Nitrogen-enriched activated carbons were prepared from a Polish brown coal. Nitrogen was introduced from urea at 350 °C in an oxidizing atmosphere both to carbonizates obtained at 500-700 °C and to activated carbons prepared from them. The activation was performed at 800 °C with KOH in argon. It has been observed that the carbonization temperature determines the amount of nitrogen that is incorporated (DC5U, 8.4 wt % N daf ; DC6U, 6.3 wt % N daf ; and DC7U, 5.4 wt % N daf ). X-ray photoelectron spectroscopy (XPS) measurements have shown that nitrogen introduced both at the stage of carbonizates and at the stage of activated carbons occurs mainly as N-6, N-5, and imine, amine and amide groups. On the other hand, the activation of carbons enriched with nitrogen results in the formation of pyridonic nitrogen and N-Q. The introduction of nitrogen at the activated carbon stage leads to a slight decrease in surface area. It has been proven that the most effective way of preparing microporous activated carbons enriched with nitrogen to a considerable extent and having high surface area (∼3000 m 2 /g) is the following: carbonization f activation f reaction with urea.

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The study reported has been undertaken to characterize the changes taking place on the surface of the nitrogen-enriched active carbons. The method applied for this purpose was X-ray photoelectron spectroscopy (XPS), and the samples studied were active carbons prepared from Polish brown and bituminous coals. An ammonia-air mixture was applied as a reagent introducing nitrogen functions into the carbon structure. Nitrogen was introduced both to demineralized coals and to active carbons obtained by carbonization and chemical activation of nonmodified precursors. The activation was performed at 700 °C with KOH, in an argon atmosphere. Results of XPS measurements have shown that in the active carbons enriched in nitrogen at the stage of precursor the dominant nitrogen species are the N-5 and N-6 groups; while in the samples ammoxidized after chemical activation, the dominant nitrogen species are the surface groups of imines, amines, amides and nitriles, accompanied by lactams and N-5 and N-6 groups.

The paper presents results of a study on obtaining activated carbon from common corn cobs and on its use as adsorbent for removal of pollution from liquid and gas phases. The crushed precursor was subjected to pyrolysis at 500 and 800°C in argon atmosphere and next to physical or chemical activation by CO 2 and KOH respectively. The effect of pyrolysis conditions and activation method on the physicochemical properties of the materials obtained was tested. The sorption properties of the carbonaceous adsorbents obtained were characterized by determination of nitrogen dioxide and hydrogen sulphide sorption from gas stream in dry and wet conditions as well as by iodine and methylene blue removal from aqueous solution.The final products were microporous activated carbons of well-developed surface area varying from 337 to 1213 m 2 /g and showing diverse acid-base character of the surface. The results obtained in our study have proved that a suitable choice of the activation procedure for corn cobs permits production of cheap adsorbents with high sorption capacity toward toxic gases of acidic character as well as different pollutants from liquid phase.

This article shows that nanodiamonds can transmigrate through the insect cuticle easily, and the doses used were not hemocytotoxic and did not cause inhibition of cellular and humoral immune responses in larvae, pupae and adults of Tenebrio molitor . The examination of the nanodiamond biodistribution in insect cells demonstrated the presence of nanodiamond aggregates mainly in hemocytes, where nanoparticles were efficiently collected as a result of phagocytosis. To a lesser extent, nanodiamond aggregates were also detected in fat body cells, while they were not observed in Malpighian tubule cells. We functionalized nanodiamonds with Neb -colloostatin, an insect hemocytotoxic and gonadoinhibitory peptide, and we showed that this conjugate passed through the insect cuticle into the hemolymph, where the peptide complexed with the nanodiamonds induced apoptosis of hemocytes, significantly decreased the number of hemocytes circulating in the hemolymph and inhibited cellular and humoral immune responses in all developmental stages of insects. The results indicate that it is possible to introduce a peptide that interferes with the immunity and reproduction of insects to the interior of the insect body by means of a nanocarrier. In the future, the results of these studies may contribute to the development of new pest control agents.

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Nitrogen-enriched active carbon has been obtained from Polish brown coal from the "Konin" colliery. The process of ammoxidation by a mixture of ammonia and air at the ratio of 1:3 has been performed at two temperatures (300 and 350 °C) at different stages of the production, that is, at that of precursor, char, and active carbon. It has been shown that the stage at which the process of ammoxidation is conducted has profound effect on the amount of nitrogen introduced into the carbon structure. The carbonization and activation (by steam or KOH) of nitrogen-enriched samples leads to significant reduction of the nitrogen content. The final products were microporous active carbons of well-developed surface area varying from 604 to 3181 m 2 /g and having nitrogen content from 0.4 to 6.5 wt%, showing different acid-base character of the surface.