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991.
原子吸收法测定水样中的Cu、Zn、Cd、Pb——离子交换树脂预浓缩法庞文生(平顶山环保学校河南平顶山467000)韩富贵燕青枝(平顶山师范专科学校化学系)关键词原子吸收分光光度法离子交换树脂预浓缩Cu、Zn、Cd、Pb测定中图分类号O657.39当水...  相似文献   
992.
大孔膦酸树脂吸附钇的研究   总被引:6,自引:0,他引:6  
大孔膦酸树脂吸附钇的研究舒增年熊春华(丽水师范专科学校化学系浙江323000)林峰(杭州大学化学系杭州310028)关键词大孔膦酸树脂钇吸附机理中图分类号O614.322本文在HAc-NaAc体系中,研究了树脂吸附钇的性能及其机理,获得了诸多的结果,...  相似文献   
993.
氟化铟基玻璃中Er^3+离子光谱性质的研究   总被引:6,自引:0,他引:6  
王英剑  林凤英 《光学学报》1997,17(2):55-160
测定了掺Er^3+氟化铟基玻璃的吸收光谱,激发光谱和荧光光谱,计算了该玻璃的强度参数Ω(t=2,4,6),给出了Er^3+离子的发光特性的计算结果,并与掺Er^3+的氟锆酸盐玻璃做比较,解释了基质玻璃对Er^3+离子发光特性的影响。  相似文献   
994.
995.
离子辅助沉积氧化物薄膜的光学特性   总被引:1,自引:1,他引:0  
考察了不同离子、离子能量、离子束流密度等制备参数对离子辅助沉积的TiO_2、ZrO_2和SiO_2薄膜的折射率、吸收和激光损伤阈值等光学特性的影响。  相似文献   
996.
A radioisotope ion implanter has been developed using a cesium-sputtering, negative ion source, which offers versatility and sustained operation. Employing the molecular 111In16O ion, μCi activities of the radioisotope probe 111In/Cd have been implanted into different material hosts. The implanted tracer activity has been shown to be sufficient for LTNO, NMRON and PAC. A new NMRON resonance for 111InAg was observed at 75.08 MHz. In2O3 powder performed well as the radioisotope carrier in the ion source, with the ratio of radioisotope and parasitic ion current being typically 4 × 10−4.  相似文献   
997.
A simple, accurate, precise and sensitive method has been developed for the determination of Vardenafil (Vd) using direct coupled plasma atomic emission spectrometry. The ion associates formed as a result of the reaction of vardenafil with ammonium reineckate, Mn(II) and Co(II) thiocyanates and sodium cobaltinitrite are precipitated. The solubility of the solid complexes under the optimum conditions of pH and ionic strength was studied. Saturated solutions of each ion associate at different temperatures under the optimum precipitation conditions were prepared, and the metal ion content in the supernatant was determined. The solubility products were thus calculated at different temperatures, and the thermodynamic parameters ΔH, ΔG and ΔS were calculated. The method has been used for the determination of vardenafil (1.36–68.32 μg·mL−1) in pure solutions and in Levitra tablets.  相似文献   
998.
The oxidation of Ni(1 0 0) and Ni(1 1 1) at elevated temperatures and large oxygen exposures, typical of the methods used in the preparation of NiO(1 0 0) films for surface studies, has been investigated by medium energy ion scattering (MEIS) using 100 keV H+ incident ions. Oxide film growth proceeds significantly faster on Ni(1 1 1) than on Ni(1 0 0), but on both surfaces oxide penetration occurs to depths significantly greater than 100 Å with total exposures of 1200 and 6000 L respectively. The metal/oxide interface is extremely rough, with metallic Ni extending to the surface, even for much thicker oxide films on Ni(1 1 1). On Ni(1 1 1), NiO growth occurs with the (1 0 0) face parallel to the Ni(1 1 1) surface and the close-packed 〈1 1 0〉 directions parallel. On Ni(1 0 0) the MEIS blocking curves cannot be reconciled with a single orientation of NiO(1 0 0) (with the 〈1 1 0〉 directions parallel) on the surface, but is consistent with the substantial orientational disorder (including tilt) previously identified by spot-profile analysis LEED.  相似文献   
999.
The anomaly of ion emission at laser irradiation of targets measured by Badziak et al. was analyzed on the background of the extensive research in the past. In contrast to the irradiation with lasers of longer than 100 ps pulse duration, a drastic decrease of the maximum ion energies was measured with ps pulses. Very strange was the observation that the number of emitted fast ions was intensity independent. The usual ponderomotive or relativistic self-focusing theory and related processes could not explain the results. Instead a direct interaction within the skin depth of the irradiated target was concluded. This model confirms the plane geometry nonlinear force interaction in the ps range producing fast plasma blocks moving perpendicular off or into the target. The block moving into the target opens a new scheme of laser fusion by modifying the experiments of Norreys et al. The use of relatively low subrelativistic laser intensities for the new scheme of laser fusion is evaluated on the background of the long years studies of nonlinear force driven plasma blocks and earlier interpenetration fusion reactions for providing the parameters for expected fusion gains much higher than the experiment of Norreys et al. for a fusion power scheme.  相似文献   
1000.
Er3+,Yb3+共掺磷酸盐玻璃沟道波导放大器   总被引:11,自引:6,他引:5  
在自行研制的Er3 ,Yb3 共掺磷酸盐玻璃基质上用离子交换方法制作出沟导光波导放大器。在110mW的抽运功率下(抽运光波长为980nm),在1.8cm长的器件上获得了3.8dB的小信号(信号光波长为1.55μm)增益,单位长度上的增益为2.1dB/cm。  相似文献   
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