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991.
992.
Yu He Zhiwei Hu Mengda Ren Changkun Ding Peng Chen Qun Gu Qiong Wu 《Journal of materials science. Materials in medicine》2014,25(2):561-571
Two types of fibers were prepared by using bio-based materials: a mono-filament made from poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and a multi-filament made from poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polylactic acid (PLA) blend. The two fibers were evaluated for mechanical properties, biocompatibility and degradability for the potential application as medical sutures. The PHBHHx fiber showed remarkable biocompatibility by H.E. Stainning, with very little impact to the surrounding tissues. The degradation of the fiber was observed by SEM after implantation for 36 weeks, and the major degradation product was detected after 96 weeks. Consistently, the PHBHHx fiber maintained more than half of the mechanical properties after 96 weeks. The other fiber was prepared by twisting PHBV/PLA blend strands to a bunch, and showed high biocompatibility and relatively high degradability. The bunched structure loosed after 36 weeks of implantation. These low-cost and easily prepared fibers have great potential in medical applications, since they could avoid the formation of fibrous capsule, reduce the size of scar, and degrade into non-toxic and even beneficial products. 相似文献
993.
An adaptive Kalman filtering based State of Charge combined estimator for electric vehicle battery pack 总被引:3,自引:0,他引:3
Ah counting is not a satisfactory method for the estimation of the State of Charge (SOC) of a battery, as the initial SOC and coulombic efficiency are difficult to measure. To address this issue, a new SOC estimation method, denoted as “AEKFAh”, is proposed. This method uses the adaptive Kalman filtering method which can avoid filtering divergence resulting from uncertainty to correct for the initial value used in the Ah counting method. A Ni/MH battery test procedure, consisting of 8.08 continuous Federal Urban Driving Schedule (FUDS) cycles, is carried out to verify the method. The SOC estimation error is 2.4% when compared with the real SOC obtained from a discharge test. This compares favorably with an estimation error of 11.4% when using Ah counting. 相似文献
994.
Three-Dimensional Numerical Study of Fluid and Heat Transfer Characteristics of Dimpled Fin Surfaces
In the present study, a code based on the nonorthogonal curvilinear coordinates is developed with a collocated grid system generated by the two-boundary method. After validation of the code, it is used to compare simulated results for a fin-and-tube surface with coupled and decoupled solution methods. The results of the coupled method are more agreeable with the test data. Simulation for dimpled and reference plain plate fin-and-tube surfaces are then conducted by the coupled method within a range of inlet velocity from 1.0 m/s to 5 m/s. Results show that at identical pumping power the dimpled fin can enhance heat transfer by 13.8–30.3%. The results show that relative to the reference plain plate fin-and-tube surface, heat transfer rates and pressure drops of the dimpled fin increase by 13.8%–30.3% and 31.6%–56.5% for identical flow rate constraint. For identical pumping power constraint and identical pressure drop constraint, the heat transfer rates increase by 11.0%–25.3% and 9.2%–22.0%, respectively. By analyzing the predicted flow and temperature fields it is found that the dimples in the fin surface can improve the synergy between velocity and fluid temperature gradient. 相似文献
995.
新能源汽车电动涡旋压缩机具有效率高、可靠性好、无极调速等特点,是新能源汽车产业的关键零部件.对压缩机运行时,泵体轴向间隙的径向泄漏进行了分析,并根据泵体不同压缩腔之间存在压差的特点,提出了密封方案,在压缩机上应用并验证了整机性能与摩擦磨损改善效果. 相似文献
996.
采用两种不同的样品处理方法在同样的色谱条件下检测三聚氰胺含量,研究比较两种方法会对检测结果带来的影响。快速处理方法的加标回收率为84.9%~87.6%,固相萃取处理方法加标回收率为96.8%~102.0%,快速处理方法是应对突发事件测定的首选,固相萃取处理方法是定量准确测定的首选。 相似文献
997.
Crack-free Sm-doped Bi2Ti2O7 (Sm:BTO) thin films with strong (111) orientation have been prepared on Pt (111) substrates using a chemical solution deposition (CSD) method. The structural properties and crystallizations were studied by X-ray diffraction. The surface morphology and quality were examined using atomic force microscopy (AFM). The insulating and dielectric properties were also evaluated at room temperature. The results demonstrate that the Sm:BTO films exhibit improved electrical performances as compared to the pure Bi2Ti2O7 thin films and suggest a strong potential for utilization in microelectronics devices. 相似文献
998.
999.
Radiation-shielding concrete was made with ironstone aggregate. The compressive strength is affected by multi factors. The
electrical conductive properties and smart performance was discovered and investigated. Experimental results show that concrete
conductivity rapidly declines with increasing loading, and the conductivity is much lower than the initial value of conductive
aggregate of concrete, which may be related to special characters of ironstone. This kind of concrete has widely potential
applications due to its special characters and low cost.
Funded by the National Natural Science Foundation of China(No. 40674060) 相似文献
1000.