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141.
本文采用氢化物-非色散原子荧光光谱法研究了十几种饲料矿物添加剂中金属离子对砷测定的干扰,采用加入硫脲-抗坏血酸混合溶液、碘化钾分离、加热蒸干等方法消除干扰。同时本文还对测定砷的酸度、硼氢化钾浓度和仪器工作参数进行了研究和优化。方法相对标准偏差(RSD)为0.54%,检出限(D.L)为54.5ng/L,样品国.加标回收率为102.9%。实际样品测定结果与胂斑法相比具有很好的一致性。 相似文献
142.
根据对应原理,得到了类氢原子能态平均寿命半经典的计算公式τ(n,l),然后利用相对论单通道量子数亏损理论进行推广,得到用来计算考虑总角动量J的激发态寿命公式τ(n,l,l+1/2)和τ(n,l,l-1/2),利用单通道量子数亏损理论得到了碱金属原子n、l远大于1时激发态寿命的半经典公式τ(n.l)=τ0(m+M/nm/v/+M)2v7l(l+1/2)/n4,其计算结果和实验数据符合的很好. 相似文献
143.
M. Drewsen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(1):125-127
We briefly discuss some possibilities for cooling, identification and spectroscopy of super-heavy element (SHE) ions based
on recent results obtained from studies of atomic and molecular ions in linear rf traps. Since these investigations only relied
on the charge and the mass of the ion of interest, we believe it should be straight forward to adopt most of the techniques
for SHE ion research. 相似文献
144.
Hiroshi Aoki Ken Hosoya Tomohisa Norisuye Nobuo Tanaka Daisuke Tokuda Norio Ishizuka Kazuki Nakanishi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(2):949-958
An investigation was made of the gelation of dimethacrylate‐type crosslinking agents in view of an application for separation media. The study mainly centered on a crosslinking agent, glycerol dimethacrylate (GDMA), which is relatively hydrophilic because of a hydroxyl group in the middle of its structure. The gelation of GDMA was compared with that of other hydrophobic crosslinking agents such as ethylene glycol dimethacrylate and 1,6‐hexanediol dimethacrylate. The diluents used in the study were toluene, toluene with methanol, and cyclohexanol. The gelation was observed in real time with a charge coupled device camera and dynamic light scattering (DLS). Also, the separated dry gels were extensively characterized with scanning electron microscopy, BET (N2 absorption and desorption isotherm), and Fourier transform infrared. DLS analysis showed a stronger molecular interaction of GDMA gelation in toluene, whereas this interaction was much weaker in an alcoholic solvent such as toluene with methanol or cyclohexanol. This indicated that GDMA gelation might proceed through hydrogen bonding as well as a crosslinking reaction of vinyl groups. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 949–958, 2006 相似文献
145.
Tzong‐Ming Wu Shih‐Hsiang Lin 《Journal of polymer science. Part A, Polymer chemistry》2006,44(21):6449-6457
Size‐controllable polypyrrole (PPy)/multiwalled carbon nanotube (MWCNT) composites have been synthesized by in situ chemical oxidation polymerization directed by various concentrations of cationic surfactant cetyltrimethylammonium bromide (CTAB). Raman spectra, FTIR, SEM, and TEM were used to characterize their structure and morphology. These results showed that the composites are core (MWCNT)–shell (PPy) tubular structures with the thickness of the PPy layer in the range of 20–40 nm, depending on the concentration of CTAB. Raman and FTIR spectra of the composites are almost identical to those of PPy alone. The electrical conductivities of these composites are 1–2 orders of magnitude higher than those of PPy without MWCNTs. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6449–6457, 2006 相似文献
146.
Ken‐ichi Shinohara Tasuku Suzuki Takeshi Kitami Shingo Yamaguchi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(2):801-809
We fabricated a micrometer‐long supramolecular chain in which π‐conjugated polyrotaxane was coupled. A new experimental setup was designed and constructed, and the simultaneous direct imaging of the structure and fluorescent function was achieved. Furthermore, we identified the formation of a polymer intertwined network and observed novel fluorescence due to a long‐range interaction via this intertwined network over a distance of 5 μm or more without quenching over 15 min in the near field. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 801–809, 2006 相似文献
147.
148.
Wolfgang H. Binder Laura Petraru Robert Sachenshofer Ronald Zirbs 《Monatshefte für Chemie / Chemical Monthly》2006,137(7):835-841
Summary. The surface modification of nanoparticles via azide/alkine-1,3-dipolar cycloaddition-reactions is described. Ligand exchange onto various nanoparticles was monitored by
1H NMR spectroscopy and formed the basis for the attachment of ligands onto the nanoparticles and their subsequent modification
by dipolar cycloaddition reactions. Nanoparticle-surfaces were monitored by binding onto self-assembled monolayers derivatized
with matching supramolecular interactions after derivatization. 相似文献
149.
The new research reactor FRM-II near Munich has a strong positron source, which delivers an intense, nearly monoenergetic positron beam. Our positron systems, the pulsed low energy positron source (PLEPS) and the scanning positron microscope (SPM) will be operated at this beam. Some aspects of matching these systems to the new positron source will be discussed.Considerable improvements are expected, e.g. more than 105 s−1 recorded events at PLEPS and sub-micrometre resolution at SPM. They will enable investigations in so far inaccessible problems like the evaluation of annihilation characteristics and trapping constants of individual defects or studies of fast dynamical processes. In applied materials science complex defect structures will be studied which demand a resolution into many differing lifetimes, e.g. fractured specimens, wear, corrosion, etc. Also large series of measurements at small systematic modifications are planned. There is also the opportunity to analyse in addition the chemical microstructure of the specimens by means of a hydrogen microprobe and other ion beam techniques available close to FRM-II at the Technical University of Munich. 相似文献
150.
Anisha Gokarna Yong Hwan Kim Yong-Hoon Cho Min Su Lee In Cheol Kang Hyun Kyu Park Min Gon Kim Bong Hyun Chung 《Optical Review》2006,13(4):288-291
We demonstrate the fluorescence mapping of protein microarrays by the technique of scanning near-field optical microscopy
(SNOM) and confocal microscopy. Micron sized spots (300 μm) of human Immunoglobulin G (hIgG) protein with and without a Cy3
dye labeling have been fabricated on glass substrates by an immobilization method which makes use of calixcrown derivatives
termed Prolinker. We have also tried to probe into the well-known “doughnut effect” observed in fluorescence images of proteins
using the SNOM technique. The topographic and fluorescence SNOM images revealed that the number of proteins at the boundary
of the spot were more than at the center in the case of the microarray spot which showed brighter luminescence at the edge
than at the center in the confocal image. 相似文献