氦透平膨胀机叶轮(理想气体)S_2流面流场计算

为保证核聚变装置EAST(Experimental Advanced Super-conducting Tokamak)氦低温系统的稳定运行,其核心部件氦透平膨胀机必须满足制冷量的要求;因此有必要用流线曲率法对低温氦透平膨胀机T2叶轮流场进行计算。经过计算得出T2叶轮子午面流场,同时也对叶轮性能进行分析,结果完全满足要求。     

具二次等式约束最小二乘问题的一种极端情形

本文研究具有二次等式约束的最小二乘问题(LSS): min‖Ax-b‖₂ s.t. ‖x‖₂=1, 其中A∈R^m×n, b∈R^m, 并假定‖A⁺b‖₂<1.重点关注一个极端情形: ‖A⁺b‖₂≈0. 敏度分析表明,这是一种病态问题. 基于Padé逼近给出了一种迭代解法. 数值算例表明,新方法在速度上较已有方法有优势.     

Monotone optimal control for a class of Markov decision processes

This paper provides a unified framework to study monotone optimal control for a class of Markov decision processes through D-multimodularity. We demonstrate that each system in this class can be classified as either a substitution-type or a complement-type system according to the possible transition set, which can be used as a classification mechanism that integrates a variety of models in the literature. We develop a generic proof of the structural properties of both types of system. In particular, we show that D-multimodularity is a generally sufficient condition for monotone optimal control of different types of system in this class. With this unified theory, there is no need to pursue each problem ad hoc and the structural properties of this class of MDPs follow with ease.     

Analyzing wavelength behavior of a cubic phase mask imaging system based on modulation transfer function

The wavefront coding technology is an effectively method for extending the depth of field. However, the phase delayed by the phase mask changes with light wavelength, and the chromatic aberration is caused by chromatic dispersion of the optical elements. The modulation transfer function (MTF) of the cubic phase mask (CPM) system is derived with considering the axial chromatic aberration and optical path difference variation with wavelength, and the wavelength behavior of CPM system is analyzed in details. We yield that the MTF is approximately wavelength invariant within a certain frequency bandwidth, and the bandwidth is nearly inverse proportional to wavelength and varies with axial chromatic aberration. The effect induced by dispersion of the CPM material is very weak. If the CPM system is illuminated by wideband spectral light and the ACA exists, then the frequency bandwidth may become narrower than the monochromatic case, and the position of image sensor can be relocated to balance frequency bandwidth among all wavelengths.     

Ilaprazole metabolites,ilaprazole sulfone and ilaprazole sulfide decreased the affinity of ilaprazole to bovine serum albumin

The interaction of ilaprazole (IPZ), ilaprazole sulfone (IPZO) and ilaprazole sulfide (IPZI) with bovine serum albumin (BSA), and the effect of IPZO and IPZI on the interaction of IPZ with BSA have been investigated by fluorescence, synchronous fluorescence, ultraviolet–visible (UV–vis), Fourier transform infrared spectroscopy (FT-IR) and circular dichroism (CD). The results indicated that IPZ, IPZO and IPZI had a strong ability to quench the intrinsic fluorescence of BSA, and the binding affinities were significantly affected by structures in the order IPZ>IPZO>IPZI, while the van der Waals force and hydrogen bond played major roles in their binding with BSA. The analysis of synchronous fluorescence, FT-IR and CD spectra showed the change in secondary structure of BSA upon interaction with IPZ, IPZO or IPZI. Site marker competitive experiments indicated that their binding to BSA primarily took place in subdomain IIA. The presence of IPZO and IPZI decreased the quenching constants of IPZ with BSA by about 68.4% and 95.1%, respectively, which possibly resulted from the existence of competitive binding between IPZ and its metabolites with BSA. However, IPZO and IPZI did not change the quenching mechanism of IPZ with BSA, while all the fluorescence quenching was initiated by static quenching procedure combined with non-radiative energy transfer. Our results may have relevant insight into IPZ's bioavailability and efficacy affected by its metabolites.     

Propagation and modulation of Airy beams through a four-level electromagnetic induced transparency atomic vapor

We study the propagation properties of an Airy beam through a four-level electromagnetic induced transparency (EIT) atomic vapor. The analytical expression for the Airy beam passing through the ABCD optical system of the EIT vapor is deduced and employed to analyze the propagation characteristics of the beam. It is shown that both the deflection position and the intensity of the Airy beam can be modulated by the Rabi frequency of the control light. Such a tunable optical behavior may have some potential applications in medicine science.     

太阳极紫外成像光谱仪光学系统设计与分析

针对太阳极紫外成像光谱仪的应用目的与工作环境,设计了一种太阳极紫外成像光谱仪的光学系统.该系统由望远系统、狭缝、光栅与探测器组成.望远系统采用离轴WolterⅡ型结构,入射光掠入射进入系统,具有光谱范围宽、稳定性高、克服恶劣空间环境能力强等优点.扫描镜采用平面反射镜,成像质量不随扫描角的改变而改变.分光光栅采用超环面3 600lines/mm变间距光栅,与超环面等间距光栅相比,具有成像质量高、光谱分辨率高、缩短系统长度的优势.工作波段为17.0～21.0nm,可满足探索温度在5.8≤log T≤6.3区间的宁静日冕的需要.视场为1 228″×2 400″,空间分辨率达到0.8arc second/pixel,光谱分辨率约为0.001 98nm/pixel,总长度不超过2.5m.计算了望远系统的理论有效面积,给出了望远系统的成像质量与实际的视场.系统整体的成像质量、光栅的谱线弯曲与谱带弯曲,均满足实际应用要求.     

太阳能电池板在剪草机上应用的研究

利用太阳能电池板作为能源装置,电机为剪草的动力装置的太阳能剪草机工作时安静无污染更适合未来社会对绿色生活的要求。     

Application of surface-enhanced Raman in skin cancer by plasma

We have developed a mouse squamous cell carcinomas (SCC) model by diniethylbenzanthracene (DMBA) and ultraviolet (UVB). A silver colloid as SERS-active substrates is used for detecting the blood plasma of mouse. The relative intensity of the band at 942 and 1499 cm⁻¹ is higher in SCC model than in healthy one. Therefore, it can be used as an important “fingerprint” in order to diagnose these diseases. Results show us how to get high signal-to-noise ratio of biological macromolecules surface-enhanced Raman scattering spectra in blood plasma. And also offer useful help for understanding the rich molecular structure information in biological tissues. It provides a molecular spectroscopy way for early detection of disease in blood plasma.     

Charmless Bs→PP, PV, VV decays based on the six-quark effective Hamiltonian with strong phase effects II

We provide a systematic study of charmless B _s →PP, PV, VV decays (P and V denote pseudoscalar and vector mesons, respectively) based on an approximate six-quark operator effective Hamiltonian from QCD. The calculation of the relevant hard-scattering kernels is carried out, the resulting transition form factors are consistent with the results of QCD sum-rule calculations. By taking into account important classes of power corrections involving “chirally enhanced” terms and the vertex corrections as well as weak annihilation contributions with non-trivial strong phase, we present predictions for the branching ratios and CP asymmetries of B _s decays into PP, PV and VV final states, and also for the corresponding polarization observables in VV final states. It is found that the weak annihilation contributions with non-trivial strong phase have remarkable effects on the observables in the color-suppressed and penguin-dominated decay modes. In addition, we discuss the SU(3) flavor symmetry and show that the symmetry relations are generally respected.