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91.
Ronald F. Bruner 《International Journal of Theoretical Physics》2009,48(9):2704-2714
It is shown that if a volume element V, of space is assumed to have intrinsic energy E, then basic principles of mechanics, thermodynamics and special relativity lead to the equation of state: E=pV, where p is the pressure. When this equation of state is incorporated in the Einstein equations it leads to the prediction that the
orbital speed of matter circling a visible galaxy embedded in a spherical galactic halo should be relativistic, in disagreement
with observations. However, it also leads directly to the interesting notion that the inertial mass of such a medium can be
understood as a resistance to being compressed via Lorentz contraction. It is then shown that the mathematical structure of
thermodynamics suggests another plausible definition of pressure if we allow for the possibility that the intrinsic energy
of spacetime may not be described by the same work-energy relationship as ordinary matter. This additional possibility leads
to the equation of state: E=−pV. While both of these equations of state describe forms of energy that are quite unlike ordinary energy, neither alone is
able to account for observed rotational velocity curves of matter orbiting visible galaxies. Therefore, the possibility that
space has two distinct components of energy is investigated. This results in a plausible, two-component equation of state
in which the former equation of state is tentatively identified as the “dark matter” (DM) component, the latter as the “dark
energy” (DE) component. The effective equation of state of space, accounting for the presence of both components, may then
be written in the form: p=w
ε, where ε is the total energy density, p the total pressure, and w represents the fractional excess of DM over DE (and therefore satisfies: −1≤w≤+1). Given the wide range of possible spacetime properties implied by this equation it appears to be a viable candidate for
explaining observations presently attributed to the presence of both DM and DE. Specifically, the static, spherically symmetric
solution of Einstein’s field equations, neglecting effects of ordinary matter, predicts the inverse r
2 distribution of intrinsic space energy required to explain observed constant rotational velocity curves for matter in circular
orbits around visible galaxies embedded within spherically symmetric galactic halos. The proposed equation of state is also
capable of describing regions of space undergoing accelerated expansion as regions where DE is dominant (i.e., w<−1/3). 相似文献
92.
93.
94.
J. Borkowska-Burnecka W. ?yrnicki E.H. Fink 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(9):1599-1606
Rotational and vibrational temperatures of electronically excited BiN radicals in a low-pressure Bix+N/N2*/N2+Ar chemiluminescent flame have been deduced from high-resolution Fourier-transform emission spectra. Bands of three electronic transitions, a3Σ+(a11)→X1Σ+(X0+), b5Σ+(b10+)→X1Σ+(X0+), and b5Σ+(b10+)→a 3Σ+(a11), were analysed to determine the optical temperatures in the a3Σ+(a11) and b5Σ+(b10+) states. The rotational temperatures characterising the rotational populations in the a11, v=0 and 1 states were determined from the a1→X, 0-2, 0-3, 0-4, 1-1, and 1-2 bands. The b1→X, 0-8 and 0-11 bands, and the b1→a1, 0-0 bands served to determine the rotational temperature of the radicals in the b10+, v=0 state. The temperatures derived from the various bands and transitions were well consistent and the mean rotational temperature was determined to be 353±18 K, which is close to the translational temperature of the gas.Vibrational temperatures of the radicals in the a11 and b10+ states were derived from band intensities of the a1→X and from the b1→X as well as b1→a1 systems, respectively. The Franck-Condon factors needed were calculated with RKR potentials deduced from literature values of the rotational and vibrational constants in the three states involved. The a11 vibrational temperature (336±21 K) was close to the rotational temperature, while the b10+ vibrational temperature (438±36 K) differed, likely due to the previously observed perturbation of the b10+ state. 相似文献
95.
96.
K(5P)与H2反应产生KH(Х1Σ+)的ν″=0~3振动能级,泛频激发KH至ν″=17高位振动态。通过测定KH(ν″=17,3)与CO2碰撞过程中振动能的时间分辨分布(即Tν的变化过程),研究了高低振动态碰撞传能的不同特点。对于KH(ν″=17),振动温度Tν的变化分为三个阶段:第一阶段(0~5μs)Tν迅速下降,能量应主要转移至CO2(0001)振动态或(0000)高位转动态;第二阶段(5~20μs)Tν仅稍有下降,向CO2振动态及高位转动态的能量转移已结束;第三阶段(20μs后)Tν虽然缓慢但明显下降,表明向CO2低转动态及平动能的转移加速。对于KH(ν″=3),Tν的变化只分为两个阶段:第一阶段(0~10μs)的共振V-R过程迅速降低了振动温度;第二阶段(10~80μs)Tν有一个缓慢下倾,只能转移到很低的转动态和小的平动能。这些结果表明了振动激发态分子与基态分子碰撞中仅用单一速率系数不能正确揭示复杂平衡过程的本质,不同的阶段应该用不同的速率系数来描述。利用瞬时吸收技术得到CO2(0000)和(0001)的原生态转动布居分布,通过速率方程分析,得到平衡过程中不同阶段的速率系数。 相似文献
97.
Fengman Liu Binbin Yang Baoxia Li Haidong Wang Haiyun Xue Yuan Lu 《Fiber and Integrated Optics》2014,33(1-2):17-25
AbstractThe bi-directional data rate is investigated of an eight-channel × 10-Gbps optical transceiver with a size of 15 mm × 15 mm × 6 mm and ball grid array package form that was designed and fabricated. A passive optical coupling method is designed based on a coupling lens array, which is transformed to substrate through a carrier. This electrical performance is characterized through a 3D full wave simulation and shows great advantages compared with traditional pluggable optical transceivers. Experimental eye diagram measurement in loop-back mode via a 2-m-long multi-mode fiber array shows an eye width of 51.984 ps at a bit-error rate order of 10?12, which proves the transceiver's ability for 10.3125-Gbps data transmission. 相似文献
98.
A.V. Potapov L.A. Surin S. Schlemmer T.F. Giesen 《Journal of Molecular Spectroscopy》2011,270(2):116-119
The pure rotational spectrum of the Ne–CO van der Waals complex has been measured in the frequency range of 208–230 GHz by using the Cologne supersonic jet spectrometer for terahertz applications (SuJeSTA). Eleven new transitions were assigned as belonging to two R- and two Q-branches of the K = 2–1 subband detected for the first time in the ground vibrational state of CO (νCO = 0). Improved molecular parameters of the Ne–CO complex were obtained which allowed for a sensitive test of the available intermolecular potential energy surfaces of the Ne–CO system. 相似文献
99.
安装于紫金山天文台盱眙观测站用以观测近地天体的大型Schmidt望远镜,采用了平场Schmidt光学系统,改正镜通光口径为1m,球面反射镜口径为1.2m,焦距为1.8m,接收器用了4K×4K的高灵敏度CCD。本文叙述了该仪器光轴调整的方法及调整后观测获得的初步结果。叙述了望远镜光轴校正方法、校正结果、CCD靶面的调整及望远镜极轴高度、方位的调整及相应的照片。经实际观测的结果是:露光1s可拍到18等星;露光4s可拍到19.3等星;露光20s可拍摄到21.2等星。 相似文献
100.
The accurate measurement of small spin–spin coupling constants in macromolecules dissolved in a liquid crystalline phase is important in the context of molecular structure investigation by modern liquid state NMR. A new spin-state-selection filter, DIPSAP, is presented with significantly reduced sensitivity to J-mismatch of the filter delays compared to previously proposed pulse sequences. DIPSAP presents an attractive new approach for the accurate measurement of small spin–spin coupling constants in molecules dissolved in anisotropic solution. Application to the measurement of 15N–13C′ and 1HN–13C′ coupling constants in the peptide planes of 13C, 15N labeled proteins demonstrates the high accuracy obtained by a DIPSAP-based experiment. 相似文献