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排序方式: 共有130条查询结果,搜索用时 250 毫秒
1.
Wang  Rong  Li  Xu  Zhou  Youshi  Cao  Shuxuan  Xu  Honghao  Han  Wenjuan  Zhang  Yuxia  Liu  Junhai 《Journal of Russian Laser Research》2022,43(4):476-481
Journal of Russian Laser Research - We demonstrate a passively-mode-locked Pr3+: LuLiF4 laser operated at the 604 nm orange wave-length, using monolayer graphene as a saturable absorber. The...  相似文献   
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Based on the actual competition in the Chinese property insurance market, the repeated price game model for four oligarchs with different decision rules is built. On the basis of analyzing the stabilities of eight fixed points about the four-dimensional dynamic system, the Nash equilibrium and its local stable region are discussed mainly. Then the complexity of the four-dimensional discrete dynamic system and its evolutionary process are studied. Finally, the delay feedback control method is used to control the chaos. Numerical simulation results have shown that the influence which the change of price adjustment speed has on the movement of dynamic system has a sensitive dependence on the initial conditions, and there is a strong connection between the profit of each oligarch and the price adjustment speed or the control parameters, and the corresponding economic explanation to those phenomena will have important reference values to the realistic problems.  相似文献   
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分析了(銫) (Cs)原子作为旋光介质的线性法拉第磁光效应.采用二能级模型解释了(銫)原子与光的相互作用,并利用琼斯矩阵推导了当激光器的频率处于(銫)原子共振线时,经过(銫)气室的线偏振光的旋转角与外加磁场的关系式,利用此关系式可测量磁场强度的大小和气室内(銫)原子的浓度.实验采用852nm分布反馈半导体激光器作为光源...  相似文献   
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Based on the researches of Szydlowski and Krawiec, we studied the inherent complexity of a chaotic business cycle with great excitements in non-resonant condition. First, we got the first-order and second-order approximate solutions of the system by using multiple scale method. Then deduced the formulation reflecting the complex relations between vibration, phase, bifurcation parameter μ and excite frequency Ω of first-order solution. As the great excitement F varied, the global changes of the system solutions were analyzed. We also explored the different paths leading the systems with different parameter combinations into catastrophe region, fuzzy region or chaos region. Finally, we discussed the evolution trends of business cycle models under the above-mentioned conditions. Hence, this paper has some theoretical and practical significance.  相似文献   
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A series of tri-substituted chiral pyrrolidin-2-one derivatives have been designed and synthesized as CC chemokine receptor 4 (CCR4) antagonists. The structure of CCR4 was built by homology modeling. Asymmetric synthesis was applied to synthesize the R,R configuration chiral pyrrolidin-2-one scaffold. The stereoisomeric con- figurations of the compounds were identified by 2D I H-~H COSY spectroscopy and 1D NOESY spectroscopy. This method was more economical and convenient than traditional X-ray single crystal diffraction. In addition, the inter- actions between these compounds and the N-terminal extracellular tail of CCR4 were studied using capillary zone electrophoresis. The CCR4 chemotaxis inhibition effect was tested in CCR4-transfected HEK293 cells. Several compounds showed potent activities as CCR4 antagonists. Among these compounds, lc is the most active one. Its apparent binding constant of CZE experiment result is (1.569±0.11)× 10s L·mol ^-1, and its percentage inhibition of the HEK293/CCR4 cells migration with the concentration of I gmol·L ^-1 in DMSO is 59%. And compound If has slightly higher affinity to N-terminal of CCR4 according to its apparent binding constant than lb because of the in- troduced ester linkage. Further studies on the mechanism of these compounds are in progress.  相似文献   
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Liu J  Tian X  Zhou Z  Wu K  Han W  Zhang H 《Optics letters》2012,37(12):2388-2390
Efficient laser operation is demonstrated at room temperature with a new Yb:Lu3Ga5O12 garnet crystal. A continuous-wave output power of 5.36 W is generated at a center oscillation wavelength of 1041 nm, with an optical-to-optical efficiency of 51% and the slope efficiency of 63%. In passively Q-switched operation, the maximum average output power reaches 4.0 W (center wavelength of 1034 nm) at a repetition rate of 71 kHz, with optical-to-optical and slope efficiencies measured to be 40% and 50%, respectively. Laser pulses of 26 ns duration are generated with a pulse energy of 91 μJ and peak power of 3.5 kW.  相似文献   
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用于全光铯原子磁力仪的激光器稳频技术研究   总被引:1,自引:0,他引:1  
全光铯原子磁力仪是采用光学的方法实现微弱磁场检测,激光频率稳定性直接影响磁力仪的灵敏度。分析了二向色性原子蒸气激光频率锁定(Dichroic atomic vapor laser lock DAVLL)技术用于稳定激光器频率的原理,及其在全光原子磁力仪中的应用优势,发现通常的二能级原子模型不适用于分析铯原子D2线的稳频。实验测量了不同磁场下铯原子D2线基态Fg=4和Fg=3跃迁的DAVLL光谱,发现16mT是实现DAVLL稳频的最佳磁场;在此磁场附近,基态Fg=4跃迁鉴频曲线零点相对于Fg=4→Fe=5跃迁会产生6MHz/mT的线性频移,基态Fg=3跃迁鉴频曲线零点相对于Fg=3→Fe=4线会产生-9MHz/mT的线性频移。  相似文献   
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1 Introduction  Self frequency doublinglasercrystals,whichcombinetwodifferentfunctionsoflaseremissionandfrequencyconversion ,provideasimplewayofgeneratingcoherentvisibleradiation .Amongthevariousself frequency doublingcrystals ,neodymiumyttriumaluminumbora…  相似文献   
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