We extend our previous formulation of low-energy QCD in terms of an effective lagrangean containing operators of dimensionality d ≤ 6 constructed with pseudoscalars and quark fields, describing physics below the scale of chiral symmetry breaking. We include in this paper the vector and axial-vector channels. We follow closely the Extended Chiral Quark Model approach and consistently work in the large-N c and leading log approximation and take into account the constraints from chiral symmetry and chiral symmetry restoration. The optimal fit of all parameters gives further support to a heavy scalar meson with a mass ∼ 1 GeV and a value of the axial pion-quark coupling constant g A 0.55 to 0.66, depending on some assumptions concerning the Weinberg sum rules.

We have previously proposed a method for depositing silicon dioxide films on Si from tetraethoxysilane Si(OC2H~)4 (TEOS) using ultraviolet (UV) light from a low pressure mercury lamp. In the method, an organic solution which contains TEOS is spin-coated onto a Si wafer surface to form a thin organic film which is then exposed to the UV light to synthesize silicon dioxide. The photochemical reactions responsible for the oxide formation and the thermal properties of deposited films have been investigated using infrared (IR) and UV absorption spectroscopy and thermal desorption spectroscopy (TDS). IR and UV absorption data confirm that the UV light decomposes organic compounds in the spin-coated organic film to conve~'t the film into a silicon dioxide film. We show that some photochemical reactions responsible for the decomposition of organic compounds are two-step processes. TDS data demonstrate that the deposited film is stable from substrate heating to approximately 400~

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The electrical conduction mechanism of composites below the percolation threshold has been generally discussed with the hopping conduction model. In this article, the electrical conduction mechanism of carbon black-polyethylene composites below the percolation threshold is discussed based on the frequency dependence of conductivity in the range of 20 Hz to 1 MHz. There are two components for observed ac loss current. One is independent of frequency and becomes prevalent in low frequencies just below the percolation threshold and under high electric field. The other is proportional to the frequency of applied ac voltage in high frequencies and its origin is not clear. These results support the conclusion that the electrical conduction mechanism below the percolation threshold is tunneling.

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