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In this paper, the melting memory effect generated by a novel cyclic thermal treatment protocol with form II as "seeds" on the polymorphic transformation in isotactic polybutylene-1(iPB-1) was investigated. Polar Optical Microscope (POM), wide angle X-ray diffraction (WAXD) and Fourier transform infrared spectroscopy (FTIR) were used to study the changes of morphology and crystal form II → I transition during aging. Selected crystallization temperature (Tsc) and melting temperature (Tsm) were applied to generate residual nuclei of form II. Both cycled and uncycled samples were analyzed to demonstrate the formation of crystal I and polymorphic transformation. The results indicate that the melting memory has a significant effect on tetragonal modification, leading to an increased nucleation density and an accelerated nucleation speed. The ordered chain sequences in crystal II initiated the formation of crystal nuclei of form I, resulting in a rapid conversion and increased transition degree during the hexagonal crystal growth. Form I was found to have two formation pathways, including the transformation of the unstable crystal form II and the direct formation from residual crystal and melt, which have been rarely discussed before and may shed light on understanding of crystal formation mechanism in polymorphism polybutene-1. [ABSTRACT FROM AUTHOR]

In classical smoothed particle hydrodynamics (SPH) fluid simulation approaches, the smoothing length of Lagrangian particles is typically constant. One major disadvantage is the lack of adaptiveness, which may compromise accuracy in fluid regions such as splashes and surfaces. Attempts to address this problem used variable smoothing lengths. Yet the existing methods are computationally complex and non-efficient, because the smoothing length is typically calculated using iterative optimization. Here, we propose an efficient non-iterative SPH fluid simulation method with variable smoothing length (VSLSPH). VSLSPH correlates the smoothing length to the density change, and adaptively adjusts the smoothing length of particles with high accuracy and low computational cost, enabling large time steps. Our experimental results demonstrate the advantages of the VSLSPH approach in terms of its simulation accuracy and efficiency. [ABSTRACT FROM AUTHOR]

Solving algebraic equations over GF(2) is a problem which has a wide range of applications, including NP-Hard problems and problems related to cryptography. The existing mature algorithms are difficult to solve large-scale problems. Inspired by Schöning's algorithm and its quantum version, we apply related methods to solve algebraic equations over GF (2). The new algorithm we proposed has a significant improvement of solving efficiency in large-scale and sparse algebraic equations. As a hybrid algorithm, the new algorithm can not only run on a classic computer alone, but also use small-scale quantum devices to assist acceleration. And the new algorithm can be seen as an example of solving a large-scale problem on a small-scale quantum device. [ABSTRACT FROM AUTHOR]

We elaborate a high-power, high-efficiency cw Tm:YAP laser dual-end-pumped by the laser diode. With 41.9 W pumping power, we obtain a maximum cw output power of 14.7 W at 1988 nm with a slope efficiency of 43.8%, corresponding to an optical conversion efficiency of 35.1%. At the maximum laser output, we measure a beam quality of M ~ 1 .9. [ABSTRACT FROM AUTHOR]