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31.
A laser terahertz-emission microscope (LTEM) system is proposed and developed for inspecting electrical faults in integrated circuits (IC). We test a commercial operational amplifier while the system is operating. Two-dimensional terahertz-emission images of the IC chip are clearly observed while the chip is scanned with a femtosecond laser. When one of the interconnection lines is cut, the damaged chip has a LTEM image different from that of normal chips. The results indicate that the LTEM system is a potential tool for IC inspection. 相似文献
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Zegers RG Abend H Akimune H van den Berg AM Fujimura H Fujita H Fujita Y Fujiwara M Galès S Hara K Harakeh MN Ishikawa T Kawabata T Kawase K Mibe T Nakanishi K Nakayama S Toyokawa H Uchida M Yamagata T Yamasaki K Yosoi M 《Physical review letters》2003,90(20):202501
The excitation and subsequent proton decay of the isovector spin-flip giant monopole resonance (IVSGMR) is studied via the 208Pb(3He,t) reaction at 410 MeV. In the inclusive spectrum (60+/-5)% of the non-energy-weighted sum-rule strength for this 2 variant Planck's over 2h omega resonance was found in the region 29相似文献
33.
Mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1), obtained from the reaction of N-acyl-N-alkylglycines (2) with trifluoroacetic anhydride, react with ammonia to give 4-trifluoromethyl-3,4-dihydroimidazoles (3) in high yields. Dehydration of 3 gives 4-trifluoromethylimidazoles (4) in high yields. The novel ring transformation of 1 into 3 occurs via a regioselective attack of ammonia on the C-2 position of the ring. 相似文献
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Shin‐Ichi Yusa Shigeki Awa Masanori Ito Takeshi Kawase Tadao Takada Kenichi Nakashima Dian Liu Shigeru Yamago Yotaro Morishima 《Journal of polymer science. Part A, Polymer chemistry》2011,49(13):2761-2770
Water‐soluble diblock copolymer, poly(N‐isopropylacrylamide)‐block‐poly(N‐vinyl‐2‐pyrroridone) (PNIPAMm‐b‐PNVPn), was found to associate with fullerene (C60), and thus C60 can be solubilized in water. The 63C60/PNIPAMm‐b‐PNVPn micelle formed a core‐shell micelle‐like aggregate comprising a C60/PNVP hydrophobic core and a thermoresponsive PNIPAM shell. The C60‐containing polymer micelle formation and its thermoresponsive behavior were characterized using light scattering and 1H NMR techniques. The hydrodynamic radius (Rh) of the C60‐bound polymer micelle increased with increasing temperature, which was ascribed to the hydrophobic association between dehydrated PNIPAM shells above lower critical solution temperature (LCST). 1H NMR data suggest that the motion of the PNIPAM block is restricted above LCST due to the dehydration of the PNIPAM shell in water. The generation of singlet oxygen by photosensitization by the C60‐bound polymer micelle was confirmed from photooxidation of 9,10‐anthracenedipropionic acid. Furthermore, DNA was found to be cleaved by visible light irradiation in the presence of the C60‐bound polymer micelle. Therefore, there may be a hope for a pharmaceutical application of the C60‐bound polymer micelle to cancer photodynamic therapy. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011. 相似文献
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Pumping dye-doped organic polymer by interference pattern of a frequency-doubled Nd:YAG 532 nm laser to induce a periodic gain-structure and confining it within a stable optical resonator, the oscillation output can be effectively enhanced in comparison with either that of uniform irradiation, i.e., pumping, or of distributed feedback (DFB) operation, and the oscillation wavelength becomes tunable by adjusting the period of the interference pattern. Using Rhodamine-B as a dopant over the range from 200 to 1000 ppm, the oscillation output was enhanced by - 10 dB, which was larger than the output of the uniform irradiation and was - 30% greater than the DFB scheme. Moreover, changing the period of the interference pattern by adjusting the setting angle of the Koster prism enables us to vary the oscillation wavelength around 600 nm. 相似文献
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Takashi Kumagai Tomohiro Anki Akihito Konishi Hiroyuki Kurata Kenta Katsumoto Takeshi Kawase 《Tetrahedron》2010,66(46):8968-8973
Carboxylic acids were heated at 150 °C in DMF in the presence of 1.25 equiv of thionyl chloride to give corresponding N,N-dimethylamides in good yields. Tandem chlorination and amidation reactions occurred in the one-pot procedure. Dicarboxylic acids needed prolonged reaction time to produce bisamides in good yields. Some benzamides were efficiently converted into corresponding 1,2-diaryl-1,2-diketones (benzils) under acyloin condensation conditions in the presence of 4,4′-di-tert-butylbiphenyl (DBB) in THF. Ultrasonic irradiation effectively accelerates the reaction, but it is not critical. However, the presence of DBB is fatal to the reaction. Although a few synthetic methods for benzils from benzoic acids have been reported so far, this method is one of the most convenient and highly reproducible procedures. 相似文献
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