Thermoelectrical Investigation of Rare Earth Sulfide Materials

Results? are presented on synthesis?? and crystal growth of? Gd2S3-Dy2S3 solid solution sulfides and study of their thermoelectric properties in the range of temperatures 80-400 K. Gd0.2Dy0.8S1.48 composition has the best values of thermoelectric efficiency 0.39 x 10-3/K at 400 K.

HELIX SENSE-SELECTIVE COPOLYMERIZATION OF TRIPHENYLMETHYL METHACRYLATE WITH CHIRAL ANIONIC INITIATORS

Optically active copolymers of pairs of three monomers, triphenyl (methyl methacrylate)and one or two pyridyl substituted methyl methacrylate homologues, were obtained by helix-sense-selective copolymerization using complexes of organolithium with chiral ligand as anionicinitiators in toluene at low temperature. The copolymers obtained with (-)-sparteine (Sp) and(S,S)-(+)-and (R, R)-(-)-2, 3-dimethoxy-1, 4-bis (dimethylamino) butanes((+)-and (-)-DDB) complexes of organolithium showed low optical activity, but PMP complex with N, N-diphenylethyleneamine monolithium amide (PMP-DPEDA-Li) was effective in synthesizingcopolymers of high optical rotation ([α]_D^(25) about+320～1370°)which were comparable to thoseof relative homopolymers with one-handed helical structure.

Extracellular ATP mediates H_2S-regulated stomatal movements and guard cell K^+ current in a H_2O_2-dependent manner in Arabidopsis

Hydrogen sulfide （H2S） is a newly discovered gaseous signaling molecule and involved in ethylene and ABA-induced stomatal closure. As an important factor, extracellular ATP （eATP） was believed to participate in regulation of stomatal closing. However, the mechanism by which eATP mediates HES-regulated stomatal closure remains unclear. Here, we employed Arabidopsis wild-type and mutant lines of ATP-binding cassette transporters （Atmrp4, Atmrp5 and their double mutant Atmrp4/5） to study the function of eATP in H_2S-regulated stomatal movement. Our results indicated that H_2S affected stomatal closing through stimulating guard cell outward K^＋ current. Moreover, we found that HES induced eATP generation by regulating the activity of an ABC transporter. The inhibitor of ABC transporters, glibenclamide （Gli）, could impair H_2S-regulated stomatal closure and reduce H_2S-dependent eATP accumulation in Atmrp4 and Atmrp5 mutants. In addition, the promotion effect of H_2S on outward K^＋ currents was diminished in Atmrp4/5 double mutant. Our data suggested that hydrogen peroxide （H_2O_2） is required for H_2S-induced stomatal closure, and the production of H_2O_2 is regulated by eATP via NADPH oxidase. Based on this work, we conclude that H_2S-induced stomatal closure requires ABC transporter-dependent eATP pro- duction and subsequent NADPH oxidase-dependent H_2O_2 accumulation.

Cucurbit[6]uril-based supramolecular frameworks assembled via the outer surface interaction of cucurbit[n]urils

Curcurbit[n]uril(Q[n])-based supramolecular frameworks(QSFs) constructed from the outer surface interaction of Q[n]s(OSIQ) have the characteristic of simplicity,diversity and modulability.Their simplicity is reflected in their simple composition and preparation methods used for QSFs.The diversity of supramolecular organic frameworks(SOFs) is reflected in the synthesis methods and structural characteristics of the as-obtained QSFs,as well as the variety of structural directing agents and basic building blocks used to prepare QSFs.The modulability is reflected by the controllable channel size in the QSFs,which can be adjusted using different sizes of Q[n]s.In this work,the first re ported cucurbituril Q[6]was selected as the basic building block and three Q[6]-based su p ramolecular frameworks were obtained from aqueous HCl solutions in the presence of [CdCl_(4)]^(2-)respectively.The OSIQs are the main driving forces for the formation of these frameworks.This study shows the diversity of the QSFs.