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Adsorption equilibria and NMR experiments were performed to study the adsorption and interactions of ammonia with metal-organic framework HKUST-1, or Cu3(BTC)2 (BTC ) 1,3,5-benzenetricarboxylate). Ammonia capacities determined from chemical breakthrough measurements show significantly higher uptake capacities than from adsorption alone, suggesting a stronger interaction involving a potential reaction with the Cu3(BTC)2 framework. Indeed, 1H MAS NMR reveals that a major disruption of the relatively simple spectrum of Cu3(BTC)2 occurs to generate a composite spectrum consistent with Cu(OH)2 and (NH4)3BTC species under humid conditions--the anticipated products of a copper(II) carboxylate reacted with limited ammonia. These species are not detected under dry conditions; however, reaction stoichiometry combined with XRD results suggests the partial formation of an indeterminate diammine copper(II) complex with some residual Cu3(BTC)2 structure retained. Cu(II)-induced paramagnetic shifts exhibited by various species in 1H and 13C MAS NMR spectra are consistent with model compounds and previous literature. Although results show extensive ammonia capacity of Cu3(BTC)2, much of the capacity is due to reaction with the structure itself, causing a permanent loss in porosity and structural integrity., Published in The Journal of Physical Chemistry C, v113 n31 p13906-13917, 2009. The original document contains color images.

Current technology-based efforts are focusing on a nanotechnology approach to sorbent development for air purification applications. Metal-organic frameworks (MOFs) and zeolitic imidazolate frameworks (ZIFs) are two novel classes of materials that allow for specific functionalities to be designed directly into a porous framework. This report is the second in a series of summary reports based on the evaluation of samples from the University of California, Los Angeles. The samples evaluated in this report are a continuation of a baseline series of materials aimed at collecting design rules for future materials; results from this and the previous report will be used to create a second-generation of reactive MOFs and ZIFs for air purification applications. Testing of the novel materials included nitrogen isotherm data, water, and chloroethane adsorption equilibria, and ammonia, cyanogen chloride and sulfur dioxide breakthrough data., The original document contains color images. All DTIC reproductions will be in black and white.

Current technology-based efforts are focusing on a nanotechnology approach to sorbent development for air purification applications. Titania nanotubes have recently been identified as extremely active under certain circumstances for decontamination of chemical warfare agents (CWAs). Furthermore, the possibility to add functional moieties to the nanotubes makes these materials an interesting candidate for evaluation against toxic industrial chemicals. This report summarizes the evaluation of titania nanotubes using nitrogen isotherm data, water and chloroethane adsorption - equilibria, and ammonia, cyanogen chloride (CK), and sulfur dioxide breakthrough data., Project Number BA07PRO104.

Current technology-based efforts are focusing on a nanotechnology approach to sorbent development for air purification applications. Metal-organic frameworks, or MOFs, are one novel class of materials that allow for specific functionalities to be designed directly into a porous framework. This report summarizes the evaluation of four MOFs using nitrogen isotherm data, temperature stability analyses, water and chloroethane adsorption equilibria, and ammonia, cyanogen chloride (CK), and sulfur dioxide breakthrough data., The original document contains color images. All DTIC reproductions will be in black and white. Prepared in collaboration with Hunter Applied Research Center, Edgewood, MD.

The vapor pressure of pinacolyl methyl phosphonofluoridate [O-( I ,2,2-trimethylpropyl)-methyl phosphonofluoridate. GD] has been measured between -20 and 50 C, using vapor saturation methodology. The current data are in good agreement with data previously measured.

Fielded air purification systems designed for removal of chemical warfare agents from air streams are based solely on activated, impregnated carbon, namely ASZM-TEDA. The broad chemical biological and radiological (CBR) threat presents a challenge to the traditional fielded CBR air purification technology, impregnated carbon filters. While these filters function well against a wide range of chemical agents, they possess several shortcomings such as limited capacity for agents that are removed by chemical reaction and/or weakly adsorbed, and minimal protection against several of the toxic industrial chemicals (TICs). Further, prolonged environmental exposure has been shown to reduce the capacity of these filters for agents that are removed by chemical reaction. The result of these shortcomings are (1) to limit the usefulness/protection capability of current NBC filters and (2) to impose change-out requirements that present logistical as well as disposal burdens to the user. Catalytic oxidation is an alternative air purification technology that is being investigated as a means of alleviating the above mentioned burdens. CATOX technology's target attributes include: (1) broad protection against chem-bio threat, (2) reduced logistics due to long operational life, (3) greatly increased capacity for CB agents and TICs compared to current NBC collective protection technologies and (4) lower energy costs relative to other regenerative filtration technologies., See also ADM001736. Presented at Proceedings for the Army Science Conference (24th) held in Orlando, FL on 29 Nov-2 Dec 2004.

Acetylcholinesterase (AChE) helps to regulate some of the most fundamental human biological operations such as motor function, sleep, attention, memory and emotions. A wide variety of AChE inhibitors exist, with health implications that range from fatal to benign. Strong AChE inhibitors such as some organophosphorus (OP) nerve agents (some of which can phosphorylate AChE irreversibly) are among the most powerful neurotoxins known and pose severe human health risks if misused. Weaker ligands, however, have been broadly studied as possible therapeutics for neural dysfunction disorders such as myasthenia gravis (MG), and various dementia such as Alzheimer's disease (AD). Weaker inhibitors have also been employed for nerve agent prophylaxis, although safety concerns continue to surround the standard prophylaxic formulations, especially pyridostiginine bromide (PB), suggesting that the criteria for their approval for military use might not be acceptable for broader civilian medical application. In fact, demonstrably safe and effective nerve agent prophylaxes remain elusive, despite a wealth of AChE inhibition data arising from AD and MG pharmaceutical research, as well as from pesticide toxicology studies., Presented at the DoD High Performance Computing Modernization Program (HPCMP) Users Group Conference (UGC), held in Williamsburg, Virginia on 7-11 June 2004. The original document contains color images. All DTIC reproductions will be in black and white. This article is from ADA492363 Proceedings of the HPCMP Users Group Conference 2004.