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81.
On the basis of the quantum white noise theory we introduce the notion of creation- and annihilation-derivatives of Fock space
operators and study the differentiability of white noise operators. We define the Hitsuda–Skorohod quantum stochastic integrals
by the adjoint actions of quantum stochastic gradients and show explicit formulas for their creation- and annihilation-derivatives.
As an application, we derive direct formulas for the integrands in the quantum stochastic integral representation of a regular
quantum martingale.
Work supported by the Korea–Japan Basic Scientific Cooperation Program “Noncommutative Stochastic Analysis and Its Applications
to Network Science.” 相似文献
82.
83.
By the use of catalytic amounts of a nickel salt and a 1,3-butadiene, primary and secondary alkyl Grignard reagents undergo cross-coupling with alkyl bromides, iodide, and tosylate carrying a functional group such as amide, ester, and ketone at 0 °C in THF. The present procedure provides a simple, convenient, and practical method for construction of carbon chains in the presence of various functional groups. PhMgBr also gave the corresponding coupling product in a moderate yield. 相似文献
84.
De Lie An Qiang Chen Hong Yan Nobuaki Miura Kenji Monde Junzo Otera 《Tetrahedron letters》2009,50(15):1689-1692
Stereochemical study of cyclophynes, which is otherwise rather difficult to perform, can be achieved by vibrational CD spectroscopy. 相似文献
85.
The phenolic-group capacities of five humic substances, such as, the Aldrich humic acid, the humic and fulvic acids extracted from a soil, the humic and fulvic acids extracted from a peat have been precisely determined by the non-aqueous potentiometric titration technique. The titration by KOH in the mixed solvent of DMSO:2-propanol:water = 80:19.3:0.7 at [K+] = 0.02 M enabled to measure the potential change in a wide range of pOH (=−log [OH−]), and thus to determine the capacities of phenolic groups which could not be precisely determined in the aqueous titration. The results of the titration revealed that the mean protonation constants of the phenolic groups were nearly the same for all humic substances and close to that of phenol in the same medium, indicating that each phenolic-group in the humic substances is rather isolated and is not electronically affected by other affecting groups in the humic macromolecule. 相似文献
86.
Nobuaki Seiji Tomoyuki Shuji Yasukazu 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2000,1(2)
New research fields have opened up that are related to the interactions between molecules and high-intensity optical fields where the laser intensity ranges from 1012–1017 W cm−2. A broad outline of this area will be described from the perspective of products and new techniques for beam generation. Studies of large molecules have begun and some examples are introduced herein. Parent ions with little fragmentation are found to form in the intensity region below 1016 W cm−2. The formation of intact ions can be used in femtosecond laser mass spectrometry. In the intensity region above 1016 W cm−2, electrons are stripped from the molecules by optical field ionization and the highly charged ions can undergo a Coulomb explosion. Coulomb explosions of benzene and C60 have been demonstrated, and the mechanism can be analyzed by means of molecular dynamics simulations. A high intensity femtosecond laser beam can be converted to radiation sources of coherent VUV light, X-rays etc. and some possibilities for new chemical applications will be discussed. 相似文献
87.
Extraction solvents for pressurized liquid extraction (PLE) used to extract polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) from contaminated soil were investigated. The PCDD/PCDFs and Co-PCBs in Certified Reference Material: CRM 0422 (Forest soil) were extracted using toluene, n-hexane, acetone, acetone/toluene and acetone/n-hexane (1:1, v/v). Soxhlet extraction was the reference method. Results demonstrated that PLE using mixed solvents produced better analyte recoveries than the single solvents. However, these results were lower than those for Soxhlet extraction. Additional extraction cycles using mixed solvents achieved better recovery results. Mixed solvents and several extraction cycles were necessary for satisfactory extraction of more tightly bound PCDD/PCDFs and Co-PCBs from soil. 相似文献
88.
Koizumi M Naito S Haishi T Utsuzawa S Ishida N Kano H 《Magnetic resonance imaging》2006,24(8):1111-1119
The thawing process for boiled and frozen edible vegetables was traced by a dedicated MRI for food research. The MRI system is small, with a 1.0-T static magnetic field, and can be placed in an ordinary research room with a light air conditioner. Images of green soybeans, broad beans, okra, asparagus and taro were measured by the spin-echo method (echo time=7 ms) with 0.1 or 0.2 s and 1 s repetition times. The images appeared along with the thawing time, and signals uniformly covered the sliced plane of the samples in the thawed condition. Information about the thawing process and tissue structures of the materials was obtained during transit thawing conditions. The thawing kinetics were examined with increased signal intensity, which were divided into two types. The signal increased linearly and saturated for okra and asparagus but exhibited convex curves for soybeans, broad beans and taro. The small MRI was stable, its handling was simple, and the internal structures of food materials could be accurately identified, although the grey-scale of the images was insufficient for determining precise textural fluctuations of tissue organization. We conclude that the devised MRI is useful for examining the quality of frozen foods and for developmental research into frozen foods. 相似文献
89.
Yamada M Yao I Hayasaka T Ushijima M Matsuura M Takada H Shikata N Setou M Kwon AH Ito S 《Analytical and bioanalytical chemistry》2012,402(5):1921-1930
Direct tissue analysis using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) provides the means
for in situ molecular analysis of a wide variety of biomolecules. This technology—known as imaging mass spectrometry (IMS)—allows
the measurement of biomolecules in their native biological environments without the need for target-specific reagents such
as antibodies. In this study, we applied the IMS technique to formalin-fixed paraffin-embedded samples to identify a substance(s)
responsible for the intestinal obstruction caused by an unidentified foreign body. In advance of IMS analysis, some pretreatments
were applied. After the deparaffinization of sections, samples were subjected to enzyme digestion. The sections co-crystallized
with matrix were desorbed and ionized by a laser pulse with scanning. A combination of α-amylase digestion and the 2,5-dihydroxybenzoic
acid matrix gave the best mass spectrum. With the IMS Convolution software which we developed, we could automatically extract
meaningful signals from the IMS datasets. The representative peak values were m/z 1,013, 1,175, 1,337, 1,499, 1,661, 1,823, and 1,985. Thus, it was revealed that the material was polymer with a 162-Da unit
size, calculated from the even intervals. In comparison with the mass spectra of the histopathological specimen and authentic
materials, the main component coincided with amylopectin rather than amylose. Tandem MS analysis proved that the main components
were oligosaccharides. Finally, we confirmed the identification of amylopectin by staining with periodic acid-Schiff and iodine.
These results for the first time show the advantages of MALDI-IMS in combination with enzyme digestion for the direct analysis
of oligosaccharides as a major component of histopathological samples. 相似文献
90.
Nobuaki Hoshino 《Annals of the Institute of Statistical Mathematics》2012,64(3):457-474
The present article investigates a class of random partitioning distributions of a positive integer. This class is called
the limiting conditional compound poisson (LCCP) distribution and characterized by the law of small numbers. Accordingly the
LCCP distribution explains the limiting behavior of counts on a sparse contingency table by the frequencies of frequencies.
The LCCP distribution is constructed via some combinations of conditioning and limiting, and this view reveals that the LCCP
distribution is a subclass of several known classes that depend on a Bell polynomial. It follows that the limiting behavior
of a Bell polynomial provides new asymptotics for a sparse contingency table. Also the Neyman Type A distribution and the
Thomas distribution are revisited as the basis of the sparsity. 相似文献