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1.
在双折射光纤中,根据受激拉曼散射和参量放大共同作用下的斯托克斯波和反斯托克斯波所满足的耦合模方程,考虑输入泵浦波是线偏振光,推导出了与泵浦波偏振方向垂直的的斯托克斯波和反斯托克斯波的增益系数;研究了双折射色散缓变光纤中,斯托克斯波和反斯托克斯波增益随相关参量的变化关系。结果表明,与泵浦波偏振方向垂直的斯托克斯波和反斯托克斯波增益的变化趋势是完全相同和对称的;同时表明,通过改变失配系数 ,在适当的传输位置,可以实现对斯托克斯波和反斯托克斯波有选择性的输出,以达到输出频率转换的目的。  相似文献   
2.
In this paper,we study the strong law of large numbers and Shannon-McMillan (S-M) theorem for Markov chains indexed by an infinite tree with uniformly bounded degree.The results generalize the analogous results on a homogeneous tree.  相似文献   
3.
This paper proposes a minimum contrast methodology to estimate the drift parameter for the Ornstein-Uhlenbeck process driven by fractional Brownian motion of Hurst index, which is greater than one half. Both the strong consistency and the asymptotic normality of this minimum contrast estimator are studied based on the Laplace transform. The numerical simulation results confirm the theoretical analysis and show that the minimum contrast technique is effective and efficient.  相似文献   
4.
本文研究了取值于可列状态空间的Cayley 树指标Markov 链状态与状态序偶发生频率的强大数定理, 所得结果推广了有限状态情形下相应的结果.  相似文献   
5.
Circadian rhythm is an important biological signal that regulates many behavior, physiology or cellular processes. This work find light noise can apparently influence the rhythm regularity but the rhythm period is relatively stable to it. The noise can play a constructive role to minimize its destructive effect on the rhythm regularity. There is always a worst noise intensity that the regularity is the most dramatically destroyed, however, even stronger noise can counterintuitively minimize this destructive effect.  相似文献   
6.
Accurate studies on dissociation energies of diatomic molecules   总被引:1,自引:0,他引:1  
The molecular dissociation energies of some electronic states of hydride and N2 molecules were studied using a parameter-free analytical formula suggested in this study and the algebraic method (AM) proposed recently. The results show that the accurate AM dissociation energies DeAM agree excellently with experimental dissociation energies Deexpt, and that the dissociation energy of an electronic state such as the 23△g state of 7Li2 whose experimental value is not available can be predicted using the new formula.  相似文献   
7.
本文在分析了双原子分子振动能级的完备性和有限性及其对统计计算带来的影响的基础上,借助代数(AM)方法得到的双原子分子振动能级完全集合,采用量子力学统计系综方法,讨论了双原子分子振动能量对宏观热力学性质的统计贡献,并以氮气为例计算了相应的热力学函数和振动热容量.结果表明,真实的双原子分子振动能级是有限的;确定最高振动量子数和振动能级完全集合是正确进行统计分析的基础和关键;考虑振动能级的完备性和有限性后,只能导致数值解而不是解析解,所得的结果优于谐振子模型的解析结果,与实验数据吻合得很好.  相似文献   
8.
本文通过在8-羟基喹啉的5位上引入氨基和取代的苯基,合成了系列二-[2-苯基吡啶(C^N)][5-取代-8-羟基喹啉(N^O)]铱(Ⅲ)配合物((C^N)2IrQ).这里CN代表2-苯基吡啶,Q代表5-取代-8-羟基喹啉.通过1HNMR、13CNMR、MS、元素分析、单晶X-衍射等对配合物的化学和晶体结构进行了表征.利用循环伏安、UV-Vis、光致和电致发光光谱等对它们的光物理性质进行了表征.热重分析表明苯环上的取代基对配合物热稳定性有很大影响.常温下,几种5-取代苯基喹啉铱配合物的溶液和固体产生红色磷光发射,光致发光(PL)光谱在666和687nm附近出现两个强度基本相等的发射峰.配合物的发光性质主要受喹啉环和5位苯基的影响,苯环上的取代基团对配合物的发光性质影响不大.而5-氨基喹啉铱配合物PL光谱的最大发射峰在550nm,其PL光谱主要受2-苯基吡啶的影响.将配合物二-[2-苯基吡啶(C^N)][5-(4-甲氧基苯基)-8-羟基喹啉(N^O)]铱(Ⅲ)(7b)掺杂在聚2,7-(9,9-二辛基)芴(PFO)和30%(质量分数)的2-对叔丁基苯基-5-对联苯基-1,3,4-口恶二唑(PBD)的主体材料中,制备了聚合物发光器件(OLED),器件电致发光(EL)光谱的发射峰在672nm处,18V时最大亮度为350cd/m2,在电压14V时CIE色坐标值为(0.61,0.33),是一红光OLED器件.  相似文献   
9.
A novel red-emitting binuclear platinum complex (dfppy)2Pt2(C8OXT)2 was synthesized and characterized,in which dfppy represents 2-(4’,6’-difluorophenyl)pyridinato unit and C8OXT is abbreviated for 5-(4-octyloxyphenyl)-1,3,4-oxadiazole-2-thiol as a bridging ancillary ligand.Its photophysical,electrochemical and electroluminescent characteristics were primarily studied.The made single-emissive-layer (SEL) polymer light-emitting devices using (dfppy)2Pt2(C8OXT)2 as emitter exhibited a saturated red emission peaked at 620nm.The best device performances were obtained in the device at 8wt% dopant concentration,with a maximum external quantum efficiency of 8.4%,a current efficiency of 4.2cd/A and brightness of 3228cd/m2.This work provides an effective approach to obtain high-efficiency red emission through construction of new binuclear platinum complex and its doped SEL devices.  相似文献   
10.
许维国  吕兴梅     张庆国     桂劲松  杨家振 《中国化学》2006,24(3):331-335
An ionic liquid (IL) BMIGaCh was prepared by directly mixing GaCl3 and 1-methyl-3-butylimidazolium chloride with molar ratio of 1/1 under argon atmosphere. The densities and surface tensions of this pure ionic liquid were determined in the temperature range of 268.15 to (338.15±0.1) K. A new theoretical model of ionic liquids, an interstice model, was applied to calculate the thermal expansion coefficient of IL BMIGaCh, a, and the magnitude order of its value calculated by the theory was the same as experimental one. Both Raman scattering and ab initio calculations indicate that GaCl4^- is the only species containing Ga in the ionic liquid BMIGaCl4.  相似文献   
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