Analysis of thermal stability and pyrolysis kinetic of dibutyl phosphate-based ionic liquid through thermogravimetry,gas chromatography/mass spectrometry,and Fourier transform infrared spectrometry

Journal of Thermal Analysis and Calorimetry - The impingement of CuO-water nanofluid flows upon a cylinder subject to a uniform magnetic field with constant surface temperature and embedded in...     

盐酸阿米替林/海藻酸钠/壳聚糖微球的制备及释放性能

盐酸阿米替林;海藻酸钠;壳聚糖;微球;交联;乙二醇二缩水甘油醚     

Quantitative gradient estimates for harmonic maps into singular spaces

In this paper, we show the Yau’s gradient estimate for harmonic maps into a metric space (X, d_X) with curvature bounded above by a constant κ (κ ? 0) in the sense of Alexandrov. As a direct application, it gives some Liouville theorems for such harmonic maps. This extends the works of Cheng (1980) and Choi (1982) to harmonic maps into singular spaces.

     

Terahertz emission in tenuous gases irradiated by ultrashort laser pulses

Mechanism of terahertz (THz) pulse generation in gases irradiated by ultrashort laser pulses is investigated theoretically. Quasi-static transverse currents produced by laser field ionization of gases and the longitudinal modulation in formed plasmas are responsible for the THz emission at the electron plasma frequency, as demonstrated by particle-in-cell simulations including field ionization. The THz field amplitude scaling with the laser amplitude within a large range is also discussed.     

Ring opening metathesis polymerization of bisnorbornene derivatives linked by Cp2Ni2(μ-S)2 bridge

ROMP of 2 with Grubbs I catalyst in CH₂Cl₂ furnished the corresponding polymer 5 which was characterized by spectroscopic means, particularly, MAS ¹³NMR. The EXAFS of 5 results were compared with those of the monomeric starting material 2 and the X-ray data of 2.     

Sharp spectral gap and Li–Yau’s estimate on Alexandrov spaces

In the previous work (Zhang and Zhu in J Differ Geom, http://arxiv.org/pdf/1012.4233v3, 2012), the second and third authors established a Bochner type formula on Alexandrov spaces. The purpose of this paper is to give some applications of the Bochner type formula. Firstly, we extend the sharp lower bound estimates of spectral gap, due to Chen and Wang (Sci Sin (A) 37:1–14, 1994), Chen and Wang (Sci Sin (A) 40:384–394, 1997) and Bakry–Qian (Adv Math 155:98–153, 2000), from smooth Riemannian manifolds to Alexandrov spaces. As an application, we get an Obata type theorem for Alexandrov spaces. Secondly, we obtain (sharp) Li–Yau’s estimate for positve solutions of heat equations on Alexandrov spaces.     

Enantioselective Aldol Type Reactions of Acetate Titanium Enolate with α,β-Unsaturated Aldehyde-TiCl4 Complex

The camphor-derived N-acetyloxazolidinethione has been used to effect enantioselective aldol type reaction of the derived thioimide titanium enolate with unsaturated aldehyde-TiCl₄ complex. The observed facial selectivity is best explained by an open transition state model.     

有质动力和静电分离场对激光等离子体流体力学状态的影响

利用建立在欧拉坐标系上的一维电子_离子双流双温流体力学程序, 模拟了超短脉冲强激光 (1×1015W/cm2, 150fs)与线性密度梯度等离子体相互作用的流体力学过程. 模拟结果显示，入射激光与临界密度面的反射光叠加，在临界密度以下区域形成局域驻波， 产生的强有质动力在低密区驱动电子形成周期性密度结构——Bragg光栅，激光的反射被增 强. 临界密度处有质动力将等离子体分成向内和向外运动的两部分. 由于离子所受的有质动 力和热压强的梯度力远小于电子，体系产生了强静电分离场，离子的运动主要由该静电分离 场决定. 对双流双温模型和单流双温模型的模拟结果进行了比较. 当有质动力和热压强梯度 力较大时，两种模型对等离子体流体力学状态的描述有明显差异，单流双温模型无法描述此 时的流体力学状态. 关键词： 有质动力 密度调制 双流双温流体力学模型 单流模型     

超短电子脉冲在聚焦强激光场中的三维有质动力散射

采用三维测试粒子模拟(test-padicle simulation)的方法，研究了聚焦的飞秒脉冲强激光与超短电子束进行有质动力的散射过程.详细讨论了超短电子束经过不同激光延迟下有质动力散射的空间分布特征和能谱特征.提出了通过测量电子束的空间分布和能谱分布实现对超短脉冲电子束的脉冲宽度测量的方法. 关键词： 有质动力散射 聚焦的飞激光 飞秒电子束