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131.
Host 1 based on the phenolphthalein skeleton and two crown ether moieties demonstrated opposite behaviors toward sodium and potassium cations caused by bidirectional complexation. [reaction: see text] 相似文献
132.
Nakayama T Kurosawa Y Furui S Kerman K Kobayashi M Rao SR Yonezawa Y Nakano K Hino A Yamamura S Takamura Y Tamiya E 《Analytical and bioanalytical chemistry》2006,386(5):1327-1333
Polymerase chain reaction (PCR) is an essential part of research based on genomics or cell analysis. The development of a
microfluidic device that would be suitable for high-temperature-based reactions therefore becomes an important contribution
towards the integration of micro-total analysis systems (μTAS). However, problems associated with the generation of air bubbles
in the microchannels before the introduction of the assay liquid, which we call the “initial start-up” in this study, made
the flow irregular and unstable. In this report, we have tried to address these problems by adapting a novel liquid-flow method
for high-temperature-based reactions. A PDMS-based microfluidic device was fabricated by soft-lithography techniques and placed
on a cartridge heater. The generation of the air bubbles was prevented by introducing the fluorinated oil, an inert and highly
viscous liquid, as the cap just before the introduction of the sample solutions into the microchannels. The technique was
applied for continuous-flow PCR, which could perform PCR on-chip in a microfluidic system. For the evaluation of practical
accuracy, plasmid DNA that serves as a reference molecule for the quantification of genetically modified (GM) maize was used
as the template DNA for continuous-flow PCR. After PCR, the products were collected in a vial and analyzed by gel electrophoresis
to confirm the accuracy of the results. Additionally, quantitative continuous-flow PCR was performed using TaqMan technology
on our PCR device. A laser detection system was also used for the quantitative PCR method. We observed a linear relationship
between the threshold cycle (Ct) and the initial DNA concentration. These results showed that it would be possible to quantify
the initial copies of the template DNA on our microfluidic device. Accurate quantitative DNA analysis in microfluidic systems
is required for the integration of PCR with μTAS, thus we anticipate that our device would have promising potential for applications
in a wide range of research. 相似文献
133.
Ken Takayama Senri Soma Taiji Inoue Hideaki Kakinuma Takashi Haraguchi Kaoru Suzuki 《Applied Physics A: Materials Science & Processing》2010,101(4):727-733
Phosphorus-doped diamond-like carbon (DLC) films were deposited on quartz and p-type silicon (p-Si) substrates by pulsed-laser
deposition. Open-circuit voltage (V
oc) and short-circuit density (I
sc/cm2) from a heating process converted from one type of electrode to another and the two types of electrode pattern are shown
by the V–I characteristics. The first heating process was by a ceramic heater, and the other was by an infrared heater. We adopted two
electrode patterns, from a bipectinate electrode and a plot pattern electrode, to measure electric photovoltaic characteristics.
We were able to upgrade V
oc and I
sc/cm2 to 35∼45 mV, and 0.24 μA/cm2, respectively, under infrared heating. V
oc by the plot pattern electrode was over 2 V under infrared heating and ceramic heating did not match this on deposition by
the PLD method. 相似文献
134.
Ishioka J Liu YH Shimatake K Kurosawa T Ichimura K Toda Y Oda M Tanda S 《Physical review letters》2010,105(17):176401
We discovered the chirality of charge-density waves (CDW) in 1T-TiSe? by using STM and time-domain optical polarimetry. We found that the CDW intensity becomes Ia?∶Ia?∶Ia? = 1∶0.7 ± 0.1∶0.5 ± 0.1, where Ia(i) (i=1,2,3) is the amplitude of the tunneling current contributed by the CDWs. There were two states, in which the three intensity peaks of the CDW decrease clockwise and anticlockwise. The chirality in CDW results in the threefold symmetry breaking. Macroscopically, twofold symmetry was indeed observed in optical measurement. We propose the new generalized CDW chirality H(CDW) ≡ q?·(q?×q?), where q(i) are the CDW q vectors, which is independent of the symmetry of components. The nonzero H(CDW)-the triple-q vectors do not exist in an identical plane in the reciprocal space-should induce a real-space chirality in CDW system. 相似文献
135.
136.
In DEA, there are typically two schemes for measuring efficiency of DMUs; radial and non-radial. Radial models assume proportional change of inputs/outputs and usually remaining slacks are not directly accounted for inefficiency. On the other hand, non-radial models deal with slacks of each input/output individually and independently, and integrate them into an efficiency measure, called slacks-based measure (SBM). In this paper, we point out shortcomings of the SBM and propose four variants of the SBM model. The original SBM model evaluates efficiency of DMUs referring to the furthest frontier point within a range. This results in the hardest score for the objective DMU and the projection may go to a remote point on the efficient frontier which may be inappropriate as the reference. In an effort to overcome this shortcoming, we first investigate frontier (facet) structure of the production possibility set. Then we propose Variation I that evaluates each DMU by the nearest point on the same frontier as the SBM found. However, there exist other potential facets for evaluating DMUs. Therefore we propose Variation II that evaluates each DMU from all facets. We then employ clustering methods to classify DMUs into several groups, and apply Variation II within each cluster. This Variation III gives more reasonable efficiency scores with less effort. Lastly we propose a random search method (Variation IV) for reducing the burden of enumeration of facets. The results are approximate but practical in usage. 相似文献
137.
Takeshi Kurosawa 《Results in Mathematics》2010,57(1-2):1-22
Let ${\Phi_0(\boldmath{z})}$ be the function defined by $$\Phi_0({\boldmath z}) = \Phi _{0}(z_1,\ldots, z_m)=\sum_{k\geq 0}\frac{E_k(z_1^{r^k},\ldots,z_m^{r^k})}{F_k(z_1^{r^k},\ldots,z_m^{r^k})},$$ where ${E_k(\boldmath{z})}$ and ${F_k(\boldmath{z})}$ are polynomials in m variables ${\boldmath{z} = (z_1,\ldots, z_m)}$ with coefficients satisfying a weak growth condition and r ≥ 2 a fixed integer. For an algebraic point ${\boldmath{\alpha}}$ satisfying some conditions, we prove that ${\Phi_{0}(\boldmath{\alpha})}$ is algebraic if and only if ${\Phi_{0}(\boldmath{z})}$ is a rational function. This is a generalization of the transcendence criterion of Duverney and Nishioka in one variable case. As applications, we give some examples of transcendental numbers. 相似文献
138.
We report STM/STS observations on the 4a×4a charge order in the pseudogap (PG) and superconducting (SC) states of Bi2Sr2CaCu2O8+δ, and suggest that the charge order is associated with incoherent quasiparticle or pair states around the antinodal fermi surface (FS), which are also responsible for the PG, and it can coexist with the superconductivity caused by the pairing of coherent quasiparticles on the nodal fermi arc. We also suggest that the nanometer-scale gap inhomogeneity in the SC state, reported previously [Pan, et al., Nature 413 (2001) 282; Mommo, et al., J. Phys. Soc. Jpn. 74 (2005) 2400; Hashimoto, et al., Phys. Rev. B74 (2006) 064508] arises from that in the PG state, which occurs around the antinodal FS. 相似文献
139.
Yasuyuki Tezuka Tatsuroh Ohtsuka Kaoru Adachi Ryota Komiya Noriyoshi Ohno Norimasa Okui 《Macromolecular rapid communications》2008,29(14):1237-1241
A series of size‐controlled, cyclic poly(tetrahydrofuran)s ( of 4 400–8 600) that consist exclusively of the monomer, i.e., oxytetramethylene, unit ( I ) have been prepared in high yield through the metathesis polymer cyclization of a telechelic precursor having allyl groups, 1 , in the presence of a Grubbs catalyst, and the subsequent hydrogenation of the linking, i.e., 2‐butenoxy, unit in the presence of an Adams' catalyst (PtO2). A remarkable topology effect has subsequently been observed upon the isothermal crystallization of these two model polymers, showing distinctive spherulite growth rates and spherulite morphologies in comparison with the relevant linear poly(tetrahydrofuran) counterpart that has ethoxy end groups ( II ).
140.
Feng Cheng Shuqi Wu Wenwei Zheng Shengqun Su Takumi Nakanishi Wenhuang Xu Pritam Sadhukhan Hibiki Sejima Shimon Ikenaga Kaoru Yamamoto Kaige Gao Shinji Kanegawa Prof. Osamu Sato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(59):e202202161
The crystallization of a complex having electron transfer properties in a polar space group can induce the polarization switching of a crystal in a specific direction, which is attractive for the development of sensors, memory devices, and capacitors. Unfortunately, the probability of crystallization in a polar space group is usually low. Noticing that enantiopure compounds crystallize in Sohncke space groups, this paper reports a strategy for the molecular design of non-ferroelectric polarization switching crystals based on the use of intramolecular electron transfer and chirality. In addition, this paper describes the synthesis of a mononuclear valence tautomeric (VT) cobalt complex bearing an enantiopure ligand. The introduction of enantiomer enables the crystallization of the complex in the polar space group (P21). The polarization of the crystals along the b-axis direction is not canceled out and the VT transition is accompanied by a change in the macroscopic polarization of the polar crystal. Polarization switching via electron transfer is realized at around room temperature. 相似文献