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991.
992.
Lithium ion conductivity of Li2SO4-Y2(SO4)3, Li2SO4-La2(SO4)3 and Li2SO4-Li3PO4 systems has been measured as a function of composition and temperature using AC complex impedance methods. Substitution of the trivalent cations results in a small enhancement of the ionic conductivity within the limit of solid solution formation. Considerable increase of the conductivity results by substitution of PO43? for SO42?. The maximum conductivity observed is at 300°C for the composition Li2.2S0.8P0.2O4 with Ea = 0.8 eV. These results are discussed in terms of the structural properties. 相似文献
993.
In this study, pilot scale experiments were carried out to examine membrane fouling occurring in membrane bioreactors (MBR) with or without pre-treatment (coagulation/sedimentation). Especially, the influence of suspension viscosity and dissolved organic matter (DOM) on membrane fouling was investigated. The pre-coagulation/sedimentation process improved the performance of a MBR in terms of membrane permeability by controlling irreversible fouling and formation of thick cake layer. The upper limit of MLSS concentration for an efficient operation in MBR without pre-treatment was suggested to be around 10 g/L based on the measurement of suspension viscosity. In this study, it was difficult to directly relate membrane fouling to DOM detected in the membrane chamber. A series of laboratory scale dead-end filtration experiments was carried out to investigate which fractions in biomass suspension would be the most influential in the deterioration of membrane permeability. Based on the dead-end tests, it was shown that the deterioration of membrane permeability was mainly caused by the colloidal particle fraction in the biomass suspension. 相似文献
994.
A patient with Buerger's disease is described in whom reconstruction of a gangrenous forefoot with a free flap has been successfully performed. In order to limit the amputation level, a more aggressive approach toward reconstruction in young patients seems appropriate. To our knowledge, this is the first described case of free flap reconstruction of a gangrenous defect in a Buerger patient. 相似文献
995.
The purpose of this study was to compare University of Wisconsin (UW) solution with Euro-Collins (EC) solution in their cold preservation effects on rat limbs. Thirty-six Lewis rat limbs were preserved in EC solution (n=18) or UW solution (n=18) at 4 degrees C for 72 hr, and grafted orthotopically to a syngeneic rat using microsurgical techniques. The surgeon was blinded to the solution used. We evaluated the vascular patency rate and death rate of both groups at day 7 after surgery and performed histological evaluations of bone, muscle, growth plate, and articular cartilage for each specimen of successful grafts in both groups. The vascular patency rates of the EC and UW groups were 27.7% (5/18) and 11% (2/18), respectively, and showed no significant difference. The death rates of the EC and UW groups were 50% (9/18) and 60% (10/18), which were not significantly different. There were no clear differences in histological viability between both groups, in all tissues exclusive of bone marrow and muscle tissue. Our results showed that in comparing EC and UW solutions, one was not significantly superior to the other as a cold immersion storage medium after a 72 hr ischemia-induced reperfusion injury. 相似文献
996.
A Suyama R Iwakiri N Kimura A Nishi K Nakamura K Furukawa 《Canadian Metallurgical Quarterly》1996,178(14):4039-4046
We constructed hybrid Pseudomonas strains in which the bphA1 gene (coding for a large subunit of biphenyl dioxygenase) is replaced with the todC1 gene (coding for a large subunit of toluene dioxygenase of Pseudomonas putida Fl) within chromosomal biphenyl-catabolic bph gene clusters. Such hybrid strains gained the novel capability to grow on a wide range of aromatic hydrocarbons, and, more interestingly, they degraded chloroethenes such as trichloroethylene and cis-1,2-dichloroethylene very efficiently. 相似文献
997.
Detailed assignments of 13C n.m.r. signals of ethylene-1-octene and ethylene-4-methyl-1-pentene copolymers, members of the linear low-density polyethylene (LLDPE) family, are presented. The equations relating signal intensities to the monomer sequences are given. Using these equations, the characterization of these copolymers by the triad monomer sequences is possible. From the analysis by the triad sequence, it is suggested that these 1-olefins have a tendency to be present isolated in the copolymer chain. 相似文献
998.
S Tanimukai T Kimura H Sakabe Y Ohmizono T Kato H Miyazaki H Yamagishi Y Sonoda 《Canadian Metallurgical Quarterly》1997,25(10):1025-1033
To determine the hematopoietic actions of recombinant human c-Mpl ligand (thrombopoietin [TPO]), we studied its effects on the proliferation and differentiation of highly purified CD34+ blood progenitors in plasma-containing and serum-free culture. TPO alone promoted the growth of small megakaryocyte colonies (CFU-Meg) in numbers two to three times greater than those produced by interleukin (IL)-3. The combination of TPO and stem cell factor (SCF) exerted a significant synergistic effect on CFU-Meg formation. In the presence of TPO and IL-3 or granulocyte/macrophage-colony stimulating factor (GM-CSF), a significant number of mixed colonies (CFU-Mix) were observed. The combination of TPO and Epo did not increase the number of CFU-Meg, but did support erythroid-burst (BFU-E) and CFU-Mix colony formation. Interestingly, the combination of TPO with cytokines known to have burst-promoting activity (BPA), including IL-3, GM-CSF, IL-9, and SCF, increased the number of BFU-E and CFU-Mix in the presence of Epo. The BPA of TPO was further investigated by delayed addition of Epo on day 6 after incubation with TPO from day 0. None of the BFU-E or CFU-Mix survived, indicating that TPO acted as a costimulant exclusively for Epo. Moreover, a neutralizing anti-human Mpl receptor polyclonal antibody completely abrogated the BPA of TPO, demonstrating that this effect was mediated through the Mpl receptor. Finally, experiments in single-cell clone sorting and serum-free culture clearly demonstrated that a combination of TPO and Epo directly supported BFU-E and CFU-Mix. These results suggest that TPO acts not only in megakaryocytopoiesis but also in the early stage of hematopoiesis. 相似文献
999.
1000.
Kawahara T. Saeki S. Jyouno Y. Miyamoto N. Kobayashi T. Kimura K. 《Solid-State Circuits, IEEE Journal of》1998,33(1):126-132
A fabricated bandgap generator using 0.25-μm Flash memory process generated a stable reference voltage under 4 V, boosted from an external power supply of 2.5 V. The generated voltage was 1.297±0.025 V at a power supply of 4 V±10%; the temperature dependence was +0.7 mV/°C. The characteristics of a triple-well bipolar transistor for the Flash memory process are sufficient for a reference voltage generator; fT is 230 MHz, and HFE is 70. Dynamic operation reduced the average current consumption from 306 to 8.6 μA. Fabricated voltage-doubler circuits generated a voltage 1.8 times larger than that from conventional charge-pump circuits 相似文献