Invariant Measures and Lower Ricci Curvature Bounds

Potential Analysis - Given a metric measure space $(X,d,\mathfrak {m})$ that satisfies the Riemannian Curvature Dimension condition, RCD?(K,N), and a compact subgroup of isometries G ≤...     

Phosphorescent κ3-(N^C^C)-Gold(III) Complexes: Synthesis,Photophysics, Computational Studies and Application to Solution-Processable OLEDs

Efficient OLED devices have been fabricated using organometallic complexes of platinum group metals. Still, the high material cost and low stability represent central challenges for their application in commercial display technologies. Based on its innate stability, gold(III) complexes are emerging as promising candidates for high-performance OLEDs. Here, a series of alkynyl-, N-heterocyclic carbene (NHC)- and aryl-gold(III) complexes stabilized by a κ³-(N^C^C) template have been prepared and their photophysical properties have been characterized in detail. These compounds exhibit good photoluminescence quantum efficiency (η_PL) of up to 33 %. The PL emission can be tuned from sky-blue to yellowish green colors by variations on both the ancillary ligands as well as on the pincer template. Further, solution-processable OLED devices based on some of these complexes display remarkable emissive properties (η_CE 46.6 cd.A⁻¹ and η_ext 14.0 %), thus showcasing the potential of these motifs for the low-cost fabrication of display and illumination technologies.     

John’s Ellipsoid and the Integral Ratio of a Log-Concave Function

We extend the notion of John’s ellipsoid to the setting of integrable log-concave functions. This will allow us to define the integral ratio of a log-concave function, which will extend the notion of volume ratio, and we will find the log-concave function maximizing the integral ratio. A reverse functional affine isoperimetric inequality will be given, written in terms of this integral ratio. This can be viewed as a stability version of the functional affine isoperimetric inequality.     

Synthesis of EDTA core dendrimers through a consecutive esterification-CuAAC process

A novel class of thermostable G0 and G1-dendrimers was synthesized from the coupling of both propargyl and azido esters derived from EDTA through copper catalyzed azide-alkyne cycloaddition. The branching and size in these compounds were controlled by a simple azide-alkyne group position change in the CuAAC reaction in conjunction with the use of 1,3-diazido-propan-2-ol as a polyfunctional compound.     

Substituent Effects on 31P NMR Chemical Shifts and 1JP–Se of triarylselenophosphates

The effect of electron-withdrawing (EW) and electron-releasing (ER) substituents on the ³¹P NMR chemical shifts and the structural parameters of a series of tris-(p-X-aryl)selenophosphates is reported in this article. Similarly to O-aryl phosphates and O-aryl thiophosphates, EW groups attached to aromatic rings induce a shielding effect on the ³¹P NMR signal. After a detailed experimental and theoretical analysis, we confirmed that the selenium atom is the main part responsible for the charge density transfer toward phosphorus through a back-bonding effect. The obtained ¹J_P-Se values for the complete series agree with this observation.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Activation energies and structural changes in carbon nanotubes during different acid treatments

In this work, we studied the effect of acid type in the final properties of CNTs as the resistance to air oxidation; for this, different techniques of characterization were used such as Raman spectroscopy, thermogravimetric analysis, and chemical analysis by ICP-AES. Through Raman spectroscopy, it is possible to monitor the structural changes induced by acids and this is reflected in changing of the activation energies for the different processes determined by thermogravimetric analysis; also by ICP-AES analysis, it was shown that the inorganic material was eliminated efficiently with the acid treatments used in this study.     

Simple One-Pot Synthesis of New Derivatives of the Macrocyclic Aminal 1,3,7,9,13,15,19,21-Octaazapentacyclo-[19.3.1.13,7.19,13.115,19]octacosane (OAPO)

A series of 2,2′-(dihydropyrimidine-1,3(2H,4H)-diyldimethanediyl)bis(substituted-phenols) was synthesized using a Mannich-type reaction between the macrocyclic aminal 1,3,7,9,13,15,19,21-octaazapentacyclo[19.3.1.1^3,7.1^9,13.1^15,19]octacosane (OAPO) (1) and substituted phenols in basic media. These previously unreported compounds were separated from the reaction mixture by column chromatography in highly pure form with 25–75% yields. The most stable conformer was predicted using AM1-type semiempirical quantum chemical calculations.