Existence and global attractiveness of a pseudo almost periodic solution in p-th mean sense for stochastic evolution equation driven by a fractional Brownian motion

In this work, we establish a new concept of pseudo almost periodic processes in p-th mean sense using the measure theory. We use the μ-ergodic process to define the spaces of μ-pseudo almost periodic process in the p-th mean sense. We establish many interesting results on the functional space of such processes like completeness and composition theorems. The main objective of this paper is to use those results and some stochastic analysis approaches to study the existence, the uniqueness and the global attractiveness for a μ-pseudo almost periodic mild solution to a class of abstract stochastic evolution equations driven by fractional Brownian motion. We provide an example to illustrate our results.     

Platinum(II) complex-catalyzed enantioselective aldol reaction with ketene silyl acetals in DMF at room temperature

[{(R)-binap}Pt(μ-OH)]₂2X is a weak Lewis acid, which can catalyze the enantioselective aldol reaction of aldehydes with ketene silyl acetals in DMF at room temperature. The platinum(II) complex-catalyzed the enantioselective aldol reaction of aldehydes with 1-methoxy-2-methyl-(1-trimethylsilyloxy)propene gave the corresponding aldols in high yields with enantioselectivity up to 92%. With 5 mol % loading of the complexes, the enantioselective aldol reaction of aldehydes with 1-benzyloxy-1-(trimethylsilyloxy)propene smoothly proceeded in DMF containing 10% HMPA as to predominantly give anti-propionates with enantioselectivity up to 89%, irrespective of the silyl nucleophile geometry.     

Adsorptive micro-extraction techniques--novel analytical tools for trace levels of polar solutes in aqueous media

A novel enrichment technique, adsorptive μ-extraction (AμE), is proposed for trace analysis of polar solutes in aqueous media. The preparation, stability tests and development of the analytical devices using two geometrical configurations, i.e. bar adsorptive μ-extraction (BAμE) and multi-spheres adsorptive μ-extraction (MSAμE) is fully discussed. From the several sorbent materials tested, activated carbons and polystyrene divinylbenzene phases demonstrated the best stability, robustness and to be the most suitable for analytical purposes. The application of both BAμE and MSAμE devices proved remarkable performance for the determination of trace levels of polar solutes and metabolites (e.g. pesticides, disinfection by-products, drugs of abuse and pharmaceuticals) in water matrices and biological fluids. By comparing AμE techniques with stir bar sorptive extraction based on polydimethylsiloxane phase, great effectiveness is attained overcoming the limitations of the latter enrichment approach regarding the more polar solutes. Furthermore, convenient sensitivity and selectivity is reached through AμE techniques, since the great advantage of this new analytical technology is the possibility to choose the most suitable sorbent to each particular type of application. The enrichment techniques proposed are cost-effective, easy to prepare and work-up, demonstrating robustness and to be a remarkable analytical tool for trace analysis of priority solutes in areas of recognized importance such as environment, forensic and other related life sciences.     

Photo- and radio-excited luminescence properties of Eu-doped La2O3–Al2O3 based eutectics

Eutectic crystal of 0.5% Eu-doped 30LaAlO₃–70Al₂O₃ (vol %) was prepared by micro-pulling down (μ-PD) technique under nitrogen atmosphere. Being excited at a wavelength of 320 nm, the crystal exhibited intense emission band with a maximum at 450 nm which is corresponding to 4f⁶5d-4f⁷(⁸S_7/2) transitions of Eu²⁺. The decay time and fluorescence quantum efficiency (QE) were determined to be about 475 ns and 60%, respectively. When alpha-ray excited the crystal, both Eu²⁺ 4f⁶5d-4f⁷(⁸S_7/2) and Eu³⁺ 4f⁶-4f⁶ (⁵D₀-⁷F_1,2) emission peaks were observed at 435 nm and 600 nm. By the pulse height spectra, the relative scintillation light yield of the crystal was about 4% compared with that of BGO commercial scintillator.     

μ-Synchrotron radiation excited X-ray fluorescence microprobe trace element studies on spherules of the Cretaceous/Tertiary boundary transitions of NE-Mexico and Haiti samples

Synchrotron radiation, collimated to a μm scale was used for the determination of trace elements in micro-tektites and spherule material for the first time. The experimental set-up of the SXRF microprobe at beamline L at HASYLAB at DESY offers a suitable method for performing non-destructive in situ multi-element analysis focusing on spatial trace element distributions and mineral phases of the melted ejecta material from the Cretaceous/Tertiary boundary. The spatial distribution of trace elements was determined in melt inclusions as well as in phase transitions in selected parts of chlorite–smectite spherules and tektite glass material by using a beam with a diameter of 15 μm collimated with a glass capillary for line- and area scans as well as for single point measurements for elements with Z between 19 and 92. The analyzed spherules show alteration features but also zonation and carbonate inclusions, originating from the Chicxulub impact event. These initial results demonstrate the potential of μ-SXRF analysis for the discrimination of alteration and primary signals of the spherules and re-construction of their genetic evolution. It could be shown that the spherules represent a complex mixture of different materials from the subsurface at the Chicxulub impact site.     

Crystal Structure of Bridged Dimer Complex of [Yb (H_2O)) (acac)_2 (Ac)]_2

1INTRODUCTIONTheacetylacetonatoisanexcellentbidentateligand.Withittherareearthmetalionscanformsomeseriesofcomplexes,suchasLn(acac)3.nH,O(n=1～4)andLn-(acac)4etc.[1-5i.lntheeventletasampleofthecomplexLn(acac)3.3H,Odis-solveinacetylacetonewhichmixeswithaceticacidforrecrystallization.Asaresultasubstitutionreactionofligandsinthesolutionarises.Anacetylacetonatoandacoor-dinatedwatermolecu1eofLn(acac),.3H,Oaresubstitutedbytwoacetatosandanon-coordinatedwatermoleculeisremoved.Amixedligandandbr…     

Reaction of [P3N3Cl4(NH2)2] with [HN(POCl2)2]; The crystal structure of the phosphazenium salt [P3N3HCl4(NH2)2]+[N(POCl2)2]−

The reaction of diaminotetrachloro-cyclotriphosphazene with tetrachloride of μ-imino-diphosphoric acid leads to the formation of the salt-like compound [P₃N₃HCl₄(NH₂)₂]⁺[N(POCl₂)₂]⁻ which identity was unambiguously established by means of X-ray structure analysis. The structure is composed of [P₃N₃HCl₄(NH₂)₂]⁺ cations and [N(POCl₂)₂]⁻ anions joined by a system of H-bonds. As in other phosphazenium salts, the protonation of the ring N atom leads to significant changes in the endocyclic P N bond lengths.     

甲基丙烯酸酯毛细管整体柱分离微囊藻毒素的研究

以甲基丙烯酸丁酯为单体,乙二醇二甲基丙烯酸酯为交联剂,在致孔剂存在的条件下原位聚合制备了甲基丙烯酸丁酯毛细管整体柱(150 μm i.d.)。实验中优化了用此整体柱分离3种微囊藻毒素(MC-LR,-YR和-RR)的色谱条件(流动相种类、缓冲溶液浓度、pH、流动相流速),建立了微囊藻毒素的整体柱毛细管液相色谱分离方法,该法可以在9 min之内实现3种微囊藻毒素的基线分离。将该方法应用于实际水样中微囊藻毒素的分析,成功实现了培养水样和巢湖水样中微囊藻毒素的快速分离,两种样品中均检测到MC-LR。结果表明,所制备的甲基丙烯酸酯毛细管整体柱具有良好的重现性、渗透性,在微囊藻毒素的常规检测中具有很好的应用前景。     

Synthesis and Crystal Structure of the Ladder-like Organotin Complex: μ-pentaoxygen bridged penta(bis-benzyltin) bis-salicylate

A novel organotin complex of μ-pentaoxygen bridged penta(bis-benzyltin) bis- salicylate has been synthesized by the reaction of bis-benzyltin oxide and salicylic acid and its struc- ture has been determined by X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 1.7206(5), b = 2.1401(6), c = 2.1488(6) nm, β = 93.325(5)o, V = 7.899(4) nm3, Z = 4, Dc = 1.564 g/cm3, μ(MoKα) = 16.17 cm-1, Mr = 1859.94, F(000) = 3692, R1 = 0.0755 and wR2 = 0.1557. According to structural analysis, the coordination geometry of tin is a distorted trigonal bipyramid, and the ladder-like structure is shaped by four Sn2O2 planar four-membered rings.