原子核反应和核结构

本文共分两部分:第一部分是叙述如何从原子核单独能级的特性和系统性来研究原子核的结构,并例举了四类研究这些能级最重要的原子核反应实验。第二部分主要是叙述如何从激发能高于中子或质子结合能的原子核内部运动的统计规律,来研究原子核的结构;并例举了六类研究虚激发态的原子核反应。作者对这两部分原子核反应实验今后的工作方向,提出了一些看法和意见。     

B-B Mixing in Dynimically Broken Theory

The B_d-B_d mixing is investigated in a dynamically broken electroweak theory such as the minimal technicolor theory with a monophagic coupling of quarks and pseudo-Goldstone bosons. The contrbutions of the technicolor pseudo-Goldstone bosons, enhanced by QCD color fowors, dominate the process for a wide range of parameters. If the topdown quark Kobayashi-Maskawa matrix element is not near the minimal allowed value, the pseudo-Goldstone bosone plus W boson can adequately account for the observed mixing large of the pseudo-Goldstone boson and top quark mass.     

ON THE MECHANISM OF QUENCHING OF SINGLET OXYGEN BY AMINES-III. EVIDENCE FOR A CHARGE-TRANSFER-LIKE COMPLEX

Abstract— A series of amines were found to quench singlet oxygen in the order tertiary > secondary > primary, with a reasonable correlation between the log of their rate constant of quenching and their ionization potential. In addition, a Hammett rho plot gave a rho value of - 1.39 for the quenching of singlet oxygen by a series of substituted N, N-dimethylanilines, in good agreement with the results obtained by a different method. It was found that some of the amines (anilines) quenched the triplet state of the dye-sensitizer (Rose Bengal) used for the production of singlet oxygen. Corrections in the results were made in the calculations of rates of quenching of singlet oxygen to allow for the triplet-state quenching. No extensive quenching of the singlet state of the dye was observed at the concentrations of the amines necessary for singlet-oxygen quenching. In one case (N, N, N', N'-tetramethylphenylenediamine) there was no observable chemical reaction between singlet oxygen and the amine. It was concluded that singlet oxygen undergoes physical quenching by the amines via partial charge-transfer intermediates.     

Best Approximation in an Asymmetrically Weighted L1 Measure

Let f(x) be a given, real-valued, continuous function definedon an interval [a,b]of the real line. Given a set of m real-valued,continuous functions _j(x) defined on [a,b], a linear approximatingfunction can be formed with any real setA = {a₁, a₂,..., a_m}. We present results for determining A sothat F(A, x) is a best approximation to(x) when the measureof goodness of approximation is a weighted sum of |F(A, x)–f(x)|,the weights being positive constants, w, when F(A, x) f(x)and w2 otherwise (when w, = w2 = 1, the measure is the L₁, norm).The results are derived from a linear programming formulationof the problem. In particular, we give a theorem which shows when such bestapproximations interpolate the function at fixed ordinates whichare independent of f(x). We show how the fixed points can becalculated and we present numerical results to indicate thatthe theorem is quite robust.     

Detecting dark energy in long baseline neutrino oscillations

In this paper, we discuss a possibility of studying properties of dark energy in long baseline neutrino oscillation experiments. We consider two types of models of neutrino dark energy. For one type of models the scalar field is taken to be quintessence-like and for the other phantom-like. In these models the scalar fields couple to the neutrinos to give rise to spatially varying neutrino masses. We will show that the two types of models predict different behaviors of the spatial variation of the neutrino masses inside the Earth and consequently result in different signals in long baseline neutrino oscillation experiments.     

Smoothing Data with Tolerances by Use of Linear Programming

This report describes a method for smoothing observed data whenthe values of the dependent variable are assumed to lie withinspecified tolerance of the observed value. Linear programmingis employed to obtain optimal smoothing of the (local) degreedesired within the restraints imposed by the tolerances. First-andthird-degree smoothing are discussed, but the method may beextended to higher order.     

磷通过热生长二氧化硅层在硅中的扩散

用四探针测量薄层电导方法及阳极氧化去层技术,测定了磷在硅中扩散的具体分布,在恒表面浓度下,它们偏离余误差函数分布。如认为这是由于扩散系数是杂质浓度的函数,实验得到了当杂质浓度大于10¹⁹原子/厘米³时,扩散系数随杂质浓度增加而增大的强烈依赖关系。用同样方法测定了磷通过二氧化硅层后在硅中扩散的具体分布,研究了这些杂质分布的特性,实验表明,不同厚度的氧化层在1300℃高温下仍具有掩蔽效应,在完全掩蔽失效时间附近,杂质分布的共同特点是表面浓度较低(～10¹⁷原子/厘米³)、结较浅(～1微米)。对不同厚度的氧化层,经过足够的时间后,硅中表面浓度不受氧化层厚度的影响,而只由扩散源的蒸气压决定。磷通过氧化层后扩散的具体分布情况还与扩散源的性质、条件等密切相关。扩散过程中观察到的氧化层厚度增长有可能影响表面附近杂质的具体分布情况。