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1.
We derive the low energy effective action for the dilatonic braneworld. In the case of the single-brane model, we find the effective theory is described by the Einstein-scalar theory coupled to the dark radiation. Remarkably, the dark radiation is not conserved in general due to a coupling to the bulk scalar field. The effective action incorporating Kaluza-Klein (KK) corrections is obtained and the role of the AdS/CFT correspondence in the dilatonic braneworld is revealed. In particular, it is shown that CFT matter would not be confined to the braneworld in the presence of the bulk scalar field. The relation between our analysis and the geometrical projection method is also clarified. In the case of the two-brane model, the effective theory reduces to a scalar-tensor theory with a non-trivial coupling between the radion and the bulk scalar field.  相似文献   

2.
We report a three parameter family of solutions for dilaton gravity in 2+1 dimensions with finite mass and finite angular momentum. These solutions are obtained by a compactification of vacuum solutions in 3+1 dimensions with cylindrical symmetry. One class of solutions corresponds to conical singularities and the other leads to curvature singularities.  相似文献   

3.
Neutrino oscillation and CP violation effects are discussed in an SUSY model proposed in Ref. [1]. The oscillation probabilities expected by this model in short baseline and long baseline neutrino oscillation experiments are calculated.  相似文献   

4.
采用分幅扫描单光子计数荧光光谱装置,研究温度升高对PSⅡ CP47/D1/D2/Cyt b559复合物能量传递的影响.获得分别在20℃、42℃和48℃处理后,CP47/D1/D2/Cyt b559复合物主发射峰所在的波长未发生多大改变,均在682 nm,但其荧光强度逐渐降低,而大约730 nm处主发射峰的振动副带发生了明显的变化,42℃其弱峰趋势已不显著,相对荧光强度下降,48℃弱峰趋势已完全消失;最大峰值处获得两个时间组分,这两个组分都属于电荷重组.其中,1~2 ns组分随处理温度的升高变化不大,而7~20 ns组分随温度升高变化较大,并且逐渐延长.因此,处理温度的升高使CP47/D1/D2/Cyt b559复合物的二级结构、色素分布的空间位置发生变化,从而影响了CP47/D1/D2/Cyt b559复合物中的能量传递以及电荷重组.42℃已对其造成影响,而48℃对其影响很大.  相似文献   

5.
We revisit the novel symmetries in ${ mathcal N }=2$ supersymmetric quantum mechanical models by considering specific examples of coupled systems. Further, we extend our analysis to a general case and list out all the novel symmetries. In each case, we show the existence of two sets of discrete symmetries that correspond to the Hodge duality operator of differential geometry. Thus, we are able to provide a proof of the conjecture which points out the existence of more than one set of discrete symmetry transformations corresponding to the Hodge duality operator. Moreover, we derive on-shell nilpotent symmetries for a generalized superpotential within the framework of supervariable approach.  相似文献   

6.
本文主要研究了基于SnO2/CuO薄膜的声表面波(SAW)传感器(室温下,工作频率约为147.8 MHz)检测H2S气体的特性。以36°YXLiTaO3为基片制作声表面波器件,通过采用射频磁控溅射法在其表面淀积SnO2/CuO的复合薄膜制作出H2S气体传感器。由场发射电子扫描电镜观察薄膜,薄膜连续均匀且表面分布大量微气孔,因而具有良好的吸附性。然后本文在85℃~205℃范围内对传感器的吸附和脱附速率、灵敏度及选择性等进行了实验研究。实验结果表明,所制备的传感器在较低温度下同时具备快速吸附和脱附特性,工作在190℃时气体吸附和脱附速率最快,检测20ppm H2S的响应和恢复时间分别为30s、15s;工作在160℃时,传感器检测20ppmH2S的灵敏度最高,工作频率变化约230 kHz,且对于低浓度2 ppm H2S,频率变化可达45 kHz。同时,传感器也表现出良好的重复性和选择性。  相似文献   

7.
The time evolution of the Hamming distance (damage spreading) for the S=1/2 and S=1 Ising models on the square lattice is performed with a special metropolis dynamics algorithm. Two distinct regimes are observed according to the temperature range for both models: a low-temperature one where the distance in the long-time limit is finite and seems not to depend on the initial distance and the system size; a high-temperature one where the distance vanishes in the long-time limit. Using the finite size scaling method, the dynamical phase transition (damage spreading transition) temperature is obtained as Tc≌1.675±0.025 for the S=1 Ising model.  相似文献   

8.
9.
The purpose of the current study was to determine how maximum phonationduration (MPD) of five notes (C4, D4, E4, F4, 134) sustained on /o/, sustained vowels (/i/, //, /a/, /u/), and s/z ratio (sustained /s/ and /z/ changed during voice therapy for vocal nodules. Voices of adult females before treatment and after resolution of vocal nodules were analyzed via the PM Pitch Analyzer. Treatment included tension reduction, abuse identification and elimination, laryngeal strengthening, and home exercises. Results indicate there was no significant difference in maximum phonation duration or S/Z ratio before and after treatment. Results revealed that females with vocal nodules demonstrate measurements before therapy similar to measures considered to be normal in persons without vocal nodules. Application of findings to clinical practice is discussed.  相似文献   

10.
Our previous study suggested new sonodynamic therapy for cancer cells based on the delivery of titanium dioxide (TiO2) nanoparticles (NPs) modified with a protein specifically recognizing target cells and subsequent generation of hydroxyl radicals from TiO2 NPs activated by external ultrasound irradiation (called TiO2/US treatment). The present study first examined the uptake behavior of TiO2 NPs modified with pre-S1/S2 (model protein-recognizing hepatocytes) by HepG2 cells for 24 h. It took 6 h for sufficient uptake of the TiO2 NPs by the cells. Next, the effect of the TiO2/US treatment on HepG2 cell growth was examined for 96 h after the 1 MHz ultrasound was irradiated (0.1 W/cm2, 30 s) to the cells which incorporated the TiO2 NPs. Apoptosis was observed at 6 h after the TiO2/US treatment. Although no apparent cell-injury was observed until 24 h after the treatment, the viable cell concentration had deteriorated to 46% of the control at 96 h. Finally, the TiO2/US treatment was applied to a mouse xenograft model. The pre-S1/S2-immobilized TiO2 (0.1 mg) was directly injected into tumors, followed by 1 MHz ultrasound irradiation at 1.0 W/cm2 for 60 s. As a result of the treatment repeated five times within 13 days, tumor growth could be hampered up to 28 days compared with the control conditions.  相似文献   

11.
In this paper, we introduce the reduced matrix in kq representation and provide the reduced matrix elements of a projection operator \hat{P} on the rational noncommutative orbifold T2/Z4. we give the closed form for the projector by Jacobi elliptical functions. Since projectors correspond to soliton solutions of the field theory on the noncommutative orbifold, we thus present a corresponding soliton solution.  相似文献   

12.
应用密度泛函理论的B3LYP方法和6-311++g(d,p)基组,研究Li2、LiS和Li2S分子的基态构型.结果表明它们的基电子态分别为X1Σg+、X2Π和X1Σg+.通过非线性曲线拟合,得到基态LiS和Li2分子的4参数Murrell-Sorbie分析势能函数,计算它们的光谱参数和力常数.基于多体项展式理论得到了基态Li2S分子的单重态势能面的分析函数.利用得到的分析势能函数重构基态单重Li2S分子的旋转图、伸缩图和旋转伸缩图,准确地再现了Li2S分子的静态特征,如平衡结构,最低能量,合理反应通道.从等值势能面图看出,反应Li+S+Li→Li2S是一个无阈值反应.S原子攻击Li2分子的反应通道上,有一个过渡态.Li原子攻击LiS分子通道上也有一个过渡态.  相似文献   

13.
TEXONO合作组首次采用CsI(T1)晶体测量反应堆中微子的能量、通量和反常磁矩,描述了实验的基本原理,探测器结构及其性能.  相似文献   

14.
The singular manifold method is used to obtain two general solutions to a (2 1)-dimensional breaking soliton equation, each of which contains two arbitrary functions. Then the new periodic wave solutions in terms of the Jacobi elliptic functions are generated from the general solutions. The long wave limit yields the new types of dromion and solitary structures.  相似文献   

15.
The static kinks and their low energy excited states in scalar field theories with V[φ]= -(1/2)m2φ2 + gφ2n/2n are studied in a function-series method. We give a universal formal solution, and a universal approach to find the low energy excited states as well. Excellent agreement between the FS solution and the exact answer is found. This confirms our predicted results of the energies of the excited quantum states by considering small oscillations about the kink motion.  相似文献   

16.
研发了一种基于Internet的远程电脑测配色系统。它能够实现远程测色和配色,具有多种配色模型,能够对来自不同行业的光谱数据以及光谱图像进行处理和分析。介绍了配色系统的部分设计。采用B/S和C/S相结合的构架实现了配色用户和配色服务商在互联网上的远程互动。介绍了有关的配色算法和远程配色系统的搭建过程以及相关程序编写方案。  相似文献   

17.
With the strong-field scheme and trigonal bases, the complete d3 energy matrix in a trigonally distorted cubic-field has been constructed. By diagonalizing this matrix, the normal-pressure energy spectra and wavefunctions of GSGG:Cr3+ at 70 K and 300 K have been calculated without the electron-phonon interaction (EPI), respectively. Further, the contributions to energy spectra from EPI at two temperatures have also been calculated, where temperatureindependent terms of EPI are found to be dominant. The sum of aforementioned two parts gives rise to the total energy spectrum. The calculated results are in good agreement with all the optical-spectral experimental data and the experimental results of g||(R1) and g⊥(R1). It is found that the contribution from EPI to R1 line of GSGG:Cr3+ with taking into account spin-orbit interaction (Hso) and trigonal field (Vtrig) is much larger than the one with neglecting Hso and Vtrig, and accordingly it is essential for the calculation of the EPI effect to take first into account Hso and Vtrig. The admixture of base-wavefunctions, |t32 2E) and |t22(3T1)e4T2 ), the average energy separation △= E[t22 (3T1)e4T2]-E[t32 2E] and their variations with temperature have been calculated and discussed.  相似文献   

18.
利用代数方法研究了非对称弯曲三原子分子S2O分子处于C1A'电子态的能谱及其稳定构型下的势能面,通过对30条光谱数据的拟和得到的rms误差为2.40 cm-1.结果表明,利用此代数Hamiltonian很好的实现了能级再现,它预测了振动总量子数达到20的全部振动能级,同时我们计算了分子的解离能与力常数.通过与实验值比较证明了这种方法在计算这类分子的有效性.  相似文献   

19.
Bi2S3纳米复合材料的非线性光学性质   总被引:2,自引:1,他引:2  
利用单光束 Z扫描技术 ,在波长为 1 .0 64μm、脉宽为 38ps条件下测定了不同热处理条件下表面包覆纳米 Bi2 S3 掺杂有机改性硅酸盐材料的三阶光学非线性。结果发现室温下自然干燥的样品和在 N2 气氛下 1 50℃加热处理 2小时后的样品的三阶光学非线性极化系数分别为5.8× 1 0 -1 3 esu和 3.7× 1 0 -1 2 esu。后者的三阶光学非线性极化系数比前者几乎大一个数量级。显然 ,适当的热处理能增强样品的三阶光学非线性。对此现象进行了分析和讨论。  相似文献   

20.
New exact solutions in terms of the Jacobi elliptic functions are obtained to the (2+1)-dimensional breaking soliton equation by means of the modified mapping method. Limit cases are studied, and new solitary wave solutions and triangular periodic wave solutions are obtained.  相似文献   

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