自由电子的C—M量子放大效应

重新推导和研究了C-M(Chang-McDaniel)效应的主要公式,指出C-M效应需要α、k_8和k_0满足的匹配条件。     

从A—B效应到A—C效应

本综述了Ａ－Ｂ效应和Ａ－Ｃ效应以及它们之间的对偶关系，并介绍了对Ａ－Ｃ效应的实验验证。     

2—（2—取代苯基丙烯基）—5—取代苯并恶唑的光性质研究

本文测试了２０个标题化合物的紫外光谱和荧光光谱，讨论了它们的取代基效应，研究了１６种溶剂对其中两个化合物的紫外光谱的溶剂效应以及一个化合物的光反应。     

1—(3—吡啶甲酰)—4—芳基氨基硫脲类和3—(3—吡啶基)—4—芳基—1,2,4—三唑啉—5—硫酮类化合物~(13)C—NMR谱研究

本文测定了1-(3—吡啶甲酰)—4—苯基氨基硫脲、3—(3—吡啶基)—4—苯基—1,2,4—三唑啉—5—硫酮等8个新化合物的~(13)C NMR谱,运用质子宽带去偶、偏共振去偶,结合信号强度对比、苯基取代基效应的计算,同时与模型化合物对照,一一归属了其谱峰。本文对这两类化合物之间的~(13)C NMR谱差异进行了探讨,并得到了在吡啶环3位取代的甲酰肼基对吡啶环各碳取代基效应的数据。     

1—(4—吡啶甲酰)—4—芳基氨基硫脲类和3—(4—吡啶基)—4—芳基—1,2,4—三唑啉—5—硫酮类化合物~(13)C—NMR谱研究

本文测定了新合成的,具有生理活性的1-(4-吡啶甲酰)-4 -苯基氨基硫脲,1-(4-吡啶甲酰)-4-对氯苯基氨基硫脲,1-(4 -吡啶甲酰)-4-对溴苯基氨基硫脲3-(4-吡啶基)-4-苯基-1,2,4,-三唑啉-5-硫酮,3-(4-吡啶基)-4-对氯苯基-1,2,4,-三唑啉-5-硫酮,3-(4-吡啶基)-4-对溴苯基-1,2,4-三唑啉-5-硫酮六个新化合物的~(13)C-NMR谱,并通过~(13)C-NMR谱中的宽带去偶,偏共振及APT技术,模型化合物对照,讯号强度对比及芳基取代基常数计算等方法,进行了上述化合物~(13)C-NMR谱峰的归属,并得到了甲酰肼基在吡啶环4位取代后对吡啶环各碳所产生的取代基效应.     

相对论效应对电子—原子弹性散射的影响

本文用出现在薛定谔方程中的一个“等效势”体现相对论效应,结合我们以前得到的交换势,计算了低能电子(0.1-30eV)被Ar、Kr、Xe、Rn弹性散射的截面。结果表明,相对论效应的影响随原子序数的增加而加大。考虑相对论效应后计算结果与实验符合得很好,这也同时表明我们所用的交换势是较成功的。     

电—流变效应演示实验

一、电-流变效应简介早在40年代,美国物理学家Wills.Winslow发现,把某些材料粉末分散在矿物油中制成悬浮液,当施加电场时,其表观粘度及剪切应力随电场的变化而变化。由于在电场作用下该流体呈现非牛顿流体的特点,故称电-流变效应(ER)。电-流变效应的意义在于,可以把这种流体做为一种传动介质,应用于离合器、减     

浅谈狭义相对论的三个效应

狭义相对论中由"光速不变"而产生了三个常见的相对论效应:时间膨胀、长度收缩和同时的相对性.实际上,光速不变原理所导致的效应不止这些,下面就介绍三个很有意思的相对论效应:前灯效应(headlight effect)、光行差效应(aberration effect)和角压缩效应(angular compresson effect).     

单磁场驱动的Tb1-xDyxFe2-y/Pb(Zr,Ti)O3三层膜磁电效应

研究了Tb1-xDyxFe2-y(TDF)与锆钛酸铅(PZT)三层膜样品的制备和在单一直流磁场驱动下的磁电(ME)效应.在该系列三层膜样品中测量到了巨大的ME耦合效应.所得实验结果与同种样品在两磁场驱动下的ME效应完全不同.这可能预示了某些新的物理内容.该技术可简化ME效应在某些实际应用中的复杂度.     

Aharonov-Bohm效应与电磁基础理论教学的改革

1959年，阿哈罗诺夫(Y．Aharonov)和玻姆(D.Bohm)提出了一个理想实验，这个实验揭示了电磁场的势具有直接可观测的物理效应．即在电磁场场强为零，但电磁场的势不为零的区域，电磁势的作用会使电子波函数的相位发生改变．这种由电磁场的势所引起的量子效应，被称作Aharonov-Bohm效应，又简称为A-B效应．     

Theoretical Study of the Collision-Induced Double Transition CO(2) (nu(3) = 1) + N(2) (nu(1) = 1) <-- CO(2) (nu(3) = 0) + N(2) (nu(1) = 0) at 296 K

A procedure is presented for the calculation of the double vibrational collision-induced absorption CO(2) (nu(3) = 1) + N(2) (nu(1) = 1) <-- CO(2) (nu(3) = 0) + N(2) (nu(1) = 0) on the basis of quantum lineshapes computed using an isotropic potential and dipole-induced dipole functions. The linestrengths and energies of the vibration-rotation transitions are treated explicitly for N(2), utilizing the HITRAN database for CO(2). The theoretical absorption profile is compared to recent experimental results. By narrowing the width of the individual lines contributing to the overall absorption profile relative to their values determined for N(2)-N(2) collision-induced absorption, excellent agreement between theory and experiment is obtained. Copyright 2000 Academic Press.     

First Observation of the nu(17)-nu(4) Difference Bands of Diborane (10)B(2)H(6) and (11)B(2)H(6)

An analysis of the nu(17)-nu(4) difference bands near 800 cm(-1) of two isotopic species, (10)B(2)H(6) and (11)B(2)H(6), of diborane has been carried out using infrared spectra recorded with a resolution of ca. 0.003 cm(-1). In addition, the nu(17) band of (10)B(2)H(6) has been recorded and assigned. Since this band in (11)B(2)H(6) had already been studied (R. L. Sams, T. A. Blake, S. W. Sharpe, J.-M. Flaud, and W. J. Lafferty, J. Mol. Spectrosc. 191, 331-342 (1998)), it was possible to derive precise energy levels and Hamiltonian constants for the 4(1) vibrational states of both isotopic species. Copyright 2000 Academic Press.     

The 2(3)Delta(g) State of (7)Li(2)

Using pulsed perturbation-facilitated optical-optical double resonance (PFOODR) spectroscopy, the 2(3)Delta(g) state of (7)Li(2) (electronic configuration (varsigma(g)2s) (4ddelta(g)), effective principal quantum number n* = 4.101) has been observed and assigned. Molecular constants and a RKR potential energy curve were obtained. The major molecular constants are Copyright 2000 Academic Press.     

The Perturbation between the G(1)Pi(g) and 2(1)Delta(g) States of (7)Li(2)

We have observed the rotational levels in the v = 2, 3, 5, 6, 7, and 8 vibrational manifolds of the 2(1)Delta(g) state of (7)Li(2) via the A(1)Sigma(+)(u) intermediate levels by DeltaLambda = 2 transitions. This violation of the DeltaLambda = 0, +/-1 selection rule is due to the interaction with the G(1)Pi(g) state. Band-by-band deperturbations of the G(1)Pi(g) approximately 2(1)Delta(g) (v(Pi), v(Delta)) = (11, 2), (12, 3), (15, 5), (16, 6), (18, 7), and (19, 8) bands have been performed. Deperturbed molecular constants and rotational-electronic interaction parameters are reported here. Copyright 2000 Academic Press.     

Rovibrational Intensities of the (00(0)3) <-- (10(0)0) Dyad Absorption Bands of (12)C(16)O(2)

Absolute line intensities of (12)C(16)O(2) are experimentally measured for the first time for the (00(0)3)(I) <-- (10(0)0)(II) band at 5687.17 cm(-1) and the (00(0)3)(I) <-- (10(0)0)(I) band at 5584.39 cm(-1). The spectra were obtained using a Bomem DA8 Fourier transform spectrometer and a 25-m base-path White cell at NASA-Ames Research Center. The rotationless bandstrengths at a temperature of 296 K and the Herman-Wallis parameters are S(0)(vib) = 6.68(30) x 10(-25) cm(-1)/(molecule/cm(2)); A(1) = 1.4(9) x 10(-4), and A(2) = -1.1(5) x 10(-5) for the (00(0)3)(I) <-- (10(0)0)(II) band and S(0)(vib) = 6.07(22) x 10(-25) cm(-1)/(molecule/cm(2)); A(1) = 5.2(1.5) x 10(-4) and A(2) = -4.0(7) x 10(-5) for the (00(0)3)(I) <-- (10(0)0)(I) band.     

CO2同位素分子16O12C16O, 16O12C17O, 16O13C17O配分函数研究

本文主要研究了CO2的三种同位素分子16O12C16O , 16O12C17O ,16O13C17O 70 K~6000 K的总内配分函数 (TIPS)。在总内配分函数的计算中, 转动配分函数的计算采用了McDowell的解析式法, 振动配分函数则采用了简谐振动近似(HOA)获得。最后通过将两配分函数乘积近似计算得出TIPS, 并将其70~3000 K的数据和HITRAN04数据进行了比较, 发现所得结果和数据库符合的较好, 且其误差可以近似看成一条直线。并通过对误差的拟合修订了高温区(3000~6000 K)的计算数据, 给出了在高温下的较为准确的TIPS值。     

The v(1)+v(3) Bands of the (16)O(17)O(16)O and (16)O(16)O(17)O Isotopomers of Ozone

Using 0.002 cm(-1) resolution Fourier transform absorption spectra of an (17)O enriched ozone sample, an extensive analysis of the v(1)+v(3) bands of the (16)O(17)O(16)O and (16)O(16)O(17)O isotopomers of ozone has been performed for the first time. The experimental rotational levels of the (101) vibrational states were satisfactorily reproduced using a Hamiltonian matrix that takes into account the observed rovibrational resonances. More precisely, for (16)O(17)O(16)O, as for the other C(2v)-type ozone isotopomers, it was necessary to account for the Coriolis type resonances linking the (101) rotational levels with the levels of the (200) and (002) vibrational states and the Darling-Dennison interaction coupling the levels of (200) with those of (002). For the C(s)-type isotopomer, namely (16)O(16)O(17)O, as for (16)O(16)O(18)O and (16)O(18)O(18)O, it proved necessary to also account for an additional DeltaK(a)&equals+/-2 resonance involving the rotational levels from (101) and (002) (J.-M. Flaud and R. Bacis, Spectrochimica Acta Part A 54, 3-16 (1998)). Using a Hamiltonian matrix which takes these resonances explicitly into account, precise vibrational energies and rotational and coupling constants were deduced, leading to the following band centers: v(0)(v(1)+v(3))=2078.3496 cm(-1) for (16)O(17)O(16)O and v(0)(v(1)+v(3))=2098.8631 cm(-1) for (16)O(16)O(17)O. Copyright 2001 Academic Press.     

Multiple magnetic transitions in single crystals of Ce_(12)Fe_(57.5)As_(41) and La_(12)Fe_(57.5)As_(41)

Measurements of magnetic and transport properties were performed on needle-shaped single crystals of Ce_(12)Fe_(57.5)As_(41)and La_(12)Fe_(57.5)As_(41).The availability of a complete set of data enabled a side-by-side comparison between these two rare earth compounds.Both compounds exhibited multiple magnetic orders within 2-300 K and metamagnetic transitions at various fields.Ferromagnetic transitions with Curie temperatures of 100 and 125 K were found for Ce_(12)Fe_(57.5)As_(41)and La_(12)Fe_(57.5)As_(41),respectively,followed by antiferromagnetic type spin reorientations near Curie temperatures.The magnetic properties underwent complex evolution in the magnetic field for both compounds.An antiferromagnetic phase transition at about 60 K and 0.2 T was observed merely for Ce_(12)Fe_(57.5)As_(41).The field-induced magnetic phase transition occurred from antiferromagnetic to ferromagnetic structure.A strong magnetocrystalline anisotropy was evident from magnetization measurements of Ce_(12)Fe_(57.5)As_(41).A temperature-field phase diagram was present for these two rare earth systems.In addition,a logarithmic temperature dependence of electrical resistivity was observed in the two compounds within a large temperature range of 150-300 K,which is rarely found in 3D-based compounds.It may be related to Kondo scattering described by independent localized Fe 3d moments interacting with conduction electrons.