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Recent studies of heavy ion transfer reactions using large solid angle spectrometers

Recent studies of heavy ion transfer reactions using large solid angle spectrometers

In order to employ multinucleon transfer reactions for studying both the production of neutron rich nuclei and the effects of the residual interaction, one needs to reach good mass and charge resolution, as well as high efficiency to measure low cross sections for massive transfer chan- nels. All these demanding requirements are fulfilled by large solid angle spectrometers based on trajectory recon- struction [6–8]. The coupling of these spectrometers with large γ arrays [9–11] allowed, in addition, to identify γ rays coming from the decay of weak transfer channels as- sociated with the population of nuclei moderately far from stability.
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New Products and Projects

New Products and Projects

r Market leadership in EDX detectors for microanalysis due to the excellent quality of our Silicon Drift Detectors (SDDs with integrated FET, large solid angle, best energy resolution, optimum light element performance and high throughput capacity).

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Photoproduction of Mesons on Quasi–Free Nucleons

Photoproduction of Mesons on Quasi–Free Nucleons

The modern experiments worldwide are using virtual or real photon beams and measure neutral and/or charged reaction products. The large solid-angle electromagnetic calorimeters, Crystal Ball/TAPS at MAMI (Mainz) and Crystal Barrel/TAPS at ELSA (Bonn) use real tagged-photon beams, the mag- netic CLAS spectrometer used also mostly tagged photons (partly also electron scattering), and the A1 collaboration at MAMI concentrates completely on electron scattering. Unfortunately, the nonex- istence of free neutrons requires the use of quasi-free neutrons as targets (bound in the deuteron or the other light nuclei). Despite the great e ff orts the physical parameters of many well established states remain uncertain. Moreover, the existence of strong isospin dependence of the electromagnetic transition amplitudes can only be studied with meson photoproduction o ff the neutron. The final goal of this activities is to collect (almost) complete data sets, allowing Partial-Wave Analysis (PWA) and the extraction of nucleon resonance properties without model dependent ambiguities.
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Magnetic flux transport simulations : applications to solar and stellar magnetic fields

Magnetic flux transport simulations : applications to solar and stellar magnetic fields

latitude at the beginning of the solar cycle, and emerge closer to the equator later on in the solar cycle. This plot also shows how we emerge approximately the same number of bipoles in both hemispheres of our simulation. Graph (b) shows a plot of the number of bipoles emerging every 27 days vs time. It can clearly be seen that, as the cycle progresses to solar maximum more bipoles emerge, which is the characteristic used to define this. As the cycle goes through the declining phase, the number of bipoles emerged gradually drops until solar minimum. Graph (c) shows a plot of the total flux from the emerging bipoles vs time, and this follows a similar pattern to graph (b). As more bipoles emerge in the rising phase, more flux will be available from them. As the numbers of bipoles begins to drop during the declining phase, the amount of flux that comes from the bipoles will also drop. Graph (d) shows the average monthly tilt angle of the bipoles, while graph (e) shows the distribution of tilt angles throughout the solar cycle. Graphs (d) and (e) show that at the start of the solar cycle, the average tilt angle of the bipoles can be seen to be larger than at the end of the cycle, with a fairly steady decline in tilt throughout the solar cycle as the bipoles begin to emerge at lower latitude. Graph (f) shows the average tilt angle vs latitude of emergence. As bipoles emerge at a higher latitude of emergence, they have a higher tilt angle. The graph seems to show the much shallower variation as suggested by Sch¨ussler & Baumann (2006) of tilt angle of the emerging bipoles versus latitude of approximately λ 5 . This is different from the previously calculated value of λ 2 found in Mackay et al. (2002) and Mackay & Lockwood (2002).
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Viable production mechanism of keV sterile neutrino with large mixing angle

Viable production mechanism of keV sterile neutrino with large mixing angle

are both indicated by colour. Green curves on top of the plots represent the direct constraints from ground-based experiments [4–6]. Two solid white lines depict projected sensitivity of Troitsk ν-mass after two stages of up- grade [18]. Inclined dashed black lines show the reference seesaw values (8) for active neutrino masses between 0.2 eV and 0.009 eV. Black solid line on both plots corresponds to non-resonant production of Ω N = Ω DM . In

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Retrieval of cirrus optical thickness and assessment of ice crystal shape from ground-based imaging spectrometry

Retrieval of cirrus optical thickness and assessment of ice crystal shape from ground-based imaging spectrometry

One way to check the retrieval algorithms with respect to horizontal cloud heterogeneity, spatial resolution and crys- tal shape is provided by flying airborne versions of spectro- radiometers above cirrus clouds, such as the MODIS Air- borne Simulator (MAS). With extensive microphysical and solar radiation instruments as well as radiative transfer simu- lations, Schmidt et al. (2007) and Eichler et al. (2009) inves- tigated the differences between retrieved and measured mi- crophysical cloud properties. Schmidt et al. (2007) revealed large gaps between the retrieved effective radius from MAS and simultaneous in situ measurements. This disagreement has not been resolved yet, partly because it has been ex- tremely difficult to collocate remote sensing above the clouds and concurrent in-cloud microphysical measurements. Such experiments are extremely important to link satellite cloud observations of coarse resolution to spatially highly resolved measurements of cloud properties. Unfortunately, such ex- periments are rare, partly because instruments like MAS are very complex and expensive and are not available for fre- quent cloud experiments.
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Research on Robot Welding in the Production of EMU Bogie Frame

Research on Robot Welding in the Production of EMU Bogie Frame

As shown in Figure. 4, the flat weld of the cross beam is the same as that of the side beam outer body weld. The vertical weld seam is the joint weld between the seat and the beam steel tube. The welding gun angle needs to be adjusted at any time during the welding operation. The accessibility of the welding operation is not easy to guarantee. Therefore, the welding operation of the vertical welding seam of the beam is difficult, and the quality of the manual welding is not easy to guarantee. At the same time, the angle of the weld joint between each seat and the beam steel tube is large, the welding amount is large, the manual operation intensity is large, and the cross beam vertical welding is suitable for robot welding.
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Astroblastoma: Radiologic Pathologic Correlation and Distinction from Ependymoma

Astroblastoma: Radiologic Pathologic Correlation and Distinction from Ependymoma

CT and MR imaging depict astroblastomas as dis- tinct from many of the other peripherally based tu- mors. Anaplastic astrocytomas and glioblastoma mul- tiforme may have a cystic appearance, but this appearance is caused by central necrosis. Notable peritumoral T2 hyperintensity is usually associated with these tumors. Oligodendrogliomas are rare tu- mors that usually start in the white matter and invade the cortex; they may be large and have foci of cystic degeneration that may appear bubbly. However, nod- ular or clumped calcifications are present in 70–90% of oligodendrogliomas, in distinction to the punctate calcifications seen in astroblastoma. Pleomorphic xanthoastrocytoma, ganglion cell tumors, dysembryo- plastic neuroepithelial tumor, rare supratentorial ju- venile pilocytic astrocytomas, and rare supratentorial hemangioblastomas all generally present with a strongly enhancing mural nodule within a single large cyst. Finally, metastases and lymphoma are more solid masses that have a larger amount of peritumoral T2 hyperintensity for tumor size than that of astro- blastoma.
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Research on Torque Angle Characteristic of Large Gap Magnetic Drive System

Research on Torque Angle Characteristic of Large Gap Magnetic Drive System

[8] J. P. Tan, Y. Xu, T. X. Li, and Y. L. Liu, “The scheme design and application of large gap magnetic drive system which is driven by traveling wave magnetic field,” IEEE International Conference on Measuring Technology and Mechatronics Automation (ICMTMA’09), Zhangjiajie, China, April 2009.

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Longer range distances by spinning angle encoding solid state NMR spectroscopy

Longer range distances by spinning angle encoding solid state NMR spectroscopy

acquisition of the free-induction decay, so as to obtain optimum sensitivity. The retention of both ideal resolution and long-range distance sensitivity was achieved by redesigning a 600 MHz HX MAS NMR probe to provide fast angle switching during the NMR experiment: For 1.8 mm rotors, angle changes of up to ~5 degrees in ~10 ms were achieved at 12 kHz MAS. A new experimental design that combines a reference and a dipolar-modulated experiment and a master-curve approach to data interpretation is presented.

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A Preliminary Discussion of the Polynomial Fits to the Thermal Curves of Solid-Solid Reactions, Carried Out in Bulk

A Preliminary Discussion of the Polynomial Fits to the Thermal Curves of Solid-Solid Reactions, Carried Out in Bulk

obtained experimental thermal curves of solid-solid reactions, carried out in bulk. The thermal curve for any solid-solid system is obtained by taking the chemicals of high purity, after separately grounding them well, in the desired ratio, in a test tube (2 cm inner diameter and 15cm length). The tube is immediately placed in a Dewar flask and a sensor stick and a stop watch started at the time of mixing. The readings of temperature are recorded at every 30 second interval of time, by the digital electronic ther mometer, with accuracy of 0.01°C. The temperature readings for a system are taken for one hour. To ensure that the room temperature is constant measurements are done in AC chamber. We plot the graph of temperature rise (in degree Celsius) vs. time (in minutes). Clearly, all those studies are carried out at the room temperature. We have also done the thermal measurements after mixing different inorganic solid, organic solid as well as organic solvent impurities to the pure reactants. We have obtained the thermal curves. We have
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Symmetry based pulse sequences in magic angle spinning solid state NMR

Symmetry based pulse sequences in magic angle spinning solid state NMR

strated a noticeable narrowing effect on the NMR spectra of abundant spins in solids when the sample was rotated at several kHz around an axis tilted by the angle arctan √ 2 = 54.74 ◦ with respect to the main magnetic field (see Magic Angle Spinning, Volume 5). However, the magic-angle spinning (MAS) method was not employed much at first because it was thought to be ineffective unless the spinning frequency greatly exceeded the size of the anisotropic nuclear spin interactions – a condition difficult to satisfy except for a limited number of samples. The situation changed at the end of the 1970s, when it was found that magic-angle spinning dramatically narrowed the proton- decoupled NMR peaks of isolated 13 C spins in organic solids. 3
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Effect of Texturing on the Wettability Characteristic of Carbide and 
              Steel Material by Grinding Process

Effect of Texturing on the Wettability Characteristic of Carbide and Steel Material by Grinding Process

Steel and carbide work piece of 18 mmx18mm x5 mm dimension are used as specimen. Electroplated textured wheel of 14mm width and 250 mm diameter is used for the grinding operation. For changing the grinding direction, different angle bars were used. During grinding, 5% by volume of NC 21A lubricant mixed with water at a flow rate of 177cm3/s is supplied via single nozzle (diameter 3 mm) at 20°C. Grinding wheel was balanced using Sigma Electronic SB-7002 balancing machine. The wheel is considered balanced when the recorded imbalance is less than 0.2μm. Wheel is also cleaned via jet of coolant after every experiment. Fig:1 gives the image of experimental set up.
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The imaging properties and sensitivity of the facial pits of pitvipers as determined by optical and heat transfer analysis

The imaging properties and sensitivity of the facial pits of pitvipers as determined by optical and heat transfer analysis

Limited understanding of the relevant optical and thermal physics of the facial pits is a common deficiency of existing studies. For example, a theoretical analysis of pit sensitivity (Jones et al., 2001) severely overestimated absorption of thermal radiation by the atmosphere and concluded that absorption limited the pit organ to a range of a few cm (Bakken, 2007). A number of researchers have presented pitvipers with thermal stimuli having surface temperatures equal to or exceeding body core temperature of typical prey items (e.g. Bullock and Barrett, 1968; Goris et al., 2000; Goris and Nomoto, 1967; Hartline et al., 1978; Pappas et al., 2004). However, the furred and feathered surfaces covering most of the body are actually closer to air temperature (e.g. Hill et al., 1980; Hill and Veghte, 1976; Kardong, 1986; Veghte and Herreid, 1965). Behavioral experiments have typically used a single target against a uniform thermal background. This may overestimate performance in natural habitats, because the angular resolution of the pit organ is likely poor (Otto, 1972; Stanford and Hartline, 1984). As a result, the radiation from small, warm objects is spread over a large area of the pit membrane and blended with non-uniform natural thermal backgrounds. The only experimental study known to have examined background effects (Theodoratus et al., 1997) placed test targets behind aquarium glass, which is completely opaque to thermal radiation (Hsieh and Su, 1979). Consequently, the reported responses are experimental artifacts. The foregoing review shows that there is a need for a comprehensive study that will define the input to the sensory system of a pitviper under relevant natural situations. Such a study requires detailed knowledge of the physical optics of the facial pit and its heat transfer properties. Prior studies (de Cock Buning, 1984; Otto, 1972) examined the distribution of radiation from a point source over the pit membrane using simplified geometric models, but lacked the modern computational tools needed to translate this information into a representation of the temperature contrast image on the pit membrane. Further, these studies omitted potentially important heat transfer processes such as convection and conduction from the pit membrane.
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Gravitational Lensing with a Large Deflection Angle as a Probe of General Relativity and the Galactic Center

Gravitational Lensing with a Large Deflection Angle as a Probe of General Relativity and the Galactic Center

There is a large observed stellar population in the galactic center. Of partic- ular interest are the dozens of discovered massive OB and Wolf-Rayet stars that orbit very near Sgr A*, some within the central arc second around Sgr A*. These particular stars are bright in the near-infrared (NIR) band, which, unlike light in the visible spectrum, can penetrate the dust in the galactic center to reach Earth. These stars are very young compared to the galaxy, and are in a region with high tidal forces inhospitable to star formation. This is known as the “paradox of youth” [107]. Two separate research groups have been monitoring the orbits of these close stars, known as S stars, in order to determine the mass of the central object at Sgr A* [108, 109, 110]. Both groups, one led by Andrea Ghez at UCLA and the other by Reinhard Genzel at the Max Planck Institute, set the mass of the dark object at Sgr A* to be around 4 million solar mass (M ). Observations of the star
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Aspect angle dependence of the E region irregularity velocity at large flow angles

Aspect angle dependence of the E region irregularity velocity at large flow angles

ed that equation (1) implies that the ions stream against the observed wave. Our analysis showed that for the phase velocity to be described well by equation (1) at large a the sign of the ion drift component should be reversed. One should note that all velocity polarities were consistent with those expected for this time of the day; the electron (ion) drifts were westward (poleward) and consistent with the westward plasma flow (poleward electric field) in the afternoon sector. The STARE Norway irregularity l-o-s velocity was positive (toward the radar), which is consistent with the electron drift component sign and numerous previous studies [e.g., Kohl et al., 1992; Koustov et al., 2002; Uspensky et al., 2004]. Both Kohl et al. [1992] and Koustov et al. [2002] have also noted that their results might have been affected by the finite neutral winds at altitudes of 100 – 110 km. However, the neutral wind magnitudes in the altitude range of interest are not expected to be considerably larger than 100 m/s [e.g., Nozawa and Brekke, 1995], whereas the ion drift components in our observations were 100 – 400 m/s and consistently close to the VHF velocity, Figure 7d. Clearly, this is an unexpected result, and the one that eludes explanation given our present understanding of the theory of electrojet irregularities.
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Particle size effect on caking in sucrose : a thesis presented in partial fulfilment of the requirements for the degree of Masters in Chemical Technology at Massey University

Particle size effect on caking in sucrose : a thesis presented in partial fulfilment of the requirements for the degree of Masters in Chemical Technology at Massey University

A-2 Figure A9 Angle required to break solid bridges in samples containing different proportions of 150-212 µm crystals, mixed with 600-850 µm crystals ... A-3 Figure AlO Angle required t[r]

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Illumination optics design for DMD Pico-projectors based on generalized functional method and microlens array

Illumination optics design for DMD Pico-projectors based on generalized functional method and microlens array

It is worth mentioning that the early microlens arrays are two discrete components in cascade. The physical properties of the two components were identical. How- ever, when assembling, the front and back sides of the microlens arrays should be kept strictly symmetrical, which requires a high assembling accuracy [6]. Due to the misalignment introduced in the assembly process, the fine beams segmented from the first row of micro- lenses cannot be fully imaged on the corresponding second row of microlenses, which will cause the eccen- tricity of the illumination system. As a result, the seg- mented beam cannot be concentrically superimposed on the target DMD panel, so that the illumination effi- ciency and uniformity will be dramatically decreased. The overflowing light will show bright lines on one side of the panel, which results in the flare when it is displayed on the projection screen. This phenomenon is similar to the large incident angle effect discussed in the following section. To avoid this phenomenon, two separated microlens array are combined into one inte- grated component, which is shown in Fig. 3. This structure increases the complexity of die processing and injection molding process, but greatly reduces the assembly error, and improves the illumination effi- ciency dramatically.
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Working Safely with Geotechnical Risk in Quarries

Working Safely with Geotechnical Risk in Quarries

Embankment stability is most important in tailings or settling ponds where any breach of the walls could cause inundation downstream or the engulfment of persons working below. Walls should be compacted and either vegetated (not trees or large shrubs) to stop erosion (including from animals) or rock armoured. This prevents inadvertent breaches from occurring but should include controls for overtopping to channel and divert overflow without eroding the pond wall.

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CRITICAL REVIEW ON FABRICATING AN EXPERIMENTAL SET-UP TO INVESTIGATED THE DEVELOPMENT AND DIAGNOSTIC STUDIES ON JET TESTER SOURCES AND GENERATION

CRITICAL REVIEW ON FABRICATING AN EXPERIMENTAL SET-UP TO INVESTIGATED THE DEVELOPMENT AND DIAGNOSTIC STUDIES ON JET TESTER SOURCES AND GENERATION

the new type solid impact test to know the properties of wear. The properties of wear are single layered and multi layered coatings. In PVD coatings, the 1.2 micrometer alumina parts are impacted at high velocity at different angles, different speed and different substrate temperature. And the result shows the coated materials has good wear properties than substrate materials.

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