A Novel 2D Architecture from Bismuth and Flexible Ligand N,N'-Diacetic Acid Imidazolium Chloride

A new compound {[Bi（trans-DAM）（cis-DAM）（H2O）]NO3·H2O}n 1 derived from bismuth and the flexible ligand N,N＇-diacetic acid imidazolium chloride （H2DAMCl） was obtained by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic P21/c space group with a = 9.2298（18）, b = 13.339（3）, c = 17.090（3） , β = 105.38（2）°, V = 2028.7（7）A^3, Z = 4, C14H18N5O13Bi, Mr = 673.31, Dc = 2.204 g/cm^3, F（000） = 1296, μ = 8.772 mm-1, the final R = 0.0472 and wR = 0.1441 for 4129 observed reflections （I 〉 2σ（I））. In 1, the carboxylic groups from DAM- ligands adopt a cheating mode to link bismuth ions to form a 2D sheet network. These sheets are further connected by hydrogen bonding interactions to give an interesting 3D supramolecular framework. 2D correlation analysis of IR of 1 with thermal and magnetic perturbation was introduced to ascertain the characteristic adsorption of the groups overlapped in the 1D IR spectrum. Additionally, compound 1 exhibits fluorescent emission at room temperature.

USING TWO-DIMENSIONAL TIME RESOLVED LIGHT SCATTERING TO STUDY THE CURE REACTION INDUCED PHASE SEPARATION PROCESS OF EPOXY-AMINE-POLYETHERSULFONE BLEND WITH SECONDARY PHASE SEPARATION

The generalized two-dimensional correlation analysis based on time-resolved light scattering patterns （2D TRLS） has been employed to study the phase separation process of an epoxy-amine-polyethersulfone blend in which the secondary phase separation takes place. The results of the 2D TRLS provided more detailed information that was not readily observed in the 1D TRLS patterns. （i） During the first process of phase separation, the sequential order of coarsening in size of the domains among the larger and smaller ones has been reversed between the diffusion regime and the hydrodynamic regime. （ii） The change of the larger domains in size, due to the hydrodynamic flow in the late stage of the first phase separation process, keeps on taking place earlier than that of the new domains appeared in the secondary phase separation process. （iii） During the secondary phase separation process the size growth of the smaller domains takes place earlier than that of the larger ones, probably due to the assumption that the coarsening mode could decrease the interface tension more quickly.

A Porous Organic-inorganic Hybrid Compound Constructed from Polyoxovanadium Borate Anions,Dinuclear Na Sites and Metal-organic Units

A polyoxovanadium borate [Na（H2O）]2[Na（H2O）2]2[Cu（en）2][V12B18O54（OH）6]·（H3O）2·（H2O）18 1（en = ethylenediamine） has been hydrothermally synthesized and characterized by IR,two-dimensional infrared（2D IR） correlation spectroscopy with magnetic and thermal perturba-tion,thermal IR spectroscopy,thermal gravimetric analysis and single-crystal X-ray diffraction.It crystallizes in triclinic,space group P with a = 12.981（3）,b = 13.044（3）,c = 14.208（3） ,α = 63.98（3）,β = 77.17（3）,γ = 14.208（3）°,V = 2001.0（8） 3,Z = 1,Mr = 2518.05,Dc = 2.090 g/cm-1,F（000） = 1255.0,Mu（mm-1） = 1.756,λ（MoKα） = 0.71073 ,R = 0.0625 and wR = 0.1952.In 1,the [V12B18O54（OH）6]8- units are connected by [Cu（en）2]2＋,binuclear Na（1） and Na（2） to form a three-dimensional porous framework.

pH-induced structural changes of surface immobilized poly (L-lysine) by two-dimensional (2D) infrared correlation study

This paper reports the pH-induced structural changes in the surface immobilized poly（L-lysine）（PLL）film.Two-dimensional（2D） correlation analysis was applied to the Fourier transform infrared（FTIR）spectra of the surface-immobilized PLL film to examine the spectral changes induced by the alternations of the protonation state of the amino group in the side chain.Significant spectral changes in the FTIR spectra of the PLL film were observed between pH 7 and 8.The decrease in the protonation state of the amino group in the side chain induced spectral changes in the amino group as well as conformational changes in the alky]group in the side chain.From pH 1-8,the spectral changes in the amino and alkyl groups in the side chain occurred before those of the amide group in the main chain of the surface immobilized PLL film.

Application of 2D fluorescence correlation method to investigate the dilution-induced heterogeneous distribution of the bound FMN in azoreductase

AzoR is a homodimeric,flavin mononucleotide（FMN）-containing,NADH-dependent azoreductase from Escherichia coli.In this paper,we investigated the effect of the concentration of both AzoR and R59 G on the spectral behavior of the bound FMN using two-dimensional fluorescence correlation spectra.Two cross peaks（530,490） and（580,530） were observed from the dilution-induced 2D asynchronous correlation map of wt AzoR,while only one cross peak appeared at（600,530） for R59 C mutant.This result indicated that the mutation at site 59 influenced the formation of dilution-induced intermediates.The specific activity of both AzoR and R59 G mutant was unaffected by dilution when the enzyme concentration is below 1 μmol/L,which suggested that no significant dissociation of FMN occurred at low concentrations.Additionally,in order to explore the origin of these intermediates,we carried out a2 D correlation analysis using excitation wavelength-dependent fluorescence emission spectroscopy.The results showed that there coexisted two types of FMN that emitted fluorescence at 530 nm and 500 nm,respectively.Taken together,these results suggested that the 2D method is a very powerful method to identify the heterogeneous distribution of the bound FMN in solution.

Two-dimensional correlation spectroscopic studies on coordination between carbonyl group of butanone and metal ions

Two dimensional asynchronous spectra were used to characterize coordination between carbonyl group of butanone and metal ions by using an approach proposed in our recent paper.Spectral variation of n-π^＊transition band of carbonyl group is used to probe the coordination even if metal ions does not possess any characteristic peak in spectra.Experimental results indicate that Ca^2＋ and Al^3＋ show considerable ability to coordinate with the carbonyl group of butanone and bring about spectral variation of the n-π-＊transition band,which is manifested by cross peaks in 2D asynchronous spectra.

Synthesis and characterization of a new catalyst for RhB degradation constructed by[SiMo_(12)O_(40)]^(4-) anionic cluster

A Keggin-type polyoxomolybdate[H2biim]{Ni（biim）3（SiMO12O40）}[biim =1H,1＇H-[2,2＇]biimidazolyl]has been synthesized under hydrothermal condition and characterized by XRD,temperature-dependent IR,TG,temperature-induced and magnetism-induced 2D infrared correlation spectroscopy（2D-IR COS）and UV-vis DRS in order to explore the relationship between structure and properties.Temperatureinduced 2D-IR COS spectroscopy indicates that the terminal Mo-Oμ/υbonds are more sensitive than the bridging Mo=Ot,bands to temperature variation,which is in agreement with the conclusion of temperature-dependent IR.Magnetism-dependent 2D-IR COS spectroscopy reveals the stretching vibration of the Mo=Ot,occurs prior to the stretching vibration of the Mo-Oμ/υ,which is due to the coordination environment and the valence of the Si atom.The stability of compound 1 is investigated via TG and temperature-dependent IR.In RhB degradation,compound 1 shows good photocatalytic abilities.

Adsorption of arsenate on lanthanum-impregnated activated alumina:In situ ATR-FTIR and two-dimensional correlation analysis study

Lanthanum modified materials have been widely used for the removal of hazardous anions.In this study,in situ ATR-FTIR and two-dimensional correlation analysis were employed to investigate the adsorption mechanism of arsenate（As（V）） on lanthanum-impregnated activated alumina（LAA）.Our results showed that electrostatic interaction attracted As（V） anions to the LAA surface,and then As（V） could form monodentate configuration on the LAA surface at pH 5-9.The result of 2D-COS showed that two coexistent adsorbed As（V） species,H2AsO4^- and HAsO4^2-,were adsorbed on the LAA surface without specific sequence at different pH conditions,indicating a negligible role of the incorporated protons of As（V） on the adsorption affinity to LAA surface.The results of this study reveal insights into LAA surface complexes on the molecular scale and provide theoretical support to new metal oxides design for efficient arsenic removal.