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Abstract: Four supramolecular complexes [MnL1(H2O)2] (1), {[CoL2(OAc)(H2O)]2Co}·5CH3CH2OH (2), {[NiL3(OAc)(CH3OH)]2Ni}·2CH3COCH3·2CH3OH (3) and {[ZnL2(OAc)]2Zn}·CHCl3 (4), have been synthesized and characterized by elemental analyses, IR, UV–Vis spectra and X-ray diffraction techniques. All the complexes have the trinuclear configuration except for MnII complex being mononuclear configuration. Every trinuclear complex contains two acetate ions coordinate to the three metal ions via a familiar M–O–C–O–M (M=Co, Ni, Zn) coordinated mode. Although complexes 1 and 3 display 1D supramolecular chains, the different coordination environments (mononuclear in 1, trinuclear in 3) provoke divergence in the structures and aggregations of the chain subunits. Complex 2 forms a 3D hydrogen-bonding supramolecular networks possessing a channel composing of six O–H···O hydrogen bonds, while complex 4 exhibits a 2D hydrogen-bonding supramolecular networks with the formation of “grottos” occupied by chloroform molecules through intermolecular hydrogen-bond interactions. The spectral properties of the title complexes have been further discussed in detail. [Copyright &y& Elsevier]

Objectives Toxicity caused by pharmacological and chemical substances, including carbon tetrachloride (CCl4), is a major pathological factor for liver injury. Therefore, strategies to prevent toxicity are needed for maintaining a healthy liver. This study was designed to determine whether recombinant bovine pancreatic trypsin inhibitor (rBPTI), a non-specific serine protease inhibitor, prevents CCl4-induced liver injury in mice. Methods Mice were treated with CCl4 in the presence or absence of co-treatment with rBPTI. Liver sections were prepared for histopathological assessment. Liver function was evaluated by detecting serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and liver index. Liver oxidative stress and inflammation were examined by detecting the liver malondialdehyde level and glutathione and superoxide dismutase activity, and serum tumour necrosis factor-α level, respectively. Key findings CCl4 induced hepatocyte necrosis, inflammatory cell infiltration and fatty degeneration, which were ameliorated by co-treatment with rBPTI in a concentration-dependent manner. Furthermore, rBPTI prevented CCl4-induced disruption of liver function. Importantly, rBPTI reduced CCl4-induced liver oxidative stress response and pro-inflammatory cytokine production. Conclusions These results indicated that rBPTI exerted a protective effect on CCl4-induced liver injury in mice. Thus, rBPTI may have potential application for prevention of liver injury induced by metabolism of drugs and toxic substances. [ABSTRACT FROM AUTHOR]

Abstract: Exposure to ultraviolet B (UVB) irradiation (290–320nm wavelength) from sunlight induces a variety of medical problems, including sunburn, immunosuppression and skin cancers. However, the molecular mechanisms related to UVB-induced cell damage and/or mutagenic effects have not been fully defined. Here, we demonstrate that one of the catalytic subunits of the IκB kinase complex (IKK), IKKα, plays a critical role in mediation of the UVB-induced G0/G1 cell cycle arrest response by suppressing Cyclin D1 expression. Notably, IKKa-dependent Cyclin D1 regulation is unrelated to IKKβ/NF-κB activity. We further show that IKKα-dependent downregulation of Cyclin D1 expression in the UVB response results from the reduction of ERK1/2-dependent Cyclin D1 transcription coupled with an increase of p38 kinase-dependent Cyclin D1 proteolysis. Thus, our results have identified the novel role of IKKα in regulating cell cycle progression during the cellular UVB response. Targeting IKKα might be promising for the prevention of UVB-induced cell damage and tumorigenic effects. [Copyright &y& Elsevier]

The structures and electronic properties of a number of real and hypothetical ABX2 compounds sharing (or evolving from) a single P4/mmm structural type are examined. These include the known CaCuO2 and SrFeO2 phases. A number of variations of Ihis P4/mmm ABX2 framework, some obvious, some exotic, all with a chemical motivation, were investigated: A = alkali metal, alkaline earth metal or La, B = Ti, Fe, Cu, or Pt, and X = C, O, S, C2, H2, or F. Careful attention was given to the d-orbital splitting patterns and magnetic states (ferromagnetic or antiferromagnetic) of these compounds, as well as their stability gauged by phonon dispersions and energetics. The most interesting as yet unmade compounds that emerged were (a) a carbide SrFe(C2)2, containing C2 units with a C-C distance 011.267 Å, (b) an AeTiO2 series, with Ti-Ti bonding, part σ, part π, luned by the Ae2+ cation size, and (c) NaPtF2, for which a second structure was found, containing a hexagonal layering of (PIF2) molecules. [ABSTRACT FROM AUTHOR]

Abstract: Effect of dissolved oxygen (DO) concentration on simultaneous removal of carbon and nitrogen by a membrane aeration/filtration combined bioreactor (CMBR) was investigated through experimental test, which used synthetic municipal wastewater. The results showed that the CMBR achieved a good simultaneous removal of carbon and nitrogen when DO concentration was around 0.5mg/L. Under this condition, the COD, ammonia and TN removal efficiency could reach to 94.5%, 96.0% and 78.4%, respectively. When the DO concentration decreased to 0.1mg/L, the limitation of oxygen led to the hampering of nitrification and low removal efficiency of ammonia and TN which were just 69.3% and 65.7%, respectively. When DO was set to around 2.0mg/L or 4.0mg/L, the COD and ammonia removal rate could be as high as 96%, but the TN removal efficiency was dropped to 50.4% and 26.4%, respectively. All of the above results suggested that controlling DO around 0.5mg/L in CMBR was good for the removal of COD, ammonia and TN simultaneously. [Copyright &y& Elsevier]

Abstract: Two solvent-induced trinuclear nickel(II) clusters, [{NiL(CH3OH)}2(OAc)2Ni]·2CH3OH (I) and [{NiL(C2H5OH)}2(OAc)2Ni]·2C2H5OH (II), have been synthesized by the reaction of a new Salen-type bisoxime chelating ligand of 5,5′-di(N,N′-diethylamino)-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol (H2L) with nickel(II) acetate tetrahydrate in different solvents. Clusters I and II were characterized by elemental analyses, IR spectra, UV–vis absorption spectra, TG–DTA and X-ray diffraction methods. In clusters I (or II), there are two ligand moieties (which provide N2O2 donors), two acetate ions, two coordinated methanol (or ethanol) molecules and two crystallizing methanol (or ethanol) molecules, which result in the formation of three slightly distorted octahedral geometries around Ni(II) ions. Interestingly, nickel(II) ions in the structures of clusters I and II are all six-coordinated geometry, but clusters I and II are grown up in different solvent. Right because of this, solvent effect cause to their different crystal structures. [Copyright &y& Elsevier]

Abstract: Four new solvent-induced Cu(II) complexes with the chemical formulae [{Cu(HL)(CH3OH)}2Cu]·CH3OH (1), [{(Cu(HL))2(CH3CH2OH)2}Cu] (2), [{CuL(H2O)}2Cu2]·2CH3CH2CH2OH (3) and [{(Cu(HL))2(CH3CH2CH2CH2OH)2}Cu] (4), where H4L=6,6′-dihydroxy-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol, have been synthesized and characterized by elemental analyses, 1H NMR, FT-IR, UV–Vis spectra, TG-DTA, molar conductances and X-ray crystallography. Complexes 1, 2 and 4 have an elongated square-pyramidal geometry with an unusually long bond from the penta-coordinated Cu(II) centres to the oxygen atoms of the apically coordinated solvent (methanol, ethanol or n-butanol) molecules for the terminal Cu(II) ions, and a square planar geometry distorted tetrahedrally for the central Cu(II) ion. In complex 3, the terminal Cu(II) ions have trigonal bipyramidal coordination geometries constituted by equatorial O2N donor sites, with one oxygen atom from one of the coordinated water molecules and one nitrogen atom from a completely deprotonated L4− ligand unit in the axial positions, and the central Cu(II) ions are in slightly tetrahedrally distorted square planar geometries constituted by four phenoxo oxygen donors from two completely deprotonated L4− ligand units, and these form a tetrametal Cu–O–Cu–O–Cu–O–Cu–O eight-membered ring. These four complexes exhibit strong hydrogen bonding interactions in the solid state. Moreover, co-crystallizing n-propanol molecules link two other adjacent complex molecules into a self-assembled infinite 2D supramolecular structure via the intermolecular hydrogen bonds in complex 3. [Copyright &y& Elsevier]

Abstract: Zirconia precursor nanowires were synthesized via the solvothermal reaction of zirconium tetra-n-propoxide Zr(OPr n )4 with ethylene glycol and 1-butyl-3-methyl imidazolium tetrafluoroborate ionic liquid at 160 °C. The as-synthesized nanowires were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), thermogravimetric and differential scanning calorimetric (TG-DSC) analysis, and infrared spectroscopy (IR), etc. The length of the as-synthesized nanowires reaches ∼20 μm, and the width ∼50 nm, giving an aspect ratio of a few hundreds. Upon calcination at elevated temperatures, the zirconia precursor nanowires transform from relative dense structure into highly porous ZrO2 nanowires consisting of interconnected nanocrystallites; in addition the length of the nanowires is greatly reduced. Cyclic voltammetry measurement shows that the modification of the graphite electrode with the ZrO2 nanowires greatly enhances sensitivity of the detection of vanadium, suggesting that ZrO2 nanowires may find important applications in vanadium(V) determination using electroanalytical methods with chemically modified electrode technique. [Copyright &y& Elsevier]

Abstract: Defects induced by KrF-excimer laser irradiation in the soda-lime silicate glass were studied by means of optical spectrophotometric and electron spin resonance measurements. Three induced absorption bands at peak position of 610, 420, and 275nm were determined in the glass after the UV-laser radiation, with the assistance of Gaussian resolution method. The defects of nonbridging oxygen hole centers attributed to two absorption peaks at 610 and 420nm, and the trapped electrons correlated to the absorption at 275nm. The induced absorption bands increased when laser irradiation time or energy density increased. [Copyright &y& Elsevier]

Abstract: Rosette-like ammonium flurorzirconate (NH4Zr2F9) aggregates have been synthesized via a novel reaction route by using zirconium oxychloride, urea, 1-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) and hydrochloric acid in ethanol solution. The as-synthesized NH4Zr2F9 can be changed from rosette-like aggregates to hexagonal plates by varying synthesis conditions. Upon calcination at high temperature NH4Zr2F9 transforms from relative dense structure into highly porous ZrO2 with similar morphology consisting of interconnected nanocrystallites. [Copyright &y& Elsevier]

Abstract: Two Salen-type ligands (H2L1, 4,4′-dichloro-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol and H2L2, 4,4′-dinitro-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol) and their corresponding complexes ({[CoL1(MeOH)]2(OAc)2Co}·2MeOH and [CuL2]2) have been synthesized and characterized by element analyses, 1H NMR, FT-IR and UV–Vis spectra, TG-DTA and single crystal X-ray crystallography. Crystallographic data suggests the octahedral geometry for Co(II) complex and square-pyramidal geometry for Cu(II) complex. Furthermore, the fluorescence behavior of Cu(II) complex in DMSO is discussed. [Copyright &y& Elsevier]

We present a theoretical study of the electronic structures of Au2PbP2, Au2TIP2, and Au2HgP2. Structurally, these compounds contain a framework of condensed Au2P6 and Au4P6 rings forming parallel channels, which are filled by lead, thallium, or mercury atoms. Given the linear coordination of the Au atoms and the existence of zigzag -[P-P-P]- singly-bonded chains in them, these materials present us with a rare instance of approximately linear, one-dimensional, and zerovalent element (Pb, Tl, or Hg) chains with a variable electron count. The Pb-Pb, Tl-Tl, and Hg-Hg element lines in these structures have somewhat longer bond lengths than their respective single bond lengths or their separations in (calculated) isolated chains. Yet, the zerovalent element interactions are prominent and are responsible for the metallicity of some of these materials. In the calculations, both Au2PbP2 and Au2TIP2 emerge as metallic, whereas Au2HgP2 is a semiconductor. The isolated element chains do not undergo a pairing (Peierls) distortion nor do the chains in the three-dimensional ternaries. The small barrier for mobility of the Pb, Tl, and Hg atoms along the chain axis may explain the large thermal parameters observed in the crystal structures along the chain axis (and the need to use fractional occupations of several positions along the chain). These ternaries may show one-dimensional liquidlike behavior under some conditions. [ABSTRACT FROM AUTHOR]

Abstract: Three new supramolecular complexes, [Cu(L1)H2O] n (1), [Zn(L2)(H2O)2] n (2), and [Cd(L2)(H2O)2] n (3), have been synthesized and characterized by FT-IR spectra, fluorescence spectra, and thermal analyses. And the structures of complexes 1–3 have been elucidated by X-ray analyses. Complex 1 is square pyramidal geometry with an unusually long bond (2.262Å) from penta-coodinated CuII center to the oxygen atom of the apical coordinated water molecule. Molecules are linked by hydrogen bonding between the coordinated water and the phenolic oxygen atoms of adjacent molecules, thus formed a self-assembling continual zigzag chain supramolecular structure. The crystal structure of complex 2 (or 3) has indicated that the complex consists of one ZnII (or CdII) atom, one L2− unit and two coordinated water molecules, the coordination number of the ZnII (or CdII) atom is six, and formed an infinite metal–water chain supramolecular structure by intermolecular hydrogen bonds and π–π stacking of neighboring benzene rings. Meanwhile, the thermal and photophysical properties of the resulted complexes have also been discussed. [Copyright &y& Elsevier]

Abstract: A tri-nuclear cobalt(II) cluster, [(CoL)2(OAc)2Co]·2C2H5OH, has been synthesized by the reaction of cobalt(II) acetate tetrahydrate with a novel Salen-type bisoxime chelating ligand, 3,3′-dimethoxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L), and characterized by elemental analyses, IR spectra, TG-DTA and molar conductances. UV–vis spectroscopic titration in methanol solution clearly indicated the exclusive formation of the 3:2 [Co3L2]2+ cluster. The single-crystal X-ray diffraction determination of the Co(II) cluster shows that there are two acetate ions coordinate to three cobalt(II) ions through Co–O–C–O–Co bridges, and quadruple μ-phenoxo oxygen atoms from two [CoL] chelates also coordinate to cobalt(II) ions. Interestingly, different conformational central ions: five- and six-coordinated geometries were found in the cluster. [Copyright &y& Elsevier]

Abstract: Copper oxalate nanowires were synthesized via the reaction of Cu(CH3COO)2·4H2O and oxalic acid in ethanol solution with the aid of 1-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) ionic liquid under solvothermal conditions at 180°C. The as-synthesized nanowires were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), thermogravimetric analysis and differential scanning calorimetric analysis (TG-DSC). The length of the nanowires reaches ∼10μm, and the width ∼30nm, giving an aspect ratio of a few hundreds. The formation of the nanowires follows a novel mechanism based on the reorganization of a copper oxalate solid phase. The copper oxalate nanowires can further transform from a dense structure (enclosed by a smooth surface) into highly porous CuO nanowires consisting of interconnected nanocrystallites. [Copyright &y& Elsevier]

The band structure of ferroelectrics can be modulated by mechanical stress induced piezoelectric polarization charges, and thus to promote the separation of photo-excited carriers, endowing photo-piezocatalysts with good performance in hydrogen production and pollutants degradation. However, the catalytic performance of these conventional photo-piezocatalysts is restricted since they mainly harvest UV light and generally have limited piezoelectricity. Here, in this study, by using self-propagation high-temperature synthesis process, highly piezoelectric gap-state-engineered nano relaxor ferroelectric at the morphotropic phase boundary, such as (Na 0.5 Bi 0.5)TiO 3 -Ba(Ti 0.5 Ni 0.5)O 3 is synthesized for the first time and shows unprecedently light harvesting from UV to near-infrared (λ < 1300 nm). We demonstrate a significantly enhanced photo-piezocatalytic performance for this photo-piezocatalyst. A high hydrogen production rate of ~ 450 μmol g−1 h−1 is obtained and the decomposition of Rhodamine B dye is nearly completed after 20 min under irradiation and ultrasonic vibration. Moreover, an unprecedently efficient NIR-driven photocatalytic degradation of RhB is also demonstrated by using photo-piezocatalysts. This kind of novel multifunctional nano photo-piezocatalysts opens up new horizons to all-day available photo-piezocatalytic technology for a more efficient use of multisource energies from environment. [Display omitted] • Nano ferroelectrics at MPB can be successfully bandgap-engineered for the first time. • Nano ferroelectrics show excellent solar light absorption from UV to NIR. • Novel ferroelectrics can successfully harvest multisource sustainable energies from light and vibration. • High-performance pollutes degradation and H 2 production are achieved. • NIR-driven photoferrocatalytic degradation of pollutants is demonstrated for the first time. [ABSTRACT FROM AUTHOR]

A templating method for fabricating two-dimensional (2D) arrays of micron-sized gold rings is reported. The microstructures are formed by electroless plating in a through-porous polymer membrane on a silicon substrate obtained from a closed-packed silica colloidal crystal. Our results show that the sizes of gold rings can be altered by varying electroless plating conditions for the porous polystyrene membranes. Moreover, we explain the growth mechanism of gold rings using the classical crystal growth theory that is preferential nucleation at reentrant sites. [ABSTRACT FROM AUTHOR]

Abstract: Hollow ZrO2 microspheres with mesoporous shells have been synthesized by a novel hydrothermal reaction of zirconium oxychloride in the presence of urea, hydrochloric acid, and ethanol. The morphology and shell thickness of the hollow microspheres can be controlled by varying synthesis conditions. After calcination at high temperature, the morphologies of the hollow microspheres are essentially preserved. Pt catalyst supported on the hollow calcined ZrO2 microspheres exhibits more excellent catalytic performance in CO oxidation than those on ZrO2 powders derived from conventional precipitation methods. [Copyright &y& Elsevier]

Abstract: ZnO and Cu2O nanoparticles can be formed through the thermal decomposition of the complex between Zn or Cu with polyamic acid (PAA), accompanying with the formation of polyimide (PI). Transmission electron microscopy (TEM) analysis showed that the formation of ZnO nanoparticles needs a longer curing time than that of Cu2O. Fourier transform infrared spectroscopy (FT-IR) characterization shows that both Zn and Cu will delay the imidization process of PAA. However, the retarding degree of imidization process is higher for Zn than that of Cu. Further investigation showed the structure of Zn–PAA complex is different from that of Cu–PAA, which is the reason for the difference of initial imidization temperature. Thermogravimetric and differential thermal analysis (TG–DTA) characterization agrees well with the results of FT-IR. Also, the thermal decomposition temperature of the polyimide was changed by the involvement of Zn or Cu during curing. [Copyright &y& Elsevier]

Abstract: Two new coordination polymers, [Ag(tza)]∞ (1) (Htza=tetrazole-1-acetic acid) and [Cu(tza)2]∞ (2) have been prepared at room temperature and characterized by X-ray crystallography, IR, UV–vis, fluorescence spectra and magnetism analysis. Compound 1 exhibits extended helical chains through bridging ligand tza. The Ag ctions between the adjacent chains form a 3-D framework featuring the extended tza-connected Ag chains that obviously affect the photoluminescent property. Compound 2 features undulated layered structure with hourglass-shaped [Cu4(tza)4] as subunits with the weak ferromagnetic interactions between Cu(II) ions, which are further stabilized by inter-lamellar Ch name="rad" /> n bonds in the resulting 3-D supramolecular framework. [Copyright &y& Elsevier]

Tri-nuclear cobalt and nickel complexes ([(CoL)2(OAc)2Co] · THF (I) and [(NiL)2(OAc)2(THF)2Ni] · THF (II)) have been synthesized by reaction of a new Salen-type bisoxime chelating ligand of 2,2'-[ethylenedioxybis(nitrilomethylidyne)]dinaphthol(H2L) with cobalt(II) acetate tetrahydrate or nickel(II) acetate tetrahydrate, respectively. Complexes I and II were characterized by elemental analyses, IR, TG-DTA and 1H-NMR etc. The X-ray crystal structures of I and II reveal that two acetate ions coordinate to three cobalt or nickel ions through M-O-C-O-M (M = Co or Ni) bridges and four μ-naphthoxo oxygen atoms from two [ML] units also coordinate to cobalt(II) or nickel(II). Complex I has two distorted square-pyramidal coordination spheres and an octahedral geometry around Co1. In complex II all three nickel ions are six-coordinate. [ABSTRACT FROM AUTHOR]

A lanthanide-transition heterometallic supramolecular complex {Eu(DMF)4(H2O)2Cr(CN)6·H2O}n (1) has been synthesized based on the reaction of K3[Cr(CN)6], N,N-dimethylformamide (DMF) and Eu(NO3)3·6H2O. 1 crystallizes in the monoclinic space group P2(1)/c with a=13.130(6)Å, b=12.923(7)Å, c=19.184(9)Å and Z=4. In 1 each Eu(III) is eight-coordinate with six oxygen atoms from four DMF molecules and two H2O molecules and two nitrogen atoms from two cis-bridging CN ligands to form a distorted dodecahedron. 1 has a three-dimensional network created by the incorporation of coordinative linkage, three inter-molecular and an intrachain hydrogen bond. [ABSTRACT FROM AUTHOR]

Abstract: Tin oxide (SnO2) microspheres with an average 2.5 μm in diameters have been successfully synthesized through a rapid hydrothermal process heating by microwave in the presence of an ionic liquid 1-butyl-3-methyl imidazolium tetrafluoroborate. X-ray diffraction, scanning electron microscopy and transmission electron microscopy are used to characterize the morphology and crystalline structure of the microspheres. The as-synthesized SnO2 microspheres exhibit a tetragonal rutile structure. The mechanism of the microspheres formation is proposed. [Copyright &y& Elsevier]

A chelating bisoxime ligand, 2,2'-[(1,3-propylene)dioxybis(nitrilomethylidyne)]dinaphthol (H2L), and its corresponding Ni(II) cluster {[NiL(H2O)]2(OAc)2Ni} · 0.5MeOH · 0.5CH3CN · H2O (1) have been synthesized and characterized by elemental analyses, TG-DTA, IR, 1H NMR and X-ray diffraction methods. The Ni(II) cluster is monoclinic, space group P2(1)/c with cell dimensions a = 9.400(2), b = 24.530(4), c = 25.350(3) Å and β = 92.823(3)°. In the Ni(II) cluster, there are two ligand moieties (which provide N2O2 donors), two acetate ions and two water molecules, which result in three slightly distorted octahedral geometries around the Ni(II) ions. [ABSTRACT FROM AUTHOR]

Abstract: The Ag-exchanged commercial soda-lime silicate glasses were treated by three methods: thermal annealing, UV-laser irradiation, and X-ray irradiation, in order to promote the silver nanoclusters formation. Absorption spectrometry and electron spin resonance measurement results indicated that the silver ions transferred to silver atoms after the above three treatments. The silver atoms diffused and then aggregated to become nanoclusters after thermal annealing in air, or after UV-laser irradiation. However, X-ray irradiation, which induced defects and reduction of Ag0 atoms, would not promote the silver nanocluster formation. After annealing at 600°C for 45h, the spherical nanoclusters with a diameter of 3–8nm were formed. The nanoclusters with a diameter of about 2nm were formed after 30min UV-laser irradiation without subsequent heating. The surface plasmon resonance peak position of silver nanoclusters changed from 411nm after thermal annealing to 425nm after UV-laser irradiation. The peak position shift was due to the nanoclusters size difference. [Copyright &y& Elsevier]

Abstract: The synthesis of dimethyl carbonate by oxidative carbonylation of methanol using Cu salt catalysts in the presence of various room temperature ionic liquids (RTILs) was reported. Among the ionic liquids used, N-butylpyridinium tetrafluoroborate was the most effective promoter in terms of the conversion of methanol and the selectivity to dimethyl carbonate (DMC). The influences of reaction temperature, pressure, time, molar ratio of CO/O2, and amount of the ionic liquid on the oxidative carbonylation of methanol were investigated. The results indicated that under the reaction conditions of 120°C and 2.4MPa of a 2:1 mixture of CO and O2, 17.2% conversion of methanol, 97.8% selectivity of DMC and a DMC productivity of 4.6gg−1 cath−1 were achieved. The N-butylpyridinium tetrafluoroborate-meditated CuCl catalyst system could be reused at least five recycles with the same selectivity and a slight loss of catalytic activity due to loss of the catalyst during handling and transferring the reaction mixture. [Copyright &y& Elsevier]

Abstract: Oxygen treatment after KOH corrosion of phenolic-based activated carbon fibers was conducted to explore the influence of oxygen functional groups on the performance of capacitors fabricated with the carbon fibers. Scanning electron microscopy analysis shows that KOH corrosion can increase the surface roughness. The result of temperature programmed desorption shows that the amount of surface oxygen functional groups increases with the extent of oxygen treatment after KOH corrosion, and reaches a maximum at 250°C; the increase is contributed mainly by the formation of carbonyl- or quinone-type groups. The performance of the capacitors was tested in 7M KOH using potential sweep cyclic voltammetry and constant current charge–discharge cycling. The results reveal that the specific capacitance increases from 163.5Fg−1 to 280.7Fg−1 at a current density of 50mAg−1 with increasing the amount of oxygen functional groups. The oxygen functional groups can improve the wet ability of carbon surface and causes the quick faradic charge transfer reaction, which decreases the total resistance, and results in the enhancement of specific capacitance at high current density. [Copyright &y& Elsevier]

Manufacturing the glass–ceramic has been proposed as a useful choice to recycle coal fly ash from power plants. In this work, a glass–ceramic of SiO2–Al2O3–Fe2O3–CaO family was synthesized by mixing 90wt% of coal fly ash, from a power plant in west of China, with Na2O, and then melted at 1350°C. The ceramization of the obtained glass was carried out at 770°C for 2h. Esseneite and nepheline were found present as major crystal phases. The produced glass–ceramic exhibited good chemical durability as well as good mechanical properties. The toxicity characteristic leaching procedure (TCLP) method found that the glass–ceramic was non-hazardous. [Copyright &y& Elsevier]

A novel trinuclear nickel (II) cluster {[NiL(EtOH)]2(OAc)2Ni} · 2EtOH has been synthsized and characterized by elemental analyses, TG-DTA, IR and 1H-NMR etc. The X-ray crystallography of the cluster indicates that the ligand moieties of the cluster provide the N2O2 donors set to Ni2, while one oxygen atom of the μ-acetato and one oxygen atom of the ethanol molecule coordinate to Ni2, consequently forming a slightly distorted octahedral geometry. The double μ-acetato bridges adopt the more familiar μ O-C-O form which connect the Ni2-Ni1 and Ni1-Ni2#, respectively, so quadruple µ-phenoxo oxygens from 2 ligand moieties and double oxygen atoms from µ-acetato constitute another octahedral geometry. It is worthy noting that the distance from the Ni1 to Ni2 (3.089Å) is significantly longer than other coordination bond, shows a weaker interaction. In addition, the HOMO and LUMO levels of the cluster were deduced. [ABSTRACT FROM AUTHOR]

Abstract: Two Mn(II)–Au(I) supramolecular assemblies {{Mn[Au(CN)2]2(H2O)4} [Au(CN)2]2(H2bpy)·H2O}(bpy=4,4′-bipyridine) 1 and {Mn(4,4′-dmbpy) [Au(CN)2]2(CH3OH)} (4,4′-dmbpy=4,4′-dimethyl-bipyridine) 2 have been synthesized and magnetic properties have been investigated The interplay of aurophilicity, coordination, hydrogen-bonding and π–π interactions in two complexes result in three-dimensional network. [Copyright &y& Elsevier]

Abstract: Silver nanocluster formation and dissolution was observed in a soda-lime silicate glass with 0.02wt% of silver after X-ray irradiation followed by annealing. Absorption spectrometry and electron spin resonance measurement results indicated that the silver ions transferred to silver atoms after irradiation. The silver atoms diffused and then aggregated to become nanoclusters after annealing at high temperatures (such as >300°C). The nanoclusters grew during the first 15min at 420°C, and then slowly dissolved over a longer period. The mean nanocluster size estimated based on Mie theory was ∼4nm at 420°C for 1h, decreasing to ∼2nm after heating for 48h. The induced defects trapped electrons from silver nanoclusters, and the dissolution of silver nanoclusters to form silver ions results in a net loss in the system energy. The nanoclusters dissolved completely at 560°C for 1h. [Copyright &y& Elsevier]

Abstract: The microstructure evolution of phenolic fibers carbonized at different temperatures and the influence of the resulting microstructure on the mechanical and electrical behaviors were investigated using a combination of techniques including thermogravimetric analysis-mass spectroscopy (TG-MS), Fourier transform infrared spectroscopy (FT-IR), laser Raman spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 physical adsorption, tensile strength and electrical conductivity measurements. The results showed that below 500°C aromatic union was crosslinked by aliphatic bridges; above 500°C with increasing temperature the polymer network was destroyed, hexagonal carbon layers were gradually formed; above 850°C the content of the hexagonal carbon layers was further increased due to the transformation of the amorphous carbons in the fibers; above 1500°C slow evolution toward ideal graphite was occurred. The accessible micropores (<1.2nm, 200–1040m2/g) could be detected in the range of 600–950°C. The tensile strength of the carbon fibers exhibited a maximum value of 640MPa at 550°C. The electric conductivity increased with increasing temperature and reached a maximum value of 2.45×104 S/m at 2800°C. [Copyright &y& Elsevier]

A five-coordinate copper complex with the tripod ligand tris(1H-benzimidazol-2-ylmethyl)amine (ntb), of composition [Cu(ntb)(H2O)] (C1O4)2 · C5H4N2O3 · H2O (C5H4N2O3 = 4-nitropyridine-N-oxide), was synthesized and characterized by means of elemental analyses, electrical conductivities, thermal analyses, IR, and U.V. The crystal structure of the copper complex has been determined by single-crystal X-ray diffraction, and shows that the CuII is bonded to a tris(1H-benzimidazol-2-ylmethyl)amine (ntb) ligand and a water molecule through four N atoms and one O atom, giving a distorted trigonal-bipyramidal coordination geometry with approximate C3 molecular symmetry. Cyclic voltammograms of the copper complex indicate a quasi-reversible Cu+2/Cu+ couple. Electron spin resonance data confirm a trigonal-bipyramidal structure and with g2 < gζ and a very small value of A2 (20 × 10-4 cm-1). [ABSTRACT FROM AUTHOR]

A novel tri-nickel cluster, {[NiL]2(OAc)2Ni}, has been synthesized by the reaction of nickel(II) acetate tetrahydrate with a novel Salen-type bisoxime chelating ligand, 5,5'-Di(N,N'-diethylamino)-2,2'-[ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L). The X-ray crystal structure of the cluster reveals that two acetate ions coordinate to three nickel ions through Ni-O-C-O-Ni bridges and quadruple μ-phenoxo oxygen atoms from two [NiL] chelates also coordinate to nickel ion. Interestingly, the cluster possessing different conformational metal centers: five- and six-coordinated geometry. [ABSTRACT FROM AUTHOR]

A novel Cu(II) dimer, [CuL]2, has been synthesized by the reaction of H2L and Cu(CH3COO)2 · H2O with a 1:1 mole ratio in the mixed solvents of acetone and methanol, and characterized by elemental analysis, IR, TG-DTA etc., where H2L=4,4'-Dibromo-2,2'-[ethylenedioxybis(nitrilomethylidyne)]diphenol. The crystal structure was determined by single-crystal X-ray diffraction analysis. In one dimer molecule, the Cu:L is 2:2, and the coordination number of every copper(II) atom is five. [ABSTRACT FROM AUTHOR]

Abstract: A Prussian-blue analogue Mn3[Cr(CN)6]2·12H2O has been prepared and characterized by single crystal X-ray analysis and magnetic measurements. The complex has a disordered face-centered cubic lattice and shows two magnetic transition temperatures of 74 and 61K. [Copyright &y& Elsevier]

A novel tetradentate oxime chelating ligand, 3,3'-Dihydroxy-2,2'-[Ethylenedioxybis(nitrilomethyli-dyne)]diphenol (H4L), and its mononuclear copper(II) complex [Cu(H2L)] · 2H2O have been synthesized and characterized by elemental analysis, IR, UV-vis and 1H-NMR etc. The X-ray crystallography of complex [Cu(H2L)] · 2H2O indicates that the asymmetric unit consists of discrete [Cu(H2L)] and two crystallizing waters. The four atoms of the donor set (N1, N2, O1, O2) in the N2O2 coordination sphere and Cu1 approximately lie in a plane. The dihedral angle between the coordination plane of N(1)-Cu(1)-O(1) and that of N(2)-Cu(1)-O(2) is 16.6(8)°, indicating that the coordination environment is only slight distortion toward tetrahedral geometry from the square planar structure. The approximately hexagonal nanotube (10.412×4.989 Å) formed by the intermolecular hydrogen bonds in the central of the dimer were observed along the crystallographic b axis. [ABSTRACT FROM AUTHOR]

Abstract: A new conductive polyaniline derivative containing disulfide bonds, poly[bis(2-aminophenyloxy)disulfide] (PAPOD), has been proposed as a high energy-storage material. PAPOD has been synthesized using a moderate oxidant ferric chloride and characterized by elemental analysis, X-ray photoelectron spectroscopy (XPS), FT-IR, FT-Raman, and UV–vis spectroscopy. The cyclic voltammograms of this polymer show that the intramolecular self-catalysis occurs between the conductive main-chain polyaniline (doping/undoping processes of the π-conjugated system) and side-chain disulfide bonds (scission/reformation processes of the S–S bonds) in PAPOD. Because the redox reaction of conductive main-chain polyaniline occurs in the same potential range as that of the side-chain disulfide bonds of this polymer, the Li/PAPOD test cell displays a charge capacity of 230mAhg−1-cathode and an energy density of 460mWhg−1-cathode, which is about 2–3 times higher than those of inorganic intercalation compounds. [Copyright &y& Elsevier]

Abstract: Contraction and relaxation of cardiac muscle are regulated by the inhibitory and regulatory regions of troponin I (cTnI). Our previous FRET studies showed that the inhibitory region of cTnI in isolated troponin experiences a structural transition from a β-turn/coil motif to an extended conformation upon Ca2+ activation. During the relaxation process, the kinetics of the reversal of this conformation is coupled to the closing of the Ca2+-induced open conformation of the N-domain of troponin C (cTnC) and an interaction between cTnC and cTnI in their interface. We have since extended the structural kinetic study of the inhibitory region to fully regulated thin filament. Single-tryptophan and single-cysteine mutant cTnI(L129W/S151C) was labeled with 1,5-IAEDANS at Cys151, and the tryptophan-AEDANS pair served as a donor–acceptor pair. Labeled cTnI mutant was used to prepare regulated thin filaments. Ca2+-induced conformational changes in the segment of Trp129-Cys151 of cTnI were monitored by FRET sensitized acceptor (AEDANS) emission in Ca2+ titration and stopped-flow measurements. Control experiments suggested energy transfer from endogenous tryptophan residues of actin and myosin S1 to AEDANS attached to Cys151 of cTnI was very small and Ca2+ independent. The present results show that the rate of Ca2+-induced structural transition and Ca2+ sensitivity of the inhibitory region of cTnI were modified by (1) thin filament formation, (2) the presence of strongly bound S1, and (3) PKA phosphorylation of the N-terminus of cTnI. Ca2+ sensitivity was not significantly changed by the presence of cTm and actin. However, the cTn–cTm interaction decreased the cooperativity and kinetics of the structural transition within cTnI, while actin filaments elicited opposite effects. The strongly bound S1 significantly increased the Ca2+ sensitivity and slowed down the kinetics of structural transition. In contrast, PKA phosphorylation of cTnI decreased the Ca2+ sensitivity and accelerated the structural transition rate of the inhibitory region of cTnI on thin filaments. These results support the idea of a feedback mechanism by strong cross-bridge interaction with actin and provide insights on the molecular basis for the fine tuning of cardiac function by β-adrenergic stimulation. [Copyright &y& Elsevier]

Abstract: Four different system configurations with warm standby components and standby switching failures are compared based on their reliability and availability. The time-to-repair and the time-to-failure for each of the primary and warm standby components are assumed to follow the negative exponential distribution. We develop the explicit expressions for the mean time-to-failure, MTTF, and the steady-state availability, A T (∞), for four configurations. For all four configurations, comparisons are made for specific values of distribution parameters and of the cost of the components. The configurations are ranked based on MTTF, A T (∞), and cost/benefit where benefit is either MTTF or A T (∞). [Copyright &y& Elsevier]

The search for greater speed of analysis has fueled many innovations in high-performance liquid chromatography (HPLC), such as the use of higher pressures and smaller stationary-phase particles, and the development of monolithic columns. Alternatively, one might alter the chromatographic mobile phase. The low viscosity and high diffusivity of the mobile phase in supercritical fluid chromatography (SFC) allows higher flow rates and lower pressure drops than is possible in traditional HPLC. In addition, SFC requires less organic, or aqueous-organic, solvent than LC (important in preparative-scale chromatography) and provides an alternative, normal-phase retention mechanism. But fluids that are commonly used as the main mobile-phase component in SFC, such as C02, are relatively nonpolar. As a result, SFC is commonly believed to only be applicable to nonpolar and relatively low-polarity compounds. Here we build upon recent work with SFC of polar and ionic compounds and peptides, and we compare the LC/MS and SFC/MS of a diverse library of druglike compounds. A total of 75.0% of the library compounds were eluted and detected by SFC/MS, while 79.4% were eluted and detected by LC/MS. Some samples provided strong peaks that appeared to be related to the purported compound contained in the sample. When these were added to the ‘hits’, the numbers rose to 86.7 and 89.9%, respectively. A total of 3.7% of the samples were observed by SFC/MS, but not by LC/MS, and 8.1% of the samples were observed by LC/MS, but not by SFC/MS. The only compound class that appeared to be consistently detected in LC/MS, but not in SFC/MS under our conditions, consisted of compounds containing a phosphate, a phosphonate, or a bisphosphonate. The SFC/MS method was at least as durable, reliable, and user-friendly as the LC/MS method. The APCI source required less cleaning during the SFC/MS separations than it did during LC/MS. [ABSTRACT FROM AUTHOR]

A novel compound with the formula [Na2(H2O)10](NH4)3(NH3)[MoV9O28] has been synthesized for the first time and characterized by single crystal X‐ray diffraction, infrared spectrum, UV spectrum, element analysis and ICP analysis. The complex crystallizes in the triclinic space group P-1, with a=0.864 5(4) nm, b=1.044 8(4) nm, c=1.122 7(5) nm, α=69.245(6)°, β=87.224(6)°, γ=66.762(5)° and Z=1. The structure of the anion [MoV9O28]5- has a molybdenum atom mixing with nine vanadium atoms at certain positions in the similar backbone of the decanucleus structure. [ABSTRACT FROM AUTHOR]

The density functional theory (DFT) method has been used to investigate NO probe molecule adsorption on the stoichiometric (Mo16S32) and nonstoichiometric (Mo16S34and Mo16S29) clusters. The calculated adsorption energies indicate that the stoichiometric cluster has stronger NO affinity than the nonstoichiometric surfaces. It is also found that mononitrosyl adsorption is favored at low NO coverage, while dinitrosyl (germinal) and (NO)2dimer adsorption at high NO coverage are possible. Strong repulsive interaction has been found for the adsorbed dinitrosyl and (NO)2dimer species. In addition, the computed NO stretching frequencies for the mononitrosyl and dinitrosyl species agree well with the experimental data, while those of the dimer species are much lower than the suggested experimental data. [ABSTRACT FROM AUTHOR]

Many smart materials in bioengineering, nanotechnology and medicine allow the storage and release of encapsulated drugs on demand at a specific location by an external stimulus. Owing to their versatility in material selection, polyelectrolyte multilayers are very promising systems in the development of microencapsulation technologies with permeation control governed by variations in the environmental conditions. Here, organometallic polyelectrolyte multilayer capsules, composed of polyanions and polycations of poly(ferrocenylsilane) (PFS), are introduced. Their preparation involved layer-by-layer self-assembly onto colloidal templates followed by core removal. PFS polyelectrolytes feature redox-active ferrocene units in the main chain. Incorporation of PFS into the capsule walls allowed us to explore the effects of a new stimulus, that is, changing the redox state, on capsule wall permeability. The permeability of these capsules could be sensitively tuned via chemical oxidation, resulting in a fast capsule expansion accompanied by a drastic permeability increase in response to a very small trigger. The substantial swelling could be suppressed by the application of an additional coating bearing common redox-inert species of poly(styrene sulfonate) (PSS−) and poly(allylamine hydrochloride) (PAH+) on the outer wall of the capsules. Hence, we obtained a unique capsule system with redox-controlled permeability and swellability with a high application potential in materials as well as in bioscience. [ABSTRACT FROM AUTHOR]

Abstract: A 2D grid-like copper(II) complex [Cu(N3)2(pyz)](pyz=pyrazine) (1) has been synthesized and characterized by single crystal X-ray analysis and magnetic measurements. The 2D grid-like network of 1 consists of 1D chain of Cu-pyz units connected by end-on azido bridge. 1 crystallizes in the monoclinic space group C2 with a =15.148(6)Å, b =6.877(2)Å, c =3.4591(12)Å and Z =2. The magnetic investigation showed the presence of an antiferromagnetic interaction between the copper(II) ions mainly mediated through pyrazine bridge. [Copyright &y& Elsevier]

Abstract: Two novel 1D complexes, [Ni(hto){Au(CN)2}2][Ni(hto)](ClO4)2 ·4H2O (hto=1,3,6,9,11,14-hexaazatricyclo[12.2.1.16,9]octadecane, in Scheme 1.) (1) and [Co(dien)2][{Au(CN)2}3]·2H2O (dien=diethylenetriamine) (2) have been synthesized and characterized. The crystal structure of 1 confirmed the presence of nickel (II) chains via Au–Au interactions. The coordination geometry around the six-coordinate nickel (II) ion is slightly distorted octahedral with four nitrogen atoms of the macrocycle and two nitrogen atoms of the cyanides. The presence of Au–Au interactions have effectively increased the zero dimensional coordination polymer to a one dimensional system. In the complex 2, there are one cation, three anions, and two water molecules in the asymmetric unit. These components are interconnected through a combination of aurophilic attractions and hydrogen bonds and formed 1D chains. [Copyright &y& Elsevier]

A cyano-bridged nickel(II) compound, {[Ni(hto)][Ni(CN)4]·(i-C3H7OH)·2H2O}n(hto=1,3,6,9,11,14-hexaazatricyclo[12.2.1.16,9]octadecane, in Scheme 1), has been prepared and characterized. Single crystal X-ray analysis reveals that the compound assumes a one-dimensional structure in which one nickel(II) ion is coordinated by four cyanide ligands and the other is coordinated by four nitrogen atoms of the macrocyclic ligand and two nitrogen atoms of the bridging cyanide ligands. The six-coordinate nickel(II) centres display an axially elongated octahedron, whereas the four-coordinate nickel(II) centres assume planar geometry. The polar guest isopropanol and water molecules are accommodated among [–Ni(hto)–NC–Ni(CN)2–CN–]n chains. The interguest and host–guest hydrogen-bonds formation link the chains and stabilize the whole crystal structure. [Copyright &y& Elsevier]

The principal task of the Ca2+ activation of striated muscle is the release of the troponin I (TnI) inhibitory region (TnI-I) from actin. TnI-I release facilitates the repositioning of tropomyosin across the actin surface and the formation of strong, force generating, actin-myosin cross-bridges. Full activation of the Ca2+ regulatory switch (CRS) requires two switching steps in cTnI: binding of the TnI regulatory region to hydrophobic sites in the N-domain of Ca2+-bound troponin C and release of the adjacent TnI-I from actin. Using Förster resonance energy transfer, we have examined the requirements for full activation of the cardiac CRS. In the presence of actin, both Ca2+ and strong cross-bridges are required for full activation. Actin desensitizes the CRS to Ca2+ and produces cooperativity in the Ca2+ activation of the CRS. Strong cross-bridges eliminate cooperativity and re-sensitize the CRS to Ca2+. We propose a kinetic scheme and a structural model to account for these findings. [Copyright &y& Elsevier]

In experiments reported here, we compared tension and thin filament Ca2+ signaling in preparations containing either wild-type cardiac troponin I (cTnI) or a mutant cTnI with an R146G mutation [cTnI(146G)] linked to familial hypertrophic cardiomyopathy. Myofilament function is altered in association with cTnI phosphorylation by protein kinase C (PKC), which is activated in hypertrophy. Whether there are differential effects of PKC phosphorylation on cTnI compared to cTnI(146G) remains unknown. We therefore also studied cTnI and cTnI(146G) with PKC sites mutated to Glu, which mimics phosphorylation. Compared to cTnI controls, binary complexes with either cTnI(146G) or cTnI(43E/45E/ 144E) had a small effect on Ca2+-dependent structural opening of the N-terminal regulatory domain of cTnC as measured using Förster resonance energy transfer. However, this structural change was significantly reduced in the cTnC-cTnI(43E/45E/144E/146G) complex. Exchange of cTnI in skinned fiber bundles with cTnI(146G) induced enhanced Ca2+ sensitivity and an elevated resting tension. Exchange of cTnI with cTnI(43E/45E/144E) induced a depression in Ca2+ sensitivity and maximum tension. However, compared to cTnI(146G), cTnI(43E/45E/144E/146G) had little additional effects on myofilament response to Ca2+ By comparing activation of tension to the open state of the N-domain of cTnC with variations in the state of cTnI, we were able to provide data supporting the hypothesis that activation of cardiac myofilaments is tightly coupled to the open state of the N-domain of cTnC. Our data also support the hypothesis that pathological effects of phosphorylation are influenced by mutations in cTnI. [ABSTRACT FROM AUTHOR]

Three novel dicyanamide complexes {[Ni(μ1,5-dca)(pn)](ClO4)}n (I), [Mn(μ1,5-dca)2(phen)]n (II) and [Mn(μ1,5-dca)2L]n (III) have been synthesized and structurally characterized. Complex I forms 1-D chain and II forms 2-D layer structure, which are both bridged via μ1,5-dca ligands. Whereas complex III contains 3-D networks bridging via μ1,5-dca and 4,4′-ditriazole methane ligands. The magnetic measurements indicate that all these complexes exhibit weak antiferromagnetic interaction through the five-atom [NCNCN]− bridging ligands, with J=−6.3, −1.3 and −1.1 cm−1 for complex I, II and III, respectively. [Copyright &y& Elsevier]