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We establish an experimental method for a detailed investigation of inelastic collisional properties between ytterbium(Yb) in themetastable [3]P[2]state and ground state lithium (Li). By combining an optical lattice and a direct excitation to the [3]P[2]state we achieve high selectivity on the collisional partners.Using thismethodwe determine inelastic loss coefficients in collisions between [174]Yb([3]P[2]) with magnetic sublevels of mJ = 0 and -2 and ground state [6]Li to be (4.4 ± 0.3) x10[-11] cm3 s[-1] and (4.7 ± 0.8)x10-11 cm[3] s[-1], respectively. Absence of spin changing processes in Yb([3]P[2])-Li inelastic collisions at low magnetic fields is confirmed by inelastic loss measurements on themJ=0 state.Wealso demonstrate that our method allows us to look into loss processes in few-body systems separately.

This Annual Report presents a summary of investigations that have been carried out in the area of metastable phase research in fiscal year 2004 by the ISS science project office of JAXA. The aim of this research was to efficiently process a new metastable phase and to imply a function on the phase. The research items were the solidification of undercooled Silicon, and dendrite brake down, oxide glass processing, and ferroelectric behaviors of the oxide glass., 本論文は、JAXAのISS科学プロジェクト室準安定相研究チームにおいて2004年度に実施された研究成果の纏めである。この研究の目的は、準安定相の合成とその機能予測であった。2004年度の研究項目は、過冷シリコンを利用した過冷凝固過程研究、酸化物ガラスの強誘電的性質に関する研究である。主な研究成果は、低過冷度における板状シリコン成長仮説の確認、デンドライトブレークダウンの発生、流れと組織微細化について重要な結果が得られたこと、およびバリウムチタネート系ガラスでは巨大な誘電率を有する新たな準安定材料が合成されたことである。, 宇宙航空研究開発機構研究開発報告, JAXA Research and Development Report

Metastable polymeric materials were synthesized, formulated with additives and microcapsules, and then processed into films that served as substrates on which electronic devices were fabricated. New to this effort was the intentional development of depackaging cascades -- the rational design of materials that depolymerize on exposure to specific stimuli. In particular, we investigated acid-sensitive, depolymerizable poly(phthalaldehyde) (PPA), and thermally- and base-sensitive poly(olefin sulfone) (POS) polymers. Conditions for film preparation and fabrication of transient electronics on robust PPA and POS films were optimized. Three degradation triggers -- direct activation by photoacid generation, thermal activation, and mechanical rupture of acid-filled microcapsules -- were investigated.

A new technology of processing raw materials with the use of active alkali is suggested for bauxites of the Srednetimanskoe deposit; bauxite is opened at 300°C for 1 h. This technology makes it possible to increase the recovery of alumina to 94-98% and obtain red slimes and zeolite enriched with iron (58%) and titanium (4.8%); the environmental problem of storing red slimes is resolved. The blast-furnace smelting of such slimes makes it possible to obtain naturally doped cast iron and slag enriched with titanium and rare earth metals. When purifying (desiliconizing) the aluminate solution, a valuable product-sodium aluminum silicate hydrate of the zeolite type-is incidentally obtained. © 2013 Allerton Press, Inc.

A new technology of processing raw materials with the use of active alkali is suggested for bauxites of the Srednetimanskoe deposit; bauxite is opened at 300°C for 1 h. This technology makes it possible to increase the recovery of alumina to 94-98% and obtain red slimes and zeolite enriched with iron (58%) and titanium (4.8%); the environmental problem of storing red slimes is resolved. The blast-furnace smelting of such slimes makes it possible to obtain naturally doped cast iron and slag enriched with titanium and rare earth metals. When purifying (desiliconizing) the aluminate solution, a valuable product-sodium aluminum silicate hydrate of the zeolite type-is incidentally obtained. © 2013 Allerton Press, Inc.

A new class of molecule source , uniquely suited for spectroscopic study of energetic materials, has been designed and tested. This buffer gas cooled ablation source is used in combination with a Chirped Pulse millimeter Wave (CPmmW) spectrometer, which is capable of detecting polar molecular species transferred into the gas phase by laser ablation, laser initiated micro-detonation, laser vaporization, or reactions accompanying warming of a cryogenic matrix of an energetic material, such as a co-deposited redox combination. A factor of 100x improvement in molecule density per laser pulse relative to standard supersonic jet ablation sources has been demonstrated, in addition to a nearly factor of 10x reduction in Doppler width., The original document contains color images.

Growth of the liquid interlayer in the indium-tin system at 400 K in the process of contact melting in the nonstationary diffusion regime has been investigated experimentally. The contact pairs were composed of pure substances, solid solutions, and intermediate solid phases. The previously developed concepts have been extended to include the case where the existence of intermediate solid phases on both sides of the liquid phase should be taken into account. It follows from the results obtained that the concentration range of the liquid interlayer corresponds to the homogeneity range of the liquid phase in the phase diagram at the temperature of experiments. The results of the experiments can be explained based on the model according to which solid solutions and intermediate solid phases at the liquid/crystal interface arise due to the precipitation from the metastable melt supersaturated by the substance of the adjacent phase. © Pleiades Publishing, Ltd., 2012.

We report the development of general methods for trapping and cooling of atoms and molecules for atom optics and interferometry. The starting point of this work is the supersonic beam which produces a monochromatic, but fast beam of a noble-gas carrier gas. Atoms or molecules can generally be seeded or entrained into the supersonic beam flow. In one approach, ground-state helium atoms were slowed by reflection from Si(111) mounted on a spinning rotor. In order to stop and trap other atoms, we developed a multi-stage "atomic coilgun" consisting of miniature electromagnets with each one generating a short magnetic pulse. We were able to use this device to slow and then stop a supersonic beam of metastable neon atoms. The same apparatus was next used to stop a beam of molecular oxygen. In parallel, we have developed a general method of cooling that does not require a cycling transition and can be used to accumulate magnetically trapped atoms in an optical tweezer near the recoil temperature. This method, single-photon cooling, is based on a one-way wall for atoms and molecules. The combination of two methods provides a two-step solution to trapping and cooling that will work on most of the periodic table., The original document contains color images.

The apparent contact angles of dodecane droplets deposited on a 50:50 nylon:cotton blended woven fabric (NyCo) were measured, and the characteristics required for an ultraoleophobic surface were described. The metastable Cassie -Baxter model, a transition status from the original Cassie-Baxter model to the Wenzel model, was investigated to design ultraoleophobic surfaces and to understand the wetting behavior of such surfaces. Using chemical and geometrical modifications of NyCo, a surface having contact angles to dodecane of greater than 150 deg. and water contact angles of greater than 165 deg. has been prepared. Good agreement between the predicted and measured contact angles was obtained. Developing a superhydrophobic ultraoleophobic material has been achieved by two criteria: a low-surface-energy and a properly designed surface morphology., Published in the Journal of Materials Science, v45 p3247-3253, 2010.

A detailed collisional-radiative model is developed and coupled with a single-fluid, two-temperature convection model for the transport of shock-heated argon. The model is used in a systematic approach to examine the effects of the collision cross sections on the shock structure, including the relaxation layer and subsequent radiative-cooling regime. We present a comparison with previous experimental results obtained at the University of Toronto and the Australian National University, which serve as benchmarks to the model. It is shown that ionization proceeds via the ladder-climbing mechanism and is dominant from the upper levels as compared to the metastable states. Taking this into account, the present model is able to accurately reproduce the metastable populations in the relaxation zone measured in previous experiments, which is not possible with a two-step model. Numerical results of the radiative-cooling region are in close agreement with experiments and have been obtained without having to consider radiative transport. In particular, spontaneous free-bound emission to the upper levels together with Bremsstrahlung emission account for nearly all radiative losses; all other significant radiative processes, resulting in a transition into the groundstate, are mostly self-absorbed and have a lesser impact., For publication in the Journal of Applied Physics.

A plasma diagnostic technique has been experimentally demonstrated where optical emission measurements of relative intensities of spectral lines in the violet range were combined with available electron-impact cross sections to yield absolute Ar metastable species concentration. An enabling factor of this analysis was that the electron excitation pattern was quite different between the Ar ground state and the metastable state. The result of this pattern was that the optical spectrum was unique depending on whether the emission was generated by direct excitation from the ground state, or by stepwise excitation from one of the metastable states. This study has shown that a model combining Ar excitation cross sections can fit the experimental spectral distributions by varying the ratio of the metastable state density and the E/N within the discharge. The absolute density obtained through optical emission spectroscopy was compared to measurements using laser diode absorption in order to confirm the results., In-house contract.

The purpose of this demonstration was to evaluate the performance of metastable intermolecular composite (MIC) primers with compositions formulated from commercially available lead-free nanoscale powders. For these tests, the MIC composition was substituted for the lead styphnate-based primer composition currently used in conventional small caliber percussion primers. Small caliber percussion primers are used by the Army in small caliber ammunition and by the Navy in several CAD/PAD applications. The major objective of the program was to demonstrate that the performance of the MIC primers was equivalent to that of the lead styphnate primers in several Army and Navy applications. These performance objectives were met in that all MIC primers tested were found to meet all applicable military specifications. For Army small arms applications, the MIC primer was slightly slower than its lead styphnate counterpart but still within specifications., The original document contains color images.

MAIN TASKS: 1. Reaction Kinetics studies with spatially controlled Plasma Discharges 2. Effect of nanoparticle coupling with plasma enhanced combustion in flow reactors and flames. OBJECTIVES: * Development and validation of detailed low-temperature plasma fuel oxidation and ignition mechanisms, including surrogate fuels * Development of reduced plasma chemical fuel oxidation, ignition, and flameholding mechanisms which can readily be incorporated into predictive multi-dimensional reacting flow codes * Identification of specific processes critical to the enhancement of basic combustion phenomena by nonequilibrium plasmas, in particular processes involving radical and/or excited metastable species., Document consists entirely of briefing charts. U.S. Government or Federal Rights License. The original document contains color images.

We investigated multilayer and bilayer Ni/Si thin films by nanodifferential scanning calorimetry nano-DSC at ultrarapid scan rates, in a temperature-time regime not accessible with conventional apparatus. DSC experiments were completed at slower scan rates as well, where it was possible to conduct parallel rapid thermal annealing experiments for comparison. Post experimental characterization was accomplished by x-ray diffraction, and by transmission electron microscopy TEM and energy-filtered TEM of thin cross sections prepared by focused ion beam milling. We found that rate of heating has a profound effect on the resulting microstructure, as well as on the DSC signal. After heating to 560 C at 120 C/ s, the general microstructure of the multilayer was preserved, in spite of extensive interdiffusion of Ni and Si. By contrast, after heating to 560 C at 16 000 C/ s, the multilayer films were completely homogeneous with no evidence of the original multilayer microstructure. For the slower scan rates, we interpret the results as indicating a solid state diffusion-nucleation-growth process. At the higher scan rates, we suggest that the temperature increased so rapidly that a metastable liquid was first formed, resulting in complete intermixing of the multilayer, followed by crystallization to form solid phases. The integrated DSC enthalpies for both multilayer and bilayer films are consistent with this interpretation, which is further supported by thermodynamic predictions of metastable Ni/Si melting and solid state Ni/Si interdiffusion. Our results suggest that use of heating rates 10 000 C/ s may open new avenues for intermetallic micro- and nanofabrication, at temperatures well below those prevailing during explosive silicidation., Pub. in Journal of Applied Physics, v106, p104909-1/104909-6, 2009.

Metastable Xe atoms play an important role in the collisional radiative processes of dense xenon plasmas, including those of electric thrusters for space vehicles. Recent measurements and calculations of electron-excitation processes out of the metastable state have allowed for the development of a collisional radiative model for Xe near-infrared (NIR) emissions based on the population of the metastable level through radiative transitions, and based on depopulation through electron-impact excitation. A modified plasma radiative model incorporating newly computed electron-impact excitation cross sections using both relativistic distorted wave and semi-relativistic Breit-Pauli B-Spline R-matrix methods is presented. The model applies to optically thin, low-density regions of the thruster plasma and is most accurate at electron temperatures below 10 eV. The model is tested on laboratory spectral measurements of the D55 TAL and BHT-200 Hall thruster plasma NIR radiation. The metastable neutral fraction is determined to rise from 0.1 to slightly above. The electron temperature increases from ~2 to 10 eV, reaching a maximum around 15 eV. Electron temperatures derived with the modified model are approximately 20% lower than a previous version of the model that used an approximate approach to account for metastable population and line intensity enhancement., Published in Journal of Physics D: Applied Physics, v42 p185203-1 through 185203-8, 2009. Prepared in collaboration with Spectral Sciences, Inc., Burlington, MA; Drake University, Des Moines, IA; and Indian Institute of Technology, Roorkee, India. Sponsored in part by Air Force Office of Scientific Research (AFOSR), task no's 2301HS and 2303EP02; and National Science Foundation (NSF), grant no's PHY-0555226 and PHY-0757755.

Cell polarization plays a central role in the development of complex organisms. It has been recently shown that cell polarization may follow from the proximity to a phase separation instability in a bistable network of chemical reactions. An example which has been thoroughly studied is the formation of signaling domains during eukaryotic chemotaxis. In this case, the process of domain growth may be described by the use of a constrained time-dependent Landau-Ginzburg equation, admitting scale-invariant solutions la Lifshitz and Slyozov. The constraint results here from a mechanism of fast cycling of molecules between a cytosolic, inactive state and a membrane-bound, active state, which dynamically tunes the chemical potential for membrane binding to a value corresponding to the coexistence of different phases on the cell membrane. We provide here a universal description of this process both in the presence and in the absence of a gradient in the external activation field. Universal power laws are derived for the time needed for the cell to polarize in a chemotactic gradient, and for the value of the smallest detectable gradient. We also describe a concrete realization of our scheme based on the analysis of available biochemical and biophysical data. © 2009 IOP Publishing Ltd.

The objective of the research project is to explore the unimolecular and collisional excitation and decay mechanisms, reactivity and detectivity of molecules in metastable triplet states. The two primary research accomplishments are: (1) formulation and testing of a new and rigorous deconvolution procedure to completely characterize the mechanism of doorway mediated inter-system crossing and (2) observation of Franck-Condon and energy resonance controlled electronic excitation transfer between Xe 3P2 metastable atoms and N2 molecules.

Studies of high-density binary mixtures of simple molecular solids have uncovered a new aspect of high pressure chemistry. In contrast 10 the many previous studies on relatively inert mixtures, here we show that high pressures can lead 10 unexpected behavior in reactive compounds. Raman studies were performed on nitrogen and hydrogen binary alloys al room temperature to 83 GPa To pressures of 30 GPa, large vibron deviations from those of the pure materials suggest complex phase behavior. An unusual phase separation is observed near 35 GPa, which results in two distinct solid phases, one rich in both nitrogen and hydrogen and the other relatively amorphous. Spectroscopic signatures that can be attributed to N-N stretching were observed at high pressures., See also ADM002187. Proceedings of the Army Science Conference (26th), held in Orlando, Florida on 1-4 December 2008.

In this investigation, we observe magnetic resonance signals of metastable 129Xe sealed in a pyrex cell. We use external RF electrodes to generate the metastable Xe atoms. The metastable 129Xe is optically pumped by a diode laser tuned to the optical resonance of the metastable state. The hyperfine resonance signal of metastable 129Xe has been observed for the first time in a discharge cell, and a 20% polarization of metastable 129Xe atoms has been measured. We also measured the linewidths of the Zeeman transitions and hyperfine transitions, which we compare with previous measurements of Zeeman resonances.

Fourier transform infrared and Raman studies were performed on a N2/H2 mixture with a 2:1 ratio over a large pressure range (5-85 GPa) at room temperature in a diamond anvil cell. Based on the spectroscopic features observed within this pressure range and a thorough comparison to the vibronic modes of pure N2 and H2, the vibrational spectra have been assigned. The difference between the infrared and Raman vibron frequencies for pure N2 and H2 relative to those observed in the N2/H2 mixture is interpreted quantitatively with references to the possibility of new bonding arrangements or charge transfer between the components. High-pressure ultraviolet/visible electronic spectroscopy shows a broad absorption band that splits into two features near 30 GPa. The splitting of the absorption peak corroborates with the modifications that occur in the vibrational spectrum at similar pressures. Single-crystal x-ray diffraction studies were performed on the N2/H2 complex to near 17 GPa, and the similarities to pure nitrogen as well as the limitations of the experiments are discussed., The original document contains color images.

Percussion primers are used to ignite fixed ammunition propellant charges with a very high functional reliability. In order to achieve this high degree of reliability, extremely sensitive primary explosive compositions are selected as the initiating materials. Medium caliber ammunition percussion primers typically consist of lead styphnate and antimony sulfide. Although highly effective, these heavy material compounds were identified under 40 CFR 401.15 as toxic pollutants and should be replaced or eliminated. This project evaluated Metastable Intermolecular Composites (MIC) as potential replacements for the hazardous composition currently used in medium caliber ammunition percussion primers. MIC offers a non-toxic alternative to conventional military primers. Candidate MIC primers were evaluated in the laboratory for ignition characteristics and ballistically tested in 25-mm cartridges for ammunition requirement conformance., The original document contains color images. All DTIC reproductions will be in black and white.

Over course of this project, the objective has evolved based on the results obtained. In the original proposal, our objective was basically to study the interaction between the incident laser and the multiphase materials that are used in laser direct write deposition in order to produce metastable phases of materials for improved performance in a variety of applications such as energy storage and corrosion resistant systems. Based on our results described below, we extended this study in two significant ways. In the first modification, we have begun to develop a method based on a thick polymer absorbing layer to isolate the effects of mechanical and thermal stress on the transferred materials. In the second extension, we have developed methods to rapidly shape the intensity profile of the incident laser and begun preliminary studies on the effects of shape on the material response. Both of these important extensions were supported in part by AFOSR and will be continued in future studies.

The formation behavior of polycrystalline silicon thin films during the aluminum induced crystallization (AIC) process was investigated by scanning transmission electron microscopy (STEM) and in-situ heating transmission electron microscopy (TEM) observations. The STEM observation and electron dispersive X-ray spectroscopy (EDS) analysis of ex-situ heat-treated specimen revealed that the a-Si layer and Al layer switched the positions with each other during the heat treatment, resulting the crystallization of the a-Si layer. Furthermore, the in-situ heating TEM observation and EDS analysis of as-deposited specimen revealed the mixed state of Si and Al in an a-Si/Al film and the lateral growth of crystalline Si grain during the heating. The mechanism of AIC and switching layers were also discussed from the experimental results and the binary phase diagram of Al-Si system.

Percussion primer are used to ignite fixed ammunition propellant charges with a very high functional reliability. In order to achieve this high degree of reliability, extremely sensitive primary explosive compositions are selected as the initiating materials. Medium caliber ammunition percussion primers typically consist of lead styphnate and antimony sulfide. Although highly effective, these heavy metal compounds have been identified under 40 CFR 401.15 as toxic pollutants and should be replaced or eliminated. This project evaluated Metastable Intermolecular Composites (MIC) as potential replacements for the hazardous composition currently used in medium caliber ammunition percussion primers. MIC offers a non-toxic alternative to conventional military primers. Candidate MIC primers were evaluated in the laboratory for ignition characteristics and ballistically tested in 25mm cartridges for ammunition requirement conformance., The original document contains color images.

This grant has the objective of explaining the unusual properties of polymer-derived-ceramics (PDCs), so called because they are made directly from cross-linked polymers by controlled pyrolysis. The PDCs have unusual properties: (i) They remain structurally and chemically stable up to 1500 degrees C, (ii) They are amorphous in Bragg diffraction although small-angle-x ray-scattering shows the presence of nanodomains, (iii) POCs do NOT show steady state creep despite their amorphous structure, and (iv) PDCs exhibit viscoelasticity at high temperatures. The critical advance made in this grant is the development of a nanodomain model for the PDCs, which is validated by the experimental findings. The model consists of a graphene network interconnected in the form of nanodomains, about 1-5 nm in size. The graphene network stabilizes the amorphous structure of the ceramic. The unusual properties of PDCs are successfully explained by the nanodomain model. The PDCs are a new class of metastable ceramics that are likely to lead to revolutionary new technologies for high temperatures. Their amorphous nature is similar to that of polymers and metallic glasses. However, the chemical and structural stability of the PDCs at ultrahigh temperatures is unique.

Our work for the AFOSR has three primary components: Development of new quantum theory for the accurate description of molecular structure and spectra. Implementation of this new theory into general purpose computer programs (ACES II and pralel ACES III) to make it possible for many investigators, besides ourselves, to readily apply these new methods to problems of their interest. Application of these new methods to challenging molecules chosen to test the new methods, and to other systems of interest to AFOSR. These include high energy, density molecules, where the new methods allow an assessment of their energy content, stability, possible synthetic paths, activation barriers, and provide spectroscopic fingerprints for identification. We also make applications of interesting clusters, atmospheric systems, potential interstellar molecules, and to gas phase molecular reactions of the sort that can occur in flames., The original document contains color images.

This report results from a contract tasking Moscow State University as follows: Exploration of methods to control the radiative gamma- processes in nuclei is currently one of the most promising investigation directions of the modern Quantum Nucleonics - a new realm of contemporary Physics which spreads the basic conceptual ideas and methods of optical Quantum Electronics of atoms and molecules to the gamma-ray range and atomic nuclei and even anti-particles. One of the most important problems in this field is the generation of coherent gamma-radiation by a Gamma-ray Lasing (GRL) process which makes use of excited nuclei as an amplifying medium. The most likely medium for gamma-ray lasers is an ensemble of metastable nuclear isomers, Direct excitation of these isomeric states by electrons or X-ray photons will also create a deeper understanding of nuclear structure and properties., The original document contains color images.

This report results from a contract tasking CPAT as follows: The Grantee will perform theoretical modeling of point, surface, and volume high-pressure plasmas created using Micro Hollow Cathode Discharge sources. The primary goal is to better understand the fundamental physics of these discharges in order to optimize operating conditions and develop more efficient devices., Grant 033083, Universite Paul Sabatier, Toulouse, France. Annex 1: Mid-term grant rept. Annex 2: Journal article to appear in Appl Phys Lett. Annex 3: Journal article to appear in IEEE Trans Plasma Sci special issue on Images in Plasma Science. Annex 4: Conference paper to appear in the Proceedings of the Gas Disch Conf, 2005. The original document contains color images.

The formation, deactivation, and detection mechanisms of atoms and molecules in metastable electronically excited states are, in general, ill characterized. Yet the chemical and photophysical properties of such states are relevant to Air Force Missions in communication, upper atmosphere modeling, and high-speed vehicle tracking, and identification. The capabilities of a multispectral molecular beam apparatus have been demonstrated on the electronic spectrum of acetylene in the energy region of the first excited singlet state (S1), which is isoenergetic with high vibrational levels of the metastable triplet states (T1, T2, T3). This apparatus records two kinds of spectra (UV-LIF and SEELEM, respectively UltraViolet Laser Induced Fluorescence and Surface Electron Ejection by Laser Excited Metastables) simultaneously, which sample complementary groups of short- and long-lived rovibronic states. The most remarkable findings are: (i) UV-LIF spectra contain fully assignable eigenstates with dominant S1 or T3 character, where the T3 character acts as a "doorway" into states of dominant T1, T2 character that appear in SEELEM spectra; (ii) SEELEM spectra contain eigenstates that are rotationally fully assignable, regular in level pattern and relative intensity, yet vibrationally ergodic. Ergodicity in T23 coexists with doorway behavior in T1. Ergodicity, contrary to naive expectations, results in regular appearing spectra.

Important fundamental research over the past two decades has proven that the energy stored in metastable energy states of some nuclear isomers can be caused to be released from the isomer state by illuminating the nucleus with x-rays. Research ha proven that the long-lived naturally abundant isomer of t8OTa can be triggered to release the stored energy by irradiation with Bremsstrahlung x-irradiation. An understanding of this phenomenon within the standard model has now emerged, placing the physics of triggered energy release from isomer states upon a strong experimental and theoretical basis. The data from the March 2001 Bum-up experiment has now been fully analyzed. No bum-up duc to xynchrotron radiation was detected in this experiment due to both experimental limitations and the unlikelihood of ever observing bum-up in the Hf-i78m2 system for triggering enhancements of less than 10%. We suggest looking at alterative isomer systems with shorter half-lives, such as the Lu-I77m isomer.

This study investigates the carcinogenic and imunotoxic potential of embedded fragments of depleted uranium (DU) and a heavy-metal tungsten alloy (WA). Male Fischer 344 rats are surgically implanted with pellets of DU, WA, tantalum (inert metal, negative control), or nickel (known carcinogen, positive control). In Year 3 of this study, we found that implanted WA resulted in tumors at the implantation site in 100% of the rats. These tumors developed rapidly (within 18-22 weeks) after pellet implantation, exhibited extremely aggressive growth characteristics, and metastasized to the lung. The tumors were identified by histopathology and immunohistochemisty as high-grade pleomorphic rhabdomyosarcomas. In addition, rats in the high-dose WA group exhibited signs of polycythemia as early as one month after pellet implantation. Rats in the DU or tantalum groups showed no pellet-associated tumors for up to 2 years after implantation.

We have investigated several ways to prepare and characterize spectroscopically novel compounds of pure nitrogen:tetrazete N4 and pentazole anion N5. They are of interest to DARPA/AFOSR as potential new high energy density materials (HEDM)s and attractive propellants. Results of earlier, extensive theoretical work (quantum mechanical computations) consistently suggest that tetrazete should be a metastable compound with decomposition barrier of 60 kcal/mol, and it should contain 180 kcal/mol of energy with respect to the two dinitrogen molecules. We have carefully scrutinized several methods to prepare tetrazete and for its subsequent detection we have employed a number of spectroscopic techniques. Microwave, electrical discharge of gaseous nitrogen or fast atom bombardment of solid N2 (at 10K) produces highly reactive neutral and charged nitrogen fragments: N-atoms, N3 radicals and variety of ions. Majority of them recombine among themselves to form back dinitrogen or react will always-present trace amounts of impurities (mostly oxygen atoms) to produce nitrogen oxides. In our experiments we have condensed such mixtures on the low-temperature (5.6-20K) spectroscopic targets (salt windows or Pt-plated cupper). We have observed in IR absorption and Raman spectroscopy many lines characteristic for such compounds. In addition, we have detected absorption lines in the positions that are highly compatible with signals predicted by high-level quantum mechanical calculations for tetrazete. Due to the high symmetry of N4 only one IR absorption should be observable for a pure 14N4 or 15N4 isotopomers, making: the convincing and unambiguous proof difficult on the basis of such observation alone., Sponsored in part by DARPA.

HIGHLIGHTS FROM FISCAL 04 INCLUDE: DETERMINED THE OPTIMUM STRUCTURE AND VIBRATIONAL FREQUENCIES FOR A POLYMERIC NITROGEN SPECIES; EXPLORED A VARIETY OF OXYGEN SUBSTITUTED NITROGEN MOLECULES WHERE COOREINATE COVALENT BONDS TO OXYGEN ARE INTRODUCED; FINALIZED STUDIES OF AZACUBANES AND NITROZACUBANE; DID A STUDY OF THE NITROGEN OXIDE DIMER IN ITS GROUND AND EXCITED STATES., Report contains viewgraphs only.

In the first three years of this grant we have made considerable progress towards the goals stated in the original proposal. To date we have made clean sources for propargyl radical, CH3, F, Cl, Br and I. A total of 11 papers have been published during this grant period.

The objectives of our work for AFOSR include the following: Develop new theory based upon coupled-cluster theory, density functional theory, and density matrix functional theory to more accurately and easily describe the structure, spectra, and reactions of molecules. Implement these new methods into general-purpose computer programs, such as ACES II, to enable their routine application by non-experts to problems of their interest. Use these methods to provide numerical results for problems pertinent to AFOSR. These range from suggesting and exploring new rocket fuels, to plume identification and detection, to the detailed characterization of atmospheric species.

Nuclear isomers can store tremendous amounts of energy for long times and the prospects for a controlled "clean" release of this energy for applications have motivated considerable research. Significant insight into nuclear structure also results from studies of reactions that may cause a triggered energy release. The primary emphasis has been on reactions induced by externally-produced photons. These studies comprise a very narrow sub-field of nuclear physics that has often been poorly connected with the broader results of traditional investigations. This report details efforts under this grant to provide improved measurements of trigger processes for several isomers and to enhance the basic foundation of knowledge connecting triggering studies with the body of nuclear physics. The significance of the work is reflected by fifteen publications, including a result recognized by the American Physical Society as a top story in physics during 2000.

Considering new methods of nonstationary plasma diagnostics, we investigate an appearance of a new type of laser spectrum generation, which is a direct consequence of underlying principles of light-matter interaction. The spectrum "condensation" and amplification observed originate from the collective coherent interaction between atoms of a dense resonant medium trough the electromagnetic field., Pub. in International Conference on Phenomena in Ionized Gases (26th), v4 p217-218, July 2003. Prepared in cooperation with Institute of Laser Physics, Siberian Branch of RAS, Novosibirsk, Russia; Institute of Low Temperature Plasma Physics, Greifswald, Germany. This article is from ADA421147 International Conference on Phenomena in Ionized Gases (26th) Held in Greifswald, Germany on 15-20 July 2003. Proceedings, Volume 4

This paper presents the results of experiments conducted at the Research Foundation of SUNY, Stony Brook, NY, by Ph.D. and Master's degree students, undergraduates, visiting high school students, and senior visitors on the manipulation of metastable Helium atoms with polychromatic optical forces, and the study of their properties in dark states, entangled states, and other superpositions. These experiments led to the publication of several Doctoral Theses and other papers. Results are summarized for experiments conducted in the following areas: (1) velocity selective resonances and dark states, (2) stimulated optical compton scattering (SOCS), (3) beam slowing of Helium with the bichromatic force, (4) optical forces in frequency-modulated light, and (5) demonstration of adiabatic rapid passage. (2 figures, 17 refs.)

Nuclear isomers can store tremendous amounts of energy for long times for example, the 31- year metastable excited state of .178m2Hf stores 2.445 MeV per nucleus, or 1.2 GigaJoules per gram. These special states of certain isotopes therefore may prove useful as nuclear batteries, provided that a means is found by which to control (trigger) their energy release upon demand. The concentration of current research is on the use of externally-produced photons to serve as such a trigger. At this point, much research must be conducted to test this process and measure the important physical parameters, from which an evaluation of the feasibility of applications may be conducted. The x-ray generating and support equipment purchased through this award are permitting improved investigations of triggered gamma emission from nuclear isomers and have created, at Youngstown State University's X-Ray Effects Laboratories (XEL and XEL2), a unique facility for these studies.

The main goals of this experimental and theoretical project were to demonstrate the ability to create a uniform and diffuse nonequilibrium air plasma at atmospheric pressure, with an electron density of 10(13) cm(-3), a temperature below 2000 K, scalable to cubic meter size, with a low power budget. The Ohio State Consortium was focusing on use of efficient ionization sources, specifically e-beams and short pulse ionization wave generators, and on mitigation of electron removal by using laser energy addition to excite the vibrational modes of the air species. By this means, the power budget to sustain a stable plasma in low temperature, atmospheric pressure air is significantly reduced.The plasma decay time has been increased by more than two orders of magnitude. In addition, there have been major efforts to investigate the relevant ionization, electron removal, and energy transfer processes in such air plasmas, to model and analyze both e-beam and short pulse ionization sources in large volume air plasmas, to develop short pulse ionization wave generators, and to develop and employ advanced diagnostic methods to characterize the air plasmas produced. There have been major positive and novel results achieved in each of these areas., Prepared in cooperation with Princeton University, Dept. of Mech. and Aerospace Eng., Princeton, NJ.

Metastable, electronically excited states of atoms and small molecules have chemical and photophysical properties that are relevant to Air Force missions in communication, upper atmospheric modeling, and high speed vehicle detection; tracking, and identification A second-generation supersonic molecular beam apparatus with optimized multispectral capabilities has been designed, constructed, and tested. A series of experiments on acetylene has defined the fundamental mechanisms of three complementary signal channels: UV-LIF (Ultraviolet Laser Induced Fluorescence), IR-LIF (Laser Induced infrared Fluorescence from photofragments) and SEELEM (Surface Electron Ejection from Laser Excited Metastable molecules). Simultaneous measurements of S1, T1; and T3 characters of each eigenstate permit the causal mechanisms of photoexcitation, intersystem crossing, and collisional deexcitation to be identified. Powerful statistical pattern-recognition techniques have been developed which permit the disentanglement of key structural and dynamical features in the spectra and the ability to distinguish between direct (statistical) and doorway-mediated (causal) limiting mechanisms for intersystein crossing.

Certain cases are studied in which quantum dots showing no collective characteristics appear. It is demonstrated that isolated quantum dots are typical of the metastable arrays. The light radiated by these nanoislands has a narrower spectral band as compared to other dot arrays. This effect should be taken into account for the development of quantum dot lasers in particular for vertically cavity surface emitting lasers., This article is from ADA408025 Nanostructures: Physics and Technology International Symposium (9th), St. Petersburg, Russia, June 18-22, 2001 Proceedings

We have investigated several ways to prepare and characterize spectroscopically novel compounds of pure nitrogen: tetrazete N4 and pentazole anion N5. They are of interest to DARPA/AFOSR as potential new high energy density materials (HEDM)s and attractive propellants. Results of earlier, extensive theoretical work (quantum mechanical computations) consistently suggest that tetrazete should be a metastable compound with decomposition barrier of 60 kcal/mol, and it should contain 180 kcal/mol of energy with respect to the two dinitrogen molecules. We have carefully scrutinized several methods to prepare tetrazete and for its subsequent detection we have employed a number of spectroscopic techniques. Microwave, electrical discharge of gaseous nitrogen or fast atom bombardment of nolid N2 (at 10 K) produces highly reactive neutral and charged nitrogen fragments: N-atoms, N3 radicals and variety of ions. Majority of them recombine among themselves to form back dinitrogen or react with always-present trace amounts of impurities (mostly oxygen atoms) to produce nitrogen oxides.

Ferromagnetic properties and nanocrystallization process of soft ferromagnetic (Fe(0.99)Mo(0.01))78Si9B13 ribbons are studied by transmission electron microscope (TEM), X-ray diffraction (XRD), Mossbauer spectroscopy (MS), differential scanning calorimeters (DSC) and magnetization measurements. The Curie and crystallization temperature are determined to be T(sub c) = 665 K and T(sub x) = 750 K, respectively. The T(sub x) value is in well agreement with DSC measurement results. X-ray diffraction patterns had shown a good reconfirm of two metastable phases (Fe23B6, Fe3B) were formed under in-Situ nanocrystallization process. Of which these metastable phases embedded in the amorphous matrix have a significant effect on magnetic ordering. The ultimate nanocrystalline phases of alpha-Fe (Mo, Si) and Fe2B at optimum annealing temperature bad been observed respectively. It is notable that the magnetization of the amorphous phase decreases more rapidly with increasing temperature than those of nanocrystalline ferromagnetism, suggesting the presence of the distribution of exchange interaction in the amorphous phase or high metalloid contents., Pub. in Materials Research Society symposium proceedings; v. 674 pU1.3.1-U1.3.6, 2001. Prepared in cooperation with Prog. Molecular Simulation, Instituto Mexicano del Petroleo, Lazaro Cardenas, Mexico; ININ, Edo. de Mexico. This article is from ADA402512 Applications of Ferromagnetic and Optical Materials, Storage and Magnetoelectronics: Symposia Held in San Francisco, California, U.S.A. on April 16-20, 2001

The magnetic behaviour of the glass-covered metallic microwires with a wide compositional range of composition with soft and bard magnetic character is presented. The effect of conventional furnace and dc current annealing under dc axial magnetic field or without it as well as of a chemical etching on the magnetic properties of Co and Fe-based glass coated microwires has been studied. Such treatments modify the magnetic parameters. In particular, annealing under applied magnetic field (field annealing) can improve significantly such magnetic parameters as permeability. Such phenomenology can be interpreted considering the noticeable magnetic anisotropy induced by the combined effects of the magnetic field and strong internal stresses arising from the coating. Giant magnetoimpedance (GMI) effect was observed in nearly-zero magnetostrictive amorphous microwires. Upon careful heat treatment, FeCuNbSiB amorphous microwires devitrificate into nanocrystalline structure with large variety of magnetic parameters. Hard magnetic materials with coercivity up to 800 Oe were obtained as a result of decomposition of metastable phases in Co-Ni-Cu microwires as well as after crystallization process of FeCuNbSiB amorphous microwires., Pub. in Materials Research Society symposium proceedings; v. 674 pU7.5.1-U7.5.6, 2001. Prepared in cooperation with TAMag Madrid, Spain; Dept. Material Physics, Chemistry Facultyl, San Sebastian, Spain; Dept. Appl. Phys. I, EUITI, UPV/EHU, San Sebastian, Spain. This article is from ADA402512 Applications of Ferromagnetic and Optical Materials, Storage and Magnetoelectronics: Symposia Held in San Francisco, California, U.S.A. on April 16-20, 2001

The iron manganites Fe(x)Mn(3-x)O4 synthesis by soft chemistry method have been studied. The main difficulty is to obtain single phase spinel with high Mn content (0.4 < x < 1.3). Oxalate precursor powders of these materials with controlled shape and nanoscopic size have been prepared. The precursors are then heat treated with a H2/H2O/N2 gas mixture at low temperature. The resulting stoichiometric spinels are metastable phases with high specific surface area and are highly reactive toward oxygen. Therefore, these oxide can be oxidized in air at low temperature in order to produce mixed valence defect manganites Fe(x)Mn(3-x)O4+(sub delta) with a good reproducibility on the oxygen content. Although, some problems persist for the higher Mn contents, as the oxygen partial pressure for the reduction must be controlled precisely in order to produce the stoichiometric spinel at low temperature. The development of a low temperature reduction system, with oxygen partial pressure controlled by oxygen electrochemical pumping, is in progress., Pub. in Materials Research Society symposium proceedings; v. 674 pT3.5.1-T3.5.6, 2001. This article is from ADA402512 Applications of Ferromagnetic and Optical Materials, Storage and Magnetoelectronics: Symposia Held in San Francisco, California, U.S.A. on April 16-20, 2001

The metastable state SI in single crystals of orthorhombic Na2Fe(CN)5NO-2M2O (sodiumnitroprusside, SNP) was investigated by absorption spectroscopy. The development of the spectra with increasing population of SI was monitored and a new band in the red spectral range was assigned to SI. By comparing with density functional theory (DFT) calculations we were able to assign the band to the electronic transition 2b2 right arrow 7e. In addition we found that very strong holographic light scattering influences the absorption spectra measured with light polarization along the a- or b-axis of the crystals., Pub. in Materials Research Society symposium proceedings; v. 674 pV2.5.1-V2.5.6, 2001. Prepared in cooperation with the Laboratory for Neutron Scattering, Villigen, Switzerland; Condensed Matter Theory, Vllligen, Switzerland; Fachbereich Physik, Univ. of Osnabrueck, Germany. This article is from ADA402512 Applications of Ferromagnetic and Optical Materials, Storage and Magnetoelectronics: Symposia Held in San Francisco, California, U.S.A. on April 16-20, 2001