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H.S. Shin M.J. Dedicatoria 《Physica C: Superconductivity and its Applications》2010,470(20):1329-1333
In the case of 2G coated conductor (CC) tapes, it has been reported that thin–thick CC tapes with IBAD substrate showed a superior electromechanical property even at smaller bending radius compared with the cases of 1G BSCCO tapes. Considering the application of CC tapes it is significant to evaluate the transport property under operating environment, because CC tapes might experience a change in operating pressure that can affect its current carrying capacity due to temperature variation and deformation. This study was focused on the Ic degradation behavior in bent CC tapes under pressurized liquid nitrogen. Differently processed YBCO and SmBCO CC tapes with IBAD substrate are used as samples. The bending strain characteristics at elevated pressure levels were evaluated by using the ρ-shaped sample holder which can induce different bending strain values at pressured state. Depressurization and thermal cycling were performed to check the reversibility of Ic in CC tapes. Vacuuming tests were also carried out to investigate the characteristics of Ic at different LN2 temperature levels. 相似文献
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In the experiment, the effect of pressurization on the survival as well as acidifying and proteolytic activity of mesophilic commercial starters used for cheesemaking was studied. The samples were exposed to a single and a double (after 24 h) pressurization in the range of 200-800 MPa, for 15 minutes, at 20 °C. Analyses were performed immediately after the processing as well as after 1, 2, and 3 weeks of storage at 4 °C. A double processing at 600 and 800 MPa caused an irreversible reduction in the number of microorganisms, inhibited the process of milk acidification but preserved approximately 20% of the initial proteolytic activity of the bacterial enzymes. 相似文献
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Eduard Rogatsky Kara BraatenGreg Cruikshank Harsha JayatillakeBingNa Zheng Daniel T. Stein 《Journal of chromatography. A》2009,1216(45):7721-7727
Solvent flow, generated by HPLC pumps is consistent and accurate. This statement, while true for single column (one dimensional) liquid chromatography applications, may not apply to column switching applications. Connection of pumps and/or columns to one flow path may cause substantial pressure changes. Immediate post valve switch pressure differences between pumps can cause backflow where the mobile phase stored at higher pressure will temporary flow into the lower pressure area. A more common side effect of column switching is flow inconsistency during pump pressurization. For the duration of pump pressurization, liquid flow through the column will be smaller than expected since the HPLC column acts like a flow restrictor. 相似文献
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The concentration and size distribution of bulk nanobubbles (ultrafine bubbles) of air in liquid was measured before and after increasing the static pressure. It was found that, after pressurization, the number concentration decreased and the size increased. The effect of pressurization is to compress the bubbles and decrease the distance between solids on the bubble surface, which act as nucleation sites for bubble growth and coalescence when the static pressure is returned to atmospheric pressure. 相似文献
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以环形线负载驱动模型为基础,分析了环形线负载驱动变曲率反射镜难以兼顾大中心形变与高精度面形保持的原因;从薄板弹性理论出发,得到了一种气动驱动变厚变曲率反射镜物理模型.理论分析表明,将反射镜的厚度分布从等厚改为变厚,并采用气压均匀驱动替代推力环环形驱动,反射镜不仅能产生大的中心形变,而且在形变过程中的面形精度也远高于环形线负载驱动变曲率反射镜的.基于超硬铝反射镜样片的试验验证了对变厚变曲率反射镜的理论分析;试验中,反射镜初始面形精度接近λ/50(632.8nm),施加0.032 MPa驱动气压产生约22μm中心形变时,反射镜面形精度依然优于λ/20(632.8nm),证明该气动驱动结合变厚设计这一技术具有较大的应用潜力. 相似文献
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Zoltn Nmet Bla Hegeds Csaba Szntay Jr. Janisz Sztatisz Gyrgy Pokol 《Thermochimica Acta》2005,430(1-2):35-41
The effects of high static pressure on the polymorphic modifications A and B of famotidine were examined by differential scanning calorimetry, infrared and Raman spectroscopy, and X-ray powder diffractometry. The obtained effects appeared to differ significantly depending on whether they were monitored by DSC or any of the other above techniques. In particular, DSC measurements tend to deceptively amplify a tendency of the pure modification B to turn into the more stable form A under pressurization, while the spectroscopic methods and XRPD exhibit no essential change in the crystal structure of the metastable form B. The apparent morphological transformation in the pressed samples stems from the nature of the DSC method itself. 相似文献
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A porous core electroosmosis pump was studied and improved in accordance with the electroosmosis theory. Hexamethylene tetraamine (HMTA) was used as the additive of pump carrier solution to improve the flow rate stability and delivery efficiency. The influences of the electric field strength, porous core dimension and acetonitrile concentration of carrier solution on the pump flow rate and output pressure were investigated in detail. The improved electroosmosis pump can provide not only steady flow rate and large flow range, but also moderate output pressure. With the pump carrier solution of 0.5 mmol/L HMTA and the working voltage of 4950 V, the pump output pressure, flow rate and delivery efficiency achieved 1.1 MPa, 1.3 mL/min and 3.2 mL/(min mA), respectively. The pump can be employed for mobile phase delivery in the reversed-phase chromatographic separation of monolithic silica columns. 相似文献
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