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991.
利用超高真空扫描隧道显微镜(UHV-STM)和有机分子束沉积(OMBD)方法研究了全氟并五苯(perfluoropentancene,PFP)分子在半金属Ga表面的吸附和两维自组装. 在低覆盖度下单个PFP分子在Ga表面上表现出很高的迁移性. 在1分子单层(monolayer, ML)时PFP分子发生二聚化并在 Ga 表面上无序排列. 轻度热退火可导致PFP两维自组装: 二聚体排列为高度有序的一维分子带阵列, 带中 PFP二聚体排列为砖墙(brick wall)结构. 在高分辨 STM图中, PFP分子两端出现亮暗相反的圆形突起, 并且相邻分子的亮暗极性相反, 表明PFP分子带有电偶极矩, PFP二聚体带有电四极矩. 因此, PFP分子二聚体的形成机制可唯像解释为反向电偶极矩之间的静电吸引作用; 二聚体的砖墙排列结构可归结为同向电四极矩之间的静电排斥作用. 相似文献
992.
Adi Rahwanto Yoshiro Matsuo Norihiko Nishizawa Toshio Goto Masakazu Mori Kazuo Yamane 《Optical Review》1999,6(4):355-358
The phase noise and the amplitude noise of optical pulses from the amplitude modulated harmonically mode-locked (AM-HML) Er-doped fiber (EDF) ring laser was investigated by measuring the power spectra of the optical pulses. The root mean square (RMS) timing jitter and the RMS amplitude noise are 1.26 ps and 2.5% (500 Hz-50 kHz), respectively, when the pulse repetition frequency is 1.58 GHz. They are smaller than those in conventional harmonically mode-locked EDF ring lasers. 相似文献
993.
Thermodynamically and kinetically stabilized asymmetric diaryltelluronium imides were synthesized and optically resolved into their enantiomers on an optically active column using medium‐pressure column chromatography. The relationship between the absolute configuration and the optical properties of the chiral telluronium imides was clarified. The mechanism of the racemization, which involves the formation of telluroxides by the hydrolysis of the telluronium imides, was proposed. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:523–529, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10185 相似文献
994.
995.
We have investigated both experimentally and numerically the characteristics of wavelength tunable femtosecond soliton pulse generation using a pulse width variable fiber laser and two different types of polarization maintaining fibers. The generated soliton shows the feature of the pulsewidth becoming almost constant at - 250 fs under any conditions of the pump pulse for 220m fiber. High conversion efficiency from pump pulse to a generated soliton pulse accounting for as much as 73% can be obtained. This efficiency decreases with increase in the input power or wavelength shift. A superior conversion efficiency and broad wavelength shift can be obtained by using a more shortened pump pulse. In the numerical calculations, it is predicted that under a condition of constant power of pump pulse, the maximum wavelength shift is achieved when the soliton number N is -1.4. The difference of mode field diameter and the group velocity dispersion (GVD) coefficient β2 affect the wavelength shift and conversion efficiency. Using the fiber with small mode field diameter and small absolute value of GVD coefficient β2, a high conversion efficiency and large wavelength shift can be obtained. 相似文献
996.
Fuminori Saito Naoki Suzuki Yoshiko Itoh Akira Goto Ichiro Fujiwara Toshikazu Kurihara Ren Iwata Yasuyuki Nagashima Toshio Hyodo 《Radiation Physics and Chemistry》2000,58(5-6):755-757
A system which supplies an intense 18F (half life 110 min) positron source produced by an AVF cyclotron through 18O(p,n)18F reaction has been constructed. Produced 18F is transferred to a low background experiment hall through a capillary. It is electro-deposited on a graphite rod and used for a source of a slow positron beam. In the meantime the next batch of target 18O water is loaded and proton irradiation proceeds. This system makes it possible to perform continuous positron beam experiments using the 18F positron source. 相似文献
997.
Toshio Honda 《Annals of the Institute of Statistical Mathematics》2000,52(4):599-611
We estimate the marginal density function of a long-range dependent linear process by the kernel estimator. We assume the innovations are i.i.d. Then it is known that the term of the sample mean is dominant in the MISE of the kernel density estimator when the dependence is beyond some level which depends on the bandwidth and that the MISE has asymptotically the same form as for i.i.d. observations when the dependence is below the level. We call the latter the case where the dependence is not very strong and focus on it in this paper. We show that the asymptotic distribution of the kernel density estimator is the same as for i.i.d. observations and the effect of long-range dependence does not appear. In addition we describe some results for weakly dependent linear processes. 相似文献
998.
Kazuki Nomura Minami Ikezaki Chihiro Kataoka Saori Hori Toshio Aoki Takashi Kuribayashi 《高压研究》2019,39(2):301-312
ABSTRACTDraft (non-pasteurized) sake typically has a fresh flavor, but usually has to be consumed as soon as possible because of its short shelf life due to the potential for over-fermentation by residual yeast. In contrast, thermally pasteurized sake has a long shelf life, but the fresh flavor is lost during heat sterilization. High hydrostatic pressure (HHP) treatment can be used as a non-thermal pasteurization process while maintaining the characteristics of a draft sake. We evaluated the HHP inactivation behavior of sake yeast for the application of HHP pasteurization as an alternative to thermal pasteurization. The results showed complete pasteurization of sake yeast in the draft sake by HHP treatment at 400?MPa for 10?min. The viable cell count in HHP-pasteurized sake was below the detection limit during storage at 10°C for 3 months. Thus, we have established a HHP pasteurization technology to prevent over-fermentation and succeeded in producing a prototype of HHP-sparkling-cloudy sake, which we have designated AWANAMA. 相似文献
999.
1000.
Shigeyuki Yamada Dr. Kanoko Shimoji Toshio Takahashi Tsutomu Konno Prof. Dr. Takashi Ishihara Prof. Dr. 《化学:亚洲杂志》2010,5(8):1846-1853
Treatment of trifluorovinyl‐ or pentafluoropropen‐1‐yl sulfone or sulfoxide, which are easily prepared from commercially available 1,2‐dibromofluoroalkanes, with various organocuprates affords substitution or β‐reduction products in good to excellent yields through an addition–elimination reaction sequence. 相似文献