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911.
Ikuma Kuroda Yukihiro Shintani Masanori Motokawa Shuzo Abe Masahiro Furuno 《Analytical sciences》2004,20(9):1313-1319
A methodology of phosphopeptide-selective analysis coupled with column-switching HPLC utilizing titania as precolumn media is presented. Phosphopeptides were selectively enriched on titania packing within a protein/peptide mixture without any additional procedure, and analyzed by column-switching high-performance liquid chromatography. First, phospho-compounds were separated from complex mixtures by trapping them under acidic conditions on a titania packing, where non-phosphorylated compounds were effused out of the precolumn. Subsequently, phospho-compounds were desorbed from the titania column under a specific condition and analyzed. The behavior of phospho-compounds on a titania surface, especially adsorption/desorption, was precisely examined and optimized. A phosphoric buffer was successively employed for the elution of phosphopeptides on a titania surface by competition with the free phosphate group. From the successes of a selective concentration/analysis of phosphopeptides with column-switching HPLC with a titania precolumn, a novel phosphopeptide-selective RP-HPLC analysis has been shown to have an application possibility as a tool for phosphoproteomics. 相似文献
912.
Masanori Mitsui Yuri Murakami Takashi Obi Masahiro Yamaguchi Nagaaki Ohyama 《Optical Review》2005,12(2):69-75
We propose a new method for the color enhancement of multispectral image in the visible wavelength region. The purpose of the proposed method is to explore the weak features contained in a specific wavelength by discounting the major color distribution. Such examination will be valuable in visual inspection applications, for example, a medical examination using color image to find a small spectral change of an abnormal part. In this method, Karhunen-Loeve (KL) transform is applied to multispectral data, and specific wavelength components of only high-order KL coefficients are amplified while low-order coefficients are not changed to retain the major color distribution. In the experiment, this method was applied to multispectral images: a printed test image and a human skin image of a bruised arm were captured by a 16-band multispectral camera. The resultant images were compared with the images obtained by saturation enhancement and that obtained by applying the proposed method to the 3-band image. The method successfully visualized the features, which are almost invisible in natural color images, with less change in background color than saturation enhancement. 相似文献
913.
Masahiko Tani Yuichi Hirota Christopher T. Que Shigehisa Tanaka Ryo Hattori Mariko Yamaguchi Seizi Nishizawa Masanori Hangyo 《International Journal of Infrared and Millimeter Waves》2006,27(4):531-546
The photoconductive (PC) antenna is a key device for the recent terahertz (THz) photonics based on laser-pumped generation
and detection of THz radiation. In this paper we report on two new types of PC antennas: the Schottky PC antenna and the multi-contacts
PC antenna. The former one is able to detect THz radiation intensity without the time-delay scan and useful for applications
where spectroscopic information is not important, such as the THz intensity imaging. The latter one is useful for the polarization
sensitive THz spectroscopy, such as the THz ellipsometry. The characteristic features of these new types of PC antennas are
studied by using a THz time-domain spectroscopy system. 相似文献
914.
In this paper, we consider two-dimensional N=(4,4) supersymmetric Yang-Mills (SYM) theory and deform it by a mass parameter M with keeping all supercharges. We further add another mass parameter m in a manner to respect two of the eight supercharges and put the deformed theory on a two-dimensional square lattice, on which the two supercharges are exactly preserved. The flat directions of scalar fields are stabilized due to the mass deformations, which gives discrete minima representing fuzzy spheres. We show in the perturbation theory that the lattice continuum limit can be taken without any fine tuning. Around the trivial minimum, this lattice theory serves as a non-perturbative definition of two-dimensional N=(4,4) SYM theory. We also discuss that the same lattice theory realizes four-dimensional N=2U(k) SYM on R2×(Fuzzy R2) around the minimum of k-coincident fuzzy spheres. 相似文献
915.
Munehiro Inukai Masanori Tamura Satoshi Horike Masakazu Higuchi Susumu Kitagawa Koichi Nakamura 《Angewandte Chemie (International ed. in English)》2018,57(28):8687-8690
Design to store gas molecules, such as CO2, H2, and CH4, under low pressure is one of the most important challenges in chemistry and materials science. Herein, we describe the storage of CO2 in the cavities of a porous coordination polymer (PCP) using molecular rotor dynamics. Owing to the narrow pore windows of PCP, CO2 was not adsorbed at 195 K. As the temperature increased, the rotors exhibited rotational modes; such rotations dynamically expanded the size of the windows, leading to CO2 adsorption. The rotational frequencies of the rotors (k≈10?6 s) and correlation times of adsorbed CO2 (τ≈10?8 s) were elucidated via solid‐state NMR studies, which suggest that the slow rotation of the rotors sterically restricts CO2 diffusion in the pores. This restriction results in an unusually slow CO2 mobility close to solid state (τ≥10?8 s). Once adsorbed at room temperature, CO2 is robustly stored in the PCP under vacuum at 195–233 K because of the steric hindrance of the rotors. We also demonstrate that this mechanism can be applied to the storage of CH4. 相似文献
916.
Analysis of exponent values of Gaussian‐type functions on quantum protons and deuterons in charged or polarized systems 下载免费PDF全文
Marina Hashimoto Takayoshi Ishimoto Masanori Tachikawa Taro Udagawa 《International journal of quantum chemistry》2016,116(12):961-970
The optimal exponent α values (αopt) in s‐type Gaussian‐type functions (GTFs) for quantum protons and deuterons, which are used for multicomponent molecular orbital calculations including nuclear quantum nature of protons and deuterons, are analyzed for several charged or polarized systems and their deuterated species. Ishimoto and coworkers (Ishimoto, Int. J. Quantum Chem. 2006 , 106, 1465) have already proposed the average exponent values for five neutral molecules (αave), and demonstrated that their αave enables us to evaluate the H/D isotope effect on energies and geometries of various neutral species. The differences between total energies of several charged or polarized systems with previous αave and our αopt correspond to only less than 0.004% of the total energy (0.47 kcal·mol?1) except for HeH+ and HeD+ molecules, while the difference between interaction energies of H2OH+…OH2 and H2OD+…OH2 systems with previous αave is 19% (0.22 kcal·mol?1) smaller than that with our αopt. Meanwhile, the difference between O? H bond lengths in H2OH+…OH2 system with αave and αopt values is 0.027 Å. We also found that the interaction energies with αopt value at the geometry optimized with previous αave value (αsp) well reproduce those at the geometry optimized with αopt value. We have demonstrated that the nuclear basis functions based on s‐type GTFs with previous αave values enable us to evaluate the H/D isotope effect on energies and geometries of charged or polarized systems. © 2016 Wiley Periodicals, Inc. 相似文献
917.
Md. Ashraf Ali Shuji Noguchi Miteki Watanabe Yasunori Iwao Shigeru Itai 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(10):743-747
7‐Ethyl‐10‐hydroxycamptothecin [systematic name: (4S)‐4,11‐diethyl‐4,9‐dihydroxy‐1H‐pyrano[3′,4′:6,7]indolizino[1,2‐b]quinoline‐3,14(4H,12H)‐dione, SN‐38] is an antitumour drug which exerts activity through the inhibition of topoisomerase I. The crystal structure of SN‐38 as the monohydrate, C22H20N2O5·H2O, reveals that it is a monoclinic crystal, with one SN‐38 molecule and one water molecule in the asymmetric unit. When the crystal is heated to 473 K, approximately 30% of SN‐38 is hydrolyzed at its lactone ring, resulting in the formation of the inactive carboxylate form. The molecular arrangement around the water molecule and the lactone ring of SN‐38 in the crystal structure suggests that SN‐38 is hydrolyzed by the water molecule at (x, y, z) nucleophilically attacking the carbonyl C atom of the lactone ring at (x − 1, y, z − 1). Hydrogen bonding around the water molecules and the lactone ring appears to promote this hydrolysis reaction: two carbonyl O atoms, which are hydrogen bonded as hydrogen‐bond acceptors to the water molecule at (x, y, z), might enhance the nucleophilicity of this water molecule, while the water molecule at (−x, y + , −z), which is hydrogen bonded as a hydrogen‐bond donor to the carbonyl O atom at (x − 1, y, z − 1), might enhance the electrophilicity of the carbonyl C atom. 相似文献
918.
For increasing the data density of holographic data storage (HDS), combining more than two multiplexing techniques is effective. This is also true in self-referential holographic data storage (SR-HDS) that enables holographic recording purely with a single beam. In this paper, a focus-shift multiplexing technique is applied to \(xy\)-shift multiplexed SR-HDS, the feasibility of which has been shown in our previous work. The focus-shift multiplexing technique enables the multiplexing of datapages by slightly changing the focal length of the objective lens. However, the required focus-shift distance for multiplexing and the implementation method of the focus-shift have not been clarified. First, the focus-shift selectivity is investigated by the numerical simulations. In the case where the focus-shift multiplexing technique is applied to \(xy\)-shift multiplexed SR-HDS, the inter-page crosstalk properties are clarified to decide the recording layout that can achieve a low-crosstalk readout. Second, the technique of displaying an additional phase pattern onto the spatial light modulator (SLM) is introduced, which is a focus-shift method without any special optical components, such as varifocal lenses. Finally, we investigate the relationship between the accuracy of the focus-shift and the parameters of SLM. 相似文献
919.
Ando Masanori Kamimura Takuya Uegaki Koichi Biju Vasudevanpillai Shigeri Yasushi 《Mikrochimica acta》2016,183(11):3019-3024
Microchimica Acta - Thin films of CdSe-based core-shell type quantum dots (CdSe/CdZnS, CdSe/ZnS and CdSeTe/ZnS) deposited on glass substrate were found to undergo a reversible change in... 相似文献
920.
We analyze random walk in the upper half of a three-dimensional lattice which goes down whenever it encounters a new vertex,
a.k.a. excited random walk. We show that it is recurrent with an expected number of returns of . 相似文献