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811.
Feasibility of carboxymethylcellulose with phenol moieties as a material for mammalian cell-enclosing subsieve-size capsules 总被引:1,自引:0,他引:1
Shinji Sakai Sho Ito Yuko Ogushi Ichiro Hashimoto Koei Kawakami 《Cellulose (London, England)》2008,15(5):723-729
Mammalian cell-enclosing capsules have been investigated as devices for bioproduction, cell therapy and stem cell research.
In this study, carboxymethylcellulose (CMC) with phenol moieties (CMC-Ph), synthesized through the conjugation reaction of
CMC and tyramine, was investigated as a material for these types of devices. Subsieve-size capsules of less than 100 μm in
diameter were prepared by extruding aqueous CMC-Ph solution into co-flowing liquid paraffin containing H2O2. The capsule diameter was controlled between 60–220 μm by changing the flow rate of liquid paraffin. There was no harmful
effect specific for CMC-Ph on mammalian cells enclosed in capsules. Feline kidney cells enclosed in subsieve-size CMC-Ph capsules
exhibited 87.0 ± 4.5% viability. In addition, the enclosed cells continued to grow over 13 days of study. These results demonstrated
the feasibility of CMC-Ph as a material for subsieve-size cell-enclosing capsules prepared via the droplet breakup technique
in a co-flowing water-immiscible fluid. 相似文献
812.
Yasufumi Watanabe Yuji Shibasaki Shinji Ando Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2004,42(1):144-150
We prepared new semiaromatic polyimides from alicyclic dianhydrides and aromatic diamines containing adamantyl and biadamantyl units. Polycondensations were performed in 1‐methyl‐2‐pyrrolidinone at room temperature for 7 h and then 80 °C for 23 h, giving poly(amic acid)s with inherent viscosities up to 0.58 dL/g. Poly(amic acid)s were converted to corresponding poly(imide)s by thermal treatment. Poly(imide)s showed relatively high thermal stability (5% weight loss around 450 °C) and low dielectric constants (2.69–2.79). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 144–150, 2004 相似文献
813.
The reflectance of a high-reflectance dielectric multilayer coating mirror tuned to a monochromatic laser wavelength was estimated from its transmittance which was measured with 0.4 ppm accuracy. The transmittance was calculated from its theoretical formula including three parameters (refractive indexes of low and high refractive films (nL, nH) and a number of layer units composed of a pair of one low and one high refractive film (N)) which were estimated from the incident beam angular dependence curve of the transmittance. This calculated transmittance agreed with that measured as a ratio of the laser beam power before and after the mirror with 6 ppm difference. 相似文献
814.
815.
Propagation of the cold lower hybrid waves in a cylindrical and a cylindrical tokamak plasmas is studied theoretically. The energy flow trajectory in spiral in the poloidal direction and extends along the toroidal direction, as well. The latter distance to the resonance layer is equal to √M/ma, in order (a: radius of plasma column). 相似文献
816.
Desorption kinetics of SiO in the reaction of O2 with Si(100) and (111) surfaces were investigated at surface temperatures between 1000 and 1300 K by using a pulsed molecular beam technique. The gaseous SiO product was detected by a mass spectrometer above 1000 K. At temperatures lower than 1050 K, the SiO signal appeared with an induction time after the O2 beam irradiation onto the surface, which means that the desorption occurs via sequential steps. The rate constants for two steps were obtained by a computer simulation of the relaxation waveforms of the SiO signal. The values obtained are in the same range as those of D'Evelyn et al. However, they are one order of magnitude larger than those of Yu and Eldridge. The activation energies for the two steps are 2.8 and 2.4 eV for both Si(100) and (111) surfaces. No significant difference between the two kinds of surfaces was found from these values. However, many etch pits were observed on the Si(100) surface after the reaction, while no such etch pits were formed on the Si(111) surface. The planes of the etch pits formed on the (100) surfaces consisted mostly of the {111} facets. 相似文献
817.
Mitsuaki Kodama Suzuyo Yoshio Shinji Yamaguchi Yoshiyasu Fukuyama Hisao Takayanagi Yasuhiro Morinaka Shuji Usui Yoshimasa Fukazawa 《Tetrahedron letters》1993,34(52):8453-8456
Both enantiomers of sarcophytols A (1) and T (2), cembranolide diterpenes isolated from a soft coral, were synthesized from a common chiral intermediate, obtained by baker's yeast reduction, using a stereospecific [2,3]Wittig rearrangement as the key step. 相似文献
818.
As in many primal—dual interior-point algorithms, a primal—dual infeasible-interior-point algorithm chooses a new point along the Newton direction towards a point on the central trajectory, but it does not confine the iterates within the feasible region. This paper proposes a step length rule with which the algorithm takes large distinct step lengths in the primal and dual spaces and enjoys the global convergence.Part of this research was done when M. Kojima and S. Mizuno visited at the IBM Almaden Research Center. Partial support from the Office of Naval Research under Contract N00014-91-C-0026 is acknowledged.Supported by Grant-in-Aids for Co-operative Research (03832017) of The Japan Ministry of Education, Science and Culture.Supported by Grant-in-Aids for Encouragement of Young Scientist (03740125) and Co-operative Research (03832017) of The Japan Ministry of Education, Science and Culture. 相似文献
819.
This paper describes the traveling tournament problem, a well-known benchmark problem in the field of tournament timetabling.
We propose a new lower bound for the traveling tournament problem, and construct a randomized approximation algorithm yielding
a feasible solution whose approximation ratio is less than 2+(9/4)/(n−1), where n is the number of teams. Additionally, we propose a deterministic approximation algorithm with the same approximation ratio
using a derandomization technique. For the traveling tournament problem, the proposed algorithms are the first approximation
algorithms with a constant approximation ratio, which is less than 2+3/4. 相似文献
820.
Tatsuo Nishitani 《偏微分方程通讯》2013,38(9):1289-1319
We study the Cauchy problem for second order hyperbolic equations with non negative characteristic form of two independent variables. We show that for such equations in divergence-free form, the Cauchy problem is well posed in the Gevrey class of order less than 5/2. 相似文献