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The development of robust and reactive chiral catalysts is a fundamental aim in asymmetric catalysis, and crucial for providing efficient methods for synthesizing chiral molecules. Chiral paddle-wheel bimetallic complexes provide a highly tunable chiral environment in rhodium-catalysed asymmetric carbene/nitrene transfer reactions and Lewis acid-catalysed reactions. Chiral paddle-wheel complexes having other transition metals as the reactive metal centre, however, have not yet been identified in asymmetric catalysis. Here, we report the synthesis, structures and high catalytic performances of chiral paddle-wheel diruthenium complexes. The cationic chiral diruthenium complex [Ru2((S)-BPTPI)4]+ exhibited remarkable reactivity as a Lewis acid catalyst for asymmetric hetero-Diels–Alder reactions, achieving a turnover number of up to 1,880,000 with high enantioselectivity (>90% e.e.). The chiral diruthenium complexes also exhibited good reactivity and high enantioselectivity in C–H amination and cyclopropanation reactions under oxidizing conditions, indicating their high tolerance towards oxidation. Our results reveal the chiral paddle-wheel diruthenium scaffold as a promising platform for asymmetric catalysis. The development of chiral catalysts is of fundamental importance in asymmetric catalysis. Now, chiral paddle-wheel diruthenium complexes are reported that are stable under oxidizing conditions and effective in asymmetric C–C and C–N bond-forming reactions with turnover numbers of up to 1,880,000.

Despite their unique potential as rare 1,1-dipole synthons, allyl sulfones are rarely used in target-oriented syntheses, likely due to the lack of a general catalytic method for their branch-selective allylic substitution. Herein, we identified allyl 4-chlorophenyl sulfone as a versatile linchpin for both base-mediated α-derivatization and subsequent cobalt-catalyzed allylic substitution. The sequential transformations allow for highly regioselective access to branched allylic substitution products with a variety of aliphatic side chains. The photoredox-enabled­ ­cobalt catalysis is indispensable for achieving high yields and regioselectivity­ for the desulfonylative substitution in contrast to traditional metal-catalyzed protocols, which lead to inferior outcomes in the corresponding transformations.

Co-catalyzed allylic substitution reactions have received little attention, arguably because of the lack of any known advantage of Co catalysis over either Rh or Ir catalysis. Described here is a general and regioselective Co-catalyzed allylic alkylation using an in situ catalyst activation by organophotoredox catalysis. This noble-metal-free catalytic system exhibits unprecedentedly high reactivities and regioselectivities for the allylation with an allyl sulfone, for the first time, representing the unique synthetic utility of the Co-catalyzed method compared to the related Rh- and Ir-catalyzed reactions.

Urinary steroid hormones and luteinizing hormone (LH) were monitored in a female pileated gibbon. The LH concentration almost peaked the day after estrogens peaks. The progesterone increased sharply after the LH peaks. Our results revealed for the first time the relationship between daily changes in urinary hormones throughout normal menstrual cycles in pileated gibbon.

The Van Veen loop is intrinsically well adapted to time-domain measurements of net magnetic dipole moment. That is, the system comes very close to preserving the shape of the time-domain waveform of the net or residual magnetic dipole moment produced by the DUT. This property makes the Van Veen Loop very useful in the characterization of magnetic field wireless power transfer systems in which short-time-scale features such as ringing in inverter and rectifier circuits are present in the extraneous magnetic field. We present two modifications to the internal circuitry which further improve the time-domain performance of the system to the extent that it approaches having a distortionless transfer function. Finally, we present a physical explanation for the mechanism by which the time-domain performance is improved.

Magnetic Field Wireless Power Transfer (MF-WPT) is appropriate for high-power applications such as the charging of electric vehicle batteries. Most systems operate essentially as resonant converters with the couplers (primary and secondary windings) and matching networks absorbed into the tank circuit of a resonant converter topology. As in a well-designed resonant converter, the currents in the couplers are quasi-sinusoidal. The extraneous electromagnetic field of such a system viewed in the frequency domain naturally includes a strong contribution at the fundamental frequency. However, it also necessarily includes components due to rectifier harmonics and short-time-scale ringing both in the inverter and rectifier circuits. We examine the relationship between the primary and secondary coupler currents and the extraneous electromagnetic field. It is seen that the electromagnetic field at some distance from the system has a spectral character markedly different from that of the primary and secondary currents. This is due to the fact that the induction and radiation fields of magnetic multipoles (predominantly dipole and quadrupole) depend not only on the associated magnetic moments but also on frequency. While the static fields depend directly on moment which, in turn, depends on current magnitude, the quasi-static induction and the radiation fields depend on the product of moment and a non-zero power of frequency.

When a large-size car exists on the ETC lane (Electronic Toll Collection System), there is the possibility that the interference on the adjacent lane occurs by the scattering waves from one. In this paper, we propose a new improvement method which the transparent EM wave absorber is placed between the ETC lane and the adjacent one in order to suppress the scattering waves from a large-size car. Therefore, we design the transparent EM wave absorber which consists of the transparent resistive and conductive films. Then, this absorber is produced, and its reflection and transmission coefficients are evaluated. In addition, its transmittance in optics is evaluated. As the results, the reflectivity of this absorber is obtained lower than -20dB in the oblique incident angle from 0° to 30 at 5.8 GHz circular polarized wave, abbreviated as CP wave, and also the transmittivity is obtain lower than -27 dB in the oblique incident angle from 0° to 70°, respectively. On the other hand, the transmittance in optics is obtained higher than 60%. Moreover, we study experimentally on the ETC system with placing this absorber between the ETC lane and the adjacent one. We measured the distribution of receiving power on the adjacent lane, when a water sprinkler existed on the ETC lane. As a result, it is confirmed that the receiving power on the adjacent lane could be realized lower than -70.5 dBm, and then a new improvement method has proven to be very useful in the ETC system.

It is important to grasp the reflectivity of EM wave absorbers in millimeter waves by rapid progress in a recent utilization of the frequency. A Free Space Method with horn antennas is in widespread use for the reflectivity evaluation of EM wave absorbers. In this paper, we investigate a Free Space Method that can evaluate accurately the reflectivity of EM absorbers in millimeter waves. We present the fundamental data and conditions for a Free Space Method to evaluate accurately the reflectivity of EM absorbers in millimeter wave. Moreover, the reflectivity of dielectric materials (e.g., quartz glass, single crystal sapphire) with a uniform constant is measured. As a result, the validity of a Free Space Method in millimeter waves is confirmed by comparing the evaluated characteristics of dielectric materials to a theoretical value.

Practical implementations of the Van Veen Loop, or Large Loop Antenna (LLA), necessarily contain imperfections, especially those due to finite mechanical tolerances. We examine the effects on performance of non-commensurate constituent transmission lines and unequal terminating resistors in the internal network of an LLA. It is shown that the electric field rejection of the LLA is somewhat insensitive to these errors, especially in the lower portion of its operating frequency range. Unfortunately, it is also shown that the effects of these two imperfections on the validation factor are very similar to one another and to those caused by an imperfect current transformer. Thus, for a practical LLA, it can be difficult to trace the source of the deviation of the validation factor from the ideal behavior. Suggestions are given for minimizing the effects of asymmetry in the practical LLA thereby enhancing the electric field rejection.

N-シアノアミジンは一般にアルカリに対して不安定であるが,芳香族のN-シアノベンズアミジン類5は比較的安定で,低温でアルカリ存在下に二硫化炭素を作用すると,N-(N-シアノベンズイミドイル)イミドジチオ炭酸塩12を生じ,このものは酸性下で環化して,最終的に6-アミノ-4-アリール-2H-1,3,5-チアジアジン-2-チオン類6を生成した。6をアルカリで処理すると転位が進行し,6-アリール-1,3,5-トリアジン-2,4-ジチオール11を,また酸加水分解ではチアジアジン環の4位が選択的に攻撃を受けてN-ベンゾイルチオ尿素15を与えた。また,6とアミンとの反応も同様に4位で進行し,N-チオカルバモイルベンズアミジン19を生成した。一方,求電子試薬であるヨウ化メチルをアルカリ存在下に作用させると,2,4-ビス(メチルチオ)-6-アリール-1,3,5-トリアジン類21を与えた。

We present a realization of a transparent wave absorber effective for use at V-band frequency. First, we propose a structure of the transparent wave absorber consisting of spacer (polycarbonate) and two transparent resistive sheets (polyethylene-terephthalate deposited with indium-tin-oxide) used as reflection and absorption films. Second, a design chart for this type of wave absorber is shown. Third, a design method and manufacturing process of the transparent wave absorber are described, particularly for V-band frequency. As a result, the measurement of reflection loss of the absorber indicates that a peak absorption of 32-38 dB is attained at a target frequency of 60 GHz.

This study intends to search for obvious criteria for all involvement in the process of revising the rule in artistic gymnastics. As a starting point, this study probed the Theory of Adaptablity by Talcott Parsons, which was ieading to a philosophical interpretation of the theory. Why has this study entered the field of Sociology in search for the criteria? It is because sports activities are part of our social activities. And Sociology, as a precondition, is one of the basic foundations of Sports Science. The four elements required to sustain the social system, according to Parsons, are pattern-maintenance, integration, goal-attainment and adaptation all of which must continue to function.When the four elements are introduced into artistic gymnastics, they will become as follows: Pattern-maintenance: Training activities and study meetings for coaches and judges. Integration: It denotes the various rules in artistic gymnastics. Goal-attainment: It refers to such governing bodies as the FIG and national federations. And Adaptation means various competitions.As a result, it has become obvious that revision of gymnastic rules became inevitable to avoid confusion in scoring due to anachronistic difference in technical levels and interpretation of artistic gymnastics on a global scale. Thus, revision of rules becomes necessary to solve all those issues. Furthermore, it also meant that revisions were effective measures to solve various global problems.However, as the revised rules were once not adopted by whole world and became meaningless, it had taught a great lesson to all those concerned. Therefore, all those engaged in the process of revising the rules must fully realise that they should draft rules that are adaptable to the fast maving world of today.

It is known that a reflected wave from an electromagnetic wave absorber on a wall of an anechoic chamber includes higher-mode diffracted waves. Our research group has studied higher mode diffracted waves from pyramidal wave absorber by measurements and simulations. Meanwhile, an evaluation method for anechoic chambers is defined by the CISPR16-1-4 Ed.3 standard. In this method, measured site voltage standing wave ratios (SVSWR) are affected by several factors such as frequency step, antenna directivity, and boundary between wave absorber and floor. There are several reports about measurement results of anechoic chambers where SVSWR values showed higher values at the specific frequencies. In these reports, the authors suspected that these high SVSWR values were caused by antenna directivity or characteristics of wave absorbers. However the actual reason has not been found out. We supposed higher mode diffracted waves affect SVSWR measurements. In this report, we calculated higher mode diffraction coefficients for pyramidal wave absorber using FDTD. And we simulated a SVSWR measurement by using these higher mode coefficients. In the results, we observed that SVSWRs went up sharply higher at specific frequencies as seen in actual measurements.

This paper presents two tunable notch filters (TNFs) for detect-and-avoid (DAA) implementation in an ultra-wideband (UWB) radio system. The developed filters have relatively wide- and narrow-stopband, respectively, using two different resonant structures. A system experiment has been carried out to evaluate the influence of bandwidth of notch band on the system performance when the two different filters are implemented for the DAA. The UWB system used in the evaluation is a multi-band OFDM-based system. The experimental results clearly show the different influences with different bandwidth of notch band on the system performance both from the signal spectrum and throughput of the data transmission. The narrow band tunable notch filter improves receiving sensitivity by about 3 dB compared with the wide band filter.

The authors have succeeded in manufacturing a transparent wave absorber consisting of a spacer and two transparent resistive sheets for operation at V-band. Measured frequency characteristics of the reflection loss indicate that a peak absorption of 35-38 dB is attained at a target frequency of 60 GHz.

In this paper, radiation patterns of a small loop antenna (l

We have succeeded to manufacture the transparent wave absorber consisting of spacer and two transparent resistive sheet for V-band frequency. Measured frequency characteristics of the reflection loss indicate that a peak absorption of 35-38dB is attained at a target frequency of 60GHz.