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991.
Chang‐Hyuk Choi Hong‐Tae Kim Jung‐Yoon Choe Seong‐Kyu Kim Gi‐Whan Choi SangHoon Jheon Jong‐Ki Kim 《Journal of synchrotron radiation》2010,17(3):393-399
In vivo microstructures of the affected feet of collagen‐induced arthritic (CIA) mice were examined using a high‐resolution synchrotron radiation (SR) X‐ray refraction technique with a polychromatic beam issued from a bending magnet. The CIA models were obtained from six‐week‐old DBA/1J mice that were immunized with bovine type II collagen and grouped as grades 0–3 according to a clinical scoring for the severity of arthritis. An X‐ray shadow of a specimen was converted into a visual image on the surface of a CdWO4 scintillator that was magnified using a microscopic objective lens before being captured with a digital charge‐coupled‐device camera. Various changes in the joint microstructure, including cartilage destruction, periosteal born formation, articular bone thinning and erosion, marrow invasion by pannus progression, and widening joint space, were clearly identified at each level of arthritis severity with an equivalent pixel size of 2.7 µm. These high‐resolution features of destruction in the CIA models have not previously been available from any other conventional imaging modalities except histological light microscopy. However, thickening of the synovial membrane was not resolved in composite images by the SR refraction imaging method. In conclusion, in vivo SR X‐ray microscopic imaging may have potential as a diagnostic tool in small animals that does not require a histochemical preparation stage in examining microstructural changes in joints affected with arthritis. The findings from the SR images are comparable with standard histopathology findings. 相似文献
992.
Chitosan-montmorillonite nanocomposites were prepared by an ion exchange reaction between water soluble oligomeric chitosan and a Na+-montmorillonite. The chitosan-montmorillonite nanocomposites were rapidly prepared within 1 h due to the high affinity between the chitosan and the montmorillonite clay host. The basal spacings of the composites were in a range of 14.5-19.6 Å depending on the mixing ratio of chitosan to clay. According to the thermogravimetric analysis (TG) and powder X-ray diffraction analysis the thermal stability of chitosan was remarkably improved in the interlayer space due to the strong electrostatic interaction of cationic chitosan molecules with anionic silicate layers. From the antimicrobial activity test it was found that the nanocomposites showed a synergistic effect in the antimicrobial activity against to Escherichia coli and Staphylococcus aureus. 相似文献
993.
A high quality factor (Q-factor) is one of the major requirements of high-performance resonators. An understanding of the dissipation mechanism is crucial for maximizing the quality factor by reducing the energy loss. Thermoelastic damping has been well-known as the important intrinsic dissipation that affects the quality factor of micro-resonators. In this study, a finite element formulation based on the weak form of fully coupled thermoelastic problems is suggested. The coupled thermoelastic equation usually leads to a large-size complex eigenvalue problem, which is very massive and time-consuming to solve. Therefore, we also applied the model order reduction (MOR) scheme to this coupled multiphysical problem in order to achieve computational efficiency. The present approach is validated by comparing the numerical results and analytical solutions. 相似文献
994.
Nishimura K Browder TE Adachi I Aihara H Arinstein K Aushev T Bakich AM Balagura V Barberio E Belous K Bhardwaj V Bischofberger M Bondar A Bozek A Bračko M Chang MC Chao Y Chen A Chen KF Chen P Cheon BG Chiang CC Cho IS Choi Y Dalseno J Danilov M Doležal Z Drutskoy A Eidelman S Gabyshev N Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hyun HJ Iijima T Inami K Itoh R Iwabuchi M Iwasaki Y Joshi NJ Julius T Kang JH Kapusta P Kawai H Kawasaki T Kichimi H Kiesling C Kim HJ 《Physical review letters》2010,105(19):191803
We report a first measurement of inclusive B→Xsη decays, where Xs is a charmless state with unit strangeness. The measurement is based on a pseudoinclusive reconstruction technique and uses a sample of 657×10(6)BB pairs accumulated with the Belle detector at the KEKB e+e- collider. For MXs < 2.6 GeV/c2, we measure a branching fraction of [26.1±3.0(stat)-2.1+1.9(syst)-7.1+4.0(model)]×10(-5) and a direct CP asymmetry of ACP=-0.13±0.04-0.03+0.02. Over half of the signal occurs in the range MXs > 1.8 GeV/c2. 相似文献
995.
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
996.
A method of tuning a one-dimensional guided-mode resonance grating through the use of an air-pressure-responsive membrane is demonstrated here using finite-element method simulation. The device consists of a titanium dioxide (TiO(2)) grating structure embedded in a flexible polydimethylsiloxane membrane. This grating has a resonant response to TM-polarized light at a wavelength dependent upon the refractive index of the surrounding medium. By varying the pressure by 5500 Pa, lateral strain may be applied to the grating; this allows resonances to be produced for medium refractive indices ranging from 1.33 to 1.50 for a fixed-wavelength 850 nm light source. 相似文献
997.
Yong Hwan Lim Bum Ho Choi Young Baek Kim Dong Chan Shin 《Applied Surface Science》2010,256(23):6997-7000
We investigated the effects of in situ plasma-treatment on optical and electrical properties of index-matched indium tin oxide (IMITO) thin film. To render the IMITO-coated surface hydrophilic and study the optical and electrical characteristics, we performed in situ oxygen plasma post-treatment without breaking vacuum. The 94.6% transmittance in the visible wavelength range (400-700 nm) increased on average to 96.4% and the maximum transmittance reached 98% over a broad wavelength range. The surface roughness and sheet resistance improved from 0.9 nm and 200 Ω/sq to 0.0905 nm and 100 Ω/sq, respectively, by in situ plasma post-treatment. We confirmed by contact angle measurement that the hydrophobic IMITO surface was altered to hydrophilic. The improved optical and electrical characteristics of in situ plasma-treated IMITO makes it adequate for high-resolution liquid crystal on silicon displays. 相似文献
998.
In this paper, we study an elliptic equation arising from the self-dual Maxwell gauged sigma model coupled with gravity. When the parameter τ equals 1 and there is only one singular source, we consider radially symmetric solutions. There appear three important constants: a positive parameter a representing a scaled gravitational constant, a nonnegative integer representing the total string number, and a nonnegative integer representing the total anti-string number. The values of the products play a crucial role in classifying radial solutions. By using the decay rates of solutions at infinity, we provide a complete classification of solutions for all possible values of and . This improves previously known results. 相似文献
999.
1000.
We consider the λ model, a generalization of the Potts model, with spin values {1, 2, 3} on the order-two Cayley tree. We describe the model ground states and prove that translation-invariant Gibb measures exist, which means that a phase transition exists. We establish that two-periodic Gibbs measures exist. 相似文献