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51.
A prism anamorphic system for Gaussian beam expander 总被引:1,自引:0,他引:1
T. Kasuya T. Suzuki K. Shimoda 《Applied Physics A: Materials Science & Processing》1978,17(2):131-136
Basic properties are given of the prism anamorphic expander of a Gaussian beam composed of a couple of prisms in tandem. Its
shorter overall length for a given expansion, relative ease of optical adjustment, a sharp selection of polarization component,
and rather small inclusive dispersion make it an excellent beam expander in a specific laser cavity. The design principle
is presented of the prism system with a grating for an anastigmatic optical resonator for a dye laser of narrow linewidth
and of short pulse duration. 相似文献
52.
Kyoko Koizumi Yasuyo Okada Shizuyo Horiyama Toshiko Utamura Tadashi Higashiura Masahiro Ikeda 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):891-899
Cyclosophoraoses (CySs) are unbranched cyclic (12)--D-glucans produced by many strains ofAgrobacterium andRhizobium. Pure CyS-A, the group member having the smallest molecular size (degree of polymerization 17), was efficiently prepared by liquid chromatography using charcoal and ODS columns from the culture fluid of the mutant strain RA-12 fromR. phaseoli AHU 1133. The complex-forming ability of CyS-A was estimated from its enhancement of the solubilities of slightly soluble guest molecules in water using methods [I], [II], and [III]. In [I], an aqueous solution of CyS-A was shaken with the guest molecule, while, in [II], it was shaken with an acetone solution of the guest compound. In method [III], freeze-dried CyS-A powder was stirred with an acetone solution of the guest compound. The CyS-A cavity is thought to be able to accommodate three-dimensionally extended guest molecules,e.g., indomethacin. Method [II] was the best for obtaining CyS-A inclusion complexes, while method [III] would be recommended if the guest molecule is labile in the presence of water. Crystalline CyS-A inclusion complexes have not been obtained, but CyS-A complexes are expected to greatly enhance the solubilities of slightly soluble or insoluble guest molecules in water, because CyS-A is much more soluble than -cyclodextrin. Method [II] or [III] may afford a useful means of obtaining oily drug,e. g., vitamin E and K1, in an amorphous state. 相似文献
53.
Sharma HR Fournée V Shimoda M Ross AR Lograsso TA Tsai AP Yamamoto A 《Physical review letters》2004,93(16):165502
Based on scanning tunneling microscopy of the fivefold surface of the icosahedral Al-Cu-Fe quasicrystal and the refined structure model of the isostructural i-Al-Pd-Mn, we present evidence that the surface corresponds to bulk truncations at the positions where blocks of atomic layers are separated by larger interlayer spacings (gaps). Both step-height distribution and high resolution scanning tunneling microscopy images on terraces reveal bulk truncations at larger gaps. 相似文献
54.
Characteristics and role of Al oxide (Al-O) films used as catalyst-support layer for vertical growth of single-walled carbon nanotubes (SWCNTs) were studied. EB-deposited Al films (20 nm) were thermally oxidized at 400 °C (10 min, static air) to produce the most appropriate surface structure of Al-O. Al-O catalyst-support layers were characterized using various analytical measurements, i.e., atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and spectroscopy ellipsometry (SE). The thermally oxidized Al-O has a highly roughened surface, and also has the most suitable surface chemical states compared to other type of Al-O support layers. We suggest that the surface of thermally oxidized Al-O characterized in this work enhanced Co catalyst activity to promote the vertically aligned SWCNT growth. 相似文献
55.
Regina Sibgatullina Katsumasa Fujiki Takefumi Murase Takahiro Yamamoto Taiji Shimoda Almira Kurbangalieva Katsunori Tanaka 《Tetrahedron letters》2017,58(20):1929-1933
One pot double click strategy containing strain-promoted click-reaction followed by 6π-azaelectrocyclization (RIKEN click reaction) has worked well in the synthesis of multivalent homogeneous and heterogeneous N-glycoalbumins. We have slightly changed the structure of linker unsaturated aldehyde used in this method. As a result it can be easily synthesized from commercially available material and furthermore, the enhancement of its reactivity towards both click-reactions was observed. The data described in this Communications facilitate the usage of the double click strategy as a general method for the synthesis of a variety of neo-N-glycoproteins. 相似文献
56.
T. Shimoda K. Tajiri K. Kura A. Odahara M. Suga Y. Hirayama N. Imai H. Miyatake M. Pearson C. D. P. Levy K. P. Jackson R. Legillon C. Petrache T. Fukuchi N. Hamatani T. Hori M. Kazato Y. Kenmoku T. Masue H. Nishibata T. Suzuki A. Takashima R. Yokoyama 《Hyperfine Interactions》2014,225(1-3):183-191
Spin-polarized radioactive nuclear beams at TRIUMF enable a new spectroscopic method which efficiently assigns spins and parities of the daughter levels by taking advantage of the asymmetric β-decay of the polarized parent nucleus. This method was successfully applied to structure studies of 29Mg and 30Mg in connection with the physics of the “island of inversion”. In 29Mg, two low-lying levels with intruder configuration were assigned. In 30Mg, coexistence of spherical shape, prolate shape and γ-collectivity was strongly suggested. 相似文献
57.
Theoretical considerations are given on the sensitivity of laser spectrometers in which the molecular transition is observed
by a photoelectric detector, a photoconductive detector, or a diode. It is shown that the single-pass absorption spectrometer
has extremely high sensitivity at a relatively high gas pressure and with optimum laser power. The holeburning spectrometer
is less sensitive, though in offers much higher resolution of the homogeneous width at a low gas pressure. The nonlinear fluorescence
method is characterized by both high resolution and high sensitivity, provided the fluorescence from the laser-excited level
can be observed.
The minimum detectable number of absorbing molecules is calculated to be 102 to 106 depending on the parameters of the spectrometer. Thus a concentration of absorbing molecules lower than 10−12 is expected to be detectable in some cases. 相似文献
58.
Nobumoto?NagasawaEmail author Shugo?Ikeda Aiko?Shimoda Takeshi?Waki Yoshikazu?Tabata Hiroyuki?Nakamura Hisao?Kobayashi 《Hyperfine Interactions》2016,237(1):39
The 57Fe Mössbauer spectra of the single crystalline and the finely ground Sr1?x La x Fe12?y Co y O19 (x = 0 : y = 0, x = 0.192 : y = 0.152 and x = 0.456 : y = 0.225) samples have been measured to investigate the La-Co substitution effects. All observed spectra at 150 K were well fitted using the five subspectra which correspond to the five crystallographical nonequivalent Fe sites in the M-type hexaferrite, indicating that the valence changes to Fe2+ ions in the Fe3+ ions were not observed in our Sr1?x La x Fe12?y Co y O19 samples. In SrFe12O19, the relative absorption intensities in the five subspectra show the large anisotropies in the recoilless fractions at the five Fe sites whereas these anisotropies were not observed in Sr0.544La0.456Fe11.775Co0.225O19. These results indicate the chemical compositional dependence on the anisotropies of the recoilless fractions at the five Fe sites. The substitution of a Co2+ ion for the Fe3+ ion changes the center shifts of the Fe3+ ions near the Co2+ ion by the perturbation of the Fe-O-Co hybridizations. Therefore, the Co2+ ions occupy the 4f 1 and the 4f 2 sites due to the chemical compositional dependences of the refined magnetic hyperfine field and center shifts of the Fe3+ ions. 相似文献
59.
60.
Yousuke Yamaoka Motoki Ueda Tohru Yamashita Kazuma Shimoda Ken-ichi Yamada Kiyosei Takasu 《Tetrahedron letters》2017,58(30):2944-2947
Cyclic ketene silyl acetals were utilized for [2 + 2] cycloaddition with propiolates to prevent an undesired electrocyclic ring opening reaction. Trimethylaluminum catalyzed this cycloaddition to afford the cyclobutene derivatives in high yields. The advantage of this reaction was highlighted by the successful application of β-substituted propiolates to afford the multi-substituted cyclobutenes. Furthermore, we applied this methodology to the late stage functionalization of natural product artemisinin. 相似文献