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11.
流动注射在线分离富集-火焰原子吸收光谱法测定环境水样中Cr(Ⅲ)和Cr(Ⅵ)的形态 总被引:9,自引:0,他引:9
采用单阀阴离子和阳离子交换树脂微柱并联 ,两柱交替采样逆向洗脱流动注射在线分离富集环境水样中Cr(Ⅲ )和Cr(Ⅵ ) ,分别用 15 %HNO3和 8%NH4 NO3洗脱 ,火焰原子吸收光谱法直接检测。富集 1min时Cr(Ⅲ )和Cr(Ⅵ )的特征浓度分别为 :1 5 0 μg·L- 1 和 1 39μg·L- 1 ,Cr(Ⅲ )和Cr(Ⅵ )检出限 (3σ)分别为 1 0 3μg·L- 1 和 0 5 4 μg·L- 1 ;相对标准偏差 (10 μg·L- 1 )分别为 :3 4 1%和 1 80 % ,分析样品加标回收率在 93 5 %~ 10 7 5 %之间。 相似文献
12.
K. Okada T. Nakamura S. Ohtani M. Wada J. Tanaka H. Kawakami I. Katayama D. Schnier H.A. Schuessler O. Becker F. Arbes G. Werth 《Applied physics. B, Lasers and optics》1996,62(1):91-95
A technique is proposed for injection-seeding control of tunable lasers. It is based on a combination of successive external injection and intracavity self-injection of radiation when the active medium is pumped by dual-step pulses. The technique is tested both experimentally (in the case of Nd:YAG-laser-pumped pulsed dye lasers) and numerically, using a model developed by us. Full conversion of the broadband spectrum into the injected line is achieved for an output energy greater by a factor of about 50 than that managed by means of the traditional injection-seeding technique under identical conditions. 相似文献
13.
H. A. Schuessler E. C. Benck F. Buchinger H. Iimura Y. F. Li C. Bingham H. K. Carter 《Hyperfine Interactions》1992,74(1-4):13-21
The nuclear moments of the neutron-deficient187,188Tl isotopes were determined by measuring the hyperfine structure splittings of the λ=535 nm line in neutral thallium. An optical
efficiency of 2×10−4 photons per radioactive ion was achieved using collinear fast beam laser spectroscopy with a large solid angle fiber optical
array detector. Most of the moments can be interpreted fairly well in the single particle model. 相似文献
14.
The linear combined trap is a superposition of the conventional Paul and Penning traps in one device. Using a four-rod structure, a linear configuration can be constructed. Such a linear combined trap is particularly well suited for catching ions produced externally, since both the effective potential due to the driving RF-field and the DC-magnetic field contribute to the ion confinement. The use of this novel trap for on-line laser and mass-spectroscopy of rare short-lived isotopes is proposed. 相似文献
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Non-relativistic configuration interaction (CI) ab initio calculations using large basis sets have been carried out to determine the potential curves of the first electronic states of Ne2 +, Ar2 + and Kr2 +. The spin—orbit interaction was treated assuming that the spin—orbit coupling constant is independent of the internuclear separation (R). For Ar2 +, calculated dissociation energies and equilibrium separations are in good agreement with experimental results. The calculations for Ne2 + suggest that the lowest vibrational level of the I(1/2u) ground state observed by threshold photoelectron spectroscopy by Hall et al. [1995, J. Phys. B: At. molec. opt. Phys., 28, 2435] and assigned to either ν = 0 or ν = 2 actually corresponds to ν = 4. The calculations also predict the I(1/2g) state of Ne2 + and Ar2 + to possess a double-well potential and that of Kr2 + to be repulsive at short range and to only possess a single shallow well at large internuclear separation. The ab initio calculations provide an explanation for the observation made by Yoshii et al. [2002, J. chem. Phys., 117, 1517] that Kr2 + and Xe2 + dissociate after photoemission from the II(1/2u) state to the I(1/2g) state whereas Ar2 + does not. 相似文献
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At weak force range the two-well Duffing equation has a closed bifurcation region in theparameter plane, inside which there are many different periodic windows. By means ofone-dimensional and two-dimensional symbolic dynamics, these periodic windows and thedynamical behavior of chaotic attractors are analyzed systematically. 相似文献
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