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781.
高盐试样中金属离子的固相萃取分离和测定 总被引:1,自引:0,他引:1
采用NOBIAS chelate-PA1吸附剂固相萃取法分离高盐试样中的V、Fe、Cd、Co、Cu、Zn、U和Th等8种金属离子,并用等离子体原子发射光谱仪(ICP-AES)和等离子体质谱仪(ICP-MS)对被分析物进行了测定.条件实验表明,当样品溶液的pH在5~6时,各元素可以在树脂上达到定量回收;3mL浓度为3mol/L的硝酸可将吸附的离子洗脱完毕;元素浓度在0~1.0μg/mL的范围内可得到定量回收,曲线呈线性关系.树脂的吸附容量为2.5mmol(Cu)/g干树脂.该方法应用于聚变堆用氧化锂球和生物样品海带中V、Fe、Cd、Co、Cu、Zn、U和Th等8种微量元素的测定,结果可靠. 相似文献
782.
In this study, simultaneous brightness contrast was investigated using three different devices: 2D (paper), 3D (space), and D-up. The paper stimuli were made by printing papers, the space stimuli were produced by illumination in a two-rooms experimental booth, and the D-up stimuli were shown to subjects using a D-up viewer. The brightness of test patches was judged by the amounts of whiteness and blackness. The results were different among the devices; however, if the whiteness of the test patches was plotted for the luminance contrast of the test patch versus the surround, all the data points were expressed by nonlinear equations. Data from the space stimuli were expressed by only one equation; those from the paper stimuli were also expressed by the nonlinear equation but with different coefficients for each test patch. The results from D-up were between those of the space and paper experiments. All the results were explained in relation to the hypothesized illuminated space over the surrounds. The difference among devices was explained by the whiteness of the surround being transferred to the illumination. 相似文献
783.
Ion exchange equilibria of alkali metal ions (Li+, Na+, K+,, Rb+, and Cs+)H+, systems have been studied in MNO-j-HNOj media with ionic strength of 0.1 at 30, 45 and 60 °C on tin(IV) antimonate as a cation exchanger. The ion exchange isotherms have been measured for both forward and backward reactions by the batch technique. The isotherms showed S-shaped curves for all exchange systems studied. The selectivity coefficients (logarithmic scale) vary with the equivalent fraction XM of alkali metal ions in the exchanger and give two linear functions of XM with a break point (XM= 0.14, except 0.04 for Li+, /H+) indicating two different exchanging sites. The selectivity sequence, Na+, ? K+, ? Rb+, ? Cs+, ? ? Li, holds in the range of Xu= (0 - 0.04) and the sequence, Cs < Rb +, ? K +, ? Na +, < Li +, applies when XM is higher than 0.14. Hypothetical thermodynamic data on “zero loading” of the ion exchange reaction was evaluated. 相似文献
784.
Isamu Sato Koji Maeda Mitsuo Suto Masahiko Osaka Toshiyuki Usuki Shin-ichi Koyama 《Journal of Nuclear Science and Technology》2013,50(4):580-587
Penetration behavior of radionuclides such as 137Cs into dried concrete material, dried mortar material and epoxy paint for a few dozen days was observed using a solution containing fission products extracted from irradiated fuels to obtain fundamental information on the radionuclide penetration rate and depth. Hardly any radionuclides could penetrate into the epoxy paint. The radionuclide solution penetrated into concrete and mortar materials to a depth of a few millimeters for a few dozen days. The penetration behavior observed near the surface of concrete and mortar materials was similar to the diffusion of nuclides in media such as water-saturated concrete, bentonite and cement materials. 相似文献
785.
Hideo Harada Atsushi Kimura Fumito Kitatani Mitsuo Koizumi Harufumi Tsuchiya Bjorn Becker 《Journal of Nuclear Science and Technology》2013,50(6):837-843
Neutron resonance densitometry (NRD) is a non-destructive analysis method, which can be applied to quantify special nuclear materials (SNM) in small particle-like debris of melted fuel that are formed in severe accidents of nuclear reactors such as the Fukushima Daiichi nuclear power plants. NRD uses neutron resonance transmission analysis (NRTA) to quantify SNM and neutron resonance capture analysis (NRCA) to identify matrix materials and impurities. To apply NRD for the characterization of arbitrary-shaped thick materials, a generalized method for the analysis of NRTA data has been developed. The method has been applied on data resulting from transmission through thick samples with an irregular shape and an areal density of SNM up to 0.253 at/b (≈100 g/cm2). The investigation shows that NRD can be used to quantify SNM with a high accuracy not only in inhomogeneous samples made of particle-like debris but also in samples made of large rocks with an irregular shape by applying the generalized analysis method for NRTA. 相似文献
786.
The optical path difference (OPD) and amplitude of a sinusoidal wavelength scanning (SWS) are controlled with a double feedback control system in an interferometer, so that a ruler marking every wavelength and a ruler with scales smaller than a wavelength are generated. These two rulers enable us to measure an OPD longer than a wavelength. A liquid-crystal Fabry-Perot interferometer (LC-FPI) is adopted as a wavelength-scanning device, and double sinusoidal phase modulation is incorporated in the SWS interferometer. Because of a high resolution of the LC-FPI, the upper limit of the measurement range can be extended to 280 microm by the use of the phase lock where the amplitude of the SWS is doubled in the feedback control. The ruler marking every wavelength is generated between 80 microm and 280 microm, and distances are measured with a high accuracy of the order of a nanometer in real time. 相似文献
787.
Kensuke Osamura Sinya Kobayashi Masaharu Nagano Mitsuo Hirata Shuichi Adachi 《Electrical Engineering in Japan》2011,174(3):45-52
A new shift‐by‐wire system having a standby mechanical link with backlash is proposed. The link directly connects the select lever and the manual lever of the automatic transmission in case of emergency. Thus, it is necessary to keep the backlash free during normal operations without generating a force. The angles of the manual lever driven by an actuator should follow the angles of the select lever exactly and quickly. A two‐degree‐of‐freedom model matching control is developed to meet this requirement. It is shown that the backlash is kept free during the range select operation. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(3): 45–52, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21049 相似文献
788.
In a previous in vitro study, (-)-camphor (1) was examined by incubation with human liver microsomes, and the oxidative metabolites thus formed were analyzed using gas chromatography-mass spectrometry. However, thus far, no large-scale biotransformation using recombinant human P450 has been performed. Here, the biotransformation of compound 1 has been investigated by using Salmonella typhimurium OY1002/2A6 expressing human CYP2A6 and human NADPH-P450 reductase as a biocatalyst. Compound 1 (400 mg) was converted to (1S,5S)-(-)-5-exo-hydroxycamphor (2) (30.4 mg) and (1S,7S)-(-)-8-hydroxycamphor (3) (2.4 mg) by S. typhimurium OY1002/2A6. This is the first report to show that large quantities of metabolites 2 and 3 can be produced by S. typhimurium OY1002/2A6 expressing human CYP2A6 and NADPH-P450 reductase. 相似文献
789.
Micro turning tools with outside diameters of 25–50 μm were fabricated using cemented tungsten carbide by electrical discharge machining and used for micro boring and micro face grooving. The new process used could improve the hole circularity down to 0.25 μm and provide smooth-finished surfaces. From a set of experiments, the limit depth of cut and feed rate that can prevent tool breakage were determined. Compared with previous studies, the current study paved the way for applying removing processes with micro tools to boring and face grooving. 相似文献
790.
In spinal fixation devices, the Young's modulus of the metallic implant rod should be not only sufficiently low to prevent stress shielding for the patient but also sufficiently high to suppress springback for the surgeon. This paper proposes a novel function of biomedical titanium alloys—self-adjustment of Young's modulus. Deformation-induced ω phase transformation was introduced into β-type titanium alloys so that the Young's modulus of only the deformed part would increase during operation, while that of the non-deformed part would remain low. The Young's modulus increase by deformation was investigated for a binary Ti-12Cr alloy. This alloy successfully underwent deformation-induced ω phase transformation and exhibited the increase in the Young's modulus by deformation. 相似文献