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81.
Tetsuo Irifune Chiaki Ueda Shohei Ohshita Hiroaki Ohfuji Takehiro Kunimoto Toru Shinmei 《高压研究》2020,40(1):96-106
ABSTRACTNano-polycrystalline diamond (NPD) with various grain sizes has been synthesized from glassy carbon at pressures 15–25?GPa and temperatures 1700–2300°C using multianvil apparatus. The minimum temperature for the synthesis of pure NPD, below which a small amount of compressed graphite was formed, significantly increased with pressure from ~1700°C at 15?GPa to ~1900°C at 25?GPa. The NPD having grain sizes less than ~50?nm was synthesized at temperatures below ~2000°C at 15?GPa and ~2300°C at 25?GPa, above which significant grain growth was observed. The grain size of NPD decreases with increasing pressure and decreasing temperature, and the pure NPD with grain sizes less than 10?nm is obtained in a limited temperature range around 1800–2000°C, depending on pressure. The pure NPD from glassy carbon is highly transparent and exhibits a granular nano-texture, whose grain size is tunable by selecting adequate pressure and temperature conditions. 相似文献
82.
Pairwise linear discriminant analysis can be regarded as a process to generate rankings of the populations. But in general, not all rankings are generated. We give a characterization of generated rankings. We also derive some basic properties of this model. 相似文献
83.
Boris?ShapiroEmail author Kouichi?Takemura Milo??Tater 《Communications in Mathematical Physics》2012,311(2):277-300
The well-known Heun equation has the form
ll{Q(z)\frac d2dz2+P(z)\fracddz+V(z)}S(z)=0,\begin{array}{ll}\left\{Q(z)\frac {d^2}{dz^2}+P(z)\frac{d}{dz}+V(z)\right\}S(z)=0,\end{array} 相似文献
84.
85.
Wen Piao Satoru Tsuda Dr. Yuji Tanaka Dr. Satoshi Maeda Dr. Fengyi Liu Shodai Takahashi Yu Kushida Dr. Toru Komatsu Dr. Tasuku Ueno Dr. Takuya Terai Prof. Toru Nakazawa Prof. Masanobu Uchiyama Prof. Keiji Morokuma Prof. Tetsuo Nagano Dr. Kenjiro Hanaoka 《Angewandte Chemie (International ed. in English)》2013,52(49):13028-13032
86.
87.
Sato S Komoto T Kanamaru Y Kawamoto N Okada T Kaiho T Mogi K Morimoto S Umehara N Koda T Miyashita A Sakamoto T Niino Y Oka T 《Chemical & pharmaceutical bulletin》2002,50(2):292-297
New muq-opioid receptor (MOR) agonists containing 4-hydroxypiperidine, piperidine and piperazine moieties were synthesized and evaluated to find a peripheral opioid analgesic. Among the synthesized compounds, 12-[1-[3-(N,N-dimethylcarbamoyl)-3,3-diphenylpropyl]-4-hydroxypiperidin-4-yl]phenoxy]acetic acid (8: SS620) having phenoxyacetic acid and 4-hydroxypiperidine moieties showed the highest agonist potency on the MOR in an isolated guinea-pig ileum preparation, and it also had selectivity to the human MOR expressed in Chinese hamster ovary (CHO)-K1 cells compared with the same types of delta- and kappa-opioid receptors (DOR and KOR). In addition, compound 8 showed a 10 times more potent MOR agonist activity than loperamide. Furthermore, compound 8 showed a peripheral analgesic activity in vivo screening on rat. 相似文献
88.
[reaction: see text] A series of oligo(octithienylene-diethynylene)s alternately composed of octithiophene and diacetylene units have been prepared by a random Eglinton coupling reaction among mono- and diethynyloctithiophenes. The largest compound isolated in the oligomeric series is comprised of twelve octithiophene units and eleven diacetylene units, and its molecular length reaches ca. 43 nm, which is the longest among single-component conjugated nanomolecules. 相似文献
89.
Kon N Takemura H Otsuka K Tanoue K Nakashima S Yasutake M Tani K Kimoto J Shinmyozu T Inazu T 《The Journal of organic chemistry》2000,65(12):3708-3715
Macropolycyclic cage compounds were synthesized by a direct reaction between diamines and bis(bromomethyl) compounds. The procedure for constructing the polycyclic cage structure is simple and straightforward. The macropolycyclic compounds obtainable from this cyclization procedure are three-dimensional cage compounds, and any other isomers were not obtained except for two examples. Benzene, pyridine, and aliphatic units could be introduced into the cage structure. The macrocycles that have strong cation affinity were obtained as their potassium complexes. 相似文献
90.
Cyril T. Langlois Tetsuo Oikawa Pascale Bayle-Guillemaud Christian Ricolleau 《Journal of nanoparticle research》2008,10(6):997-1007
CuAg core–shell nanoparticles are synthesized by ultra-high vacuum thermal evaporation. We show on this system how the Energy-Filtered
Transmission Electron Microscopy (EFTEM) technique allows one to improve the characterization by precisely pointing out the
formation of core–shell arrangements in bimetallic nanoparticle assemblies. A criterion to measure the shell thickness from
EFTEM images on unique core–shell nanoparticles is defined, that can be used for core–shell nanoparticles of any sizes, with
shell thicknesses over 1 nm. It is based on the intensity variation along a line drawn across a core–shell nanoparticle on
a EFTEM image. This criterion has been validated by a close comparison of the shell thickness measurements performed in this
work and the ones obtained by acoustic micro-Raman spectroscopy. Using this criterion, we report a strong correlation between
the size of the Cu cores and the formation of the core–shell arrangements in the nanoparticle assembly studied in this work.
The influence of the Cu core shape is also evidenced. The characterisation of such systems using High Resolution TEM (HRTEM)
is also discussed. 相似文献
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