超高效液相-质谱联用法同时测定诃子果实不同部位的6种成分含量

本研究建立了一种超高效液相-串联四极杆质谱多反应监测模式法同时定量6种诃子酚类有效成分:诃黎勒酸(chebulagic acid),五没食子酰葡萄糖(pentagalloyl glucose),木麻黄鞣宁(casua-rinin),鞣料云实素(corilagin),鞣花酸(ellagic acid)和没食子酸(gallic acid),选用半合成的酚类化合物4β-(L-乙酰半胱氨酸)-表儿茶素为内标。药材粉碎后用含内标的甲醇溶液超声提取,提取液用安捷伦ZORBAXEclipseX DB-C18(2.1×50mm,1.8建立方法对诃子μm)分析柱分离,甲醇-0.1%甲酸梯度洗脱,电喷雾电离源多反应模式监测。所6种成分的定量限均小于0.0868相关系数均大于μg·mL^(-1),在定量范围内成分与内标的峰面积比与成分质量浓度呈线性关系,0.99;方法回收率为83.4-108.1%;日内及日间精密度RSD分别为0.9-5.9和1.3-4.8。检测结果表明诃子果肉及种皮中这6种有效成分含量均高,以果肉中的含量最高,该法也可用于诃子及其复方的质量控制。

Laboratory radiative accretion shocks on GEKKO XⅡlaser facility for POLAR project

A new target design is presented to model high-energy radiative accretion shocks in polars. In this paper, we present the experimental results obtained on the GEKKO XII laser facility for the POLAR project. The experimental results are compared with 2 D FCI2 simulations to characterize the dynamics and the structure of plasma flow before and after the collision. The good agreement between simulations and experimental data confirms the formation of a reverse shock where cooling losses start modifying the post-shock region. With the multi-material structure of the target,a hydrodynamic collimation is exhibited and a radiative structure coupled with the reverse shock is highlighted in both experimental data and simulations. The flexibility of the laser energy produced on GEKKO XII allowed us to produce high-velocity flows and study new and interesting radiation hydrodynamic regimes between those obtained on the LULI2000 and Orion laser facilities.

Analytical modelling of the expansion of a solid obstacle interacting with a radiative shock

In this paper, we present a model characterizing the interaction of a radiative shock(RS) with a solid material, as described in a recent paper(Koenig et al., Phys. Plasmas, 24, 082707(2017)), the new model is then related to recent experiments performed on the GEKKO XII laser facility. The RS generated in a xenon gas cell propagates towards a solid obstacle that is ablated by radiation coming from the shock front and the radiative precursor, mimicking processes occurring in astrophysical phenomena. The model presented here calculates the dynamics of the obstacle expansion,which depends on several parameters, notably the geometry and the temperature of the shock. All parameters required for the model have been obtained from experiments. Good agreement between experimental data and the model is found when spherical geometry is taken into account. As a consequence, this model is a useful and easy tool to infer parameters from experimental data(such as the shock temperature), and also to design future experiments.

Experimental platform for the investigation of magnetized-reverse-shock dynamics in the context of POLAR

The influence of a strong external magnetic field on the collimation of a high Mach number plasma flow and its collision with a solid obstacle is investigated experimentally and numerically. The laser irradiation(I ～ 2 × 10^(14) W · cm^(-2)) of a multilayer target generates a shock wave that produces a rear side plasma expanding flow. Immersed in a homogeneous10 T external magnetic field, this plasma flow propagates in vacuum and impacts an obstacle located a few mm from the main target. A reverse shock is then formed with typical velocities of the order of 15–20 ± 5 km/s. The experimental results are compared with 2 D radiative magnetohydrodynamic simulations using the FLASH code. This platform allows investigating the dynamics of reverse shock, mimicking the processes occurring in a cataclysmic variable of polar type.

The Giant Radio Array for Neutrino Detection(GRAND):Science and design

The Giant Radio Array for Neutrino Detection(GRAND)is a planned large-scale observatory of ultra-high-energy(UHE)cosmic particles,with energies exceeding 10~8 Ge V.Its goal is to solve the long-standing mystery of the origin of UHE cosmic rays.To do this,GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched sensitivity.GRAND will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the atmosphere.Its design is modular:20 separate,independent sub-arrays,each of 10000 radio antennas deployed over 10000 km^2.A staged construction plan will validate key detection techniques while achieving important science goals early.Here we present the science goals,detection strategy,preliminary design,performance goals,and construction plans for GRAND.