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Zheng J Yamada M Wang Z Aono T Kusakabe M 《Analytical and bioanalytical chemistry》2004,379(3):532-539
An analytical method for determining 239Pu and 240Pu in marine sediment samples, which uses quadrupole ICP-MS, was developed in this work. A simple anion-exchange chromatography system was employed for the separation and purification of Pu from the sample matrix. A sufficient decontamination factor of 1.4×104 for U, which interferes with the determination of 239Pu, was achieved. High sensitivity Pu determination was obtained, which led to an extremely low concentration detection limit of ~8 fg/ml (0.019 mBq/ml for 239Pu; 0.071 mBq/ml for 240Pu) in a sample solution, or an absolute detection limit of 42 fg in a 5 ml sample solution, by using the shield torch technique. Analytical results for the determination of the 239+240Pu and the 240Pu/239Pu ratio in IAEA 368 (ocean sediment) reference material indicated that the accuracy of the method was satisfactory. The method developed was successfully applied to a study of Pu behavior in the sediments from Sagami Bay, Japan. The observed high 240Pu/239Pu ratio in the sediment core indicated that there was additional Pu input derived from close-in fallout in addition to the global fallout. 相似文献
84.
In the visual tracking problem, fusion of visible and infrared sensors provides complementarily useful features and can consistently help distinguish the target from the background efficiently. Recently, multi-view learning has received growing attention due to its enormous potential in combining diverse view features containing consistent and complementary characteristics. Therefore, in this paper, a visible and infrared fusion tracking algorithm based on multi-view multi-kernel fusion (MVMKF) model is presented. The proposed MVMKF model considers the diversities of visible and infrared views and embeds complementary information from them. Furthermore, the multi-kernel framework is used to learn the importance of view features so that an integrated appearance representation is made with regard to the respective performance. Besides, the tracking task is completed with naive Bayes classifier in sophisticated compressive feature domain, considering the high performances of classifier-level and sophisticated feature-level learning for multiple views. The experimental results demonstrate that the MVMKF tracking algorithm performs well in terms of accuracy and robustness. 相似文献
85.
Qian Jia Ruili Zhang Haohao Yan Yanbin Feng Fang Sun Zuo Yang Chaoqiang Qiao Xiaocheng Mou Prof. Jie Tian Prof. Zhongliang Wang 《Angewandte Chemie (International ed. in English)》2023,62(48):e202313420
An accurate detection of lung metastasis is of great significance for making better treatment choices and improving cancer prognosis, but remains a big challenge in clinical practice. In this study, we propose a reinventing strategy to develop a pH-activatable near-infrared (NIR) fluorescent nanoprobe, pulmonary metastasis tracer (denoted as PMT), based on assembly of NIR dye IR780 and calcium phosphate (CaP). By delicately tuning the intermolecular interactions during the assembly process and dye doping content, as well as the synthetic condition of probe, the fluorescence of PMT could be finely adjusted via the tumor acidity-triggered disassembly. Notably, the selected PMT9 could sharply convert subtle pH variations into a distinct fluorescence signal to generate high fluorescence ON/OFF contrast, dramatically reducing the background signals. Benefiting from such preferable features, PMT9 is able to precisely identify not only the tumor sites in orthotopic lung cancer models but also the pulmonary metastases in mice with remarkable signal-to-background ratio (SBR). This study provides a unique strategy to turn shortcomings of traditional dye IR780 during in vivo imaging into advantages and further expand the application of fluorescent probe to image lung associated tumor lesions. 相似文献
86.
合成了Eu(Ⅲ)与α-噻酚甲酰三氟丙酮(HTTA)、三苯基氧化膦(TPPO)和苯甲酸(BA)及其衍生物对甲基苯甲酸(PTA)或对甲氧基苯甲酸(POA)形成的系列配合物.对所合成配合物利用元素分析、红外光谱、扫描电镜与荧光光谱等手段进行了表征.元素分析表明其组成为Eu(BA)(TTA)2TPPO2,Eu(PTA)(TTA)2TPPO2与Eu(POA)(TTA)2TPPO2.测定了配合物Eu(POA)(TTA)2TPPO2在甲醇中的紫外吸收与荧光激发光谱.结果表明,苯甲酸及其衍生物作第二配体加入到Eu3 的配合物中,能得到成本较低的系列鲜艳红色荧光材料,它们的相对荧光强弱顺序是:Eu(POA)(TTA)2TPPO2>Eu(PTA)(TTA)2TPPO2>Eu(BA)(TTA)2TPPO2. 相似文献
87.
化学发光法测定三氯生 总被引:1,自引:0,他引:1
1引言三氯生(2,4,4′-三氯-2-羟基二苯醚)是常用消毒剂,广泛应用于日化产品中。三氯生的大量应用,对河流、湖泊等带来的污染问题受到关注。另外,三氯生合成过程中还可能产生有害的二噁英类物质。定量测定日化产品中三氯生的方法报道较少,有电化学法、高效液相色谱法、紫外分光光度法、毛细管区带电泳法等,未见有化学发光法测定三氯生的报道。研究表明,在荧光素存在下三氯生溶液经光照后,可与氧化剂反应产生化学发光。曲拉通X-100可极大地增强化学发光信号。据此建立了三氯生的化学发光测定新方法。2实验部分2.1仪器与试剂IFFM-D型流动注… 相似文献
88.
Yao Shuhua Wang Shuo Sun Shuyu Shi Zhongliang 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(6):1132-1137
Russian Journal of Physical Chemistry A - Preoxidation process is usually needed in the treatment of arsenic containing water because arsenite (i.e., As(III)) is less easily to be removed by... 相似文献
89.
The partner selection is an important decision problem in the formation of a new virtual enterprise. Using the projection technique, this study introduces an approach to partner selection with linguistic values and intuitionistic fuzzy information under a group decision-making environment. To avoid information loss, there is no aggregations of decision information in this model except ideal decisions as auxiliary decision tools. Comparisons of the suggested methodology with other methods are also made. A numerical example and an experimental analysis are proposed to illustrate the application of the proposed model. 相似文献
90.
Jinfeng Liu Zhongliang Liu Peng Ren Pengshou Xu Xiufang Chen Xiangang Xu 《Acta Physico》2008,24(4):571-575
Quantum well structure film of 6H-SiC/3C-SiC/6H-SiC was fabricated on 6H-SiC (0001) with the substrate temperature of 1350 K by solid source molecular beam epitaxy (SSMBE) through the variation of Si flux rate. The crystal polytypes and luminescent properties of the film were characterized by reflection high energy electron diffraction (RHEED) and photoluminescence (PL), respectively. The results of RHEED indicated that the film was 6H-SiC/3C-SiC/6H-SiC with the quantum well structure. The results of PL excited by He-Gd laser at room temperature showed that there were intense emissions in the range of 480–600 nm, which could not be observed from the substrate. The fitting peaks were consistent with the results calculated from the model of quantum well structure, which showed that such intense emissions were probably from the quantum wells with different widths. 相似文献