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991.
This work is the first evaluation of environmental gamma exposure rates by the Nuclear Medicine Department at Lin Shin Hospital (LSH) in Taichung with Thermoluminescent dosimeter (TLD-100H) during the Fukushima Nuclear Power Plant (FNPP) accident. After the 9.0 MW strong earthquake hit northern Japan on March 11, 2011, a TLD-100H was used to monitor environmental kerma rate at Taichung (2,500 km away from northern Japan) from Mar-08 to Apr-09, 2011 and evaluated kerma rate due to global fallout of the sever FNPP accidents. Exposure rates varied widely among positions close to the PET/CT facility. Observed kerma rates of up to 4.12 ± 0.62 mSv mo−1 indicated an explicit, heavy leakage of photon through the PET/CT facility. No significant contributions were detected at Taichung, Taiwan. Hence, the health effect cause by the “extra radiation” from FNPP accidents is negligible. As this was a rare case of environmental monitoring during a nuclear power plant accident, its findings are of considerable significance.  相似文献   
992.
993.
Two novel sulfonate phenol ligands—3,3′‐di‐tert‐butyl‐2′‐hydroxy‐5,5′,6,6′‐tetramethyl‐biphenyl‐2‐yl 4‐X‐benzenesulfonate (X?CF3, LCF3 ‐H, and X?OCH3, LOMe ‐H)—were prepared through the sulfonylation of 3,3′‐di‐tert‐butyl‐5,5′,6,6′‐tetramethylbiphenyl‐2,2′‐diol with the corresponding 4‐substituted benzenesulfonyl chloride (1 equiv.) in the presence of excess triethylamine. Magnesium (Mg) complexes supported by sulfonate phenoxide ligands were synthesized and characterized structurally. The reaction of MgnBu2 with L‐H (2 equiv.) produces the four‐coordinated monomeric complexes ( LCF3 )2Mg ( 1 ) and ( LOMe )2Mg ( 2 ). Complexes 1 and 2 are efficient catalysts for the ring‐opening polymerization of ε‐caprolactone (ε‐CL) and trimethylene carbonate (TMC) in the presence of 9‐anthracenemethanol; complex 1 catalyzes the polymerization of ε‐CL and TMC in a controlled manner, yielding polymers with the expected molecular weights and narrow polydispersity indices (PDIs). In ε‐CL polymerization, the activity of complex 1 is greater than that of complex 2 , likely because of the greater Lewis acidity of Mg2+ metal caused by the electron‐withdrawing substitute trifluoromethyl (? CF3) at the 4‐position of the benzenesulfonate group. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3564–3572, 2010  相似文献   
994.
With adjustable pulse durations, a semiconductor saturable absorber mirror (SESAM) passively mode-locked picosecond Nd:YVO4 laser was studied. The pulse duration was adjustable from 20 to 80 ps by using intracavity etalons of different thicknesses.  相似文献   
995.
996.
The Gisin-Hughston-Jozsa-Wootters theorem plays an important role in analyzing various theories about quantum information, quantum communication, and quantum cryptography. It means that any purifications on the extended system which yield indistinguishable state ensembles on their subsystem should have a specific local unitary relation. In this Letter, we show that the local relation is also established even when the indistinguishability of state ensembles is extended to that of operator ensembles.  相似文献   
997.
998.
陈永洲  付春花  常慧  李南  何大韧 《中国物理 B》2008,17(10):3580-3587
In this paper, an empirical investigation is presented, which focuses on unveiling the universality of connectivity correlations in three spaces (the route space, the stop geographical space and bus-transferring space) of urban bustransport networks (BTNs) in four major cities of China. The underlying features of the connectivity correlations are shown in two statistical ways. One is the correlation between the (weighted) average degree of all the nearest neighbouring vertices with degree k, (Knn^w,(k)) Knn(k), and k, and the other is the correlations between the assortativity coefficient r and, respectively, the network size N, the network diameter D, the averaged clustering coefficient C, and the averaged distance (l). The obtained results show qualitatively the same connectivity correlations of all the considered cities under all the three spaces.  相似文献   
999.
The three-dimensional (3D) problem of the ground vibration isolation by an in-filled trench as a passive barrier is studied theoretically. Integral equations governing Rayleigh wave scattering are derived based on the Green’s solution of Lamb problem. The integral equations are solved accurately and efficiently with an iteration technique. They are used to evaluate the complicated Rayleigh wave field generated by irregular scatterers embedded in an elastic half-space solid. The passive isolation effectiveness of ground vibration by the in-filled trench for screening Rayleigh wave is further studied in detail. Effects of relevant parameters on the effectiveness of vibration isolation are investigated and presented. The results show that a trench filled with stiff backfill material gets a better isolation effect than a soft one, and increasing the depth or width of the in-filled trench also improves its screening effectiveness. The effectiveness and the area of the screened zone are surging with the increase in the length of the in-filled trench. Supported by the National Natural Science Foundation of China (Grant Nos. 50678128 and 50538010) and the Research Fund for PhD Student of Chinese College (Grant No. 20050247030)  相似文献   
1000.
We introduce the similarity index (SI) for the classification of the sea floor from acoustic profiling data. The essential part of our approach is the singular value decomposition of the data to extract a signal coherent trace-to-trace using the Karhunen-Loeve transform. SI is defined as the percentage of the energy of the coherent part contained in the bottom return signals. Important aspects of SI are that it is easily computed and that it represents the textural roughness of the sea floor as a function of grain size, hardness, and a degree of sediment sorting. In a real data example, we classified a section of the sea floor off Cheju Island south of the Korean Peninsula and compared the result with the sedimentology defined from direct sediment sampling and side scan sonar records. The comparison shows that SI can efficiently discriminate the bottom properties by delineating sediment-type boundaries and transition zones in more detail. Therefore, we propose that SI is an effective parameter for geoacoustic modeling.  相似文献   
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