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1.
Recently, we developed a convenient microfluidic droplet generation device based on vacuum‐driven fluid manipulation with a piezoelectric diaphragm micropump. In the present study built on our previous work, we investigate the influence of settings applied to the piezoelectric pump, such as peak‐to‐peak drive voltage (Vp‐p) and wave frequency, on droplet generation characteristics. Stepwise adjustments to the drive voltage in ±10‐Vp‐p increments over the range of 200?250 Vp‐p during droplet creation revealed that the droplet generation rate could be reproducibly controlled at a specific drive voltage. The droplet generation rate switched within <0.5 s after the input of a new voltage. Although the droplet generation rate depended on the drive voltage, this setting had almost no influence on droplet size. The frequency over the selected range (50?60 Hz) did not markedly influence the droplet generation rate or droplet size. We show that the current fluid manipulation system can be conveniently used for both droplet generation and for rapid droplet reading, which is required in many microfluidic‐based applications. 相似文献
2.
A flow-injection system for the determination of 3-hydroxybutyrate in serum is described. 3-Hydroxybutyrate dehydrogenase is immobilized on poly(vinyl alcohol) beads and incorporated in a flow-injection system. 1-Methoxy-5-methylphenazinium methylsulphate reacts with enzymatically generated NADH to give H2O2, which is detected chemiluminometrically with the reaction of luminol and hexacynoferrate(III). Serum is diluted and filtered through an ultrafiltration membrane. The system responds linearly to injected samples (80 μl) in the concentration range 0.5–300 μM; the detection limit is 0.1 μM. The within-day relative standard deviation (n = 90) for 58 μM 3-hydroxybutyrate in serum is 0.8%. The maximum throughout is 20 samples per hour. The immobilized enzyme is stable for at least 1 month. 相似文献
3.
方永得 张玉虎 M.Oshima Y.Toh 周小红 M.Koizumi A.Osa A.Kimura Y.Hatsukawa T.Morikawa M.Nakamura M.Sugawara H.Kusakari 《中国物理 C》2006,30(2):99-104
利用在束γ谱学实验技术, 通过173Yb(19F,4nγ)反应
布居了188Au的高自旋态, 并对其准粒子带结构进行了研究. 基于实验测量结果, 对原有的双奇核188Au能级纲图做了较大的修改. 通过系统性比较, 对15+以上的能级结构进行了讨论. 相似文献
4.
5.
H. Ohta M. Kimata K. Koyama Y. Oshima M. Motokawa H. Nishikawa K. Kikuchi I. Ikemoto 《International Journal of Infrared and Millimeter Waves》2005,26(11):1525-1530
We have developed a new magneto-optical measurement system using a rotational cavity system equipped with a millimeter vector
network analyzer and a 14 T solenoid type super conducting magnet. The measurement can be performed in the transmission configuration
down to 1.6 K. The results of the precise angular dependence measurement of quasi-one-dimensional organic conductor (DMET)2I3 using the new system are shown, and its Fermi surface will be discussed in connection with the previous reports. 相似文献
6.
K. M. A. Salam Hidekazu Konishi Masahiro Mizuno Hisashi Fukuda Shigeru Nomura 《Applied Surface Science》2002,190(1-4):88-95
Polycrystalline (1−x)Ta2O5−xTiO2 thin films were formed on Si by metalorganic decomposition (MOD) and annealed at various temperatures. As-deposited films were in the amorphous state and were completely transformed to crystalline after annealing above 600 °C. During crystallization, a thin interfacial SiO2 layer was formed at the (1−x)Ta2O5−xTiO2/Si interface. Thin films with 0.92Ta2O5–0.08TiO2 composition exhibited superior insulating properties. The measured dielectric constant and dissipation factor at 1 MHz were 9 and 0.015, respectively, for films annealed at 900 °C. The interface trap density was 2.5×1011 cm−2 eV−1, and flatband voltage was −0.38 V. A charge storage density of 22.8 fC/μm2 was obtained at an applied electric field of 3 MV/cm. The leakage current density was lower than 4×10−9 A/cm2 up to an applied electric field of 6 MV/cm. 相似文献
7.
T.R. Saitoh N. Hashimoto G. Sletten R.A. Bark S. Törmänen M. Bergström K. Furuno K. Furutaka G.B. Hagemann T. Hayakawa T. Komatsubara A. Maj S. Mitarai M. Oshima J. Sampson T. Shizuma P.G. Varmette 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):197-199
High-spin states in 181Ta have been studied via the 176Yb(11B,α2n) reaction at 52 MeV using the PEX array and at 57 MeV using the NORDBALL array, with α-particle detection. The previously
known, Kπ=(7/2)+ ground state band and Kπ=(9/2)− band have been extended to spins (29/2)+ and (31/2)−, respectively. Two new one-quasiparticle bands, the Kπ=(5/2)+ band built on the known (5/2)+ isomer and a Kπ=((1/2)−) band have been observed. Two other rotational bands with three-quasiparticle structure, Kπ=(15/2)− and ((19/2)+ with π(7/2)[404]ν2(1/2)[510](9/2)[624] and π(9/2)[514]ν2(1/2)[510](9/2)[624] configurations, respectively, have been newly observed. The half-life of the Kπ=((19/2)+) bandhead which decays to the head of the (15/2)− band has been measured to be 140(36) ns. However, transitions from the ((19/2)+) state to the (15/2)− band have not been observed.
Received: 26 August 1998 相似文献
8.
9.
A highly sensitive fluorescence quenching method for the determination of silicate based on the formation of an ion associate between molybdosilicate and Rhodamine B (RB) in nitric acid medium was developed. A flow injection system coupled with a fluorescence detector was used for the measurement of fluorescence intensity at 560 and 580 nm as excitation and emission wavelengths, respectively. The calibration graph for Si showed a linear range of 0.1–5 ng cm−3 with correlation coefficient of 0.9999, and the detection limit of 0.06 ng cm−3. The proposed method was successfully applied to the determination of silicate in ultrapurified water with satisfactory results. 相似文献
10.
Hiroki Tomioka Kazuhiko Takai Koichiro Oshima Hitosi Nozaki Koshiro Toriumi 《Tetrahedron letters》1980,21(50):4843-4846
The title complex oxidizes primary and secondary alcohols to the corresponding carbonyl compounds. Stereoselective epoxidation of allylic alcohols is also described. 相似文献