A new glycosylation method. Part 2: Study of carbohydrate elongation onto the gold nanoparticles in a colloidal phase

A new reaction for carbohydrate elongation for synthesis of oligosaccharide using gold colloidal nanoparticles (GCNPs) has been developed. The gold core in this colloidal phase synthesis was prepared by a reduction of tetrachloroauric acid with 30,31-dithia-3,6,9,12,15,18,43,46,49,52,55,58-dodecaoxa-1,60-hexacontanediol. The presented alkanethionyl oligomeric ethylene glycol worked as a stabilizer of GCNPs and as a linker in chemical elongations of carbohydrates. This colloidal phase synthesis has several advantages such as (1) remnants of reagents and glycosyl donors in each reaction could be easily removed by ultrafiltration or gel filtration column chromatography, (2) further purifications are not required, and (3) the reactions can be monitored by MALDI-TOF MS directly without any pretreatment. In fact, we have successfully synthesized lactose derivative on GCNPs and will report these results in this paper.     

Development of 170 GHz/500 kW gyrotron

A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE_31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at P_RF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at P_RF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window.     

The logical quantization of algebraic groups

In a previous paper we introduced a highly abstract framework within which the theory of manuals initiated by Foulis and Randall is to be developed. The framework enabled us in a subsequent paper to quantize the notion of a set. Following these lines, this paper is devoted to quantizing algebraic groups viewed from Grothendieck's functorial standpoint.     

Optical array logic network computing: Design of a prototype system

We present the architecture of novel optoelectronic parallel computing called optical array logic network computing (OAL-NC). In the OAL-NC, electronic processing elements execute local operations, whereas an optical network processor is dedicated to global operations as well as data transfer. As a prototype of the OAL-NC, a 16x16 pixel system is designed at a logical level. Issues associated with the design task are discussed.     

High power 170 GHz test of CVD diamond for ECH window

In order to check the usability of large-size CVD (Chemical Vapor Deposition) diamond disks for high power millimeter wave vacuum barrier windows at room temperature (T = 293 K) a first series of experiments, using a 170 GHz, 0.4 MW, 0.2 s JAERI/Toshiba gyrotron¹⁾, have been performed. The dielectric loss tangent at a frequency of 170 GHz has been determined to be tan δ = 1.3·10⁻⁴. By comparing the experimental results to numerical simulations the thermal conductivity was estimated to be about k ≈ 1800 W/mK. This preliminary results indicate that a single-disk CVD diamond window assembly using a water-edge cooling could fulfill the requirements for a continuous wave (CW) transmission of millimeter wave power in the megawatt range. This is needed for the Electron Cyclotron Heating (ECH) on the International Thermonuclear Experimental Reactor (ITER).     

A novel class of materials for ferroelectric liquid crystals containing siloxy chain end groups

Novel liquid crystals containing a siloxy chain as an end tail group instead of an alkyl chain were synthesized. The substitution effects were studied for ferroelectric liquid crystal materials. It was found that the temperature range for the chiral smectic C phase was reduced and shifted to lower temperature in comparison with the analogous alkyl chain derivatives. The crystallinity of the siloxy chain derivatives decreased and cholesteric phases were not observed. The influence of siloxy chains on ferroelectric liquid crystal properties, especially spontaneous polarizations and tilt angles, also greatly depended upon the mesogenic group structure. The X-ray diffraction results showed that the end tail group occupied a larger thickness in the chiral smectic C layer for the siloxy chain derivative than that for the alkyl chain derivative.