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31.
32.
A novel method for determination of inorganic oxyanions by electrospray ionization mass spectrometry using dehydration reactions
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Hirochika Kojima Shota Kurihara Yoshito Watanabe Koki Iwamaru Kiichi Sato Kin‐ichi Tsunoda Hiroki Hotta 《Journal of mass spectrometry : JMS》2016,51(2):123-131
Novel methods for the determination of inorganic oxyanions by electrospray (ES) ionization mass spectrometry have been developed using dehydration reactions between oxyanions and carboxylic acids at the ES interface. Twelve oxyanions (VO3?, CrO42?, MoO42?, WO42?, BO33?, SiO32?, SiO44?, AsO44?, AsO2?, SeO42?, SeO32? and NO2?), out of 16 tested, reacted with at least one of four aminopolycarboxylic acids, i.e. iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), trans‐1,2‐diaminocyclohexane‐N,N,N′,N′‐tetraacetic acid and triethylenetetramine‐N,N,N′,N″,N′″,N′″‐hexaacetic acid, at the ES interface to produce the dehydration products that gave intense mass ion responses, sufficient for trace analysis. As examples, trace determinations of CrVI and silica in water samples were achieved after online ion exchange chromatography, where the dehydration product of CrO42? and NTA (m/z 290) and that of SiO44? and IDA (m/z 192) were measured. The limits of detection of the respective methods were 17 nM (0.83 ng Cr/ml) for CrVI and 0.17 μM (4.8 ng Si/mL) for SiO44?. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
33.
Murrae J. Bowden Antoni S. Gozdz Joseph M. DeSimone James E. McGrath Seiki Ito Minoru Matsuda 《Macromolecular Symposia》1992,53(1):125-137
The various chemical approaches aimed at improving the reactive-ion etch resistance of poly(olefin sulfone)s are described. Resist systems based on incorporation of RIE-resistant moieties via random copolymerization, blending and block copolymer formation are described and lithographic properties noted. 相似文献
34.
Removal of phosphate by aluminum oxide hydroxide 总被引:17,自引:0,他引:17
Tanada S Kabayama M Kawasaki N Sakiyama T Nakamura T Araki M Tamura T 《Journal of colloid and interface science》2003,257(1):135-140
The development and manufacture of an adsorbent to remove phosphate ion for the prevention of eutrophication in lakes are very important. The characteristics of phosphate adsorption onto aluminum oxide hydroxide were investigated to estimate the adsorption isotherms, the rate of adsorption, and the selectivity of adsorption. Phosphate was easily adsorbed onto aluminum oxide hydroxide, because of the hydroxyl groups. The adsorption of phosphate onto aluminum oxide hydroxide was influenced by pH in solution: the amount adsorbed was greatest at pH 4, ranging with pH from 2 to 9. The optimum pH for phosphate removal by aluminum oxide hydroxide is 4. The selectivity of phosphate adsorption onto aluminum oxide hydroxide was evaluated based on the amount of phosphate ion adsorbed onto aluminum oxide hydroxide from several anion complex solutions. It is phosphate that aluminum oxide hydroxide can selectively adsorb. The selectivity of phosphate onto aluminum oxide hydroxide was about 7000 times that of chloride. This result indicated that the hydroxyl groups on aluminum oxide hydroxide have selective adsorptivity for phosphate and could be used for the removal of phosphate from seawater. 相似文献
35.
Kubo K Akemoto M Anderson S Aoki T Araki S Bane KL Blum P Corlett J Dobashi K Emma P Frisch J Fukuda M Guo Z Hasegawa K Hayano H Higo T Higurashi A Honda Y Iimura T Imai T Jobe K Kamada S Karataev P Kashiwagi S Kim E Kobuki T Kotseroglou T Kurihara Y Kuriki M Kuroda R Kuroda S Lee T Luo X McCormick DJ McKee B Mimashi T Minty M Muto T Naito T Naumenko G Nelson J Nguyen MN Oide K Okugi T Omori T Oshima T Pei G Potylitsyn A Qin Q Raubenheimer T Ross M Sakai H Sakai I Schmidt F Slaton T Smith H 《Physical review letters》2002,88(19):194801
Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance. 相似文献
36.
Although the Hall coefficient R(H) is an informative transport property of metals and semiconductors, its meaning in the cuprate superconductors has been ambiguous because of its unusual characteristics. Here we show that a systematic study of R(H) in La2-xSrxCuO4 single crystals over a wide doping range establishes a qualitative understanding of its peculiar evolution, which turns out to reflect a two-component nature of the electronic structure caused by an unusual development of the Fermi surface recently uncovered by photoemission experiments. 相似文献
37.
Magnetic-field-induced ordering of electrons around vortices is a striking phenomenon recently found in high-T(c) cuprates. To identify its consequence in the quasiparticle dynamics, the magnetic-field (H) dependence of the low-temperature thermal conductivity kappa of La(2-x)SrxCuO4 crystals is studied for a wide doping range. It is found that the behavior of kappa(H) in the subkelvin region changes drastically across optimum doping, and the data for underdoped samples are indicative of unusual magnetic-field-induced localization of quasiparticles; this localization phenomenon is probably responsible for the unusual "insulating normal state" under high magnetic fields. 相似文献
38.
Mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1), obtained from the reaction of N-acyl-N-alkylglycines (2) with trifluoroacetic anhydride, react with ammonia to give 4-trifluoromethyl-3,4-dihydroimidazoles (3) in high yields. Dehydration of 3 gives 4-trifluoromethylimidazoles (4) in high yields. The novel ring transformation of 1 into 3 occurs via a regioselective attack of ammonia on the C-2 position of the ring. 相似文献
39.
Shigeru Odaka Yoshimasa Kurihara 《The European Physical Journal C - Particles and Fields》2007,51(4):867-873
We are developing a consistent method to combine tree-level event generators for hadron collision interactions with those
including one additional QCD radiation from the initial-state partons, based on the limited leading-log (LLL) subtraction
method, aiming at an application to NLO event generators. In this method, a boundary between non-radiative and radiative processes
necessarily appears at the factorization scale (μF). The radiation effects are simulated using a parton shower (PS) in non-radiative processes. It is therefore crucial in our
method to apply a PS which well reproduces the radiation activities evaluated from the matrix-element (ME) calculations for
radiative processes. The PS activity depends on the applied kinematics model. In this paper we introduce two models for our
simple initial-state leading-log PS: a model similar to the ’old’ PYTHIA-PS and a pT-prefixed model motivated by ME calculations. PS simulations employing these models are tested using W-boson production at
LHC as an example. Both simulations show a smooth matching to the LLL subtracted W+1 jet simulation in the pT distribution of W bosons, and the summed pT spectra are stable against a variation of μF, despite that the pT-prefixed PS results in an apparently harder pT spectrum. 相似文献
40.