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1.
The symmetry of group U(3) can be used to get the rotationvibrational spectra of a diatomic molecule without solving the schroedinger equation.  相似文献   

2.
In this paper, some decomposotion formulas of γ-type matrices are derived based on Gordon identities. As an illustration of the application of these formulas, the one gluon exchange potential between quark and antiquark is rederived which appears to be different from that obtained by Faessler, et al. As another illustration, the correct reduction of the γ-matrices appearing in the kernel function of Bethe-Salpeter equation for quark-antiquark system is achieved and yields an expression different from that derived by Mitre whose calculation was grounded on a wrong decomposition formula for one γ-type matrix.  相似文献   

3.
The theory of the smooth-average field in shallow water is presented;the smooth-average expres-sion suitable for long ranges and the image-source expression suitable for short ranges are combinedtogether to give a more complete calculating method of the average field.The correspondingcomputer programs,which make the calculation of the average field easy and rapid,have heendeveloped.Some examples of application of the method are given,and the calculated results arequite consistent with the experiments.  相似文献   

4.
Excitation curves for the reaction 27Al(n,α24Na,46Ti(n,p46Sc,48Ti(n,p48Sc,51V(n,α48Sc and 127I(n,2n126I have been measured by the activation method in the4.5—18.3 MeV energy region.The cross section for the reactio 27Al(n,α24Na was determined at 14.61±0.20 MeV.The measurement of neutron flux was performed using the associated particle method.The cross sections for other reactions were de-termined relative to the measured 27Al(n,α24Na cross section.The resulting activities were measured employing a calibrated NaI(TI)scintillation counter.The values obtained were 117.5±3.0 mb,291.4±14.0mb,63.7±3.2 mb,16.8±0.9mb and 1656±68 mb respectively.A brief comparison with existing data was made.  相似文献   

5.
陶必修 《中国物理》1999,8(7):481-484
The existence and evolution of spherical membrane configurations in spherical-symmetric and self-similar spacetimes are studied, and a solution for the dynamics of membranes is obtained. A new interpretation for the origin and evo lution of the cosmic matter-structures is acquired. It agrees well with the survey of astronomy.  相似文献   

6.
In this paper, a recurrent formula for α-row partition is given. Using this formula, we get the multiplicities of all sorts of coupling states in shell-model. It has been proved to be very efficient in simplifying the ealculations concerned.  相似文献   

7.
The overlap of magnetization of the giound state in a RKKY spin glass system with the Dzyaloshinsky-Moriya interaction is studied based on the theory of infinite number of order parameter. It is shown that the nonmagnetic impurities are coupled with the host lattice.The results are in good agreement with experiments.  相似文献   

8.
Although the pitch is different in absolute value the pitch contour corresponding to a particularChinese tone should have a similar pattern which is a distinctive feature in speech perception.Thisis an important feature of Chinese language itself. A lot of work on the pitch pattern of Chinese tones has been done,but most of them were onlyqualitative or oversimplified.It is somewhat difficult to apply those results directly to design ofspeech synthesis by rule.This paper has given 15 new statistical results of tone patterns of Chinesedisyllable and each pattern can be formulated simply by a normalized function P(t)in time domainwhich is directly proportional to T_0_(max) and inversely proportional to T_0(t),where T_0_(max) is thereciprocal of the lowest fundamental frequency in the syllable and T_0(t)the pitch period at time t. It has been shown that there are some characteristics in tone pattern of Chinese disyllable: (l) At the beginning and the end of every tone pattern there is always a transient proc  相似文献   

9.
The equation of infrasonic wave taking into account the gravitational effect in moving media isderived,with multi-layer atmospheric model.The equations of frequency dispersion are specified bydivergence of velocty,using a multi-layer atmospheric model.The dispersion characteristic ofacoustic-gravity wave is evaluated.Numerical results have shown that both the phase and groupvelocities are different two,the acoustic and gravity-waves.The dispersion of the acoustic velocitiesare more sensitive to wind.Usually the short period group velocity in downwind can differ aslarge as 10% from that in upwind.In some atmospheric model,the gravity-waves velocities areagain divided to several groups,with different dispersion characteristics.The new results of infrasonicdispersion characteristics agree well with the observations from the nuclear explosion.  相似文献   

10.

In the framework of the perturbative QCD, the two-fold differential cross section d2σ/dxTdxL of the reaction γ+p→2γ+X and its two backgrounds (γ+p→γ++X, γ+p→γ++X) are calculated in c.m.s.. The results show that, in a large range of (xT, xL), the calculated reaction cross section can be measured in current laboratory condition. And due to the properties of this reaction, i.e., large pT photoproduction and direct photon pair emission, all of the backgrounds can be greatly suppressed.

  相似文献   

11.
用于IGCC的燃气轮机技术方案与性能预测   总被引:4,自引:2,他引:2  
主要符号表T温度G质量流量。压气机压比。压气机进口导叶安装角N功率X。压损系数X。。氮气回注系数X。;,空分整体化系数下标a空气cg煤气0烧天然气时设计工况。氮气as空分装置f燃料O。氧气1Bu8整体煤气化联合循环(IGCC)燃气轮机与常规的燃机有很大的差异[“l。它改烧中低热值的合成煤气,其燃料量比烧高热值的油气时要增大几倍;不同空分方案和采用不同的NZ回注掺混量时,情况就更为复杂。透平工质流量比压气机空气流量相差很多,燃气轮机总是处于复杂的变工况状态。2IGCC中燃气轮机技术方案归纳IGCC中燃气轮机可行的技术方案…  相似文献   

12.
使用分于轨道从头算方法,在MP2(fu)/6—31G优化几何基础上,采用HF,MPn(n=2,3,4)和QCISD(T)理论,使用6—31G(d,P),6—311G(d,P),6—31G(Zdf,P)和6—311+G(3df,2p)基组,计算了NaS和Na2S分子以及Na和S原子的总能量和各级电子关联修正能。在此基础上应用G1和G2理论估算TNaS和Na2S分子的解离能和生成热。在G2理论框架下,理论估算的解离能和生成热(在室温)分别是67.07kcalmol-1和0.35kcalmol-1(Na2S)以及50.48kcalmol-1和41.57kcalmol-1(NaS)。  相似文献   

13.
为饱和醛酮类化合物的13C核磁共振波谱模拟.根据该类化合物的特点,提取了分子的拓扑特征,几何特征及电子特征.应用变量最优子集回归法进行了变量的选择,并用这些变量构造了回归模型.交叉验证的结果表明,所得数学模型比较稳定,并得到了较好的预测结果。  相似文献   

14.
环保制冷剂表面张力的预估方程   总被引:1,自引:1,他引:0  
表面张力是有沸腾和凝结的换热计算必不可少的物性参数,作为制冷剂替代物,HFC和HCFC物质的表面张力数据对于制冷空调设备的设计十分重要。本文应用对比态原理和重正化群理论,提出了一种新的HFC和HCFC物质表面张力的预估方程,可以在广阔的温度范围内高精度地再现实验数据,计算精度可满足工程实际需要,并与国际上现有的关联式进行了比较分析。  相似文献   

15.
根据镁和硼的基本化学性质、杂化轨道理论、前线轨道理论和粉末反应理论,分析了粉末反应中MgB2晶核的形成及生长过程.这一过程可分为三步完成:1.两种粉粒碰撞接触后,做反相微幅受迫振动,这种振动产生晶核的形成及生长区;2.两个硼原子相遇,价轨道经sp2杂化后形成B2,镁原子的两个3s价电子填入B2的π轨道形成π键,生成Mg...  相似文献   

16.
当离子蒸气冷凝形成团簇时,其结构表现出特定的规律。文中对不同大小不同形状的氯化钠团簇结构与结合能进行了计算,以求揭示离子蒸气冷凝形成团簇的一些规律,并与实验结果进行对照。  相似文献   

17.
文献[1]中提出了一个新的势函数,其Schrdinger方程严格可解。同时提出一个新的变量变换关系,用超几何级数严格求解了双曲型PschlTeler分子势Schrdinger方程的束缚态。文内进一步讨论这两个势函数Schrdinger方程散射态的严格解,并求出了S波的散射相移。文献中关于修正PschlTeler势及无反射势散射态的结果均作为特例包含在这篇文章更一般的结论之中。此外还用一个简单的方法考虑了转动能修正,对HF基态转动谱作了具体计算  相似文献   

18.
用模拟和实验相结合的方法研究了挥发分的均相反应、温度等因素对N2O、NO生成与分解的影响。研究发现,挥发分主要通过分解反应影响N2O的排放量,而主要通过生成反应影响NO的排放量。与高挥发分煤混合燃烧时,不仅N2O生成量降低,氮生成N20的总体转化率也下降。N2O的经时特性要经历一个从生成到分解的过程。  相似文献   

19.
第二代增压流化床联合循环发电技术(2G PFBC-CC)是当前具有应用前景的洁净煤发电技术之一。东南大学热能工程研究所构建了2 MWt加压喷动流化床部分气化炉,对原有1 MWt增压流化床燃烧炉进行了改造,形成了较完整的2G PFBC-CC系统.经过二年多的调试和试验研究,验证了2G PFBC-CC工艺可行性和先进性,部分气化炉产生的煤气热值在4.2 MJ/Nm3以上,满足燃气透平的要求,排出的半焦可在PFB燃烧炉内稳定燃烧,飞灰含碳量在2%以下,系统碳利用效率在99%以上。  相似文献   

20.
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