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1.
The competition between the stimulated resonance Raman scattering(SRRS) of Rhodamine B(RhB) and the stimulated Raman scattering(SRS) of ethanol(C2H5OH) is observed at the RhB in C2H5OH solution.For different concentrations of the solution,the peak wavelengths of the SRRS,the amplified spontaneous emission(ASE),the fluorescence and the absorption of RhB are different.The SRRS of RhB and the SRS of C2H5OH are simultaneously generated when the concentration of the solution is 10 5 mol/L and the energy of the excitation laser is 20.4 mJ.Otherwise,only either the SRRS of RhB or the SRS of C2H5OH is generated.The SRRS can be amplified by the ASE gain when the SRRS is near the peak of the ASE,and the peak wavelength of the SRRS coincides with the wavelength of the maximal intensity ASE.  相似文献   

2.
We study the entanglement between the internal(coin)and the external(position)degrees of freedom in the dynamic and the static deterministic aperiodic quantum walks(QWs).For the dynamic(static)aperiodic QWs,the coin depends on the time(position)and takes two coins C(α)and C(β)arranged in the two classes of generalized Fibonacci(GF)and the Thue–Morse(TM)sequences.We found that for the dynamic QWs,the entanglement of three kinds of the aperiodic QWs are close to the maximal value,which are all much larger than that of the homogeneous QWs.Further,the first class of GF(1st GF)QWs can achieve the maximum entangled state,which is similar to that of the dynamic disordered QWs.And the entanglement of 1st GF QWs is greater than that of the TM QWs,being followed closely by the entanglement of the second class of GF(2nd GF)QWs.For the static QWs,the entanglement of three kinds of the aperiodic QWs are also close to the maximal value and 1st GF QWs can achieve the maximum entangled state.The entanglement of the TM QWs is between1st GF QWs and 2nd GF QWs.However,the entanglement of the static disordered QWs is less than that of three kinds of the aperiodic QWs.This is different from those of the dynamic QWs.From these results,we can conclude that the dynamic and static 1st GF QWs can also be considered as maximal entanglement generators.  相似文献   

3.
The ρ(NH_2) infrared(IR) frequencies and the corresponding full width at half maximum(FWHM) values for(CH_3)_2 NH_2 Fe~Ⅲ M ~Ⅱ(HCOO)_6(DMFe M, M = Ni, Zn, Cu, Fe, and Mg) are analyzed at various temperatures by using the experimental data from the literature. For the analysis of the IR frequencies of the ρ(NH_2) mode which is associated with the structural phase transitions in those metal structures, the temperature dependence of the mode frequency is assumed as an order parameter and the IR frequencies are calculated by using the molecular field theory. Also, the temperature dependence of the IR frequencies and of the damping constant as calculated from the models of pseudospin(dynamic disorder of dimethylammonium(DMA~+) cations)–phonon coupling(PS) and of the energy fluctuation(EF), is fitted to the observed data for the wavenumber and FWHM of the ρ(NH_2) IR mode of the niccolites studied here. We find that the observed behavior of the IR frequencies and the FWHM of this mode can be described adequately by the models studied for the crystalline structures of interest. This method of calculating the frequencies(IR and Raman) and FWHM of modes which are responsible for the phase transitions can also be applied to some other metal organic frameworks.  相似文献   

4.
The influences of the shear coaxial injector parameters on the combustion performance and the heat load of a combustor are studied numerically and experimentally. The injector parameters, including the ratio of the oxidizer pressure drop to the combustor pressure (DP ), the velocity ratio of fuel to oxidizer (R V ), the thickness (WO ), and the recess (HO ) of the oxidizer injector post tip, the temperature of the hydrogen-rich gas (TH ) and the oxygen-rich gas (TO ), are integrated by the orthogonal experimental design method to investigate the performance of the shear coaxial injector. The gaseous hydrogen/oxygen at ambient temperature (GH2 /GO2 ), and the hot hydrogen-rich gas/oxygen-rich gas are used here. The length of the combustion (LC ), the average temperatures of the combustor wall (TW ), and the faceplate (TF ) are selected as the indicators. The tendencies of the influences of injector parameters on the combustion performance and the heat load of the combustor for the GH2 /GO2 case are similar to those in the hot propellants case. However, the combustion performance in the hot propellant case is better than that in the GH2/GO2 case, and the heat load of the combustor is also larger than that in the latter case.  相似文献   

5.
张伟  薛军帅  周晓伟  张月  刘子阳  张进成  郝跃 《中国物理 B》2012,21(7):77103-077103
An AlGaN/GaN superlattice grown on the top of a GaN buffer induces the broadening of the full width at half maximum of (102) and (002) X-ray diffraction rocking curves. With an increase in the Si-doped concentration in the GaN wells, the full width at half maximum of the (102) rocking curves decreases, while that of the (002) rocking curves increases. A significant increase of the full width at the half maximum of the (002) rocking curves when the doping concentration reaches 2.5 × 1019 cm-3 indicates the substantial increase of the inclined threading dislocation. High level doping in the AlGaN/GaN superlattice can greatly reduce the biaxial stress and optimize the surface roughness of the structures grown on the top of it.  相似文献   

6.
The effects of incomplets ionization of nitrogen in 4H-SiC have been investigated.Poisson‘s equation is numerically analysed by considering the effects of Poole-Frenkel,and the effects of the potential on Nd^ (the concentration of ionized onors)and n(the concentration of electrons).The pinch-off voltages of the uniform and the ion-implanted channels of 4H-SiC metal-Semiconductor field-effect transistors(MESFETs) and the capacitance of the gate are given at different temperatures.Both the Poole-Frenkel effect and the potential have influence on the pinch-off voltage Vp of 4H-SiC MESFETs.Although the C-V characteristics of the ion-implanted and the uniform channel of 4H-SiC MESFETs have a clear distinction,the effects of incomplete ionization on the C-V characteristics are not shgnificant.  相似文献   

7.
Circulation system complex networks and teleconnections   总被引:1,自引:0,他引:1       下载免费PDF全文
龚志强  王晓娟  支蓉  冯爱霞 《中国物理 B》2011,20(7):79201-079201
In terms of the characteristic topology parameters of climate complex networks,the spatial connection structural complexity of the circulation system and the influence of four teleconnection patterns are quantitatively described.Results of node degrees for the Northern Hemisphere (NH) mid-high latitude (30°N-90°N) circulation system (NHS) networks with and without the Arctic Oscillations (AO),the North Atlantic Oscillations (NAO) and the Pacific-North American pattern (PNA) demonstrate that the teleconnections greatly shorten the mean shortest path length of the networks,thus being advantageous to the rapid transfer of local fluctuation information over the network and to the stability of the NHS.The impact of the AO on the NHS connection structure is most important and the impact of the NAO is the next important.The PNA is a relatively independent teleconnection,and its role in the NHS is mainly manifested in the connection between the NHS and the tropical circulation system (TRS).As to the Southern Hemisphere mid-high latitude (30°S-90°S) circulation system (SHS),the impact of the Antarctic Arctic Oscillations (AAO) on the structural stability of the system is most important.In addition,there might be a stable correlation dipole (AACD) in the SHS,which also has important influence on the structure of the SHS networks.  相似文献   

8.
The transient properties of a three-level atomic optical bistable system in the presence of multiplicative and additive noises are investigated. The explicit expressions of the mean first-passage time (MFPT) of the transition from the high intracavity intensity state to the low one are obtained by numerical computations. The impacts of the intensities of the multiplicative noise D M and the additive noise D A , the intensity of correlation between two noises λ , and the intensity of the incident light y on the MFPT are discussed, respectively. Our results show: (i) for the case of no correlation between two noises (λ = 0.0), the increase in D M and D A can lead to an increase in the probability of the transition to the low intracavity intensity state, while the increase in y can lead to a retardation of the transition; and (ii) for the case of correlation between two noises (λ = 0.0), the increase in λ can cause an increase in the probability of the transition, and the increase in D A can cause a retardation of the transition firstly and then an increase in the probability of the transition, i.e., the noise-enhanced stability is observed for the case of correlation between two noises.  相似文献   

9.
Fourier transform infrared spectroscopy (FTIR) was employed to study the human epidermis larynx car- cinoma cell lines (Hep-2) which were irradiated by different doses of X-ray.The results show that (1) the irradiation of X-ray damages the structure of the CH_3 groups of the thymine in DNA,which restrains the reproduction of Hep-2 cells effectively,(2) the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins,lipids and the nucleic acid molecules intercellular in the greatest degree,and (3) the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently.Meanwhile,the apoptosis of these cells were detected by using flow cytometry (FCM) primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent,but is not linearly.And the apoptotic ratio of the 12 Gy dose group is the maximum (20.36%),but the apoptotic ratios of the 2 to 8 Gy dose groups change little.  相似文献   

10.
We have performed Monte Carlo simulations of the rotation of single stars and companions of compact objects(The compact objects are white dwarfs(WDs) and neutron stars(NSs)) in close binaries.We present a comparison between the rotation of companions of compact objects and that of single stars.We find that the rotation of the companions of compact objects is on average faster than that of the single stars.According to the distribution of the orbital period and the rotation angular velocity,we find that the rotation of the companions of compact objects is mostly accelerated by stable mass transfer.Tidal forces of the compact object can also affect the rotation of companion.  相似文献   

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