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41.
Nitrogen‐rich double salt ammonium 3,4‐diamino‐1,2,4‐triazoliumstyphnate (NH4 · DATr · TNR) ( 2 ) with good thermal stability was successfully synthesized by reacting 3,4‐diamino‐1,2,4‐triazolium chloride aqueous solution with styphnic acid methanol solution under the reaction medium of aqueous ammonia. The title double salt was characterized by elemental analysis (EA), Fourier transformation infrared spectrum (FT‐IR), and X‐ray single‐crystal diffraction. It crystallizes in the monoclinic crystal system with space group P21/n. Its density is 1.780 g · cm–3. Compound 2 is thermal stable below 200 °C by the differential scanning calorimetry (DSC) test. The non‐isothermal kinetics parameters were calculated by the Kissinger's method and Ozawa‐Doyle's method, respectively. In addition, compound 2 showed low friction and impact sensitivities.  相似文献   
42.
MiniSTR loci have been demonstrated to be an effective approach in recovering genetic information from degraded specimens, because of the reduced PCR amplicon sizes which improved the PCR efficiency. Eight non‐combined DNA index system miniSTR loci suitable for the Chinese Han Population were analyzed in 300 unrelated Chinese Han individuals using two novel five fluorescence‐labeled miniSTR multiplex systems(multiplex I: D10S1248, D2S441, D1S1677 and D9S2157; multiplex II: D9S1122, D10S1435, D12ATA63, D2S1776 and Amelogenin). The allele frequency distribution and forensic parameters in the Chinese Han Population were reported in this article. The Exact Test demonstrated that all loci surveyed here were found to be no deviation from Hardy–Weinberg equilibrium. The accumulated power of discrimination and power of exclusion for the eight loci were 0.999999992 and 0.98, respectively. The highly degraded DNA from artificially degraded samples and the degraded forensic case work samples was assessed with the two miniSTR multiplex systems, and the results showed that the systems were quite effective.  相似文献   
43.
具有反铁磁相互作用的双铁磁链中的非线性激发   总被引:3,自引:2,他引:3  
采用双子格模型和相干态表示,研究了链与链之间存在反铁磁相互作用的双铁磁链系统中的非线性激发的性质,得到了孤子的宽度,能量及有效质量。结果表明在不同情况下的各向异性双铁磁链中可以激发拓扑性孤子或非拓性孤子或非拓生反孤子。  相似文献   
44.
该文应用Hodge分解定理,得到了非齐次A—调和方程组-Di(A^ij(x,Du)) Difj(i(x)=0,j=1,…,m的很弱解是弱解,进一步,利用Morrey空间法与Campanato空间法以及齐次化方法,作者得出了该方程的很弱解是局部Hoelder连续的,并且得出了Hoelder连续指数μ与λ之间的多值函数关系式.  相似文献   
45.
Ultracold atomic physics experiments offer a nearly ideal context for the investigation of quantum systems far from equilibrium. We describe three related emerging directions of research into extreme non‐equilibrium phenomena in atom traps: quantum emulation of ultrafast atom‐light interactions, coherent phasonic spectroscopy in tunable quasicrystals, and realization of Floquet matter in strongly‐driven lattice systems. We show that all three should enable quantum emulation in parameter regimes inaccessible in solid‐state experiments, facilitating a complementary approach to open problems in non‐equilibrium condensed matter.  相似文献   
46.
In this paper, we propose a compensated pixelwise calibration that integrates the effects of the camera housing temperature. The results of this calibration are compared on black body images to classic two points Non Uniformity Correction based calibrations, compensated or not. It is shown that the proposed approach leads to a significant improvement in the thermal resolution with a reduction in the mean error as well as the standard deviation. The approach is finally challenged on a real case measurement focusing on thermoelasticity. The gain in terms of accuracy measurement is highlighted by comparing the proposed calibration to classic calibrations and the scope of interest of this new calibration is discussed.  相似文献   
47.
The mechanical behavior of a partially saturated porous medium is addressed by means of a micro-to-macro reasoning. First, an estimate of the quadratic average over the solid phase of the equivalent shear strain is proposed. The latter is used in the framework of a nonlinear homogenization technique (‘modified secant’ method) in order to model the nonlinear poroelastic behavior in partially saturated conditions. The determination of the macroscopic strength criterion is then considered. Finally, the influence of membrane tension effects on strength is investigated. To cite this article: L. Dormieux et al., C. R. Mecanique 334 (2006).  相似文献   
48.
This Note presents an experimental vibro-acoustic set-up that aims to reproduce the energy pumping phenomenon between an acoustic medium and an essentially nonlinear oscillator. It shows a one-way irreversible transfer of energy between the first acoustic mode in a tube and a thin visco-elastic membrane. To cite this article: B. Cochelin et al., C. R. Mecanique 334 (2006).  相似文献   
49.
开挖过程的非线性理论分析   总被引:2,自引:2,他引:2  
本文从岩土介质力学非线性和变形破坏过程自组织非线性的角度对开挖过程岩土体非线性行为进行了探讨。以此为依据,分析了岩土从微观破坏、滑移面形成、直至整体变形破坏全过程的自组织发生机理,在此基础上,建立了伴随开挖过程岩土体变形破坏的非线性动力学描述方程。  相似文献   
50.
锚杆锚固质量无损检测的研究   总被引:1,自引:0,他引:1  
本文介绍了一种无损检测锚杆锚固质量的新技术。通过模型试验,分析了声频应力波在锚固体系中的反射相位特征和能量衰减变化规律,探讨了测定锚固力的无损拉拔试验,并将结果成功应用于潘一矿巷道锚杆锚固工程的施工质量检测。  相似文献   
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