H1+,H2+,H3+和He,Ne,Ar碰撞过程中的巴耳末系Hα,Hβ,Hγ发射

实验利用TN-1710光学多道分析系统(OMA),对H₁⁺,H₂⁺,H₃⁺和He,Ne,Ar碰撞过程中产生的巴耳末系H_α,H_β,H_γ发射进行了测量,入射离子H₁⁺,H₂⁺,H₃⁺的 关键词：     

不同初始温度下H2/O2混合物等离子体的演化

本文对不同初始温度下,H₂/O₂混合物等离子体中主要粒子随时间发展的演化规律进行了数值模拟,得到了放电后等离子体中主要带电粒子和中性粒子密度随时间的变化规律.计算结果表明,H₂/O₂混合物等离子体中主要活性粒子密度随时间的增加减小,化学反应达到平衡所需的时间随初始温度升高逐渐减少. 关键词： 等离子体 化学过程 数值模拟 演化     

SiH4激光等离子体内H谱线的线型研究

本工作利用光学多道分析仪(OMA Ⅲ)测量了脉冲TEA CO₂激光诱发的SiH₄等离子体内H Balmer系的H_α,H_σ和H_γ线的线型。结果表明,三条谱线的FWHM(半值全宽度)随跃迁上能级的主量子数的增加而增加,即△λ_1/2(H_α)<△λ_1/2(H_β)<△λ_1/2(H_γ)。通过对等离子体内各类加宽机制的讨论,得出等离子体内谱线的主要加宽机制为Stark加宽。由H_α线的实验线型与Stark加宽理论线型的拟合,得到等离子体的两个重要参量,平均电子密度N≈10¹⁷cm^-3,电子温度T≈40 000K。由H_β线的时间分辨测量得到等离子体的电子密度随时间的演变曲线。 关键词：     

O2中真实电离和电附系数的确定

本文讨论了确定O₂中真实电离和电附系数的一种新方法。在O₂中加入微量的CO(或H₂)或加入少量的CO₂,测量其混合气体的表观电离系数和表观电附系数随气体含量的变化,便可分别求得O₂的真实电离和电附系数。 关键词：     

电子与H2+离子碰撞中的巴耳末α,β发射

对电子与H₂⁺离子碰撞过程中所产生的激发态进行了实验研究,测得巴耳末α,β发射光谱,研究了激发截面随能量变化的依赖关系,并定性讨论了分解复合机制。 关键词：     

以一组统一的高斯函数为基函数的双原子分子的Hartree-Fock-Roothaan波函数(Ⅱ)——H2和第一列元素的同核双原子体系A2,A2~±和A2

采用文献的一组统一的doublezeta收缩高斯型函数为基函数,从头计算H₂和第一列元素的同核双原子体系的电子波函数和轨道能量、总能量等物理量。电子态包括同核体系的基态A₂,一些低激发态A₂~*和正负离子态A₂~±,A表示周期表中Li到F的各种元素。计算限于闭壳层电子组态或只带一个未填满的开壳层电子组态。作为例子,报道了H₂和几种基态A₂的电子波函数表。 关键词：     

碰撞诱导离解(CID)(Ⅱ)——I2(B3∏o+u)在高振动态(v′=62)的碰撞猝灭机理实验研究

本文研究了B³∏_o+u激发态I₂分子在高振动态v′=62时的碰撞猝灭过程。实验中得到了该能级I₂分子和其自身以及与其他气体分子(He,Ar,Kr,H₂,CO,N₂,O₂,CH₄,NH₃,C₂H₆,CCl₄)的碰撞猝灭速率常数,并且发现,在I关键词：     

H2对N2直流辉光放电电子行为的影响

通过用Monte Carlo方法模拟N₂-H₂ 混合气体直流辉光放电等离子体快电子行为，从不同H₂浓度的电子能量分布函数，电子密度以及e_f-N₂碰撞率等方面，研究了加H₂对氮辉光放电等离子体过程的影响. 研究结果表明: 随着H₂浓度的升高，电子的平均能量增加, 电子密度及e_f-N₂的各种非弹性碰撞率减小; 但在 关键词： 2-H₂辉光放电')" href="#">N₂-H₂辉光放电 Monte Carlo模拟 2碰撞率')" href="#">e-N₂碰撞率     

低温等离子体分解N2/O2/NO气氛中NO试验研究

利用自行设计的介质阻挡放电型低温等离子体反应器,研究了NO初始浓度、O₂初始浓度、放电功率、电源频率等因素对NTP转化N₂/O₂/NO气氛中NO的影响规律。研究发现,NO去除率随功率增大而升高,到达一最大值后随功率增大而降低;NO去除率随O₂初始浓度增加而降低,随NO初始浓度增大而减小。相同放电功率下,同一组分中NO去除率随电源频率的增加而降低,因此相同放电功率下降低电源频率可提高NO去除率。O₂初始浓度不高于5%时,NO_x大部分为NO,NO₂和O₃浓度均随放电功率增大而降低,NO₂、O₃生成量随O₂初始浓度升高而增多。     

O2/CO2气氛下CO对煤焦异相还原NO影响的研究

为揭示O₂/CO₂燃烧过程中高浓度的CO对煤焦异相还原NO的影响,在1073 K温度下使用山西褐煤在卧式炉上进行了实验。分别对O₂/CO₂浓度比及CO浓度下NO的还原特性进行详细实验研究。研究结果表明:在O₂/CO₂气氛下,O₂浓度为30%时具有较高的还原率;相同O₂浓度下O₂/CO₂气氛较空气气氛NO还原率高,表明在CO存在的条件下,高浓度的CO₂会促进NO的还原;当CO浓度从1.5%逐渐升高时,NO的还原率逐渐降低,到CO浓度为5%时,NO还原率比没有加入CO时还要低,而在空气气氛下CO浓度的变化对NO的还原率影响较小。     

双电荷离子He2+与Ne,Ar原子碰撞中的激发态

实验用光学多道分析系统(OMA)测量了He²⁺和Ne,Ar碰撞过程中的发射光谱,结果表明,这些碰撞体系存在着三种激发过程:双电子俘获激发过程、单电子俘获激发过程和直接激发过程。给出了HeI,HeII,NeI,NeII和ArI,ArII谱线的发射截面,并对He²⁺+Ne和He²⁺+Ar两个碰撞体系的发射截面作了一些比较,发现在入射离子速度相同的情况下,后者的发射截面要比前者大得多,并对此进行了定性讨论。OMA的光谱波长范围为200—800nm。入射离子He²⁺的能量范围为140—340keV。 关键词：     

Emission features of Ho ion in Nb2O5, Ta2O5 and La2O3 mixed Li2O-ZrO2-SiO2 glasses

Li₂O-ZrO₂-SiO₂: Ho³⁺ glasses mixed with three interesting d-block elemental oxides, viz., Nb₂O₅, Ta₂O₅ and La₂O₃, were prepared. Optical absorption and photoluminescence spectra of these glasses have been recorded at room temperature. The luminescence spectra of Nb₂O₅ and Ta₂O₅ mixed Li₂O-ZrO₂-SiO₂ glasses (free of Ho³⁺ ions) have also exhibited broad emission band in the blue region. This band is attributed to radiative recombination of self-trapped excitons (STEs) localized on substitutionally positioned octahedral Ta⁵⁺ and Nb⁵⁺ ions in the glass network. The Judd-Ofelt theory was successfully applied to characterize Ho³⁺ spectra of all the three glasses. From this theory various radiative properties, like transition probability A, branching ratio β_r and the radiative lifetime τ_r, for ⁵S₂ emission levels in the spectra of these glasses have been evaluated. The radiative lifetime for ⁵S₂ level of Ho³⁺ ions has also been measured and quantum efficiencies were estimated. Among the three glasses studied the La₂O₃ mixed glass exhibited the highest quantum efficiency. The reasons for such higher value have been discussed based on the relationship between the structural modifications taking place around the Ho³⁺ ions.     

Ion survival probabilities for 3 keV Ar+ scattering from La,Yb, and chemisorbed H2, O2, and H2O on La surfaces

TOF spectra of scattered primary and surface recoiled neutrals and ions for 3 keV Ar⁺ bombardment of clean La and Yb and H₂, O₂, and H₂O saturated La surfaces are presented. The spectra are analyzed in terms of single (SS) and multiple (MS) scattering of the primary ions and surface recoiling (SR) of adsorbate atoms. Measurement of spectra of neutrals + ions and neutrals alone allows determination of scattered ion fractions Y. The Y values for the SS event are high for clean La (37%) and lower for adsorbate covered La (32% for H₂, 13% for O₂, and 8% for H₂O); Yb exhibits a similar behavior, i.e. 16% for clean Yb and 5% for O₂ + H₂O covered Yb. Photon emission accompanying the scattering collision has been observed from clean La and Yb and adsorbate covered La. A preferential inelastic energy loss of 15 ± 3 eV for the SS event has been observed for scattered neutrals as opposed to ions for La and H₂ saturated La at 135°. These results are interpreted within the models for Auger and resonant electronic charge exchange transitions during approach or departure of an ion with a surface and the electron promotions occuring during close atomic encounters where the electron shells are interpenetrating.     

Optical spectroscopy of Ca3Sc2Si3O12, Ca3Y2Si3O12 and Ca3Lu2Si3O12 doped with Pr

The silicates Ca₃Sc₂Si₃O₁₂, Ca₃Y₂Si₃O₁₂ and Ca₃Lu₂Si₃O₁₂, both undoped and doped with Pr³⁺ ions, have been synthesized by solid-state reaction at high temperature. The luminescence spectroscopy and the excited state dynamics of the materials have been studied upon VUV and X-ray excitation using synchrotron radiation. All doped samples have shown efficient 5d-4f emission upon direct VUV excitation of 5d levels, but only Ca₃Sc₂Si₃O₁₂:Pr³⁺ shows luminescence upon interband VUV or X-ray excitation. The VUV excited emission spectra of Ca₃Y₂Si₃O₁₂:Pr³⁺ and Ca₃Lu₂Si₃O₁₂:Pr³⁺ show features attributed to emission from two distinct sites accommodating the Pr³⁺ dopant. The decay kinetics of the Pr³⁺ 5d-4f emission in Ca₃Sc₂Si₃O₁₂:Pr³⁺ upon VUV excitation across the band gap are characterized by decay times in the range 25-28 ns with no significant rise after the excitation pulse. They appear to be faster upon X-ray irradiation than for VUV excitation. Weak afterglow components are attributed to defect luminescence.     

Opto-galvanic spectroscopy of some molecules in discharges: NH2, NO2, H2 and N2

The change of the discharge voltage when laser light crossing the discharge is tuned to a molecular transition has been measured. Experiments have been performed in the wavelength region between 570 nm and 620 nm with discharges in NH₃, NO₂, H₂, N₂, O₂ and argon. Transitions from the ground states of NH₂ and NO₂ and transitions from metastable states of N₂ and H₂ have been detected. The spacial dependence of the opto galvanic in a low pressure dc-discharge of H₂ and N₂ has been studied.     

The origin of K2, Rb2 and Cs2 triplet 13Πg−X3Σ+u bands in discharge

The absorption and emission spectra of potassium, rubidium and caesium low-pressure discharges have been studied at the far blue wings of resonance D2-lines. The observed diffuse bands were attributed to the 1³Π_g?X³Σ⁺_u transition. Experiments revealed the recombination ²P + ²S nature of these bands, and the corresponding rate coefficients were obtained. Energies of the higher excited states as well as the X³Σ⁺_u -state well depths for K₂, Rb₂ and Cs₂ molecules were estimated.     

Electron spectroscopy using excited atoms and photons IX. Penning ionization of CO2, CS2, COS,N2O,H2S,SO2, and NO2

The electron spectra resulting from thermal collisions of He* (predominantly 2³S) metastable atoms with the seven triatomic molecules, CO₂, COS, CS², N₂O H₂S, SO₂ and NO₂, are compared with their respective 584-Å photoelectron spectra using a transmission-corrected electron spectrometer. The normalised relative electronic-state transition probabilities for production of ionic states in Penning ionization and photoionization are reported together with energy shifts (ΔE values) for He*(2³S) Penning ionization. The cross-section for Penning ionization to lower states of NO₂⁺ is extremely low as has been observed in other open shell molecules such as NO and O₂.     

Spectroscopic features of Pr, Nd, Sm and Er ions in Li2O-MO (Nb2O5, MoO3 and WO3)-B2O3 glass systems

Li₂O-MO (Nb₂O₅, MoO₃ and WO₃)-B₂O₃ glasses doped with four rare earth ions, viz., Pr³⁺, Nd³⁺, Sm³⁺ and Er³⁺ (of 1.0 mol% each) were prepared. The glasses were characterized by X-ray diffraction, differential scanning calorimetry, ESR, optical absorption and photoluminescence spectra. From the measured intensities of various absorption bands of these glasses, the Judd-Ofelt parameters Ω₂, Ω₄ and Ω₆ have been evaluated. The Judd-Ofelt theory could successfully be applied to characterize the absorption and luminescence spectra of these glasses. From this theory, various radiative properties like transition probability A, branching ratio β_r, the radiative life time τ_r and the emission cross-section σ^E for various emission levels of these glasses have been determined and reported. An attempt has also been made to throw some light on the relationship between the structural modifications and luminescence efficiencies of all the three glasses. The analysis of the data indicated high non-radiative losses in Nb₂O₅ mixed glasses.     

高电荷态离子N6+与He原子碰撞激发过程的实验研究

利用电子迴旋共振(ECR)多电荷离子源产生的高电荷态离子束和LHT-30VUV真空紫外单色仪,对N⁶⁺与He碰撞激发过程进行研究,观察到三种碰撞激发过程:(1)单电子俘获;(2)双电子俘获;(3)入射离子直接激发过程。 关键词：