In this paper, the authors continue their work on the problem of nding an h = h(x) as small as possible such that for x su ciently large, there is a squarefree number in the interval (x; x + h]: This problem has been investigated by Fogels [4], Roth [11], Richert [10], Rankin [9], Schmidt [12], Graham and Kolesnik [5], the second author [14,15], and the rst author [2]. In particular, the author...

the reaction between ni(ii), co(ii), cr(iii) bitrates, ni(ii) chloride and ambidentate a-keto ylide benzoylmethylenetriphenylphosphine (bppy) resulted in isolation of [ni(bppy)2](no3)2.2h2o, [ni(bppy)2]cl2, [co(bppy)2](no3)2 and [cr(bppy)3](no3)3; 2h2o. the compounds were characterized by elemental analyses and infrared 1hnmr spectroscopy, molar conductivity in solution and molecular weight mea...

heavy metals such as cu(ii) and pb(ii) are among the hazardous pollutants that lead to severe ecological problems and have a toxic effect on living organisms. the removal of cu(ii) and pb(ii) by iranian bentonite experiment were conducted in single component and multi component systems. the bentonite from the birjand area was characterized by x-ray diffraction pattern and ftir spectroscopy. the...

The complexation reactions between N,N'-3,6-dioxa-1,8-octanebis (salicylaldimine) [saldioxen(I)] and Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) were studied spectrophotometrically in methanol solution at 25 °C. The stoichiometry of the complexes were obtained as 2:1 and 1:1 sadioxen-metal ion using mole ratio method. The formation constants of the complexes were determined, a...

purpose: to compare orbscan ii and ultrasonic pachymetry for measurement of central corneal thick-ness (cct) in eyes scheduled for keratorefractive surgery. methods: cct was measured using orbscan ii and then by ultrasonic pachymetry in 100 eyes of 100 patients who were scheduled for excimer laser refractive surgery. paired t-test was used for comparing the results. results: using an acoustic f...

Abstract Intestinal duplication cysts are rare disease entirety, most commonly presenting in childhood. The incidence is 1:4,500 births, with a slight male predominance. They can occur anywhere along the alimentary tract, 35% ileum and 10% jejunum. Diagnosis prove challenging as they present vast variation of symptoms mimic other pathologies. A 29-year-old presented to A&E following collaps...