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981.
Yanhua Shih 《Frontiers of Physics》2007,2(2):125-152
One of the most surprising consequences of quantum mechanics is the entanglement of two or more distant particles. In an entangled EPR two-particle system, the value of the momentum (position) for neither single subsystem is determined. However, if one of the subsystems is measured to have a certain momentum (position), the other subsystem is determined to have a unique corresponding value, despite the distance between them. This peculiar behavior of an entangled quantum system has surprisingly been observed experimentally in two-photon temporal and spatial correlation measurements, such as “ghost” interference and “ghost” imaging. This article addresses the fundamental concerns behind these experimental observations and to explore the nonclassical nature of two-photon superposition by emphasizing the physics of 2 ≠ 1 + 1. 相似文献
982.
Arnost Reiser Hsiao-Yi Shih Tung-Feng Yeh Jian-Ping Huang 《Angewandte Chemie (International ed. in English)》1996,35(21):2428-2440
This year some twenty billion integrated circuits will be produced worldwide. Almost all (98%) of them will be made with a photosensitive varnish, the photo resist, that allows the transfer of a fine line-pattern from an original transparency onto a silicon wafer. This photoresist has two components: one is a novolak resin, a low molecular weight phenol–formaldehyde condensation polymer; the other is a diazonaphthoquinone derivative (DNQ), which is the photoactive part of the system. Novolak–diazoquinone resists have played a crucial role in the microminiaturization of electronics. They are photographic materials of extremely high resolution, able to define features as small as 0.25 μm. Although they are now an indispensible ingredient of modern computer technology, until quite recently their molecular mechanism was not understood. We report here on work at Polytechnic University in New York aimed at solving the mystery of these important and intriguing systems. The solution, in so far as it has revealed itself to us, is rather unique and quite unexpected. 相似文献
983.
本文报道在经氧气高温处理后的H-ZSM-5沸石所生成的多种开链及闭环的乙烯正离子基衍生物、利用计算机模拟了解在沸石孔洞内的化学吸附情形、同时帮助判定正确的超精细作用产生的非等价质子偶合常数,利用-乙烯正离子基的磁不对称性了解自由基与沸石产生的作用及离子-分子间的化学反应.本文提出一个新方程式,它利用分子的对称性来了解这些正离子自由基的非平面性的几何形状. 相似文献
984.
In order to study the difference on the equilibrium, spectral properties of copper(II) complexes of diamino diamide and diamino diamine, new tetradentate ligands, 4,7‐dimethyl‐4,7‐diazadecanediamide (4,7‐N,N′‐Me2‐L‐2,2,2) and 1,10‐diamino‐4,7‐dimethyl‐4,7‐diazadecane (4,7‐N,N′‐Me2‐3,2,3‐tet), have been synthesized. Synthetic procedures for these new ligands are described. Their protonation constants have been determined potentiometrically in 0.10 MKC1 at 25.0°C. The formation of their copper(II) complexes have been investigated quantitatively by the potentiometric technique and by the measurement of their electronic spectra. 相似文献
985.
Hydrogenated amorphous silicon (a-Si:H) thin films grown at 250°C on (1 0 0) crystalline substrate using plasma-enhanced chemical vapor deposition (PECVD) with SiH4/H2 gas flow ratio equal to 5/1 (sccm) are investigated by transmission electron microscopy. It is found that the thin film is totally amorphous when grown on a glass substrate. But when the substrate is changed to crystalline silicon, some crystalline grains are found embedded in the amorphous structure in certain regions even if the thickness of the film reaches 600 nm. It is suggested that the amorphous silicon film grown on a crystalline silicon substrate at a temperature of 250°C without heavy H2 dilution is a mixed network of a small amount of crystalline silicon and the major portion of amorphous silicon. 相似文献
986.
We show that the continuum shock profiles for dissipative difference schemes constructed in Part I are nonlinearly stable. It is shown first that the profiles have the conservation property, obtained as the limit of the discrete version for profiles with nearby rational, quasi‐Diophantine speeds. This allows us to formulate antidifferencing of the schemes and to apply a generalization of the pointwise approach for viscous conservation laws for the stability analysis. © 1999 John Wiley & Sons, Inc. 相似文献
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