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41.
V. Slugeň J. Lipka I. Tóth J. Haščík M. Lehota I. Smieško 《Czechoslovak Journal of Physics》2001,51(9):909-916
Magnetic phases of corrosion products from nuclear power plant WWER-440 (Jaslovské Bohunice) steam generators and secondary circuit pipes were investigated using transmission Mössbauer spectroscopy technique. The main components of secondary circuit’s corrosion products are magnetite (Fe3O4) and hematite (α-Fe2O3) in different ratios. The results can be used for optimal control and maintenance of WWER-440 nuclear reactors as well as for optimisation of water chemistry regime. 相似文献
42.
Cao Thi Vi Ba Ha Huy Bang Dang Van Soa 《International Journal of Theoretical Physics》2003,42(8):1781-1786
We propose commutation relations for a single mode -deformed para-Bose oscillator. In this new deformation of para-Bose statistics the distribution function has the same form as in the para-Bose statistics. Furthermore, we show analogies between the coherent states of -deformed and q-deformed para-Bose statistics. 相似文献
43.
巯基胺型螯合树脂经烷氧基环硫丙烷和二烷基胺基环硫丙烷改性后。合成了一系列新的螫合树脂.这些树脂与原树脂相比,对贵金属离子的吸附性能有一定的改善.特别是用二烷基胺基环硫丙烷改性后的树脂,效果更为明显.还讨论了树脂结构与吸附性能之间的关系. 相似文献
44.
Zhang LM Zhang ZP Li J Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Asano Y Aushev T Bahinipati S Bakich AM Balagura V Barbero M Bay A Bedny I Belous K Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Ha HC Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M 《Physical review letters》2006,96(15):151801
We report the results of a search for D0-D0 mixing in D0 --> K+ pi- decays based on 400 fb(-1) of data accumulated by the Belle detector at KEKB. Both assuming CP conservation and allowing for CP violation, we fit the decay-time distribution for the mixing parameters x and y, as well as for the parameter R(D), the ratio of doubly Cabibbo-suppressed decays to Cabibbo-favored decays. The 95% confidence level region in the (x'2,y') plane is obtained using a frequentist method. Assuming CP conservation, we find x'2 < 0.72 x 10(-3) and -9.9 x 10(-3) < y' < 6.8 x 10(-3) at the 95% confidence level; these are the most stringent constraints on the mixing parameters to date. The no-mixing point (0,0) has a confidence level of 3.9%. Assuming no mixing, we measure R(D) = (0.377 +/- 0.008 +/- 0.005)%. 相似文献
45.
For the first time to our knowledge, pulse-amplitude equalization of rational-harmonically mode-locked fiber ring laser pulses has been experimentally demonstrated using a polarization-maintaining laser resonator without any additional device. The pulse-amplitude distribution of the laser pulses was controlled by the modulator driving power, and stable pulse-amplitude-equalized pulses with repetition rates of 20, 30, and 40 GHz have been obtained in the linear region of the modulator. 相似文献
46.
Wang XL Yuan CZ Shen CP Wang P Adachi I Aihara H Arinstein K Aushev T Bakich AM Barberio E Bedny I Bhardwaj V Bitenc U Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chen A Chen KF Cheon BG Chiang CC Chistov R Cho IS Choi SK Choi Y Dalseno J Danilov M Dash M Drutskoy A Eidelman S Epifanov D Gabyshev N Go A Gokhroo G Ha H Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou WS Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki Y Kah DH Kang JH Kawai H Kawasaki T 《Physical review letters》2007,99(14):142002
The cross section for e+ e- --> pi+ pi- psi(2S) between threshold and sqrt[s]=5.5 GeV is measured using 673 fb(-1) of data on and off the Upsilon(4S) resonance collected with the Belle detector at KEKB. Two resonant structures are observed in the pi+ pi- psi(2S) invariant-mass distribution, one at 4361 +/- 9 +/- 9 MeV/c2 with a width of 74 +/- 15 +/- 10 MeV/c2, and another at 4664 +/- 11 +/- 5 MeV/c2 with a width of 48 +/- 15 +/- 3 MeV/c2, if the mass spectrum is parametrized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states. 相似文献
47.
48.
A curtain-type airbag is a safety device designed to protect passengers from the side collisions of a car. The curtain-type
airbag system consists of an inflator, a fill-hose, and a curtain-airbag. The fill-hose is a passageway and distributor of
the exploded gases from the inflator to the airbag through vent-holes. Although the design of vent-holes is important for
proper deployment of the airbag, it is very difficult to measure the exceedingly high speed flow issuing from the vent-holes
by using conventional measurement methods. In this study, we employed a dynamic PIV technique to measure the temporal evolution
of instantaneous velocity fields of the flow ejecting from the vent-holes. From the velocity field data measured at a frame
rate of 2000 fps, the temporal variation of the volume flux from vent-holes was also evaluated for the diagnosis of airbag
performance. The flows ejecting from the vent-holes showed high velocity fluctuations, and the maximum velocity was about
480 m/s. The instantaneous velocity fields in the initial stage showed a swaying motion of a high-speed jet. The accumulated
volume flux from the vent-holes was also compared at each vent-hole region. 相似文献
49.
High-purity ZnO nanowires have been synthesized on Si substrates without the presence of a catalyst at 600 °C by a simple thermal vapor technique. Photoluminescence (PL) spectra of the annealed samples at 900 °C under oxygen and argon gases have been investigated. After O2 or Ar annealing, the PL visible-emission intensity that is related to intrinsic defects (oxygen vacancies) is greatly reduced compared with as-grown ZnO nanowires because the oxygen-gas ions or oxygen interstitials diffuse into the oxygen vacancies during annealing process. The blue-band peak of the O2- or Ar-annealed ZnO naonowires is also smaller than the green-band peak in the visible broadband because of the reduction of oxygen vacancies. Therefore, the main intrinsic defects (oxygen vacancies) of as-grown ZnO nanowires can be reduced by O2 or Ar annealing, which is an important procedure for the development of advanced optoelectronic ZnO nanowire devices. 相似文献
50.
Nida Iqbal Rabia NazirAnila Asif Aqif Anwar ChaudhryMuhammad Akram Goh Yi FanAftab Akram Rashid AminSung Ha Park Rafaqat Hussain 《Current Applied Physics》2012,12(3):755-759
Polyvinyl alcohol (PVA) coated hydroxyapatite was deposited onto a 316L stainless steel substrate by electrophoretic deposition. Deposition was carried out in a methanol suspension at pH 5.5 using a graphite rod as an anode. Parameters such as PVA concentration, deposition voltage and time were optimized to achieve a homogeneous, crack-free adhesive coating. Techniques such as X-ray diffraction and Fourier transform infrared spectroscopy were used to study the phase composition of the coated materials and the stability of hydroxyapatite in the presence of PVA. 相似文献