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981.
Separation of Linear and Branched Alkanes Using Host–Guest Complexation of Cyclic and Branched Alkane Vapors by Crystal State Pillar[6]arene 下载免费PDF全文
Prof. Tomoki Ogoshi Kazuki Saito Ryuta Sueto Ryosuke Kojima Yukie Hamada Prof. Shigehisa Akine Dr. Adhitya Mangala Putra Moeljadi Dr. Hajime Hirao Dr. Takahiro Kakuta Prof. Tada‐aki Yamagishi 《Angewandte Chemie (International ed. in English)》2018,57(6):1592-1595
Activated crystals of pillar[6]arene produced by removing the solvent upon heating were able to take up branched and cyclic alkane vapors as a consequence of their gate‐opening behavior. The uptake of branched and cyclic alkane vapors by the activated crystals of pillar[6]arene induced a crystal transformation to form one‐dimensional channel structures. However, the activated crystals of pillar[6]arene hardly took up linear alkane vapors because the cavity size of pillar[6]arene is too large to form stable complexes with linear alkanes. This shape‐selective uptake behavior of pillar[6]arene was further utilized for improving the research octane number of an alkane mixture of isooctane and n‐heptane: interestingly, the research octane number was dramatically improved from a low research octane number (17 %) to a high research octane number (>99 %) using the activated crystals of pillar[6]arene. 相似文献
982.
983.
984.
Nakanishi T Yamakawa N Asahi T Osaka T Ohtani B Uosaki K 《Journal of the American Chemical Society》2002,124(5):740-741
Self-assembled monolayer of atropisomeric compound, 1,1'-binaphthalene-2,2'-dithiol (BNSH), provides a field for chiral discrimination. The two-dimensional chiral arrangement with screw-like units, each of which is composed of three BNSH molecules, plays an important role in the enantioselectivity of adsorption of phenylalanine, as revealed by a quartz crystal microbalance technique. 相似文献
985.
986.
T. Nakanishi M. Satoh M. Takei A. Ishikawa M. Murata M. Dairyoh S. Higuchi 《Journal of Radioanalytical and Nuclear Chemistry》1990,138(2):321-330
Plutonium 239,240 was measured using large-volume water samples from the North Pacific and its adjacent seas. The vertical profiles of239,240Pu show features that are similar to those reported in earlier papers with a subsurface maxima of around 660 m and a significant concentration increase in the North Pacific bottom waters. It became evident that the239,240Pu concentration in deep bottom water is proportional to the inventory of the nuclides in the overlying water column and that the appearent distribution ratios of the nuclides between deep-sea sediment and bottom water lie in a relatively narrow range of about 2×104 to 105, independent of sea area and warter depth. The latter implies that239,240Pu may follow a reversible-type partition process at a deep water/sediment interface. In order to substantiate this assumption, it is desirable to study the phenomenon for Pu as well as for other long-lived radionuclides, both artificial and natural. From this point of view, an analytical procedure for the successive determination of selected long-lived radionuclides was studied. 相似文献
987.
S Koikeda M Tamaru M Goto N Mori S Takada M Obinata Y Masamune Y Nakanishi 《Chemical & pharmaceutical bulletin》1989,37(4):1103-1105
The effect of a change in the concentration of c-myc protein on the expression of genes for two phosphoglycerate kinase isozymes was investigated. The steady state levels of messenger ribonucleic acids (mRNAs) for sperm-type and non-sperm-type proteins were determined by blot hybridization using the RNA of the mouse cell line 38-2 containing the inducible rat c-myc gene cultured under various conditions. Without induction the c-myc gene. mRNA for non-sperm-type protein was detected at a level that remained essentially constant during both activation and inactivation of the c-myc gene. mRNA for sperm-type protein was not detected in 38-2 cells cultured under any conditions used. Change in the amount of c-myc protein alone does not appear to bring about a switch of the expression of the two phosphoglycerate kinase genes during spermatogenesis in mouse testis. 相似文献
988.
989.
Artuso M Goldberg M He D Horwitz N Kennett R Mountain R Moneti GC Muheim F Mukhin Y Playfer S Rozen Y Stone S Thulasidas M Vasseur G Xing X Zhu G Bartelt J Csorna SE Egyed Z Jain V Kinoshita K Barish B Chadha M Chan S Cowen DF Eigen G Miller JS O'Grady C Urheim J Weinstein AJ Acosta D Athanas M Masek G Paar HP Sivertz M Gronberg J Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Qiao C Richman JD Ryd A Tajima H Sperka D Witherell MS Procario M Balest R Cho K Daoudi M Ford WT 《Physical review letters》1994,72(24):3762-3766
990.
Hironori Kaji Kazuki Nakanishi Naohiro Soga Tadashi Inoue Norio Nemoto 《Journal of Sol-Gel Science and Technology》1994,3(3):169-188
The investigation of phase separation processes induced by polymerization reactions of tetramethoxysilane (TMOS) was attempted by a time-resolved light scattering method for TMOS-formamide-water system under the acid-catalyzed condition. Since the early stage of the phase separation exhibits very fast kinetics and weak scattering intensity, the experimental set-up was designed so as to reduce the experimental error and to obtain higher time resolution by using a laser beam expander. For the gels whose morphologies are interconnected structure and aggregates of particles, it was experimentally found that the wavelength of the concentration fluctuation in the early stage of phase separation was time-independent and its amplitude grew exponentially with time. This suggests that these samples phase-separate by spinodal decomposition mechanism. In the later stages of phase separation, the coarsening process and the following structure-freezing process by gel-network formation were observed. 相似文献