强激光加载下高压液氘材料的电导率

液氘在高压下有丰富的电学光学性质。利用反射率和相对介电函数关系并从广义极化角度出发初步建立了计算低Z材料电导率的简易模型;在神光-Ⅱ装置上利用第九路激光冲击加载液氘材料并测量了其在强激光冲击下的高压状态参数和反射率。结合上述理论模型和实验,研究了高压下液氘的电离度和电导率。结果表明,液氘在约70 GPa时的电导率约为2.87105 (Wm)-1,已呈现出较为明显的金属电导特性。显然,冲击加载下液氘从绝缘分子态开始电离并向金属氘转变发生在更低的压强。     

Complete and Nondestructive Atomic Bell‐State Analysis Assisted by Inverse Engineering

A protocol for complete and nondestructive atomic Bell‐state analysis by using inverse engineering is presented. The setups for the Bell‐state analysis contain four atoms trapped in four separated cavities, respectively. The laser pulses designed by inverse engineering help in the manipulation of the transitions of atoms in a robust manner. By using the protocol, the information for distinguishing four Bell states of two information‐carrying atoms is encoded on two auxiliary atoms. Therefore, the four Bell states can be distinguished without being destroyed by detecting the states of the two auxiliary atoms. Moreover, as shown by the numerical simulations, the protocol has high successful probabilities to distinguish four Bell states when decoherence is considered. Thus, the protocol may provide some helpful perspectives for the quantum information tasks based on Bell states.     

Ankyrin repeat and SOCS box containing protein 4 (Asb-4) colocalizes with insulin receptor substrate 4 (IRS4) in the hypothalamic neurons and mediates IRS4 degradation

Background

Cigarette smoking enhances the risk of stroke. However, the underlying molecular mechanisms are largely unknown. The present study established an in vivo rat secondhand cigarette smoking (SHS) model and examined the hypothesis that SHS upregulates endothelin receptors with increased cerebrovascular contraction via the Raf/extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinases (MAPK) pathway.

Results

Rats were exposed to SHS for up to 8 weeks. The cerebral artery vasoconstriction was recorded by a sensitive myograph. The mRNA and protein expressions for endothelin receptors in cerebral arteries were studied by real-time PCR and Western blot. Compared to fresh air exposed rats, cerebral arteries from SHS rats exhibited stronger contractile responses (P < 0.05) mediated by endothelin type A (ET_A) receptors. The expressions of mRNA and protein for ET_A receptors in the cerebral arteries from SHS rats were higher (P < 0.05) than that in control. SHS did not affect endothelin type B (ET_B) receptor-mediated contractions, mRNA or protein levels. The results suggest that SHS upregulates ET_A, but not ET_B receptors in vivo. After SHS exposure, the mRNA levels of Raf-1 and ERK1/2, the protein expression of phosphorylated (p)-Raf-1 and p-ERK1/2 were increased (P < 0.05). Raf-1 inhibitor, GW5074 suppressed the enhanced ET_A receptor-mediated contraction, mRNA and protein levels induced by SHS. In addition, GW5074 inhibited the SHS-caused increased mRNA and phosphorylated protein levels of Raf-1 and ERK1/2, suggesting that SHS induces activation of the Raf/ERK/MAPK pathway.

Conclusions

SHS upregulates cerebrovascular ET_A receptors via the Raf/ERK/MAPK pathway, which provides novel understanding of mechanisms involved in SHS-associated stroke.     

Creep deformation measurement using quartz optical fiber

This paper describes an optical system for high temperature creep strain measurement using quartz optical fiber, super long working distance microscope and digital image processing techniques. In this system one end of the quartz optical fibers is arrayed in a small area on the specimen surface and the other end is illuminated by a laser beam. The fiber ends on the specimen surface form the spot array. The small optical spots on the specimen are tracked by a CCD camera and the images are processed by digital image processing software. The diameter of each quartz fiber is 100 μm and the fibers can be arrayed in a small area. The local strains are determined by measuring the variety of relative distance between two spots. Experimental results of local creep strain on the welding joints of 15CrMo and HK40 at 850°C are obtained.     

Spectral structure of CuBr vapor laser lines

The atomic density, the buffer gas pressure, and the voltage dependence of the 510.6 nm laser line shape and its temporal evolution emitted from a Cu/CuBr vapor laser are measured. It is found that the monochromaticity of these laser lines can be improved greatly at a relative high buffer gas pressure. The temporal evolution of the line shape offers a stereoscopic view of a laser pulse. The sequence of appearance of the peaks of the line shape is governed by the intensity of the hyperfine component of the copper line.     

Lp径向Blaschke-Minkowski同态的Lp对偶几何表面积

2006年,Schuster提出了径向Blaschke-Minkowski同态的概念.随后,汪卫等人将其推广到L_p径向Blaschke-Minkowski同态.本文结合L_p对偶几何表面积,建立了L_p径向Blaschke-Minkowski同态的若干不等式,包括Brunn-Minkowski型不等式和单调不等式.并给出了L_p径向Blaschke-Minkowski同态的Busemann-Petty问题的肯定和否定形式.     

Sulfur-Containing Bent N-Heteroacenes

A series of novel sulfur-containing bent N-heteroacenes were constructed and characterized by NMR and UV/Vis spectroscopy, cyclic voltammetry, and single-crystal X-ray diffraction. By introducing sulfur-containing groups (thio, sulfinyl, and sulfonyl) into bent azaacenes, their electronic delocalization was improved and frontier energy levels were modulated. The target products displayed tunable optical and electronic properties through altering the valence of sulfur and fused length of the azaacenes. For the first time, typical products were utilized as organic field effect transistor materials, affording promising results.     

A torsion–translational vibration isolator with quasi-zero stiffness

Nonlinear Dynamics - In this paper, a torsion–translational quasi-zero-stiffness (TT QZS) isolator with convex ball–roller mechanisms was proposed to attenuate the torsion and...