新疆山地森林鸟类的分布及食性和营巢特征的初步研究

通过对新疆山地森林鸟类的考察和研究,将其归结为137种另30亚种,对其分布特征、栖境、食性、营巢进行了研究,并发现鸟类的分布对山地森林的发育情况呈现出某种一致性.     

An unusual case of acute disseminated encephalomyelitis confined to brainstem

Acute disseminated encephalomyelitis (ADEM) is an immune-mediated demyelinating disorder usually encountered in children or adolescents and characterized by multifocal neurological deficits of rapid onset. Typical target areas of demyelination include the corona radiata, centrum semiovale, periventricular white matter, cerebellar peduncles and brainstem. Involvement of deep gray matter nuclei is also frequent. We report a 6-year-old boy with ADEM who had only brainstem involvement. Serial magnetic resonance images representing the stage of disease and response to steroid treatment are presented.     

Transient adaptivity applied to two-phase incompressible flows

An anisotropic adaptation process is applied to a three-dimensional incompressible two-phase flow solver. The solver uses a level set/finite element method on unstructured tetrahedral meshes. We show how the level set function can be used to build an anisotropic mesh with good properties. Some computations with a strong transient character and large densities ratios (1/1000) are presented. We show that the efficiency of the computations can be deeply enhanced by mesh adaptations.     

124Sn target residues in the interaction of heavy ions at intermediate energies

Cross sections, recoil energy distributions for residues produced by¹⁴N,²⁰Ne,⁴⁰Ar on¹²⁴Sn targets have been measured in the 10–70 MeV/u intermediate energy range. As the projectile energy increases, processes as complete fusion-evaporation, incomplete fusion-evaporation and intranuclear cascade-evaporation participate progressively in the nuclear collisions. Peculiar residues corresponding to a gain of 4, 5 or even 6 protons for the¹²⁴Sn target have been observed in the 30–50 MeV energy range.     

Etude d'impulsions lumineuses breves par interferometrie a deux ondes

We have studied the evolution of the light transmitted through matter in which an optical breakdown is taking place. With a two-waves interferometer made a birefringent plate between polarizers we get informations about the time correlation function of the fields. With an interferometer made of two identical harmonic generating plates separated by a dispersion medium, we learn about the correlation function of the square of the fields. Both systems act as spectral filters with a notch cosine-shaped centered at the incident frequency. We have also observed a transient angular spreading of the beam not previously emphasized which brings a further complication in the picture.     

利用喇曼光谱测量氧碘化学激光器氯气利用率的实验研究

 介绍了利用自发喇曼散射光谱测量氧碘化学激光器单态氧发生器氯气利用率的原理及实验装置，并给出了在以氮气作为稀释气的0.1mol/s射流式氧发生器上测试的结果，测试相对误差小于12%。由于该方法只需要通过测量喇曼谱线相对强度之比，即可算出氯的利用率，因此不需要另外的标定实验，从而避免了因标定带来的影响。该方法减小了测试误差，简化了实验过程，提高了测试效率。     

Single-ion approach to the susceptibility of an intermediate valence compound paramagnetic Imse

The magnetic properties of an intermediate valence compound are discussed within a single-ion framework. The effects of configuration mixing, crystalline electric fields, and external magnetic fields are included in the hamiltonian. The method incorporates in one single consistent approach both coherent (quantum) and incoherent (thermal) fluctuations. Numerical evaluation of the susceptibility and field dependent magnetization with parameters appropriate for TmSe yields results in good agreement with experiment.     

On the convergence of the Zassenhaus formula

The domain of convergence of the Zassenhaus formula in a Banach algebra is studied. This domain is shown to be strictly larger than the one which was already known.     

相对论激光在Maxwell分布等离子体中产生的高次谐波

 研究了强激光与具有初始速度分布的等离子体作用产生的高次谐波。结果表明，对于Maxwell速度分布的等离子体，由于电子初始时刻的无规则热运动，在一定程度上抹平了辐射功率在谐波谱上的分布，使得高次谐波的辐射增强，低次谐波的辐射有所减弱，有利于高次谐波的产生。