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11.
Polymer microspheres composed of various compositions of styrene and 2-hydroxyethyl methacrylate (HEMA) were produced by batch emulsifier-free emulsion polymerization. The HEMA content at the surface, [HEMA]
s
, of the microspheres powdered by freeze-drying was determined by both quantitativeC
1s
/O
1s
analysis andC
1s
peak shape analysis of the x-ray photoelectron spectroscopic spectra. When the HEMA content in the microsphere, [HEMA]
p
, was less than about 5 mole%, the [HEMA]
s
values determined by the two different methods showed good agreement. At [HEMA]p above 5 mole %, [HEMA]s values determined by the first method were about 15 mole % greater than those determined by the second. They both showed a similar tendency with the [HEMA]
s
being higher than the [HEMA]
p
, e.g., when [HEMA]
p
was 1 mole %, [HEMA]
s
was 11 mole %. The intensity of the satellite peak due to the
* transition of the benzene ring of the styrene component decreased with an increase in [HEMA]
p
, to zero at 5 mole % of [HEMA]
p
. These results indicate that the HEMA component is localized at the surface.Part CVIII of the series Studies on Suspension and Emulsion. 相似文献
12.
[reaction: see text] We have developed an efficient copper-catalyzed allylation of carbonyl derivatives using allyl(2-pyridyl)silanes, in which the strong directing effect of the 2-pyridyl group was observed. A useful synthesis and allylation of substituted allyl(2-pyridyl)silanes is also described. 相似文献
13.
14.
Hao Wang Dr. Shutao Wang Dr. Helen Su Dr. Kuan‐Ju Chen Amanda Lee Armijo Wei‐Yu Lin Dr. Yanju Wang Dr. Jing Sun Dr. Ken‐ichiro Kamei Dr. Johannes Czernin Prof. Caius G. Radu Prof. Hsian‐Rong Tseng Prof. 《Angewandte Chemie (International ed. in English)》2009,48(24):4344-4348
A supramolecular approach has been developed for the preparation of supramolecular nanoparticles (SNPs) with variable sizes (30–450 nm) from three different molecular building blocks using a cyclodextrin/adamantane recognition system. Positron emission tomography (PET) was employed to study the biodistribution and lymph node drainage of the SNPs in mice. The sizes of the SNPs affect their in vivo characteristics (see picture).
15.
Daisuke Kamei Hiroharu Ajiro Mitsuru Akashi 《Journal of polymer science. Part A, Polymer chemistry》2010,48(16):3651-3657
The effects of stereoregularity, temperature, and solvent on the specific recognition of syndiotactic (st)‐poly(methacrylic acid) (PMAA) in macromolecularly porous isotactic (it)‐poly(methyl methacrylate) films were investigated to give important insights into the regularity and stability of nanospaces in the it‐PMMA films as well as template polymerization. The porous it‐PMMA films were fabricated on quartz crystal microbalance (QCM) substrates via the layer‐by‐layer (LbL) assembly of it‐PMMA/st‐PMAA, plus the st‐PMAA extraction from the assembly. QCM analysis and infrared spectroscopy revealed the first case of stereocomplex formation using st‐PMAA with lower stereoregularity (rr = 73%) in the LbL films, while st‐PMAA obtained with conventional free radical polymerization (rr = 62%) was barely incorporated into the porous it‐PMMA films. The maximum st‐PMAA incorporation increased from 25 to 40 °C, but there were almost no difference between 40 and 55 °C, indicating that the it‐PMMA crystallization would also be accelerated with increasing temperature. The studies on st‐PMAA incorporation with various complexing solvents revealed that the host it‐PMMA in the porous films could only form the original stereocomplex with 2/1 unit‐molar stoichiometry (st‐PMAA/it‐PMMA) in acetonitrile/water or ethanol/water. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3651–3657, 2010 相似文献
16.
Nobuyuki Tamaoki Takashi Kamei 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2010,11(2-3):47-61
Photochromic reactions in liquid crystals induce re-alignments of the host molecules, accompanied by changes in the optical properties and various other properties of the materials. Since the first report by Sackmann in 1971, various combinations of photochromic compounds and liquid crystals have been studied to elicit the reversible photo-regulated changes of various properties. In this report we review the advances of this field during the past 5 years, which include the creation of mechanical functions, the regulation of novel optical properties, cholesteric liquid crystals doped with azobenzene compounds in high concentrations, the regulation of ferroelectric liquid crystals, the induction of chirality by circularly polarized light, photoresponsive chiral dopants, and the photo-regulation of the oscillation wavelength of mirrorless lasers. 相似文献
17.
A reductive transmetalation of the pi-allylpalladium(II) complexes, generated in situ from a catalytic amount of a palladium(0) complex and a variety of allylic substrates, with indium(I) salts proceeded smoothly in various solvents, providing a new route for allylindium(III) reagents. 相似文献
18.
Copper‐Catalyzed CH Bond Direct Chalcogenation of Aromatic Compounds Leading to Diaryl Sulfides,Selenides, and Diselenides by Using Elemental Sulfur and Selenium as Chalcogen Sources Under Oxidative Conditions 下载免费PDF全文
Prof. Fumitoshi Shibahara Takafumi Kanai Eiji Yamaguchi Akika Kamei Takayuki Yamauchi Prof. Toshiaki Murai 《化学:亚洲杂志》2014,9(1):237-244
The reactions of aromatic compounds and elemental chalcogens catalyzed by a copper salt with molecular oxygen as an oxidant were carried out. The reaction of 3‐substituted imidazo[1,5‐a]pyridines and elemental sulfur in the presence of CuTC (copper(I) thiophenecarboxylate) gave the corresponding bisimidazopyridyl sulfides in good to quantitative yields. The reaction proceeded even under aerobic oxidation conditions. The use of a polar solvent was crucial for the reaction, and DMSO (dimethyl sulfoxide) in particular stimulated the reaction. The reaction could be applied to common aromatic compounds, such as N‐methyl indole and dialkyl anilines. The reaction of indole proceeded at the nucleophilic C3 position rather than at the acidic C2 position. In addition, the reaction of dialkyl anilines proceeded with an ortho, para orientation. The reactions of imidazopyridines and elemental selenium under similar conditions gave the corresponding bisimidazopyridyl diselenides along with bisimidazopyridyl monoselenides. The resulting diselenides were readily converted to the corresponding monoselenides with unreacted imidazopyridines under the same conditions. The reaction could be applied to the copolymerization of bifunctional bisimidazopyridines and elemental sulfur to give oligomeric copolymers in quantitative yield. 相似文献
19.
Sakihito Kitajima Kaeko Kamei Shigeru Taketani Masamitsu Yamaguchi Fumiko Kawai Aino Komatsu Yoshihiro Inukai 《BMC biochemistry》2010,11(1):6
Background
Plant latex is the cytoplasm of highly specialized cells known as laticifers, and is thought to have a critical role in defense against herbivorous insects. Proteins abundantly accumulated in latex might therefore be involved in the defense system. 相似文献20.
Rahim MK Fukaminato T Kamei T Tamaoki N 《Langmuir : the ACS journal of surfaces and colloids》2011,27(17):10347-10350
The gliding motility of microtubules driven by kinesin on the surface of an azobenzene monolayer presenting lysine terminal groups is reversibly and repeatedly altered upon photoisomerization of the monolayer. 相似文献