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101.
A novel diode-pumped, efficient, quasi-end-pumping scheme that uses two lens ducts to achieve homogeneous pumping in a gain medium was proposed and evaluated. With this technique, room-temperature laser action at a pulse repetition frequency up to 20 Hz was demonstrated in 5%Tm, 0.5%Ho:LuLiF(4), which we grew by the Czochralski method. At 10 Hz a long-pulse laser output energy in excess of 24 mJ and a slope efficiency with respect to the incident pump energy of 10.7% were obtained. 相似文献
102.
M. Mihara R. Matsumiya K. Matsuta K. Shimomura M. Fukuda J. Komurasaki D. Nishimura D. Ishikawa T. Nagasawa T. Izumikawa T. Minamisono 《Hyperfine Interactions》2007,178(1-3):69-72
In order to study the local electronic structure of nitrogen impurity in rutile TiO2, we have measured double-quantum NMR spectra of short lived β-emitter 12N(I = 1, T 1/2 = 11 ms) implanted into a rutile single crystal by means of the β-NMR technique. The resonance line obtained at room temperature is well accounted for by the second order shift due to the quadrupole interaction at the oxygen substitutional site. The spectrum at 25 K has shown the other lines than the central diamagnetic line shifted by 10?15 kHz to both sides, which has been already shown in the previous data obtained with a different crystal orientation and an external field. The present results supports the existence of a paramagnetic state formed by the substitutional nitrogen impurities. 相似文献
103.
傅元勇 周书华T. Koike S. Kinoshita Y. Ma Y. Miura K. Miwa Y. Miyagi K. Shirotori T. Suzuki H. Tamura K. Tsukada M. Ukai K. Futatsukawa K. Hosomi M. Kawai M. Mimori N. Terada N. Maruyama K. Aoki H Fujioka Y Kakiguchi T. Nagae D. Nakajima H Noumi T Takahashi T.N. Takahashi A. Toyota M. Dairaku T. Fukuda S. Minami W. Imoto S. Aiimura K. Tanida 《中国物理快报》2007,24(8):2216-2218
From the ^12 C(π^+,K^+)^12 AC reaction the γ -rays of 261.6±0.24 ke V(7/2^+ →5/2^+)and 1481.7±0.7 ke V(1/2^+ →5/2^+) of ^11 A B,and 2667.3±2.8 keV(1^- 2 → 2^- 1)of ^12 A C hypernuclei have been identified using a large germanium detector array Hyperball2 at K6 beam line of KEK. The observed energies of the transitions 1481.7keV and 261.6 keV are significantly different from the values predicted by the shell model using the △ and SN parameters determined from the ^7 △ Li data. 相似文献
104.
D. -J. Qian H. Nakahara K. Fukuda K. -Z. Yang 《Journal of Dispersion Science and Technology》2013,34(3):1031-139
Monolayers of europium complexes on water surface have been directly visualized in the gas-liquid expanded region at different temperatures using Brewster angle microscopy (BAM). The film texture with network patterns of the complex (C18)2 Eu(DBM)4 and hs evolution with time and temperature of the subphase were examined. The average linear cell dimension and the polygon areas have been analyzed as a function of time and the temperature. The mechanism of the domain growth is qualitatively discussed. 相似文献
105.
Chiral macrocyclic amine 2 was found to be useful as an NMR chiral shift reagent for the determination of the enantiomeric purity and absolute configurations of several kinds of carboxylic acid and amino acid derivatives. 相似文献
106.
Masakazu Nakanishi Tomoko Ogi Yoshio Fukuda 《Journal of Thermal Analysis and Calorimetry》2010,101(1):391-396
We modified a commercially available thermogravimetric analyzer to introduce helium alone or with steam, oxygen or both, atmosphere
of which was controllable to be similar to that in a fixed-bed or an entrained-flow type gasifier, for studying basic properties
of biomass gasification. We also connected it to a gas chromatograph-mass selective detector for identifying materials produced
during the thermogravimetric analyses. Thermogravimetric analyses of Japanese cedar wood and identifications of the produced
materials at around 365 °C were measured as demonstrations. 相似文献
107.
T. Katsumata H. Okada T. Kikuta T. Fukuda 《Applied Physics A: Materials Science & Processing》1987,42(2):103-109
The wavelength dependence and polarization characteristics of the infrared light scattered from an undoped GaAs crystal were investigated in the 90° angle infrared light scattering configuration. The scattering is Rayleigh scattering from scatterers which are always associated with the dislocations, and they are classified into three types,S, L
A
, andL
G
scatterers, according to their polarization characteristics. TheS, L
A
, andL
G
-scatterers are thought to be small As clusters, large As precipitates and large Ga precipitates, respectively. 相似文献
108.
Shigetaka Fukuda 《代数通讯》2013,41(10):3265-3268
109.
Sverine Queyroy Haruki Nakamura Ikuo Fukuda 《Journal of computational chemistry》2009,30(12):1799-1815
This article illustrates practical applications to molecular dynamics simulations of the recently developed numerical integrators [Phys Rev E 2006, 73, 026703] for ordinary differential equations. This method consists of extending any set of ordinary differential equations in order to define a time invariant function, and then use the techniques of divergence‐free solvable decomposition and symmetric composition to obtain volume‐preserving integrators in the extended phase space. Here, we have developed the technique by constructing multiple extended‐variable formalism in order to enhance the handling in actual simulation, and by constituting higher order integrators to obtain further accuracies. Using these integrators, we perform constant temperature molecular dynamics simulations of liquid water, liquid argon and peptide in liquid water droplet. The temperature control is obtained through an extended version of the Nosé‐Hoover equations. Analyzing the effects of the simulation conditions including time step length, initial values, boundary conditions, and equation parameters, we investigate local accuracy, global accuracy, computational cost, and sensitivity along with the sampling validity. According to the results of these simulations, we show that the volume‐preserving integrators developed by the current method are more effective than traditional integrators that lack the volume‐preserving property. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009 相似文献
110.
Akira Tanaka Mitsuhiro Fukuda Hiroyuki Nagai Masayuki Shinohara Shigeharu Onogi 《Journal of Polymer Science.Polymer Physics》1989,27(11):2283-2293
A new apparatus was designed to investigate the dynamic viscoelastic properties of solid polymer materials in the nonlinear viscoelastic region. The apparatus was combined with a birefringence apparatus in such a way that birefringence could be measured simultaneously with stress under oscillatory deformation. The nonlinear viscoelastic behavior of bulk-crystallized high-density polyethylene films was examined. Nonlinearity of mechanical properties became evident around 30°C, while optical properties became markedly nonlinear around 50°C. The nonlinearity of viscoelastic properties changes very little when the films are swollen with tetrachloroethane. It is proposed that disruption of lamellae to crystallites in the drawing process is one of the most important causes of the nonlinear behavior of high-density polyethylene films. 相似文献