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排序方式: 共有48条查询结果,搜索用时 15 毫秒
1.
Dong  Liangwei  Qi  Wei  Peng  Ping  Wang  Linxue  Zhou  Hui  Huang  Changming 《Nonlinear dynamics》2020,102(1):303-310
Nonlinear Dynamics - We address the nonlinear dynamics of binary Bose-Einstein condensates with mutually symmetric spinor components trapped in an optical lattice. The interaction between the...  相似文献   
2.
Zeng  Liangwei  Belić  Milivoj R.  Mihalache  Dumitru  Shi  Jincheng  Li  Jiawei  Li  Siqi  Lu  Xiaowei  Cai  Yi  Li  Jingzhen 《Nonlinear dynamics》2022,108(2):1671-1680
Nonlinear Dynamics - We demonstrate the existence of various types of gap localized modes, including one- and two-dimensional (1D and 2D) single solitons and soliton clusters, as well as the...  相似文献   
3.
1NTRODUCTIONTheacrylateterpolymer--supPOrtedsulfideplatinumcomplexanddisulfideplatinumcomplex['--2]werestudiedinthehydrosilylationofolefins.Itisfoundthattheyhavehighcatalyticactivityandreusedproperties.LiuXFetal.[3)synthesizedselena--crowneitherplatinumcomplexesandreportedtheircatalyticactivityofhydrosilylation.Clarketal.[4)reportedthatthecatalyticactivityofPiLL'Clz(L=PPh2,L'=S,N)ishigherthanthatofPtLZC12orPtL'ZC12inhydrosilylation.Inthispaper,wereportthesynthesisofanewacrylatete…  相似文献   
4.
利用光折变晶体的电光、压电效应实现2×2光开关的原理   总被引:7,自引:0,他引:7  
讨论了在光折变LiNbO3晶体中建立电场控制的 2× 2直通交换开关的原理设计方案。通过控制读出光栅时外加电场的大小使读出光满足或偏离布拉格条件 ,从而控制衍射效率为 1或 0 ,实现开关的交换和直通操作。全面考虑了电场作用下晶体的压电和电光效应 ,基于衍射效率公式和光栅的布拉格条件 ,给出了为获得最佳衍射效率比时外加电场及写入光束比与记录角度间的关系曲线  相似文献   
5.
In this paper,an equivalence relation between the ω-limit set of initial values and the ω-limit set of solutions is established for the Cauchy problem of evolution p-Laplacian equation in the unbounded space Yσ(RN).To overcome the difficulties caused by the nonlinearity of the equation and the unbounded solutions,we establish the propagation estimate and the growth estimate for the solutions.It will be demonstrated that the equivalence relation can be used to study the asymptotic behavior of solutions.  相似文献   
6.
The carboranylpyrrole polymers are functional materials with superior thermal resistance and conducting performances. The carboranylpyrrole structures and Laplacian bond order (LBO) of carborane moiety, as well as the thermal resistance and conducting properties of carboranylpyrrole dimers or polymers, were investigated theoretically. The 11B NMR chemical shifts of 3-(2-methyl-o-carboranyl)alkyl-1H-pyrrole monomers (CP-1 to CP-5) were calculated and analyzed. The average LBO values of some characteristic chemical bonds in the carborane cages of CP-1 to CP-5 molecules were calculated. It is found that the average LBO values of carborane moieties change slightly with the increase in alkyl chain length. The temperature resulting in about 15–20 % weight loss for CP-1, CP-3, CP-4 and CP-5 polymers is predicted to be more than 700 °C. Apart from the C–C bonds in carborane moieties of 3-(2-R-o-carboranyl)propyl-1H-pyrrole (R = CH2OH, CH2OCH3, CN, COCl, Ph) substituents, the LBO values of other bonds in these cages change slightly relative to that in the molecule of 3-(2-methyl-o-carboranyl)propyl-1H-pyrrole (CP-3). The C–C bond LBO values in the carborane cages of these substituents with electron-donating groups (R = CH2OH, CH2OCH3) are bigger than that in CP-3, while those values in those substituents with electron-withdrawing groups (R = CN, COCl, Ph) are smaller than that in CP-3. The polymerization activity calculated for CP-1 to CP-5 monomers increases with the increase in alkyl chain length. The calculated orbital energy gap (?E LUMO?HOMO) of CP-1 to CP-5 dimers decreases with the increase in alkyl chain length, and accordingly, the electronic conductivity has the potential to increase. In addition, the calculated band gaps of CP-1 to CP-5 dimers cell models also decrease with the increase in alkyl chain length.  相似文献   
7.
Cimetidine reacting with 1,5-dichloroanthraquinone in acetone solution can produce a charge-transfer complex that shows a strong absorption peak at 343 nm. The absorption value at 343 nm increased with cimetidine concentration in the range of 0.01—0.5 μg/mL, with regression coefficient of 0.9995 and detection limit of 0.006 μg/mL. This simple and sensitive method has been successfully applied to determine cimetidine in tablets and capsules, with average recovery of (98.47±0.92)% and (97.07±1.16)%, respectively. Furthermore, the mole ratio of the complex between cimetidine and 1,5-dichloroanthraquinone is 2∶1, and the mechanism of charge-transfer reaction is explored.  相似文献   
8.
In this paper, we present a novel method to detect license plates in video sequences automatically. The framework mainly integrates the cascade detectors method and the Tracking Learning Detection (TLD) algorithm. The cascade detectors are used to detect license plates, and the TLD algorithm is adopted to track the license plate regions. The license plates in the first frame image are detected by the cascade detectors to build the original tracking list, the tracking results and the detection results in following frames will be compared, and the newly appearing license plate information will be added to the tracking list. Meanwhile, the tracking results existing in the current tracking list would be replaced by the corresponding detection results with higher degree of confidence. We demonstrate the effectiveness of our algorithm for license plate detection task on a road intersection dataset, and the experimental evaluation shows the detection performance has been greatly improved by synthetically using the detection and tracking strategy.  相似文献   
9.
锗在国防工业、航空航天和通信等领域中的战略性,锗含量的测定对于保证材料质量和满足国际标准至关重要。本文综述了锗含量测定方法的多种技术,包括分光光度法、原子荧光光谱法、原子吸收光谱法、电感耦合等离子体原子发射光谱法、电感耦合等离子体质谱法以及滴定法。在每个检测方法的介绍中,详细探讨了方法的原理、前处理步骤以及应用范围,并分别总结了各个方法的优势和不足。最后,强调了锗含量测定方法的意义,特别是在满足出口监管和促进科学研究方面的作用。同时对锗元素的测定方法进行了展望,为未来的发展提供了参考方向。  相似文献   
10.
采用固相反应法制备了不同烧结温度(950~1180℃)、烧结时间、烧结次数共7种工艺的Sr3 YCo4 O10.5+δ多晶块材,通过热分析、XRD、SEM确定了有序化相变和最佳烧结工艺(1180℃/24 h+1180℃/24 h),并研究了多晶的电磁性能.结果表明,964℃完全晶化的四方相Sr3 YCo4 O10.5在...  相似文献   
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