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991.
Tao Li Hai-tao Zhou Zhong-hua Li Yun-fei Bai Yuan Li Jiang-rui Gao Jun-xiang Zhang 《Frontiers of Physics in China》2009,4(2):209-213
The transmission spectrum of four-level atoms in a cavity is calculated. It is shown that the four separate peaks associated
with normal mode splitting and intra-cavity double dark states can be observed simultaneously. The position and intensity
of the four peaks can be controlled by the intensity of the third interacting light. Therefore, the enhancement of normal
mode splitting by a third coupling light of the intra-cavity four-level atoms is developed.
相似文献
992.
Nam‐Ho You Namiko Fukuzaki Yasuo Suzuki Yasuhiro Nakamura Tomoya Higashihara Shinji Ando Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2009,47(17):4428-4434
A highly refractive and transparent aromatic polyimide (PI) containing a selenophene unit has been developed. The PI was prepared by a two‐step polycondensation procedure from 2,5‐bis(4‐aminophenylenesulfanyl)selenophene (APSP) and 4,4′‐[p‐thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA), and shows high thermal stabilities, such as a relatively high‐glass transition temperature of 189 °C and 5% weight loss temperature (T5%) of 418 °C. The optical transmittance of the PI film at 450 nm is higher than 50%. The selenophene unit provides the PI with a refractive index of 1.7594, which is higher than corresponding PIs containing a thiophene or a phenyl unit because of the high polarizability per unit volume of the selenium atom. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4428–4434, 2009 相似文献
993.
Youngkyu Chang Song Yun Cho Lee B. Steely Harry R. Allcock 《Journal of polymer science. Part A, Polymer chemistry》2009,47(3):692-699
Amphilic triblock copolymers with varying ratios of hydrophilic poly[bis (methoxyethoxyethoxy)phosphazene] (MEEP) and relatively hydrophobic poly(propylene glycol) (PPG) blocks were synthesized via the controlled cationic‐induced living polymerization of a phosphoranimine (Cl3P?NSiMe3) at ambient temperature. A PPG block can function as either a classical hydrophobic block or a less hydrophobic component by varying the nature of a phosphazene block. The aqueous phase behavior of MEEP‐PPG‐MEEP block copolymers was investigated using fluorescence techniques, TEM, and dynamic light scattering (DLS). The critical micelle concentrations (cmcs) of MEEP‐PPG‐MEEP block copolymers were determined to be in the range of 3.7–16.8 mg/L. The mean diameters of MEEP‐PPG‐MEEP polymeric micelles, measured by DLS, were between 31 and 44 nm. The equilibrium constants of pyrene in these micelles ranged from 4.7 × 104 to 9.6 × 104. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 692–699, 2009 相似文献
994.
995.
Nico Reuvers David Spain Michael Golombok 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,346(1-3):16-19
Additives for improving the flow uniformity during secondary oil recovery are partially retained in the rock. The flow improval effects continue to be observed even when the chemical solution is succeeded by pure water. Considerable flushing with water is required before the old permeability of the rock is restored to its original higher level. This effect is extremely advantageous for the application to water flooding profiles in oil recovery. It makes possible an alternating water slug/chemical solution flooding program which further reduces the already relatively small amount of chemicals required in the operation. 相似文献
996.
High speed neutral clusters and mercury droplets from a gas jet impactor are allowed to collide with graphite surfaces. These collisions produce a variety of dislocations. One of the dislocations is a narrow dislocation band with atomic resolution. This band has two partial dislocations on the sides of a central region of abc structure. 相似文献
997.
998.
反射相移对光学玻璃电流传感器抗电磁干扰能力的影响 总被引:1,自引:0,他引:1
在光学玻璃电流传感器中,如果光线反射转向时在光的p,s分量之间引入反射相移,则会对该传感器的抗电磁干扰能力产生不良影响,本文对这种情况进行了理论上的分析,并给出了数值模拟和实验的结果。 相似文献
999.
在包含三能级原子的环形腔的输出光场中,观察到了由电磁感应透明(EIT)效应导致的动态非稳及混沌.该动态非稳及向混沌的过渡可以通过耦合光场而加以很好地控制.同时,由三能级EIT导致的原子相干改变了系统的吸收、色散及非线性效应,从而极大地增强了系统的动态非稳和混沌过渡特性.建立了一个理论模型来定量地解释观察到的现象. 相似文献
1000.
Norio Tsujioka Norio Ishizuka Nobuo Tanaka Takuya Kubo Ken Hosoya 《Journal of polymer science. Part A, Polymer chemistry》2008,46(10):3272-3281
We recently presented a short communication on the preparation of epoxy‐based monoliths possessing highly ordered structures by polymerization induced phase separation based on the spinodal decomposition. In this article, we describe in detail on reaction mechanisms and structural properties of the epoxy‐based monoliths with well‐controlled macropores in the micrometer range. We prepared epoxy‐based monoliths based on diglycidyl ether of bisphenol A, bis(4‐aminocyclohexyl)methane, and polyethylene glycol with a bicontinuous structure by in situ step‐growth polymerization. Different morphology of epoxy‐based monoliths could be obtained by changing formulation of monomers and porogenic solvents. Characterizations of their morphologies were performed using scanning electron microscopy, mercury intrusion porosimetry, small angle X‐ray scattering, and gas adsorption measurement (BET method). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3272–3281, 2008 相似文献