[en] We have calculated the deflections of nearly monoenergetic atomic beams under resonant laser light pressure. These deflection experiments may be used to analyze the velocity distributions in atomic beams, to measure the lifetimes of excited states of atoms, and to verify the theory of photon statistics

[en] The road transport system is closely linked to the land-use system. The road system connects territories at all spatial scale, on the other hand, passengers and freight travel behavior are strongly influenced both by land-use and the road transport system. Hence, research in the field of the interactions between land-use and the road transport system is still less, particular the influence of the economic crisis. This paper aims to find out if the statistical analysis of land use and mobility can help to answer the question of what happens during economic crisis on both land use and transport system, and unveiling key spatial relationships between them. The methodology for the analysis was developed accordingly with the data and resources available. First, an exploratory data analysis (EDA) is performed in order to identify the land use and mobility pattern during the last decade. This analysis focuses on six aspects, which are distribution of population and dwellings, employment and jobs, GDP, motorization and modal split. The second aspect consists on crossing the spatial patterns of the different aspects in order to find some explanatory relationships that indicate the presence of the key characteristics. The analysis is based on the case of Madrid Region. The land-use and transport data presented in this analysis are from 2004 to 2014, which are collected from the national statistical institute, the regional government database and two urban mobility surveys of Madrid. Through the exploration analysis, we find that there is close relationship between the land-use system and travel behavior in Madrid Region. With an increasing of new dwellings constructed in the outer periphery of Madrid Region, it leads longer trips distance and more travel cost particularly by car mode. Moreover, during the economic crisis, we also find the motorization level of Madrid keeps the same, as a result of the decreasing GDP and relatively decreasing. (Author)

[en] X-rays at a minimal exposure level representing 25% of the conventional exposure are emitted from an X-ray tube and pass through a subject, such as a patient under-going radiographic examination. The minimal exposure X-rays are detected by a preselected detector means, such as illuminated film, an X-ray intensifier, a CT scanner, a radioactive nuclear scanner or an image intensifier in combination with a televeision camera. The detector converts the radiation emerging from the subject to light images in the case of the video system. The light images are converted to electronic signals in a television camera. In the case of the CT scanner and nuclear scanner a photodiode array or scintillation crystal is actuated by the emerging radiation to generate an electrical current proportional to the intensity of the emerging radiation. The electronic signal is transmitted to an analog to digital converter, and the digital signal is transmitted to a computer for storage. Simultaneously, the digital signal is processed by the computer in accordance with a mathematical model to convert the signal representing the minimal exposure level to a signal representing the maximum or conventional exposure level. Output from the computer representing the maximum exposure level is either suitably stored for later retrieval or the retrieval or the digital signals are converted to analog signals for transmission to a video display device. In this manner, a radiograph is obtained by exposing the subject to substantially less than the conventional radiation level and having the degree of spatial resolution normally obtained at the conventional radiation level

[en] Within the framework of plate tectonics, the deformation that arises from the relative movement of two plates occurs across discontinuities in the earth's crust, known as fault zones. Active fault zones are the causal locations of most earthquakes, which suddenly release tectonic stresses within a very short time. In return, fault zones slowly grow by accumulating slip due to such earthquakes by cumulated damage at their tips, and by branching or linking between pre-existing faults of various sizes. Over the last decades, a large amount of knowledge has been acquired concerning the overall phenomenology and mechanics of individual faults and earthquakes: A deep physical and mechanical understanding of the links and interactions between and among them is still missing, however. One of the main issues lies in our failure to always succeed in assigning an earthquake to its causative fault. Using approaches based in pattern-recognition theory, more insight into the relationship between earthquakes and fault structure can be gained by developing an automatic fault network reconstruction approach using high resolution earthquake data sets at largely different scales and by considering individual event uncertainties. This thesis introduces the Anisotropic Clustering of Location Uncertainty Distributions (ACLUD) method to reconstruct active fault networks on the basis of both earthquake locations and their estimated individual uncertainties. This method consists in fitting a given set of hypocenters with an increasing amount of finite planes until the residuals of the fit compare with location uncertainties. After a massive search through the large solution space of possible reconstructed fault networks, six different validation procedures are applied in order to select the corresponding best fault network. Two of the validation steps (cross-validation and Bayesian Information Criterion (BIC)) process the fit residuals, while the four others look for solutions that provide the best agreement with independently observed focal mechanisms. Tests on synthetic catalogues allow qualification of the performance of the fitting method and of the various validation procedures. The ACLUD method is able to provide solutions that are close to the expected ones, especially for the BIC and focal mechanism-based techniques. The clustering method complemented by the validation step based on focal mechanisms provides good solutions even in the presence of a significant spatial background seismicity rate. As the new clustering method is able to deal with most of the information contained in modern earthquake catalogues, the geometry of the local station network may improve or alter the reconstruction of the underlying fault system. This is illustrated by using the highest-quality data selected using station network criteria which results in reconstructed fault planes of higher quality and accuracy. Using lower-quality data can lead to unstable and unreliable fault networks and may introduce artefacts, in particular in regions of a complex fault structure. The results highlight the need to carefully assess the quality and reliability of reconstructed fault networks from real data that unavoidably involve the clustering of data of heterogeneous quality. Based on realistic tests with synthetic fault network structures, the results also stress the importance of accounting for under-sampled sub-fault structures as well as for spatially-inhomogeneous location uncertainties. The fault reconstruction method is applied to two real datasets at two very different spatial scales, i.e. the 1992 Landers M7 earthquake sequence in Southern California, and the Basel (Switzerland) induced seismicity sequence. In both case studies, fault network results reasonably compare with independent structural analysis data, suggesting highly complex fault structures for both, at the scale of the Landers earthquake covering a volume of about 70,000 km³ and in the volume of the Basel induced seismicity sequence contained in 1 km³. This complexity of reconstructed fault network implies that the application of automatic network reconstruction methods may, in the future, be added in order to better forecast the spatial distribution of earthquakes within such sequences

[en] Cross sections of charge transfer and electron detachment in collisions of H^- and D^- with Na, K, and Cs were measured for collision energies ranging from 3 to 300 eV. Both charge transfer and electron detachment are significant electron-loss mechanisms for H^- (D^-); both processes exhibit velocity-dependent isotope effects for H^- and D^-. σ/sub cg/(E) displays high energetic thresholds for Na and K (about 20 eV for H^- + Na and 40 eV for H^- + K), yet no obvious one for Cs. σ/sub c/(E) does not depend on the target as much as σ/sub ct/(E) and displays near zero-energy thresholds. The relative importance of charge transfer as an electron-loss mechanism decreases as the mass of the alkali-metal increases

[en] Assimilation of lidar observations for air quality modelling is investigated via the development of a new model, which assimilates ground-based lidar network measurements using optimal interpolation (OI) in a chemistry transport model. First, a tool for assimilating PM₁₀ (particulate matter with a diameter lower than 10 μm) concentration measurements on the vertical is developed in the air quality modelling platform POLYPHEMUS. It is applied to western Europe for one month from 15 July to 15 August 2001 to investigate the potential impact of future ground-based lidar networks on analysis and short-term forecasts (the description of the future) of PM₁₀. The efficiency of assimilating lidar network measurements is compared to the efficiency of assimilating concentration measurements from the AirBase ground network, which includes about 500 stations in western Europe. A sensitivity study on the number and location of required lidars is also performed to help define an optimal lidar network for PM₁₀ forecasts. Secondly, a new model for simulating normalised lidar signals (PR₂) is developed and integrated in POLYPHEMUS. Simulated lidar signals are compared to hourly ground-based mobile and in-situ lidar observations performed during the MEGAPOLI (Mega-cities: Emissions, urban, regional and Global Atmospheric Pollution and climate effects, and Integrated tools for assessment and mitigation) summer experiment in July 2009. It is found that the model correctly reproduces the vertical distribution of aerosol optical properties and their temporal variability. Additionally, two new algorithms for assimilating lidar signals are presented and evaluated during MEGAPOLI. The aerosol simulations without and with lidar data assimilation are evaluated using the AIRPARIF (a regional operational network in charge of air quality survey around the Paris area) database to demonstrate the feasibility and the usefulness of assimilating lidar profiles for aerosol forecasts. Finally, POLYPHEMUS with the model for assimilating lidar signals is applied to the Mediterranean basin, where 9 ground-based lidar stations from the ACTRIS/EARLINET network and 1 lidar station in Corsica performed a 72-hour period of intensive and continuous measurements in July 2012. Several parameters of the assimilation system are also studied to better estimate the spatial and temporal influence of the assimilation of lidar signals on aerosol forecasts. (author)

[en] The formation mechanism of three arylcarbenium ions, the benzyl cation, the benzhydryl cation, and the trityl cation, in the irradiated 1,2-dichloroethane solution was studied. It was found that two kinetically distinguishable positive charged species were formed by the radiolysis of 1,2-dichloroethane. One is believed to be a parent radical cation or a radical cation resulting from the HCl elimination or both (if they are kinetically indistinguishable); the other is believed to be a chloronium ion resulting from the cleavage of C-Cl bond. Different precursor compounds selectively scavenge these two species and yield different carbenium ions. The reactivities of the benzyl and the benzhydryl cations with various alkenes were determined. The second order rate constants range from 8.7 x 10⁵ M^-1 sec^-1, to 1.0 x 10⁹ M^-1 sec^-1. Such data are valuable for the study of cationic vinyl polymerization reactions. The structural effects on reactivity for this type of reaction was also investigated. It was found that two generalizations, the product stability principle and the principle of least nuclear motion, may qualitatively explain the observed effects

[en] The effect on solidification microstructure of Al-3wt%Fe produced by addition of either 1.0wt% or 0.1wt% Cu, Mg, Si or 0.01 to 0.1wt% V has been determined by means of wedge chill casting, direct chill simulation casting and Bridgman growth over the range of solidification front velocity between 0.033 to 1.03mm/s during steady state growth with an temperature gradient of 8 to 18K/mm. Coupled eutectic growth has been investigated and the effect of the further additions on the eutectics and their transitions have been determined by constant velocity Bridgman growth (CBG) and by accelerating Bridgman growth (ABG) with accelerations 3.61 x 10^-4, 1.11 x 10^-3 and 1.86 x 10^-3mm/s² over the velocity ranges 0.033 to 0.33mm/s, 0.33 to 0.67mm/s, and 0.67 to 1.0mm/s, respectively. Growth competition was found to be between primary αAl dendrites, primary Al₃Fe intermetallic and five eutectics, i.e. αAl-Al₃Fe (Eu1), αAl-Al₆Fe (Eu2), αAl-AI_mFe (Eu3), αAl-αAlFeSi (Eu4) and αAl-Al_xFe (Eu5), for the alloys and ranges of solidification front velocity and temperature gradient in the present work. With an acceleration of 3.61 x 10^-4mm/s², ABG revealed that, for binary Al-3wt% Fe, Eu1 was suddenly replaced by Eu2 at V≥0.10mm/s. Cu addition favoured eutectic Al₆Fe over primary Al₃Fe whilst Mg promoted growth of both primary Al₃Fe and Eu1 to higher velocity, with 0.60 and 0.33 mm/s being required in Al-2.84Fe-1.11 Mg for suppression of primary Al₃Fe and replacement of Eu1 with Eu2, respectively. Crystallographic faceting of eutectic Al₆Fe crystals was observed in Al-2.84Fe-1.11Mg alloy with the facet planes being determined to be {110}. Si addition resulted in formation of cubic αAlFeSi phase in both DC simulation cast and Bridgman grown samples, with the critical velocity for the transition from Eu1 to Eu4 being determined to be 0.091mm/s (CBG) or 0.2mm/s (ABG). Vanadium addition, however, introduced Eu5 with fully Eu5 structure being obtained from 0.071 to 1.03mm/s, 0.34 to 1.03mm/s and 0.20 to 0.34mm/s in Al-2.5Fe-0.12V, Al-3.09Fe-0.044V and Al-3.15Fe-0.006V, respectively. Eu5 in the Al-2.85Fe-0.12V and Al-3.09Fe-0.044V alloys showed a morphological transition from lamellar to rod-like with increasing growth velocity. The dependence of Eu5 eutectic interphase spacing λ on growth velocity V was found to follow the theoretically predicted relationship, λ√V=A, with A=22.4±1.8 or 13.8±2.1μm^3/2s^-1/2 for lamellar and rod-like growth, respectively. The observed ratio λ_lam/λ_rod =1.6 for fixed growth velocity V is close to the applicable value 1.55 predicted by the Magnin and Trivedi modification of the Jackson and Hunt model of eutectic growth. Growth temperature T_G of Eu5 at a temperature gradient G ranging from 8 to 18K/mm in the Al-2.85Fe-0.12V alloy conformed to the relationship, ΔT_EU = T_EU - T_G = B√V, with eutectic temperature T_EU = 649.0±1.0 deg. C and constant B = 0.32±0.04 Ks^1/2/μm^1/2. (author)

[en] This research involves a numerical study of the hydrodynamics of gas fluidized beds. The continuum model is used, treating both gas and particles as interpenetrating continua. The motion of gas and particles is strongly coupled by the interactions between them. For simplicity, only drag forces are considered. The author used MacCormack's numerical method to solve the hyperbolic-like equations and the successive-error vector-propagation method or a marching tridiagonal method to solve the elliptic equation for pressure, depending on the situation considered (i.e., boundary conditions and geometry). In order to understand the basic phenomena, the propagation of a finite disturbance of sine-wave shape in one dimension is considered. The disturbance grows in amplitude and forms a voidage shock. Next, the two-dimensional case is analyzed, starting from the uniform fluidization conditions. Also considered is the two-dimensional case with a rectangular obstacle. The initial condition is calculated using D'Arcy's law. Particle packing on the top and the local-expansion phenomenon under the obstacle are observed, as well as the interaction of a rising bubble. These numerical results agree qualitatively with experimental observations reported by others

[en] The work described was aimed at comparing the liver isozymes of glycogen synthase in terms of primary structure and phosphorylation patterns, with the better studied muscle counterpart. Rat liver glycogen synthase was purified to apparent homogeneity. It was subjected to multiple phosphorylation by eight protein kinases. Phosphorylation sites were distributed between two CNBr-fragments, CB-1 (14,000) and CB-2 (28,000). Amino acid sequences of phosphopeptides of rabbit liver glycogen synthases modified by cyclic AMP-dependent protein kinase were determined and three phosphorylation sites were identified. A simple and effective procedure for determining the location of phosphorylation sites in phosphopeptides was also developed. The method employed measurement of [³²P]inorganic phosphate release during Edman degradation cycles using the gas phase sequencer. Comparison of the liver and muscle isozymes has shown that similarities are more prominent than differences and isozymes share several important properties in multiple phosphorylation and hormonal regulation