Novel diblock copolymers based on poly(isobutyl methacrylate) (PiBMA) and poly[2,5di(isopropyloxycarbonyl)styrene] (PiPCS) were designed and prepared via consecutive atom transfer radical polymerization. They had relatively low molecular weight distributions and tunable molecular weights. The molecular characterization of the copolymers was performed with proton nuclear magnetic resonance spect...

Introduction Echo-planar imaging (EPI) is a group of fast data acquisition methods commonly used in fMRI studies. It acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. A well-known problem with EPI is that it is more sensitive to distortions due to the used encoding scheme. Source of distortion is inhomogeneity in the static B0 field that ...

The effect of geometrical asymmetry β (described by the length-diameter ratio of rods) on the rod-coil diblock copolymer phase behavior is studied by implementation of self-consistent field theory (SCFT) in three-dimensional (3D) position space while considering the rod orientation on the spherical surface. The phase diagrams at different geometrical asymmetry show that the aspect ratio of rods...

the aim of this paper is to minimize output phase noise for the pure signal synthesis in the frequency synthesizers. for this purpose, first, an exact mathematical model of phase locked loop (pll) based frequency synthesizer is described and analyzed. then, an exact closed-form formula in terms of synthesizer bandwidth and total output phase noise is extracted. based on this formula, the phase ...

PURPOSE To develop a simple method for combining phase images from multichannel coils that does not require a reference coil and does not entail phase unwrapping, fitting or iterative procedures. THEORY AND METHODS At very short echo time, the phase measured with each coil of an array approximates to the phase offset to which the image from that coil is subject. Subtracting this information f...

The Raman spectrum of cyclosporin-A has been recorded in the solid phase. The conformation of the molecule has been discussed on the basis of Raman data. It has been concluded that in agreement with X-ray data, cyclosporin-A molecule has an antiparallel P- pleated sheet conformation. It may have some reverse P- turn structure in what has been assigned to a random coil conformation.

Phase imaging benefits from strong susceptibility effects at very high field and the high signal-to-noise ratio (SNR) afforded by multi-channel coils. Combining the information from coils is not trivial, however, as the phase that originates in local field effects (the source of interesting contrast) is modified by the inhomogeneous sensitivity of each coil. This has historically been addressed...

introduction echo-planar imaging (epi) is a group of fast data acquisition methods commonly used in fmri studies. it acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. a well-known problem with epi is that it is more sensitive to distortions due to the used encoding scheme. source of distortion is inhomogeneity in the static b0 field that ...

rotating machines in particular induction electrical machines are important industry instruments. in manufacturing, electrical motors are exposed to many damages, and this causes stators and rotors not to work correctly. in this paper we addressed modal analysis and an intelligent method to detect motor load condition and also the stator faults such as turn-to-turn and coil-to-coil faults using...

Introduction & Purpose: Multi-channel phased-array radio-frequency (RF) coils are capable of acquiring several streams of acquisitions in parallel, resulting in improved signal-to-noise ratios (SNR) and faster scan times (1,2). Data streams from these coils must be added in-phase during coil combination or risk losing signal to phase cancellation. Conventional coil combination schemes work well...