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801.
Hideki Katagiri Masatoshi SakawaKosuke Kato Ichiro Nishizaki 《European Journal of Operational Research》2008
This paper considers multiobjective linear programming problems with fuzzy random variables coefficients. A new decision making model is proposed to maximize both possibility and probability, which is based on possibilistic programming and stochastic programming. An interactive algorithm is constructed to obtain a satisficing solution satisfying at least weak Pareto optimality. 相似文献
802.
We construct certain raising operators of row type for Macdonald's symmetric polynomials by an interpolation method. 相似文献
803.
Qizhao Li Masatoshi Ishida Hiroto Kai Tingting Gu Chengjie Li Xin Li Glib Baryshnikov Xu Liang Weihua Zhu Hans gren Hiroyuki Furuta Yongshu Xie 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(18):5986-5990
A hybrid thia‐norhexaphyrin comprising a directly linked N‐confused pyrrole and thiophene unit ( 1 ) revealed unique macrocycle transformations to afford multiply inner‐annulated aromatic macrocycles. Oxidation with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone triggered a cleavage of the C?S bond of the thiophene unit, accompanied with skeletal rearrangement to afford unique π‐conjugated products: a thiopyrrolo‐pentaphyrin embedded with a pyrrolo[1,2]isothiazole ( 2 ), a sulfur‐free pentaphyrin incorporating an indolizine moiety ( 3 ), and a thiopyranyltriphyrinoid containing a 2H‐thiopyran unit ( 4 ). Furthermore, 2 underwent desulfurization reactions to afford a fused pentaphyrin containing a pyrrolizine moiety ( 5 ) under mild conditions. Using expanded porphyrin scaffolds, oxidative thiophene cleavage and desulfurization of the hitherto unknown N‐confused core‐modified macrocycles would be a practical approach for developing unique polypyrrolic aromatic macrocycles. 相似文献
804.
This paper presents the theoretical basis for both static and dynamic numerical approaches to the elastic stability and elasto-plastic stability of a folding multi-layered truss. Both analyses are based on bifurcation theory and include geometrical non-linearity. The dynamic analysis includes an allowance for contact between nodes. Comparisons are made between elastic behaviour and elasto-plastic behaviour obtained from both numerical dynamic methods in which bifurcations are demonstrated as a theoretically elastic analysis. Our analysis reveals that several folding behaviours in the pantographic truss are identified during the elastic and elasto-plastic instabilities, where the folding behaviour of the truss is shown to be a function of the initial geometry and velocity of the dynamic loading. The authors suggest that understanding this behaviour will be very useful for developing light-weight structures subject to dynamic loading based on static bifurcation analysis and dynamic analysis. 相似文献
805.
Noboru Ohtani Masakazu Katsuno Takashi Aigo Tatsuo Fujimoto Hiroshi Tsuge Hirokatsu Yashiro Masatoshi Kanaya 《Journal of Crystal Growth》2000,210(4):613-622
Surface topography of the {0 0 0 1} facet plane of as-grown 6H- and 4H-SiC crystals was studied ex situ by Nomarski optical microscopy (NOM) and atomic force microscopy (AFM). The surface polarity and the polytype of grown crystals largely affect the growth surface morphology of SiC{0 0 0 1} via differences in several thermodynamic and kinetic parameters. NOM observations revealed giant steps of a few micrometers in height on the {0 0 0 1} growth facet, and it was found that a morphological transition of the growth facet occurred when the growth conditions were changed. AFM imaging of the stepped structure of SiC{0 0 0 1} detected steps of height equal to the unit c-lattice parameter (c=1.512 nm for 6H-SiC and 1.005 nm for 4H-SiC). They are fairly straight and very regularly arranged, giving rise to equidistant step trains. Upon nitrogen doping, these regular step trains on the 6H-SiC(0 0 0
)C and 4H-SiC(0 0 0
)C surfaces became unstable: the equidistant step trains were transformed into meandering macrosteps of height greater than 10 nm. In this paper, we discuss the mechanism of macrostep formation (step bunching) on the SiC{0 0 0 1} surfaces through the consideration of the interplay between step energetics (repulsive step interaction) and kinetics (asymmetric step kinetics) on the growing crystal surface and elucidate how they affect the growth surface morphology of the SiC{0 0 0 1} facet. 相似文献
806.
Three water-soluble arsenic compounds were isolated from the green seaweed Codium fragile. These compounds were identified as 1-glycerophosphoryl-2-hydroxy-3-[5′-deoxy-5′-(dimethylarsinoyl)-β-ribofuranosyloxy]propane (1a), 1′ -(1,2-dihydroxypropyl)-5′ -deoxy-5′ -(dimethylarsinoyl)-β-ribofuranoside (1b), and dimethylarsinic acid ((CH3)2AsOOH). The structures of these compounds were ascertained by 1H NMR spectroscopy. Compounds 1a and 1b accounted for 60 % and dimethylarsinic acid for 5% of the water-soluble arsenic. 相似文献
807.
808.
Zusammenfassung Eine neue Harztüpfelmethode mit Bathocuproindisulfonat zum spezifischen Nachweis von ng Kupfer(II) wird vorgeschlagen. Bei Anwendung eines Kügelchens weißer, weitmaschiger, stark basischer Anionenaustauscher, Diaion PA-Harze, beträgt die Erfassungsgrenze 10,4 ng Kupfer in 10l Probelösung (1:1 · 106).
Vorgetragen vor der 18. Hauptversammlung der japanischen Gesellschaft für analytische Chemie, Sapporo, 2. Oktober 1969. Vortrag Nr. 2D15. 相似文献
Micro analysis with the aid of ion exchanger resins. XXVI
Summary A new resin spot test with bathocuproine disulfonate for the specific detection of ng amounts of copper(II) is described. Using 1 grain of white strongly basic popcorn-resin, Diaion PA 3-series, the identification limit for copper is 10.4 ng in 10l solution (1:1 · 106).
Vorgetragen vor der 18. Hauptversammlung der japanischen Gesellschaft für analytische Chemie, Sapporo, 2. Oktober 1969. Vortrag Nr. 2D15. 相似文献
809.
Molenkamp WC Watanabe M Miyata H Tolbert SH 《Journal of the American Chemical Society》2004,126(14):4476-4477
In this Communication, we show that nanometer scale control of semiconducting polymer chain conformation is possible using host/guest chemistry in highly ordered and macroscopically oriented thin films of mesoporous silica. This control leads to a thin film composite material that is optically transparent, densely filled with polymer, and has highly polarized optical properties. Calculations of absorption and emission anisotropies further indicate full incorporation of the polymer into the nanoscale pore spaces. Such materials could serve as a useful tool for further investigations of polymer photophysics, as well as for device applications. 相似文献
810.
Hiraoka S Okamoto T Kozaki M Shiomi D Sato K Takui T Okada K 《Journal of the American Chemical Society》2004,126(1):58-59
A stable radical-substituted radical ion with strongly ferromagnetic intramolecular interaction (J) between the radical and radical ion sites is an attractive spin building block of organic magnets. We prepared 2-nitronyl nitroxide-substituted 5,10-diphenyl-5,10-dihydrophenazine radical cation, 1+. The 1+ salt was stable under aerated conditions at room temperature and had a large J/kB value (>/=+700 K). 相似文献