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Six copper(ii) complexes of trans-1,2,3-propenetricarboxylic acid (H(3)L) with novel ladder, bi-rack, rack-ladder-rack and layer structures were obtained by the combination of the diverse coordination symmetries and the Jahn-Teller effect of the Cu(2+) ion and the T-shaped coordination mode of the L(3-) or HL(2-) ligand together with the introduction of an inert directing ligand. Solid-state photoluminescent analyses of the present compounds show that they display blue emissions.

On the basis that pinacidil can produce an "all or none" repolarization in right ventricular wall of canine, to observe the effects of quinidine on the marked transmural dispersion of repolarization. Recent studies have shown that ventricular myocardium is composed of at least 3 electrophysiological distinct cell types: epicardial, endocardial, and midcardial cells. Differences in the response of the 3 cell types to pharmacologic agents and/or pathophysiological states often result in amplification of intrinsic electrical heterogeneities, thus providing a substrate as well as a trigger for the development of arrhythmias. The study was designed to observe the right ventricular transmural heterogeneity in vitro canine heart tissue preparation level.The strips were isolated from the anterior wall of the right ventricular of canine. The preparations perfused with oxygenated (95%O(2)/5%CO(2)) Tyrode's solution. The tissues were stimulated at basic cycle lengths of 1000 ms. Standard microelectrode techniques were used. Transmembrane action potentials were recorded from epicardial, midcardial and endocardial cells respectively from right ventricular free wall of canine on different conditions [perusing with Tyrode's solution (Control), pinacidil (2.5 micromol/L), and quinidine (5 micromol/L) in turn].Compared with that of endocardial cells, the action potentials of canine ventricular epicardial and midcardial cells had more obvious spike and dome morphology. Pinacidil (2.5 micromol/L) caused a loss of the dome of transmembrane action potentials and a marked abbreviation of the action potential duration (APD) in right ventricular epicardial and midcardial cells, especially in epicardial cells, but not in endocardial cells (n = 10). With pinacidil (2.5 micromol/L), in epicardial cells, phase 2 amplitude of action potentials decreased from (117.7 +/- 9.3) mV to (71.3 +/- 6.4) mV (P0.01), and 90% of the APD(90) decreased from (198.2 +/- 20.8) ms to (103.9 +/- 13.5) ms (P0.01). The transmural dispersion of action potential duration increased from (48.5 +/- 9.2) ms to (128.7 +/- 13.5) ms (P0.01). Quinidine (5 micromol/L) effectively prolonged the APD abbreviated by pinacidil, restored or partly restored the dome of transmembrane action potentials of epicardial and midcardial cells but not of endocardial cells (n = 10). In epicardial cells phase 2 amplitude increased from (71.3 +/- 6.4) mV to (106.6 +/- 7.7) mV (P0.01), and 90% of the APD(90) increased from (103.9 +/- 13.5) ms to (185.9 +/- 15.7) ms (P0.01). The transmural dispersion of action potential duration significantly decreased from (128.7 +/- 13.5) ms to (54.3 +/- 10.8) ms (P0.01). Quinidine reduced pinacidil-induced transmural dispersion of phase 2 amplitude and the APD in right ventricular wall of canine.By restoring the dome and the APD of the epicardial and midcardial cells action potentials, quinidine (5 micromol/L) could reduce the marked transmural dispersion of repolarization caused by pinacidil.

Five zinc complexes of T-shaped trans-1,2,3-propenetricarboxylic acid (H(3)L) with 1-D ribbon-like chain, 2-D rhombus-grid-like and herringbone-like layers, and non-interpenetrating 3-D open framework have been obtained based on different building blocks. X-ray single crystal analyses show that the T-shaped information of H(3)L was nicely expressed in the construction of herringbone-like or ladder-like structure. All compounds were found to display blue fluorescent emissions.

A new series of novel isostructural metal chalcogenides, K(2)CuIn(3)Se(6) (1), K(2)CuGa(3)Se(6) (2), and K(2)AgIn(3)Se(6) (3), were obtained by a reactive flux technique and structurally characterized. Compounds 1, 2, and 3 crystallize in the space group C2/c of the monoclinic system with eight formula units in a cell: a = 11.445(2) A, b = 11.495(2) A, c = 21.263(4) A, beta = 97.68(3) degrees, V = 2772(1) A(3), R1/wR2 = 0.0676/0.1652 for 1; a = 11.031(2) A, b = 11.050(4) A, c = 20.808(7) A, beta = 97.71(2) degrees, V = 2513(1) A(3), R1/wR2 = 0.0301/0.0511 for 2; and a = 11.633(1) A, b = 11.587(1) A, c = 21.355(1) A, beta = 98.010(8) degrees, V = 2850.4(4) A(3), R1/wR2 = 0.0471/0.0732 for 3. These isostructural compounds are characterized by a chain-sublayer-chain slab structure. The sublayer, composed of alternative corner-sharing mixed-metal tetrahedra, is sandwiched by parallel corner-sharing tetrahedral chains. Optical absorption spectra of compounds 1, 2, and 3 reveal the presence of a sharp optical gap of 1.68, 1.72, and 1.64 eV, respectively, suggesting that these materials are semiconductors and suitable for efficient absorption of solar radiation in solar cell applications. IR spectra show no obvious absorption in the range 800-4000 cm(-)(1).

[1] We measured the long-lived cosmogenic radionuclides 10Be, 26Al, and 36Cl in 47 H chondrite falls: 13 “Cluster 1” members, 9 “Cluster 5” members, and 25 random falls. From the date and time of fall, Clusters 1 and 5 were previously identified as possible coorbital meteoroid streams with distinctive thermal histories being confirmed by contents of volatile trace elements. Here, we use model data, including a three-radionuclide plot (10Bebulk/26Albulk versus 36Clmetal/26Albulk) and the multivariate statistical techniques of logistic regression and linear discriminant analysis to compare radionuclide levels and their utility to differentiate specific suites from other H chondrites. From our radionuclide results and from noble gas data from other workers, we identified 35 falls with simple irradiation histories and cosmic ray exposure ages >4 Ma. Eight others exhibit evidence for shorter (≤4 Ma) exposure, three of which had complex exposure histories (two having been reported by others previously); three others may have had such a history. In any event, the small proportion of H chondrite falls with complex exposure histories supports recent suggestions that they are not commonly encountered, as earlier workers suggested. Although cosmogenic radionuclides do not differentiate between Cluster 1 and a random set of H chondrites, H chondrites that lost 3He from solar heating are distinguishable from those with normal 3He levels.

A direct white-light metal-organic framework (MOF), [AgL](n) x nH(2)O (1, L = 4-cyanobenzoate), obtained by the reaction of deprotonated 4-cyanobenzoic acid and AgNO(3) in water, was found to exhibit tunable yellow-to-white photoluminescence by variation of excitation light. Interestingly, the close pure white emission of 1 has CIE-1931 chromaticity coordinates of (0.33, 0.34) when excited by 349-nm UV light, which is compatible to the light output of the deep UV LED.

In the title compound, [Fe(C7H3NO5)Cl(H2O)2]·C12H24O6·2H2O or [Fe(HChel)Cl(H2O)2].(18-crown-6)·2H2O, where H3Chel is 4-hydroxy­pyridine-2,6-dicarboxylic (chelidamic) acid, the FeIII atom exhibits a distorted octa­hedral geometry coordinated by two O atoms and one N atom from the tridentate chelidamate ligand, one Cl atom and two water mol­ecules. O—H⋯O hydrogen bonds from the coordinated water mol­ecules to the O atoms of the crown ether form one-dimensional hydrogen-bonded chains with alternating [Fe(HChel)Cl(H2O)2] and 18-crown-6 units. The solvent water mol­ecules lie between these chains, accepting O—H⋯O hydrogen bonds from the hydroxyl groups of the chelidamate ligands, and forming O—H⋯O hydrogen bonds with the noncoordinated O atoms of the carboxyl­ate groups.

The title Schiff base compound, C18H22N4, is derived from the condensation reaction of hydrazine and 4-(dimethyl­amino)benzaldehyde. There is a crystallographic centre of symmetry at the mid-point of the N—N bond.

A novel inorganic–organic hybrid [Cu(2,2′-bipy)2I]2n(PbI3)2n·nDMF·nH2O (1), which exhibits diplex single-crystal-to-single-crystal transformation, can transform to a guest molecule released compound [Cu(2,2′-bipy)2I]n(PbI3)n (1a) by thermal induction, or to both a guest molecule released and ligand exchanged compound [Cu(2,2′-bipy)3]n(Pb2I6)n (1b) by solvent induction.

A series of one-dimensional (1-D) N-succinopyridine-based complexes: [Cu(L−)(H2O)2]Cl·2H2O (1), [Pr(L−)(H2O)4]Cl2 (2), [Ln(L−)(H2O)5]Cl2·3H2O (Ln = Eu (3), Gd (4)), and [Er(L−)(H2O)4]Cl2·H2O (5) (HL = N-succinopyridine (−OOC–CH(N+C5H5)–CH2–COOH)) have been prepared and characterized by single-crystal X-ray diffraction. The frameworks of complexes 1, 2 and 5 constructed from dinuclear metal building blocks exhibit 1-D double-strand loop-like chains; these chains are further connected to each other by hydrogen bonds forming a 3-D supramolecular architecture. Whereas complexes 3 and 4 feature hydrogen bonding 2-D supramolecular networks assembled from 1-D chains that are constructed from mononuclear metal building blocks. The effects of different metal ions, steric hindrance and coordination diversities of HL on the polymeric architectures have been discussed. In addition, thermogravimetric and magnetic properties of these complexes were also investigated in this paper.

A Pd/α-Al2O3 nanocatalyst with ultra-low Pd loading exhibits high activity and stability for CO oxidative coupling to dimethyl oxalate, which was prepared by a Cu(2+)-assisted in situ reduction method at room temperature. The small size and high dispersion of Pd nanoparticles facilitated by Cu(2+) ions are responsible for the excellent catalytic activity.

We investigate the impact of different derivatives of 1,4-diazabicyclo[2.2.2]octane on the crystal structures of iodoplumbates by systematically increasing the size of the same organic amine, and present two new 1-D iodoplumbates. Optical studies reveal the semiconductor characteristics of all as-synthesized iodoplumbate hybrids.

The reaction of FeCl3, NaSCN and Gd(NO3)3·6H2O in 1:10 DMF/H2O led to the formation of the title compound, [Fe(NCS)3(C4H7N)3], in which the six-coordinated Fe atom is in an octahedral fac environment.

Two fluorescent cadmium complexes, [HL][CdCl2(H2O)2] (1) and [HL][CdBr2(H2O)2] (2) (HL = N-succinopyridine), have been prepared and characterized by single-crystal X-ray diffraction. Complex 1 contains a unique μ2-Cl bridged neutral 2D inorganic layer, which is further connected to isolated HL molecules by hydrogen bonds forming a hamburger-like OIO 2D supramolecular architecture. Complex 2 features a 3D supramolecular network assembly from 1D inorganic chains and discrete organic molecules through hydrogen bonds. Thermogravimetric, luminescent properties and theoretical calculations of 1 and 2 are also discussed. Moreover, UV-to-Vis tunable emissions for N-succinopyridine and 1 as well as blue-to-green tunable emission for 2 are observed.

A novel inorganic–organic hybrid (H2DAB)(Pb2I6)·2H2O, is employed as a new nitrite detection reagent with extremely high sensitivity and selectivity, in which the organic component features dual functions that afford a self-supplied acidic environment and act as a reagent for spectrophotometrically detecting nitrite anions. This new nitrite detection reagent effectively simplifies the test procedure and can be used to qualitatively distinguish nitrites with the naked eye in rural and remote areas.

The stabilization of the (SnS4)4− anion in the coordination of [Mn(phen)]2+ complexes brings about a novel compound {[Mn(phen)]2(SnS4)}n·nH2O (1), in which an unprecedented link mode of the (SnS4)4− anion is observed. Theoretical calculations indicate that TM complexes with big π-conjugated ligands, such as [Mn(phen)]2+, can serve as an excellent electron reservoir to stabilize the (SnS4)4− anion in 1, despite its strong condensation tendency. Magnetic measurements show the presence of strong antiferromagnetic interactions between the Mn2+ ions in 1.

Electron transport variations in individual ZnS nanowires synthesized through a chemical vapor deposition process were in situ studied in transmission electron microscope under convergent electron-beam irradiation (EBI). It was found that the transport can dramatically be enhanced using proper irradiation conditions. The conductivity mechanism was revealed based on a detailed study of microstructure and composition evolutions under irradiation. EBI-induced Zn-rich domains’ appearance and related O doping were mainly responsible for the conductivity improvements. First-principles theoretical calculations additionally indicated that the generation of midbands within a ZnS band gap might also contribute to the improved conductivity.

Nanoelectrodes are fabricated from individual carbon nanotubes (CNTs) connected to tungsten probes or carbon fibers. The whole electrode was covered by an insulating HfO(2) layer except for a section of conducting CNT at the apex. The fabrication process includes mounting individual CNTs to the conductive support through nanomanipulation, coating the whole probe by a dielectric layer using atomic layer deposition and removing the dielectric layer at the apex through a nanomanipulation process. Differential pulse voltammetry and cyclic voltammetry measurements show the CNT nanoelectrode has similar electrochemical behavior to the widely used carbon fiber probe, but has a much smaller active electrode area and can provide much higher spatial resolution and signal-to-noise ratio.

Using cyanide anions and sulfur simple substance as precursors of thiocyanate groups, three desired luminescent halogeno-thiocyano-d10 metal complexes, namely, [Me4N][Cu(SCN)Br] (1) with a 1-D to 2-D architecture constructed through C–H⋯Br hydrogen bonds, [Me4N][Cu(SCN)I] (2) with a 1-D to 3-D framework constructed through C–H⋯I hydrogen bonds, and [Me4N][Ag2(SCN)2Cl] (3) with a special 3-D nanoporous structure constructed by µ-chloride atoms connecting the 2-D neutral ∞2[Ag2(SCN)2] layers, have been solvothermally synthesized and all exhibit efficient luminescence. The luminescent behavior of the three complexes was illustrated through the density functional theory.

NSF of China [20701037, 20801026]; NSF for Distinguished Young Scientist of China [20425104]; 973 program [2009CB939801]; Key Project from the CAS [KJCX2.YW.M10]; NSF of Fujian Province [2008I0026]

A ferroelectric inorganic–organic hybrid based on in situ substituted stilbazolium cation (TAMS2+ = trimethylamino-N-methyl stilbazolium) has been obtained. Single-crystal X-ray structure analysis demonstrates that the NLO-phore organic component of the complex is embedded into the inorganic polymeric [Bi2Cl8]2− framework and shows a polar arrangement with the cooperation of the nonsymmetric inorganic component. The measurement of ferroelectric and nonlinear optical properties show typical ferroelectricity and second harmonic generation (SHG) responses as well as a significant improvement of the laser damage threshold and thermal stability of relative organic material.

The title compound, {[Mn-3( C6H3O6)center dot 0.2(H2O)(6)]center dot 0.2H(2)O}(n), contains a three- dimensional open framework formed by each organic ligand mu(3)-bridging three six-coordinated Mn-II atoms (one of which resides on a twofold crystallographic axis). Uncoordinated water molecules are located in the channels of the framework along the c-axis direction. The primary O-H center dot center dot center dot O intermolecular interactions have O center dot center dot center dot O distances ranging from 2.680 (4) to 3.020 ( 13) angstrom and O-H center dot center dot center dot O angles ranging from 125 (4) to 179 (4)

A new mixed-framework mercury selenide diselenite, (Hg(3)Se(2))(Se(2)O(5)) (1), has been prepared by a solid-state reaction and structurally characterized by single-crystal X-ray diffraction analysis. The crystal structure of 1 consists of parallel stair-like cationic (Hg(3)Se(2))(2+) chains, which are bridged by (Se(2)O(5))(2-) anionic groups to form a novel 2-D layered mixed-framework. The optical properties were investigated in terms of the diffuse reflectance and microscopic infrared spectra. The electronic band structure along with density of states (DOS) calculated by the DFT method indicates that compound 1 is a semiconductor, and that the optical absorption of 1 is mainly ascribed to the charge transitions from the O-2p and Se(-II)-4p states to the Se(IV)-4p and Hg-6s states.

Electron field emission measurements on individual carbon nanotubes (CNTs) were performed inside a transmission electron microscope. Controlled removal of carbon atoms at the tip of the CNT was realized and various tip structures were fabricated. In particular, a capped CNT was opened and an opened CNT was converted into a capped CNT, and corresponding field emission characteristics were measured. Our results show that the electron field emission properties of CNTs are highly sensitive to the emission tip structures. The ability to modify the tip structure thus provides a way to control the field emission property of the CNT and vice versa.

Four new tris(ethylenediamine)-chelated metal complexes [Zn(en)3]I2·0.5en (1), [Cd(en)3]Cl2·H2O (2), [Cd(en)3]Br2 (3), and [Hg(en)3]Cl2 (4) have been synthesized by solvothermal reactions. The complexes contain discrete [M(en)3]2+ (M = Zn, Cd, Hg) cations and halide anions. The Zn2+ and Cd2+ ions are six-coordinated by three ethylenediamine molecules to form octahedra, while the Hg2+ ion has a trigonal prism coordination geometry. These complexes all display fluorescent properties in the blue range, which are attributed to a ligand-to-metal charge-transfer mechanism according to molecular orbital calculations. The solid-state diffuse reflectance spectra show that 1–4 are wide band-gap semiconductors. IR and thermogravimetric analyses for 1–4 are also presented in this paper.

Environmental Context.The first Solar System material condensed 4.567 billion years ago, rapidly forming planetesimals—solid bodies that might combine to form planets (accretion) or survive as asteroidal meteorites. Earth’s main accretion ended within the next 30 million years, but subsequent high temperatures essentially erased evidence of this history. However, heating in these early episodes produced effects uniquely recorded by 14 volatile trace elements. The volatile element composition of chondritic meteorites, whose parent material formed closest to Earth, may thus provide important information about early planetesimal evolution. Abstract.We report data for 14 trace and ultratrace elements—Au, Co, Sb, Ga, Rb, Ag, Cs, Te, Zn, Cd, Bi, Tl, In (ordered by increasing putative nebular volatility)—in 13 enstatite (E) chondrites recovered from Antarctica and two E inclusions in the Kaidun polymict breccia that fell in 1980. These data, determined by radiochemical neutron activation analysis (RNAA), essentially double the amount of information known for E chondrites, whose parent materials formed closest to the Sun in the chondrite-forming nebular region. We discuss here the data for all 29 samples studied. The meteoritic suite studied here includes both representatives of previously rare types—like high-iron EH3 and EH5 individuals—but also unique individuals and previously unknown low-iron, EL3, chondrites. Prior hypothetical assertions by others are corrected by the new data. Volatile element contents of EL3 and EH3 chondrites are variable, but comparable, like those of type 3 ordinary chondrites (i.e. H3, L3, and LL3). Volatile element contents of EH4 chondrites are at least as high as those of the E3 types, in contrast to the lower contents of H4, L4, and LL4 types. Compositionally, E3,4 chondrites reflect only nebular condensation and/or accretion processes. Volatiles in E5 and E6 chondrites—whether of EH, EL or unique ones—are depleted relative to cosmic (i.e. CI1) or E3,4 chondrite abundances. The evidence indicates that E5,6 chondrites compositionally reflect vaporization and loss of volatiles during open-system, thermal metamorphism of their parent(s); this may have been the terrestrial environment during Earth’s formation from early planetesimals. Compositional differences between Antarctic E5,6 chondrites and contemporary falls probably do not reflect weathering during the long residence of these chondrites in Antarctica. They might reflect differences in the starting compositions and/or metamorphic conditions in the parent(s).

Five zinc complexes of T-shaped trans-1,2,3-propenetricarboxylic acid (H(3)L) with 1-D ribbon-like chain, 2-D rhombus-grid-like and herringbone-like layers, and non-interpenetrating 3-D open framework have been obtained based on different building blocks. X-ray single crystal analyses show that the T-shaped information of H(3)L was nicely expressed in the construction of herringbone-like or ladder-like structure. All compounds were found to display blue fluorescent emissions.