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41.
Interactions of delta shock waves for the relativistic Chaplygin Euler equations with split delta functions
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In this article, we are concerned with the interactions of delta shock waves with contact discontinuities for the relativistic Euler equations for Chaplygin gas by using split delta functions method. The solutions are obtained constructively and globally when the initial data consists of three piecewise constant states. The global structure and large time‐asymptotic behaviors of the solutions are analyzed case by case. During the process of the interaction, the strengths of delta shock waves are computed completely. Moreover, it can be found that the Riemann solutions are stable for such small perturbations with special initial data by letting perturbed parameter ε tends to zero. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
42.
Equalizer technology followed by DIGE‐based proteomics for detection of cellular proteins in artificial peritoneal dialysis effluents
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Anton Michael Lichtenauer Rebecca Herzog Silvia Tarantino Christoph Aufricht Klaus Kratochwill 《Electrophoresis》2014,35(10):1387-1394
Peritoneal dialysis effluent (PDE) represents a rich pool of potential biomarkers for monitoring disease and therapy. Until now, proteomic studies have been hindered by the plasma‐like composition of the PDE. Beads covered with a peptide library are a promising approach to remove high abundant proteins and concentrate the sample in one step. In this study, a novel approach for proteomic biomarker identification in PDEs consisting of a depletion and concentration step followed by 2D gel based protein quantification was established. To prove this experimental concept a model system of artificial PDEs was established by spiking unused peritoneal dialysis (PD) fluids with cellular proteins reflecting control conditions or cell stress. Using this procedure, we were able to reduce the amount of high abundant plasma proteins and concentrate low abundant proteins while preserving changes in abundance of proteins with cellular origin. The alterations in abundance of the investigated marker for cell stress, the heat shock proteins, showed similar abundance profiles in the artificial PDE as in pure cell culture samples. Our results demonstrate the efficacy of this system in detecting subtle changes in cellular protein expression triggered by unphysiological stress stimuli typical in PD, which could serve as biomarkers. Further studies using patients’ PDE will be necessary to prove the concept in clinical PD and to assess whether this technique is also informative regarding enriching low abundant plasma derived protein biomarker in the PDE. 相似文献
43.
Yuanpeng Liang Bin Xiang Chao Liu Xiangdong Zhou Dan Wang Shan Song Genghua Bai Qi An Quehong Huang Shujun Chen Xuefeng Wei 《Tetrahedron》2014
Novel fluorine-containing ultraviolet absorbers (FBPs) with low surface energy were successfully synthesized based on 2,4-dihydroxy benzophenone (BP-1), and their structures were characterized by 1H NMR, 13C NMR, FTIR, and HRMS. UV absorption of FBPs was studied in 10−4 M dichloromethane (CH2Cl2), which demonstrated the superior UV absorption capability of FBPs (ca. ?=1.7×104 to 2.2×104 at λmax) over the matrix (?=1.7×104 at λmax). Quantum chemistry calculation was performed to investigate the stable structure and UV electronic absorption bands of FBPs. The surface chemistry information of high-chlorinated polyethylene (HCPE) coating films embedded with ultraviolet absorbers (UVAs) was given by X-ray photoelectron spectroscopy (XPS) and contact angle measurement. The results show that the surface enrichment capability of FBPs is remarkably better than traditional UVAs (including BP-1, BP-3, BP-12) because of the low surface energy properties of FBPs. 相似文献
44.
45.
强冲击下的物质变形、破坏及诱发的轻重介质混合问题,是内爆压缩科学和工程应用领域的研究重点.本文针对爆轰波对碰条件下的复杂加载动力学过程及其动载破坏形态特征,开展数值模拟研究与极曲线理论分析.设计了爆轰波对碰驱动平面锡飞层的计算模型,获得了爆轰加载动力学过程及波系相互作用物理图像,分析了锡飞层对碰区自由表面速度历史的典型特征.给出了锡飞层中折射激波对碰发生马赫反射的临界条件,解读了三波结构的传播行为,阐明了对碰区内存在"一维正冲击"区域,一维区外存在单次斜冲击向两次斜冲击过渡的复杂加载动力学过程,提出了对碰区冲击动力学模型,揭示了影响对碰区动载行为特征的机理.数值模拟结果与极曲线理论分析结果相互印证,符合较好.本文的研究成果,将为深入理解和解读对碰区特殊的物质破坏及混合现象提供重要的理论支撑. 相似文献
46.
47.
研究表明,立方氧化锆可作为冲击波实验中的窗口材料.为了使得该材料在常态下保持结构稳定,需添加稳定剂——氧化钙.然而,掺杂会导致其在29 GPa的冲击压力下从立方转变为斜方Ⅱ结构相.因此,该材料在冲击压缩下的电子结构和光学吸收性质以及作为光学窗口的适用压力范围是值得研究的重要问题.本文运用第一性原理的方法,分别计算了在100 GPa范围内两种结构氧化锆的电子结构和光学吸收性质.结果表明:(1)在立方结构相区,冲击压力将导致其吸收边蓝移,而在斜方Ⅱ结构相区,却使得其吸收边红移;(2)在立方结构相区,掺杂将引起能隙变窄(吸收边红移),但对于斜方II相区,却导致能隙变宽(吸收边蓝移);(3)冲击结构相变使得能隙变窄,吸收边红移.本文数据建议,掺氧化钙的立方氧化锆在95GPa的冲击压力范围内可作为光学窗口材料. 相似文献
48.
We realized a series of experiments to study the physics of laser–plasma interaction in an intensity regime of interest for the novel “Shock Ignition” approach to Inertial Fusion. Experiments were performed at the Prague Asterix Laser System laser in Prague using two laser beams: an “auxiliary” beam, for pre-plasma creation, with intensity around 7?×?1013?W/cm2 (250?ps, 1ω, λ?=?1315?nm) and the “main” beam, up to 1016?W/cm (250?ps, 3ω, λ?=?438?nm), to launch a shock. The main goal of these experiments is to study the process of the formation of a very strong shock and the influence of hot electrons in the generation of very high pressures. The shock produced by the ablation of the plastic layer is studied by shock breakout chronometry. The generation of hot electrons is analyzed by imaging Kα emission. 相似文献
49.
Jiri Ullschmied 《辐射效应与固体损伤》2015,170(4):278-289
The Prague Asterix Laser System (PALS) Research Infrastructure (RI) in Prague, one of only four kJ-class laser facilities in EU, has been offering its beam time to European researchers for already 14 years, since 2004 in the framework of the LASERLAB-Europe consortium. Till June 2014, the PALS RI has provided 4313 experimental days for a total of 41 projects with 303 international users from 42 different research institutions. Its principal experimental facility is a terawatt sub-ns iodine laser (1315?nm) with an optional plasma-based zinc XUV laser (21.2?nm), and an auxiliary Ti:Sapphire fs laser (1?J, 70?fs) exploited for femtosecond plasma probing and experiments with synchronised femtosecond and sub-nanosecond laser pulses at mean laser intensities of up to 30?PW/cm2. The lasers are equipped with several target facilities and rich sets of instruments for both active and passive plasma diagnostics. The PALS main research areas include development and applications of secondary laser sources of high-energy ions and both coherent and non-coherent high-intensity XUV radiation, laboratory astrophysical and inertial fusion-relevant studies. In this paper, the main results having been achieved at PALS in the framework of LASERLAB-EUROPE international access activities during the last four years are highlighted. 相似文献
50.
Lysosomal pH Rise during Heat Shock Monitored by a Lysosome‐Targeting Near‐Infrared Ratiometric Fluorescent Probe
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Dr. Qiongqiong Wan Prof. Dr. Suming Chen Prof. Dr. Wen Shi Lihong Li Prof. Dr. Huimin Ma 《Angewandte Chemie (International ed. in English)》2014,53(41):10916-10920
Heat stroke is a life‐threatening condition, featuring a high body temperature and malfunction of many organ systems. The relationship between heat shock and lysosomes is poorly understood, mainly because of the lack of a suitable research approach. Herein, by incorporating morpholine into a stable hemicyanine skeleton, we develop a new lysosome‐targeting near‐infrared ratiometric pH probe. In combination with fluorescence imaging, we show for the first time that the lysosomal pH value increases but never decreases during heat shock, which might result from lysosomal membrane permeabilization. We also demonstrate that this lysosomal pH rise is irreversible in living cells. Moreover, the probe is easy to synthesize, and shows superior overall analytical performance as compared to the existing commercial ones. This enhanced performance may enable it to be widely used in more lysosomal models of living cells and in further revealing the mechanisms underlying heat‐related pathology. 相似文献