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ABSTRACTExtensive finite element analyses of cracked pipes with different crack sizes and orientations have been conducted to investigate effects of creep properties of materials on the unified creep constraint parameter Ac. The results show that the constraint parameter Acis independent on Norton’s coefficient A, and it is only affected by the creep exponent nof materials. For a given crack size, with increasing n, Acdecreases and constraint level increases. The Acof lower constraint cracks is more sensitive to n. The unified correlation equations between Acand nhave been obtained for cracked pipes with a wide range of crack sizes and constraint levels. They may be used to estimate the constraint parameter Acat different positions along the crack fronts in cracked pipes made of materials with different nvalues. The two-parameter C*-Acapproach for assessing creep life of cracked pipes has also been discussed.

Due to their great stability and special cavities, metal‐organic cages (MOCs) are increasingly considered as promising nanocarriers for drug delivery. However, the size and surface dilemmas restrict their further biomedical applications. The ultrasmall size of MOCs facilitates tumor penetration but suffers from quick clearance and poor accumulation at the tumor site. Hydrophobicity of MOC surfaces improves internalization into tumor cells while causing low blood circulation time as well as poor biocompatibility. Therefore, it remains challenging for the MOC‐based drug delivery nanoplatform to realize high therapeutic efficacy because it requires different or even opposite dimensions and surface characteristics in different steps of circulation, penetration, accumulation, and internalization processes. In this study, an unprecedented phototriggered self‐adaptive platform (ZnPc@polySCage) is developed by integrating functionalized MOCs and a photodynamic therapy based reactive oxygen species responsive strategy to realize high‐efficiency tumor‐specific therapy. ZnPc@polySCage remains hydrophilic and stealthy during circulation, and retains its small original size for tumor penetration, while transforming to a larger size for effective accumulation and hydrophobic for enhanced internalization under laser irradiation in tumor tissue. With these essential transitions, ZnPc@polySCage demonstrates prominent antitumor effects. Overall, the work provides an advantageous strategy for functional MOC‐based platforms and biomedical applications. An unprecedented phototriggered self‐adaptive platform (ZnPc@polySCage) is established by integrating functionalized metal‐organic cages and a photodynamic therapy based reactive oxygen species responsive strategy to realize tumor‐specific drug delivery. The tailored ZnPc@polySCage stays hydrophilic and stealthy during circulation. When reaching the tumor site, the small size ensures deep penetration, and the phototriggered transformation to larger size and hydrophobicity enhances the retention and internalization in the tumor site.

The attitude maneuver parameter is derived from six elements of satellite orbit in ECI for traditional yaw-steering method. Only the Doppler centroid frequency of satellite main axis is compensated to zero. The error slant range and Doppler centroid frequency drift arose by the installation error between antenna and satellite and the beam angle departing from coordinate axis in elevation and azimuth direction are not removed. The requirements of SAR system time order and on-board real-time processor of response SAR satellite isn't satisfied. A new strategy of SAR antenna beam to target in zeros-Doppler plane of ECF was proposed so that Doppler frequency of beam center for fast response SAR satellite would be zero. Firstly, the accurate time order and look parameter was computed. Secondly, satellite's three axes direction was derived from SAR beam's three axes direction in ECF. Finally, the attitude maneuver parameters were obtained. The simulation results by Matlab show that applying the strategy to the fast response SAR satellite, the Doppler frequency 29kHz of earth rotation, 360Hz of installation error and 3950Hz of the beam departing angle are compensated to 0 Hz. Simultaneously the slant error 6.28 km is compensated to meter level. [ABSTRACT FROM AUTHOR]