Ubrzo nakon uvođenja komercijalnih automatskih detektora bojnih otrova, većinom temeljenih na spektrometriji ionske pokretljivosti, krajem 20. stoljeća razvijaju se terenski uređaji koji primjenjuju ...i druge tehnike kemijske detekcije (FTIR, Raman, GC-MS, površinski akustični val, fotoakustične, elektrokemijske, biosenzorske i ostale). Od navedenih tehnika, prijenosni GC-MS detektori omogućuju vrlo pouzdanu kvalitativnu i kvantitativnu kemijsku analizu, no problem predstavljaju visoka cijena tih uređaja, zahtjevnost u rukovanju s njima te kompleksna priprema uzoraka. Neke tehnike kemijske detekcije nisu primjenjive za razvoj pouzdanog ručnog kemijskog detektora, a niti jedna tehnika, zasad, ne omogućuje razvoj univerzalnog kemijskog detektora. Potencijalno rješenje je razvoj višestrukog senzorskog uređaja koji bi kompenzirao negativne strane svakog od senzora. U ovom radu dan je pregled komercijalno dostupnih kemijskih detektora temeljenih na novim generacijama tehnika detekcije te pregled znanstvenih istraživanja usmjerenih na daljnji razvoj detekcije bojnih otrova s jednostavnijim, pouzdanijim i poželjno jeftinijim rješenjima.
Detekcija bojnih otrova i toksičnih industrijskih kemikalija iznimno je važna za sigurnosne snage. Dugo se zasnivala na kolorimetrijskoj kemiji, a tek je razvoj elektronike omogućio automatizaciju i ...minijaturizaciju kemijske detekcije. Krajem 20. stoljeća na tržište su počeli dolaziti automatski kemijski detektori koji su se većinom temeljili na spektrometriji ionske pokretljivosti (IMS). Danas se kolorimetrijski detektori ponovno sve više upotrebljavaju zbog odlične selektivnosti i niske cijene te se razvijaju novi kromogeni reagensi. S druge strane razvoj IMS detektora fokusiran je na primjenu asimetričnog polja s obzirom na to da ono omogućava male dimenzije i veću osjetljivost detektora. U ovom radu, uz komercijalno dostupne kemijske detektore bazirane na tehnikama kolorimetrije i spektrometrije ionske pokretljivosti, dan je pregled znanstvenih istraživanja usmjerenih na daljnji razvoj tih tehnologija detekcije s ciljem povećanja selektivnosti i osjetljivosti.
The novel N‐1‐sulfonylcytosine‐cyclam conjugates 1 and 2 conjugates are ionized by electrospray ionization mass spectrometry (ESI MS) in positive and negative modes (ES+ and ES−) as singly ...protonated/deprotonated species or as singly or doubly charged metal complexes. Their structure and fragmentation behavior is examined by collision induced experiments. It was observed that the structure of the conjugate dictated the mode of the ionization: 1 was analyzed in ES− mode while 2 in positive mode. Complexation with metal ions did not have the influence on the ionization mode. Zn2+ and Cu2+ complexes with ligand 1 followed the similar fragmentation pattern in negative ionization mode.
The transformation from 2°‐amine in 1 to 3°‐amine of cyclam ring in 2 leads to the different fragmentation patterns due to the modification of the protonation priority which changed the fragmentation channels within the conjugate itself. Cu2+ ions formed complexes practically immediately, and the priority had the cyclam portion of the ligand 2. The structure of the formed Zn2+ complexes with ligand 2 depended on the number of 3° amines within the cyclam portion of the conjugate and the ratio of the metal:ligand used. The cleavage of the cyclam ring of metal complexes is driven by the formation of the fragment that suited the coordinating demand of the metal ions and the collision energy applied. Finally, it was shown that the structure of the cyclam conjugate dictates the fragmentation reactions and not the metal ions.
Pod pokroviteljstvom Vlade Republike Hrvatske održan je od 2. do 6. rujna 2018. godine Deseti svjetski kongres o kemijskoj, biološkoj, radiološkoj i nuklearnoj (KBRN) znanosti i nadzoru posljedica u ...„Hotelu Croatia” u Cavtatu. U sklopu kongresa od 3. do 4. rujna 2018. godine provedena je radionica pod nazivom „Stanje sustava nuklearne, radiološke, kemijske i biološke obrane u sustavu domovinske sigurnosti Republike Hrvatske” na kojoj su sudjelovali i predstavnici ustrojstvenih jedinica MORH-a i OSRH-a (roda NBKO i zdravstvene službe).
The „Convention on the prohibition of military or any other hostile use of environmental modification technique“ (referred lately in this paper as “Convention”), effective since 5 October 1978, ...strictly forbade military usage of Environmental Modification Techniques (ENMOD). The Convention protects signatory nations more broadly; against any other hostile use of the ENMOD technologies, and to advocate cooperation, trust and scientific knowledge exchange between the signatory nations. The Convention also offers UN role in consultation, protection and the determined protocol for a possible issue caused by the application of the ENMOD technologies. Since the dissolution of Yugoslavia, in the early nineties, only one country; the Republic of Slovenia, ratified the Convention. Due to this fact, a large area in Southeast Europe has no proper international regulation of this matter. Regardless of the minor possibility of military ENMOD application in the region, there is an increasing expectancy of unilateral ENMOD applications as a response to economic losses caused by climate change (impacts on hydrology cycle, agriculture, forestry etc.). The main goal of this work is to apply an objective multi-criterion decision analyse, in the form of combined Analytic Hierarchy Process and Analytic Network Process, to suggest a course of action for decision-makers in the ENMOD regulation. Besides ranked alternatives, many latent and side suggestions arose from the results helping to determine the next best alternative in the case of inability to realize the best option: assembling a regional summit to promote Convention ratification.
We report about the selective reduction of eight cyclohexanones with NaBH
4
in aqueous solutions of β-cyclodextrin, PEG-400, cationic micelles of CTAB and CPC, anionic micelles of SDS and SS at room ...temperature and at 80°C. All results were compared with NMR, GC-MS as well as with IR. The charge of the micellar head group influences the preferential direction of hydride attack by favoring one reactant conformation over the other and the outcome is more products with the H
−
in the axial position. One example is the reduction of ketone 4. It was obtained 73% of trans 4-tert-butylcyclohexanol in CTAB, 90% in SDS and 94% in SS micelles. The importance of this work is in the obtained selectivity, the high yields, and the simplicity.
U ovom doktorskom radu sintetizirani su Cu(II) molekulski kompleksi Cu(1-TsC-N3)2Cl2 i Cu(1-MsC-N3)2Cl2 biološki aktivnih N-sulfonilcitozinskih (C) liganada s tosilom (Ts) i mezilom (Ms) te novi ...ciklam-TsC konjugati. Mannichova reakcija TsC liganda, paraformaldehida i ciklama u prisutnosti octene kiseline daje C-aminometilirani konjugat u kojem je ciklam vezan preko metilenskog mosta na C5 položaj citozina. Ista reakcija sa zaštićenim ciklamom daje C4 aminometilirani produkt. Pomoću ESI-MS metode provedena je studija stabilnosti i utjecaja biološki važnih metalnih iona (Na+, K+, Ca2+, Mg2+, Zn2+, Cu2+) na ligande, Cu(II) komplekse, te na poliaza makrocikličke konjugate. U interakciji s ligandima i Cu(II) kompleksima alkalijski metali uslijed elektrostatskih interakcija stvaraju klastere, dok je nastanak bis i tris te miješanih kompleksa uočen u interakciji s Ca2+ i Mg2+. Interakcija Zn2+ s ligandima i Cu(II) kompleksima rezultira nastankom monometalnih kompleksa kao i dimetalnih kompleksa zbog afniteta Zn2+ prema atomima kisika i dušika koji u strukturu uključuju molekule vode. Novi poliaza makrociklički konjugati u interakciji s CuCl2 stvaraju molekulske komplekse u kojima je CuCl2 u ciklamskom prstenu, a u interakciji s ZnSO4 nastaju ionski kompleksi u kojima je Zn2+ smješten u ciklamskom prstenu.
Abstract In this doctoral thesis, Cu (II) molecular complexes Cu(1-TsC-N3)2Cl2 and Cu(1-MsC-N3)2Cl2 of biologically active N-sulfonylcytosine ligands (C) with tosyl (Ts) and mesyl (Ms) and new cyclame-TsC conjugates were synthesized. The Mannich reaction of TsC, paraformaldehyde and cyclame in the presence of acetic acid yields C-aminomethylated konjugate in which the cyclame was introduced through a methylene bridge at C5 position of cytosine. The same reaction with protected cyclame gives C4 aminomethylated product. Using ESI-MS method was conducted stability studies and the influence of biologically important metal ions (Na+, K+, Ca2+, Mg2+, Zn2+, Cu2+) to ligands, Cu (II) complexes, and polyaza macrocyclic conjugates. The interaction of ligands and Cu (II) complexes with biologically important metal ions results with formation of various metal complex. Alkali metals Na+ and K+ formed clusters due to the electrostatic inetractions. Bis, tris and mixed ligand complexes were observed upon mixing with Ca2+ or Mg2+ salt. Interaction with Zn2+ sieed monometal Zn2+ complexes and mixed ligand dimetal complexes that includ water molecules in the structures of the complexes because of affinity of Zn2+ for both O and N atoms. Both ions Cu2+ and Zn2+ were located within the cyclamic ring upon their interaction with polyaza macrocyclic conjugates. Newly formed Cu2+complexes were molecular while the ionic complexes were formed with zinc ions.
The „Convention on the prohibition of military or any other hostile use of environmental modification technique“ (referred lately in this paper as “Convention”), effective since 5 October 1978, ...strictly forbade military usage of Environmental Modification Techniques (ENMOD). The Convention protects signatory nations more broadly; against any other hostile use of the ENMOD technologies, and to advocate cooperation, trust and scientific knowledge exchange between the signatory nations. The Convention also offers UN role in consultation, protection and the determined protocol for a possible issue caused by the application of the ENMOD technologies. Since the dissolution of Yugoslavia, in the early nineties, only one country; the Republic of Slovenia, ratified the Convention. Due to this fact, a large area in Southeast Europe has no proper international regulation of this matter. Regardless of the minor possibility of military ENMOD application in the region, there is an increasing expectancy of unilateral ENMOD applications as a response to economic losses caused by climate change (impacts on hydrology cycle, agriculture, forestry etc.). The main goal of this work is to apply an objective multi-criterion decision analyse, in the form of combined Analytic Hierarchy Process and Analytic Network Process, to suggest a course of action for decision-makers in the ENMOD regulation. Besides ranked alternatives, many latent and side suggestions arose from the results helping to determine the next best alternative in the case of inability to realize the best option: assembling a regional summit to promote Convention ratification.
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