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1.
高压下材料弹性声速的一种经验表达式   总被引:1,自引:1,他引:0  
 将铝、铁、铜等七种材料弹性声速的实测数据进行分析处理发现,其弹性声速随压力的变化均可以用一下关系:ln c=A0+A1ln p+A2ln2p,很好的拟合。拟合结果与实测值的相对误差小于5%。  相似文献   

2.
凝聚炸药中超压爆轰的实验研究   总被引:1,自引:1,他引:0       下载免费PDF全文
 采用飞片碰撞技术,在TNT/RDX(40/60)炸药中获得了2.5倍于正常爆轰的最大超压值,得到了超压爆轰下爆轰产物物态方程p=Aρk+A1(p-pJ)(p-爆压,单位GPa,ρ-密度,单位kg/m3,A=ρJkJ,pJ=27.06 GPa,ρJ=2.3×103 kg/m3,k=2.77,A1=2.7×10-3 GPa-1,下表J代表正常爆轰状态)。该方程还可以较好地描述超压爆轰产物的二次冲击状态。  相似文献   

3.
铜的高压声速和冲击熔化   总被引:4,自引:4,他引:4       下载免费PDF全文
 用光分析技术,测量了在一维应变冲击条件下,无氧铜的高压下声速,压力范围为125~170 GPa。将上述结果与Broberg、Morris等和Aльгшуер等过去发表的数据结合在一起,对0~170 GPa整个压力区间的声速数据做了综合分析,给出了声速随压力的变化规律。实验结果发现,无氧铜在156~159 GPa之间开始发生冲击熔化,到170 GPa左右,完全进入液相区;对于处于0~156 GPa固体无氧铜的弹性声速cl可用ln cl=1.565 888-2.645 488×10-2ln p+2.710 681×10-2ln2p拟合公式描述(p的单位为GPa,cl的单位为km/s),拟合值与实验值的相对误差小于1.3%。  相似文献   

4.
本文内容包括:(ⅰ)进一步给出SU(2)×U(1)×S3模型的结果S2≈S3≈(ms2)/(mb2);sin δ≤(mumd)/(mcms),并预言b夸克的主要衰变道是b→u+W,b夸克的寿命可能长到10-9秒.(ⅱ)给出类K0-K0系统混合时的精确表达式ρ=错号事例数/对号事例数=(1/2)(|p/q|2+|q/p|2)([Γ2+(Δm)2]2-(γ1γ2)2)/([Γ2+(Δm)2]2+(γ1γ2)2);并给出CP破坏的精确表达式:A=(1-ρ')/(1+ρ')=(IM12Γ12*)/(|M12|2+1/4|Γ12|2),这里ρ′=(负电错号事例数)/(正电错号事例数)。  相似文献   

5.
锰铜压力计的灵敏度   总被引:1,自引:1,他引:0  
 文中根据K. Yosida对锰铜合金电阻率的理论,认为电阻率和下列各量成比例关系:ρ∝VDS/Ef,式中Ef是电子的费米能,V为导体体积,S为锰离子的自旋,D为交换积分函数。代入计算电阻的公式,求得ΔR/R=ΔD/D-ΔEf/Ef+ΔS/S+2ΔV/(3V),然后文中分别求出了上式中后边前三项和ΔV/V的关系,最后利用静力压缩曲线求得ΔR/R和流体静压力p的关系为:ΔR/R0=2.41×105×p (Pa),流体动压力关系为:ΔR/R0=2.8×105×p (Pa),和实验结果进行了比较,十分符合。  相似文献   

6.
对于自旋巨偶极共振,本文考虑了核场(Y0δ11v和γ2(Y2δ11v之间的耦合项的影响,这种耦合形式可以从张量算符给出.对于λ≥2的自旋巨共振,本文考虑了核场γλ+1(Yλ+1δ1)λv的影响.  相似文献   

7.
SiC1-xGex/SiC 异质结光电二极管特性的研究   总被引:5,自引:5,他引:0  
使用二维器件模拟软件Medici, 对SiC1-xGex/SiC异质结的光电特性进行了模拟.设计了N型重掺杂SiC层的厚度为1 μm, P型轻掺杂SiC1-xGex层厚为0.4 μm, 二者之间形成突变异质结.在反向偏压3 V、光强度为 0.23 W/cm2的条件下, p-n+ SiC0.8Ge0.2/SiC和p-n+ SiC0.7Ge0.3/SiC敏感波长λ分别可以达到0.64 μm和0.7 μm, 光电流分别为7.765×10-7 A/μm和7.438×10-7 A/μm; 为了进一步提高SiC1-xGex/SiC 异质结的光电流, 我们把p-n+两层结构改进为p-i-n三层结构.在同样的偏压、光照条件下, p-i-n SiC0.8Ge0.2/SiC和p-i-n SiC0.7Ge0.3/SiC的光电流分别达到1.6734×10-6 A/μm和1.844×10-6 A/μm.  相似文献   

8.
Recently an f-deformed Fock space which is spanned by |n〉λ was introduced. These bases are the eigenstates of a deformed non-Hermitian Hamiltonian. In this contribution, we will use rather new non-orthogonal basis vectors for the construction of coherent and squeezed states, which in special case lead to the earlier known states. For this purpose, we first generalize the previously introduced Fock space spanned by |n〉λ bases, to a new one, spanned by extended two-parameters bases |n〉λ12. These bases are now the eigenstates of a non-Hermitian Hamiltonian Hλ1,λ2=aλ1,λ2+a+(1/2), where aλ1,λ2+=a++ λ1a + λ2 and a are, respectively, the deformed creation and ordinary bosonic annihilation operators. The bases |n〉λ12 are non-orthogonal (squeezed states), but normalizable. Then, we deduce the new representations of coherent and squeezed states in our two-parameter Fock space. Finally, we discuss the quantum statistical properties, as well as the non-classical properties of the obtained states numerically.  相似文献   

9.
镀膜锰铜计的压阻性能研究   总被引:4,自引:2,他引:4       下载免费PDF全文
 用磁控阴极等离子体溅射技术在云母基底上制作镀膜锰铜压阻计。5~56 GPa冲击应力的标定实验表明,该计的压阻性能稳定。压阻系数的拟合式为p(GPa)=-0.14+90.63(ΔR/R0)+10.81(ΔR/R0)2-7.64(ΔR/R0)3,式中R0为锰铜计初始电阻,ΔR为受压时的电阻变化值。  相似文献   

10.
在海拔3220米的实验室里,用磁谱仪动量予选装置和多板云室,对落在0.23m2面积上的单根荷电强子进行了观测.考虑到各种可能的修正以后,得出在10—20 GeV/c之间,荷电强子的负正比为:N-/N+=0.53±0.05.当认为N+只包含有P和π+,N-是π-,而且Nπ+/Nπ-=1时,推算出Nπ-/Np=0.9±0.1.若π-积分谱的形式为j(>p)=Kp-r,估算出在5—20 GeV/c的动量范围,r(?)2.3.本文也对荷电强子的积分流强作了粗略的估计,其结果是:jp+π(>12 GeV/c)=(7.4±0.7)×10-5cm-2·st-1·s-1.  相似文献   

11.
A method for finding potentials corresponding to polynomial-factor eigenfunc-tions is given for the Schr(?)dinger equation as an example.It is shown that theeigen-solutions for harmonic and Columb's potentials in quantum mechanics are the twoexamples which can be given by this method and some other examples are discovered.This method and some results of this paper may be useful for hadron structure mo-del theory.One of the examples is the equation in Ref.(4)which is derived fromBethe-Salpeter equation for the case that the straton is tightly bounded in certain po-tential well.When this method is applied to that equation for three dimensionalcentral symmetric potential V(r)=V0—2(N+(1/2))β-1(√V6r2)+(V6r6), some resultsare obtained as shown in Fig. 2 in which λ′ must be considered as a linear function of m2.The so called“quasic Regge trajectory”behavior is manifested.  相似文献   

12.

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   

13.
提出了计算苯甲醛亚胺、N-苯基亚胺、N-甲基亚胺、N-异丙基亚胺中亚胺基氮原子15N NMR化学位移的经验公式:δcal0n+Δα+Δβ+Δγ+c. 按亚胺基氮原子和碳原子上两类取代基的不同分别结合最小二乘法通过线性回归各得到5种取代基参数,计算结果分别以其化学位移数据为样本点作回归检验,置信度为99.5%,最大误差Δδ≤3.1,大约有95%的15N NMR化学位移计算值的计算误差小于3.0(相对误差小于0.3%). 初步分析了芳香族亚胺苯环上对位取代基对亚胺基氮原子化学位移的影响.  相似文献   

14.
提出了计算取代苯甲酸羧基17O NMR化学位移的公式:δcal17O)=250.0+Δo+Δm+Δp,通过线性回归法确定了8种取代基参数.经回归检验表明该公式计算结果置信度为99.5 %,羧基17O NMR化学位移计算值与实验值的偏差Δδ全部在2.0以内.  相似文献   

15.
The Bethe-Salpeter equation for an electromagnetic bound system of spins (1/2—1/2) or (1/2—1/2) with unequal masses are solved in this paper. The approximate B.S. wave functions for these systems are given. Utilising these wave functions, the decay rate and branching ratio for Ξ0→(Σ+μ)+vμ are calculated with accuracy up to order O(α). The results are wΞ0→(Σ+μ)+vμ1.12(1/sec) and R=[wΞ0→(Σ+μ)+vμ]/[wΞ0→(Σ+μ)+vμ]4.7×10-7. Similarly, the process Λ→(pμ)+vμ is also discussed.  相似文献   

16.
函数的H-导数和分形动力学   总被引:2,自引:1,他引:1       下载免费PDF全文
 给出了函数的Hausdorff测度与H-导数。从而,为开展自给的分形动力学提供了解析的数学工具。同时,给出了分形动力学的演化方程组并做了初步讨论与分析。  相似文献   

17.
提出了计算取代苯甲酸甲酯类化合物羰基17O-NMR化学位移的公式:δcal(17O)=337.3+Δo+Δm+Δp, 根据52种取代苯甲酸甲酯类化合物的52个羰基17O-NMR化学位移数据, 通过线性回归法结合最小二乘法求得22个用于该公式的取代基参数, 回归检验表明采用该公式计算结果的置信度为99.5 %,计算值与实验值的偏差Δδ在5.0以内的~100 %.  相似文献   

18.
We calculate the branching ratios of pure annihilation type decays B0→Ds- K2*+ and BsDa2 using the perturbative QCD approach based on kT factorization. The branching ratios are predicted to be (60.6-16.5-10.4-2.1+17.3+4.3+3.2 )× 10-6 for B0→Ds- K2*+, (1.1-0.4-0.2-0.1+0.4+0.1+0.1)×10-6 for BsD0a20 and (2.3-0.8-0.4-0.1+0.8+0.2+0.1)×10-6 for Bs→D-a2+. They are large enough to be measured in the ongoing experiment. Due to the shortage of contributions from penguin operators, there are no direct CP asymmetries for these decays in the Standard Model. We also derive simple relations among these decay channels to reduce theoretical uncertainties for the experiments to test the accuracy of theory and search of new physics signal.  相似文献   

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