Preparation of homo- and co-dimers of styrene derivatives using phosphate

Summary Dimers were preferably obtained in the oligomerization of styrene derivatives by diphenyl hydrogen phosphate. The reaction was assumed to proceed through the formation of esters from the monomers and diphenyl hydrogen phosphate as intermediate. This assumption was confirmed by the fact that treatment of the esters with alternative styrene derivatives gave linear codimers.     

Novel vector control system using deadbeat-controlled PWM inverter with output LC filter

This paper proposes a novel high-performance vector control system of an ac motor using a low-switching-frequency (2 kHz) pulsewidth-modulation voltage-source inverter with an output LC filter. Excellent high-speed response characteristics of the LC filter output voltage have been realized using a novel deadbeat control algorithm. As for the experimental results, the torque current response that is similar to the response of the conventional system without an LC filter has been obtained. In addition, it has been confirmed by simulation that errors of the LC filter constants within /spl plusmn/10% can be permitted.     

Scanning limitation in adaptive superresolution array

A fundamental limitation in an adaptive superresolution array, due to reciprocity between the angular resolution capability and the measurement time required, is discussed. For this purpose, a new concept for the measurement time, a scanning time concept, is introduced by considering a superresolution array consisting of an Applebaum-Howells adaptive processor with steering signal changing periodically with time. The measurement time is defined as the amount of time taken to perform one observation over the range of desired angle. Superresolution array output is defined according to the adapted angular response formulation. It is shown that the relationship between the resolution capability and the scanning time is reciprocal, i.e., the increased angular resolution is obtained at the expense of the scanning time. The relationship is discussed quantitatively for a narrow-band signal model.     

Ring-opening copolymerization of 2,4-bisphenyl-1,3,2,4-dioxadiphosphetane-2,4-dioxide with oxetane via zwitterion intermediates

Summary Copolymerization of 2,4-bisphenyl-1,3,2,4-dioxadiphosphetane-2,4-dioxide (DPO) with oxetane, a cyclic ether, was found to take place at 90 and 120°C without initiator. Copolymers obtained have a structure of phosphonate-ether units (1), which was determined by ³¹P, ¹H and ¹³C NMR, IR and elemental analysis. Oxetane was incorporated into 1 in a slight excess in all runs(m value in 1=1.5–2.1). A small amount(<15%) of a by-product (2) was always formed. Other cyclic ethers such as ethylene oxide and propylene oxide did not afford copolymers but gave 11 addition products, 10 and 11, quantitatively. The copolymerization is reasonably explained by a mechanism in which DPO behaves as an electrophilic monomer and oxetane as a nuicleophilic one. A pyrophosphonate species is considered to be a key intermediate to lead to copolymer 1 and the whole reaction course is discussed in detail.     

Stiffness and damping coefficients of spherical spiral grooved bearings: Influences of vertical eccentricity and compressibility of lubricant

The dynamic characteristics of a spherical spiral groove bearing have been analysed using a narrow groove hypothesis for the cases of incompressible fluid film and isothermal gas film. The usefulness of the proposed method is demonstrated by a comparison of results with those obtained using established methods. The method is especially efficient for optimization design and other analysis problems for which other available calculation methods require significant computational effort. The influence of bearing parameters and compressibility of the fluid on dynamic performance and stability are presented.     

A logical basis for programming methodology

In this paper, the relation between WHILE-programs and formal proofs of their quantified specification is studied. This gives us a logical basis for programming methodology since the programming concepts such as assignment statements, IF-statements and WHILE-statements are fully explained logically, here ‘logically’ means ‘how to think’. As an example, Hoare's program FIND is studied methodologically.     

Reclamation of vulcanized rubbers by chemical degradation. VIII. Absorption of oxygen and degradation of cis-1,4-polyisoprene by phenylhydrazine–iron(II) chloride system

Absorption of oxygen and degradation of cis-1,4-polyisoprene by the phenylhydrazine–iron(II) chloride system was investigated at 30°C in connection with the mechanism of reclamation of vulcanized rubbers by the system. In the presence of iron(II) chloride, phenylhydrazine rapidly absorbed an equimolar amount of oxygen and evolved an equimolar amount of nitrogen. Gas-chromatographic analysis of the reaction mixture showed the presence of benzene, phenol, and biphenyl in 37%, 35–60%, and 4–8% yields, respectively, based on phenylhydrazine. When cis-1,4-polyisoprene was added to the reaction mixture, additional absorption of oxygen was observed. Molecular weight of the polymer decreased during the oxygen absorption, and the scission efficiency (i.e., number of mole scissions/mole oxygen) was 0.14–0.26.     

Production and characterization of recombinant tachycitin, the Cys-rich chitin-binding protein

Tachycitin is an invertebrate chitin-binding protein with anamidated C-terminus, and possesses antimicrobial activity againstboth fungi and bacteria. The ¹H-NMR-based tertiary structureof tachycitin was recently determined [Suetake et al. (2000)J. Biol. Chem., 275, 17929–17932]. In order to examinethe structural and functional features of tachycitin more closely,we performed for the first time, gene expression, refolding,¹⁵N-NMR-based characterizations, and antimicrobial activitymeasurements of a recombinant tachycitin (rTcn) that does nothave the amide group at the C-terminus. The NMR analysis indicatedthat rTcn possesses the same structural construction as thenative tachycitin. The backbone ¹⁵N relaxation measurementsshowed that the molecular motional correlation time of rTcnincreases as its concentration increases, indicating that tachycitinshave a tendency to aggregate with each other. rTcn exhibitsantimicrobial activity against fungi but not against bacteria.The cell surface of fungi contains chitin as an essential constituent,but that of bacteria does not. These results suggest that notonly the chitin-binding region but also the C-terminal amidegroup of tachycitin plays a significant role in its antimicrobialproperties.     

Severe pneumococcal pneumonia with acute respiratory failure and neutropenia

A biological bank has been developed to extend the biochemical and molecular research base for a prospective study on diet and cancer in the city of Malmo, Sweden. The study entered individuals 45-69 years of age, of which 30,382 individuals (45%) participated. Each individual entering the bank has stored samples of viable mononuclear leukocytes (MNLs; -140 degrees C) and granulocytes (GRANs; -80 degrees C) or buffy coats (-140 degrees C), erythrocytes (-80 degrees C), and plasma/serum (-80 degrees C). The bioassays developed to monitor the quality of storage conditions were: (a) viability and growth response to phytohemagglutinin for MNLs; (b) DNA strand breakage for GRANs; (c) NAD content for erythrocytes; and (d) thiol status for plasma/serum. The yield, purity, and storage conditions were all quality controlled, and the samples were determined to be of high standard after 137-190 weeks of storage. No differences in yield and purity were found in samples banked by different laboratory technicians. Growth responses of MNLs were severely reduced (90%) after 40 weeks of storage, which justified switching from the storage of purified MNLs and GRANs to the more cost-effective banking of buffy coats. We conclude that the quality of the banked material, based on the biochemical analysis done, indicate that the storage conditions are optimal at least up to 3.5 years, except for the growth response of MNLs.     

Detection of object under outdoor environment by matching with partial and whole templates

This paper proposes the technique of augmented template matching that positions the object having a standard shape of two dimensions under the outdoor environment. The intensity of the object under the outdoor environment usually changes in various ways. The main reason is that the lighting condition changes, and the surface properties of the object change. It is difficult to apply the conventional template matching under the outdoor environment, because conventional template matching assumes the lighting condition does not change and the surface properties of the object do not change. Then, the partial template made by dividing the conventional template (the whole template) to increase information on the object to discriminate the object under the outdoor environment is introduced. The proposed technique is to calculate similarities with the partial and the whole templates, and to judge by the linear discriminant method. In this paper, the principle of the proposed technique and effectiveness based on the experimental result are shown. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 154(4): 49–60, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20270