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1.
Thermodynamics is developed for a class of thermo-hypo-elastic materials. It is shown that materials of this class obey the laws of thermodynamics, but are not elastic.
Table of Symbols
Latin Letters A ijkl tensor-valued function of t ij appearing in hypo-elastic constitutive relation - B ijkl another tensor-valued function. See equation (4.2) - B the square of - d ij rate of deformation tensor - d ij deviator of rate of deformation - f, k functions of pressure, p - g, h functions of the invariant - p pressure - q i heat flux vector - s ij stress deviator - ij co-rotational derivative of stress deviator - t time - t 1 t 2 specific values of time - t ij stress tensor - t ij 0 a specific value of stress - T Temperature - T 0 a specific value of temperature - u i velocity - V(t) a material volume as a function of time, t - V 0 a material volume at a reference configuration - W work (W = work done in a deformation—section 5) Sript Letters Specific internal energy - Specific Helmholtz free energy - G Specific Gibbs function Greek Letters an invariant of the stress deviator—see eq. (2.4) - ij kroneker delta - (W = work done in a deformation—section 5) - specific entropy - hypo-elastic potential - hypo-elastic potential - mass density - 0 mass density in a reference configuration - specific volume = 1/ - a function of p - ijkl a constant tensor—see eq. (2.5) - –G/ - ij rate of rotation tensor This work is dedicated to Jerald L. Ericksen, without whose influence it would not have been possible 相似文献2.
3.
The predicted, but as yet unobserved, intradonor absorption spectrum of the hydrogenic-like donors in CdF2 crystals is presented. The role of phonon coupling in these spectra is discussed. From the data on the insulator-semiconductor transition in CdPbF2 it is concluded that the dominant factor in convertibility of CdF2 to a semiconducting state is its electron affinity, the largest among the fluorites (x≈4 eV). 相似文献
4.
Jeremy Bernstein 《Physics in Perspective (PIP)》2010,12(1):36-50
I discuss the origin of the idea of making a fusion (hydrogen) bomb and the physics involved in it, and then turn to the design
proposed for one by the unlikely collaborators John von Neumann and Klaus Fuchs in a patent application they filed at Los
Alamos in May 1946, which Fuchs passed on to the Russians in March 1948, and which with substantial modifications was tested
on the island of Eberiru on the Eniwetok atoll in the South Pacific on May 8, 1951. This test showed that the fusion of deuterium
and tritium nuclei could be ignited, but that the ignition would not propagate because the heat produced was rapidly radiated
away. Meanwhile, Stanislaw Ulam and C.J. Everett had shown that Edward Teller’s Classical Super could not work, and at the
end of December 1950, Ulam had conceived the idea of super compression, using the energy of a fission bomb to compress the
fusion fuel to such a high density that it would be opaque to the radiation produced. Once Teller understood this, he invented
a greatly improved, new method of compression using radiation, which then became the heart of the Ulam–Teller bomb design,
which was tested, also in the South Pacific, on November 1, 1952. The Russians have freely acknowledged that Fuchs gave them
the fission bomb, but they have insisted that no one gave them the fusion bomb, which grew out of design involving a fission
bomb surrounded by alternating layers of fusion and fission fuels, and which they tested on November 22, 1955. Part of the
irony of this story is that neither the American nor the Russian hydrogen-bomb programs made any use of the brilliant design
that von Neumann and Fuchs had conceived as early as 1946, which could have changed the entire course of development of both
programs. 相似文献
5.
A complete set of addition laws for incomplete Edwards curves 总被引:1,自引:0,他引:1
Edwards curves were the first curves shown to have a complete addition law. However, the completeness of the addition law depends on the curve parameters and even a complete Edwards curve becomes incomplete over a quadratic field extension. This paper covers arbitrary Edwards curves and gives a set of two addition laws that for any pair of input points P1, P2 produce the sum P1+P2. 相似文献
6.
固相萃取-毛细管柱气相色谱-质谱测定土壤和蔬菜中三唑酮残留量 总被引:3,自引:0,他引:3
提出固相萃取分离,毛细管柱气相色谱和质谱联用法测定土壤及蔬菜中三唑酮的残留量.试样用乙腈提取,所得提取液在80℃吹氮至近干,并加正己烷2 mL溶解残渣.此溶液流经填充酸性氧化铝的固相萃取小柱,用正己烷-丙酮(2+1)混合溶剂淋洗小柱,使土壤样品中存在的硫磺与需测定的三唑酮分离.用正己烷一丙酮(1+3)混合溶剂将三唑酮从小柱上解吸洗下,所得洗出液蒸发浓缩,用正己烷定容为5.0 mL供GC-MS分析用.测定中用三唑酮标准溶液制备浓度范围在0.006~1.44 mg·L-1之间的标准曲线.方法的检出限(3S/N)为0.001 mg·kg-1.在3个浓度水平上对方法的回收及精密度作了试验,测得其回收率及相对标准偏差(n=5)依次在84%~92 9,5及1.93%~4.04%之间. 相似文献
7.
A. Tamion C. Raufast E. Bonet V. Dupuis T. Fournier T. Crozes E. Bernstein W. Wernsdorfer 《Journal of magnetism and magnetic materials》2010,322(9-12):1315-1318
Technological improvements require the understanding of dynamical magnetization reversal processes at the nanosecond time scales. In this paper, we present the first magnetization reversal measurements performed on a single cobalt cluster (counting only a thousand of spins), using the micro-superconducting quantum interference device (SQUID) technique by applying a constant magnetic field combined with a radio-frequency (RF) field pulse. First of all, we present the different technical steps necessary to detect the magnetic reversals at low temperature (T=35 mK) of a well-defined nanoparticle prepared by low energy clusters beam deposition (LECBD). We previously showed that the three-dimensional (3D)-switching Stoner-Wohlfarth astroid represents the magnetic anisotropy of the nanoparticle. Then, an improved device coupled with a gold stripe line, allow us to reverse such macrospin, using a RF pulse. A qualitative understanding of the magnetization reversal by non-linear resonance has been obtained with the Landau-Lifschitz-Gilbert (LLG) equation. 相似文献
8.
B. Josephson G. Jungner J. G. Reinhold D. W. Wilson L. Cuny Y. Abe S. Kawaguchi A. v. Christiani V. Anger O. Rosenheim R. Ehrström K. Täufel H. Thaler G. Widmann E. Kirk W. R. Bloor H. H. Williams B. N. Erickson I. Avrin S. S. Bernstein I. G. Macy G. Ellis L. A. Maynard R. N. Chopra A. C. Roy R. Feulgen H. Grünberg K. Imhäuser C. A. Grau V. Oliva E. Epstein H. Lieb 《Analytical and bioanalytical chemistry》1941,122(3-4):149-160
9.
Chhavi Bhardwaj Jerry F. Moore Yang Cui Gerald L. Gasper Hans C. Bernstein Ross P. Carlson Luke Hanley 《Analytical and bioanalytical chemistry》2013,405(22):6969-6977
Laser desorption postionization mass spectrometry (LDPI-MS) imaging is demonstrated with a 10.5 eV photon energy source for analysis and imaging of small endogenous molecules within intact biofilms. Biofilm consortia comprised of a synthetic Escherichia coli K12 coculture engineered for syntrophic metabolite exchange are grown on membranes and then used to test LDPI-MS analysis and imaging. Both E. coli strains displayed many similar peaks in LDPI-MS up to m/z 650, although some observed differences in peak intensities were consistent with the appearance of byproducts preferentially expressed by one strain. The relatively low mass resolution and accuracy of this specific LDPI-MS instrument prevented definitive assignment of species to peaks, but strategies are discussed to overcome this shortcoming. The results are also discussed in terms of desorption and ionization issues related to the use of 10.5 eV single-photon ionization, with control experiments providing additional mechanistic information. Finally, 10.5 eV LDPI-MS was able to collect ion images from intact, electrically insulating biofilms at ~100 μm spatial resolution. Spatial resolution of ~20 μm was possible, although a relatively long acquisition time resulted from the 10 Hz repetition rate of the single-photon ionization source. Figure
Neutral species laser desorbed from cocultured biofilms undergo single photon ionization by VUV radiation and resultant ions are detected by time-of-flight mass spectrometry 相似文献
10.
Ibtissam Elaaraj Safae ER. Raouan Asmae Nakkabi Bouchra Es-sounni Ibnsouda Koraichi Noureddine El moualij Mohammed Fahim 《印度化学会志》2022,99(5):100404
New metal complexes of (Zn(II), Co(II), Ni(II) and Cu(II)) based on the ligand 2-(thiophen-2-yl)-1-(thiophen-2-ylmethyl)-1H-benzo[d]imidazole] were synthesized, whose structures were determined with the different spectroscopic techniques 1H NMR,13C NMR, FT-IR, UV–Visible and by mass spectrometry. The thermal analysis was performed by TG-DTA. The antioxidant activity of the ligand and its complexes was evaluated by DPPH (2,2-diphenyl-1-picrylhydrazyl) method, in comparison with the synthetic antioxidant, ascorbic acid. The results obtained showed that the antioxidant activity of the ligand and its complexes is moderate and that the copper complex has a high activity that exceeds that of ascorbic acid. Antimicrobial activity of the ligand and its metal complexes was studied against two Gram-positive bacteria: Bacillus subtilis ILP1428B, Staphylococcus aureus CIP543154 and two Gram-negative bacteria: Pseudomonas aeruginosa ATCC27653, Escherichia coli CIP5412 (American Type Culture Collection)the activity data show that the metal complexes are more potent than the free ligand. 相似文献