NO分子通过中间共振态C^2Σ态的共振增强多光子离化光谱(英文)

利用激光光谱技术得到NO分子经由电子态C2 Σ←X2 Π跃迁的多光子共振离化光谱 .NO分子通过中间共振电子态C2 Σ ,实现了五光子共振离化过程 .根据实验计算得到了NO分子C2 Σ态平衡位置的力常数k =(2 .4 4± 0 .0 8)× 10 3N·m- 1.

大气中NO气体的2种激光光谱探测方法

介绍利用激光光谱探测NO气体的2种方法———激光辐照荧光光谱法与共振增强多光子离化光谱法,同时介绍了利用NO的上述2种光谱学技术间接探测NO2、DNT等氮氧化物的原理。

光谱学与光谱技术

O433.5 2000031585碘分子高激发态光学双共振多光子离化光谱=Doubleresonance multiphoton spectrum of high excitedstate of iodine[刊,中]/张连水,刘宁宁,李晓苇,傅广生（河北大学物理系.河北,保定（071002））,陈艳梅（保定师范专科学校物理系.河北,保定（071000））//光谱学与光谱分析.—1999,19（4）.—525-528利用双色共振多光子离化技术（00DR-MPI）,对I2分子离子对态FOu+态进行了较为仔细的研究。利用已知的分子常数,对所得谱线进行了标识和归属。

Influence of thermal history on conversion of aluminate species in sodium aluminate solution

It is necessary to clarify the influence of thermal history on the conversion of aluminate species in sodium aluminate solution in order to optimize Bayer alumina production. The interconversion of various solution species in the systems was investigated by measuring the infrared spectra of sodium aluminate solution with different compositions after separate heat treatment, dilution and concentration. The results show that increasing temperature or prolonging holding time favors the transformation of Al2O（OH）2- to Al—OH vibration（condensed Al O4 tetrahedral aluminate ion） at about 880 cm-1 and Al（OH）-4. A12O（OH）2-66 and Al—OH tetrahedral dimer ions convert rapidly to Al（OH）-4 during the dilution process; however, the back transformation of Al（OH）-4 to the Al—OH tetrahedral dimer ions can occur in diluted sodium aluminate solution. As for the concentration process, the transformation of Al（OH）-4 to A12O（OH）2-6 and Al—OH tetrahedral dimer ions can take place, while it is relatively difficult to transform to A12O（OH）2-6.

Purification and Characterization of Flammulin,a Basic Protein with Anti-tumor Activities from Flammulina velutipes

Aim To purify and characterize flammulin, a basic protein with anti-tumoractivities. Methods Ammonium sulfate, ethanol fractionation and column chromatography were used forseparation and purification. Electrophoretic analysis, amino acid analysis, and MS of flammulin werecarried out. Results Flammulin was purified to electrophoretic homogeneity and crystallized. With amolecular mass of 19891.13 Da, pI 8.9, λ_(max) = 276 - 278 nm, λ_(min) = 250 nm, flammulin wascharacterized by its lack of methionine. Fingerprint mapping of flammulin was determined by MALDI-MSfollowing in-gel protease digestion; no close matches were identified. Conclusion Flammulin waspurified to electrophoretic homogeneity, and its characteristics are discussed for the first time.

Analysis of variabilities of serum proteomic spectra in patients with gastric cancer before and after operation

AIM： To study the variabilities of serum proteomic spectra in patients with gastric cancer before and after operation in order to detect the specific protein markers that can be used for quick diagnosis of gastric cancer. METHODS： Proteomic spectra of 46 serum samples from patients with gastric cancer before and after operation and 40 from normal individuals were generated by IMAC-Cu protein chip and surface-enhanced laser desorption/ionization time of flight mass spectrometry. RESULTS： Fourteen differentially expressed proteins in serum were screened by analysis of proteomic spectra of preoperative patients and normal individuals. We obtained 4 proteins （heat shock protein 27, glucoseregulated protein, prohibitin, protein disulfide isomerase A3） making up marker pattern which was able to class the patient-team and normal-team. These marker patterns yielded 95.7% sensitivity and 92.5% specificity, respectively. The proteins over-expressed in serum of preoperative patients were obviously down-regulated. CONCLUSION： Specific protein markers of gastric cancer can be used for the quick diagnosis of gastric cancer and judgment of prognosis. SELDI-TOF-MS is a useful tool for the detection and identification of new protein markers in serum.

Structural and Infrared Spectroscopic Study on Solvation of Acetylene by Protonated Water Molecules

The effect of solvation on the conformation of acetylene has been studied by adding one water molecule at a time. Quantum chemical calculations of the n＋ （C2H2）（H2O）n （n=1-5） clusters indicate that the H2O molecules prefer to form the OH...Tr interaction rather than the CH...O interaction. This solvation motif is different from that of neutral （C2H2）（H2O）n （n=1-4） clusters, in which the H2O molecules prefer to form the CH...O and OH...C Hbonds. For the H＋（C2H2）（H2O）n cationic clusters, the first solvation shell consists of one ring structure with two OH...Tr H-bonds and three water molecules, which is completed at n=4. Simulated infrared spectra reveal that vibrational frequencies of OH... H-bonded O-H stretching afford a sensitive probe for exploring the solvation of acetylene by protonated water molecules. Infrared spectra of the H＋ （C2H2）（H2O）n （n=1-5） clusters could be readily measured by the infrared photodissociation technique and thus provide useful information for the understanding of solvation processes.

Determination of trace multi-elements in coal fly ash by inductively coupled plasma mass spectrometry

The contents of Cr, Cu, Ni, As, Cd and Pb in coal fly ash were determined by a high resolution inductively coupled plasma mass spectrometry method. The sample digestions were performed in closed microwave vessels with HNO3, HClO4 and FIE The optimum conditions for the determination were obtained. The applicability of the proposed method was validated by the analysis of coal fly ash reference material （NIST SRM 1633a）. The results show that most of the spectral interferences can be avoided by measuring in the high resolution mode （maximum mass resolution R=9 000）. The detection limit is from 0.05 to 0.21 μg/g, and the precision is fine with relative standard deviation less than 4.3%.

Multisymplectic Pseudospectral Discretizations for(3+1)-Dimensional Klein-Gordon Equation

We explore the multisymplectic Fourier pseudospectral discretizations for the (3+1)-dimensional Klein-Gordon equation in this paper.The corresponding multisymplectic conservation laws are derived.Two kinds of explicitsymplectic integrators in time are also presented.

Germanium separation and purification by leaching and precipitation

In this research work, extraction and purification of germanium from zinc leach residues(ZLR) were investigated. The results of ICP, XRF, and atomic adsorption spectroscopy(AAS) tests show that contents of germanium, iron, lead, and zinc within the leaching residue were 105×10^(-6), 3.53%, 10.35%, and 8.8%, respectively. XRD results indicate that the main minerals were in different forms of sulfates(CaSO_4·2H_2O, PbSO_4 and ZnSO_4·6H__2O), silicate(SiO_2), and oxide(Fe_2O_3). Dissolution of leaching filter cake was carried out using 5 parameters and each in 4 levels(acid concentration, temperature, time, liquid-to-solid ratio, and stirring speed) by Taguchi method(L_(16)), and then optimization of the effective parameters by response surface method. Under optimum conditions, zinc and germanium dissolution efficiencies were 88.71% and 8%, respectively. Leaching tests with sulfuric acid(added di-ammonium oxalate monohydrate) and hydrochloric acid(HCl) on the residues obtained from previous-stage sulfuric acid dissolution, yielded germanium and iron recoveries of 83%, 88%, 40%, and 90%, respectively. Thus, leaching experiment with sulfuric acid(added di-ammonium oxalate monohydrate) was superior to that with hydrochloric acid due to high and low extraction amounts of germanium and iron, respectively. Precipitation experiments revealed that germanium purification with tannic acid presented a better result compared to sodium hydroxide and ammonia. Under optimum conditions, contents of germanium and iron in the solution after precipitation were 0.1505% and 14.7% with precipitation yields of 91% and 52%, respectively.

Infrared Spectroscopy of CO2 Transformation by Group Ⅲ Metal Monoxide Cations

Infrared photodissociation spectroscopy of mass-selected[MO(CO2)n]^+(M=Sc,Y,La)complexes indicates that the conversion from the solvated structure into carbonate one can be achieved by the ScO^+ cation at n=5 and by the YO^+ cation at n=4,while only the solvated structures are observed for the LaO^+ cation.These findings suggest that both the ScO^+ and YO^+cations are able to fix CO2 into carbonate.Quantum chemical calculations are performed on[MO(CO2)n]^+ to identify the structures of the low-lying isomers and to assign the observed spectral features.Theoretical analyses show that the[YO(CO2)n]^+ complex has the smallest barrier for the conversion from the solvated structure into carbonate one,while[LaO(CO2)n]^+ exhibits the largest conversion barrier among the three metal oxide cations.The present system affords a model in clarifying the effect of different metals in catalytic CO2 transformation at the molecular level.

Inorganic Elemental Determinations of Marine Traditional Chinese Medicine Meretricis concha from Jiaozhou Bay:The construction of Inorganic Elemental Fingerprint Based on Chemometric Analysis

The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese medicine （TCM） for the treatment of asthma and scald bums. For that, the inorganic elemental contents ofMeretricis concha from five sampling points in Jiaozhou Bay have been determined by means of inductively coupled plasma optical emission spectrometry, and the comparative investigations based on the contents of 14 inorganic elements （A1, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se and Zn） of the samples from Jiaozhou Bay and the previous reported Rushan Bay were performed. It has been found that the samples from the two bays are ap- proximately classified into two kinds using hierarchical cluster analysis, and a four-factor model based on principle component analysis could explain approximately 75% of the detection data, also linear discriminant analysis can be used to develop a prediction model to distinguish the samples from Jiaozhou Bay and Rushan Bay with accuracy of about 93%. The results of the present investi- gation suggested that the inorganic elemental fingerprint based on the combination of the measured elemental content and chemom- etric analysis is a promising approach for verifying the geographical origin ofMeretricis concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM.

Studies on the Authenticity of Local Wines by Spectroscopic and Chemometric Analysis

The authenticity of 91 wines produced in Cyprus from both indigenous and other vine varieties were investigated by a holistic approach, using, advanced technology such as SNIF-NMR （site-specific natural isotopic fractionation-nuclear magnetic resonance） and 1R-MS （isotope ratio-mass spectrometry） for the determination of the stable isotopes and ICP （inductively coupled plasma spectroscopy） for some heavy metals. The spectroscopic characteristics were evaluated statistically using different chemometric methods. The dependency of the D/H （deuterium/hydrogen） ratio of the methylene site in the ethanol molecule （D/H）ll and also theδ ^18O values of the wine water, were the most useful discriminators. Isotopic results allow us to have a complete idea about the regional variability of the isotopes. Among the metals, Ni followed by Pb was the ones with the highest discrimination value. The determined concentrations of Pb, Ni, Cr and Cd that are related to the safety of wines were within the acceptable limits that have been established by the OIV （international organization of vine and wine） or comparable with the results of the wines of other European countries. The study of the correlation between the load of heavy metals and isotopes in wines showed a dependence on the grape variety but not the geographical location of the vineyard. This is probably due to the close proximity of wine regions in Cyprus.

Infrared Photodissociation Spectroscopic and Theoretical Study of [Co（CO2）n]+ Clusters

The mass-selected infrared photodissociation (IRPD) spectroscopy was utilized to investigate the interactions of cationic cobalt with carbon dioxide molecules. Quantum chemical calculations were performed on the [Co(CO2)n]^+ clusters to identify the structures of the low-lying isomers and to assign the observed spectral features. All the [Co(CO2)n]^+(n=2-6) clusters studied here show resonances near the CO2 asymmetric stretch of free CO2 molecule. Experimental and calculated results indicate that the CO2 molecules are weakly bound to the Co+ cations in an end-on con guration via a charge-quadrupole electrostatic interaction. The present IRPD spectra of [Co(CO2)n]^+ clusters have been compared to those of Ar-tagged species ([Co(CO2)n]^+-Ar), which would provide insights into the tagging effect of rare gas on the weakly-bounded clusters.

NO分子420～495nm波长范围的共振多光子离化谱

以皮秒Nd:YAG激光器泵浦光学参量发生/放大器(OPG/OPA)做激发源,得到了NO分子在420～495nm波长内的共振增强多光子离化(REMPI)谱,离化信号随激光强度的近4次方变化关系表明,NO分子通过吸收4个光子而离化,NO分子由基电子态X2∏(v"=0)经过中间共振态A2∑(v′=0.1)、F2Δ(v′=0,1,2)和H2∑(v′=0,1,2),通过(2+2)或(3+1)过程而离化。利用最小二乘法拟合获得了NO分子A2∑、F2Δ和H2∑态的振动常数及平衡位置的力常数,结果与文献报道基本符合。

Structural and Bonding Properties of Al_(n)C_(4)^(−/0)(n=2−4)Clusters:Anion Photoelectron Spectroscopy and Theoretical Calculations

We measured the photoelectron spectra of Al_(n)C_(4)^(−)(n=2−4)clusters by using size-selected anion photoelectron spectroscopy.The structures of Al_(n)C_(4)^(−/0)(n=2−4)clusters were explored with quantum chemistry calculations and were determined by comparing the theoretical results with the experimental spectra.It is found that the most stable structure of Al_(2)C_(4)^(−) anion is a C_(2v)symmetry planar structure with two Al atoms interacting with two C_(2)units.In addition,Al_(2)C_(4)^(−) anion also has a D∞h symmetry linear structure with two Al atoms located at the two ends of a C_(4)chain,which is slightly higher in energy than the planar structure.The most stable structure of neutral Al_(2)C_(4)has a D∞h symmetry linear structure.The most stable structure of Al_(3)C_(4)^(−) anion is a planar structure with three Al atoms interacting with two C_(2)units.Whereas neutral Al_(3)C_(4)cluster has a C_(2v)symmetric V-shaped bent structure.The global minima structures of both Al_(4)C_(4)^(−) and neutral Al_(4)C_(4)are C_(2)h symmetry planar structures with four Al atoms interacting with the ends of two C_(2)units.Adaptive natural density partitioning analyses of Al_(n)C_(4)^(−)(n=2−4)clusters show that the interactions between the Al atoms and C_(2)units have bothσandπcharacters.

Influence of Cu（II） on Ag（I） Recovery by Photocatalytic Reduction Method with TiO2 Suspension

Photocatalytic reduction method using TiO2 suspension for removal as well as possibly recovery of silver （Ag（I）） in the presence of Cu（II） is examined. The photocatalytic reduction was performed by batch technique in a closed reactor equipped with UV lamp. The concentration of unreduced Ag（I） was analyzed by atomic absorption spectrophotometry method. The research results indicate that Ag（I） in the solution can be removed and recovered effectively as silver metal Ag（0） deposited on the surface of TiO2 for photocatalytic reduction. In addition, the presence of Cu（II） ion with increasing concentration leads to a proportional decline in Ag（I） photoreduction due to the prominent competition in the adsorption on the surface of TiO2. The effectiveness of Ag（I） ion photoreduction in the presence of Cu（II） ion is strongly influenced by solution pH and the highest photoreduction is obtained at pH 5 - 8, which is related with the speciation ofAg（I）, TiO2 surface as well as Cu（II） in the solution.

High tap density of Ni_3(PO_4)_2 coated LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 with enhanced cycling performance at high cut-off voltage

The Li Ni1/3Co1/3Mn1/3O2 is first obtained by the controlled crystallization method and then coated with Ni3(PO4)2particles. The effects of the coating on rate capability and cycle life at high cut-off voltage are investigated by electrochemical impedance spectroscopy and galvanostatic measurements. The element ratio of Ni:Mn:Co is tested by inductively-coupled plasma spectrometer(ICP) analysis and it testified to be 1:1:1. It is indicated that Ni3(PO4)2-coated Li Ni1/3Co1/3Mn1/3O2 has an outstanding capacity retention, where 99% capacity retention is maintained after 10 cycles at 5C discharge rate between 2.7 V and 4.6 V. The electrochemical impedance spectroscopy(EIS) results show that the current exchange density i0 of the coated sample is higher than that of Li Ni1/3Co1/3Mn1/3O2, which is beneficial to its electrochemical performances. All the conclusions show that the Ni3(PO4)2coating can prominently enhance the high rate performance of the Li Ni1/3Co1/3Mn1/3O2, especially at high cut-off voltage.

On-Line Photoionization Mass Spectrometric Study on Behavior of Ammonia Poisoning on H-Form Ultra Stable Y Zeolite for Catalytic Pyrolysis of Polypropylene

In this work, pyrolysis photoionization time-of-flight mass spectrometry （Py-PI-TOFMS） was applied to study the behavior of ammonia poisoning on H-form ultra stable Y （HUSY） zeolite for the catalytic pyrolysis of polypropylene （PP）. Firstly, ammonia poisoning on HUSY was performed to obtain the suitable catalysts with different strength and amounts of acid sites. Secondly, online photoionization mass spectra for the pyrolysis products of PP and HUSY with various acid strength were recorded at different pyrolysis temperatures. Finally, the formation curves of various pyrolysates of PP/HUSY with the increase of temperature were determined. Our results indicate that the formation temperatures, yields and selectivity of the pyrolysis products of PP demonstrate obvious relationship with the acid strength of HUSY.

State-to-state Photoionization Dynamics of Vanadium Nitride by Two-color Laser Photoionization and Photoelectron Methods

We have conducted a two-color visible-ultraviolet （VIS-UV） resonance-enhanced laser pho- toionization and pulsed field ionization-photoelectron （PFI-PE） study of gaseous vana- dium mononitride （VN） in the total energy range of 56900-59020 cm-1. The VN molecules were selectively excited to single rotational levels of the intermediate VN（D3H0, v＇=0） state by using a VIS dye laser prior to photoionization by employing a UV laser. This two-color scheme allows the measurements of rovibronically selected and re- solved PFI-PE spectra for the VN＋（X2A; v＋=0, 1, and 2） ion vibrational bands. By simulating the rotationally resolved PFI-PE spectra, J＋=3/2 is determined to be the lowest rotational level of the ground electronic state, indicating that the symmetry of the ground VN＋ electronic state is 2A3/2. The analysis of the PFI-PE spectra for VN＋ also yields accurate values for the adiabatic ionization energy for the formation of VN＋（X2A3/2）, IE（VN）=56909.5＋0.8 cm-1 （7.05588±0.00010 eV）, the vibrational fre- quency wc＋=1068.0±0.8 cm-1, the anharmonicity constant wc＋Xe＋=5.8±0.8 cm-1, the rotational constants Be＋=0.6563±0.0005 cm-1 and ae＋=0.0069±0.0004 cm-1, and the equi-librium bond length, re＋=1.529A, for VN＋（X2A3/2）; along with the rotational constants Bc＋=0.6578i0.0028 cm-1 and a＋=0.0085±0.0028 cm-1, and the equilibrium bond length re＋=1.527A for VN＋（X2As/2）, and the spin-orbit coupling constant A=153.3±0.8 cm-1 for VN＋（X2/k5/2,3/2）. The highly precise energetic and spectroscopic data obtained in the present study are valuable for benchmarking the predictions based on state-of-the-art ab initio quantum calculations.