1-(2-Pyridylazo)-2-naphthol (PAN) has been used for the simultaneous and individual determination of palladium and cobalt at trace levels. PAN complexes of palladium and cobalt at neutral pH form green-color neutral complexes, which are soluble in aqueous SDS micellar media. Under optimum conditions, calibration graphs for individual determinations by zero and first-derivative spectrophotometry...

vanadium is quantitatively retained on 2-nitroso-1-naphhthol-4-sulfonic acid tetradecyldimethlbenzyammonium chloride onto microcrystalline naphthalene in the ph range of 3.0-4.0 from a large volume of aqueous solutions of various alloys and synthetic samples. after filtration, the solid mass consisting of the vanadium complex and naphthalene was dissolved with 5.0 ml of dimethylformamide and th...

Three methods are presented for simultaneous determination of ibuprofen and paracetamol without previous separation. The first method depends on first derivative UV spectrophotometry, with zero-crossing measurement. The first derivative amplitudes at 230 and 290 nm were selected for the assay of ibuprofen and paracetamol, respectively. The second method depends on first derivative of the ratio-...

Gould and Robinson (NAR 08/18, Oxford University Computing Laboratory, 2008) gave global convergence results for a second-derivative SQP method for minimizing the exact l1-merit function for a fixed value of the penalty parameter. To establish this result, we used the properties of the so-called Cauchy step, which was itself computed from the so-called predictor step. In addition, we allowed fo...

Orthogonal decompositions (OD:s) that are monomial have been constructed for most simple Lie algebras but in some cases the existence of an OD is still an open question. One of them is Lie algebras of type Cn where n is not a power of 2. In this paper we use computational methods to prove that C3 has no monomial OD. 1 Orthogonal decompositions of simple Lie algebras The basic question, of which...

Laser-induced fluorescence in rat tissue was studied during the uptake and clearing period of i.v.-injected hematoporphyrin derivative. A malignant rat tumor and normal tissue of 20 different kinds from the tumor-bearing animals were investigated. A pulsed nitrogen laser (337 nm) was used in conjunction with an optical multichannel analyzer system, in which the whole fluorescence light distribu...

This article develops a method of ratio estimate in fuzzy sense. By both the simple random sampling and stratified random sampling, we can obtain the ratio estimate in usual statistical sense. However, the sampling data may be ambiguous in some uncertain circumstance. To solve such kind of problem, we probe into the simple random sampling and stratified random sampling in fuzzy sense, obtain th...

In [19], we gave global convergence results for a second-derivative SQP method for minimizing the exact l1-merit function for a fixed value of the penalty parameter. To establish this result, we used the properties of the so-called Cauchy step, which was itself computed from the so-called predictor step. In addition, we allowed for the computation of a variety of (optional) SQP steps that were ...

Sequential quadratic programming (SQP) methods form a class of highly efficient algorithms for solving nonlinearly constrained optimization problems. Although second derivative information may often be calculated, there is little practical theory that justifies exact-Hessian SQP methods. In particular, the resulting quadratic programming (QP) subproblems are often nonconvex, and thus finding th...

Sequential quadratic programming (SQP) methods form a class of highly efficient algorithms for solving nonlinearly constrained optimization problems. Although second derivative information may often be calculated, there is little practical theory that justifies exact-Hessian SQP methods. In particular, the resulting quadratic programming (QP) subproblems are often nonconvex, and thus finding th...