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Ultrasensitive Detection of Glyphosate Using CdTe Quantum Dots in Sol-Gel-Derived Silica Spheres Coated with Calix[6]arene as Fluorescent Probes

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American Journal of Analytical Chemistry 2012年第1期3卷 12-18页

作者： Tao Li Yunyou Zhou Junyong Sun Kai Wu 不详

We have developed a simple method for the preparation of highly fluorescent and stable, water-soluble CdTe quantum dots in sol-gel-derived composite silica spheres which were coated with calix[6]arene. The resulting nanoparticles (nps) were characterized in terms of UV, fluorescence and FT-IR spectroscopy and TEM. The results show that the new nps display more intense fluorescence intensity and are more stable than its precursors of the type SiO2/CdTe. Under the optimum, the novel nps exhibit a higher selectivity and ultrasensitive fluorescence probes for the determination of gly-phosate over other pesticides, the fluorescence intensity increase with the concentration of glyphosate in the range from 1.0 to 25.0 nmol/L and the detection limit is low to 0.0725 nmol/L. A mechanism is suggested to explain the inclusion process by a Langmuir binding isotherm.

关键词： Quantum Dots SiO2/CdTe nps C/SiO2/CdTe nps Glyphosate Fluorescence Probes

Object Shift in Akoose： Case Deficiency or Agreement Requirements？

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Psychology Research 2017年第6期7卷 318-329页

作者： Michael Etuge Apuge The University of Maroua Maroua Cameroon

CuO nps对好氧颗粒污泥形成的影响研究

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应用化工 2018年第8期47卷 1581-1586,1599页

作者：周橄郑晓英周翔金梦琦卢丹张远邵晓瑶浅水湖泊综合治理与资源开发教育部重点实验室河海大学环境学院江苏南京210098

采用4个SBR反应器,研究CuO nps用量对好氧污泥颗粒形成及其稳定运行的影响。结果表明,当CuO nps投加浓度0,0.5,1.0 mg/L和2.0 mg/L时,普通活性污泥可以被驯化培养为好氧颗粒污泥,颗粒污泥出现时间分别为26,24,28,27 d。0.5 mg/L的CuO NP... 详细信息

采用4个SBR反应器,研究CuO nps用量对好氧污泥颗粒形成及其稳定运行的影响。结果表明,当CuO nps投加浓度0,0.5,1.0 mg/L和2.0 mg/L时,普通活性污泥可以被驯化培养为好氧颗粒污泥,颗粒污泥出现时间分别为26,24,28,27 d。0.5 mg/L的CuO nps能刺激微生物生长,增加污泥浓度。COD和TN去除效果受CuO nps影响较小,TP去除效果受CuO nps影响较大。当CuO nps投加浓度为0,0.5,1.0 mg/L和2.0 mg/L时,成熟颗粒污泥对TP的去除率分别为71.21%,70.34%,69.33%和60.84%。通过高通量测序发现,4个系统特有的OUT数目分别为1 637,1 562,1 958和1 584,分别占总样品的16.5%,15.75%,19.74%和15.97%,表明好氧污泥颗粒化进程中,CuO nps的投加浓度对颗粒污泥微生物群落分布具有较大影响。污泥微生物种群结构分析,发现当CuO nps投加浓度为2 mg/L时,变形菌门中包含大部分聚磷菌的β变形菌纲(β-Proteobacteria)比例下降明显,污泥颗粒化进程中,SBR4反应器除磷性能恶化的主要原因正是来自高浓度CuO nps对β变形菌纲中微生物生长的抑制。

关键词：序批示反应器 CuO nps 好氧颗粒污泥形成高通量测序

Tea Identification through Surface-Assisted Laser Desorption/Ionization Mass Spectrometry

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International Journal of Analytical Mass Spectrometry and Chromatography 2013年第1期1卷 11-21页

作者： Wen-Tsen Chen Huan-Tsung Chang Department of Chemistry National Taiwan University Taipei Taiwan

We have applied surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) usingtitanium dioxide nanoparticles(TiO2nps)as the matrix and captopril (CAP) as internal standard for the determination of the concentrations of theanine and four catechins—catechin, (_)-epigallocatechin (EGC), (_)-epicatechin gallate (ECG), and (_)-epigallocatechin gallate (EGCG).Under the optimal conditions (240 nM TiO2 nps and 10 μM CAP), this SALDI-MS approach provides linearity of 0.3– 80 (r= 0.990), 1.2–100 (r= 0.987), 4–120 (r= 0.995), 6–120 (r= 0.983), and 2–120 μM (r= 0.991) for theanine, catechin, EGC, ECG, and EGCG, respectively. The limits of detection (LODs;S/N = 3)for theanine, catechin, EGC, ECG, and EGCG provided by this SALDI-MS approach are 0.1, 0.35, 1.0, 1.45, and 0.5 μM, respectively. This approach provides spot-to-spot and batch-to-batch variations of less than 10% and 13%, respectively, for the analysis of tea samples.With advantages of simplicity, accuracy, precision, and great reproducibility, we have applied the SALDI-MS approach for the analysis of tea samples, with identified peaks for theanine, catechin, EGC, ECG, and EGCG. Tea samples from Taiwan and four other areas have various SALDI-MS profiles, showing their potential for differentiation of tea samples from different sources. Our result also shows that tea samples harvested in different seasons and counties in Taiwan provide significantly different MS profiles. The amounts of theanine and EGC in the Oolong tea from Lishan are much higher than those in the other tea samples.

关键词： Tea Samples TiO2 nps SALDI-MS Catechins Theanine Captopril

Investigation of the Impact of Calcinations Temperature on the Prop-erties of Ba Doped HfO2 Nano-rods

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Modern Electronic Technology 2018年第2期2卷 35-40页

作者： J. Manikantan H. B. Ramalingam B. Chandar Shekar Sri Ranganathar Institute of Engineering and Technology Coimbatore Tamilnadu 641110 India Department of Physics Government Arts College Udumalpet Tamilnadu 642126 India Nanotechnology Research Lab Kongunadu College of Arts and Science Coimbatore Tamilnadu 641029 India

Barium doped hafnium oxide nanoparticles were synthesized by an easy co-precipitation method. FTIR analysis and EDX investigation shows the purity and stoichiometric composition of hafnium oxide nanoparticles. XRD investigation exhibit the as syn-thesized nanoparticles are amorphous in nature and calcined barium doped hafnium oxide nanoparticles have the monoclinic phase structure with the mean crystallite size was around 15 nm. TEM analysis shows the development of crystalline Nano-rods. The Na-no-rod formations signify the possibility of its use in applications of sensor. Ultra violet visible spectroscopy investigation shows that the band gap of the nanoparticles is noticed between 5.4-5.14 eV. The visible and NIR of barium doped hafiniura oxide nanoparticles indicated high reflectance, which may possibly be employ as an antireflection coating in solar cells applications and high absorbance ultra violet region signify the viability of make use of the prepared nanoparticles could be used in Opto-electronic device applica-tions.

关键词： Co-precipitation Ba-Hf02 nps Nano-rods XRD Optical materials

The non-point source (NFS) information system based on remote sensing and GIS and its preliminary application

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Chinese Science Bulletin 2000年第S1期45卷 71-75,116页

作者： WANG YunpengGuangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China

A non-point source information system (npsIS) has been constructed by use of remote sensing and GIS technology, and a construction method of npsIS introduced with Shenzhen as an example. With the remote sensing land-using images as an environment unit, the analysis modules based on npsIS are built through combining the nps model with npsIS, and the preliminary nps calculation and analysis performed.

关键词： remote sensing GIS non-point source nps information system.

纳米氧化铜(CuO nps)对紫花苜蓿幼苗根系活性氧(ROS)、抗氧化酶活性和根系活力的影响

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生态毒理学报 2016年第5期11卷 117-124页

作者：刘振国王天慧王伟上海大学生命科学学院生命科学实验中心上海200444 上海市能源作物重点实验室上海200444

根系通常是植物直接受到外界环境物质(如重金属离子和纳米金属氧化物)毒害的主要器官。本研究以紫花苜蓿的幼苗为实验材料,探讨了CuO nps胁迫对紫花苜蓿幼苗根系的活性氧(ROS)积累、抗氧化酶活性和根系活力的影响。研究结果表明:(1)不... 详细信息

根系通常是植物直接受到外界环境物质(如重金属离子和纳米金属氧化物)毒害的主要器官。本研究以紫花苜蓿的幼苗为实验材料,探讨了CuO nps胁迫对紫花苜蓿幼苗根系的活性氧(ROS)积累、抗氧化酶活性和根系活力的影响。研究结果表明:(1)不同浓度的CuO nps对紫花苜蓿幼苗根系H_2O_2和O-2·含量具有显著影响。随CuO nps浓度增大,紫花苜蓿幼苗根系中H_2O_2和O-2·整体上呈现先增大后减少的趋势,除了0.00125 mol·L^(-1)CuO nps浓度下紫花苜蓿幼苗根系中H_2O_2含量比对照减少外,其他浓度下的H_2O_2和O-2·的含量都比对照有所增加,并且H_2O_2和O-2·的含量都是在0.0125 mol·L^(-1)CuO nps浓度下达到最大值。(2)不同浓度的CuO nps对紫花苜蓿幼苗根系抗氧化酶活性具有显著影响。随CuO nps浓度增大,紫花苜蓿幼苗根系中SOD、POD、APX和CAT酶的活性都呈现先增大后减少的趋势,其中,SOD和POD、APX、CAT酶的活性分别是在0.00625、0.0125、0.0625 mol·L^(-1)CuO nps处理下达到最大,表明这些抗氧化酶在清除根系中的活性氧方面表现出较强的协同性和补偿性。(3)不同浓度的CuO nps对紫花苜蓿幼苗根系活力具有显著的影响。随着CuO nps浓度的增加,紫花苜蓿幼苗根系活力逐步升高,这是一种生物适应性应激响应的体现。

关键词： CuO nps 紫花苜蓿活性氧抗氧化酶根系活力

Tagging Accuracy Analysis on Part-of-Speech Taggers

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Journal of Computer and Communications 2014年第4期2卷 157-162页

作者： Semih Yumusak Erdogan Dogdu Halife Kodaz Computer Engineering Department KTO Karatay University Konya Turkey Computer Engineering Department Selcuk University Konya Turkey Computer Engineering Department TOBB University of Economics and Technology Ankara Turkey

Part of Speech (POS) Tagging can be applied by several tools and several programming languages. This work focuses on the Natural Language Toolkit (NLTK) library in the Python environment and the gold standard corpora installable. The corpora and tagging methods are analyzed and com- pared by using the Python language. Different taggers are analyzed according to their tagging ac- curacies with data from three different corpora. In this study, we have analyzed Brown, Penn Treebank and nps Chat corpuses. The taggers we have used for the analysis are;default tagger, regex tagger, n-gram taggers. We have applied all taggers to these three corpuses, resultantly we have shown that whereas Unigram tagger does the best tagging in all corpora, the combination of taggers does better if it is correctly ordered. Additionally, we have seen that nps Chat Corpus gives different accuracy results than the other two corpuses.

关键词： POS Tagger Brown Corpus Penn Treebank Corpus nps Chat Corpus

Global Sensitivity Analysis in Physiological Systems

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Applied Mathematics 2020年第3期11卷 119-136页

作者： Tahmineh Azizi Robert Mugabi Institute of Computational Comparative Medicine Department of Anatomy and Physiology Department of Mathematics Kansas State University Manhattan KS USA Department of Diagnostic Medicine and Pathobiology College of Veterinary Medicine Kansas State University Manhattan KS USA

Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that caused to do a lot of efforts to make them more accurate. Current work studies the process of drug and nanoparticle (nps) distribution throughout the body which consists of a system of ordinary differential equations. We use a tri-compartmental model to study the perfusion of nps in tissues and a six-compartmental model to study drug distribution in different body organs. We have performed global sensitivity analysis by LHS Monte Carlo method using PRCC. We identify the key parameters that contribute most significantly to the absorption and distribution of drugs and nps in different organs in body.

关键词： Global Sensitivity Analysis Latin Hypercube Sampling (LHS) Partial Rank Correlation Coefficient (PRCC) Physiological Systems Drug and nps Distribution