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131.
Ohne Zusammenfassung 相似文献
132.
A new diene has been synthesized which effectively couples the Diels-Alder reaction with the Claisen rearrangement. 相似文献
133.
134.
Zhao Y Higashihara T Sugiyama K Hirao A 《Journal of the American Chemical Society》2005,127(41):14158-14159
Novel 3-arm ABC, 4-arm ABCD, and 5-arm ABCDE asymmetric star polymers comprising the conductive polyacetylene precursor, poly(4-methylphenyl vinyl sulfoxide) (PMePVSO), and other segments, such as polystyrene, poly(alpha-methylstyrene), poly(4-methoxystyrene), poly(4-trimethylsilylstyrene), and poly(4-methylstyrene), were synthesized by the methodology based on living anionic polymerization using DPE-functionalized polymers. This methodology involves the addition reaction of a DPE-functionalized polymer to a living anionic polymer followed by the living anionic polymerization of MePVSO initiated from the in situ formed polymer anion with two, three, or four polymer segments. The resultant asymmetric star polymers possessed predetermined molecular weights, narrow molecular weight distributions (Mw/Mn < 1.03), and desired compositions as confirmed by SEC, 1H NMR, SLS, and elemental analysis. After thermal treatment, the PMePVSO segment in the star polymer could be completely converted into a conductive polyacetylene segment, evident from TGA and elemental analysis. These asymmetric star polymers are expected to exhibit interesting solution properties and unique microphase-separated morphological suprastructures with potential applications in nanoscopic conductive materials. Moreover, this methodology can afford the target asymmetric star polymers with arm segments varying in a wide range and enables the synthesis of more complex macromolecular architectures. 相似文献
135.
Ohne Zusammenfassung 相似文献
136.
Cellulose composites were produced by culturing Acetobacter aceti subsp. xylinum (ATCC 53524, agitation tolerant strain) under shaking and agitating conditions in the presence of 2% pine or beech Björkman lignin-carbohydrate complexes (LCCs) or six different types of hemicellulosic polysaccharides including glucuronoxylan, glucomannan, O-acetyl-glucuronoxylan, arabinoglucuronoxylan, arabinogalactan and xyloglucan. Hemicellulosic polysaccharide contents in cellulose composites were similar in spite of the differences in culture, shaking and agitating conditions. On the basis of hemicellulosic polysaccharide contents and X-ray diffraction patterns after extraction by dilute NaOH solution, glucomannan family polysaccharides were found to have the highest affinity to bacterial cellulose. Composites with neutral and acidic LCCs were resistant against alkali while high lability of their delignified carbohydrates against alkali indicates the importance of lignin for formation of cellulose-hemicellulose-lignin framework of plant secondary cell-walls. 相似文献
137.
138.
H. Ikezoe N. Shikazono Y. Tomita K. Ideno Y. Sugiyama E. Takekoshi 《Nuclear Physics A》1985,444(2):349-364
Velocity spectra of fusion-like residues produced in the reactions of 90 MeV and 150 MeV 16O with 27Al were measured. At 90 MeV the velocity spectra were well reproduced by a statistical model calculation. At 150 MeV the observed centroids of the velocity spectra deviate from the statistical model predictions. The centroid shifts as a function of the atomic and mass numbers of evaporation residues were analyzed by two different model calculations based on the assumption that incomplete fusion is (a) a peripheral process, or (b) independent on the angular momentum of the entrance channel, respectively. The later assumption is in better agreement with the presented data. 相似文献
139.
K. Yuyama T. Sugiyama T. Asahi S. Ryo I. Oh H. Masuhara 《Applied Physics A: Materials Science & Processing》2010,101(4):591-596
Quinacridone nanoparticles with a mean size of about 200 nm are successfully prepared using nanosecond near-infrared (NIR)
laser ablation of its microcrystalline powders in heavy water. The absorption spectra of the formed colloidal solutions depend
on the excitation wavelengths, which is eventually ascribed to number and energy of absorbed photons. β-carotene has low photostability and is easily decomposed upon UV/VIS laser ablation of its solid, while its nanoparticles
are prepared utilizing this NIR laser ablation technique. The advantage of nanoparticle preparation by NIR laser ablation
is discussed. 相似文献
140.
Takashi Arima Shigeru Taniguchi Tommaso Ruggeri Masaru Sugiyama 《Physics letters. A》2013,377(34-36):2136-2140
We show that, in the theory of extended thermodynamics, rarefied monatomic gases can be identified as a singular limit of rarefied polyatomic gases. Under naturally conditioned initial data we prove that the system of 14 field equations for polyatomic gases in the limit has the same solutions as those of the system of 13 field equations for monatomic gases where there exists no dynamic pressure. We study two illustrative examples in the process of the limit, that is, the linear waves and the shock waves in order to grasp the asymptotic behavior of the physical quantities, in particular, of the dynamic pressure. 相似文献