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211.
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气相色谱—微波等离子体发射光谱法研究农药1605与人唾液的相互作用 总被引:3,自引:0,他引:3
用GC-AED联用技术研究了农药1605,得到1605所含六种元素的元素色谱图,并用该方法研究了人唾液与1605的相互作用。 相似文献
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利用甘氨酸燃烧法制备了ZnOMgO纳米复合材料,并在不同温度进行热处理.通过X射线衍射、扫描电子显微镜和傅里叶变换红外吸收谱,对其升温过程中的结构变化进行了表征,研究了热处理温度对样品室温光致发光行为的影响.结果表明,复合材料的发光性能与纯ZnO相比有很大改善,经900℃热处理的纳米复合材料,其发射谱由一个强紫外发射带(峰值385nm)构成;当热处理温度低于900℃时,发光强度随热处理温度的升高而增强,进一步将热处理温度升至1000℃时发光强度又明显降低.发光强度主要受ZnO、MgO纳米晶的粒子尺寸、结晶完善程度,尤其是受两相纳米粒子之间相互作用的影响.同时发现选择合适的甘氨酸与硝酸根离子的摩尔比,对改善样品紫外发光特性也很重要. 相似文献
216.
Nonextensive effects on QCD chiral phase diagram and baryon-number fluctuations within Polyakov-Nambu-Jona-Lasinio model
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In this paper, a version of the Polyakov-Nambu-Jona-Lasinio (PNJL) model based on nonextensive statistical mechanics is presented. This new statistics summarizes all possible factors that violate the assumptions of the Boltzmann-Gibbs (BG) statistics to a dimensionless nonextensivity parameter q. Thus, when q tends to 1, it returns to the BG case. Within the nonextensive PNJL model, we found that as q increases, the location of the critical end point (CEP) exhibits non-monotonic behavior. That is, for \begin{document}$ q<1.15 $\end{document} ![]()
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, CEP moves in the direction of lower temperature and larger quark chemical potential. However, for \begin{document}$ q>1.15 $\end{document} ![]()
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, CEP turns to move in the direction of lower temperature and lower quark chemical potential. In addition, we studied the moments of the net-baryon number distribution, that is, variance (\begin{document}$ \sigma^{2} $\end{document} ![]()
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), skewness (S), and kurtosis (κ). Our results are generally consistent with the latest experimental data reported, especially for \begin{document}$ \sqrt{S_{NN}}>19.6\ \mathrm{GeV} $\end{document} ![]()
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, when q is set to \begin{document}$ 1.07 $\end{document} ![]()
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. 相似文献
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本文给出了一种任意平面域内三角形网格自动生成及自动调整算法,并编制了相应的程序。通过对带U形槽的三点变曲试件的分析,证明本文算法是可行的,并且具有稳定性能好、收敛速度快的优点。 相似文献
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Programmable Engineering of a Biosensing Interface with Tetrahedral DNA Nanostructures for Ultrasensitive DNA Detection
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Meihua Lin Jingjing Wang Guobao Zhou Jianbang Wang Na Wu Prof. Jianxin Lu Prof. Jimin Gao Prof. Xiaoqing Chen Dr. Jiye Shi Prof. Xiaolei Zuo Prof. Chunhai Fan 《Angewandte Chemie (International ed. in English)》2015,54(7):2151-2155
Self‐assembled DNA nanostructures with precise sizes allow a programmable “soft lithography” approach to engineer the interface of electrochemical DNA sensors. By using millimeter‐sized gold electrodes modified with several types of tetrahedral DNA nanostructures (TDNs) of different sizes, both the kinetics and thermodynamics of DNA hybridization were profoundly affected. Because each DNA probe is anchored on an individual TDN, its lateral spacing and interactions are finely tuned by the TDN size. By simply varying the size of the TDNs, the hybridization time was decreased and the hybridization efficiency was increased. More significantly, the detection limit for DNA detection was tuned over four orders of magnitude with differentially nanostructured electrodes, and achieved attomolar sensitivity with polymeric enzyme amplification. 相似文献
220.
One Step Preparation of Reduced Graphene Oxide/Pd–Fe3O4@Polypyrrole Composites and Their Application in Catalysis
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Dr. Tongjie Yao Hao Wang Quan Zuo Dr. Jie Wu Dr. Xiao Zhang Dr. Fang Cui Dr. Tieyu Cui 《化学:亚洲杂志》2015,10(9):1940-1947
The simple preparation of catalysts with superior catalytic activity and good reusability is highly desirable. Herein, we report a novel strategy to construct reduced graphene oxide (rGO)/Pd–Fe3O4@polypyrrole (PPy) catalysts with Pd and Fe3O4 nanoparticles anchored on a rGO nanosheet surface and wrapped in a PPy shell. The synthesis and assembly of both the Pd and Fe3O4 nanoparticles, the preparation of the PPy layer, and the reduction of graphene oxide nanosheets were finished in one step. In the system, the PPy layer not only prevented aggregation of Pd and Fe3O4 nanoparticles, but also generated a synergistic effect with precursor Pd2+ ions, which led to a high dispersity of as‐prepared Pd nanoparticles. Although the procedure was simplified to one step, the catalytic activity and reusability were not sacrificed. In the reduction of 4‐nitrophenol, their catalytic performance was better than that in recent reports. Moreover, the catalysts showed good reusability owing to their magnetic properties. 相似文献