Co-Precipitation Synthesis and Spectral Characteristics of Long Afterglow Phosphor Y_2O_2S:Sm^(3+), Mg^(2+), Ti^(4+)

Y2O2S：Sm^3＋, Mg^2＋, Ti^4＋ phosphor was synthesized by co-precipitation method. The crystalline structure of all synthesized phosphors was investigated by XRD. The result showed that all synthesized phosphors had a hexagonal crystal structure, which was the same as Y2O2S. The emission spectrum and excitation spectrum were measured, and the effect of Sm^3 ＋ molar ratio on the spectra was discussed. The emission spectra of the phosphors showed three emission peaks due to typical transitions of Sm^3 ＋ （4G5/2→6HJ ,J = 5/2, 7/2, 9/2）, and the emission peaks at 606 nm was stronger than others. With the increase of Sm^3 ＋ molar ratio, the emission intensity was strengthened. The excitation peaks were ascribed to the representative energy transition 4f→4f of Ti^4＋ phosphor prepared by co-precipitation method was Sm^3＋ ions. The results indicated that the Y2O2S ： Sm^3＋ , Mg^2＋ , an efficient long afterglow phosphor.

Autler-Townes splitting in photoelectron spectra of K_2 molecule

We investigate Autler-Townes splitting in the photoelectron spectra of K2 molecule driven by pump-probe pulses via employing the time-dependent wave packet approach. It is found that the magnitude of Aulter-Townes splitting varies with the wavelength of the intense laser pulse. In particular, the phenomenon of Aulter-Townes splitting vanishes for the far-off resonance of the pump pulse. Also, the split peaks of Autler Townes in the case of resonant pump pulse give us an approach to directly obtaining the transition dipole moment of a molecule.

Synthesis and Infrared Spectra Computation of Sterically Congested 2,2-Disubstituted Indane-1,3-dione Derivatives

Sterically congested 2,2-disubstituted indane-1,3-dione derivatives have been syn-thesized and characterized by 1H NMR,13C NMR,FT-IR and elemental analysis.The B3LYP/HF calculations for computation of IR spectra have been carried out for the title compounds at the 6-31G and 6-311＋＋G basis set levels.Predicted vibrational frequencies have been assigned and compared with the experimental FT-IR spectra and they are supported each other.

金盏菊原生质体对土壤铅/镉响应机制的FTIR,2D-IR和XPS证据

土壤修复是“十四五”期间国家重点支持的环保领域,是实现社会可持续发展的重要保障。与其他方法相比,植物修复技术整体优势突出,对于土壤重金属的去除净化更为有效。原生质体是植物细胞代谢活动的重要场所,相对于细胞壁而言,原生质体对重金属胁迫的生理响应同样强烈。现阶段,同类植物修复机制研究多从分子生物学层面切入;本研究则从谱学角度展开,初步探究植物原生质体对土壤重金属的反馈信号。以代表性的菊科植物金盏菊为研究对象,通过Pb/Cd胁迫盆栽实验获取金盏菊样本,差速冷冻离心法得到金盏菊原生质体。引入Tessier连续提取-原子吸收光谱法(AAS)揭示胁迫强度与Pb/Cd赋存形态的内在关联,结合X射线衍射光谱(XRD)、傅里叶变换红外光谱(FTIR)、二维相关红外光谱(2D-IR)和X射线光电子能谱(XPS)识别金盏菊原生质体对Pb/Cd响应的谱学表现。结果表明:金盏菊原生质体可交换态Pb/Cd比例不高,胁迫强度对不同形态Cd含量影响很小。XRD图谱最强信号出现在31.7°(NaCl晶体),同时检测出Pb盐[Pb_(5)(PO_(4))_(3)Cl]和Cd盐(CdS)特征峰。FTIR图谱的3510 cm^(-1)附近强吸收带源于—OH伸缩振动,胁迫过程导致峰形杂乱、峰位偏移;2D-IR结果说明Pb/Cd优先与金盏菊原生质体—OH和C O结合。从XPS图谱可以看出,反应前后原生质体C,O元素结合能有异。C(1 s)结合能略有增加,说明C原子参与了配位反应;O(1 s)峰位有所偏转,暗示含O基团对Pb/Cd的结合包含多种途径。新出现的Pb(4 f)峰源于π电子-Pb的交互作用;胁迫浓度增加导致Cd(3 d)结合能升高,表明Cd具有明显失电子倾向。相关结果可以与前期获得的Pb/Cd/金盏菊细胞壁结合特性互为补充,对于完善同领域的深度和广度、构建植物修复理论和技术体系意义重大。

Research of Three-Dimensional Fluorescence Spectra of RE^(3+)(RE=Eu,Tb) and Na_2WO_4 Co-doped Silica Luminescence Materials

In the preparation of this precursor tetraethlortho silicate (TEOS), sodium tungstate, ethyl alcohol, HCl and RECl3(RE=Eu,Tb) were mixed and then heated at 800 ℃ for 2 h, leading to a luminescent compound. The structure of the materials was characterized by TG-DTA and IR analysis, and the results indicate that the materials were in SiO2 network structure. Three-dimensional fluorescence spectra was used to characterize the luminescent properties of the materials. The luminescence property of doped and un-doped Eu3+or Tb3+ and Na2WO4 in silica materials were prepared and measured. The results show that good energy transfer from WO2-4 to Eu3+ ion, sensitized the luminescence intensity of Eu3+ remarkably. Tb3+ ion incorporated silica materials expressed the inverse energy transition from Tb3+ to WO2-4, however, we got the materials with homogeneous green blue fluorescent light. Finally, the energy transfer of WO2-4 and Eu3+, WO2-4 and Tb3+ were explained by energy levels diagram.

Complex Impedance Spectra Analysis of SnO_2-glaze Composites

SnO2-glaze composites were prepared by Sb-doped SnO2 and SiO2-CaO-Al2O3-B2O3 glaze. The composites changed from an electrical insulator to a conductor as the SnO2 content increased from Owt% to 90 wt% . The complex impedance spectra of the fabricated composites were investigated in the frequency range of 100Hz-40 MHz and three kinds of typical shape of complex impedance spectra were recorded and analyzed. The ,spectrum is quite close to the model of conduction via nonohmic contactiug when the SnO2 content is relatively low, In high loading region, the spectrum shows the conduction pattern through ohmic contact chains . In the moderate loading region, the model is a mixture of the above two models. Equivalent circuit of the composite changes from resistor-capacitor circuit to resistor-inductor circuit as the content of SnO2 increases.

Stabilities and Electronic Spectra for C_(78)O_2 Isomers

Structures and stabilities of 22 possible isomers for C78O2 based on C78（C2v） were studied by INDO series of methods. The most stable geometry is that two oxygen atoms are added to 1,2-bond crossed by the shortest z axis and 32,35-bond near the longest x axis in C78（C2v）,in agreement with the experiment of adducts for C78（C2v）. 1,2,32,35-C78O2 is more stable than 1,2,19,22-C78O2 by 0.12 kcal/mol and epoxide structures are formed in each isomer. Electronic spectra for C78O2 were investigated with INDO/CIS method. The reason of the blue-shift for UV absorptions of 1,2,32,35-C78O2 compared with that of C78（C2v） was discussed and electronic transition was theoretically assigned.

IR and Raman Spectra Properties of Bi₂O₃-ZnO-B₂O₃-BaO Quaternary Glass System

Among new low-melting-point glasses, bismuth ate glass is deemed to have the most potential as an environmentally friendly replacement for polluting Pb-containing glasses. Current studies of boro-bismuthate glasses focus on the structural influence of the additional oxide in the context of low-melting-point electronic sealing applications. In this study, the structure of quaternary Bi2O3- ZnO-B2O3-BaO glasses was investigated spectroscopic ally, with Fourier-transform-infrared (FT-IR) and Raman spectra recorded for glasses with different main oxide contents. Signals in the FT-IR are mainly observed around 500 cm﹣1, 720 cm﹣1, 840 cm﹣1, 980 - 1080 cm﹣1, and 1200 - 1500 cm﹣1, while the Raman scattering peaks are located at 130 cm﹣1, 390 cm﹣1, 575 cm﹣1, 920 cm﹣1, and 1250 cm﹣1. The glasses are mainly structured around [BO3] units and the numbers of [BiO6] and [BiO3] units increase with the Bi2O3 content increasing. Concurrently, the FT-IR absorption peaks associated with [BO4] units shift to lower wave numbers, indicating a loosening of the glass structure. However, as the B2O3 content is increased, the numbers of [BO3] and [BO4] units increase, while those of [BiO3] and [BiO6] units decrease, highlighting a densification of the glass structure. ZnO acts as a network modifier in these glasses.

Microscopic sdgIBM-2 description of low-lying excitation spectra of ^(48,52,56)Cr

Starting from the shell model configurations,valence nucleon effctive interactions and fermion E2 transition operator,a microscopic approach of sdgIBM-2 is used to calculate the energy spectra,E2 transitions,and binding energies for 48,52,56Cr.The results fit the experimental data quite well.

IR Spectra Analysis of SiO_2-TiO_2-GeO_2 Gel Glass of CO_2 Laser Transmitting Hollow Waveguide

Both titanium and germanium were introduced into silicon dioxide system by sol-gel method to move its region of anomalous dispersion caused by IR resonance absorption towards the wavelength of CO 2 laser.It is indicated by IR absorption spectra that as the content of SiO 2 decreases in this glass system TiO 2 and GeO 2 tends to exist in their own phases.As for the gel glass with a composition of 40SiO 2·30TiO 2·30GeO 2,when the temperature is below 600℃,germanium atoms exist mainly in Ge-O-Ge bonds.With the temperature increasing from 800℃ to 1000℃, titanium atoms in Si-O-Ti bonds almost transform into Ti-O-Ti bonds.Furthermore,a large number of Si-O-Ti and Si-O-Ge bonds formed when the temperature approaches 800℃,which makes a notable IR absorption band round the wavelength of CO 2 laser.Therefore, sol-gel based SiO 2-TiO 2-GeO 2 gel glass is a candidate material for CO 2 laser hollow waveguide.

Theoretical Study on the Structure and Vibrational Spectra for 4-methyl-3-penten-2-one

Density functional theory BLYP (using Becke's and Lee-Yang-Parr's correlation functionals), nb initio Hartree-Fock (HF) and hybrid DFT/HF B3LYP calculations were carried out to study the structure and vibrational spectra of 4-methyl-3-penten-2-one. The BLYP/6-31G* and scaled HF/6-31G* frequencies correspond well with each other and with available experimental assignment of the functional vibrational modes.

Studies on the Electronic Structures and Spectra of C_(78)(CH_2)_3

The structures and spectra of 20 possible isomers of C78（CH2）3 have been studied by using AMI, INDO/CIS and DFT methods. The results show that the most stable isomer is 1,2,3,4,5,6-C78（CH2）3 （A） with annulene structures, where three -CH2 groups are added to the 6/6 bonds located at the same hexagon passed by the shortest axis of C78 （C2v）. Compared with that of C78 （C2v）, the first absorption in the electronic spectrum of C78（CH2）3 （A） iS blue-shifted because of its wider LUMO-HOMO energy gap. While the IR frequencies of the C-C bonds on the carbon cage are red-shifted owing to the formation of annulene structures and the extension of the conjugated system. The chemical shifts of the carbon atoms in 13C NMR spectra are moved upfield upon the addition.

The Evolution of IR Spectra of H_2 Adsorbed on ZrO_2 with Changing Temperature（298－723K）

I.r.bands at 1559.0, 1441 .0, 1378 .9, 13603, 1031. 1,981 .4 and 947.3 cm -1 due tovarious types of dissociative adsorption of H2 over ZrO2 with changing temperatore wereobserved by in situ FT-IR spectroscopy.

Spectra properties of Yb^(3+),Er^(3+):Sc_2SiO_5 crystal

The influence of Er3+ ions on the spectra of Yb^(3+),Er^(3+): Sc_2 SiO_5(SSO) single crystal, which was obtained by Czochralski(Cz) method, is discussed. The absorption coefficient at 980 nm was 13.36 cm^(-1) with a peak absorption cross-section of 1.46 × 10^(-20) cm2. The emission cross-sections at 1034 nm and 1062 nm were 5.5 × 10^(-21) cm^2 and4.9 × 10^(-21) cm^2, respectively. The fluorescence lifetime was estimated as 1.24 ms at 1061 nm. The mechanical properties of SSO single crystal were also presented.

Different Behaviors of ACE Inhibitor Tripeptide Ile-Ile-Pro in Aqueous and DMSO Solutions by All-Atom MD Simulations and 2D-NOESY Spectra

All-atom molecular dynamic simulations and 2D-NOESY spectra were used to study the conformations and hydrogen bonds of ACE inhibitory tripeptide Ile-Ile-Pro(IIP) in aqueous and DMSO solutions. RMSD, Dis, Rg and SASA were adopted to characterize the properties of tripeptide Ile-Ile-Pro in the MD simulations. Interestingly, the tripeptide molecule IIP exhibited different behaviors in aqueous and DMSO solutions. In aqueous solution, IIP was very flexible. The conformation could shift between extended and folded states very quickly. However,in DMSO solution, more folded conformations were observed. The interesting phenomena were proved by 2D-NOESY spectra.

Atmospheric CO_2 retrieval with a look-up-table based method by combining near and thermal infrared spectra

In order to precisely retrieve the atmospheric CO2 , a retrieval method based on both near infrared （NIR） and thermal infrared （TIR） is established firstly. Then a look-up-table （LUT） based fast line-by-line radiative transfer model （RTM） was integrated into the retrieval procedure to accelerate radiative transfer calculations. The LUT stores gas absorption cross-sections as a function of temperature, pressure and wavenumber. It could greatly reduce calculating time in radiative transfer compared to direct line-by-line method. Then retrieval was simulated using NIR, TIR and both bands. The retrieved CO2 profiles suggest joint approach could reconstruct CO2 profile better than those using NIR or TIR alone. Joint retrieval using both bands simultaneously could provide better constrain to CO2 vertical distribution in the whole troposphere.

Spectra2使用介绍

介绍了Spectra2测试仪的基本功能,并用SIP协议自环测试的例子简要说明其使用方法。

SYNTHESES AND SPECTRA OF HETEROPOLY BLUES OF DOUBLE 2:17 MOLYBDOPHOSPHATES LANTHANIDE COMPLEXES

The present paper reports eight heteropoty blues of double 2:17 motybdophosphates tanthanide comptexes with tacunary Dawson structure, i.e., K_(17)H_2[Ln(P_2Mo_2~ⅤMo_(15)~ⅥO_(16))_2], nH_2O and K_(17)H_4 [Ln(P_2Mo~Ⅴ_4Mo_(13)~ⅥO_(61))_2], nH_2O(Ln=La, Pr, Sm, Yb). They were characterized by etementat anatyses, potentiometric titration, IR, UV, potarography, cyclic vottammetry, X-ray photoelectron spectra, X-ray powder diffraction, thermat analyses and ESR. The results show that the properties of these heteropoty btues are different from those of heteropoty blues with saturated Dawson structure and other tacunary series. They are more stabte than their parent heteropoty acids in aqueous sotution and have the abitity of anti-base decomposition.

Preparation of I_2 Clusters and Their Absorption Spectra

Samples have been prepared at different temperatures by loading I2 molecules into the cages of zeolite 5A, and the measurements of the absorption spectra have been carried out for the prepared samples. It is shown that I2 molecular clusters are formed in the cages of zeolite 5A,and it is also found that moIecuIar clusters which are bonded with intermoIecuIar forces have an important feature, namely, the intermolecular distance in molecular clusters can be changed on different preparing conditions and the blue shift of absorption edges can not be as the criterion of forming molecular clusters.

Study on lattice vibrational properties and Raman spectra of Bi_2Te_3 based on density-functional perturbation theory

We present a variational density-functional perturbation theory （DFPT） to investigate the lattice dynamics and vibra- tional properties of single crystal bismuth telluride material. The phonon dispersion curves and phonon density of states （DOS） of the material were obtained. The phonon dispersions are divided into two fields by a phonon gap. In the lower field, atomic vibrations of both Bi and Te contribute to the DOS. In the higher field, most contributions come from Te atoms. The calculated Born effective charges and dielectric constants reveal a great anisotropy in the crystal. The largest Born effective charge generates a significant dynamic charge transferring along the c axis. By DFPT calculation, the greatest LO-TO splitting takes place in the infrared phonon modes and reaches 1.7 THz in the Brillouin zone center. The Raman spectra and peaks corresponding to respective atomic vibration modes were found to be in good agreement with the experimental data.