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71.
Toshihide Ibaraki 《Discrete Applied Mathematics》1980,2(2):155-158
It is known that a minimization problem having a finite feasible region with k elements can be formulated as an integer programming problem by introducing at most [log2k] additional integer variables. In this note, we show that this bound is best possible in the sense that some minimization problem actually requires [log2k] additional variables. 相似文献
72.
Minji Jin Yu Nagaoka Kazuomi Nishi Kinuyo Ogawa Shoji Nagahata Toshihide Horikawa Masahiro Katoh Tahei Tomida Jun’ichi Hayashi 《Adsorption》2008,14(2-3):257-263
Photocatalysts of TiO2 and La-doped TiO2 were prepared by calcining the pure TiO2 sols and the sols mixed with La(NO3)3⋅6H2O at 873 K, respectively. These photocatalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy
(XPS), scanning electron microscopy (SEM) and N2 adsorption-desorption isotherms measurement. As results, the BET surface area, pore diameter, mesopore volume and micropore
volume slightly increased, while the crystallite size and the phase structure were little affected by lanthanum doping. The
equilibrium adsorption of methylene blue (MB) on the photocatalysts were measured in a dark room. The adsorption isotherms
were confirmed to fit to the Langmuir theory. Photocatalytic activities of the photocatalysts were studied by employing the
photocatalytic degradation of MB in water and degradation of acetaldehyde in air under UV-irradiation using a black light.
Kinetic analysis revealed that the rate controlling steps could be the surface reaction of the adsorbed MB on the catalyst
surface for MB degradation and the reaction of adsorbed acetaldehyde with the gaseous acetaldehyde for degradation of acetaldehyde,
respectively. 相似文献
73.
CO2是最重要的可再生碳源之一.为了将CO2转化为有用的有机化合物,我们研究了二种模型硅基"废"材料—乙硅烷和硅粉的反应活性.在这些反应中,氟盐的催化活性最高,在常压、在质子源水和硅基还原剂的存在下,CO2可转化为甲酸.原位NMR和动力学分析表明,含氢硅烷和五配位的硅物种分别是反应中间物和活性物种. 相似文献
74.
We describe a method of constructing a new kind of splines with compact support on . These basis functions consisting of a linear combination of the cardinal B-splines of mixed orders enable us to achieve
simultaneously a good sampling approximation and an interpolation of any smooth function. 相似文献
75.
Guanidine-containing molecular transporters: sorbitol-based transporters show high intracellular selectivity toward mitochondria 总被引:1,自引:0,他引:1
76.
Endre Boros Yves Crama Peter L. Hammer Toshihide Ibaraki Alexander Kogan Kazuhisa Makino 《Annals of Operations Research》2011,188(1):33-61
Learning from examples is a frequently arising challenge, with a large number of algorithms proposed in the classification,
data mining and machine learning literature. The evaluation of the quality of such algorithms is frequently carried out ex post, on an experimental basis: their performance is measured either by cross validation on benchmark data sets, or by clinical
trials. Few of these approaches evaluate the learning process ex ante, on its own merits. In this paper, we discuss a property of rule-based classifiers which we call “justifiability”, and which
focuses on the type of information extracted from the given training set in order to classify new observations. We investigate
some interesting mathematical properties of justifiable classifiers. In particular, we establish the existence of justifiable
classifiers, and we show that several well-known learning approaches, such as decision trees or nearest neighbor based methods,
automatically provide justifiable classifiers. We also identify maximal subsets of observations which must be classified in
the same way by every justifiable classifiers. Finally, we illustrate by a numerical example that using classifiers based
on “most justifiable” rules does not seem to lead to overfitting, even though it involves an element of optimization. 相似文献
77.
Kazuhiro Kobayashi Toshihide Komatsu Yuki Yokoi Hisatoshi Konishi 《Helvetica chimica acta》2011,94(1):67-72
An efficient synthesis of 3‐alkyl‐3,4‐dihydro‐4‐thioxobenzoquinazolin‐2(1H)‐ones 3 has been accomplished in two steps and in satisfactory yields from 1‐bromo‐2‐fluorobenzenes 1 . Thus, the reaction of 1‐fluoro‐2‐lithiobenzenes, generated by the Br/Li exchange between 1 and BuLi, with alkyl isothiocyanates, gives N‐alkyl‐2‐fluorobenzothioamides 2 , which, in turn, react with a series of isocyanates in the presence of NaH to give the desired products 3 . 相似文献
78.
Masao Tamada Yuji Ueki Noriaki Seko Toshihide Takeda Shin-ichi Kawano 《Radiation Physics and Chemistry》2012,81(8):971-974
High performance adsorbent is expected to be synthesized for the removal of Ni and Cu ions from strong alkaline solution used in the surface etching process of Si wafer. Fibrous adsorbent was synthesized by radiation-induce emulsion graft polymerization onto polyethylene nonwoven fabric and subsequent amination. The reaction condition was optimized using 30 L reaction vessel and nonwoven fabric, 0.3 m width and 18 m long. The resulting fibrous adsorbent was evaluated by 48 wt% NaOH and KOH contaminated with Ni and Cu ions, respectively. The concentration levels of Ni and Cu ions was reduced to less than 1 μg/kg (ppb) at the flow rate of 10 h?1 in space velocity. The life of adsorbent was 30 times higher than that of the commercialized resin. This novel adsorbent was commercialized as METOLATE® since the ability of adsorption is remarkably higher than that of commercial resin used practically in Si wafer processing. 相似文献
79.
Mikio Koyano Hirokazu Watanabe Yasuhisa Yamamura Toshihide Tsuji Shin'ichi Katayama 《Molecular Crystals and Liquid Crystals》2013,570(2):33-38
Abstract Raman scattering spectra and magnetic susceptibility are measured in intercalation compounds FexNbS2 (0.159≤x≤0.325). A strong modification of Raman spectra is observed in a sample with x=0.239 (~ 0.25) which is accompanied by 2a × 2a structural change and antiferromagnetic ordering. Some correlations between magnetic ordering (antiferromagnetic or spin glass) and structural change are also discussed for wide range of Fe contents x. 相似文献
80.
Emiko Kinoshita‐Kikuta Hiroshi Kusamoto Syogo Ono Keisuke Akayama Yoko Eguchi Masayuki Igarashi Toshihide Okajima Ryutaro Utsumi Eiji Kinoshita Tohru Koike 《Electrophoresis》2019,40(22):3005-3013
In the bacterial signaling mechanisms known as two‐component systems (TCSs), signals are generally conveyed by means of a His–Asp phosphorelay. Each system consists of a histidine kinase (HK) and its cognate response regulator. Because of the labile nature of phosphorylated His and Asp residues, few approaches are available that permit a quantitative analysis of their phosphorylation status. Here, we show that the Phos‐tag dye technology is suitable for the fluorescent detection of His‐ and Asp‐phosphorylated proteins separated by SDS‐PAGE. The dynamics of the His–Asp phosphorelay of recombinant EnvZ‐OmpR, a TCS derived from Escherichia coli, were examined by SDS‐PAGE followed by simple rapid staining with Phos‐tag Magenta fluorescent dye. The technique permitted not only the quantitative monitoring of the autophosphorylation reactions of EnvZ and OmpR in the presence of adenosine triphosphate (ATP) or acetyl phosphate, respectively, but also that of the phosphotransfer reaction from EnvZ to OmpR, which occurs within 1 min in the presence of ATP. Furthermore, we demonstrate profiling of waldiomycin, an HK inhibitor, by using the Phos‐tag Cyan gel staining. We believe that the Phos‐tag dye technology provides a simple and convenient fluorometric approach for screening of HK inhibitors that have potential as new antimicrobial agents. 相似文献