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微乳液-1-(2-吡啶偶氮)-2-萘酚体系测定Cd(Ⅱ) 总被引:7,自引:0,他引:7
研究了O/W型阴离子微乳液十二烷基硫酸钠(SDS)/正丁醇(n-C4H9OH)/正庚烷(n-C7H16)/H2O对Cd(Ⅱ)与1-(2-吡啶偶氮)-2-萘酚(PAN)显色体系的增敏增稳作用,试验结果表明,其灵敏度为ε^545=1.93*10^4L.mol^-1.cm^-1,与相同含水量的SDS胶束体系(ε^545=1.15*10^4L.mol^-1.cm^-1)比较,其测定灵敏度显著增加,用于香烟样品分析,结果满意。 相似文献
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利用相干受激Raman抽运,选择性地激发C2H2分子(X~1Σg v2=1,J")单一振转态.在Ra-man泵浦与探测激光不同偏振条件下,获得紫外探测激光诱导的A1Au(v3=1)-(X~1Σg v2=1,J")荧光增益光谱,从而研究了C2H2分子单一振转态的光学ACStark效应和mj的定向分布A0(1),利用stark线型加宽数值模型,从理论上计算得到的Rarnan线型与实验结果进行比较,二者符合程度相当好. 相似文献
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用YAG四马SO2分子从电子基态X^1A1激励到电子激发态A^1A格B^1B1的高振动耦合区,获得了320-380nm范围内SO2(B^1B1→X^1A11)的激光诱导荧光色散谱,并给出初步标识:提出一个三能太模型来处理266nm激光激励的SO2(X^1A1,A^1A2,B^1B1)体系的态间转移,并获得了A态和B 高振动能区的耦合系数ζ及耦合达到动态平衡的弛豫时间τ,发现二者反映的是被研究体系的 相似文献
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测得并解析了2个蝶状铁硒取代衍生物(μ-p-MeC6H4Se)2Fe2(CO)2(Ph2PCH2CH2PPh2)(A)和(μ-p-MeC6H4Se)2Fe2(CO)4(cis-Ph2PCH=CHPPH2)(B)的^1H-^1HCOSY谱和^1H-^15CCOSY谱以及A的^1H-^1HNOESR谱,从而进一不确证了它们的结构。 相似文献
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翁维正 《高等学校化学学报》1994,15(2):173-177
采用NMR方法考察了室温和低温(-78~-60℃)下Pd2X2(dpm)2(X=NCO^-,CH3CO^-2,SCN^-和NO^-3,dpm=Ph2PCH2PPh2)与H2S在CD2Cl2或CDCl3中的反应。结果表明,在X=NCO^-和CH3CO^-2的情况下,H2S优先与这些Pd配合物的阴离子作用生成相应的共轭酸HX和Pd2(SH)2(dpm)2,后者在H2S存在下又进一步转化为Pd2(SH) 相似文献
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用266nm激光光解CHBr3分子产生CH(C)态自由基,通过测量CH(C^2Σ^+→X^2Ⅱ)的总荧光信号强度来测定室温下O2、N2、n-C5H12、n-C6H14和n-C7H16对CH(C2Σ^+,v′=0)的猝灭常数。结果表明,这些碰撞伴侣(O2和N2例外)对CH(X、A、B和C)的反应或猝灭速率常数k存在下列关系:k(X)〉k(B)〉k(A)≈k(C),且烷烃分子对CH(C)态的猝灭速率常 相似文献
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Efficient Coherent Population Transfer of D2 Molecules by Stark-induced Adiabatic Raman Passage
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Preparation of a high flux of hydrogen molecules in a specific vibrationally excited state is the major prerequisite and challenge in scattering experiments that use vibrationally excited hydrogen molecules as the target. The widely used scheme of stimulated Raman pumping suffers from coherent population return which severely limits the excitation efficiency. Re-cently we successfully transferred D2 molecules in the molecular beam from (v=0, J=0) to (v=1, J=0) level, with the scheme of Stark-induced adiabatic Raman passage. As high as 75% of the excitation efficiency was achieved. This excitation technique promise to be a unique tool for crossed beam and beam-surface scattering experiments which aim to reveal the role of vibrational excitation of hydrogen molecules in the chemical reaction. 相似文献
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Condylis PC Hudson JJ Tarbutt MR Sauer BE Hinds EA 《The Journal of chemical physics》2005,123(23):231101
We have measured the Stark shift of the A2Pi(1/2)-X2Sigma+ transition in YbF. We use a molecular beam triple resonance method, with two laser transitions acting as pump and probe, assisted by an rf transition that tags a single hyperfine transition of the X state. After subtracting the known ground state Stark shift, we obtain a value of 70.3(1.5) Hz/(V/cm)2 for the static electric polarizability of the state A2Pi(1/2) (J=1/2),f by fitting our data to a purely quadratic Stark shift in the interval 0-5 kV/cm. A more exact analysis that does not assume a perfectly quadratic Stark effect yields the value mu(e)=2.48(3) D for the electric dipole moment of the A2Pi(1/2)(v=0) state. 相似文献
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The energy-transfer dynamics of high-pressure molecular H(2) gas initially prepared in the |X (1)Sigma(g) (+),v = 1,J = 1 state using stimulated Raman pumping are probed with rotational Raman scattering. A computer simulation that incorporates the effects of collision-induced vibrational energy transfer is described and used to fit the experimental Raman scattering results obtained as a function of the pump/probe delay time. The 4.78 x 10(-14) +/- 3.85 x 10(-16) cm(3) s(-1) molecule(-1) vibrational energy-transfer rate for decay from the |X (1)Sigma(g) (+),v = 1,J = 1 >state compares well with other lower-pressure studies. 相似文献
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Tian-gang Yang Long Huang Tao Wang Chun-lei Xiao Dong-xu Dai Xue-ming Yang 《化学物理学报(中文版)》2017,30(6):614-618
We report the preparation of D2 molecules in v=2 level in molecular beam condition. A single longitudinal mode laser system was used for excitation of D2 from (v=0, j=0) to (v=2, j=0) with the scheme of stimulated Raman pumping. An excitation efficiency of 25.2% has been achieved, which was determined by the scheme of resonance-enhanced multiphoton ionization. Dependence of relative excitation efficiency on laser energy has been measured. We found that the increasing rate of excitation efficiency became slower as pulse energy of Stokes laser increase, while the excitation efficiency still increases approximately linearly with pump pulse energies up to 60 mJ. The spectral line shapes of Raman transition was also measured at different laser energies and considerable dynamical Stark effect was observed. A single peak was found on the three dimension surface of relative excitation efficiency, indicating the process occurred in the present study is a process of stimulated Raman pumping instead of stimulated adiabatic Raman passage. 相似文献
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将线性三原子分子离子CS2+的对称伸缩振动简化为SC和S之间的简谐振动, 用谐振子的势能曲线和波函数对CS2+分子离子 C2Σg+和 B2Σu+电子态(对称伸缩)振动能级间跃迁的Franck-Condon因子进行了计算, 得到的结果与 C2Σg+←B2Σu+跃迁的光解离谱实验强度进行了比较, 对前人给出的分子数据(转动常数、分子平衡核间距)进行了验证和分析, 讨论了经由 C2Σg+←B2Σu+电子态振动能级间跃迁的光解离机理. 相似文献
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When stimulated Raman pumping (SRP) is applied to a stream of isolated molecules, such as found in a supersonic molecular beam expansion, we show that SRP can neither saturate nor power broaden a molecular transition connecting two metastable levels that is resonant with the energy difference between the pump and Stokes laser pulses. Using the optical Bloch-Feynman equations, we discuss the pumping of the hydrogen molecule from H(2) (v = 0, J = 0, M = 0) to H(2) (v = 1, J = 2, M = 0) as an illustration of how coherent population return severely reduces the SRP pumping efficiency unless the pump and Stokes laser pulses are applied with an appropriate relative delay and ratio of intensities. 相似文献
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An intracavity Stark cell was used to observe inverse Lamb dips of five transitions of the 15NH3v2 band, saturated by CO2 laser lines. Accurate values of the electric dipole moment of v2 = 1, (J,K) = (4,4); (7,7); (8,8) and (11,9) states and of the (J,K) = (5,3) vibrational ground state have been obtained. 相似文献
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The reactions of alkaline earth metal atoms, Mg(3s3p 1P1) and Ca(4s4p 1P1), with H2(v = 1, j) are studied using a pump-probe technique combined with stimulated Raman pumping and coherent anti-Stokes Raman spectroscopy. For the Ca(4 1P1) case, the energy deposited in the v = 1 level enlarges the H2 bond distance to help facilitate the reaction without opening an additional pathway. For the Mg(3 1P1) case, the vibrational excitation of H2 leads to enhancement of the low rotational component of the rotational distribution and the MgH(v = 0)/MgH(v = 1) ratio. These results can be predicted with quasi-classical trajectory calculations and interpreted with a kinematic collision model. 相似文献
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Danijela Čurman Petra Živec Ivan Leban Iztok Turel Anna Polishchuk Karel D. Klika Emiliya Karaseva Vladimir Karasev 《Polyhedron》2008
A novel europium complex of fluoroquinolone ciprofloxacin (cfqH) with formula [Eu(cfqH)(cfq)(H2O)4]Cl2 · 4.55H2O (1) was synthesized and its crystal structure determined by X-ray crystallography. The coordination number of europium is eight and in this structure two bidentate, O,O-bonded quinolone molecules and four aqua ligands are coordinated to the metal. One molecule of quinolone is anionic whereas the other is zwitterionic. Additionally, two chloride ions are also present in the structure to compensate the charge of the europium(III) whilst disordered solvent water molecules too are present. The spectral properties (IR, Raman, luminescence) of compound 1 were studied. Analysis of the Stark structure of the luminescence spectra was carried out and the scheme of the electronically excited states and photophysical processes of compound 1 was arranged. The spectral properties show that europium–ciprofloxacin complexes could be suitable for various applications based on their solution-state stability as measured by 1H and 19F NMR. 相似文献
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A supersonic molecular beam of iron monohydride, FeH, has been generated using a laser ablation/chemical reaction scheme and probed at near-natural linewidth resolution by optical Stark spectroscopy utilizing laser-induced fluorescence detection. The observed Stark splitting in Q(3.5) and R(3.5) lines of the F4delta(7/2) <-- X4delta(7/2) (1,0) transition were analyzed to determine values for the magnitudes of the permanent electric dipole moments, absolute value(mu), which were found to be 2.63(3) and 1.29(3) D for the X4delta (v = 0) and F4delta (v = 1) states, respectively. A comparison with ab initio theoretical predictions is made. The lambda doubling in the low-J levels of the F4delta(7/2) (v = 1) state is also modeled. 相似文献