摘要：Uniting dual-modality of fluorescence and photoacoustic(PA)imaging into theranostic nanoprobes is imperative for spatiotemporally tracking of drug delivery,distribution,and ***,we present a rational design strategy of molecularly precise amphiphilic prodrugs BP_(n)-Cy-S-CPT(n=0,5,and 20,refers to the degree of polyethylene glycol(PEG)polymerization;CPT=camptothecin)to tune their self-assembly behaviour,innovatively integrating dual-modal PA and near-infrared(NIR)fluorescence imaging in a single-molecular *** these elaborately designed prodrugs,it is found that only BP_(20)-Cy-S-CPT could form uniform and highly stable self-assemblies,especially in showing synergistically enhanced PA and dualchannel NIR *** detail,PA signal is employed to trace the in vivo delivery with high spatial resolution,meanwhile the glutathione(GSH)-triggered dual-channel fluorescence response could real-timely monitor drug distribution and release without"blind spot".The results of in vivo dual-modal PA/NIR imaging have verified that BP_(20)-Cy-S-CPT displayed synergistic targeting(including passive,active,and activatable targeting)for tumor-specific delivery,and thereby executed CPT release in the tumor ***,our molecularly precise BP_(20)-Cy-S-CPT self-assemblies could make a breakthrough to spatiotemporally track the in vivo drug release profile,expanding the intelligent theranostic toolbox for precise cancer treatment.

摘要：The application of the adaptive growth method is limited because several key techniques during the design process need manual intervention of designers. Key techniques of the method including the ground structure construction and seed selection are studied, so as to make it possible to improve the effectiveness and applicability of the adaptive growth method in stiffener layout design optimization of plates and shells. Three schemes of ground structures, which are comprised by different shell elements and beam elements, are proposed. It is found that the main stiffener layouts resulted from different ground structures are almost the same, but the ground structure comprised by 8-nodes shell elements and both 3-nodes and 2-nodes beam elements can result in clearest stiffener layout, and has good adaptability and low computational cost. An automatic seed selection approach is proposed, which is based on such selection rules that the seeds should be positioned on where the structural strain energy is great for the minimum compliance problem, and satisfy the dispersancy requirement. The adaptive growth method with the suggested key techniques is integrated into an ANSYS-based program, which provides a design tool for the stiffener layout design optimization of plates and shells. Typical design examples, including plate and shell structures to achieve minimum compliance and maximum bulking stability are illustrated. In addition, as a practical mechanical structural design example, the stiffener layout of an inlet structure for a large-scale electrostatic precipitator is also demonstrated. The design results show that the adaptive growth method integrated with the suggested key techniques can effectively and flexibly deal with stiffener layout design problem for plates and shells with complex geometrical shape and loading conditions to achieve various design objectives, thus it provides a new solution method for engineering structural topology design optimization.

摘要：Laminar flow design is one of the most effective ways to reduce the drag of a commercial aircraft by expanding the laminar flow region on the surface of the aircraft. As material science develops, the emergence of new materials such as low surface energy materials has offered new choices for laminar flow design of commercial aircraft. Different types of low surface energy micro-nano coatings are prepared to verify the effects on the boundary layer transition position and the drag of the airfoil through wind tunnel tests. The infrared thermal imaging technology is adopted for measuring the boundary layer transition, while the momentum integral approach is employed to measure the drag coefficient through a wake rake. Infrared thermal imaging results indicate that the coatings are capable of moving backward the boundary layer transition position at both a low velocity of Mach number 0.15 and a high velocity of Mach number 0.785. Results of the momentum integral approach demonstrate that the drag coefficients are reduced obviously within the cruising angle of attack range from 1° and 5° by introducing the low surface energy micro-nano coating technology.

摘要：To improve the accuracy of the vehicle crashworthiness simulation, it is necessary as well as important to integrate the valid forming effects of key parts. It has been agreed by many that one-step simulation results should be used only as a qualitative trend of the part but not as an engineering result for further structural analysis, especially for a relatively complex part. The study shows that it is inaccurate to analyze the forming effects with one-step simulation based on the geometry of the final part through comparison with the incremental simulation and verification with the actual part, whether in thickness or in plastic strain. However, incremental simulation is very time consuming and infeasible in the early stage of vehicle design due to lack- ing of forming tools and process parameters. An engineering approach is proposed to meet the requirement of accuracy as well as the time efficiency, where one-step simulation is conducted based on the geometry of the transformed part instead of the fi- nN part. The geometry of the transformed part is generated by simple die design engineering and proves to offer much more accuracy than the one-step simulation based on the final part geometry.

摘要：Based on digital signal processing theory,a novel method of designing optical notch filter is proposed for Mach-Zehnder interferometer with cascaded optical fiber rings coupled *** method is simple and effective,and it can be used to implement the designing of the optical notch filter which has arbitrary number of notch points in one free spectrum range(FSR).A design example of notch filter based on cascaded single-fiber-rings is *** this basis,an improved cascaded double-fiber-rings structure is presented to eliminate the effect of phase shift caused by the single-fiber-ring *** new structure can improve the stability and applicability of *** change of output intensity spectrum is finally investigated for each design parameter and the tuning characteristics of the notch filter are also discussed.

摘要：Inspired by the safe landing of a cat falling from a high altitude,a bio-inspired polygonal skeleton(BIPS) structure is proposed,and its nonlinear characteristics are systematically studied to explore its potential application in the suppression of vibration. The polygon is formed by the skeleton structure of the cat’s entire body and the ground. The BIPS system consists of two symmetrical bionic legs with three robs(as skeleton) and four horizontal springs(as muscle). Two bionic legs are connected through the bearing platform(as spine),which could adjust the distance between the two bionic legs. A theoretical model is developed to characterize its stiffness nonlinearity through geometrical and mechanical analysis. Parameter analysis reveals that the BIPS structure has diverse stiffness,including nonlinear positive stiffness and negative stiffness. By imitating adjustment of leg posture and telescopic function of the spine(control the distance between legs),these flexible stiffness properties can be adjusted by structure parameters. In addition,the load capacity and working range can also be designed by the length of the bars,the initial angle,the mounting position,and the spring stiffness. The experimental setup is established,and the vibration isolation performance under various excitation is tested. The experimental results verify the accuracy of the dynamic model and also show that the proposed BIPS structure can suppress the vibration effectively under a variety of excitations. These peculiarities may provide potential possibility of an innovative approach to passive vibration control and isolation.

摘要：Based on the theory of one-dimensional photonic crystal,an asymmetrical interleaver filter composed of thin-film glass cavities is *** thin-film glass cavities are cascaded in the *** cavity is formed by evaporating several layers of reflecting films on two surfaces of the glass *** with other proposed structures,this interleaver filter is very simple and easy to realize,and it has flat passband and stopband.A design example of a 50 GHz interleaver filter with the duty cycle of 1:5 is *** influence of the structural parameters of each reflecting film(including the glass cavity) on the spectral performance is *** the design results with duty cycles of 1:3 and 1:4 are also shown and analyzed.

摘要：This paper deals with a bi-extrapolated subgradient projection algorithm by intro- ducing two extrapolated factors in the iterative step to solve the multiple-sets split feasibility problem. The strategy is intend to improve the convergence. And its convergence is proved un- der some suitable conditions. Numerical results illustrate that the bi-extrapolated subgradient projection algorithm converges more quickly than the existing algorithms.

摘要：A high-sensitivity metal-coated long-period fiber grating(LPFG) sensor based on material dispersion is *** on the coupled mode theory,the influence of the material dispersion on the dual-peak characteristics of the metal-coated LPFG is *** considering the material dispersion,the jumping region of the dual-resonant-wavelength shifts toward the thinner film thickness,and the sensitivity of the dual-peak metal-coated LPFG sensor to liquid refractive index(RI) can be obtained to supply accurate parameter ***,two kinds of silver-coated LPFGs with different film thicknesses and grating periods are fabricated to monitor the salt solution,and the sensitivities of these two sensors are *** experimental results are consistent with the theoretical analyses.

摘要：A convenient and scalable synthesis of 1-amino-5-cyanonaphthalene was described.