Quasi-horizontal wave motions in the equatorial area are discussed. A single layer of homogeneous incompressible fluid with free surface is treated.The Coriolis parameter is assumed to be proportional to the latitude.In general, waves of two different types are obtained as solutions, one being the inertio-gravity wave and the other Rossby wave. They are distinguished from each other by the difference of frequencies and by the relationships between pressure and velocity fields.For the solutions of the lowest mode (waves confined near the equator), however, the distinction between the Rossby and the inertio-gravity waves is not clear. The wave moves westward and the frequency of this wave is compared to that of the gravity wave, if wave length is large.With the increase of the wave number the frequency decreases and approaches to that of the Rossby type wave. The pressure and wind fields of this wave show somewhat mixed character of the two types, and change continuously with the wave number. In this connection it seems impossible to "filter out" gravity waves from large scale motions.Another interesting feature of the equatorial disturbances is that the low frequency waves are trapped near the equator.It is shown that the both waves of inertio-gravity type and of the Rossby type have appreciable amplitude only near the equator.The characteristic north-south extent of the waves is (c/ ) 1/2, where c is the velocity of long gravity waves and is the Rossby parameter. This expression is identical with that derived by Bretherton (1964) for inertio-gravity oscillations in a meridional plane. In the later half, "forced stationary motion" in the equatorial region is treated.Based on the same model, mass sources and sinks are introduced periodically in the east-west direction.Then the motions and surface topography caused by them are calculated. As expected, high and low pressures appear where mass source and sink are given respectively.But these high and low cells are splitted into two parts separated by troughs or ridges located along the equator.Strong east-west current was formed along the equator. The flow directs from source to sink and it is intensified by the turning of the circular flow in the higher latitudes.

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A new type of ultra-high resolution atmospheric global circulation model is developed. The new model is designed to perform ''cloud resolving simulations'' by directly calculating deep convection and meso-scale circulations, which play key roles not only in the tropical circulations but in the global circulations of the atmosphere. Since cores of deep convection have a few km in horizontal size, they have not directly been resolved by existing atmospheric general circulation models (AGCMs). In order to drastically enhance horizontal resolution, a new framework of a global atmospheric model is required; we adopted nonhydrostatic governing equations and icosahedral grids to the new model, and call it Nonhydrostatic ICosahedral Atmospheric Model (NICAM). In this article, we review governing equations and numerical techniques employed, and present the results from the unique 3.5-km mesh global experiments-with O(10 9 ) computational nodesusing realistic topography and land/ocean surface thermal forcing. The results show realistic behaviors of multi-scale convective systems in the tropics, which have not been captured by AGCMs. We also argue future perspective of the roles of the new model in the next generation atmospheric sciences.

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Copper sees the light of day: [Cu(dap)(2)Cl] proved to be an excellent photoredox catalyst for atom-transfer radical addition reactions, as well as for allylation reactions (see scheme), providing an attractive alternative to commonly used iridium- and ruthenium-based catalysts.

Using a quasi one-dimensional model, in which the latitudinal distributions of variables are assumed and only the vertical dependence is explicitly treated, the general circulation of the middle atmosphere interacting with internal gravity waves is treated. An ensemble of internal gravity waves with an isotropic spectrum are introduced at the lower boundary and their propagation in the prevailing zonal wind field are determined incorporating the effect of eddy viscosity, in the same way as done by Plumb and McEwan (1978). As the result of selective transmission due to the background wind effect, deceleration of the stratomesospheric wind system and generation of a reverse flow take place near and above the mesopause level, owing to the wave momentum flux. Results of numerical calculations are compared with those obtained by using the conventional Rayleigh friction.

Belt-persistent tubular cycloarylenes possessing extended sp 2 -networks of finite single-wall carbon nanotubes (SWNT) have been synthesised from an abundantly available pigment possessing the dibenzo[def,mno]chrysene (anthanthrene) framework. The introduction of bulky substituents allowed for the diastereoselective production of a single helical isomer as a racemate, and the extension of the p-systems in the cycloarylene unexpectedly lowered the enthalpic barrier for the rotation of the arylene unit. Crystallographic analysis of the helical finite SWNT molecules revealed alternate layers of homohelical columns.

Twisted carbon nanobelts could display persistent chirality, which is desirable for material applications, but their synthesis is very challenging. Herein, we report the successful synthesis and chiral resolution of such a kind of molecules (1-H and 1) with a figure-eight configuration. 1-H was synthesized first by macrocyclization through Suzuki coupling reaction followed by benzannulation via Bi­(OTf)3-mediated cyclization reaction of vinyl ether. Oxidative dehydrogenation of 1-H gave the fully π-conjugated 1. Their twisted structures were confirmed by X-ray crystallographic analysis and calculations, and they can be resolved by chiral high-performance liquid chromatography. The isolated enantiomers showed persistent chiroptical properties according to the circular dichroism measurements, with moderate |g abs| values (0.0016 for 1-H and 0.005–0.007 for 1). Their photophysical properties were also briefly studied.