Raman and infrared spectroscopic investigation of some hydrous LnTPPTS complexes (Ln=La,Sm)

The Raman and IR spectra of LnTPPTS·10H₂O [Ln=La,Sm, TPPTS=P(m-C₆H₄SO₃) ₃ ³⁻ ] complexes are reported. Based on the observed Raman and IR characteristic frequencies, a vibrational assignments has been made for these complexes. Coordination induces a lengthening of the S−O bonds and a shortening of the C−S bond. The C−S stretching frequencies should therefore increase while the position of the should move to a lower wavenumber. Vibrational modes of metal-oxygen polyhedron V _(La-O) at 146, 168,253 cm⁻¹ are the structural charactrization for coordinate bond of LnTPPTS complexes. Chen Zhenhua: Born in 1938, Professor     

Structural OH in mantle-derived clinopyroxene megacrysts from Nushan

Thirteen clinopyroxene megacrysts from Nushan Cenozoic basalts have been investigated by Fourier transform infrared spectrometer(FTIR). The results demonstrate that all samples contain trace amount of structural OH. Clinopyroxenes from Nushan show four groups of absorption bands, in which, 3 472–3 506 cm⁻¹ is the major characteristic one. It is suggested that the position of major band is probably related to AI content: the position of major characteristic band for high-AI samples is around 3 470 cm⁻¹, whereas that for low-AI samples around 3 620 cm⁻¹.     

Raman spectroscopy of single quantum well wires

We used the micro-Raman spectroscopy to investigate the V-grooved quantum well wires (QWWs), and first observed and assigned the Raman spectra of single QWW. They were the disorder induced modes at 223 and 243 cm⁻¹, confined LO mode of GaAs QWW at 267 cm⁻¹, and higher order peaks of disorder induced modes at 488 and 707 cm⁻¹.     

Hydroxyl in continental deep subduction zone: Evidence from UHP eclogites of the Dabie Mountains

Infrared spectra in the region of 3 000 to 4 000 cm⁻¹ have been measured by an FTIR spectrometer on minerals in UHP eclogites from the Bixiling and Shuanghe areas, the Dabie Mountains. It is shown that omphacite is the most important hydrous mineral (100–200 μg/g) in UHP eclogites. Garnet and quartz contain virtually no H₂O or OH. Accessory mineral rutile contains a significant amount of OH (>1 000 μg/g). Coesite gives no indication of the presence of OH but apparent H₂O bands. The results have considerable implications for existing forms and contents of hydroxyl in the continental deep subduction zone, the eastern Dabie Mountains.     

Temperature dependence of surface enhanced Raman scattering on C<Subscript>70</Subscript>

The temperature dependence of surface enhanced Raman scattering of the C70 molecule is reported. The Raman scattering of C70 molecules adsorbed on the surface of a silver mirror was measured at different temperatures. The experimental results indicate that the relative intensities of the Raman features vary with the temperature of the sample. When the temperature decreases from room temperature to 0℃, the relative intensifies of certain Raman bands decrease abruptly. If we like the strongest band 1565cm^-1 as a standard value 100, the greatest decrease approaches to 43%. However, with the further decrease in the temperature these relative intensities increase and resume the value at room temperature. And such a temperature dependence is reversible. Our results show that the adsorption state of the C70 molecules on the silver surface around 0℃ changes greatly with the temperature, resulting in a decrease in relative intensities for some main Raman features of C70 molecule. When the temperature is lower than 0℃, the adsorption state changes continually and more slowly. Synchronously, eight new Raman features, which have not ever been reported in fiterature, are observed in our experiment and this enriches the basic information of the vibrational modes for C70 molecule.     

Investigation of the interfacial water structure on poly[2-（dimethylamino）ethyl methacrylate] at the air/water interface by sum frequency generation vibrational spectroscopy

The effect of pH on the conformation of surface alkyl groups and the structure of interfacial water molecules on poly[2-(dime-thylamino)ethyl methacrylate](PDEM) at the air/water interface were investigated with sum frequency generation vibrational spectroscopy(SFG-VS).At pH 4.1,the hydrogen bonding SFG spectra were similar to that of the air/pure water interface.As the pH increased from 5.4 to 9.6,the SFG intensities of both highly ordered hydrogen bonding(3200 cm-1 band) and less-ordered hydrogen bonding(3400 cm-1 band) were enhanced because of the charge-induced effect of deprotonated PDEM.The free OH peak disappeared completely because it was replaced by interfacial PDEM molecules.At pH 11.5,a new spectral band appeared at about 3580 cm-1 in the ppp and sps spectra,and this could be assigned to the C2v asymmetric stretching mode of the water molecules through molecular symmetry simulation.These hydrogen bonding structures are fully consistent with the conformational change of PDEM alkyl groups,and PDEM molecules act as a Hofmeister solvent.PDEM molecules are kosmotropic when they are charged and become more chaotropic as the pH increases.     

Statistical properties for the vibrational energy levels of OCS

A potential energy surface for the electronic ground state of carbonyl sulfide was optimized by using a self-consistent configuration-interaction method and involving the recently observed vibrational band origins up to 8000 cm⁻¹. With the optimized potential, the vibrational energy levels of OCS up to 15000 cm⁻¹ were computed using the discrete variable representation method and Lanczos algorithm. Approximately 480 vibrational energy levels were identified. The statistical investigation showed that the vibrational energy levels of OCS up to 15000 cm⁻¹ are largely regular.     

Resonance-enhanced multiphoton ionization spectroscopy on the B′2Σ+ and B2Π states of NS

Resonance-enhanced multiphoton ionization （REMPI） spectra of N^32S and N^34S have been recorded in the range of 35700-40200 cm^-1. The radical was generated by a pulsed dc discharge of a mixture of SF6 and N2 under a supersonic free jet condition. All the 16 observed bands of N^32S radicals have been assigned, among which 12 bands belong to three transition progressions （v′=0-4, 0）, （v′=1-4, 1） and （v′=2-4, 2） from the X^2П ground state to the B′^2∑^＋ upper state and the rest correspond to （9, 0）, （10, 0）, （11, 0） and （12, 0） bands of B^2П-X^2П transition, respectively. Analysis of the rotationally resolved spectra yields exhaustive spectroscopic constants of both the X^2П ground state and the B′^2∑^＋ excited state. The electronic transition bands of the isotopic molecule N^34S have been rotationally analyzed for the first time and the rotational constants of the ground and upper states have been determined simultaneously.     

One-step and high-density protein immobilization on epoxysilane-modified silica nanoparticles

Silica nanoparticles are most commonly modified with amino-silanes, followed by post-modification activation for protein immobilization. In this work, epoxy-functionalized silica nanoparticles were prepared by modification with glycidyloxypropyl trimethoxysilane （GPTMS） for direct protein immobilization. Silica nanoparticles possessed an average size of 46 nm, but increased to 63 nm after GPTMS modification. Reaction time, reaction temperature and GPTMS content had no significant effect on par- ticle size. Zeta potential of SiO2 changed from -26mV to ＋38mV after modification. Fourier-transformed infrared spectroscopy revealed alkyl C--H bending and stretching bands at 2944 cm-1, 1343 cm-1 and 1465 cm-1, respectively, for the modified nanoparticles. Fluorescein cadaverine was found to bind to GPTMS-modified SiO2, but not to bare SiO2, indicating the chemical reactivity of epoxy groups on the modified nanoparticle with amines. Finally, fluorescenUy labeled bovine serum albumin （BSA） was used as a model protein to investigate the capacity of epoxy-SiO2 nanoparticles for protein immobilization. The results showed that more proteins were immobilized on the particle with longer reaction time, higher NaCI concentration, lower pH, and less GPTMS content. More importantly, proteins bound to epoxy-SiO2 nanoparticle were highly stable. Under optimized reaction conditions, as much as 25 mg BSA/g nanoparticle was covalentiy attached to the nanoparticle. The epoxy silane modification of silica nanoparticles offers a reactive surface for one-step and high-density protein immobilization.     

Synthesis and structure determination of ruthenium and osmium complexes with 2,6-bis-(diphenylphosphinomethyl) pyridine

2,6-Bis (diphenylphosphinomethyl) pyridine (PNP) reaction with Na₂OsCl₆ · 6H₂O to give the five coordinated, sixteen-electron complex Os (PNP)Cl₂. In the presence of formaldehyde, the reaction between Na₂OsCl₆· 6H₂O and PNP proceeds rapidly in boiling ethanol to give the coordinately saturated Os(PNP)Cl₂(CO). The IR spectrum of Os(PNP)Cl₂(CO) shows a strong absorption band at 1 970 cm⁻¹ assignable tov _∞ stretch. PNP reacts with RuCl₂(PPh₃)₃ and RuCl₂(DMSO)₄ (DMSO=dimethyl sulfoxide) to give Ru(PNP)Cl₂ (PPh₃) and Ru(PNP)Cl₂ (DMSO) respectively. The average Ru−Cl, Ru−P and Ru−N bond distance in Ru(PNP)Cl₂(PPh₃) determineby X-ray crystallography are 0.242, 0.236 and 0.216 nm, respectively. Li Zhaoying: born in July 1949, associate professor     

NO adsorption study on the distribution of Ni2 + ions on the various micro-environments of carriers

The decrease of the electron density in the d orbits of Ni2+ ions, resulting from the disturbance of micro-environments in which Ni2+ ions are located, makes the frequency of adsorbed NO shift higher. The shift degree is determined mainly by the property of the microenvi-ronments. When Ni2+ ions are located on SII , SII · (SI ·) sites of Y zeolite or on the surface of γ-alumina, their NO adsorption gives rise to IR bands at 1 905, 1 900 and 1 855-1 875 cm-1, respectively. The distribution of Ni2 + ions on the various micro-environments of USY zeolite, AI2O3 and MS mixed carrier has also been discussed according to the different frequencies of adsorbed NO, as well as the influence of NiO loading.     

β-Ga2O3的高压原位拉曼光谱

利用金刚石对顶砧（DAC）高压装置产生高压, 在0~23.4 GPa研究β相氧化镓（β-Ga₂O₃）晶体高压原位拉曼光谱. 根据高压拉曼光谱的实验数据, 给出了β-Ga₂O₃晶体拉曼振动频率与压力的关系, 并将外振动谱线144 cm^-1归属于平移模, 169 cm^-1归属于转动模. 在18 GPa附近, 发现两个新的拉曼峰232 cm^-1和483 cm^-1, 由这两个峰的强度随压力的升高逐渐增强可知, β-Ga₂O₃晶体发生了压力导致的结构相变.      

Experimental studies on silicate structures of basaltic glasses quenched at 1 65093 and 1–3.5 GPa

A series of melting experiments was carried cut at 1 650°C and 1.00–3.00 GPa using alkaline basalt as starting material. The cornpitions of quenched basaltic glasses in the products were detected by electron micro probe. Their CIPW norms were calculated and their refractive indices were determined by the oil-infused method. The Raman spectrum of the quenched basaltic glasses indicates that their main structural species are monomer [Si₂O₄]1⁴⁻, chain [Si₂O₆]1^4- and sheet [Si₂O₅]1^2-. The relationship at the same temperature between the proportions of integrated areas of structural species, and compositions and pressures was discussed.     

Kinetics of chemical leaching of chalcopyrite from low grade copper ore: behavior of different size fractions

The kinetics of the chemical leaching of copper from low grade ore in ferric sulfate media was investigated using the constrained least square optimization technique. The experiments were carried out for different particle sizes in both the reactor and column at constant oxidation-reduction potential (E_h), pH values, and temperature. The main copper mineral was chalcopyrite. About 40% of Cu recovery is obtained after 7 d of reactor leaching at 85℃ using -0.5 mm size fraction, while the same recovery is obtained at 75℃ after 24 d. Also, about 23% of Cu recovery is obtained after 60 d of column leaching for +4–-8 mm size fraction whereas the Cu recovery is as low as about 15% for +8–-12.7 and +12.7–-25 mm size fractions. A 4-stage model for chalcopyrite dissolution was used to explain the observed dissolution behaviors. The results show that thick over-layers of sulphur components cause the parabolic behavior of chalcopyrite dissolution and the precipitation of Fe3+ plays the main role in chalcopyrite passivation. In the case of coarse particles, transformation from one stage to another takes a longer time, thus only two stages including the initial reaction on fresh surfaces and S0 deposition are observed.     

Graded bandgap semiconductor thin film photoelectrodes

A graded bandgap oxide semiconductor thin film electrode was designed in order to obtain a photoelec-trochemically stable photoelectrode, with wide absorption range. The graded bandgap Ti_1−x V _x O₂ film electrode was prepared by heating the stacked layers of V/Ti in varying ratios, which were coated on the substrate by the sol-gel method using the starting solution with various V/Ti ratios. XPS result showed that the composition gradient was achieved for the film. The Ti_1−x V _x O₂ film electrode was found to be photoelectrochemically stable. Its photovoltage was about 360 mV. Obvious visible light photoresponse was observed for the Ti_1−x V _x O₂ film electrode. Compared with the pure TiO₂ electrode, the photocurrent onset potential of the Ti_1−x V _x O₂ film electrode was shifted positively, probably because the accumulation of vanadium at the electrode surface causes the recombination of the electrons and holes, and the lowest level of the conduction band of Ti_1−x V _x O₂ is lower than that of TiO₂. Impedance analysis showed that the donor density of the Ti_1−x V₂O₂ film electrode was higher than that of TiO₂ film electrode.     

Preparation,crystal structure and quantum chemical investigation of [Li(NTO) (H2O)]

[Li(NTO)(H₂O)₂] was prepared by mixing the aqueous solution of 3-nitro-1,2,4-triazol-5-one (NTO) and lithium hydroxide. The crystal structure of [Li(NTO)(H₂O)₂] was determined by single crystal diffraction analysis. The crystal is monoclinic, space group P2₁/n with crystal parameters of a = 0.742 0(2) nm, b = 0.344 9(1) nm,c = 2.490 6(3) nm, β= 94.89(1)°, Z = 4,D _c , = 1.799 g cm⁻³,V = 0.635 nm³, μ = 1.591 cm⁻¹, F(000) = 392. The finalR is 0.051. The MNDO MO calculation shows that the coordinate bonds of title compound possess certain extent of covalent character. O₂ atom of NTO anion is bonded to Li atom; the nitro group will be lost first when NTO is decomposed.     

Preparation by a rheological phase reaction method and thermal decomposition reaction mechanism of nickelous salicylate tetrahydrate

0　IntroductionInrecentyears,studiesonBinghamfluid ,suchasElec trorheologicalfluid ,areactivelypursued[1 6] .Rheologicaltechniqueshavebeenplayinganimportantroleinsyntheticchem istry .Therheologicalphasereactionmethodisthe processofpreparingcompoundsormaterialsfromasolid liquidrheologicalmixture.Thatis,thesolidreactantsarefullymixedinapropermolarratio ,andmadeupbyaproperamountofwaterorothersolventstoaBinghambodyinwhichthesolidparticlesandliquidsubstanceareuniformlydistributed ,sothattheprodu…     

Laser cooling using anti-stokes fluorescence in Yb3+-doped fluorozirconate glasses

The fluorozirconate glasses ZBLANP (ZrF₄−BaF₂−LaF₃−NaF−PbF₂) doped with different Yb³⁺ concentration were prepared. The Raman spectra and absorption spectra are measured to substantiate the existence of phonon-assisted emission. After analyzing the normalized absorption spectra of samples with different Yb³⁺-doped concentration, we calculated the maximum cooling effect in the 3 wt% Yb³⁺-doped sample pumped at 1 012.5 nm. The corresponding cooling capability is about −4.09 °C/W and the cooling efficiency reaches 1.76%. Foundation item: Supported by the Key Science Foundation of Wuhan (9601P0223) Biography: Xu Tian-ming (1978-), female, Master candidate, research direction: information optics and nonlinear optics.     

CO2的温室效应饱和度分析及其大气体积分数预测模型

通过精确的LBLRTM逐线积分模式建立CO_2体积分数变化模型,分析了CO_2的温室效应饱和度,并对未来地表温升的变化趋势进行了预测.结果表明,目前CO_2的持续排放只能使其在680cm~(-1)强吸收带中心达到饱和,而在未来相当长一段时间内,其仍将通过该吸收带的翼区以及1 000cm~(-1),1 350cm~(-1)与1 900cm~(-1)等弱吸收带对地表红外辐射表现出强烈的吸收,CO_2的温室效应还远未达到饱和;如果按照当前CO_22.2(mL/·m~(-3))/a的年排放速率,CO_2的大气体积分数将会持续增加,从而造成地表温度不断升高,到2056年,地表温升将会达到2K.     

Remote sensing of algal blooms using a turbidity-free function for near-infrared and red signals

HARMFUL ALGAL BLOOM ACTS UPON IMPORTANT ENVIRON-MENTAL PROBLEMS IN COASTAL WATERS.A UNIFIED AND IM-PLEMENTING METHOD FOR SURVEY AND MONITORING ALGALBLOOMS HAS BEEN DEVELOPED SINCE LAST DECADE.HOWEVER THERE IS A DATA GAP OF ABOUT TENS YEARS IN THE PERIOD W…