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961.
Yousuke Miyashita Hiroshi Yokoyama Mamoru Tanabe Hitoshi Kasai Hachiro Nakanishi Tokuji Miyashita 《Journal of photochemistry and photobiology. A, Chemistry》2009,201(2-3):208-213
The photoexcited state of linear trans-quinacridone pigment nanoparticles, prepared by a reprecipitation method, was analyzed by time-resolved spectroscopy. The analysis showed that the S1 state of the linear trans-quinacridone nanoparticles undergoes a quantitative, non-radiative relaxation to the ground state with a time constant of about 100 ps. By contrast, the S1 state of the molecular dispersion state (dilute solution state) was relatively long-lived (21 ns). This, together with the intersystem crossing to T1 observed in the molecular dispersion state, clearly distinguished the nanoparticles from the molecular dispersion state. By comparing the two in terms of lightfastness, the nanoparticles were found to be much more lightfast than the molecular dispersion state. It was speculated that the superior lightfastness of the linear trans-quinacridone pigment nanoparticles was not due to the molecular structure but the facilitated S1 relaxation by the aggregation of the molecules. 相似文献
962.
S. Koyama M. Ozawa K. Kurosawa K. Tatenuma Y. Sato K. Okada 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(3):807-813
A multi-functional separation process is proposed as one of the technologies for implementing the Adv.-ORIENT (Advanced Optimization
by Recycling Instructive ElemeNTs) Cycle concept [1]. The tertiary pyridine-type anion exchange resin (TPR) embedded in silica beads (silica-supported TPR) was demonstrated
suitable for the separation process of actinides from spent fuel. In this process, hydrochloric acid (HCl) and a mixture of
nitric acid (HNO3) and methanol (MeOH) are used as eluents. In order to apply this process to an engineering plant scale, two important issues
must be evaluated to prove the system suitability. One is an environmental aspect represented by the use of HCl solution which
is corrosive to many materials. The other is clarification of the reactive safety of silica-supported TPR and the HNO3–MeOH solvent mixture. Four types of metals, Ta, Zr, Nb, and Hastelloy-B (28%Mo–Ni) were selected as candidate materials which
are anti-corrosive toward HCl. Corrosion experiments were conducted in HCl type simulated high level liquid waste (SHLLW)
solution at room temperature for a maximum 720 h and at 90 °C for 336 h. Ta showed an all-round anti-corrosion property in
HCl type SHLLW solution, and Hastelloy-B was only acceptable at room temperature. Thermal analysis by differential scanning
calorimetry was done to investigate the thermal stability of silica-supported TPR-NO3/MeOH/HNO3 mixtures. Heating experiment results on a gram scale were also obtained and evaluated to determine the conditions necessary
to avoid runaway reactions. As a result, it was confirmed that a vigorous exothermic reaction can be avoided by controlled
decrease of temperature. 相似文献
963.
Toru Matsui Takashi Togari Satoru Misawa Tomoyuki Namihira Naoya Shinzato Hitoshi Matsuda Seigo Sato 《Applied biochemistry and biotechnology》2010,162(3):823-829
Temperature shift cultivations with amino acid supplementation were optimized to produce porcine adenylate kinase (ADK) in
recombinant Escherichia coli harboring a pUC-based recombinant plasmid under the control of the trp promoter. With regard to temperature control, the culture condition was initially maintained at 35 °C for cellular growth,
but ADK expression was suppressed until the late logarithmic growth phase; subsequently, a temperature shift was applied (from
35 °C to 42 °C), which resulted in maximal ADK production. In addition, supplementation of amino acids, especially valine
and leucine, during the temperature shift stimulated ADK expression from 3.5% to 9.2% and 8.6% of the total protein, respectively.
After optimization, 1 g ADK per liter was produced within 16 h of cultivation with a dry cell weight of 21.8 g/l. In this
system, there was no loss of the recombinant plasmid during cultivation without selective pressure. 相似文献
964.
By taking an interest in a natural extension to the small parameters of the trace inequality for Morrey spaces, Orlicz–Morrey
spaces are introduced and some inequalities for generalized fractional integral operators on Orlicz–Morrey spaces are established.
The local boundedness property of the Orlicz maximal operators is investigated and some Morrey-norm equivalences are also
verified. The result obtained here sharpens the one in our earlier papers. 相似文献
965.
We prove a Godbillon?CVey index formula for longitudinal Dirac operators on a foliated bundle with boundary ${(X,\mathcal{F})}$ ; in particular, we define a Godbillon?CVey eta invariant on ${(\partial X,\mathcal{F}_{\partial}),}$ that is, a secondary invariant for longitudinal Dirac operators on type III foliations. Moreover, employing the Godbillon?CVey index as a pivotal example, we explain a new approach to higher index theory on geometric structures with boundary. This is heavily based on the interplay between the absolute and relative pairings of K-theory and cyclic cohomology for an exact sequence of Banach algebras, which in the present context takes the form ${0 \to \mathbf{\mathfrak{J}} \to \mathbf{\mathfrak{A}} \to \mathbf{\mathfrak{B}} \to 0}$ with ${ \mathbf{\mathfrak{J}}}$ dense and holomorphically closed in ${C^* (X,\mathcal{F})}$ and ${ \mathbf{\mathfrak{B}}}$ depending only on boundary data. Of particular importance is the definition of a relative cyclic cocycle ${(\tau_{GV}^r,\sigma_{GV})}$ for the pair ${\mathbf{\mathfrak{A}} \to \mathbf{\mathfrak{B}}}$ ; ${\tau_{GV}^r}$ is a cyclic cochain on ${\mathbf{\mathfrak{A}}}$ defined through a regularization à la Melrose of the usual Godbillon?CVey cyclic cocycle ?? GV ; ?? GV is a cyclic cocycle on ${\mathbf{\mathfrak{B}}}$ , obtained through a suspension procedure involving ?? GV and a specific 1-cyclic cocycle (Roe??s 1-cocycle). We call ?? GV the eta cocycle associated to ?? GV . The Atiyah?CPatodi?CSinger formula is obtained by defining a relative index class ${{\rm Ind} (D,D^\partial) \in K_* (\mathbf{\mathfrak{A}}, \mathbf{\mathfrak{B}})}$ and establishing the equality ${\langle {\rm Ind} (D), [\tau_{GV}] \rangle\,=\,\langle {\rm Ind} (D,D^\partial), [(\tau^r_{GV}, \sigma_{GV})] \rangle}$ . The Godbillon?CVey eta invariant ?? GV is obtained through the eta cocycle ?? GV . 相似文献
966.
In the present paper we obtain and extend the boundedness property of the Adams type for multilinear fractional integral operators. Also, we deal with the Olsen type inequality. 相似文献
967.
In this paper, we discuss our new synthetic approach towards functionalized benzo[d]thiazolyl (BT) sulfones, based on the reunion of alkyl BT sulfones and various electrophiles (e.g. R-CO-X, RO-CO-X, RS-CO-X, Ts-X…). All important aspects of this coupling reaction, including relevant and undesirable side reactions, are evaluated by means of calculations and competitive experiments. The scope and limitations of this method are established. 相似文献
968.
Nakabayashi K Nishio M Kubo K Kosaka W Miyasaka H 《Dalton transactions (Cambridge, England : 2003)》2012,41(20):6072-6074
A diagram of energies between the HOMO of donor (D) and LUMO of acceptor (A) vs.ΔE(1/2)(DA) (= E(1/2)(D) - E(1/2)(A): E(1/2) = first-redox potential) clearly demonstrates the ionicity in the series of D/A assemblies, [{Ru(2)(CF(3)CO(2))(4)}(2)(TCNQR(x))]·n(solv) (TCNQR(x) = 2,5- or 2,3,5,6-R-substituted 7,7,8,8-tetracyano-p-quinodimethane; R(x) = H(4), F(2), Cl(2), Br(2), F(4), Me(2), (OMe)(2)). 相似文献
969.
970.
Muhammad S Minami T Fukui H Yoneda K Kishi R Shigeta Y Nakano M 《The journal of physical chemistry. A》2012,116(5):1417-1424
Quantum molecular engineering has been performed to determine the second-order nonlinear optical (NLO) properties in different halo complexes of decaborane (B(10)H(14)) and their derivatives using the density functional theory (DFT) method. These decaborane halo complexes of X(-)@B(10)H(14) (X = F, Cl, Br, and I) are found to possess noncovalent charge transfer interactions. The static polarizability (α(0)) and first hyperpolarizability (β(0)) among these complexes increase by moving down the group from F to I, partly due to the increase in size of their anionic radii and the decrease in their electron affinities. A two-level approximation has been employed to investigate the origin of β(0) values in these halo complexes, which show very consistent results with those by the finite-field method. Furthermore, in the same line, two experimentally existing complexes, I(-)@B(10)H(14) and I(-)@2,4-I(2)B(10)H(12), are found to have considerably large β(0) values of 2859 and 3092 a.u., respectively, which are about three times larger than a prototypical second-order NLO molecule of p-nitroaniline, as reported by Soscun et al. [Int. J. Quantum Chem.2006, 106, 1130-1137]. Besides this, the special effects of solvent, counterion, and bottom substitutions have also been investigated. Interestingly, 2,4-alkali metal-substituted decaborane iodide complexes show remarkably large second-order NLO response with β(0) amplitude as large as 62436 a.u. for I(-)@2,4-K(2)B(10)H(12) complex, which are explained in terms of their transition energies, frontier molecular orbitals and electron density difference plots. Thus, the present investigation provides several new comparative insights into the second-order NLO properties of halo complexes of decaborane, which possess not only large first hyperpolarizabilities, but also high tunability to get a robustly large second-order NLO response by alkali metal substitution effects. 相似文献