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81.
Morphology and properties of globular polymeric materials in the solid state: A composite material of DNA with a cationic surfactant 下载免费PDF全文
Emmanuel C. Ossai Yuka Tomimori Shota Ohki Koki Okada Takeshi Yonekura Kazuya Furusawa Naoki Sasaki 《Journal of Polymer Science.Polymer Physics》2016,54(7):730-738
The aim of the present study was to control entanglements in order to regulate the properties of polymeric solids. Initially, fabrication of polymeric solids with few entanglements was attempted. Films of the DNA–cationic surfactant, cetyltrimethylammonium bromide (CTAB) (DNA–CTA), were cast from ethanol solution at room temperature. Morphological examination of DNA–CTA complex films using atomic force microscopy (AFM) revealed that these films were constructed by particle‐like substances. Geometrical analysis of AFM images showed that the particle‐like substances were the aggregates of several DNA–CTA globules. Mechanical characterization suggested that there were fewer entanglements than with normal plastic films. Small angle X‐ray scattering experiments during annealing indicated that molecular motions were highly excited in the surface region of each particle. In conclusion, a globular polymeric film with fewer entanglements was fabricated. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 730–738 相似文献
82.
Theoretical Study on the Relationship between Diradical Character and Second Hyperpolarizabilities of Four‐Membered‐Ring Diradicals Involving Heavy Main‐Group Elements 下载免费PDF全文
Hiroshi Matsui Kotaro Fukuda Shota Takamuku Prof. Dr. Akira Sekiguchi Prof. Dr. Masayoshi Nakano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):2157-2164
By using spin‐unrestricted density functional theory methods, the relationship between the diradical character y and the second hyperpolarizability γ (the third‐order nonlinear optical (NLO) properties at the molecular scale) for four‐membered‐ring diradical compounds, that is, cyclobutane‐1,3‐diyl, Niecke‐type diradicals, and Bertrand‐type diradicals, were investigated by focusing on the substitution effects of heavy main‐group elements as well as of donor/acceptor groups on the y and γ values. It has been found that i) γ is enhanced in the intermediate y region for these four‐membered‐ring diradicals, ii) Niecke‐type diradicals with intermediate y values, which are realized by tuning the combination of the main‐group elements involved, exhibit larger γ values than Bertrand‐type diradicals, and iii) the y value and thus γ value can be controlled by modifying the both‐end donor/acceptor substituents attached to carbon atoms in Nicke‐type C2P2 diradicals. These results demonstrate that four‐membered‐ring diradicals involving heavy main‐group elements exhibit high controllability of the y and γ, which indicates the potential applications of four‐membered‐ring diradicals as a building block of highly efficient open‐shell NLO materials. 相似文献
83.
Versatile Oxidation Methods for Organic and Inorganic Substrates Catalyzed by Platinum‐Group Metals on Carbons 下载免费PDF全文
Yoshinari Sawama Shota Asai Yasunari Monguchi Hironao Sajiki 《Chemical record (New York, N.Y.)》2016,16(1):261-272
Platinum‐group metals on activated carbon catalysts, represented by Pd/C, Ru/C, Rh/C, etc., are widely utilized to accomplish green and sustainable organic reactions due to their favorable features, such as easy handling, recoverability, and reusability. The efficient oxidation methods of various organic compounds using heterogeneous platinum‐group metals on carbons with or without added oxidants are summarized in this Personal Account. The oxidation of internal alkynes into diketones was effectively catalyzed by Pd/C in the presence of dimethyl sulfoxide and molecular oxygen or pyridine N‐oxide. The Pd/C‐catalyzed mild combustion of gaseous hydrogen with molecular oxygen provided hydrogen peroxide, which could be directly utilized for the oxidation of sulfide derivatives into sulfoxides. Furthermore, the Ru/C‐catalyzed aerobic oxidation of primary and secondary alcohols gave the corresponding aldehydes and ketones, respectively. On the other hand, the dehydrogenative oxidation of secondary alcohols into ketones was achieved using Rh/C in water, and primary alcohols were effectively dehydrogenated by Pd/C in water under mildly reduced pressure to produce carboxylic acids.
84.
Atsushi Funada Shota Uchikawa Dr. Norihisa Hoshino Dr. Takashi Takeda Prof. Tomoyuki Akutagawa 《化学:亚洲杂志》2016,11(6):915-925
The phase‐transition behaviors, crystal structures, and dielectric properties of four kinds of simple 1:1 organic salts of (C12H25NH3+)(benzenesulfonate) and (C12H25NH3+)(pyridine sulfonates) were examined from the viewpoint of intermolecular hydrogen‐bonding interactions and dynamic conformational transformation in molecular assemblies. Crystals of (C12H25NH3+)(benzenesulfonate) and (C12H25NH3+)(3‐pyridinesulfonate) were isostructural and solid–solid and solid–liquid‐crystal smectic A (SmA) phase transitions were observed. These two crystals formed rodlike cation–anion assemblies. However, the two salts, (C12H25NH3+)(2‐pyridinesulfonate) and (C12H25NH3+)(4‐pyridinesulfonate), formed largely bent L ‐shaped cation–anion conformations. Interesting conformational transformations from rodlike to L ‐shaped assemblies were observed in (C12H25NH3+)(2‐pyridinesulfonate) and (C12H25NH3+)(3‐pyridinesulfonate). 相似文献
85.
Shota Ooi Dr. Takayuki Tanaka Kyu Hyung Park Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2016,55(22):6535-6539
The oxidation of 10–10′ singly linked corrole dimers with DDQ at low concentration in CHCl3 afforded meso–meso, β–β, β–β triply linked 2H‐corrole dimers (with two inner NH groups in each corrole unit), which exhibited characteristic 1H NMR and absorption spectra attributable to their nonaromatic electronic networks. These 2H‐corrole dimers were reduced with NaBH4 to aromatic 3H‐corrole dimers, which were unstable and easily oxidized back to the 2H‐corrole dimers upon exposure to air. Bis(zinc(II)) complexes of the 2H‐corrole dimers were synthesized and characterized as rare examples of nonaromatic zinc(II) corrole complexes. 相似文献
86.
Shota Sato 《Journal of Mathematical Analysis and Applications》2008,343(2):1061-1074
We investigate the initial-boundary problem
87.
2-DE is one of the most powerful methods for analyzing proteins expressed in cells and tissues. Immunodetection of proteins blotted on a polymer membrane is the method of choice for detecting specific proteins in 2-D gels. To precisely locate spots of immunoreactive proteins in 2-D gels, both dye staining and immunodetection were performed on the same PVDF membrane. Prior to immunodetection, nonspecific adsorption of the antibodies to the membrane was blocked with a synthetic polymer-based reagent (N-102) after protein transfer. The protein was then stained with colloidal gold or CBB followed by protein spot identification by LC-MS. Described herein is a method for multiplex analysis of proteins transferred to a PVDF membrane. Proteins that were phosphorylated at tyrosine in the phosphoproteome of rice callus or human ovarian cancer cells were detected by immunoblotting and subsequently identified with high precision. 相似文献
88.
Yasuya Kudo Kazunori Koiwai Kazuhiro Shimizu Shota Kusuki Mina Sakuragi Naohiko Shimada Yoichi Takeda Kazuo Sakurai 《中国化学快报》2008,19(9):1115-1118
A lipoplex (i.e., pDNA#1/lipid complex and transfection reagent for pDNA delivery) containing galactosylceramide (GalCer) and an amidine-bearing lipid (TRX) was examined whether the bound pDNA was specifically ingested by hepatocyte via asialoglycoprotein receptor (ASGPR) and then expressed protein. Gel electrophoresis and small-angle X-ray scattering (SAXS) confirmed that the TRX-GalCer liposome#2 complexed with pDNA and the resultant lipoplex took a hexagonally packed inverted cylinder structure when the GalCer composition was less than 20 wt.% of the total lipid. When the lipoplex carrying pGL3 (luciferase-cording pDNA) was administrated to HepG2, the luciferase activity was increased with increasing the GalCer composition until it reached 3 wt.% and then decreased upon further addition of GalCer. When we added galactose itself as a competitor, the luciferase activity was decreased, while glucose did not show such decrease, suggesting that HepG2 ingested the lipoplex via ASGPR-mediated endocytosis. This paper indicated that the hexagonally packed inverted cylinder structures of lipoplex may not always provide excellent transfection and presented a possibility that the TRX lipoplex#3 can obtain a cellulartargeting ability through the receptors for oligosaccharide. 相似文献
89.
Abdou Tchoukoua Turibio Kuiate Tabopda Shota Uesugi Ken‐ichi Kimura Eunsang Kwon Hiroyuki Momma Bonaventure Tchaleu Ngadjui Takuya Koseki Yoshihito Shiono 《Magnetic resonance in chemistry : MRC》2016,54(11):893-896
Phytochemical investigation of the roots of Albizia chevalieri led to the isolation of two new 5‐deoxyflavan‐3,4‐diol glucosides from roots of A. chevalieri, Chevalieriflavanosides A and B. Their structures were established by 2D NMR techniques, UV, IR, CD, and mass spectrometry. Cytotoxicity of the two compounds was evaluated against acute promyelocytic leukemia HL60 cells. The antibacterial activities of 1 and 2 also were evaluated against Pseudomonas aeruginosa and Staphylococcus aureus using the agar diffusion test. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
90.
Shota Sasaki Toru Ube Kenji Katayama Masayasu Muramatsu Hiroshi Miyasaka 《Molecular Crystals and Liquid Crystals》2018,662(1):53-60
ABSTRACTWe prepared crosslinked azotolane liquid-crystalline polymer (LCP) films doped with a stilbene derivative (two-photon chromophore) utilizing an interpenetrating polymer network (IPN) structure. The IPN films bend toward the light source upon irradiation with femtosecond laser pulses at 600 nm, which can excite the stilbene derivative by two-photon absorption. The bending speed of the IPN films increases with the square of the laser pulse intensity, which is compelling evidence for the two-photon processes. 相似文献