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101.
Shingo Ebata Morio Ishihara Kousuke Kumondai Ryo Mibuka Kiichiro Uchino Hisayoshi Yurimoto 《Journal of the American Society for Mass Spectrometry》2013,24(2):222-229
A new system incorporating a multi-turn time-of-flight secondary ion/sputtered neutral mass spectrometer (TOF-SIMS/SNMS) with laser post-ionization was designed and constructed. This system consists of a gallium focused ion beam, femtosecond (fs) laser for post-ionization, and multi-turn TOF mass spectrometer. When laser post-ionization was used, the secondary ion signal strengths for several metals increased by up to 650 times, and were greater than the values obtained in conventional TOF-SIMS experiments. Use of the multi-turn mass spectrometer resulted in an increase in mass resolving power with increase in the total TOF. The mass resolving power reached to 23,000 after 800 multi-turn cycles, corresponding to a flight path length of 1040 m. These results indicated that this system is very effective for the analysis of valuable materials such as space samples with high sensitivity, high mass resolving power, and high lateral resolution. 相似文献
102.
Abstract Polyallylamine and polystyrene beads were allowed to react with 3,5-dibutyl-4-hydroxybenzaldehyde (BHB) and t-butylhydroquinone (BHQ), respectively. The polymeric products, poly-Aa(BHB) and polySt(BHQ) beads worked functionally as antioxidants. The antioxidant effect of the polymer beads in the oxidation of linoleic acid suspensions was investigated by both the ferric thiocyanate and thiobarbituric acid methods. The antioxidant activity of poly-St(BHQ) beads was higher than that of poly-Aa(BHB) ones. It was found that the antioxidant activity for 2 mg of 3, 5-dibutyl-4-hydroxytoluene (BHT) corresponded to that for 11.7 g of poly-Aa(BHB) and that of 0.6 g of poly-St(BHQ). The polymer beads are potential antioxidants for foods since their separation from a food oil after their use is easy because of their insolubility. 相似文献
103.
Trace amounts of cobalt and nickel in a water sample were quantitatively coprecipitated with scandium hydroxide at pH 8.0-10.5. Because the coprecipitant could be easily dissolved with 1 mol dm(-3) nitric acid, and the presence of up to 10 mg cm(-1) of scandium did not interfere with the graphite-furnace atomic absorption spectrometric determination of cobalt and nickel, the volume of the final solution prepared for the determination could be minimized down to 0.5 cm3. The concentration factor was 400-fold and the detection limits (signal to noise = 2) were 5.0 pg cm(-3) of cobalt and 10.0 pg cm(-3) of nickel in 200 cm3 of the initial sample solution. The 27 diverse ions investigated did not interfere with the determination in at least a 500-fold mass ratio to cobalt or nickel. The proposed method was successfully applied to the determination of trace amounts of cobalt and nickel in river-water samples. 相似文献
104.
d-cycloserine (CS) is transformed into cis-3, 6-bis(aminooxymethyl)-2, 5-piperazinedione (CS-dimer) in the solid state under a humid atmosphere. This dimerization process was followed by measuring the IR bands characteristic of CS and CS-dimer. The reaction was accelerated by the presence of increased water vapor. The X-ray analysis of CS monohydrate (CS · H2O) revealed that the CS molecules exist as a zwitter ion where the α-amino N atom is protonated and the amide N atom is deprotonated in the crystal. Participation of water molecules was suggested in the dimerization of CS. 相似文献
105.
Kozawa Takahiro Kondo Akira Fukuyama Kayo Naito Makio Koga Hideyuki Shimo Yusuke Saito Toshiya Iba Hideki Inda Yasushi Oono Tomomi Katoh Takashi Nakajima Kousuke 《Journal of Solid State Electrochemistry》2019,23(4):1297-1302
Journal of Solid State Electrochemistry - All-solid-state Li batteries are suitable for the application of 5 V-class cathode materials that can provide high energy densities. However, it is hard to... 相似文献
106.
Masaaki Motozawa Shota Ishitsuka Kaoru Iwamoto Hirotomo Ando Tetsuya Senda Yasuo Kawaguchi 《Flow, Turbulence and Combustion》2012,88(1-2):121-141
Turbulent drag reducing flow with blowing polymer solution from the channel wall was investigated experimentally using particle image velocimetry (PIV). Experiments were carried out with varying conditions of blowing polymer solution (e.g. weight concentration of polymer solution). Reynolds number based on the channel height and mean velocity was set to 20000 and 40000. When the polymer solution was blown from the channel wall, streamwise velocity fluctuation little increased, but wall-normal velocity fluctuation, Reynolds shear stress and correlation coefficient decreased significantly only near the blower wall. This behavior corresponds to the decrease of the ejection and sweep in the near-wall region observed by the investigation of instantaneous velocity map. On the contrary, this characteristic behavior was not observed at a position away from the blower wall (y/(H/2) > 0.4) and the scatter plot was almost the same as that of the water flow in this region. These results suggest that there are two regions in the drag reducing flow with blowing polymer solution from the wall; one is a non-Newtonian region which exists near the blower wall, and the other is a Newtonian region at a distance from the wall. The non-Newtonian region plays a key role in the drag reduction by the blowing polymer solution. 相似文献
107.
Chao Chen Florian Eweiner Birgit Wibbeling Roland Frhlich Shunsuke Senda Yasuhiro Ohki Kazuyuki Tatsumi Stefan Grimme Gerald Kehr Gerhard Erker 《化学:亚洲杂志》2010,5(10):2199-2208
The zirconocene complex [{(C6F5)2B‐(CH2)3‐Cp}(Cp‐PtBu2)ZrCl2] ( 6 ; Cp=cyclo‐C5H4) was prepared by hydroboration of [(allyl‐Cp)(Cp‐PtBu2)ZrCl2] ( 5 ) with HB(C6F5)2 (“Piers’ borane”). It represents a frustrated Lewis pair (FLP) in which both the Lewis acid and the Lewis base were attached at the metallocene framework. Its reaction with 1‐pentyne did not result in the 1,2‐addition of or deprotonation reaction by the FLP, but rather in the 1,1‐carboboration of the triple bond, thereby obtaining a Z/E mixture (1.2:1) of the respective organometallic substituted alkenes 7 . The analogous reaction of 1‐pentyne with the phosphorous‐free system [{(C6F5)2B‐(CH2)3‐Cp)}CpZrCl2] ( 9 ) gave the respective 1,1‐carboboration products ( Z‐10 / E‐10 ≈1.3:1). 相似文献
108.
109.
Yuki Matsumoto Takafumi Yamamoto Kousuke Nakano Hiroshi Takatsu Taito Murakami Kenta Hongo Ryo Maezono Hiraku Ogino Dongjoon Song Craig M. Brown Cdric Tassel Hiroshi Kageyama 《Angewandte Chemie (International ed. in English)》2019,58(3):756-759
Square‐planar coordinate Ni2+ ions in oxides are exclusively limited to a low‐spin state (S=0) owing to extensive crystal field splitting. Layered oxychalcogenides A2NiIIO2Ag2Se2 (A=Sr, Ba) with the S=1 NiO2 square lattice are now reported. The structural analysis revealed that the Ni2+ ion is under‐bonded by a significant tensile strain from neighboring Ag2Se2 layers, leading to the reduction in crystal field splitting. Ba2NiO2Ag2Se2 exhibits a G‐type spin order at 130 K, indicating fairly strong in‐plane interactions. The high‐pressure synthesis employed here possibly assists the expansion of NiO2 square lattice by taking the advantage of the difference in compressibility in oxide and selenide layers. 相似文献
110.