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排序方式: 共有208条查询结果,搜索用时 15 毫秒
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Peng An Fang Zuo Yuan Peng Wu Jun Hua Zhang Zhao Hui Zheng Xiao Bin Ding Yu Xing Peng 《中国化学快报》2012,23(9):1099-1102
A fast approach was described for the synthesis of water-dispersible monodisperse dopamine-coated Fe3O4 nanoparticles(DA-Fe3O4) with uniform size and shape via ligand-exchange of oleic acid on Fe3O4 using only 2 min.The prepared DA-Fe3O4 nanoparticles were characterized by transmission electron microscopy,Fourier transform infrared spectrometry,and vibrating sample magnetometer.The results indicated that the resulting DA-Fe3O4 nanoparticles had an average diameter of about 19.2 nm. The magnetic saturation value of the prepared DA-Fe3O4 nanoparticles was determined to be 72.87 emu/g,which indicating a well-established superparamagnetic property. 相似文献
3.
Daisuke KOZAKI Nobutake NAKATANI Masanobu MORI Nobukazu NAKAGOSHI Kazuhiko TANAKA 《色谱》2012,30(7):721-727
A unified ion-exclusion chromatography(IEC) system for monitoring anionic and cationic nutrients like NH + 4,NO 2,NO 3,phosphate ion,silicate ion and HCO 3 was developed and applied to several environmental waters.The IEC system consisted of four IEC methodologies,including the IEC with ultraviolet(UV) detection at 210 nm for determining NH + 4 on anion-exchange separation column in OH form connected with anion-exchange UV-conversion column in I form in tandem,the IEC with UV-detection at 210 nm for determining simultaneously NO 2 and NO 3 on cation-exchange separation column in H + form,the IEC with UV-detection at 210 nm for determining HCO 3 on cation-exchange separation column in H + form connected with anion-exchange UV-conversion column in I form in tandem,and the IEC with visible-detection based on molybdenum-blue reaction for determining simultaneously silicate and phosphate ions on cation-exchange separation column in H + form.These IEC systems were combined through three manually-driven 6-port column selection valves to select each separation column to determine selectively the ionic nutrients.Using this sequential water quality monitoring system,the analytical performances such as calibration linearity,reproducibility,detection limit and recovery were also tested under the optimized chromatographic conditions.This novel water quality monitoring system has been applied successfully for the determination of the ionic eutrophication components in sub-urban river waters. 相似文献
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HAN Tao LU XiaoChun WANG Xue RAO YongNan ZOU DeCai YANG JianFei & WU YangYang National Time Service Center Xi'an China Key Laboratory of Precision Navigation Timing Technology Chinese Academy of Sciences Graduate University of the Chinese Academy of Sciences Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the interoperability with the existing ones necessitates the study of the assessment algorithm of this idea.In this paper,an assessment algorithm for interoperability comprehensive benefits based on the differential equation dynamical system is discussed.There are two important aspects in GNSS tha... 相似文献
6.
CHEN Liang ZHOU XiaoHong ZHANG YuHu ZHANG ShuangQuan & ZHU LiHua Institute of Modern Physics Chinese Academy of Sciences Lanzhou China Graduate University of Chinese Academy of Sciences Beijing State Key Laboratory of Nuclear Physics Technology School of Physics Peking University Beijing China Institute of Atomic Energy Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(Z1)
High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated wit... 相似文献
7.
Parametric X-ray Radiation (PXR) can be used as a novel, quasi-monochromatic energy-tunable and high-yield X-ray source. It is produced at the Bragg angle by a relativistic electron beam passing through the periodic structure of crystal materials. This article concerns the PXR experiment using low energy electrons (10 MeV) from NCEL (Novel Compact Electron-Linac). The difficulty of the experiment is to distinguish the PXR photons form the background. The design of the experiment relies mainly on the yield of PXR, the Bremsstrahlung background of the X-rays and the capability of the detector. 相似文献
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NING Zhao-lun DING Jin-ying JIN Ri-zhe KANG Chuan-qing CHENG Yan-qin GAO Lian-xun . State Key Laboratory of Polymer Physics Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun P. R. China . Graduate School of Chinese Academy of Sciences Beijing 《高等学校化学研究》2011,27(1):45-48
A number of salen-metal complexes were prepared and their enantioselective catalytic properties toward the asymmetric iodolactonization of (E)-and (Z)-5-substituted-4-pentenoic acid derivatives were investigated. The catalyst system based on salen-Co(II) complex exhibited moderate to good enantioselectivity with the e.e. value ranging from 53% to 74%, as well as high regioselectivity of δ-vs. γ-iodolactones. The salen-Co(II) complex showed the highest enantioselectivity on the asymmetric iodolactonizations ... 相似文献
10.
WANG Jin-e WANG Cheng-ke LIU Dian-jun WANG Zhen-xin . State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun P. R. China . Graduate School of Chinese Academy of Sciences Beijing 《高等学校化学研究》2011,(2):193-197
The interactions of antibiotic with living cells were studied by lectin conjugated gold nanoparticles(GNPs) based colorimetric assay. Because of the high affinity of lectin for saccharides, the lectin conjugated GNPs are able to employ as indicators for monitoring the antibiotic induced changes of glycosyl complexes. The interactions of a well known antibiotic, tunicamycin, with two different cell lines, HeLa and SHG-44, were selected to establish this assay. In the presence of tunicamycin, the dose- and ti... 相似文献