蛋白质芯片技术及生物医学应用

蛋白质芯片技术是一种新型蛋白质分析技术。文章介绍了研究它的目的和意义，重点介绍它的研制过程和研究内容以及生物医学应用。

合金材料韧性断裂的表征、孔洞成核准则和断裂模型

<正> Ⅰ.引言 韧性断裂是合金材料失效的主要形式之一。早在19世纪下半叶,有人就开始注意到金属材料的韧性断裂是通过内部颈缩而发生的。本世纪50年代,Puttick通过一系列实验和分析,提出了韧性断裂的机制是由于在材料内部的夹杂物上形成孔洞。随后,越来越多的实验事实表明,合金材料的韧性断裂是在材料里的第二相粒子(夹杂物)上形成孔洞,随后孔洞生长、汇合这样一个过程。50年代以来,位错理论的发展,电子显微镜的诞生,断裂学科

Reissner型板裂纹尖端应力应变场及应力强度因子计算

本文采用考虑横向剪应变的Reissner理论,给出了含裂纹平板在弯曲情况下裂纹尖端应力应变场的一般解。作为算例,应用此展开式对于在对称和反对称情况下的有限尺寸板进行了应力强度因子计算并给出相应的曲线。

旋转是怎样使液体星分裂的——重评“金斯-达尔文双星分裂理论”

<正> 宇宙万物都在旋转,人类藉以生存的地球就有自旋,进动和公转,它一面自转、一面又和其他行星一起绕太阳公转,整个太阳系一面自转,一面又随银河系在宇宙空间中旋转,所有天体和天体系统都在旋转,天体的旋转是怎样开始的,又怎样演化?旋转到底在天体演化过程中起了什么作用?

高焓激波风洞自由流参数测量的数值重建

高焓风洞中参数测量本身受到高温非平衡效应影响,单纯依靠实验测量不足以确定详细的风洞自由流参数.本文以JF-10高焓激波风洞为背景,通过喷管-试验段-测量仪模型非平衡流场的连贯计算,开展自由流参数测量的数值重建.在比较分析测量仪模型绕流场的计算结果和实验测量值的基础上,结合喷管流场的数值模拟结果,共同确定高焓风洞的详细自由流参数.

Compact 120 TW Ti: sapphire laser system with a high gain final amplifier

A 120TW/36fs laser system based on Ti:sapphire chirped-pulse amplification (CPA) has been successfully established in our lab. The final four pass Ti:sapphire amplifier pumped by an energetic single-shot Nd:YAG-Nd:glass laser was designed and optimized. With 24J/8ns pump energy at 532 nm, 300 mJ/220 ps chirped pulse was amplified to 5.98 J in this amplifier, and a total saturated gain of similar to 20 was achieved. The focused intensity of compressed beam could reach to 10(20) W/cm(2) with the M-2 of similar to 2.0. (c) 2005 Elsevier Ltd. All rights reserved.

Generation of attosecond pulses in a system with permanent dipole moment

The generation of attosecond pulses in a two-level system with permanent dipole moment is investigated. It is shown due to the presence of permanent dipole moments, that the plateau of the high-order harmonic generation spectrum can be extended to X-ray range. Moreover, attosecond pulses with higher intensity can be synthesized by using both even and odd harmonics because of their quantum interference. (c) 2006 Elsevier B.V. All rights reserved.

Optical solitons in a four-level inverted-Y system

With one weak probe field and two strong pumping fields, the possibility of producing superluminal optical solitons is discussed in a lifetime-broadened inverted-Y atomic medium with proper parameters. As the group velocity of the solitons is larger than c, its occurrence can be controlled by modulating the intensities and the detunings of lasers.

Design and construction of a static tester for blue ray optical storage

Blue ray optical storage is one of the important trends in the area of information storage, and attracts a number of researchers. Static tester for blue ray optical storage plays an important role in storage media research. We designed and constructed a static tester, in which modularization makes it very convenient to expand function. Employment of modulation/demodulation technique weakens test error so as to increase test precision. Focus move mode and the nano-positioners facilitate the relocation of recording marks. Only one laser with wavelength 406.7 nm is used. In this paper, system design and characteristics are represented in detail, and some experimental results are also given to show that the static tester can perform successfully, acting as research platform for blue ray optical storage. (c) 2005 Elsevier GmbH. All rights reserved.

Structural and optical properties of YAG : Ce3+ phosphors by sol-gel combustion method

High-quality Ce3+-doped Y3Al5O12 (YAG:Ce3+) phosphors were synthesized by a facile sol-gel combustion method. In this sol-gel combustion process, citric acid acts as a fuel for combustion, traps the constituent cations and reduces the diffusion length of the precursors. The XRD and FT-IR results show that YAG phase can form through sintering at 900 degrees C for 2 h. This temperature is much lower than that required to synthesize YAG phase via the solid-state reaction method. There were no intermediate phases such as YAlO3 (YAP) and Y4Al2O9 (YAM) observed in the sintering process. The average grain size of the phosphors sintered at 900-1100 degrees C is about 40 nm. With the increasing of sintering temperature, the emission intensity increases due to the improved crystalline and homogeneous distribution of Ce3+ ions. A blue shift has been observed in the Ce3+ emission spectrum of YAG:Ce3+ phosphors with increasing sintering temperatures from 900 to 1200 degrees C. It can be explained that the decrease of lattice constant affects the crystal field around Ce3+ ions. The emission intensity of 0.06Ce-doped YAG phosphors is much higher than that of the 0.04Ce and 0.02Ce ones. The red-shift at higher Ce3+ concentrations may be Ce-Ce interactions or variations in the unit cell parameters between YAG:Ce3+ and YAG. It can be concluded that the sol-gel combustion synthesis method provides a good distribution of Ce3+ activators at the molecular level in YAG matrix. (c) 2005 Elsevier B.V. All rights reserved.