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941.
942.
We evaluate the non-Markovian effects on the entanglement dynamics of a fermionic system interacting with two dissipative vacuum reservoirs. The exact solution of density matrix is derived by utilizing the Feynman–Vernon influence functional theory in the fermionic coherent state representation and the Grassmann calculus, which are valid for both the fermionic and bosonic baths, and their difference lies in the dependence of the parity of the initial states. The fermionic entanglement dynamics is presented by adding an additional restriction to the density matrix known as the superselection rules. Our analysis shows that the usual decoherence suppression schemes implemented in qubits systems can also be achieved for systems of identical fermions, and the initial state proves its importance in the evolution of fermionic entanglement. Our results provide a potential way to decoherence controlling of identical fermions. 相似文献
943.
In this paper, we consider quantitative stability analysis for two-stage stochastic linear programs when recourse costs, the technology matrix, the recourse matrix and the right-hand side vector are all random. For this purpose, we first investigate continuity properties of parametric linear programs. After deriving an explicit expression for the upper bound of its feasible solutions, we establish locally Lipschitz continuity of the feasible solution sets of parametric linear programs. These results are then applied to prove continuity of the generalized objective function derived from the full random second-stage recourse problem, from which we derive new forms of quantitative stability results of the optimal value function and the optimal solution set with respect to the Fortet–Mourier probability metric. The obtained results are finally applied to establish asymptotic behavior of an empirical approximation algorithm for full random two-stage stochastic programs. 相似文献
944.
Black phosphorus saturable absorber for ultrafast mode‐locked pulse laser via evanescent field interaction
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Kichul Park Junsu Lee Young Tack Lee Won‐Kook Choi Ju Han Lee Yong‐Won Song 《Annalen der Physik》2015,527(11-12):770-776
Black phosphorus, or BP, has found a lot of applications in recent years including photonics. The most recent studies have shown that the material has an excellent optical nonlinearity useful in many areas, one of which is in saturable absorption for passive mode‐locking. A direct interaction scheme for mode‐locking, however, has a potential to optically cause permanent damage to the already delicate material. Evanescent field interaction scheme has already been proven to be a useful method to prevent such danger for other 2‐dimensional nanomaterials. In this report, we have utilized the evanescent field interaction to demonstrate that the optical nonlinear characteristics of BP is sufficiently strong to use in such an indirect interaction method. The successful demonstration of the passive mode‐locking operation has generated pulses with the pulse duration, repetition rate, and time bandwidth product of 2.18 ps, 15.59 MHz, and 0.336, respectively. 相似文献
945.
Ping Yin Yucai Hu Chunhua Wang Yuan Tian Qinghua Tang Chongrong Bao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):514-522
Theoretical studies on the thermodynamic and kinetic properties of the reactions of Ti+ with sulfur transfer reagent SCO via the C═S bond activation pathway have been carried on using DFT/B3LYP method, general statistical thermodynamics, and Eyring transition state theory with Wigner correction. The relevant reactions include reaction 1 4 Ti++1SCO → 4 IM 1 → 4 TS 1 → 4 IM 2 → 4 TiS++ 1 CO, and reaction 2 4Ti++1SCO →4IM1→ CP →2IM2→2TiS++1CO in which the spin multiplicity changes from the quartet state to the doublet state in the crossing region. It is concluded that the increase of the temperature is favored to the reaction 1 process, since the equilibrium constants (K) rises from 0.566 × 10[P]-9 at 200 K to 0.109 × 100 at 1200 K, and the reaction rate constant (k) from 0.222 × 100 s[P]-1 at 200 K to 0.540 × 10 11 s[P]-1 at 1200 K. Moreover, reaction 1 is endothermic, and non-spontaneous in the way the entropy increases, while reaction 2 is exothermic and spontaneous in the way their entropy decreases. The reaction path 2 is the energetically favorable channel, and its thermodynamic data change not largely with the rise of temperature. 相似文献
946.
Han Joong Koh Suk Jin Kang Dennis N. Kevill 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1404-1415
Kinetic and product studies of the solvolyses of acyclic phosphorochloridates are extended to two cyclic diesters, 2-chloro-1,3,2-dioxaphospholane-2-oxide (1) and 2-chloro-5,5-dimethyl-1,3,2-dioxaphosphorinane-2-oxide (2). Slightly faster solvolyses are observed for 1 than for the acyclic dimethyl phosphorochloridate (3), and 2 solvolyzes somewhat slower than 3. An extended Grunwald–Winstein equation treatment shows similar sensitivities to changes in solvent nucleophilicity and solvent ionizing power for 1, 2, and 3, and a concerted SN2 attack is proposed in each case. Product studies for the solvolyses of 2 in aqueous alcohols are presented. 相似文献
947.
948.
949.
Sevil Şenkardeş İhsan Han Hakan Hançer Mürüvvet Abbak Özge Çevik Ş. Güniz Küçükgüzel 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1164-1170
AbstractA series of thiosemicarbazides were synthesized and structurally characterized by spectroscopic techniques (NMR, FT-IR) besides elemental analysis. These compounds were evaluated for their cytotoxicity against human breast cancer cell line MCF7 and prostate cancer cell line PC3 and nonmalignant fibroblast L929 cell line by MTT assay. Among the compounds, N-[2-(4-chlorophenyl)ethyl]-2-[(4-methylphenyl)sulfonyl]hydrazinecarbothioamide (3d) and 2-[(4-methylphenyl)sulfonyl]-N-[4-(trifluoromethoxy)phenyl]hydrazinecarbothioamide (3f) were found to display significant cytotoxicity with IC50 of 13.87?μM (against PC3 cell line) and 1.47?μM (against MCF7 cell line), respectively. These compounds were non-cytotoxic to normal cell line with IC50>100?μM. Western blotting studies demonstrated that compound 3f induced apoptosis and caused cell death in the MCF7 and PC3 cell lines via an increase in Bax protein expression and a slight decrease in Bcl-2 protein expression. The gene expression ratio Bax/Bcl-2 showed the induction of mitochondrial apoptosis in cancer cell lines. All of synthesized compounds have also been tested for antioxidant activity and all compounds achieved strong inhibition of the DPPH radical. These findings showed that compound 3f, displays potential to be further explored in the development of new anticancer agents. 相似文献
950.
Jiang-Sheng Han Yin-Lin Shao Xiao-Hong Zhang Ping Zhong 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1599-1610
Abstract An efficient and green aqueous protocol to access 3-chalcogen benzo[b]furan derivatives has been developed. The reaction can proceed via I2-mediated intramolecular annulation reaction of 2-alkynylanisoles with diaryl disulfides (diselenides) in water or under solvent-free conditions at room temperature. With the participation of I2, a variety of 3-chalcogen benzo[b]furan derivatives were obtained in good to excellent yields. This reaction was considered to work via an iodocyclization cascade mechanism and the intermediate 3-iodo-2-phenylbenzofuran was detected by GC-MS. 相似文献