A wave-induced stirring mechanism in the mid-depth equatorial ocean

A wave-induced stirring and transport mechanism for the mid-depth equatorial ocean is proposed and examined using both analytic linear equatorial wave solutions and a fully nonlinear reduced-gravity model. The study of kinematic stirring using the linear solutions suggests that a superimposition of a few simple equatorial waves can lead to strong Lagrangian stirring and transport along the equator. In particular, a combination of an annual long Rossby wave and a high-frequency Yanai wave appears to be most effective in producing strong stirring in the interior equatorial region. Further investigations of stirring properties using an inverted, fully nonlinear reduced gravity shallow-water model support the results of the kinematic stirring study. By evaluating the finite-time estimates of Lyapunov exponents, we identified two regions where chaotic stirring is most active. One is the western boundary region where short Rossby waves likely play a dominant role in producing the strong chaotic stirring. The other is the equatorial waveguide where a low-frequency Rossby wave prescribes the pattern of the stirring geometry, and a high-frequency Yanai wave plays a role of stirring the fluid. The proposed stirring mechanism provides a plausible explanation of the observed chlorofluorocarbon distribution found in the mid-depth equatorial Atlantic Ocean

Terephthalic acid–4,4′-bipyridine (2/1)

In the title compound, 2C8H6O4·C10H8N2, the 4,4′-bipyridine mol­ecule is located on an inversion centre. In the crystal structure, strong inter­molecular O—H⋯N hydrogen bonds between the terephthalic acid and 4,4′-bipyridine mol­ecules lead to the formation of chains with graph-set motif C 2 2(8) along the diagonal of the bc plane

catena-Poly[[bis­(p-toluene­sulfonato-κO)palladium(II)]bis­(μ-1,3-di-4-pyridylpropane-κ2 N:N′)]

In the title compound, [Pd(C7H7O3S)2(C13H14N2)2]n, the metal ion, located on a twofold rotation axis, exhibits a slightly distorted octa­hedral coordination environment, with bond angles that deviate by at most 2.2° from an ideal geometry, completed by two O atoms from two deprotonated p-toluene­sulfonic acid ligands and four N atoms from four 1,3-di-4-pyridylpropane ligands. One of the sulfonate O atoms is disordered over two positions [ratio 0.70 (5):0.30 (5)]

Monodisperse SiO2 Microspheres with Large Specific Surface Area: Preparation and Particle Size Control

Monodisperse SiO2 microspheres have found applications in catalysis, drug delivery, coatings, cosmetics, optical sensing and plastics. The particle size of monodisperse SiO2 microspheres is closely related to its application. In this paper, monodisperse SiO2 microspheres with tunable diameter were successfully synthesized using cetyltrimethylammonium bromide (CTAB) as template. The monodisperse SiO2 microspheres with diameters ranging from 200 nm to 3 μm were obtained by controlling the concentration of CTAB, tetraethyl orthosilicate (TEOS), diethanolamine (DEA) and reaction temperature. The BET surface area could reach 835 m2•g-1 and mean pore diameter was 2.3 nm. The formation mechanism of monodisperse SiO2 microspheres was investigated

The influence of local officials' promotion incentives on carbon emission in Yangtze River Delta, China

China's carbon emissions is heavily influenced by economic growth, which can be largely related to the local officials' promotion incentives. The current study was conducted to test the hypothesis that the influence of local officials' individual characteristics on carbon emissions was driven by the promotion incentives. Yangtze River Delta where carbon emissions accounted for around 13.95% of China's total emissions was selected as the research area. The multiple linear regression model was applied to determine the relationship between local officials' characteristics and total carbon emissions and carbon emissions from different sectors. The results indicated that local officials' promotion source, tenure and age significantly influenced the total carbon emission. Despite insignificance influence of officials' academic level on carbon emissions, the professional background in economics and management had a significant influence on carbon reduction. Our results indicated the importance of local officials' promotion incentives for carbon emission in China. Therefore, low carbon development should be included as an important part of official promotion system

Zirconium-Catalyzed Atom-Economical Synthesis of 1,1-Diborylalkanes from Terminal and Internal Alkenes

A general and atom-economical synthesis of 1,1-diborylalkanes from alkenes and a borane without the need for an additional H2 acceptor is reported for the first time. The key to our success is the use of an earth-abundant zirconium-based catalyst, which allows a balance of self-contradictory reactivities (dehydrogenative boration and hydroboration) to be achieved. Our method avoids using an excess amount of another alkene as an H2 acceptor, which was required in other reported systems. Furthermore, substrates such as simple long-chain aliphatic alkenes that did not react before also underwent 1,1-diboration in our system. Significantly, the unprecedented 1,1-diboration of internal alkenes enabled the preparation of 1,1-diborylalkanes. © 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA

Bis(ethano­lato-κO)(5,10,15,20-tetra­phenyl­calix[4]pyrrole)manganese(III) hexa­fluoro­phosphate

The title compound, [Mn(C2H5O)2(C44H28N4)]PF6, was synthesized from manganese(III) 2,4-penta­nedionate and 5,10,15,20-tetra­phenyl­calix[4]pyrrole by a hydro­thermal reaction. The MnIII atom is located on an inversion centre and the asymmetric unit comprises one half-formula unit. The MnIII ion is hexa­coordinated by four N atoms from one 5,10,15,20-tetra­phenyl­calix[4]pyrrole ligand and two O atoms from two deprotonated ethanol mol­ecules. The equatorially located atoms (the Mn and four N atoms) are planar. The dihedral angles between the planes of the phenyl rings and the equatorial plane are 53.3 (2) and 81.8 (2)°. One hexa­fluoro­phosphate anion balances the charge