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971.
M. N. Sondermann K. N. Suzuki E. C. Machado W. Machado L. F. Bellido R. T. Lopes A. V. B. Bellido 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):429-434
The biological activity influence on the mangrove sediment capacity to remove 65Zn and 109Cd from tidal water was evaluated in a site chronically polluted. Benthic Activity Indexes (BAI), corresponding to relative estimates of biological impact on radiotracer accumulation, were higher for 109Cd (~?38%) than for 65Zn (~?10%) in the top centimetre of sediment. However, BAI exceeded 96% for deeper sediment layers. This apparent decrease in radiotracer diffusion into deep sediments through biological activity inhibition is stronger than reported for much less polluted mangrove nearby, suggesting that benthic organisms tolerant of chronic metal pollution may affect metal sorption mechanisms. 相似文献
972.
Frontispiece: Docking Strategy To Construct Thermostable,Single‐Crystalline,Hydrogen‐Bonded Organic Framework with High Surface Area 下载免费PDF全文
973.
Hiroshi Suzuki 《Journal of Algebraic Combinatorics》1998,7(2):181-196
It is well known that an association scheme
with
has at most two P-polynomial structures. The parametrical condition for an association scheme to have two P-polynomial structures is also known. In this paper, we give a similar result for Q-polynomial association schemes. In fact, if
, then we obtain exactly the same parametrical conditions for the dual intersection numbers or Krein parameters. 相似文献
974.
Kecheng Xiao Hideo Ogawa Hideo Suzuki Yasuo Fukui 《International Journal of Infrared and Millimeter Waves》1998,19(1):15-31
A heterodyne receiver based on a 1/3 reduced height rectangular waveguide SIS mixer with two mechanical tuners has been built for astronomical observations of molecular transitions in the 230 GHz frequency band. The mixer used an untuned array (RnCj3, Rn70 ) of four Nb/AIOx/Nb tunnel junctions in series as a nonlinear mixing element. A reasonable balance between the input and output coupling efficiencies has been obtained by choosing the junction number N=4. The receiver exhibits DSB (Double Side Band) noise temperature around 50 K over a frequency range of more than 10 GHz centered at 230 GHz. The lowest system noise temperature of 38 K has been recorded at 232.5 GHz. Mainly by adjusting the subwaveguide backshort, the SSB (Single Side Band) operation with image rejection of 15 dB is obtained with the noise temperature as low as 50 K. In addition, the noise contribution from each receiver component has been studied further. The minimum SIS mixer noise temperature is estimated as 15 K, pretty close to the quantum limit v/k11 K at 230 GHz. It is believed that the receiver noise temperatures presented are the lowest yet reported for a 230 GHz receiver using untuned junctions. 相似文献
975.
C. Paal E. Weidenkaff E. Fischer U. Suzuki W. Traube A. Biltz St. W. Collins J. Litzendorff M. Busch G. Lunge E. Berl L. H. Ingham H. E. Patten A. Robinson E. Pozzi-Escot R. Bensemann J. Meisenheimer F. Heim F. Raschig G. Maderna G. Cofetti K. Farnsteiner W. Stüber G. Mehrtens A. Ganghofer und O. Köpke 《Fresenius' Journal of Analytical Chemistry》1911,50(7):454-463
Ohne Zusammenfassung 相似文献
976.
The structure of liquid Sb1-xSex alloys with x = 0.5, 0.6 and 0.7 was investigated in the temperature range of 600–800°C. The neutron diffraction measurements were carried out by using the high intensity total (HIT) scattering spectrometer of the booster synchrotron utilization facility (BSF) at the National Laboratory for High Energy Physics. A prepeak is observed in the structure factor for these three alloys. It suggests that the medium-range order stillo remains melting for liquid Sb1-xSex alloys, with x = 0.5, 0.6 and 0.7. The structure factor liquid Sb2Se3 alloys shows no appreciable temperature variation. For liquid Sb0.5Se0.5 alloy, the intensity of the prepeak exhibits an apparent decrease in the temperature range in which the non-metal-metal transition occurs. The non-metal-metal transition in liquid Sb---Se alloys is due to the change in the medium range structure. 相似文献
977.
Polycarbosilane (PC) is a precursor which is converted to SixC1−x fibers by pyrolysis in an inert gas atmosphere. The changes in the atomic vibrational spectrum during the conversion process from PC to SixC1−x have been examined by means of inelastic neutron scattering (INS) and infrared absorption (IR). The existence of transverse-optical(TO)- and longitudinal-optical(LO)-like phonon modes due to amorphous SiC clusters was established in the original and pyrolyzed PC by INS measurements. After pyrolyzing at 700–800°C, these modes appear distinctly around 730 and 930 cm−1, respectively, in the INS spectra. Pyrolysis at 1000°C makes these TO- and LO-like phonon modes sharper. 相似文献
978.
Silica based hybrid materials, some containing zirconia, prepared by gamma-irradiation, were studied by positron annihilation lifetime (PAL) spectroscopy, in the temperature range of 30-370 K. One long-lived component was observed in group of samples without zirconia. The behavior of this component as a function of temperature resembles that for polymers. This is explained by the elastomer like structure of the samples and the excellent linking between the inorganic and organic networks. The average radius, R, of the free-volume holes was in the range 0.26-0.42 nm depending on the temperature. In the group of samples containing zirconia two long-lived components were observed. A model with three different free-volume holes was suggested to explain the PAL results. Small closed holes (R ∼ 0.26 nm) and large closed holes introduced by Zr (R ∼ 0.5 nm), the sizes of both holes not changing with the temperature, together with intermediate polymer-like free-volume holes - the same behavior as those present in samples not containing zirconia. 相似文献
979.
Mami Kurumada Hitoshi Suzuki Yuki Kimura Yoshio Saito Chihiro Kaito 《Journal of Crystal Growth》2003,250(3-4):444-449
Dynamics of crystallization of amorphous antimony-selenium film deposited on carbon substrate have been studied by the high-resolution transmission electron microscopy. The amorphous film was suddenly crystallized at 200°C by heating in vacuum. By the electron beam irradiation crystallization occurred at the focused electron beam region in the amorphous film. The growth process of crystallization by electron beam irradiation was recorded on a video image at the atomic resolution mode. The growth front of crystallization showed nano-concave and -convex shapes. The recrystallization with the different orientation at the first grown crystal have been found, and discussed as the influence of remaining antimony crystallites at the first crystallized film region. 相似文献
980.
Hayakawa I Ueda M Yamaura M Ikeda Y Suzuki Y Yoshizato K Kigoshi H 《Organic letters》2008,10(9):1859-1862
Second-generation total synthesis of haterumalide NA, a potent cytotoxic marine macrolide, was achieved by using B-alkyl Suzuki-Miyaura coupling and Nozaki-Hiyama-Kishi coupling as key steps (1.2% in 33 steps). Compared to our first-generation approach, the second-generation synthesis is much improved in the yield of key intermediate. 相似文献