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K Orzechowski

Publications and source records attributed to K Orzechowski.

4 recordsLinked to original sources
PubMed2005

Dielectric dispersion in water + 2-hydroxypyridine solid mixtures.

The complex electric permittivity was measured in water + 2-hydroxypyridine (2HP) solid mixtures as a function of concentration, temperature and frequency. Just after freezing of diluted mixtures, (mole fraction of 2HP < 0.2) pronounced dielectric dispersion in the MHz region was observed. The dispersion disappears on cooling between -30 and -40 degrees C in a first-order phase transition. The dispersion was explained in terms of the movement of a guest molecule (2HP) in a clathratelike structure of ice.

Journal Article↗
PubMed2002

Critical behavior in broad-band dielectric relaxation on approaching the critical consolute point in ethanol-dodecane mixture.

We present a quantitative experimental evidence for the influence of critical fluctuations on the high frequency dielectric relaxation in a binary critical mixture. The analysis clearly shows the presence of critical anomaly both for the maxima (epsilon(")(p)) and frequencies (f(p)) of loss curves peaks. For the temperature evolution of epsilon(")(p) similar relation as for the static dielectric permittivity was obtained. The temperature dependence of relaxation times can be portrayed by using the Eyring-type equation remote from the critical consolute point and shows the unusual precritical speeding up. The obtained behavior resembles that found recently in the isotropic phase of nematic liquid crystals [A. Drozd-Rzoska and S. J. Rzoska, Phys. Rev. E 65, 041701 (2002)]. Results presented agree also with the recent theoretical suggestion [S. Goodyear and S. C. Tucker, J. Chem. Phys. 111, 9673 (1999)] that relaxation in supercritical fluids may exhibit glasslike features.

Journal Article↗
PubMed1994

Simultaneous measurement of collagen type-VI-related antigen and procollagen type-III-N-propeptide levels in bronchoalveolar lavage.

Abnormal collagen metabolism is a hallmark of diffuse lung disease. Biochemical parameters which are correlated with collagen synthesis and degradation may be helpful to monitor fibrosis. In this study, we compared the sensitivity and specificity of procollagen type-III-N-propeptide (PIIINP) and collagen type-VI (C-VI) related antigen levels, as well as a ratio of both parameters (PIIINP/C-VI), in bronchoalveolar lavage fluid (BALF) from patients with diffuse and localized lung disease. We investigated 45 patients with diffuse lung disease (idiopathic pulmonary fibrosis (IPF), n = 21; sarcoidosis, n = 13; and lymphangitic carcinomatosis (LC), n = 11); 58 control subjects; and 92 patients with localized lung disease (bronchial carcinoma, n = 37; pulmonary tuberculosis, n = 31; and pneumonia, n = 24). C-VI and PIIINP were measured by immunoassay in concentrated BALF. Although the PIIINP and C-VI levels were increased in diffuse lung disease, the sensitivity of the individual parameters PIIINP and C-VI was low (IPF: PIIINP = 0.62, C-VI = 0.29; LC: PIIINP = 0.64, C-VI = 0.45; sarcoidosis: PIIINP = 0.69, C-VI = 0.15). When calculating the ratio of PIIINP/C-VI for each individual patient, we found a significant increase in this ratio in IPF (1.28 +/- 0.7), LC (2.34 +/- 1.2), and sarcoidosis (0.26 +/- 0.08) compared to both the controls (0.02 +/- 0.01) and other localized lung diseases (bronchial carcinoma 0.05 +/- 0.01; pulmonary tuberculosis 0.02 +/- 0.01), with the exception of pneumonia (0.18 +/- 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗