摘要：A method to design a birefringent plate （BP） for broadening spectrum in a regenerative amplifier is presented. Using this method, we design a quartz BP with thickness of 761μm inserted into a Ti：sapphire regenerative amplifier. The gain narrowing effect is reduced efficiently, and the experimental results agree with the calculation well. The bandwidth is broadened from 28 to 62 nm using the designed quartz BP and the pulses are compressed to ～23 fs.

摘要：Interferometric optical testing using computer-generated hologram （CGH） has provided an approach to highly accurate measurement of aspheric surfaces. While designing the CGH null correctors, we should make them with as small aperture and low spatial frequency as possible, and with no zero slope of phase except at center, for the sake of insuring low risk of substrate figure error and feasibility of fabrication. On the basis of classic optics, a set of equations for calculating the phase function of CGH are obtained. These equations lead us to find the dependence of the aperture and spatial frequency on the axial distance from the tested aspheric surface for the CGH. We also simulate the optical path difference error of the CGH relative to the accuracy of controlling laser spot during fabrication. Meanwhile, we discuss the constraints used to avoid zero slope of phase except at center and give a design result of the CGH for the tested aspheric surface. The results ensure the feasibility of designing a useful CGH to test aspheric surface fundamentally.

摘要：As the base of modern electronic industry,field-effect transistor(FET) requires the channel material to have both moderate bandgap and high mobility. The recent progresses indicate that few-layer black phosphorus has suitable bandgap and higher mobility than two-dimensional(2D) MoS_2, but the experimentally achieved maximal mobility(1000 cm^2 V^(-1) s^(-1)) is still obviously lower than those of classical semiconductors(1,400 and 5,400 cm^2 V^(-1) s^(-1) for Si and InP). Here, for the first time, we report on monolayer antimonide phosphorus(SbP) as a promising 2D channel material with suitable direct bandgap, which can satisfy the on/off ratio, and with mobility as high as 10~4 cm^2 V^(-1) s^(-1)based on density functional theory calculation. In particular,α-Sb_(1-x)P_x monolayers possess 0.3–1.6 eV bandgaps when0.1 ≤ x ≤ 1, which are greater than the minimum bandgap(0.4 eV) required for large on/off ratio of FET. Surprisingly,the carrier mobilities of α-Sb_(1-x)P_x monolayers exhibit very high upper limit approaching 2×10~4 cm^2 V^(-1) s^(-1) when 0 ≤x ≤ 0.25 due to the ultra-small effective mass of holes and electrons. This work reveals that 2D SbP with both suitable bandgap and high mobility could be a promising candidate as eco-friendly high-performance FET channel materials avoiding short-channel effect in the post-silicon era, especially when considering the recent experimental success in realizing arsenide phosphorus(AsP) with similar structure.

摘要：Based on the proper assumptions and approximations, the coupling mechanism of the electromagnetic acoustic transducer (EMAT) for ultrasonic generation within ferromagnetic material was studied by analyzing the eddy current distribution, Lorentz force, magnetostriction force and magnetization force. Some useful numerical calculations are presented to explain the EMAT behavior with general geometric arrangements. It is indicated that for the ferromagnetic material the magnetostriction effect dominates the EMAT phenomenon for ultrasonic wave generation in low magnetic field intensity, while the material does not reach its magnetizing saturation. But, with the increase of the bias magnetic field and saturation, the magnetostrictive terms will make no contributions to the ultrasonic generation and the Lorentz force becomes the only exciting mechanism. It is important to determine both the Lorentz and magnetostriction forces and select the appropriate working manner for achieving an optimized design.

摘要：This review is intended to help clinicians design drug regimens for special populations of critically ill patients with extremes of body size, habitus and composition that make drug choice or dosing particularly challenging due to the lack of high-level evidence on which to make wellinformed clinical decisions. The data sources included a literature search of MEDLINE and EMBASE with reviews of reference lists of retrieved articles. Abstracts of original research investigations and review papers were reviewed for their relevance to drug choice or dosing in the following special critically ill populations: patients with more severeforms of bodyweight or height, patients with amputations or missing limbs, pregnant patients, and patients undergoing extracorporeal membrane oxygenation or plasma exchange. Relevant papers were retrieved and evaluated, and their associated reference lists were reviewed for citations that may have been missed through the electronic search strategy. Relevant original research investigations and review papers that could be used to formulate general principles for drug choice or dosing in special populations of critically ill patients were extracted. Randomized studies with clinically relevant endpoints were not available for performing quantitative analyses. Critically ill patients with changes in body size, habitus and composition require special consideration when designing medication regimens, but there is a paucity of literature on which to make drug-specific, high-level evidencebased recommendations. Based on the evidence that is available, general recommendations are provided for drug choice or dosing in special critically ill populations.