K-band high power latching switch

A 19 GHz waveguide latching switch with a bandwidth of 1400 MHz and an exceptionally low insertion loss of 0.25 dB was demonstrated. The RF and driver ferrites are separate structures and can be optimized individually. This analysis for each structure is separately detailed. Basically, the RF section features a dual turnstile junction. The circulator consists of a dielectric tube which contains two ferrite rods, and a dielectric spacer separating the ferrite parts along the center of symmetry of the waveguide to form two turnstiles. This subassembly is indexed and locked in the center of symmetry of a uniform junction of three waveguides by the metallic transformers installed in the top and bottom walls of the housing. The switching junction and its actuating circuitry met all RF performance objectives and all shock and vibration requirements with no physical damage or performance degradation. It exceeds thermal requirements by operating over a 100 C temperature range (-44 C to +56 C) and has a high power handling capability allowing up to 100 W of CW input power

The use of orbitals and full spectra to identify misalignment

In this paper, a SpectraQuest demonstrator is used to introduce misalignment in a rotating set-up. The vibrations caused by misalignment is measured with both accelerometers on the bearings and eddy current probes on the shaft itself. A comparison is made between the classical spectral analysis, orbitals and full spectra. Orbitals are used to explain the physical interpretation of the vibration caused by misalignment. Full spectra allow to distinguish unbalance from misalignment by looking at the forward and reversed phenomena. This analysis is done for different kinds of misalignment, couplings, excitation forces and combined machinery faults

Conceptual design of elliptical cavities for intensity and position sensitive beam measurements in storage rings

Position sensitive beam monitors are indispensable for the beam diagnostics in storage rings. Apart from their applications in the measurements of beam parameters, they can be used in non-destructive in-ring decay studies of radioactive ion beams as well as enhancing precision in the isochronous mass measurement technique. In this work, we introduce a novel approach based on cavities with elliptical cross-section, in order to compensate for existing limitations in ion storage rings. The design is aimed primarily for future heavy ion storage rings of the FAIR project. The conceptual design is discussed together with simulation results.Comment: Added definition of Uv and Pdiss in the introduction section. Added Mode numbering in table 1 and figure 1 for more clarity. Corrected one wrong figure reference. Other minor typo correction

Early development of the facial nerve in human embryos at stages 13–15

Study was made on 16 human embryos at developmental stages 13–15 (fifth week). The facial nerve was traced on serial sections made in three planes (sagittal, frontal and horizontal) and stained with routine histological methods and impregnated with silver. In embryos at stage 13 the facial ganglion forms a complex structure with the vestibulocochlear ganglion. It is of fusiform shape in contact with epipharyngeal placode and is located anteriorly and ventrally to the vestibulocochlear ganglion. In embryos at stage 14 the facial ganglion separates from the vestibular and cochlear ganglia and the chorda tympani as the first branch appears. During stage 15 the main trunk of the facial nerve elongates and the greater petrosal nerve originates at the level of the facial ganglion and above the origin of the chorda tympani

Transdermal uptake of diethyl phthalate and di(n-butyl) phthalate directly from air: Experimental verification

Background: Fundamental considerations indicate that, for certain phthalate esters, dermal absorption from air is an uptake pathway that is comparable to or larger than inhalation. Yet this pathway has not been experimentally evaluated and has been largely overlooked when assessing uptake of phthalate esters. Objectives: This study investigated transdermal uptake, directly from air, of diethyl phthalate (DEP) and di(n-butyl) phthalate (DnBP) in humans. Methods: In a series of experiments, six human participants were exposed for six hours in a chamber containing deliberately elevated air concentrations of DEP and DnBP. The participants either wore a hood and breathed air with phthalate concentrations substantially below those in the chamber or did not wear a hood and breathed chamber air. All urinations were collected from initiation of exposure until 54 hours later. Metabolites of DEP and DnBP were measured in these samples and extrapolated to parent phthalate intakes, corrected for background and hood air exposures. Results: For DEP the median dermal uptake directly from air was 4.0 µg/(µg/m3 in air) compared with an inhalation intake of 3.8 µg/(µg/m3 in air). For DnBP the median dermal uptake from air was 3.1 µg/(µg/m3 in air) compared with an inhalation intake of 3.9 µg/(µg/m3 in air). Conclusions: This study shows that dermal uptake directly from air can be a meaningful exposure pathway for DEP and DnBP. For other semivolatile organic compounds (SVOCs) whose molecular weight and Kow are in the appropriate range, direct absorption from air is also anticipated to be significant

Properties of neutron doped multicrystalline silicon for solar cells

The technology of neutron transmutation doping of silicon wafers in MARIA nuclear research reactor is described. The studies of the radiation defects performed with positron annihilation confirmed that divacancies dominate in the irradiated material. Thermal treatment of irradiated silicon at 700-1000°C produces void - phosphorus complexes and void aggregates. The resistivity of the samples produced by neutron transmutation doping was found to be uniform within 2.5% limits. The severe reduction of the minority carrier lifetime in irradiated samples was confirmed