Analytical And Experimental Aeroacoustic Studies Of Open-Ended 3-Duct Perforated Elements Used In Mufflers

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Non-bonded interactions in 2,2,4,4-tetramethyl-1,3-cyclobutanedithione and 2,2,4,4-tetramethyl-3-thio-1,3-cyclobutanedione

Electronic absorption and emission spectra as well as He(I) photoelectron spectra of 2,2,4,4-tetramethyl-,3-cyclobutanedithione and 2,2,4,4-tetramethyl-1-3-thio-1,3-cyclobutanedione have been interpreted on the basis of molecular orbital calculations. The results show that the non-bonded orbital of the dithione is split owing to through-bond interaction, the magnitude of splitting being 0.4 eV. The π* orbital of the dithione appears to be split by about 0.2 eV. Electronic absorption spectra show evidence for the existence of four n—π* transitions, arising out of the splitting of the orbitals referred to above, just as in the case of 2,2,4,4-tetramethyl-1,3-cyclobutanedione. Electronic and photoelectron spectra of the thio-dione show evidence for weak interaction between the C=S and C&.zdbnd;O groups, probably via π* orbitals. Infrared spectra of both the dithione and the thio-dione are consistent with the planar cyclobutane ring; the ring-puckering frequency responsible for non-bonded interactions is around 67 cm−1 in both the dithione and the thio-dione, the value not being very different from that in the dione. The 1,3-transannular distance is also similar in the three molecules.

3 - 5-vuotiaiden lukemaan oppiminen : montessorivälineet kielellisen tietoisuuden ja varhaisen lukitaidon edistäjinä

Aims. The beginning point of this research was confusion between studies claiming, that children mature Metalinguistic to read at 6-7 of age, and the fact, that in Montessori playschools children easily start writing and reading at age 3 to 5. Aim was also find out how conception of slow Metalinguistic development has started, and if there is some evidence of phoneme awareness of reading of young children in the field of research of reading. Aim was also seek evidence of the sensitive period of reading as Montessori described it. The research also wanted to turn up, if phoneme awareness only develops in children, who work with graphemes and with reading, or could it be found in children, who do not. The mean was to research how the Montessori reading material supports child’s Metalinguistic development, when child begins learning to read. The research plans to represent knowledge about how young children learn to write and read. Methods. Research performed in ordinary kindergarten and in Montessori playschool in Espoo. In kindergarten observed six children, age 3-4, at eight grapheme-rhyme sessions from January to April 2007, and conducting a test based on Chaney’s (1992) study of phoneme awareness of young children. In Montessori kindergarten were observed 17 children about their phoneme awareness and reading competition from January 2007 to March 2008. Their developments in reading were also measured three times from 1.9.07 to 20.3.08 with classification constructed for this study, loosely based on Chall’s (1983) reading stages. The Montessori reading material was analyzed about the influence they have to a child’s Metalinguistic development. This was done based to theory and its concepts from the field of research of reading; phoneme awareness, morphological, syntactical and semantic consciousness. Results and conclusions. Research proved that children 3-5 have naturally developed phoneme awareness. In kindergarten and in Montessori playschool children between 2 and 4 could do phoneme synthesis, and in the latter they also could do phoneme segmentation of words. Montessori reading material guided children gradually, except to read, also to observe and absorb Metalinguistic knowledge. Children learned to write and read. At the last evaluating day almost 50 % of children write and read clauses or stories, and 82 % could read at least words. Children can develop Metalinguistic awareness, while using the Montessori materials for learning to write and read. To reach literacy is easy for children because of their phoneme awareness.

An investigation of bond formation in the weakly bound first excited 1Σ and lowest 3Σ states of HeH+

The role of the electronic kinetic energy and its Cartesian components is examined during the formation of the first excited 1�£ and the lowest 3�£ states of HeH+ employing wavefunctions of multi-configuration type with basis orbitals in elliptic coordinates. Results show that the bond formation in these states is preceded primarily by a charge transfer from H to He+ rather than by polarisation of the H-orbital by He+

Editorial of "International Journal of Critical Indigenous Studies Volume 3, Number 2, 2010"

In this of the International Journal of Critical Indigenous Studies, the articles reveal how competing economies of knowledge, capital and values are operationalised through colonising power within inter-subjective relations. Writing in the Australian context, Greg Blyton demonstrates how tobacco was used by colonists as a means of control and exchange in their relations with Indigenous people. He focuses on the Hunter region of New South Wales, Australia, in the early to mid-nineteenth century to reveal how colonists exchanged tobacco for food, safe passage and Indigenous services. Blyton suggests that these colonial practices enabled tobacco addiction to spread throughout the region, passing from one generation of Indigenous people to another. He asks us to consider the link between the colonial generation of Indigenous tobacco consumption and addiction, and Indigenous mortality rates today whereby twenty percent of deaths are attributed to smoking.

Christianity and Christian Identity in the Gospel of Philip (NHC II,3)

Previous scholarship has often maintained that the Gospel of Philip is a collection of Valentinian teachings. In the present study, however, the text is read as a whole and placed into a broader context by searching for parallels from other early Christian texts. Although the Valentinian Christian identity of the Gospel of Philip is not questioned, it is read alongside those texts traditionally labelled as "mainstream Christian". It is obvious from the account of Irenaeus that the boundaries between the Valentinians and other Christians were not as clear or fixed as he probably would have hoped. This study analyzes the Valentinian Christian Gospel of Philip from two points of view: how the text constructs the Christian identity and what kind of Christianity it exemplifies. Firstly, it is observed how the author of the Gospel of Philip places himself and his Christian readers among the early Christianities of the period by emphasizing the common history and Christian features but building especially on particular texts and traditions. Secondly, it is noted how the Christian nature of an individual develops according to the Gospel of Philip. The identity of an individual is built and strengthened through rituals, experiences and teaching. Thirdly, the categorizations, attributes, beliefs and behaviour associated on the one hand with the "insiders", the true Christians, and, on the other, with outsiders in the Gospel of Philip, are analyzed using social identity theory the insiders and outsiders are described through stereotyping in the text. Overall, the study implies that the Gospel of Philip strongly emphasizes spiritual progress and transformation. Rather than depicting the Valentinians as the perfect Christians, it underlines their need for constant change and improvement. Although the author seeks to clearly distinguish the insiders from the outsiders, the boundaries of the categories are in fact fluid in the Gospel of Philip. Outsiders can become insiders and the insiders are also in danger of falling out again.

Computer simulation of H and He effects in fusion reactor materials

Fusion power is an appealing source of clean and abundant energy. The radiation resistance of reactor materials is one of the greatest obstacles on the path towards commercial fusion power. These materials are subject to a harsh radiation environment, and cannot fail mechanically or contaminate the fusion plasma. Moreover, for a power plant to be economically viable, the reactor materials must withstand long operation times, with little maintenance. The fusion reactor materials will contain hydrogen and helium, due to deposition from the plasma and nuclear reactions because of energetic neutron irradiation. The first wall divertor materials, carbon and tungsten in existing and planned test reactors, will be subject to intense bombardment of low energy deuterium and helium, which erodes and modifies the surface. All reactor materials, including the structural steel, will suffer irradiation of high energy neutrons, causing displacement cascade damage. Molecular dynamics simulation is a valuable tool for studying irradiation phenomena, such as surface bombardment and the onset of primary damage due to displacement cascades. The governing mechanisms are on the atomic level, and hence not easily studied experimentally. In order to model materials, interatomic potentials are needed to describe the interaction between the atoms. In this thesis, new interatomic potentials were developed for the tungsten-carbon-hydrogen system and for iron-helium and chromium-helium. Thus, the study of previously inaccessible systems was made possible, in particular the effect of H and He on radiation damage. The potentials were based on experimental and ab initio data from the literature, as well as density-functional theory calculations performed in this work. As a model for ferritic steel, iron-chromium with 10% Cr was studied. The difference between Fe and FeCr was shown to be negligible for threshold displacement energies. The properties of small He and He-vacancy clusters in Fe and FeCr were also investigated. The clusters were found to be more mobile and dissociate more rapidly than previously assumed, and the effect of Cr was small. The primary damage formed by displacement cascades was found to be heavily influenced by the presence of He, both in FeCr and W. Many important issues with fusion reactor materials remain poorly understood, and will require a huge effort by the international community. The development of potential models for new materials and the simulations performed in this thesis reveal many interesting features, but also serve as a platform for further studies.

Solvation and axial ligation properties of (2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetraphenylporphyrinato)zinc(II)

he solvation of (2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetraphenylporphyrinato)zinc(II)[Zn(obtpp)], in twelve different solvents results in large red shifts of the B and Q bands of the porphyrin accompanied by enhanced absorbance ratios of the Q bands. These observations are ascribed to the destabilisation of the highest occupied molecular orbital a2u of the porphyrin arising from a flow of charge from the axial ligand to the porphyrin ring through the zinc(II) ion. The binding constants of adducts of [Zn(obtpp)] with neutral bases have been found to be an order of magnitude greater than those observed for the corresponding adducts of (5,10,15,20-tetraphenylporphyrinato)-zinc and vary in the order piperidine > imidazole > pyridine > 3-methylpyridine > pyridine-3-carbaldehyde. The enhanced binding constants and large spectral shifts are interpreted in terms of the electrophilicity of [Zn(obtpp)] induced by the electron-withdrawing bromine substituents in the porphyrin core. The structure of [Zn(obtpp)(PrCN)2] has been determined; it reveals six-co-ordinated zinc(II) with two long Zn–N distance [2.51(4), 2.59(3)Å]. The porphyrin is non-planar and displays a saddle-shaped conformation.

3,12-dinitro-5,10,15,20-tetraphenylporphyrin- an example of a twisted intramolecular charge-transfer system

he porphyrin ring in the title compound, 10,19-dinitro-2,7,12,17-tetraphenyl-21,22,23,24-tetraazapenta-cyclo[16.2.1.1(3,6).1(8,11).1(13,16)]tetracosa-1,3,5,7,9,11(23),-12,14,16,18(21),19-undecaene 0.5-dichloromethane solvate, C44H28N6O4.0.5CH2Cl2, adopts a saddle conformation with neighbouring pyrrole rings tilted with respect to each other. The two nitro groups are situated on alternate pyrrole rings and have their planes angled away from those of the pyrrole rings, thereby indicating that interaction between the porphyrin and nitro groups is slight.

The unusual formation of methyl alpha-(5,6-dimethoxycarbonyl-2,3-dimethoxyazepin-7-ylidene)-alpha-[5-methoxycarbonyl-2,3-dimethoxypyrid-6-yl)acetate during the pyrolysis of ''azido-meta-hemipinate'' - First example of a reaction involving a concomitant ring expansion and ring extrusion

he ortho methoxycarbonyl substituent constitutes a sole exception in the ring closure reactions of ortho substituted aryl azides, as it provides no rate acceleration to this reaction. Pyrolysis of ''azido-meta-hemipinate'', an aryl azide containing such a substituent, led us to the title compound, a new azepinylidenepyridylacetic ester, whose structure has been established unambiguously by a single crystal X-ray diffraction study. This is the first report of a reaction involving both a ring expansion to an azaheptafulvalene and a ring extrusion to a pyridyl ring residue.

“¿No les corresponde conocer el derecho?” : estudio de Miqueas 3, 1-12

Resumen: El autor se propone estudiar desde una perspectiva literaria, crítica y retórica el capítulo 3 del profeta Miqueas. Para esto, en primer término plantea una estructura a partir de los oráculos de condena que el discurso posee. Luego intenta aproximarse al texto desde una perspectiva poético–literaria que intente explicar la fuerza discursiva de las figuras retóricas y del movimiento de la trama del texto. También se integra en el análisis la perspectiva teológica de las expresiones, sobre todo evaluando su alcance a partir de su relación con la tradición veterotestamentaria. Finalmente, se evalúa la intencionalidad del texto a partir de la composición redaccional y de lo que el análisis anterior fue brindando para poder imaginar un camino de actualización del mismo.

Synthetic scope and DFT analysis of the chiral binap-gold(I) complex-catalyzed 1,3-dipolar cycloaddition of azlactones with alkenes

he 1,3-dipolar cycloaddition between glycine-derived azlactones with maleimides is efficiently catalyzed by the dimeric chiral complex [(S-a)-Binap.AuTFA](2). The alanine-derived oxazolone only reacts with tert-butyl acrylate giving anomalous regiochemistry, which is explained and supported by Natural Resonance Theory and Nucleus Independent Chemical Shifts calculations. The origin of the high enantiodiscrimination observed with maleimides and tert-butyl acrylate is analyzed using DFT computed at M06/Lanl2dz//ONIOM(b3lyp/Lanl2dz:UFF) level. Several applications of these cycloadducts in the synthesis of new proline derivatives with a 2,5-trans-arrangement and in the preparation of complex fused polycyclic molecules are described.

Electro-optic integration of embedded electrodes and waveguides in LiNbO3 using a femtosecond laser

We describe the fabrication of a Mach-Zehnder optical modulator in LiNbO3 by femtosecond laser micormachining, which is composed of optical waveguides inscripted by a femtosecond laser and embedded microelectrodes subsequently using femtosecond laser ablation and selective electroless plating. A half-wave voltage close to 19 V is achieved at a wavelength of 632.8 nm with an interaction length of 2.6 mm. This simple and cost-effective technique opens up new opportunities for fabricating integrated electro-optic devices. (C) 2008 Optical Society of America

Observations of hydrogen and helium isotopes in solar cosmic rays

The isotopic composition of hydrogen and helium in solar cosmic rays provides a means of studying solar flare particle acceleration mechanisms since the enhanced relative abundance of rare isotopes, such as ²H, ³H and ³He, is due to their production by inelastic nuclear collisions in the solar atmosphere during the flare. In this work the Caltech Electron/Isotope Spectrometer on the IMP-7 spacecraft has been used to measure this isotopic composition. The response of the dE/dx-E particle telescope is discussed and alpha particle channeling in thin detectors is identified as an important background source affecting measurement of low values of (³He/⁴He).

The following flare-averaged results are obtained for the period, October, 1972 - November, 1973: (²H/¹H) = 7⁺¹⁰_-6 X 10^-6 (1.6 - 8.6 MeV/nuc), (³H/¹H) less than 3.4 x 10^-6 (1.2 - 6.8 MeV/nuc), (³He/⁴He) = (9 ± 4) x 10^-3, (³He/¹H) = (1.7 ± 0.7) x 10^-4 (3.1 - 15.0 MeV/nuc). The deuterium and tritium ratios are significantly lower than the same ratios at higher energies, suggesting that the deuterium and tritium spectra are harder than that of the protons. They are, however, consistent with the same thin target model relativistic path length of ~ 1 g/cm² (or equivalently ~ 0.3 g/cm² at 30 MeV/nuc) which is implied by the higher energy results. The ³He results, consistent with previous observations, would imply a path length at least 3 times as long, but the observations may be contaminated by small ³He rich solar events.

During 1973 three "³He rich events," containing much more ³He than ²H or ³H were observed on 14 February, 29 June and 5 September. Although the total production cross sections for ²H,³H and ³He are comparable, an upper limit to (²H/³He) and (³H/³He) was 0.053 (2.9-6.8 MeV/nuc), summing over the three events. This upper limit is marginally consistent with Ramaty and Kozlovsky's thick target model which accounts for such events by the nuclear reaction kinematics and directional properties of the flare acceleration process. The 5 September event was particularly significant in that much more ³He was observed than ⁴He and the fluxes of ³He and ¹H were about equal. The range of (³He/⁴He) for such events reported to date is 0.2 to ~ 6 while (³He/¹H) extends from 10^-3 to ~ 1. The role of backscattered and mirroring protons and alphas in accounting for such variations is discussed.

A quantitative investigation of the solar modulation of cosmic-ray protons and helium nuclei

The differential energy spectra of cosmic-ray protons and He nuclei have been measured at energies up to 315 MeV/nucleon using balloon- and satellite-borne instruments. These spectra are presented for solar quiet times for the years 1966 through 1970. The data analysis is verified by extensive accelerator calibrations of the detector systems and by calculations and measurements of the production of secondary protons in the atmosphere.

The spectra of protons and He nuclei in this energy range are dominated by the solar modulation of the local interstellar spectra. The transport equation governing this process includes as parameters the solar-wind velocity, V, and a diffusion coefficient, K(r,R), which is assumed to be a scalar function of heliocentric radius, r, and magnetic rigidity, R. The interstellar spectra, j_D, enter as boundary conditions on the solutions to the transport equation. Solutions to the transport equation have been calculated for a broad range of assumed values for K(r,R) and j_D and have been compared with the measured spectra.

It is found that the solutions may be characterized in terms of a dimensionless parameter, ψ(r,R) = ^∞∫_r V dr'/(K(r',R). The amount of modulation is roughly proportional to ψ. At high energies or far from the Sun, where the modulation is weak, the solution is determined primarily by the value of ψ (and the interstellar spectrum) and is not sensitive to the radial dependence of the diffusion coefficient. At low energies and for small r, where the effects of adiabatic deceleration are found to be large, the spectra are largely determined by the radial dependence of the diffusion coefficient and are not very sensitive to the magnitude of ψ or to the interstellar spectra. This lack of sensitivity to j_D implies that the shape of the spectra at Earth cannot be used to determine the interstellar intensities at low energies.

Values of ψ determined from electron data were used to calculate the spectra of protons and He nuclei near Earth. Interstellar spectra of the form j_D α (W - 0.25m)^-2.65 for both protons and He nuclei were found to yield the best fits to the measured spectra for these values of ψ, where W is the total energy and m is the rest energy. A simple model for the diffusion coefficient was used in which the radial and rigidity dependence are separable and K is independent of radius inside a modulation region which has a boundary at a distance D. Good agreement was found between the measured and calculated spectra for the years 1965 through 1968, using typical boundary distances of 2.7 and 6.1 A.U. The proton spectra observed in 1969 and 1970 were flatter than in previous years. This flattening could be explained in part by an increase in D, but also seemed to require that a noticeable fraction of the observed protons at energies as high at 50 to 100 MeV be attributed to quiet-time solar emission. The turnup in the spectra at low energies observed in all years was also attributed to solar emission. The diffusion coefficient used to fit the 1965 spectra is in reasonable agreement with that determined from the power spectra of the interplanetary magnetic field (Jokipii and Coleman, 1968). We find a factor of roughly 3 increase in ψ from 1965 to 1970, corresponding to the roughly order of magnitude decrease in the proton intensity at 250 MeV. The change in ψ might be attributed to a decrease in the diffusion coefficient, or, if the diffusion coefficient is essentially unchanged over that period (Mathews et al., 1971), might be attributed to an increase in the boundary distance, D.