13 research outputs found
Kožna dekontaminacija živÄanoga bojnog otrova sarina s apsorpcijskim pripravkom u uvjetima in vivo
Our Instituteās nuclear, biological, and chemical defense research team continuously investigates and develops preparations for skin decontamination against nerve agents. In this in vivo study, we evaluated skin decontamination efficacy against sarin by a synthetic preparation called Mineral Cationic Carrier (MCCĀ®) with known ion exchange, absorption efficacy and bioactive potential. Mice were treated with increasing doses of sarin applied on their skin, and MCCĀ® was administered immediately after contamination. The results showed that decontamination with MCCĀ® could achieve therapeutic efficacy corresponding to 3 x LD50 of percutaneous sarin and call for further research.IstraživaÄki tim NBKO (nuklearno-bioloÅ”ko-kemijske obrane) radi na pronalasku i razvoju pripravka za dekontaminaciju kože od živÄanih bojnih otrova. Cilj ovog istraživanja bio je ispitati dekontaminacijska svojstva (adsorpcijska i/ili kemisorpcijska) pripravka MCCĀ® rabeÄi živÄani bojni otrov sarin kao kožni kontaminant u uvjetima in vivo. MCCĀ® je sintetski pripravak koji je biokemijski aktivan i ima ionskoizmjenjivaÄka i adsorpcijska svojstva. Istraživanje u uvjetima in vivo napravljeno je na miÅ”evima aplikacijom rastuÄih doza sarina na kožu životinje. Pripravak MCCĀ® uporabljen je kao kožni dekontaminant neposredno nakon kožne kontaminacije sarinom. Istraživanja su pokazala da pripravak MCCĀ® posjeduje adsorpcijska svojstva, ujedno važna za dekontaminaciju živÄanih bojnih otrova. Eksperimenti u uvjetima in vivo na miÅ”evima (NOD-soj) pokazali su da se dekontaminacijom pripravkom MCCĀ® može postiÄi terapijski uÄinak od 3 LD50 (perkutano, sarin)
Toxicological Effects of Weapons of Mass Destruction and Noxious Agents in Modern Warfare and Terorrism
Oružja za masovno uniÅ”tavanje najbolji su primjer uporabe civilizacijskih tehnoloÅ”kih dostignuÄa u Å”tetne svrhe i protiv ljudske civilizacije. UnatoÄ nastojanjima oko kontrole i smanjenja njihove koliÄine, rizik zbog samoga postojanja pa Äak i Å”irenja zahtijeva da se o njihovoj uporabi i dalje vodi raÄuna i da se poveÄaju obrambene mjere ā nuklearno-bioloÅ”ko-kemijske obrane (NBKO).
Osim suvremenog vojnika koji je u vojnim i mirovnim operacijama diljem svijeta izložen raznim noksama kemijskog, bioloÅ”kog i radioloÅ”kog podrijetla, nezaÅ”tiÄeno i uglavnom slabo educirano civilno stanovniÅ”tvo može biti izloženo teroristiÄkim napadima.
Oružja za masovno uniÅ”tavanje i nokse kemijskog, bioloÅ”kog i radioloÅ”kog podrijetla uzrokuju razne toksikoloÅ”ke posljedice, a bez obzira na njihovo podrijetlo, imaju zajedniÄki nazivnik djelovanja ā poremeÄaj fi zioloÅ”kog stanja u organizmu. PoremeÄaji proizaÅ”li nakon izlaganja tim noksama nerijetko se teÅ”ko determiniraju, dijagnosticiraju i lijeÄe.
U ovome su radu s biomedicinskog aspekta obraÄene važnije nokse kemijskog, bioloÅ”kog i radioloÅ”kog podrijetla na temelju odabranih primjera iz terorizma i suvremenog ratovanja: polonij-210, osiromaÅ”eni uran, salmonela, bedrenica (antraks), genetiÄki modifi cirane bakterije, polimerno predivo āpauÄinaā i bojni otrovi sarin i iperit.Weapons of mass destruction (WMD) best portray the twisted use of technological achievements against the human species. Despite arm control efforts, WMD threat continues to exist and even proliferate. This in turn calls for improvement in defensive measures against this threat. The modern soldier is exposed to a number of chemical, biological, and radiological agents in military and peace operations, while civilians are mainly exposed to terrorist attacks. Regardless of origin or mode of action, WMDs and other noxious agents aim for the same ā to make an organism dysfunctional. Because their effects are often delayed, these agents are hard to spot on time and treat.
This review presents a biomedical aspect of agents used in warfare and terrorism, including polonium-210, depleted uranium, salmonella, anthrax, genetically modifi ed bacteria, cobweb-like polymer fi bre, sarin, and mustard gas
Anisotropic molecular diffusion in confinement II: A model for structurally complex particles applied to transport in thin ionic liquid films
Hypothesis:Diffusion in confinement is an important fundamental problem with
significant implications for applications of supported liquid phases. However,
resolving the spatially dependent diffusion coefficient, parallel and
perpendicular to interfaces, has been a standing issue and for objects of
nanometric size, which structurally fluctuate on a similar time scale as they
diffuse, no methodology has been established so far. We hypothesise that the
complex, coupled dynamics can be captured and analysed by using a model built
on the -dimensional Smoluchowski equation and systematic coarse-graining.
Methods and simulations: For large, flexible species, a universal approach is
offered that does not make any assumptions about the separation of time scales
between translation and other degrees of freedom. The method is validated on
Molecular Dynamics simulations of bulk systems of a family of ionic liquids
with increasing cation sizes where internal degrees of freedom have little to
major effects.
Findings: After validation on bulk liquids, where we provide an
interpretation of two diffusion constants for each species found
experimentally, we clearly demonstrate the anisotropic nature of diffusion
coefficients at interfaces. Spatial variations in the diffusivities relate to
interface-induced structuring of the ionic liquids. Notably, the length scales
in strongly confined ionic liquids vary consistently but differently at the
solid-liquid and liquid-vapour interfaces.Comment: 21 pages, 14 figures, 5 tables, pdflatex, submitted to JCIS; This is
a follow-up to "Anisotropic molecular diffusion in confinement I: Transport
of small particles in potential and density gradients" due to a split of
arXiv:archive/2212.0954
Mechanism of the Water-Gas Shift Reaction Catalyzed by Efficient Ruthenium-Based Catalysts: A Computational and Experimental Study
Supported ionic liquid phase (SILP) catalysis enables a highly efficient, Ruābased, homogeneously catalyzed waterāgas shift reaction (WGSR) between 100āĀ°C and 150āĀ°C. The active Ruācomplexes have been found to exist in imidazolium chloride melts under operating conditions in a dynamic equilibrium, which is dominated by the [Ru(CO)3Cl3]ā complex. Herein we present stateāofātheāart theoretical calculations to elucidate the reaction mechanism in more detail. We show that the mechanism includes the intermediate formation and degradation of hydrogen chloride, which effectively reduces the high barrier for the formation of the requisite dihydrogen complex. The hypothesis that the rateālimiting step involves water is supported by using D2O in continuous catalytic WGSR experiments. The resulting mechanism constitutes a highly competitive alternative to earlier reported generic routes involving nucleophilic addition of hydroxide in the gas phase and in solution
Insights from molecular dynamics simulations on structural organization and diffusive dynamics of an ionic liquid at solid and vacuum interfaces
HypothesisA reliable modelling approach is required for simultaneous characterisation of static and dynamic properties of bulk and interfacial ionic liquids (ILs). This is a prerequisite for a successful investigation of experimentally inaccessible, yet important properties, including those that change significantly with the distance from both vacuum and solid interfaces.SimulationsWe perform molecular dynamics simulations of bulk [C2Mim][NTf2], and thick IL films in contact with vacuum and hydroxylated sapphire surface, using the charge methods CHelpG, RESP-HF and RESP-B3LYP with charge scaling factors 1.0, 0.9 and 0.85.FindingsBy determining and employing appropriate system sizes and simulations lengths, and by benchmarking against self-diffusion coefficients, surface tension, X-ray reflectivity, and structural data, we identify RESP-HF/0.9 as the best non-polarizable force field for this IL. We use this optimal parametrisation to predict novel physical properties of confined IL films. First we fully characterise the internal configurations and orientations of IL molecules relative to, and as a function of the distance from the solid and vacuum interfaces. Second, we evaluate densities together with mobilities in-plane and normal to the interfaces and find that strong correlations between the ILās stratification and diffusive transport in the interfacial layers persist for several nanometres deep into IL films
Structural characterization of an ionic liquid in bulk and in nano-confined environment using data from MD simulations
\u3cp\u3eThis article contains data on structural characterization of the [C2Mim][NTf2] in bulk and in nano-confined environment obtained using MD simulations. These data supplement those presented in the paper āInsights from Molecular Dynamics Simulations on Structural Organization and Diffusive Dynamics of an Ionic Liquid at Solid and Vacuum Interfacesā [1], where force fields with three different charge methods and three charge scaling factors were used for the analysis of the IL in the bulk, at the interface with the vacuum and the IL film in the contact with a hydroxylated alumina surface. Here, we present details on the construction of the model systems in an extended detailed methods section. Furthermore, for best parametrization, structural and dynamic properties of IL in different environment are studied with certain features presented herein.\u3c/p\u3
Insights from molecular dynamics simulations on structural organization and diffusive dynamics of an ionic liquid at solid and vacuum interfaces
Hypothesis: A reliable modelling approach is required for simultaneous characterisation of static and dynamic properties of bulk and interfacial ionic liquids (ILs). This is a prerequisite for a successful investigation of experimentally inaccessible, yet important properties, including those that change significantly with the distance from both vacuum and solid interfaces. Simulations: We perform molecular dynamics simulations of bulk [C2Mim][NTf2], and thick IL films in contact with vacuum and hydroxylated sapphire surface, using the charge methods CHelpG, RESP-HF and RESP-B3LYP with charge scaling factors 1.0, 0.9 and 0.85. Findings: By determining and employing appropriate system sizes and simulations lengths, and by benchmarking against self-diffusion coefficients, surface tension, X-ray reflectivity, and structural data, we identify RESP-HF/0.9 as the best non-polarizable force field for this IL. We use this optimal parametrisation to predict novel physical properties of confined IL films. First we fully characterise the internal configurations and orientations of IL molecules relative to, and as a function of the distance from the solid and vacuum interfaces. Second, we evaluate densities together with mobilities in-plane and normal to the interfaces and find that strong correlations between the IL's stratification and diffusive transport in the interfacial layers persist for several nanometres deep into IL films