rate (HFR) imaging method (about 3750 frames/s for imaging of biological soft tissues at a depth of 200 mm) has been developed recently with limited diffraction beams. This method uses the fast Fourier transform (FFT) and inverse fast Fourier transform (IFFT) to construct images, and can be implemented with simple and inexpensive hardware, compared to the conventional delay-and-sum...

The fast adaptive composite grid (FAC) method is a systematic process for solving differential boundary value problems. FAC uses global and local uniform grids both to define the composite grid problem and to interact for its fast solution. It can with little added cost substantially improve accuracy of the coarse grid solution and is very suitable for vector and parallel computation. This pape...

We have developed a united atom (UA) nonpolarizable force field for 1-alkyl-3-methyl-imidazolium chloride ([C(n)mim][Cl], n = 1, 2, 4, 6, 8), a potential solvent for the pretreatment of lignocellulosic biomass. The charges were assigned by fitting the electrostatic potential surface (ESP) of the ion pair dimers. The Lennard-Jones parameters of the hydrogen atoms on the imidazolium ring were adj...

Fast spin-echo (FSE) pulse sequences enable T2-weighted imaging in a fraction of the time required for T2-weighted conventional spin-echo (CSE) imaging. Due to concerns that the altered contrast characteristics of FSE may interfere with the visualization of multiple sclerosis (MS) lesions, the sensitivity of T2-weighted FSE sequences was compared to comparably weighted CSE sequences in the imag...

Phosphatidylserine from human plasma was purified and identified by amino normal-phase and octadecylsilyl reversed-phase high-performance liquid chromatography, respectively. The two major molecular species within the human plasma phosphatidylserine, qualitatively determined by negative-ion fast atom bombardment mass spectrometry, are 1-stearoyl-2-oleoyl-sn-glycero-3-phosphoserine and 1-stearoy...

We report here the fabrication of freestanding HfO2 grating by combining fast atom beam etching (FAB) of HfO2 film with dry etching of silicon substrate. HfO2 film is deposited onto silicon substrate by electron beam evaporator. The grating patterns are then defined by electron beam lithography and transferred to HfO2 film by FAB etching. The silicon substrate beneath the HfO2 grating region is...

Fast neutrons are useful for activation analysis of several light elements. For example, oxygen analyses are routinely made in our reactor laboratory and elsewhere by the 160(n, p)]6N reaction. The threshold for this reaction is over 10 MeV. Napier et al. ~) have described a device which was intended to convert thermal neutrons into 14 MeV neutrons by the reaction sequence 6Li(n, o~)3H ... 2H(3...

The concept of amplitude-modulated multiplexed flow analysis has been extended to the simultaneous determination of multiple analytes in a sample. A sample solution containing nitrite and nitrate ions is delivered from two channels, but the flow rates are varied at different frequencies. One of the channels has a reduction column for converting nitrate ions to nitrite ions. Downstream, the abso...

Fast Fourier transform (FFT) simulation was used to calculate the power and spatial distribution of resonant fields in optical cavities. This is an important tool when characterizing the effect of imperfect geometry and mirror aberrations. This method is, however, intrinsically slow when the cavities are of relatively high finesse. When this is the case, an accelerated convergence scheme may be...