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A recursive multi-page assignment model is developed for effecting officer rotations in the U.S. Navy. Promotions and retirements are explicitly taken into account, just as in the earlier papers which are here extended to include other rotation-assignment processes and to accession of new officers. The developments used provide a structural form which is amenable to efficient computational procedures even for the dynamic case and an 'uncoupling' approach is also developed which allows further simplification and improvements in efficiency. This is accomplished in part by a transformation which takes the goal programming model with Markov transition probabilities into a rim adjustment solution process. Numerical examples are provided which illustrate the general case by reference to 2-period 3-officer classes rotations that involve assignments to both sea and shore duties. (Author)

The objective of this effort was to develop a strategy for improving distribution by the dynamic control of personnel rotational flows. A rotation simulation model was developed based on the concept of minimum tour lengths and flexible projected rotation dates (PRDs). Rotational flows were controlled to achieve sea distribution goals by length of service (LOS). The operations specialist (OS) rating was empirically tested. To achieve sea distribution goals for the OS rating, the model simulated sea tour lengths of 8 years for a small percentage of personnel commencing sea duty in the first 3 years of service. Adding a 5-year maximum sea-tour constraint while retaining the minimum shore-tour length at 1 year degraded the sea distribution slightly. In contrast, increasing the minimum shore tour to 2 years caused a significant degradation in sea distribution., See also Rept. no. NPRDC-SR-83-15, AD-A125 789.

The paper reports research on models for effective officer distribution to billets in the U.S. Navy in accordance with long-standing policy for rotation. A best fit of officer supply to billet demand in accordance with the indicated rules and priorities is developed as a goal programming model. Mathematical transformations have resulted in a satisfactory computerized format. Extensions to more general multiple attribute planning and multi-period planning are suggested and discussed. (Modified author abstract), Prepared in cooperation with Carnegie-Mellon Univ., Pittsburgh, Pa. Contract N00014-67-A-0314-0012.

A novel chiral helical imprinted polymer (MIP) has been prepared by bulk copolymerization of 3-methyl-4-vinylpyridine and a crosslinker using chiral S-mandelic acid as template. The resulting MIPs after removing the template show optical activity that is derived from the presence of chiral helical structures of poly(3-methyl-4-vinylpyridine) (P3M4VP) embedded within the MIP matrix. The basic functional monomer 3-methyl-4-vinylpyridine (3M4VP) was utilized with the acidic template to ensure good interaction between the template and the polymer. Divinylbenzene (DVB) and ethyleneglycoldimethacrylate (EGDMA) with widely varying degree of rigidity, flexibility, and polarity were selected as crosslinking agents. Using two different crosslinkers, it was possible to optimize the MIP for maximum specificity and selectivity. Spectroscopic methods such as FT-IR and 1H NMR were used to investigate the interaction between template and functional monomer. Scanning electron microscopy and nitrogen sorption analysis showed significant difference of the surface morphological characteristics between imprinted and non-imprinted polymers. Thermogravimetric analysis (TGA) was carried out to investigate thermal stability of MIPs and NIPs. The binding studies and the selectivity of the polymers were analyzed using UV-visible spectroscopy. The chiral secondary or higher structural ordering within the MIPs was examined using circular dichroism (CD) spectrometry. The polymer preparations were evaluated and compared with non-imprinted polymers for their ability to bind the template which is a measure of the specificity of the imprinted system. The nature and degree of crosslinking and other parameters like concentration of the template solution, solvent, and time which influences the binding of these imprinted polymers towards the print molecule were also investigated to optimize the imprinted system. The ability of the S-enantiomer imprinted polymer to bind the R-enantiomer was investigated.

Solid phase extraction (SPE) and solid phase microextraction (SPME) are extraction techniques that are used to separate analytes from aqueous samples. This study investigated the recovery of different pesticides using these two extraction techniques. SPME proved to be a better technique to use in the recovery of pesticides in contrast to SPE. Factors that effected the efficiency of solid phase extraction were selecting the proper extraction tube, using the correct solvent for conditioning the tube, and elution of the analytes from the tube with the appropriate amount of solvent. The factors effecting solid phase microexctraction were selecting the proper fiber and the amount of time for equilibrium to be reached between the analyte and the sorbent medium. The advantages of solid phase microextraction in contrast to solid phase extraction is that there is less time required to complete the extraction, repeated sample analysis using the same sample, and there is no waste to dispose.

Lignin is a biopolymer mainly formed from the trans-isomers of the three precursors: p-coumaryl alcohol, coniferyl alcohols, and sinapyl alcohol. Lignin components are analyzed by a twenty year old novel technique called GCXGC. Twenty-three lignin standards were injection into one-dimensional gas chromatography mass spectroscopy using 5 different column polarities. Dispersion Zone Density coefficient was developed to screen 40 predictive plots generated using two models derived from the retention indices. Ten predictive plots were chosen using the DZD coefficient which produced the best separation for the multifunctional lignin standards. The lignin standards were identified and characterize using the GCXGC. The quantitative analysis of the authentication of GCXGC analysis show better separation then the initial prediction for both models. CE-ESI-MS was the other method used for the analysis of lignin standards and Milled Wood Lignin.

Current methods utilized for the cleanup of drinking water primarily involve the use of chemical oxidants (e.g. chlorine, chlorine dioxide, ozone) to remove harmful bacteria and other pathogens. These processes create a number of disinfection by products (DBPs) that are potent toxins including halonitro-methanes and halo-acetic acids. In our research, we sought to examine the ability of supported metal oxides to accomplish disinfection without the production of toxic DBPs. In an effort to examine the interaction of bio-molecules with metal oxides surfaces, our group used Fourier transform infrared attenuated total reflectance (FT-IR/ATR) spectroscopy as well as Raman spectroscopy. We have mainly developed FT-IR/ATR techniques to examine the formation of bio-films on metal oxide surfaces in aqueous solution. Our technique involved the preparation of a thin layer of the oxide powder examined on the surface of the ATR crystal. Subsequent exposure of the film to bio-molecules and adsorption of the bio-molecules onto the surface was monitored through the infrared absorption of the biomolecules.

Blends containing methoxyoligooxyethyleneglycol (MPEGs) (MW 350 and 550) and bis(trifluoromethane)sulfonimide lithium (LiTFSI) salt were prepared by solution blending process using tetrahydrofuran (THF) as a solvent. The ionic conductivity of the blends of different compositions were determined at four temperatures i.e. 25C, 40C, 60C and 70C. A maximum ionic conductivity value of 3.9x10-3 S cm-1 at 25C was obtained for the blends containing MPEG-350 at an ethylene oxide to lithium salt ratio of 1:10. The ionic conductivity increases with increasing temperature and shows that the ion transport is aided by the segmental motion of the MPEG chains. 7Li NMR spectroscopy was used to study the nature and dynamics of the salt clusters in the blends KEY TERMS: Methoxypolyethylene glycol (MPEG), low molecular weight MPEGs, LiTFSI salt, Triglyme Boron, Ionic conductivity, 7Li NMR, Lithum-air battery, Liquid Organic Electrolytes, Ionic conductivity of blend of MPEGs/Triglyme Boron/LITFSI salt, Organic Chemistry, Polymer Chemistry

Imidazole functionalized ordered mesoporous silicate (MCM-IM) with high surface area was synthesized by the co-condensation of tetraethylorthosilicate, and n-[3 - (triethoxysilyl)propyl ]-4,5-dihydroimidazole, using cetyltrimethvlammonium bromide, CTAB, as a structure-directing agent in basic solution. Nitrogen porosimetry showed that MCM-IM exhibited typical Type IV adsorption-desorption isotherm, narrow average pore size distribution of 2.25 nm, surface area of 343 m2//g, and pore volume of 0.21 cm3 /g. MCM-IM exhibited a high affinity for 2,4-dinitrophenol and an adsorption capacity of 1.85 mmol/g was achieved. The adsorption was pH dependent with significant increase in adsorption capacity below pH 4. The sorption of 2,4-dinitrophenol on MCM-IM followed the Freundlich isotherm model, meaning, non-ideal, multiple, non ideal, multi-layer adsorption on heterogeneous surfaces. Asorption studies of Pb2+ on sulfonated and phosphonated activated carbon filters (ACF) were conducted in batch adsorption experiment. Kinetic experiment showed that lead (II) absorption reached equilibrium after 55 hours. Adsorption isotherm experiments showed that sulfonated activated carbons, S-ACF#1 and S-ACF#2 reached equilibrium capacities of 84.9 mg/g and 73.2 mg/g respectively, while phosphonated activated carbon. PVA-ACF, reached capacity of 66.2 mg/g. The adsorption was pH dependant and increased with pH. The sorption of Pb2+ on S-ACF#1 closely follows the Langmuir isotherm model, which means the sorption is monolayer and homogeneous surface. Sorption of Pb2+ on S-ACF#2 follows both Freundlich and Langmuir models and suggesting monolayer coverage on homogeneous surface or multi-layer on heterogeneous surfaces. Lead adsorption was not significantly affected by the prescene of competing alkali and alkali earth cations. except for Mg2+. In the presence of Mg2+ Pb2+ uptake was below 80%.

Quantum chemical calculations at M06-2X/6-311+G(2d,2p) level were employed to examine the structures, dissociation energies and vibrational spectra of complexes formed by Li+, Na+ and K+ with diphenylmethane, 1,2-diphenylethane, 1,3-diphenylpropane, [2.2]paracyclophane and [3.3]paracyclophane molecules. The effect of heteroatom substitution in the connecting chains of 1,3-diphenylpropane and [3.3]paracyclophane molecules on the binding affinity of cations with ligands was also included in this study. The complexes of [3.3] paracyclophane based molecules seem to have weak cation-pi interactions with metal ions Na+ and K+ when they were placed between two rings. The binding affinity of the metal ion varies from the ligands possessing single fusion to double fusion of alkyl chain (or hetero substituted alkyl chain) with two benzene rings. Vibrational frequencies related to metal-ligand stretching, C-H, N-H and P-H stretching are useful to characterize the complexes with different metal ions and their positional preference. KEY TERMS: Chemistry Science, Physical Chemistry

Following the methodology used in solgel chemistry to functionalize amorphous silica, organic functionalized mesoporous silica were prepared by the co-condensation of tetraethoxysilane and organoalkoxysilanes in the presence of surfactant templates. A series of titanium catalysts containing Ti-MCM-41 with different bridging and pendant organic functional groups (such as methyl triethoxysilane (MTEOS), phenyl triethoxysilane (PTEOS), diphenyl triethoxysilane (DPTEOS), bis (triethoxysilyl) ethane (BTSE), 1,4 bis(triethoxysiyl) benzene (BTSB), bis( triethoxysilyl) biphenyl (BTSDP) and two catalysts with different organic-inorganic ratios (90% TEOS with 10% phenyl, 70% TEOS with 30% phenyl) were synthesized. The catalysts were characterized by elemental analysis, XRD, FTIR, UVDRS, by solid state 13C and 29Si MAS NMR, and BET surface area analysis. The catalytic activities of the synthesized materials were evaluated for epoxidation of cyclohexene with TBIIP. The materials yielded improved conversion compared to the conversion results obtained from the traditional titanium containing mesoporous silica (Ti-MCM-41). The hydrophobic character of the synthesized catalysts was tested in the epoxidation of cyclohexene by using wet TBIIP. Ti-MCM41 with bridged organosilane showed almost the same conversion in the presence of water, while for Ti-MCM-41 with organosilane pendant groups. conversion decreased almost 36%. This implies that the silylation of the surface ofTi-MCM4I protected the active sites. The effect of substrate: oxidant molar ratio in these reactions were studied and high conversion, high selectivity were achieved at 1:1 molar ratio.

Functionalized nano materials have an expansive range of potential uses in bio medical applications. Functionalized synthetic (biocompatible and/or biodegradable) polymers that control or monitor cell signaling can be effective antagonists and promising drug candidates. We have developed a series of biodegradable functional polymer systems (with dimensions in the nanoscale) for creating allergy-effective drugs, using RBL mast cells and anti-2,4 dinitrophenyl (DNP) IgE antibodies that sensitize these cells by binding to high affinity IgE receptors(FceRI); creating polymers which are effective inhibitors of degranulation of mast cells stimulated by a potent allergen. The inhibition is possible because of the specific interaction of the functional polymers with the proteins (IgE) on the mast cell surfaces to control cell-signaling i.e. intelligent design of functional materials to manipulate cellular functions. The functional polymer system is based on biodegradable poly(lactides) carrying two, three or four 2,4-dinitrophenyl (DNP) groups. Although these DNP-functionalized ligands do not stimulate the granule exocytosis response, they have the potential to inhibit the robust response stimulated by other multivalent DNP ligands. These polymeric ligands are effective inhibitors of degranulation of mast cells stimulated by a potent allergen and thus are a potential model drug system. Additionally these lactide based polymers bind and achieve steady state binding with solution IgE within a few seconds at low concentrations; achieving about 75% of the binding below 0.2 uM. The preparation, characterization, processing and effectiveness of the functional polymers to control material-cell interactions will be discussed

The rapid development of polymer nanocomposites has received extensive attention over the last few decades. The ability to alter functionalities of composites, dramatically improving properties and performance at low filler content creates flexibility in designing materials for advanced applications in various industrial fields. This work focuses on nanocomposites relevant to the packaging and aerospace industries. This work evaluated the ability to homogeneously distribute nanomaterials into a polymer matrix, understand the effects on rheological properties, understand changes to microstructure and effects, and characterize properties of resulting nanocomposite. High torque melt mixing was used to disperse surface modified cellulose nanocrystals in a poly(lactic acid) (PLA) resin and graphene in a phenylethynyl terminated imide resin, PETI 298, using bulk graphite. Rheology, Raman spectroscopy, and X-Ray powder diffraction were applied for the understanding of changes to the microstructure and location of optimum loading by the determination of the percolation threshold. Thermomechanical performance was evaluated through TGA, DMA, and DSC. It was determined that graphene and short stacks of graphene could be dispersed and distributed at low loadings in PETI 298. As expected, the addition of graphitic material led to an increase in viscosity, but also caused a retardation of the cure which could be attributed to increased viscosity or quenching of free radicals. Changes to the microstructure were difficult to evaluate because of the competing chemistry occurring in the system but it could be determined that something significant occurs around 1 wt % at which the melt rheology and the microstructure behavior was different from other composites. It was further determined that the melt mixing process led to the formation of an ordered structured. Modification of the cellulose nanocrystals (m-CNC) with Cardura, glycidyl ester, provided no improvement to mechanical prope

Zeolites, having stable porous structures and high ion exchange capabilities are potential buffer materials that can be added to a soil matrix to improve the ion exchange ability. This study investigated the performance of various zeolites for the uptake of uranium as soluble UO2 2+, with the ultimate goal being to develop an in situ ion trap to immobilize potentially leachable residue in uranium contaminated soils. The natural zeolite, clinoptilolite and synthetic zeolites, K-L, LZY, 13X, and mordenite were evaluated for the uptake of UO2 2+ in both batch and column percolation studies. In the preliminary batch and column studies, mordenite, LZY, and K-L were most effective for uranium uptake. The pH was an important factor in governing which uranium species would be present in solution. In the pH controlled batch studies, mordenite demonstrated superior performance to the other zeolites as well as to a clay-soil for uranium uptake. With time, initially absorbed uranium was dissolved from the soil into solution whereas the zeolite showed no such release of uranium. Uranium uptake was found to be dependent on zeolite pore size, solution pH, cation concentrations, and amount of sorbent

Polymeric nanocomposites of poly(ethylene oxide) (PEO) and silica nanoparticle (Si02) were prepared by solution blending using dichloromethane. The goal of the study was to understand the effect of the silica nanoparticle on the morphology of poly(ethylene oxide) and the ability of the poly(ethylene oxide) to disperse the nanoparticle within the matrix. The study focused on the dispersion of the silica nanoparticle (20 run) as filler into poly(ethylene oxide) of molecular weights 8K and 20K. The nanocomposite products were powders.The products were characterized by Fourier Transform Infrared Spectroscopy, X-ray Diffraction, solid-state nuclear magnetic resonance spectroscopy (13C T1prelaxation rates), scanning electron microscopy and differential scanning calorimetry. Differential scanning calorimetry analysis results of the nanocomposites show thermal properties that are different from the individual components. The results show that the crystallinity is slightly reduced on increasing the Si02 nanoparticle loading. Increasing the SiO2 nanoparticles causes an increase in the Tt p relaxation rate of the PEO 8K suggesting effective dispersion of the nanoparticles within the matrix.Overall, the results suggest that the PEO 8K is better at dispersing the nanoparticles within the matrix compared with the PEO 20K.

In recent years, polymer-inorganic nanoparticle compositions have been a subject of considerable interest in order to achieve desired chemical, physical properties and mechanical properties. In this study a polymer nanocomposites have been prepared by incorporating silica nanoparticles (~20 nm) as fillers into poly(ethylene oxide) matrix. The composites of poly(ethylene oxide) and silica nanoparticles were prepared by solution blending. The product composites were powders. The thermal properties of the composites were investigated using the Differential Scanning Calorimetry. The Nuclear Magnetic Resonance (13C solid state, T1?), Atomic Force Microscopy, X-ray diffraction and Fourier Transform Infrared Spectroscopy were used to investigate the effect of the nanoparticles on the polymer matrix. The results suggest that the silica nanoparticles were reasonably well dispersed in the PEO 35K. The dispersion was accompanied by slightly reduced the crystallinity. However, with increasing the SiO2 nanoparticles the aggregation Phenomenon appears. Moreover, with increase in the MW of the PEO to 100K the dispersion of the nanoparticles decreased and aggregation phenomenon is observed even at lower of SiO2 contents. KEY TERMS: Polymer, Nano-particles, PEO, Composites, Characterization, Solution Blending, Inorganic Chemistry, Organic Chemistry, Polymer Chemistry

Ultraviolet photoemission spectroscopy measurements reveal that there is notable variation of the electron density of states in valence bands near the Fermi level. Evolution of the electronic structure of fluorinated graphene as a function ofthe applied electric bias is investigated. The experimental results demonstrate that the tailoring of electronic band structure correlates with the interlayer coupling tuned by the applied bias. The change in the work function of fluorinated graphene demonstrates the ability of fluorination to modify electron emissions characteristics of graphene.