An-Najah National University

An-Najah Blogs


  • Monday, August 1, 2005
  • Critical behavior of the ultrasonic attenuation for the binary mixtures of benzene-coconut oil and hexane-beta, beta '-dichloroethyl ether
  • Published at:ACTA ACUSTICA UNITED WITH ACUSTICA Volume: 91 Issue: 4 Pages: 716-722 Published: JUL-AUG 2005
  • Ultrasonic absorption and velocity measurements were made as a function of temperature for the binary mixtures of benzene-coconut oil and hexane-beta, beta'-dichloroethyl ether. Ultrasonic absorption at 5, 7, 10, 15, 2 1, and 25 MHz and above T-c is a analyzed by the dynamic scaling theory of Ferrell and Bhattacharjee (FB). The ultrasonic absorption of the two binary mixtures exhibit strong temperature and frequency dependence near T-c. Ultrasonic velocity behaves as a linearly decreasing function of temperature above the critical temperature satisfying linear relation. The observed of alpha(c)/f(2) VS. f(-1.06) yields a straight line as predicted by FB theory. Experimental values of alpha/alpha(c), for the two binary critical mixtures are compared to the scaling function F(omega*).
  • Bookmark and Share Email
  • Wednesday, January 1, 2003
  • Effects of Noise Pollution on Blood Pressure, Heart Rate and Hearing Threshold in School Children
  • Published at:Pakistan Journal of Applied Science 3 (10-12): 717-723, 2003
  • This study reports the association of noise pollution level with blood pressure (systolic and diastolic), heart rate and hearing threshold in school children. The schools were selected randomly as to present quiet [Seida village, 68.2-71.1 dB(A)], noisy [Nablus city, 76.5-79.4 dB(A)] and very noisy, [Tulkarem refugees camp, 82.4-85.9 dB(A)] localities. Strong positive correlation (Pearson Correlation Coefficient ) were found between noise pollution level and systolic and diastolic blood pressure, heart rate and hearing threshold at different frequencies. The mean systolic and diastolic blood pressure for the two sexes are correlated positively with the noise pollution level (R = 0.521 and 0.440, respectively). The hearing threshold levels of different frequencies correlated positively with the noise pollution level ( R = 0.114 to 0.267; where p c 0.05).
  • Bookmark and Share Email
  • Wednesday, January 1, 2003
  • Two-Scale-Factor Universality of Binary Liquid Critical Mixtures
  • Published at:Not Found
  • The universal quantity of some binary liquid mixtures has been calculated, using the results of recent experimental collateral data. The values of for the systems are in good agreement with the other experimental and also with the theoretical values. The obtained average value of = 0.2691± 0.0028 supports the theoretical value of = v[n/4π]1/d,in three dimensions for n = 1 and d = 3 which indicates that fluid and binary mixtures transition belong to the same class of universality \"two-scale-factor universality\".
    Pakistan Journal of Applied Sciences 3(2): 142-144, 2003
  • Bookmark and Share Email
  • Wednesday, January 1, 2003
  • Noise pollution in factories in Nablus City
  • Published at:ACTA ACUSTICA UNITED WITH ACUSTICA Volume: 89 Issue: 5 Pages: 913-916 Published: SEP-OCT 2003
  • Noise pollution is becoming more and more important, especially in the industrialized and developed countries. Industrial noise is a serious environmental problem, which causes annoyance and disruption to daily activities. In the West Bank, however, there are so far no regulatory laws to limit high industrial noise levels. Due to a general lack of awareness about the ill effects of high noise levels, the owners of factories pay little attention to safety measures for their workers.
    Accordingly, this study is concerned with measuring the equivalent noise levels L-eq in 38 factories in Nablus city and comparison with international standards of noise. The obtained mean value of these levels is 85.5 dB(A). It has been found that the L-eq values for 40% of the selected factories are higher than the widely-adopted international standards. These factories are considered by the workers to be noisy sources. The continuous exposure of the workers to such high noise levels can cause hearing damage, speech masking
  • Bookmark and Share Email
  • Tuesday, January 1, 2002
  • Concentration and Temperature Dependence of Shear Viscosity of the Critical Mixture of Nitroethane and 3-Methylpentane
  • Published at:Not Found
  • Shear viscosity coefficients of nitroethane and 3-methylpentane mixture have been measured using digital viscometer. The measured values were over the entire concentration range above the critical temperature (Tc = 299.590 K) in the range 0.040 ? T- Tc ? 18.570 K. The results above the critical temperature Tc were analyzed by the mode coupling theory. The anomaly of shear viscosity was detected as a function of temperature and concentration. A least square fit near the critical temperature yields a value of noncritical part of shear viscosity ?0 = 0.358 cP. The Debye momentum cutoff qD and the constant A in the mode coupling approach were determined. Our values of ?0 and A are in good agreement with the literature values.
    An-Najah University Journal for Research - Natural Sciences (A) ISSN: 1727-2114
    Volume 16 , Issue 2 , 2002, Pages: 117-124
  • Bookmark and Share Email


Issam Rashidd
Show Full ProfileEnglish CV


Please do not email me if you do not know me
Please do not e-mail me if you do not know me