排序方式: 共有115条查询结果,搜索用时 31 毫秒
61.
临界点附近的H2气体的状态方程 总被引:8,自引:2,他引:6
将Benedict-Webb-Rubin(BWR)方程应用于H2气体,采用非线性最小二乘法,精选参与拟合的实验数据和初始参数,拟合出了适用于温度30K-700K、压强0.1atm-100.00atm范围H2气体的有关参数,进而作了全部P-V-T回代计算,通过计算值与实验值的比较发现:H2气体温度在临界点附近(30K-40K),压强达100.00atm和密度超过临界密度ρc的两倍时,BWR方程仍能计 相似文献
62.
Theoretical Study of the Influence of Femtosecond Laser Wavelength on the Evolution of a Double-Minimum Electronic Excited State Wave Packet for NaRb 下载免费PDF全文
Employing the two-state model and the time-dependent wave packet method, the influence of femtosecond laser wavelength on the evolution of the double-minimum electronic excited state wave packet is numerically investigated. For different laser wavelengths, evolutions of the double-minimum electronic excited state wave packet with time and internuclear distance are different. One can control the evolution of the wave packet by varying the laser wavelength appropriately, which will benefit the light manipulation of atomic and molecular processes. Furthermore, study of the dynamics of the NaRb molecule may yield clues to creating an ultracold molecule. 相似文献
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TWAP与VWAP算法为两类较常见的经典交易算法.传统的VWAP算法在TWAP算法的基础上,大多使用预测日内成交量分布的方法指导算法下单.传统成交量分布的预测效果严重依赖于市场交易惯性,但交易量分布受到日内诸多突发因素的影响,导致算法对市场突发状况的应对能力较弱.本文对传统TWAP与VWAP算法进行改进,利用滚动的1分钟粒度高频实时资金博弈数据,基于Logistic分类器训练量价模型,以该预测结果为入参构建最优化期望执行均价模型,求出当下各个价格档位对应委托数量的最优解.通过相对高频的分钟级价格预测机制,保证算法实时跟踪市场行情走势并寻求相对优势的交易机会.该算法经测试可以稳定地跑赢市场均价,具备推广应用的可行性. 相似文献
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基于Poveda等计算得到的DMBE势能面,运用准经典轨线的方法研究了同位素取代和碰撞能对N(4S)+H2反应的立体动力学性质的影响.计算并讨论了两矢量k-J’相关分布函数P(θr),三矢量k—k'-j’相关分布函数P(φr),空间分布函数P(θr,φr),微分反应截面和积分反应截面.研究了碰撞能从25kcal/mol到80kcal/mol变化对三个反应N+H2,N+D2和N+T2的影响.结果表明:分子间同位素和碰撞能均会对反应立体动力学性质产生一定的影响. 相似文献
66.
Potential energy curves and analytical potential energy functions of the metastable states of B2^++ 下载免费PDF全文
The multi-reference configuration interaction method and aug-cc-pvqz (AVQZ) have been used to calculate potential energy curves (PECs) of the singlet and triplet states of the riu and rig symmetry of B2++. All of the four states (^l∏u, ^1∏g, ^3∏u and ^3∏g) are found to be metastable states, though the potential well of ^3∏u symmetry is very shallow. Based on the PECs, the analytical potential energy functions (APEFs) of these states have been fitted using the least square fitting method and two models of function. The spectroscopic parameters of each state are also calculated, and are compared with other investigations in the literature. The credibility and veracity of the two functions are evaluated. Some ideas to improve the fitting accuracy are presented. Also the vibrational levels for each state are predicted by solving the SchrSdinger equation of nuclear motion. 相似文献
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The stereodynamics of the reaction of Ca + HCl are calculated at three different collision energies based on the potential energy surface [Verbockhaven G et al. 2005 J. Chem. Phys. 122 204307] using quasi-classical trajectory theory. The polarization-dependent differential cross sections (PDDCSs) (2π/σ )(dσ 00 /dω t ), (2π/σ )(dσ 20 /dωt ), (2π/σ )(dσ 22+ /dωt ), (2π/σ )(dσ 21 /dω t ) and the distributions of P(θ r ), P(φr ), and P(θr ,φr ) are calculated. The results indicate that the rotational polarization of the CaCl product presents different characteristics for the different collision energies, and the effects of the collision energy on the vector potential, including the alignment, orientation, and PDDCSs, are not obvious. 相似文献
68.
杨传路黄钰 《原子与分子物理学报》2003,(2)
采用从头计算的耦合簇方法CCSD(T)和He原子Dunning’s相关调和基函数组对He2+团簇的结构参数、势能曲线进行计算。利用Murrell-Sorbie函数和最小二乘法拟合出了解析势能函数,并以此为基础计算出光谱常数。通过比较发现:分子结构和光谱常数计算结果均与实验值符合良好,优于文献报道的结果。说明本文所得势能函数解析表达式准确反映了分子中原子间相互作用,可用于更广泛的研宄。 相似文献
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为了全面了解柴油/甲醇组合燃烧(DMCC)的尾气排放特性,对比研究了原柴油机,DMCC模式以及加装了催化转化器的DMCC模式的常规排放物NOx、THC和CO以及非常规排放物一甲醛尾气排放特性.结果表明:采用DMCC燃烧方式,可以减少NOx排放,并且随着甲醇替代比率的增加, NOx进一步减少;与原机相比,采用DMCC模式THC和CO排放明显增加,加装催化转化器后,有不同程度的降低,在高负荷时催化转化器的转化效率比较高,为85%~92%,催化后两者排放接近原机水平;甲醛排放比原机时增加几十倍,催化转化器可以降低甲醛排放,但也会增加甲醛排放,其效果与排气温度密切相关.在排气温度较高时,催化转化器对THC、CO,甲醛均有较好的转化效果. 相似文献
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采用从头计算多参考组态CI方法(MRCI)研究了NaH分子的基电子态的内层电子相关对其分子特征的影响。计算了不同内层电子数目相关情况下的势能曲线,通过解析势能函数拟合,计算出了光谱常数。利用求解分子核运动薜定谔方程的方法,得出了振动能级。通过分析Na原子内层电子与价电子相互作用受H原子核影响的变化,对NaH分子的势能曲线、光谱常数和振动能级等特征量随相关电子数目的变化作了合理的解释。 相似文献