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In this novel, the iron(III)-PVC membrane sensor was investigated based on a new 1,1'-(iminobis(methan-1-yl-1-ylidene))dinaphthalen-2-ol (IBMYD) synthetic ionophore as a suitable carrier. The best performance was observed for the membrane composition including 33.0% PVC, 65.0% TEHP, 1.0% NaTPB and 1.0% ionophore. The electrode displayed a linear potential response over a wide concentration range from 1.0 x 10(-7) to 1.0 x 10(-1)mol L(-1), with a detection limit of 5.0 x 10(-8)mol L(-1) and a good Nernstian slope of 19.9+/-0.3 mV decade(-1). The sensor possessed some advantages such as short conditioning time, very fast response time (<12s) and especially good discriminating ability towards Fe(III) ions over a wide variety of alkali, alkaline earth, transition, and heavy metal ions. The potential response of the proposed sensor was independent of the pH of the test solution, in the pH working range from 3.0 to 6.3. The fabricated electrode was applied for at least 2 months, without any measurable divergence in the potential characteristics. The optimized sensor was used successfully for direct and indirect determination of free iron species in some different synthetic and real samples with satisfactory results.

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The cloud point extraction behavior of Sn(II) and Sn(IV) using alpha-polyoxometalate and mixed surfactants solution was investigated. The mixture of a nonionic surfactant (Triton X-100) and a cationic surfactant (CTAB) was utilized as a suitable micellar medium for preconcentration and extraction of tin complexes. Sn(II) in the presence of Sn(IV) was extracted with alpha-polyoxometalate, 0.3% (w/v) Triton X-100 and 3.5x10(-5) mol L(-1) CTAB at pH 1.2. Whereas the pH value of 3.7 were used for the individual determination of Sn(II) and Sn(IV) and also for total tin determination at the same conditions. Enrichment factors of 100 were obtained for the preconcentration of both metal ions. Under the optimal conditions, linearity was obeyed in the ranges of 55-670 microg L(-1) of Sn(II) and 46-750 microg L(-1) of Sn(IV) ion concentration. The detection limit of the method was also found to be 12.6 microg L(-1) for Sn(IV) and 8.4 microg L(-1) for Sn(II). The relative standard deviation of seven replicate determination of 100 microg L(-1) both metal ions were obtained about 2.4%. The diverse ion effect of some anions and cations on the extraction efficiency of target ions were tested. Finally, the optimized conditions developed were successfully utilized for the determination of each metal ion in various alloy, juice fruit, tape and waste water samples with satisfactory results.

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A novel potentiometric zirconium--PVC matrix membrane sensor incorporating bis(diphenylphosphino) ferrocene as an electroactive material and tris(2-ethylhexyl)phosphate as solvent mediator is described. In mixed acetate buffer solution of pH 4.8, the sensor displays a rapid and linear response for zirconium ion over the concentration range 1.0 x 10(-1) to 1.0 x 10(-7) mol L(-1) with a good slope of 59.7+/-0.3 mV per decade and detection limit 1.8 x 10(-8) mol L(-1). The best performance was obtained with membrane composition 33% PVC, 65% TEHP, 1% NaTPB and 1% ionophore. The proposed electrode revealed excellent selectivity for zirconium ion over a wide variety of alkali, alkaline earth, transition and heavy metal ions and could be used in a pH range of 4.15-7.8. The electrode was applied for at least 1 month without any considerable divergence in the potential responses. The practical utility of the electrode has been demonstrated by its use as an indicator electrode in the potentiometric titration of zirconium ions with sodium fluoride and in determination of zirconium ion in some alloy, tape and waste water samples.

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Special literature (surgical, forensic-medical and criminalistic) is reviewed on classification, mechanisms of a harmful action and characteristics of injuries inflicted by non-lethal arms. Some details of such arms construction and damaging action are given.

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The problem of studying injuries inflicted by different kinds of self-defense weapons is of great interest both to medical workers of different specialties (experts in forensic medicine, surgeons, toxicologists etc.) and to criminologists. Cases from practice of clinical and forensic medicine show that shots from pistols PB-4 with cartridges of traumatic action depending on the distance and the injured area as well as on other dynamic parameters of the interaction of the shell and the obstacle can cause injuries of different degrees of severity.

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A case of causing a lethal injury from the PB-4 self-defense pistol (traumatic action bullets) is described. An issue of the relation between notions "a non-lethal gun" and "special-purpose weapon" are under discussion.

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