Structural and Spectral Studies of Some Geometric Isomers of N-Pivaloyl-Nˊ-dichlorophenyl Thiourea

N-pivaloyl-Nˊ-（3,4-dichlorophenyl）thiourea （1）： monoclinic, P21/a, a=11.57（1）, b=9.278（8）, c=13.51（1）, β=103.85（1）°, V=1408（2）3 , Z=4, μ=0.598 mm-1 ; N-pivaloyl-N＇-（3,5- dichlorophenyl）thiourea （2）： monoclinic, P21/a, a=7.176（2）, b=16.441（4）, c=11.923（2）, β=92.48（1）°, V=1405.3（6）3 , Z=4, μ=0.600 mm-1 ; N-pivaloyl-Nˊ-（2,6-dichlorophenyl）thiourea （3）： orthorhombic, Pnma, a=26.79（1）, b=8.780（4）, c=5.955（3）, V=1400.7（11）3 , Z=4, μ=0.601 mm-1 . All three complexes have an intramolecular hydrogen bond between NˊH and the carbonyl oxygen. Solution 1H NMR studies （CDCl3） show the NH resonance considerable downfield for each thiourea and their positions, as well as that of NH, is affected by substituents on the phenyl ring.

Analytical, Spectral, Thermal and Molecular Modeling Studies of Hg2+-2,3-Butanedionemonoxime Girard’s T Hydrazone Complex and Its Application

The coordination behavior of 2,3-butanedionemonoxime Girard’s T hydrazone (L1) towards Hg2+ ion has been investigated. The structure of Hg2+ complex, [Hg(L1)Cl]Cl·5H2O, is elucidated using elemental analyses, spectral (IR, UV-visible, 1H-NMR and mass) and TGA measurements. IR spectrum suggests that L1 behaves in a bidentate manner through the azomethine groups. The molecular modeling of L1 and its Hg2+ complex has been investigated. The bond lengths, bond angles, HOMO and LUMO have been calculated. The thermal behavior and kinetic parameters are determined using Coats-Redfern method. The use of L1 for preconcentration and separation via flotation of Hg2+ complex and determination using cold vapor atomic spectrometry (CVAAS) is described. The effects on the percentage of recovered Hg2+ by pH of sample solutions, oleic acid (HOL) concentration, Hg2+ and L1 concentrations are studied in details. The method is applied for the determination of the total Hg2+ (mg·mL-1) in natural water samples.

Studies on the Growth and Characterization of L-Arginine Maleate Dihydrate Crystal Grown from Liquid Diffusion Technique

Nonlinear optical crystals of L-Arginine maleate dihydrate were grown from liquid diffusion method. The lattice parameters of the crystal were identified using single crystal and powder crystal X-ray diffraction analyses. Fourier transform infrared spectroscopy and Fourier transform Raman spectroscopy were made to study the vibrational functional groups in the grown crystal. Optical absorption and transmission ranges were measured from UV-VIS-NIR spectrum. The molecular structure of the crystal is established through 1H-NMR and 13C-NMR studies. Thermal stabilities and decomposition of the grown crystal were studied from TG/DTA and DSC analyses. Nonlinear optical property of the crystal was determined by Kurtz and Perry powder technique.

SPECTRAL STUDY ON A NEW 3d_z^2 TYPE COPPER(Ⅱ)COMPLEX OF PHENOLIC POLYMERIC CROWN ETHER

ESR and IR measurements have been carried out for a copper(Ⅱ)complex of phenolic polymeric crown ether,As a result,the triplet ESR spectrum(S=1)of 3d_z2 ground state copper(Ⅱ)ions was first observed for the powder sample.It indicated that there existed intramolecular spin-spin interaction betweeen 3d_Z2 ground state copper(Ⅱ)and copper(Ⅱ)ions.In this binuclear triplet cluster,the axial ligntion of one water molecule in a sandwich position to two adjacent copper(Ⅱ) ions was also confirmed by IR spectra,All things considered,a possible structure for the complex was proposed.

SPECTRAL CHARACTERISTICS OF ELECTRORETINOGRAM IN X-LINKED DICHROMATS-A PRELIMINARY STUDY

Spectral characteristics of X-linked Dichromats(13 protanopes, 20 deuteranopes) were studied with spectral ERG. The results are as follows: The maximal spectral response of the b-wave in protanopes tended to shift toward the short wavelength side and the sensitivity to long wavelengths decreased obviously. The ratio value of the amplitude in 500nm and in 620nm(500/620) was greater in the protanope than that in the normal subject. Like the normals, the maximal response of the b-wave in deuteranopes appea...

Chemical Constituents from Caesalpinia férrea:Identification and ^(1)H and ^(13)C Resonance Assignment

In a phytochemical investigation of Caesalpinia ferrea (Leguminosae), four aromatic compounds (1-4) have been isolated and identified. Their structures have been assigned based on data provided by spectroscopic techniques, including 2D NMR experiments. Compounds 3 and 4 are being reported for the first time for Cesalpina ferrea.

Preparation and Properties of the Heteropolyoxometalates of Large Organic Cation with Molybdotungstosilicic Acids

Some new heteropolyoxometalates of large organic cations with molybdotungstosilicic acids （general formula： （CTMA）4SiMoxW12-xO40·mH2O·nDMF, x=0,2,4,6,8,10,12） were prepared by the reaction of cetyltrimethylammonium bromide （CTMAB,C16H33N（CH3）3Br） with H4SiMoxW12-xO40（x=0,2,4,6,8,10,12） in aqueous solution and recrystallization in DMF, and characterized by elemental analysis, IR spectra,TG- DTA and XRD techniques. The IR spectrum confirms the presence of Keggin structure and organic cations in these compounds, and it is indicated that the stretching vibration of the M-Od, M-Ob-M and Si-Oa becomes more red-shifted when molybdenum is gradually substituted for the tungsten atom. In particular, the thermal decomposition of the heteropolyoxometalates was studied in nitrogen atmosphere. The TG-DTA curves show that their thermal behaviors not only contain the release of water molecule, DMF molecule, CTMA and its fragments but also contains simultaneous collapse of Keggin anion. Their end products of the thermal decomposition are the mixture of WO3, MoO3 and SiO2. And from the final decomposition temperature of view, it is found that the thermal stability of these compounds gradually is decreased when the number of molybdenum atoms is increased.

Study on the key technology of spectral reflectivity reconstruction based on sparse prior by a single-pixel detector

By studying the traditional spectral reflectance reconstruction method, spectral reflectance and the relative spectral power distribution of a lighting source are sparsely decomposed, and the orthogonal property of the principal component orthogonal basis is used to eliminate basis; then spectral reflectance data are obtained by solving a sparse coefficient. After theoretical analysis, the spectral reflectance reconstruction based on sparse prior knowledge of the principal component orthogonal basis by a single-pixel detector is carried out by software simulation and experiment. It can reduce the complexity and cost of the system, and has certain significance for the improvement of multispectral image acquisition technology.

Preparation, Characterization, Biological Activity and 3D Molecular Modeling of Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） Complexes of Some Sulfadrug Schiff Bases

Mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） complexes of Schiff bases derived from the condensation of sulfaguanidine with 2,4-dihydroxy benzaldehyde （HL1）, 2-hydroxy-l-naphthaldehyde （HL2） and salicylaldehyde （HL3） have been synthesized. The structures of the prepared metal complexes were proposed based on elemental analysis, molar conductance, thermal analysis （TGA, DSC and DTG）, magnetic susceptibility measurements and spectroscopic techniques （IR, UV-Vis, and ESR）. In all complexes, the ligand bonds to the metal ion through the azomethine nitrogen and a-hydroxy oxygen atoms. The structures of Pd（Ⅱ） complex 8 and Ru（Ⅲ） complex 9 were found to be polynuclear. Two kinds of stereochemical geometries; distorted tetrahedral and distorted square py- ramidal, have been realized for the Cu（Ⅱ） complexes based on the results of UV-Vis, magnetic susceptibility and ESR spectra whereas octahedral geometry was predicted for Co（Ⅱ）, Mn（Ⅱ） and Ru（Ⅲ） complexes. Ni（Ⅱ） com- plexes were predicted to be square planar and tetrahedral and Pd（Ⅱ） complexes were found to be square planar. The antimicrobial activity of the ligands and their metal complexes was also investigated against the gram-positive bac- teria Staphylococcus aures and Bacillus subtilis and gram-negative bacteria, Escherichia coli and Pesudomonas aeruginosa, by using the agar dilution method. Chloramphenicol was used as standard compound. The obtained data revealed that the metal complexes are more or less, active than the parent ligand and standard. The X-ray crys- tal structure of HL3 has been also reported.

Parametric study of a new HOS-CFD coupling method

This paper presents a developed new coupled method which combined our in-house CFD solver naoe-FOAM-SJTU and naoe-FOAM-os with a potential theory High Order Spectral method(HOS).A parametric study of nonlinear wave propagation in computational fluid dynamics(CFD)zone is considered.Mesh convergence,time step convergence,time discretization scheme and length of relaxation zone are all carried out.Those parametric studies verify the steady of this new combined method and give better choice for wave propagation.The dissipation in propagation of nonlinear regular wave can be lower than 3%in static mesh,and less than 2%in overset grid mesh.Meanwhile,a LNG FPSO is put into the viscous wave tank to study the suitable size of CFD zone.To achieve a better solution with least calculating resources and best numerical results,the length of CFD zone is discussed.These parametric studies can give reference upon employment of the potential-viscous coupled method and validation of the coupled method.