cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis of alternative flow sheets for the hybrid chlorine cycle

Abstract This paper reports the results of the most complete conceptual study conducted to date on hydrogen production using the hybrid chlorine cycle. Three alternative process flow sheets were developed, each capable of producing hydrogen at 35 °C (308 K) and 21 bar. The alternative approaches differ primarily in the way HCl is isolated and converted to hydrogen and chlorine gases. Aspen Plus™ simulation software was used to model the unit processes, supplemented where necessary by custom Excel spreadsheets. Major equipment was sized for a 200-million kg/yr plant; feasible materials of construction were identified; fixed capital investments and variable costs were estimated. Estimated net thermal efficiencies of the flow sheets range from 30% to 36%, based on the lower heating value of the hydrogen produced. With electrical power valued at $0.05/kWh, the cost of hydrogen produced by the hybrid chlorine cycle would be at least $3/kg. These results indicate that direct electrolysis of water is a more attractive way to produce hydrogen than any presently conceived version of the hybrid chlorine cycle.
Structure and Dipole Moment of (CF3)3CCCH

Abstract The microwave spectrum of (CF3)3CCCH has been recorded on the NIST Fourier-transform microwave spectrometer. The rotational constant for the principal isotopomer is found to be B0 = 690.87916(4) MHz and the dipole moment μ0 = 2.038(8) Debye. The microwave spectra of the three species with 13C substitution on the symmetry axis were observed in natural abundance. Combining rotational constants with the CF bond length and FCF bond angles previously determined in (CF3)3CH and (CF3)CI by electron diffraction, the bond lengths and bond angle around the central carbon atom could be determined and are in good agreement with the above mentioned molecules.
Divergence theorems in path space III: Hypoelliptic diffusions and beyond

Let x denote a diffusion process defined on a closed compact manifold. In an earlier article, the author introduced a new approach to constructing admissible vector fields on the associated space of paths, under the assumption of ellipticity of x. In this article, this method is extended to yield similar results for degenerate diffusion processes. In particular, these results apply to non-elliptic diffusions satisfying Hormander's condition.
An Approach to the Synthesis of the Manzamine Alkaloids Via the Vinylogous Amide PHotocycloAddition/Retro‐Mannich Fragmentation/Mannich Closure Cascade (pharM)

The application of the vinylogous amide [2+2] photocycloaddition/retro-Mannich fragmentation/Mannich closure cascade (pharM) to the synthesis of the pentacyclic ring system of the anti-leukemic marine alkaloid manzamine A is presented. Two approaches to the synthesis of the requisite pentacycle are described: (a) the transannular photocycloaddition of an 18-membered vinylogous amide; and (b) photocycloaddition of an acyclic vinylogous amide, followed by macrolactamization of the derived pharM closure product to generate the pentacyclic ring system.
Harada-Tsutsui Gauge Recovery Procedure: From Abelian Gauge Anomalies to the Stueckelberg Mechanism

Abstract Revisiting a path-integral procedure developed by Harada and Tsutsui for recovering gauge invariance from anomalous effective actions, it is shown that there are two ways to achieve gauge symmetry: one already presented by the authors, which is shown to preserve the anomaly in the sense of standard current conservation law, and another one which is anomaly-free, preserving current conservation. It is also shown that the application of the Harada–Tsutsui technique to other models which are not anomalous but do not exhibit gauge invariance allows the identification of the gauge invariant formulation of the Proca model, also done by the referred authors, with the Stueckelberg model, leading to the interpretation of the gauge invariant map as a generalization of the Stueckelberg mechanism.
Crystal nucleation in normal alkane liquids

The homogeneous nucleation of crystals in normal alkane liquids has been studied using a droplet technique for a range of alkanes between C16H34 and C5H12. The critical undercooling for nucleation, ΔTN, relative to the melting point TE, increases significantly with decreasing length of the alkane chain n: ΔTN/TE increases from 0.05 for C16H34 to 0.20 for C5H12, with separate variations noted for the odd‐n and even‐n alkanes. Use of a spherical nucleus model gives molar surface energies σM relative to the molar heat of fusion, ΔHM, which also increase significantly with decreasing n but show little odd–even variation: σM/ΔHM increases from 0.07 for C16H34 to 0.28 for C5H12. Because of the pronounced increase in surface energy with decreasing chain length, the model of a spherical nucleus is suggested to be inappropriate for the alkane liquids (at least for the high‐n alkanes). Using a preferred cylindrical nucleus model with separate side‐ and end‐surface energies, a side‐surface energy of about 6 erg cm−2...
Minimal Lepton Flavor Violation and renormalization group evolution of lepton masses and mixing

We study the renormalization group equations (RGEs) of the neutrino parameters in models of Minimal Lepton Flavor Violation. In such models, the RGEs can be described in terms of flavor spurions, such that only the coefficients depend on the specific model. We explicitly demonstrate this method for the SM and MSSM for both Type-I and Type-III seesaw models. For that purpose, the RGEs of neutrino parameters in the MSSM Type-III seesaw have been computed. We have extended this method to get the evolution equations at second order. The implications for leptogenesis are also discussed.
A plasma drag hypervelocity particle accelerator (HYPER)

Abstract Current debris models are able to predict the growth of the space debris problem and suggest that spacecraft must employ armor or bumper shields for some orbital altitudes now and that the problem will become worse as a function of time. The practical upper limit to the velocity distribution is on the order of 40 km/s and is associated with the natural environment. The velocity distribution of the man-made component peaks at 9–10 km/s with maximum velocity in the 14–16 km/s range. Experience in space has verified that the “high probability of impact” particles are in the microgram to milligram range. These particles can have very significant effects on coatings, insulators, and thin metallic layers. The surface of thick materials becomes pitted and the local debris component is enhanced by ejecta from the impact events. In this paper, the HYPER facility is described which produces a reasonable simulation of the man-made space debris spectrum in a controlled environment. The facility capability is discussed in terms of drive geometry, energetics, velocity distribution, diagnostics, and projectile/debris loading. The facility has been used to study impact phenomena on Space Station Freedom's solar array structure, the calibration of space debris collectors, other solar array materials, potential structural materials for use in the space, electrical breakdown in the space environment, and as a means of clarifying or duplicating the impact phenomena on surfaces which have been exposed in space.
Coxeter elements and periodic Auslander–Reiten quiver

In this paper we show that for a simply-laced root system a choice of a Coxeter element C gives rise to a natural construction of the Dynkin diagram, in which vertices of the diagram correspond to C-orbits in R; moreover, it gives an identification of R with a certain subset Iˆ of I×Z2h, where h is the Coxeter number. The set Iˆ has a natural quiver structure; we call it the periodic Auslander–Reiten quiver. This gives a combinatorial construction of the root system associated with the Dynkin diagram I: roots are vertices of Iˆ, and the root lattice and the inner product admit an explicit description in terms of Iˆ. Finally, we relate this construction to the theory of quiver representations.
Ionization Sources and Physical Conditions in the Diffuse Ionized Gas Halos of Four Edge-On Galaxies

Deep long-slit spectra of the diffuse ionized gas halos of the edge-on spiral galaxies NGC 4302 and UGC 10288 are presented. Emission lines are detected up to about z = 2 kpc in NGC 4302 and to nearly z = 3 kpc on the north side of UGC 10288. For both galaxies, the line ratios [N II]/Hα and [S II]/Hα increase with z in accordance with dilute photoionization models. Runs of [S II]/[N II] and for UGC 10288 the run of [O III]/Hα, however, are not explained by the models. Scale height determinations of their diffuse ionized gas (DIG) halos are generally lower than those of galaxies with more prominent extraplanar DIG features. These data, along with previously presented data for NGC 5775 and NGC 891, are used to address the issue of how DIG halos are energized. Composite photoionization/shock models are generally better at explaining runs of line ratios in these galaxies than photoionization models alone. Models of line ratios in NGC 5775 require a greater contribution from shocks for filamentary regions than for nonfilamentary regions to explain the run of [O III]/Hα. In either case, the [S II]/[N II] ratio is not well fit by the models. Composite models for UGC 10288 are successful at reproducing the run of [S II]/[N II] for all but the the highest values of [N II]/Hα; however, the run of [O III]/Hα versus [N II]/Hα does not show any discernible trend, making it difficult to determine whether or not shocks contribute to the layer's maintenance. We also examine whether the data can be explained simply by an increase in temperature with z in a pure photoionization model without a secondary source of ionization. Runs of [S II]/Hα, [N II]/Hα, and [S II]/[N II] in each of the four galaxies are consistent with such an increase. However, the runs of [O III]/Hα versus z in NGC 5775 and UGC 10288 require unusually high-ionization fractions of O++ that cannot be explained without invoking a secondary ionization source or at the very least a much higher temperature for the [O III]-emitting component than for the [S II]- and [N II]-emitting component. An increase in temperature with z is generally more successful at explaining the [O III]/Hα run in NGC 891, with the ionization fraction of O++ remaining relatively low and nearly constant with z.
Reliability for Networked Storage Nodes

High-end enterprise storage has traditionally consisted of monolithic systems with customized hardware, multiple redundant components and paths, and no single point of failure. Distributed storage systems realized through networked storage nodes offer several advantages over monolithic systems such as lower cost and increased scalability. In order to achieve reliability goals associated with enterprise-class storage systems, redundancy will have to be distributed across the collection of nodes to tolerate both node and drive failures. In this paper, we present alternatives for distributing this redundancy, and models to determine the reliability of such systems. We specify a reliability target and determine the configurations that meet this target. Further, we perform sensitivity analyses, where selected parameters are varied to observe their effect on reliability.
Size of Human Lower Thoracic and Lumbosacral Nerve Roots

Background : Nerve root size may determine degree of blockade after epidural or spinal anesthesia, but good measures of this fundamental anatomic parameter have not been published. Models of subarachnoid anesthetic distribution have lacked valid cauda equina dimensions. In this study, the author sought to measure cross-section areas of anterior and posterior roots at different levels for basic anthropomorphic analysis. Methods : Samples from 12 adult autopsy subjects were obtained from roots at levels T6 through S5. Cross-section area was determined by dividing the root sample weight by length and correcting for tissue density. Results : Roots were variably composed of as many as five easily separable independent strands. Areas of anterior roots are approximately half the area of posterior roots. On average, the largest anterior and posterior root is at S1, but this may occur at L3 through S2. There is a large degree of interindividual variability (e.g., range of posterior L5 root is 2.33-7.71 mm 2 ). Conclusions : The large size of low lumbar and high sacral roots may cause resistance to anesthetic effects, whereas the smaller dimensions of the thoracic roots may facilitate neural blockade. The small size of the low sacral roots may, in part, explain selective neurotoxic damage of these fibers after subarachnoid injections. Interindividual variability in root sizes may contribute to lack of predictability in anesthetic response.
An integrated collision prediction and avoidance scheme for mobile robots in non-stationary environments

A formulation that makes possible the integration of collision prediction and avoidance stages for mobile robots moving in general terrains containing moving obstacles is presented. A dynamic model of the mobile robot and the dynamic constraints are derived. Collision avoidance is guaranteed if the distance between the robot and a moving obstacle is nonzero. A nominal trajectory is assumed to be known from off-line planning. The main idea is to change the velocity along the nominal trajectory so that collisions are avoided. A feedback control is developed and local asymptotic stability is proved if the velocity of the moving obstacle is bounded. Furthermore, a solution to the problem of inverse dynamics for the mobile robot is given. Simulation results verify the value of the proposed strategy.
Enantioselective alkylations of tributyltin enolates catalyzed by Cr(salen)Cl: access to enantiomerically enriched all-carbon quaternary centers.

The catalytic asymmetric α-alkylation of tributyltin enolates with a range of primary alkyl halides is catalyzed by a chiral Cr(salen) complex. The reaction constitutes the first transition-metal-catalyzed system for α-alkylation of carbonyl substrates with this important class of electrophiles, providing access to five-, six-, and seven-membered ring ketone products bearing α-quaternary stereocenters in high enantioselectivity and synthetically useful yields.
Location on Tree Networks: P-Centre and n-Dispersion Problems

We consider two problems of locating facilities on trees. In the first, we wish to determine the location of n points so as to maximize the minimum distance between any pair. In the second we wish to locate p centers of a single type of facility so as to minimize the maximum distance between any point and the center nearest to it. We provide polynomial algorithms for both problems, of O|N|2 log n · log |N| for the first problem and of O|N|2 log p for the second, where |N| is the number of nodes in the tree.
Astrophysical constraints on the couplings of axions, majorons, and familons.

The spontaneous breaking of a global symmetry leads to the existence of Nambu-Goldstone bosons which, through their coupling to electrons and/or photons, can transport energy from the cores of stars and affect significantly the course of stellar evolution. We find by following in detail the evolution of stars that if the couplings to electrons and/or photons is too strong, helium never ignites\char22{}in contradiction with the observational evidence. Our limits restrict the axion mass to less than 0.01 eV, the familon breaking scale to g7\ifmmode\times\else\texttimes\fi{}${10}^{9}$ Gev, and the triplet majoron vacuum expectation value to l9 keV.
High-Performance Silicon Photoanodes Passivated with Ultrathin Nickel Films for Water Oxidation

Silicon’s sensitivity to corrosion has hindered its use in photoanode applications. We found that deposition of a ~2-nanometer nickel film on n-type silicon (n-Si) with its native oxide affords a high-performance metal-insulator-semiconductor photoanode for photoelectrochemical (PEC) water oxidation in both aqueous potassium hydroxide (KOH, pH = 14) and aqueous borate buffer (pH = 9.5) solutions. The Ni film acted as a surface protection layer against corrosion and as a nonprecious metal electrocatalyst for oxygen evolution. In 1 M aqueous KOH, the Ni/n-Si photoanodes exhibited high PEC activity with a low onset potential (~1.07 volts versus reversible hydrogen electrode), high photocurrent density, and durability. The electrode showed no sign of decay after ~80 hours of continuous PEC water oxidation in a mixed lithium borate–potassium borate electrolyte. The high photovoltage was attributed to a high built-in potential in a metal-insulator-semiconductor–like device with an ultrathin, incomplete screening Ni/NiO x layer from the electrolyte.
Visual simulation of shockwaves

We present an efficient method for visual simulations of shock phenomena in compressible, inviscid fluids. Our algorithm is derived from one class of the finite volume method especially designed for capturing shock propagation, but offers improved efficiency through physically-based simplification and adaptation for graphical rendering. Our technique is capable of handling complex, bidirectional object-shock interactions stably and robustly. We describe its applications to various visual effects, including explosion, sonic booms and turbulent flows. Furthermore, we explore parallelization schemes and demonstrate the scalability of our method on shared-memory, multi-core architectures.
The Spot Model for random-packing dynamics

Abstract The diffusion and flow of amorphous materials, such as glasses and granular materials, has resisted a simple microscopic description, analogous to defect theories for crystals. Early models were based on either gas-like inelastic collisions or crystal-like vacancy diffusion, but here we propose a cooperative mechanism for dense random-packing dynamics, based on diffusing “spots” of interstitial free volume. Simulations with the Spot Model can efficiently generate realistic flowing packings, and yet the model is simple enough for mathematical analysis. Starting from a non-local stochastic differential equation, we derive continuum equations for tracer diffusion, given the dynamics of free volume (spots). Throughout the paper, we apply the model to granular drainage in a silo, and we also briefly discuss glassy relaxation. We conclude by discussing the prospects of spot-based multiscale modeling and simulation of amorphous materials.
Spectroscopic Signature of Aging in δ-Pu(Ga)

Resonant photoemission, a variant of photoelectron spectroscopy, has been demonstrated to have sensitivity to aging of Pu samples. The spectroscopic results are correlated with resistivity measurements and are shown to be the fingerprint of mesoscopic or nanoscale internal damage in the Pu physical structure. This means that a spectroscopic signature of internal damage due to aging in Pu has been established.
The separation of the intramolecular isotope effect for the cytochrome P-450 catalyzed hydroxylation of n-octane into its primary and secondary components

The intramolecular isotope effect for the cytochrome P-450b omega-hydroxylation of (1,1,1-/sup 2/H/sub 3/)-n-octane was separated into its primary and secondary components by the method of Hanzlik. The primary isotope effect was found to lie between 7.3 and 7.9 while the secondary isotope effect was found to lie between 1.09 and 1.14. These data are consistent with a highly symmetrical transition state with 15% of the observed isotope effect being due to secondary isotope effects. Although the system was found to depart from the rule of the geometric mean, the phenomenon could not be attributed to tunneling.
Pressure-induced structural changes in La1.85Sr0.15CuO4

Abstract The structure of La 1.85 Sr 0.15 CuO 4 has been studied versus pressure to 0.53 GPa at room temperature using neutron powder diffraction. Contrary to a recent report [1], we observe no anomalous change in the Cu-O(2) (apical) bond length in the pressure range studied. However, the pressure-induced shortening of this bond is larger than the cell compression along the same direction, suggesting that pressure-induced charge transfer may provide an explanation for the effect of pressure on T c .
Catalyzed combustion of hydrogen–oxygen in platinum tubes for micro-propulsion applications

Abstract The present investigation addresses the need to understand the physics and chemistry involved in propellant combustion processes in micro-scale combustors for propulsion systems on micro-spacecraft. These spacecraft are planned to have a mass less than 50 kg with attitude control estimated to be in the 1–10 mN thrust class. Micro-propulsion devices behave differently than macro-scale devices because of the differences in magnitude of flow rates and heat transfer. Reducing the combustor size increases the relative surface area, increasing the heat loss, and as combustors are continuously reduced in size, they approach the quenching dimensions of the propellants. Combustors of this size are expected to significantly benefit from surface catalysis processes. A miniature flame tube apparatus is chosen for this study because microtubes can be easily fabricated from known catalyst materials, and their simplicity in geometry can be used in fundamental simulations for validation purposes. Experimentally, we investigated the role of catalytically active surfaces within 0.4 and 0.8 mm internal diameter microtubes, with special emphases on ignition processes in fuel rich gaseous hydrogen and gaseous oxygen. Calculations of flame thickness and reaction zone thickness predict that the diameters of our test apparatus are below the quenching diameter of the propellants in most atmospheric test conditions. The temperature and pressure rise in resistively heated platinum microtubes and the exit hydrogen concentration were used as an indication of exothermic reactions. Data on imposed heat flux/preheat temperature required to achieve ignition versus mass flow rate are presented. With a plug flow model, the experimental conditions were simulated with detailed gas-phase chemistry and surface kinetics. Computational results, in general, support the experimental findings.
Semiconducting polymers: the Third Generation

There has been remarkable progress in the science and technology of semiconducting polymers during the past decade. The field has evolved from the early work on polyacetylene (the First Generation material) to a proper focus on soluble and processible polymers and co-polymers. The soluble poly(alkylthiophenes) and the soluble PPVs are perhaps the most important examples of the Second Generation of semiconducting polymers. Third Generation semiconducting polymers have more complex molecular structures with more atoms in the repeat unit. Important examples include the highly ordered and crystalline PDTTT and the ever-growing class of donor–acceptor co-polymers that has emerged in the past few years. Examples of the latter include the bithiophene–acceptor co-polymers pioneered by Konarka and the polycarbazole–acceptor co-polymers pioneered by Leclerc and colleagues. In this tutorial review, I will summarize progress in the basic physics, the materials science, the device science and the device performance with emphasis on the following recent studies of Third Generation semiconducting polymers: stable semiconducting polymers; self-assembly of bulk heterojunction (BHJ) materials by spontaneous phase separation; bulk heterojunction solar cells with internal quantum efficiency approaching 100%; high detectivity photodetectors fabricated from BHJ materials.
Anomalies, dualities, and topology of D = 6 N = 1 superstring vacua

We consider various aspects of compactifications of the Type 1/heterotic Spin(32)/Z2 theory on K3. One family of such compactifications includes the standard embedding of the spin connection in the gauge group, and is on the same moduli space as the compactification of the heterotic E8 × E8 theory on K3 with instanton numbers (8,16). Another class, which includes an orbifold of the Type I theory recently constructed by Gimon and Polchinski and whose field theory limit involves some topological novelties, is on the moduli space of the heterotic E8 × E8 theory on K3 with instanton numbers (12,12). These connections between Spin(32)/Z2 and E8 × E8 models can be demonstrated by T-duality, and permit a better understanding of nonperturbative gauge fields in the (12,12) model. In the transformation between Spin(32)/Z2 and E8 × E8 models, the strong/weak coupling duality of the (12,12) E8 × E8 model is mapped to T-duality in the Type I theory. The gauge and gravitational anomalies in the Type I theory are canceled by an extension of the Green-Schwarz mechanism.
Employee proactivity in organizations: A comparative meta‐analysis of emergent proactive constructs

This meta-analysis of 103 independent samples provides a comparative evaluation of the relationships associated with four emergent proactive constructs including proactive personality, personal initiative, voice, and taking charge. This study investigates comparative relationships among these focal proactive constructs and key organizational variables (i.e., job performance), personality traits (i.e., the Big Five), and individual variables (i.e., work experience). Results reveal significant correlations between proactivity and performance, satisfaction, affective organizational commitment, and social networking. Results also provide evidence that differentiates focal proactive constructs from the Big Five as well as individual differences in work experience, age, and general mental ability. Current progress towards a more integrative understanding of proactivity research is discussed.
Comment on ‘Model-dependence of Shapiro time delay and the “speed of gravity/speed of light” controversy’

In a recent paper published in (2004 Class. Quantum Grav. 21 3803) Carlip used a vector–tensor theory of gravity to calculate the Shapiro time delay by a moving gravitational lens. He claimed that the relativistic correction of the order of v/c beyond the static part of the Shapiro delay depends on the speed of light c and, hence, the Fomalont–Kopeikin experiment is not sensitive to the speed of gravity, cg. In this comment we analyse Carlip's calculation and demonstrate that it implies a gravitodynamic (non-metric) system of units based on the principle of the constancy of the speed of gravity but it is disconnected from the practical method of measurement of astronomical distances based on the principle of the constancy of the speed of light and the SI metric (electrodynamic) system of units. Readjustment of theoretically admissible but practically unmeasurable coordinates of Carlip to the SI metric system of units used in the JPL ephemeris reveals that the velocity-dependent correction to the static part of the Shapiro time delay does depend on the speed of gravity, cg, as shown by Kopeikin (2004 Class. Quantum Grav. 21 3251). This analysis elucidates the importance of employing the metric system of units for physically meaningful interpretation of gravitational experiments.
Pulsatile administration of low-dose gonadotropin-releasing hormone. Ovulation and pregnancy in women with hypothalamic amenorrhea

We administered pulsatile low doses of gonadotropin-releasing hormone (GnRH) (1 to 5 μg) to patients whose anovulation was caused by relative and absolute deficiency of endogenous GnRH. Eight such patients, including one with previous pituitary stalk transection, were treated during a total of 23 cycles; pulses of GnRH were administered via a portable pump every 96 or 120 minutes. Activation of pituitary-ovarian function with orderly development of a single dominant follicle, a luteinizing hormone surge, and ovulation occurred in 20 of the 23 cycles. The other three cycles were anovulatory. All patients responded, and five (62%) of the eight conceived, for a total of seven pregnancies and four full-term deliveries of normal infants. This study demonstrates that small pulsatile doses of GnRH can activate cyclic pituitary-ovarian function in hypogonadotropin-acyclic women and induce ovulation resulting in pregnancy and live birth. ( JAMA 1983;250:2937-2941)
Obtaining Normal Tissue Constraints Using Intensity Modulated Radiotherapy (IMRT) in Patients with Oral Cavity, Oropharnygeal, and Laryngeal Carcinoma

The purpose of this study was to evaluate normal tissue dose constraints while maintaining planning target volume (PTV) prescription without reducing PTV margins. Sixteen patients with oral cavity carcinoma (group I), 27 patients with oropharyngeal carcinoma (group II), and 28 patients with laryngeal carcinoma (group III) were reviewed. Parotid constraints were a mean dose to either parotid < 26 Gy (PP1), 50% of either parotid < 30 Gy (PP2), or 20 cc of total parotid < 20 Gy (PP3). Treatment was intensity modulated radiation therapy (IMRT) with simultaneous integrated boost (SIB). All patients met constraints for cord and brain stem. The mandibular constraints were met in 66%, 29%, and 57% of patients with oral, oropharyngeal, and laryngeal cancers, respectively. Mean dose of 26 Gy (PP1) was achieved in 44%, 41%, and 38% of oral, oropharyngeal, and laryngeal patients. PP2 (parotid constraint of 30 Gy to less than 50% of one parotid) was the easiest to achieve (group I, II, and III: 82%, 76%, and 78%, respectively). PP3 (20 cc of total parotid < 20 Gy) was difficult, and was achieved in 25%, 17%, and 35% of oral, oropharyngeal, and laryngeal patients, respectively. Mean parotid dose of 26 Gy was met 40% of the time. However, a combination of constraints allowed for sparing of the parotid based on different criteria and was met in high numbers. This was accomplished without reducing PTV-parotid overlap. What dose constraint best correlates with subjective and objective functional outcomes remains a focus for future study.
PREPARATION OF ALKENYL FISCHER CARBENE COMPLEXES VIA ALDOL CONDENSATION WITH ENOLIZABLE ALDEHYDES

Abstract A method for the preparation of alkenyl chromium carbene complexes is described by an aldol condensation of enolizable aldehydes. The aldol condensation of pentacarbonyl methy(methoxy)methylene chromium is best performed with an aliphatic aldehyde that is precomplexed with tin tetrachloride and the elimination step is optimal with mesyl chloride and triethylamine.
Facile and General Synthesis of 2-, 3-, or 4-[(Dialkylamino)alkyl]pyridines and -piperidines

Reaction of (dialkylamino)alkyl chloride with picolyllithiums provides the corresponding pyridine derivatives from which the piperidines are obtained by catalytic hydrogenation.
A hierarchical Bayesian network for event recognition of human actions and interactions

Recognizing human interactions is a challenging task due to the multiple body parts of interacting persons and the concomitant occlusions. This paper presents a method for the recognition of two-person interactions using a hierarchical Bayesian network (BN). The poses of simultaneously tracked body parts are estimated at the low level of the BN, and the overall body pose is estimated at the high level of the BN. The evolution of the poses of the multiple body parts are processed by a dynamic Bayesian network (DBN). The recognition of two-person interactions is expressed in terms of semantic verbal descriptions at multiple levels: individual body-part motions at low level, single-person actions at middle level, and two-person interactions at high level. Example sequences of interacting persons illustrate the success of the proposed framework.
ON THE BREAKUP OF VISCOUS LIQUID THREADS

A one-dimensional model evolution equation is used to describe the nonlinear dynamics that can lead to the breakup of a cylindrical thread of Newtonian fluid when capillary forces drive the motion. The model is derived from the Stokes equations by use of rational asymptotic expansions and under a slender jet approximation. The equations are solved numerically and the jet radius is found to vanish after a finite time yielding breakup. The slender jet approximation is valid throughout the evolution leading to pinching. The model admits self-similar pinching solutions which yield symmetric shapes at breakup. These solutions are shown to be the ones selected by the initial boundary value problem, for general initial conditions. Further more, the terminal state of the model equation is shown to be identical to that predicted by a theory which looks for singular pinching solutions directly from the Stokes equations without invoking the slender jet approximation throughout the evolution. It is shown quantitatively, therefore, that the one-dimensional model gives a consistent terminal state with the jet shape being locally symmetric at breakup. The asymptotic expansion scheme is also extended to include unsteady and inertial forces in the momentum equations to derive an evolution system modelling the breakup of Navier-Stokes jets. The model is employed in extensive simulations to compute breakup times for different initial conditions; satellite drop formation is also supported by the model and the dependence of satellite drop volumes on initial conditions is studied.
Age, Metallicity, and the Distance to the Magellanic Clouds from Red Clump Stars

We show that the luminosity dependence of the red clump stars on age and metallicity can cause a difference of up to 0.6 mag in the mean absolute I magnitude of the red clump between different stellar populations. We show that this effect may resolve the apparent ≈ 0.4 mag discrepancy between red clump-derived distance moduli to the Magellanic Clouds and those from, e.g., Cepheid variables. Taking into account the population effects on red clump luminosity, we determine a distance modulus to the LMC of 18.36 ± 0.17 mag, and to the SMC of 18.82 ± 0.20 mag. Our alternate red clump LMC distance is consistent with the value (m-M)LMC=18.50 ± 0.10 adopted by the Hubble Space Telescope Cepheid Key Project. We briefly examine model predictions of red clump luminosity and find that variations in helium abundance and core mass could bring the Clouds closer by some 0.10-0.15 mag, but not by the ≈ 0.4 mag that would result from setting the mean absolute I magnitude of the Cloud red clumps equal to the that of the solar neighborhood red clump.
A System-Optimization Perspective for Supply Chain Network Integration: The Horizontal Merger Case

Abstract In this paper, we present a new theoretical framework for the quantification of strategic advantages associated with horizontal mergers through the integration of supply chain networks. The framework is a system-optimization one in which each firm is represented as a network of economic activities associated with manufacturing, distribution, and storage and with explicit capacities imposed on the links. We present the models pre- and post-horizontal mergers and define a measure for the quantification of the gains, if any, associated with the mergers. We illustrate the framework with several numerical examples. For simple classes of mergers we derive formulae for the strategic advantages.
Reaction Studies of the Selective Reduction of NO by Various Hydrocarbons

Abstract A number of factors affecting the behavior of ZSM-5 and Ferrierite zeolites have been studied and implications concerning mechanism have been deduced. Increasing the loading of the ZSM-5 with Co2+ is shown to increase both the selective catalytic reduction (SCR) of NO and hydrocarbon combustion activities, but not to alter the selectivity under a given set of reaction conditions. The latter was nearly constant at all temperatures and valued at unity up to 673 K, where it precipitously fell at higher temperature. Selectivity was also a function of space velocity and of the NO/C4H10 ratio. Both SCR and combustion followed similar patterns with different charge balancing cations (including H) with a few notable exceptions. The shifts in temperature required to obtain a given conversion of NO to N2 were relatively minor compared with those required for constant combustion. NO and NO2 were equivalent in SCR in the presence of excess O2. In the absence of O2, NO2 was the better oxidant at low temperature although NO became quite effective above 800 K. The tabulated data at various temperatures showed a strong molecular sieve effect in the SCR reaction when neononane was employed, but not for the combustion reaction. None of the other molecules employed showed this behavior. Plots of conversion of NO to N2 vs conversion of hydrocarbon to CO2 correlated the data for all hydrocarbons, regardless of size, on single curves, except for neononane over Co- and CH4 over CuZSM-5. Even HZSM-5 behaved in this way. A further interesting molecular sieve effect was found when reactions over CoFer (Ferrierite) were compared with those over CuZSM-5.
Oxidative Decontamination of Tritiated Materials Employing Ozone Gas

The Princeton Plasma Physics Laboratory has developed a process by which to significantly reduce surface and near surface tritium contamination from various materials. The Oxidative Tritium Decontamination System (OTDS) reacts gaseous state ozone (accelerated by presence of catalyst), with tritium entrained/deposited on the surface of components (stainless steel, copper, plastics, ceramics, etc.) for the purpose of activity reduction by means of oxidation-reduction chemistry. 1 In addition to removing surface and near surface tritium contamination from (high monetary value) components for re-use in non-tritium environments, the OTDS has the capability of removing tritium from the surfaces of expendable items, which can then be disposed of in a less expensive fashion. The OTDS can be operated in a batch mode by which up to approximately 20kg of tritium contaminated (expendable) items can be processed and decontaminated to levels permissible for free release (< 16.66Bq/100cm 2 ). This paper will discuss the OTDS process, the level of tritium surface contamination removed from various materials, and a technique for deep scrubbing tritium from subsurface layers.
Human motion estimation from a reduced marker set

Motion capture data from human subjects exhibits considerable redundancy. In this paper, we propose novel methods for exploiting this redundancy. In particular, we set out to find a subset of motion-capture markers that are able to provide fast and high-quality predictions of the remaining markers. We then develop a model that uses this reduced marker set to predict the others. We demonstrate that this subset of original markers is sufficient to capture subtle variations in human motion.We take a data-driven modeling approach to learn piecewise local linear models from a marker-based training set. We first divide motion sequences into segments of low dimensionality. We then retrieve a feature vector from each of the motion segments and use these feature vectors as modeling primitives to cluster the segments into a hierarchy of local linear models via a divisive clustering method. The selection of an appropriate linear model for reconstruction of a full-body pose is determined automatically via a classifier driven by a reduced marker set. After offline training, our method can quickly reconstruct full-body human motion using a reduced marker set without storing and searching the large database. We also demonstrate our method's ability to generalize over a variety of motions from multiple subjects.
Mechanistic and Computational Studies of Oxidatively-Induced Aryl−CF3 Bond-Formation at Pd: Rational Design of Room Temperature Aryl Trifluoromethylation

This article describes the rational design of first generation systems for oxidatively induced Aryl−CF3 bond-forming reductive elimination from PdII. Treatment of (dtbpy)PdII(Aryl)(CF3) (dtbpy = di-tert-butylbipyridine) with NFTPT (N-fluoro-1,3,5-trimethylpyridinium triflate) afforded the isolable PdIV intermediate (dtbpy)PdIV(Aryl)(CF3)(F)(OTf). Thermolysis of this complex at 80 °C resulted in Aryl−CF3 bond-formation. Detailed experimental and computational mechanistic studies have been conducted to gain insights into the key reductive elimination step. Reductive elimination from this PdIV species proceeds via pre-equilibrium dissociation of TfO− followed by Aryl−CF3 coupling. DFT calculations reveal that the transition state for Aryl−CF3 bond formation involves the CF3 acting as an electrophile with the Aryl ligand serving as a nucleophilic coupling partner. These mechanistic considerations along with DFT calculations have facilitated the design of a second generation system utilizing the tmeda (N,N,N′,...
Prospects for Upgrade of KEKB

The Belle experiment at the KEKB electron-positron collider is expected to have collected close to one billion ϒ ( 4 S ) events by the time it comes to an end in 2009. An upgrade to KEKB has been proposed. It is designed for an order of magnitude higher luminosity than KEKB, following a three-year construction period. The ultimate goal of 8 × 10 35 cm − 2 s − 1 luminosity would be reached through further improvements over several years. To exploit the physics accessible through this improved luminosity, an upgrade of the Belle detector is also planned. A new international collaboration, temporarily named sBelle, is in the process of being formed. Super-KEKB and sBelle were officially placed on the KEK 5-year Roadmap in early 2008.
Dielectric response of a planar periodic array of polarizable wires parallel to an interface with a nonlocal dynamic plasma-like medium

Abstract We examine the spatially inhomogeneous polarizability and dielectric function of the combined Coulomb-coupled system of a periodic lateral lattice array of polarizable 1D wire plasmas and a semi-infinite bulk plasma nearby. Furthermore, we carry out an exact closed form analytic solution of the spatially inhomogeneous random phase approximation integral equation for the dynamic nonlocal screening function, K ( r → , t ; r → ′ , t ′ ) , which is the space–time matrix inverse of the inhomogeneous dielectric function e ( r → , t ; r → ′ , t ′ ) , in the sense ∫ d 3 x d τ K ( r → , t ; x → , τ ) e ( x → , τ ; r → ′ , t ′ ) = δ 3 ( r → − r → ′ ) δ ( t − t ′ ) . In this Letter we also determine the exact dispersion relation coupling the periodic wire lattice plasmons with the semi-infinite bulk plasmon, and the residues of the screening function at the coupled mode frequencies provide the relative excitation amplitudes (oscillator strengths) of the various plasmon roots that emerge.
Phi meson production in relativistic heavy ion collisions

Abstract Within a multiphase transport model we study phi meson production in relativistic heavy ion collisions from both superposition of initial multiple proton–proton interactions and the secondary collisions in the produced hadronic matter. The yield of phi mesons is then reconstructed from their decaying product of either the kaon–antikaon pairs or the dimuon pairs. Since the kaon–antikaon pairs at midrapidity with low transverse momenta are predominantly rescattered or absorbed in the hadronic medium, they cannot be used to reconstruct the phi meson and lead thus to a smaller reconstructed phi meson yield than that reconstructed from the dimuon channel. With in-medium mass modifications of kaons and φ mesons, the φ yield from dimuons is further enhanced compared to that from the kaon–antikaon pairs. The model result is compared with the experimental data at the CERN/SPS and RHIC energies and its implications to quark–gluon plasma formation are discussed.
Hybrid Analysis of Gas Annular Seals With Energy Equation

Annular seals are used in turbomachinery to reduce secondary flow between regions of high and low pressure. In a vibrating rotor system, the non-axisymmetric pressure field developed in the small clearance between the rotor and the seal generate reactionary forces that can affect the stability of the entire rotor system.Traditionally, two analyses have been used to study the fluid flow in seals, bulk-flow analysis and computational fluid dynamics (CFD). Bulk-flow methods are computational inexpensive, but solve simplified equations that rely on empirically derived coefficients and are moderately accurate. CFD analyses generally provide more accurate results than bulk-flow codes, but solution time can vary between days and weeks. For gas damper seals, these analyses have been developed with the assumption that the flow can be treated as isothermal. Some experimental studies show that the difference between the inlet and outlet temperature temperatures is less than 5% but initial CFD studies show that there can be a significant temperature change which can have an effect on the density field. Thus, a comprehensive analysis requires the solution of an energy equation.Recently, a new hybrid method that employs a CFD analysis for the base state, unperturbed flow and a bulk-flow analysis for the first order, perturbed flow has been developed. This method has shown to compare well with full CFD analysis and experimental data while being computationally efficient. In this study, the previously developed hybrid method is extended to include the effects of non-isothermal flow. The hybrid method with energy equation is then compared with the isothermal hybrid method and experimental data for several test cases of hole-pattern seals and the importance of the use of energy equation is studied.Copyright © 2013 by ASME
In Situ Surface and Reaction Probe Studies with Model Nanoparticle Catalysts

This review paper discusses the in situ surface characterization and catalytic measurements of colloidally synthesized model metal nanoparticle (NP) catalysts studied in the Somorjai lab. Sum Frequency Generation (SFG) vibrational spectroscopy technique revealed the vibrational signatures of binding geometry and surface orientation of adsorbate molecules by probing the immediate surface structure during the catalytic reactions. Metal surfaces were studied by Synchrotron-based spectroscopic techniques at the Advanced Light Source in the Lawrence Berkeley National Laboratory. Ambient Pressure X-ray Photoelectron Spectroscopy (APXPS) was employed to measure chemical and elemental structure of bimetallic NP catalysts under the catalytically relevant pressures in the Torr range. Surface chemical structure (i.e., oxidation states) of metals was obtained by X-ray Absorption Fine Structure Spectroscopy by constructing a gas flow cell that operates under atmospheric pressures as the reaction occurs. Environmental ...
Errors in variables in simultaneous equation models

Abstract The simultaneous equation model is considered when errors in variables are present in the exogenous variables. By means of a distributional assumption on the exogenous variables, the system is transformed into an augmented structural model. Full information estimation by means of maximum-likelihood and instrumental variables is proposed. Depending on the assumptions on the errors of observation, restrictions may be imposed on the covariance matrix of the augmented structural residuals.
Inhibitors and Antagonists of Bacterial Quorum Sensing

Bacteria can regulate community-wide behaviors including biofilm formation, virulence, conjugation, sporulation, and swarming motility through a process called quorum sensing. Inhibitors and antagonists of bacterial quorum sensing are important research tools and potential therapeutic agents. In this review, we have summarized recent developments in this area.
Radio Emission from Acceleration Sites of Solar Flares

This Letter takes up the question of what radio emission is produced by electrons at the very acceleration site of a solar flare. Specifically, we calculate incoherent radio emission produced within two competing acceleration models—stochastic acceleration by cascading MHD turbulence and regular acceleration in collapsing magnetic traps. Our analysis clearly demonstrates that radio emission from acceleration sites (1) has sufficiently strong intensity to be observed by currently available radio instruments, and (2) has spectra and light curves that are distinctly different in these two competing models, which makes them observationally distinguishable. In particular, we suggest that some of the narrowband microwave and decimeter continuum bursts may be a signature of the stochastic acceleration in solar flares.