Theoretical study of valence photoelectron spectra of Re(CO)5X (X=Cl, Br, and I): a spin-orbit DK3 symmetry-adapted cluster/symmetry-adapted cluster-configuration interaction study

The valence photoelectron spectra of Re(CO)(5)X (X=Cl, Br, and I) are studied theoretically using symmetry-adapted cluster (SAC)/SAC-configuration interaction (SAC-CI) theory. The relativistic effects are included by the third-order Douglas-Kroll (DK3) method, and the spin-orbit coupling is also considered. Both electron correlation and relativistic effects are significant in assigning the valence photoelectron spectra of Re(CO)(5)X (X=Cl, Br, and I). DK3-SAC/SAC-CI provides values for the relative peak positions in a reasonable agreement with the observed photoelectron spectra. The sequence of ionization energies for Re(CO)(5)Cl, Re(CO)(5)Br, and Re(CO)(5)I are calculated as e(')[a(1)(Cl)]>e(')[e(Re+Cl)] approximately e(")[e(Re+Cl)]>e(")[b(2)(Re)]>e(')[e(Re-Cl)]>e(")[e(Re-Cl)], e(')[a(1)(Br)]>e(')[e(Re+Br)]>e(")[e(Re+Br)+b(2)(Re)]>e(")[b(2)(Re)+e(Re+Br)]>e(')[e(Re-Br)]>e(")[e(Re-Br)], and e(')[e(Re+I)+a(1)(I)]>e(")[b(2)(Re)+e(Re+I)] approximately e(')[a(1)(I)+e(Re+I)]>e(")[e(Re+I)+b(2)(Re)]>e(')[e(Re-I)]>e(")[e(Re-I)], respectively. These assignments are quite new and different from previous assignments.     

Cyclodextrin-Based Contrast Agents for Medical Imaging

Cyclodextrins (CDs) are naturally occurring cyclic oligosaccharides consisting of multiple glucose subunits. CDs are widely used in host–guest chemistry and biochemistry due to their structural advantages, biocompatibility, and ability to form inclusion complexes. Recently, CDs have become of high interest in the field of medical imaging as a potential scaffold for the development of a large variety of the contrast agents suitable for magnetic resonance imaging, ultrasound imaging, photoacoustic imaging, positron emission tomography, single photon emission computed tomography, and computed tomography. The aim of this review is to summarize and highlight the achievements in the field of cyclodextrin-based contrast agents for medical imaging.     

Optical transfer function analysis of Lau-Type grating atom interferometer

A grating interferometer composed of two transmission gratings in tandem irradiated incoherently was studied for an atom interferometer. Determination of its interference effect was made with consideration of the optical transfer function. An atom beam had a velocity distribution, which made the influence on the interference phenomenon. The calculated results show that the fringe (grating image) with relatively high contrast is obtained under a certain grating arrangement even if the interferometer is irradiated by a spatially incoherent polychromatic atom beam.     

Micro fluorescent analysis system integrating GaN-light-emitting-diode on a silicon platform

A micro fluorescent analysis system is proposed using silicon micromachining. GaN blue light-emitting diode (LED) monolithically integrated on a silicon substrate is used as a light source for the fluorescent analysis system. The blue light suits the excitation of several dyes used commonly in fluorescent analysis. Silicon photodiode (Si-PD) that matches the visible and near infrared fluorescent wavelengths of dyes is integrated on a silicon substrate. Polydimethylsiloxane (PDMS) micro-channels are also stacked for flowing dye-sensitized liquid. Therefore, the proposed system is an integrated system that can be composed on a silicon platform, i.e. a bottom layer of Si-PD, a middle layer of GaN-LED on silicon substrate and a top layer of micro PDMS channel. An aperture is opened into the GaN-LED layer by deep reactive ion etching to create a ring-shaped GaN-LED and a through-hole for detection. The light from the ring-shaped GaN-LED in the middle layer excites the dye-sensitized liquid in the top micro-channel layer. The fluorescence emitted from dye is detected by the Si-PD on the bottom layer at an angle larger than 90 degrees from the direction of excitation. Therefore, the detection optics consist basically of a dark-field illumination optical system. In order to evaluate the performance of the integrated system, fluorescence of fluorescein isothiocyanate (FITC) solution flowing in the micro channel is measured. From the measurement, the noise, sensitivity and limit of detection in the fabricated system are evaluated for FITC dye to be 0.57 pA, 1.21 pA μM(-1) and 469 nM, respectively. From these results, a compact fluorescence analysis system is demonstrated.     

Moiré displacement measurement technique for a linear encoder

The light intensity diffracted from superimposed dual transmission gratings is sensitive to their relative lateral displacement but is also affected by changes in the air gap between them. Averaging the diffracted light intensities obtained in the gap range of a Fourier image distance, the resultant intensity was almost independent of the gap between the two gratings and had a period of half the pitch of the grating for the lateral displacement. This method can be used for a linear encoder in precision machining.     

Tilt-insensitive film thickness measurement using a double twin-path interferometer

A lock-in amplifier detection method for measuring the film thickness on a flat substrate has been developed by using a common-path interferometer. The signal due to the film thickness has been obtained without it being affected by the tilting of the substrate. The sensitivity was better than 0.5 nm.     

Determination of the immunosuppressive drug tacrolimus in its dosage forms by high-performance liquid chromatography

Summary A high-performance liquid chromatographic (HPLC) method has been developed and validated for the determination of FK506, a new immunosuppressant, in bulk drug samples and dosage forms. Equilibration between FK506 (I) and its tautomeric compounds (II and III) was accomplished artificially in water-dehydrated alcohol (11) employed as an extraction solvent. After reaching equilibrium, separation of I, treated as the representetive of equilibrated FK506, from its related substances was achieved by reversed-phase HPLC on a C₁₈ column with water-isopropyl alcohol-tetrahydrofuran (522, v/v) as the mobile phase, and detection at 220 nm. Component I in dosage forms could be recovered satisfactorily and determined with good precision. The calibration graph was linear over the range 2–6 g for I.     

Electric feed-through for vacuum package using double-side anodic bonding of silicon-on-insulator wafer

It is not easy to hermetically seal using anodic bonding on both sides of silicon-on-insulator (SOI) wafer. Taking this into consideration, we suggest an electrical feed-through method for anodic bonding on the both sides of SOI wafer. The suggested method is illustrated on the basis of vacuum package of a conventional two-dimensional (2-D) micro-scanner. Electric feed-through for anodic bonding and electrical interconnection through the glass/silicon interface to the 2-D micro-scanner in the package are presented. The proposed electrical feed-through method is investigated by characterizing bonding current. The bonding current characteristics show that the electric feed-through has formed electric field distribution required for double-side anodic bonding. The operation characteristics of packaged 2-D micro-scanner are also investigated, which show successfully performed electric interconnection between inside and outside of the package. The proposed method is an effective technique for double-side anodic bonding based package not only for micro-scanner but also for different mechanical oscillators such as accelerometer, gyroscope and etc.     

A two-dimensional self-aligning system driven by shape memory alloy actuators

The two-dimensional automatic alignment system with an optical aperture is developed. The optical aperture with four integrated photodiode cells for feedback control signal is fabricated by MEMS techniques. The translation stage of the system is driven by four shape-memory-alloy positioning actuators to realize two-dimensional (XY-plane) movement.     

Sequencing inputs to multi-commodity pipelines

This paper examines the problem of sequencing the input of commodities, e.g. petroleum products, to a pipeline so that a surrogate for pumping and maintenance costs is minimized. This problem is complicated by the need to impose a discrete framework which handles the sequencing choices on a continuous flow problem. By focusing on the discrete aspects of the problem, the proposed model allows decomposition of the sequencing problem into subproblems which can be easily priced out in a branch-and-bound algorithm. Computational results on data generated to mimic a large U.S. petroleum pipeline are presented. These results show that the branch-and-bound algorithm only explores a small region of the solution space within a reasonable amount of time, less than 2.5 minutes to optimally sequence deliveries to twenty-four destinations.