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31.
Hidemitsu Aoki Makoto Hara Takuro Masuzumi Motaharu K. Mazumder Naoki Ooi Daisuke Watanabe Chiharu Kimura Takashi Sugino 《Applied Surface Science》2009,255(6):3719-3722
Cu electroplating is required for the fabrication of Cu/low-k interconnections. The permeation of a plating solution into low-k films during Cu electroplating is a serious challenge for 45-nm nodes and more complex devices. We investigated the influence of Cu electroplating solutions on boron carbon nitride (BCN) as a low-k film. After dipping it into a Cu electroplating solution that contained additives, the BCN film's hydrophilic surface changed to a hydrophobic surface, and the incorporation of water into the BCN film was suppressed by surfactant adsorption. Sulfuric residue was detected on the BCN sample by thermal desorption spectroscopy after treatment in the Cu electroplating solution with additives; however, it was found through electrical measurements that this solution did not affect the leakage current or the dielectric constant of the BCN film. We successfully fabricated an electroplating Cu layer on a BCN film with good adhesion, and we believe that this BCN film is a sufficiently useful material for Cu/BCN integration in LSI. 相似文献
32.
On the ‐boundedness of solution operator families of the generalized Stokes resolvent problem in an infinite layer 下载免费PDF全文
Hirokazu Saito 《Mathematical Methods in the Applied Sciences》2015,38(9):1888-1925
In this paper, we prove the ‐boundedness of solution operator families of the generalized Stokes resolvent problem in an infinite layer with resolvent parameter , where , and our boundary conditions are nonhomogeneous Neumann on upper boundary and Dirichlet on lower boundary. We want to emphasize that we can choose 0 < ? < π ∕ 2 and γ0 > 0 arbitrarily, although usual parabolic theorem tells us that we must choose a large γ0 > 0 for given 0 < ? < π ∕ 2. We also prove the maximal Lp ? Lq regularity theorem of the nonstationary Stokes problem as an application of the ‐boundedness. The key of our approach is to apply several technical lemmas to the exact solution formulas of a resolvent problem. The formulas are obtained through the solutions of the ODEs, in the Fourier space, driven by the partial Fourier transform with respect to tangential space variable . Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
33.
Esen S Schwartz AJ Adachi I Aihara H Arinstein K Aulchenko V Aushev T Aziz T Bakich AM Balagura V Barberio E Bay A Bischofberger M Bondar A Bozek A Bračko M Browder TE Chang MC Chang P Chen A Chen P Cheon BG Chiang CC Choi Y Dalseno J Dash M Doležal Z Drásal Z Drutskoy A Eidelman S Goldenzweig P Golob B Ha H Haba J Hara T Hayasaka K Higuchi T Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Inami K Itoh R Iwabuchi M Joshi NJ Julius T Kang JH Kawasaki T Kichimi H Kim HJ Kim HO Kim JH Kim YJ Kinoshita K 《Physical review letters》2010,105(20):201802
We have made the first observation of B(s)(0)→D(s)(*)+ D(s)(*)- decays using 23.6 fb(-1) of data recorded by the Belle experiment running on the Υ(5S) resonance. The branching fractions are measured to be B(B(s)(0)→D(s)+ D(s)-)=(1.03(-0.32-0.25)(+0.39+0.26))%, B(B(s)(0)→D(s)(*±) D(s)(?))=(2.75(-0.71)(+0.83)±0.69)%, and B(B(s)(0)→D(s)*+ D(s)*-)=(3.08(-1.04-0.86)(+1.22+0.85))%; the sum is B[B(s)(0)→D(s)(*)+ D(s)(*)-]=(6.85(-1.30-1.80)(+1.53+1.79))%. Assuming B(s)(0)→D(s)(*)+ D(s)(*)- saturates decays to CP-even final states, the branching fraction determines the ratio ΔΓ(s)/cosφ, where ΔΓ(s) is the difference in widths between the two B(s)-B(s) mass eigenstates, and φ is a CP-violating weak phase. Taking CP violation to be negligibly small, we obtain ΔΓ(s)/Γ(s)=0.147(-0.030)(+0.036)(stat)(-0.041)(+0.042)(syst), where Γ(s) is the mean decay width. 相似文献
34.
Suzuki M Husimi Y Komatsu H Suzuki K Douglas KT 《Journal of the American Chemical Society》2008,130(17):5720-5725
Fluorescent acceptors have been immobilized on nanoparticulate quantum dots (QDs), which serve in turn as their FRET donors. The broad excitation and narrow emission bands of QDs mark them as having excellent potential as donors for FRET and, in principle, differently colored QDs could be excited simultaneously. The present work describes the preparation and operation of FRET-based QD bioprobes individually able to detect the actions of protease, deoxyribonuclease, DNA polymerase, or changes in pH. In addition, two such QD-mounted biosensors were excited at a single wavelength, and shown to operate simultaneously and independently of each other in the same sample solution, allowing multiplex detection of the action of a protease, trypsin, in the presence of deoxyribonuclease. 相似文献
35.
Selective mono-deallylation of O,O'-diallylcatechols using 10% Pd/C was investigated to give the correspond-ing allylphenols. A similar reaction of 3-methylene-1,5-benzodioxepanes afforded O-methacryl catecohols. When substrates bearing various substituents on the benzene ring were subjected to the reaction, regioselective cleavage of an ether bond occurred at the side of para position to an electron-withdrawing group on the aromatic ring. On the other hand, an electron-donating group did not cause any selectivity. 相似文献
36.
The vibrational spectrum of thionyl fluoride, SOF2, has been reinvestigated by means of high resolution infrared and Raman spectroscopy. Substitution of oxygen-16 by oxygen-18 led to a definitive identification of those modes to which sulfur-oxygen motion makes a large contribution. The band structure of the sulfur-oxygen stretching vibration, which is obscured by Fermi resonance with a combination band in S16OF2, has been resolved in S18OF2. The experimental isotopic splittings are compared with those calculated by previous investigators. 相似文献
37.
C. E. Parker J. R. Perkins K. B. Tomer Y. Shida K. O’Hara M. Kono 《Journal of the American Society for Mass Spectrometry》1992,3(5):563-574
Nanoscale separation techniques, nanoscale packed capillary columns (75 μm id), and capillary zone electrophoresis (CZE), on-line with electrospray mass spectrometry (ESI/MS), were applied to the separation of a series of ten macrolide antibiotics. Both techniques use sub-microliter-per-minute flow rates through the analytical column and therefore require an electrospray probe that incorporates coaxial sheath flow. Positive ion electrospray mass spectra of these compounds yielded mainly protonated molecules. Fragmentation to yield structurally significant fragment ions was achieved by collision-induced dissociation (CID) at increased skimmer voltages. Separations were achieved using both techniques, with CZE/ESI/MS showing improved peak shapes and detection limits combined with faster analysis times. Nanoscale packed capillary columns provided better chromatographic resolution and was less susceptible to peak broadening caused by overloading of the analytes. 相似文献
38.
39.
Yoshio Iwakura Keikichi Uno Shigeyoshi Hara Shigeru Kurosawa 《Journal of polymer science. Part A, Polymer chemistry》1968,6(12):3381-3393
A new ring-opening reaction of 1,3,4-oxadiazole by methylating reagents was developed in fuming sulfuric acid or polyphosphoric acid and then, by applying this reaction to poly-p-phenylene-1,3,4-oxadiazole, a high molecular weight poly-N-methylterephthalylhydrazide was obtained. Various methylating reagents were investigated as ring-opening reagents. The degrees of ring-opening in polymers were estimated and related to the properties of the polymers. 相似文献
40.
Dr. Jun Nakamura Hidenori Yamashiro Sayaka Hayashi Mami Yamamoto Kenji Miura Dr. Shu Xu Prof. Dr. Takayuki Doi Dr. Hideki Maki Osamu Yoshida Prof. Dr. Hirokazu Arimoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(40):12681-12689
Covalently linked vancomycin dimers have attracted a great deal of attention among researchers because of their enhanced antibacterial activity against vancomycin‐resistant strains. However, the lack of a clear insight into the mechanisms of action of these dimers hampers rational optimization of their antibacterial potency. Here, we describe the synthesis and antibacterial activity of novel vancomycin dimers with a constrained molecular conformation achieved by two tethers between vancomycin units. Conformational restriction is a useful strategy for studying the relationship between the molecular topology and biological activity of compounds. In this study, two vancomycin units were linked at three distinct positions of the glycopeptide (vancosamine residue (V), C terminus (C), and N terminus (N)) to form two types of novel vancomycin cyclic dimers. Active NC‐VV‐linked dimers with a stable conformation as indicated by molecular mechanics calculations selectively suppressed the peptidoglycan polymerization reaction of vancomycin‐resistant Staphylococcus aureus in vitro. In addition, double‐disk diffusion tests indicated that the antibacterial activity of these dimers against vancomycin‐resistant enterococci might arise from the inhibition of enzymes responsible for peptidoglycan polymerization. These findings provide a new insight into the biological targets of vancomycin dimers and the conformational requirements for efficient antibacterial activity against vancomycin‐resistant strains. 相似文献