Spectrophotometric studies of the photolysis of diazido-bis(phosphine)-metal(II) complexes

The photolysis of mixed ligand complexes of the type MLn(N3)2 (M=Ni, Pd, Pt; L = phosphane and diphosphane ligands, respectively; n = 1, 2) was monitored by electronic spectroscopy in absorption, emission and excitation. Initial quantum yields of these complexes were measured in CH2Cl2 and EtOH in dependence on the irradiation wavelength. Photochemically formed MOIn fragments of Pd and Pt are distinguished by an intensive emission detected at 77 K. No emission was observed with respect to the appropriate NiO fragments. An initial emission at 615 nm detected by irradiating Pd(PPh3)2(N3)2 at 77 K is explained by assuming a photochemical cis/trans isomerization Quenching experiments have been performed by using Ru(bpy)3Cl2, Os(bpy)3Cl2, Re(CO)3(phen)Cl and Cr(bpy)3(ClO4)3 as sensitizers and the mixed-ligand complexes under discussion as quenchers

ANALYSIS OF ACROBKIIC TUMBLING EXERCISES ON FLOOR AND BALANCE BEAM

INTRODUCTION - Acrobatic tumbling exercises on floor and balance beam belong to the movement structures which are decisive for performance. The most complicated somersault variants are mostly performed following preparing elements as rondat and flic-flac. Toperform the complicated somersaults well a big amount of kinetic energy has to be supplied by the run-up and by rondat as well as flic-flac at the onset of take-off for the somersault. The conditions for theenergy production and the solutions for itare analysed for both apparatuses. Differences between the two apparatuses are illustrated. The comparative studies were done as case study with the example of the tumbling set rondat, flic-flac, Tsukahara. The exercise was performed by female and male gymnasts on the floor and on the balance beam. Using 2D and 3D procedures to process images video recordings(50 fls) of the individual Gymnastics World Championships 1994 in Brisbane and World Team championships in gymnastics1994 in Dortmund were analysed. The body was separated into 10 segments. Kinetic energy, angular momentum on the transversal axis - in relation to the individual segments and the whole body - , horizontal speed of the centre of gravity, spatial as well as body angles served as main parameters. To gain parameters which can be compared energy and angular momentum were related to unified values concerning bodyheight and bodyweight. RESLILTS - Before the take-off for a complicated somersault variant kinetic energy preceding the take-off for a somersaults on the floor amounts about 1500Nm. The value is almost the same for female and male gymnasts. The higher driving height (difference of the centre of gravity between take-off and peak value of the air-borne movement) which male gymnasts perform is due to better strength abilities. The comparison between floor and balance beam exercises prove that the apparatus' conditions preceding the takeoff or a somersault on the floor produce a much bigger kinetic energy than on the balance beam. Thus we measured bigger driving heights on the floor and the reduction of the initial angular momentum in relation to the somersault angular momentum is more distinct. Energy can be produced during supporting phase of the feet and the hands in the flic-flac. CONCLUSION - The degree of difficulty of the elements performed on the balance beam can only be enhanced to a limited extend in relation to the floor. The height of the balance beam which causes a longer flight-time is only of subordinated importance. The increase in energy during the hand, supporting phase is often used to a little extend only. REFERENCES - WEBER, R. & KNOLL,K. (1989). Weltmeisterschaften im Kunstturnen1989. Wissenschaftlicher Bericht.Schwebebalken. In FEDERATION INTERNATIONALEDE GYMNASTIQUE (Hrsg.)Weltmeisterschaften im Kunstturnen Stuttgart1989. Wissenschaftlicher Bericht(S. 31-39). - THEISS, P. (1992). Aktuelle Entwicklungstendenzen akrobatischer Elemente auf dem Schwebebalken. In G.-P. BRiJGGEMANN & J. K. RLIHL (Hrsg.).Biomechanics in Gymnastics. First Int.Conference Cologne 8.-10.9.1992. Conference Proceedings (S. 129-1 37). Koln:Sport und Buch Strauss, Ed. Sport

THE KINEMATIC DYNAMIC STRUCTURE OF EFFECTIVE GIANT SWINGS BACKWARD PRIOR TO DIFFICULT DISMOUNTS AND FLIGHT ELEMENTS ON HORIZONTAL BAR AND UNEVEN BARS

The purpose of this study was to investigate into the kinematic dynamic structure of dismount giant swings backward executed effectively on horizontal bar and uneven bars. The functional dependence of angular momentum, vertical velocity and reaction force of the bar and their relation with the beat leg swing were demonstrated. A double peak in the force curve with physically determined intervals of the maximums is typical. The position of the 1st maximum, the so-called hang, determines the kind of dismount (before or over the bar) and the effectiveness of leg swing. On the uneven bars, a too late hang is a frequent mistake. A leg swing with only a low degree of efficiency and a small height in the dismount result from this. The learning time for difficult dismounts and flight elements can be shortened by feedback about the 1st force maximum in the dismount giant swing

"Of order and liberty" : Catholic intellectuals in Argentina and Brazil

textThis project challenges the historical binary of a revolutionary versus a reactionary Church through a comparative case study of right-wing Christian Democrats in Brazil and Integralist/Nationalist intellectuals in Argentina. Intellectually, the project centers on Jacques Maritain and notable Latin American figures. Such figures include Brazilians Alceu Amoroso Lima and Dom Hélder Câmara, and Argentine leaders Julio Meinvielle and Leonardo Castellani. The study will argue that these figures' intellectual stands represented diverging paths for each country's conservative majority, but also shaped their respective hierarchies' reactions to key events in the Catholic and secular world: the Spanish Civil War, World War II, the Second Vatican Council. While anti-Modernists, Brazilian intellectuals came to favor pluralist and democratic solutions of Social Democracy over and above the organic (and encompassing) visions espoused by Franco's Spain, and subsequently, the Argentine hierarchy. This study will analyze major Catholic newspapers and journals, including Criterio, Jauja , A Ordem, and O Diario de Belo Horioznte. These sources will give the reader a glimpse into the intellectual societies and forums in which these thinkers moved, and will more clearly display the distinction mentioned above. Surprisingly, conservative Brazilian papers maintained a vigorous anti-Communist stance, but came to see the government as an oppressing force prohibiting the legitimate social actions of the Catholic faithful. Argentine intellectuals took a much more ambivalent attitude toward democracy at best, and a more hostile one at worst. Julio Meinvielle and Leonardo Castellani from their journal Jauja directly challenged the Second Vatican Council, the liberal state, and the rights of left-wing dissidents. More generally, Argentine ties to Franco's Spain through the 1970s, as well as to conservative varieties of Peronism, as well as the loss of the unifying Gustavo Franceschi (editor of Criterio) in 1957, put the sizable democratic and reformist minority firmly outside the good graces of the hierarchy, paving the way for the Catholic purges in Argentina of the 1970s.Latin American Studie

Existential mental health implications for kin-caregivers of Alzheimer\u27s victims

The purpose of this paper is to briefly outline assessment and progression of Alzheimer\u27s disease (AD) in afflicted individuals (i.e., care recipients [CRs]) and review relevant research concerning the effects of AD progression on caregivers (CGs) as they care for loved ones. With this background, consideration will be made of how these findings suggest relevant tenets of Existential therapy. The author will also identify implications that could be meaningful to mental health professionals in their efforts to assist CGs as they attempt to cope with the emotional impact this disease has on them during caregiving and after the eventual death of the CR. The premise of this paper is that Existential Therapy (ET) is particularly well suited for this area of psychotherapy because of the salient issues involved and because ET concepts can be utilized within many psychotherapeutic approaches (Yalom, 1980)

Optimal operating conditions and characteristics of acetone/CaF_2 detector for inverse photoemission spectroscopy

Performance and characteristics of a band-pass photon detector using acetone gas and CaF_2 window (acetone/CaF_2) have been studied and compared with an ethanol/MgF_2 detector. The optimal operating conditions are found to be 4 mbar acetone pressure and 745+/-20 V anode voltage. The count rate obtained by us is about a factor of 3 higher than what has been reported earlier for the acetone detector. Unlike other gas filled detectors, this detector works in the proportional region with very small dead time (4 micro sec). A detector band-pass of 0.48+/-0.01 eV FWHM is obtained.Comment: Review of Scientific Instruments 76, 066102 (2005

ANGULAR MOMENTUM IN JUMPS WITH ROTATIONS ON THE LONGITUDINAL AXIS IN FIGURE SKATING -3D-ANALYSES AND COMPUTER SIMULATION

INTRODUCTION -In analyses of athletic technique in figure skating primarily jumps with tripie or four-time rotations on the longitudinal axis are considered The quality of these jumps is essentially influenced by vertical momentum and angular momentum. While vertical momentum can be obtained without problems from flight parameters the calculation of angular momentum does represent a much more complicated problem. The task is to optimise vertical and angular momentum and to answer the question for reasons causing that the longitudinal axis is tilted during flight. This is important since a slightly tilled position of this axis can cause a fall in figure skating. Analyses of errors therefore mostly concentrate on the identification of reasons for this tilted position during flight already in the take-off. Therefore 3D monitoring only is insufficient for recommendations on sports techniques but additional 3D calculations (e.g. calculation and three-dimensional presentation of angular momentum) have to be performed. METHODS -A procedure for a threedimensional presentation of angular momentum as vector is presented. Using this procedure reasons for errors can be determined and general orientations for sport technical models can be characterised. Another procedure offers the opportunity to quantify the partial contribution of individual parts of the body in producing angular momentum. To determine the efficient use of the produced angular momentum 3D computer simulation is applied RESULTS 1. The influence of the angle between longitudinal axis and direction of angular momentum on the efficient use of the produced angular momentum is determined as a result of computer simulation 2 The influence of movements of individual parts of the body on the production of the total angular momentum as a reason for tilting the longitudinal axis during flight is studied. 3. We study practical applications in sports practice to present conclusions for the training of sports technique We give recommendations for individual solutions concerning sports technique res. general models to optimise sports technique of the most complicated technical elements. Using the example of the triple Axel, the most complicated triple jump in figure skating, we present opportunities for an interpretation of our results in sports practice

Calculation forces from bar movement on parallel bars in gymnastics

Modern artistic gymnastics apparatus have elastic properties, which the gymnast should use. It is important to know how a gymnast can give energy to the apparatus, especially to the bar(s) and how the stored energy can be used by the gymnast. The parallel bars were not included in such questions in the research yet. A static calibration at different positions of one bar was utilized as a precondition for the calculation of the forces during gymnastics exercises. Using synchronized 2D-video-analysis of the bar movement and the gymnasts performance (2 cameras) we calculate the forces based on our calibration. Examples of force-time-curves from parallel bars dismounts from German national gymnastics team will be shown. Using force-time-characteristics for supporting motor learning is a difficult task for the future