Journal articles: 'Quarts rotatifs'

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Grundy, Anne, Michelle Cotterchio, Victoria A. Kirsh, Victoria Nadalin, Nancy Lightfoot, and Nancy Kreiger. "Association entre le travail par quarts et l’obésité chez les hommes dans le nord-est de l’Ontario." Promotion de la santé et prévention des maladies chroniques au Canada 37, no. 8 (August 2017): 261–71. http://dx.doi.org/10.24095/hpcdp.37.8.02f.

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Introduction Même si certaines études suggèrent une association entre le travail par quarts et l’obésité, peu sont fondées sur la population ou tiennent compte de divers horaires de travail par quarts. L’obésité étant associée à plusieurs problèmes de santé chroniques, il est important de comprendre quelles formes de travail par quarts ont une incidence sur elle et d’effectuer des travaux permettant d’évaluer de façon plus détaillée l’exposition au travail par quarts. Méthodologie Au moyen d’une régression logistique polytomique multivariée, nous avons étudié l’association entre le travail par quarts (de soir ou nuit, par quarts ou autre type de rotation) et le surpoids et l’obésité, en fonction d’une mesure transversale de l’indice de masse corporelle chez 1 561 hommes. Ces hommes avaient déjà servi de témoins dans une étude cas-témoins sur le cancer de la prostate menée dans le nord-est de l’Ontario de 1995 à 1999. Nous avons obtenu l’information sur leurs antécédents de travail (notamment sur le travail par quarts), leur taille et leur poids à partir de données autodéclarées recueillies par questionnaire. Résultats Nous avons observé une association entre le fait d’avoir déjà travaillé par quarts (par opposition au fait de n’avoir jamais travaillé par quarts) et le surpoids (RC [rapport de cotes] = 1,34; IC [intervalle de confiance] à 95 % : 1,05 à 1,73) ainsi que l’obésité (RC = 1,57; IC à 95 % : 1,12 à 2,21). Nous avons également observé des associations statistiquement non significatives avec le fait d’avoir déjà travaillé (par opposition au fait de n’avoir jamais travaillé) de façon permanente selon un quart de soir ou de nuit. Nous avons par ailleurs observé une tendance à la hausse statistiquement significative en ce qui concerne le risque de surpoids et d’obésité en fonction de la durée du travail par quarts. Conclusion Tant l’association positive observée entre le travail par quarts et l’obésité que l’association positive suggérée dans notre étude en ce qui concerne le travail permanent selon un quart de soir ou nuit concordent avec ce qui a été observé antérieurement. D’autres études en population tenant compte de nos résultats seront à mener pour examiner d’autres caractéristiques du travail par quarts, afin de mieux déterminer si certains types de travail par quarts ont une plus grande incidence sur l’obésité que d’autres.

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Wells, Stephen, Martin Dove, and Matthew Tucker. "Reverse Monte Carlo with geometric analysis – RMC+GA." Journal of Applied Crystallography 37, no. 4 (July 17, 2004): 536–44. http://dx.doi.org/10.1107/s0021889804008957.

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An analysis of simulated framework structures based on the rigid-unit model quantifies the distortion of polyhedra from their ideal geometric forms and decomposes the motions of the structure into components of rigid-unit displacement, rigid-unit rotation and distortion. Case studies analysing the behaviour of quartz and of other silicates demonstrate that the method provides a novel way of extracting information from reverse Monte Carlo simulations. A program calledGASPhas been developed to perform this analysis and is freely available to researchers. Rotations are handled using the rotor method of geometric algebra.

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BORDES, JOSÉ, HONG-MO CHAN, and SHEUNG TSUN TSOU. "A SOLUTION TO THE STRONG CP PROBLEM TRANSFORMING THE THETA ANGLE TO THE KM CP-VIOLATING PHASE." International Journal of Modern Physics A 25, no. 32 (December 30, 2010): 5897–911. http://dx.doi.org/10.1142/s0217751x10051165.

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It is shown that in the scheme with a rotating fermion mass matrix (i.e. one with a scale-dependent orientation in generation space) suggested earlier for explaining fermion mixing and mass hierarchy, the theta angle term in the QCD action of topological origin can be eliminated by chiral transformations, while giving still nonzero masses to all quarks. Instead, the effects of such transformations get transmitted by the rotation to the CKM matrix as the KM phase giving, for θ of order unity, a Jarlskog invariant typically of order 10-5, as experimentally observed. Strong and weak CP violations appear then as just two facets of the same phenomenon.

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Wheeler, John, Zhenting Jiang, David J. Prior, and Jan Tullis. "Dynamic Recrystallisation of Quartz." Materials Science Forum 467-470 (October 2004): 1243–50. http://dx.doi.org/10.4028/www.scientific.net/msf.467-470.1243.

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It is generally agreed that the driving force (plastic strain energy) is much too small to allow "classical" nucleation during static and dynamic recrystallisation, and that rotation/growth of subgrains is an alternative. The latter explanation predicts that new grains should begin at low angles to old grains. We have used electron backscatter diffraction on an experimentally deformed quartz polycrystal that has deformed by dislocation creep and partially recrystallised. In a region shortened by about 30% new grains are at high angles (much greater than 15º) to adjacent parent grains. A histogram of misorientation versus number of boundaries shows a gap at 15-20º. In its simple form we expect the subgrain rotation model to predict a spectrum of misorientations but with most of them being low angle. Instead, the histogram suggests that new boundaries began life as high-angle structures, so current models for deformation-induced nucleation require refinement.

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Kong, Yong, Yuming Wang, Liping Zhang, and Yiyuan Fang. "Off-axis transmission spectrum of quartz rotation filter." Optik 124, no. 12 (June 2013): 1128–31. http://dx.doi.org/10.1016/j.ijleo.2012.03.020.

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ANTUNES, ANTONIO CARLOS BAPTISTA, and LEILA JORGE ANTUNES. "DIQUARK FORMATION IN ANGULAR-MOMENTUM-EXCITED BARYONS." International Journal of Modern Physics A 24, no. 10 (April 20, 2009): 1987–94. http://dx.doi.org/10.1142/s0217751x09043249.

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Diquarks, or metastable clusters of two quarks inside baryons, are shown to be produced by angular momentum excitation. In baryons with a light quark and two heavy quarks with large angular momentum (L>2), the centrifugal barrier that appears in the rotation frame of the two heavy quarks prevents the light quark from passing freely between the two heavy quarks. The light quark must tunnelize through this potential barrier, which gives rise to the clusters of a light and a heavy quark.

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Bychkov, Igor V., Dmitry A. Kuzmin, V. A. Tolkachev, Hyoung In Lee, and Vladimir G. Shavrov. "Magnetic Speckle-Pattern Rotation in Gyrotropic Low-Mode Optical Fiber Coated by Conductive Nanoshell." Materials Science Forum 845 (March 2016): 207–10. http://dx.doi.org/10.4028/www.scientific.net/msf.845.207.

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We have investigated theoretically the possibility of control of magnetic speckle-pattern rotation in gyrotropic optical fiber coated by conductive nanoshell. Investigation has been carried out for graphene and silver coated fibers. In graphene-coated fiber speckle-pattern rotation may be tuned by both magnetic field and chemical potential of graphene. It is shown that fiber coating by conductive nanoshell may leads to suppression of magnetic speckle-pattern rotation even for low-gyrotropic quartz fiber.

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Shirtcliffe, N. "Deposition of clays onto a rotating, electrochemical, quartz crystal microbalance." Colloids and Surfaces A: Physicochemical and Engineering Aspects 155, no. 2-3 (September 1999): 277–85. http://dx.doi.org/10.1016/s0927-7757(98)00915-7.

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Fueten, F., and J. S. Goodchild. "Quartz c-axes orientation determination using the rotating polarizer microscope." Journal of Structural Geology 23, no. 6-7 (June 2001): 895–902. http://dx.doi.org/10.1016/s0191-8141(00)00161-9.

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Vearncombe, J. R. "Structure of veins in a gold–pyrite deposit in banded iron formation, Amalia greenstone belt, South Africa." Geological Magazine 123, no. 6 (November 1986): 601–9. http://dx.doi.org/10.1017/s0016756800024110.

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AbstractFibrous quartz veins in deformed banded iron formation of the Amalia greenstone belt, southwestern Transvaal, are spatially related to gold–pyrite mineralization in both wallrock and vein inclusions. Poles to quartz vein orientations show a general parallelism with mineral elongation and fold plunges of the principal deformation in the wallrock. Quartz vein fibres show a consistent anticlockwise rotation, late components being subparallel to the elongation lineation, suggesting veining was probably synchronous with the principal deformation. Antitaxial fibrous veins, which dominate the mineralized banded iron formation, formed by the process of crack–seal which channelled mineralizing fluids along the vein walls, increasing the potential for fluid–wallrock interaction. Gold mineralization in quartz veins occurs in wall-parallel slivers of banded iron formation which have been plucked off the vein wall during antitaxial fibre growth. Mineralization can be explained by a process of fluid–wallrock interaction with sulphidation and gold precipitation.

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KLYKOV, Yuri, Marina KHUDOYAN, and Georgy KIBIZOV. "DETERMINATION OF THE MECHANISM FOR OPENING QUARTZ PARTICLES WHEN GRINDING QUARTZ-CONTAINING PRODUCTS IN A CENTRIFUGAL MILL." Sustainable Development of Mountain Territories 12, no. 3 (September 30, 2020): 454–60. http://dx.doi.org/10.21177/1998-4502-2020-12-3-454-460.

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Introduction. Currently used grinding machines, among which drum mills are the most widely used, have a low efficiency, are bulky, are characterized by low specific productivity, significant consumption of steel for grinding bodies and lining, high noise level, and high energy consumption of the grinding process. The most promising devices of a new type that can effectively perform grinding operations at high technological rates are centrifugal mills. The centrifugal mill developed at SKGMI operates on the principle of self-grinding of pieces and particles of crushed mineral raw materials, when they collide and RUB in a mobile toroidal flow formed when the material moves between a rotating Cup-shaped rotor, a fixed body and the overlying layers of the crushed material. Grinding occurs due to the appearance of a gradient of particle velocities over the working body, due to their impact and, to a greater extent, abrasion. The tests of these mills for grinding various materials have shown high efficiency in operation, but until now, the issues of determining the physical and mechanical properties of the crushed material based on the establishment of the particle opening mechanism remain unresolved. The purpose of the tests. Determination of the physical and mechanical properties of the crushed material in a centrifugal mill based on the establishment of the particle opening mechanism. Test procedure. To solve this problem, a vertical centrifugal mill MC-600 with a rotor diameter of 600 mm was used. Tests of the centrifugal mill were carried out according to the following method. The speed of rotation of the rotor was 4.8 and 8.4 s-1, the height of the material column above the rotor was at the level of 250 and 350 mm; 6 radial ribs were installed in the rotor cavity of the mill. The time of each test was 4 hours. The tests were repeated 3–5 times for each mode of operation of the mill. Quartz was used as a reference material for determining the relative pulverizability coefficient. The research was carried out in the production conditions of the Izhevsk machinebuilding plant during the regeneration of spent molding quartz mixtures. Pieces of a liquid-glass mixture based on quartz sand with strength of 1.3 MPa and 4.25 MPa were used as the crushed material. The crushed material was dispersed according to the standard method for each hour of operation of the mill. Samples were taken in the size class -0.200 + 0.074 mm for their fractional analysis by size. Test result. 1. It was Found that the maximum productivity of a centrifugal mill when grinding pieces of material with a strength of 1.3 MPa was achieved with a loading weight of 90–100 kg, and with a strength of 4.25 MPa – 100–110 kg, which indicates the need to create an increased normal pressure of the layers of crushed material located above the mill rotor. It was found that the maximum productivity of a centrifugal mill when grinding pieces of material with a strength of 1.3 MPa and a rotor rotation frequency of 8.4 s-1 was 13.16 t/h, and when grinding pieces of material with a strength of 4.25 MPa – 10.0 t/h. 2. The Dependence of power consumption on the weight of the mill load and the rotor speed increases when the load weight is more than 100 kg. 3. The Highest fraction content of class -0.4 +0.16 mm is 72.14 %, and the content of class -0.074 mm is 3.9 %, i.e. there is no re-grinding of the source material. 4. The specific productivity of the centrifugal mill for the newly formed calculated size classes -0.074 mm and -0.200 mm was 1.28 t/h and 13.0 t/h, respectively. 5. Microscopic study of anshlifov showed that quartz grains in the crushed material mostly have a rounded shape, on average 90–95 % of the grains. In the initial material, about 90% of quartz joints with a binder, and in the crushed material, the number of joints does not exceed 3–5%. Thus, the degree of expansion of quartz reaches to 0.87. Conclusions. The paper presents the results of studies of a centrifugal mill in the conditions of the Izhevsk machinebuilding plant when grinding quartz-containing products. The physical and mechanical properties of the crushed material that significantly affect the efficiency of grinding are determined. The mechanism of the disclosure particles of quartz, which is primarily the mineral content of many ores and defined particle size obtained by grinding. At the same time, it was found that a large yield of thin classes significantly reduces the efficiency of further technology.

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Kern, P., and D. Landolt. "Design and Characterization of a Rotating Electrochemical Quartz-Crystal-Microbalance Electrode." Journal of The Electrochemical Society 147, no. 1 (2000): 318. http://dx.doi.org/10.1149/1.1393193.

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Keszthelyi, L. "Origin of the homochirality of biomolecules." Quarterly Reviews of Biophysics 28, no. 4 (November 1995): 473–507. http://dx.doi.org/10.1017/s0033583500003309.

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Molecules built up from a given set of atoms may differ in their three-dimensional structure. They may have one or more asymmetric centres that serve as reference points for the steric distribution of the atoms. Carbon atoms, common to all biomolecules, are often such centres. For example, the Cα atom between the carboxyl and amino groups in amino acids is an asymmetric centre: looking ON ward (i.e. from the carbOxyl to the amiNo group, with the Cα oriented so that it is above the carboxyl and amino groups) the radical characterizing the amino acid may be to the right (D-molecules) or to the left (L-molecules). Nineteen of the 20 amino acids occurring in proteins have such a structure (the exception is glycine, where the radical is a hydrogen atom). These pairs of molecules cannot be brought into coincidence with their own mirror image, as is the situation with our hands. The phenomenon has therefore been named handedness, or chirality, from the Greek word cheir, meaning hand. The two forms of the chiral molecules are called enantiomers or antipodes. They differ in rotating the plane of the polarized light either to the right or to the left. The sense of rotation depends on the wavelength of the measuring light, but at a given wavelength it is always opposite for a pair of enantiomers. Chirality may also occur when achiral molecules form chiral substances during crystallization (for example, quartz forms D-quartz or Lquartz). A detailed theoretical treatment of molecular chirality is given by Barron (1991).

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Damm, V., K. Feldmann, A. Frischbutter, W. Kleinsteuber, and K. Walther. "The Structural Evolution of an Orthogneiss-fold Within the Reitzenhainer Rotgneisstruktur (Erzgebirge Mts., GDR)." Textures and Microstructures 12, no. 1-3 (January 1, 1990): 15–35. http://dx.doi.org/10.1155/tsm.12.15.

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The crystallographic preferred orientations of quartz in gneiss taken from different spots of a recumbent fold structure in the Erzgebirge Mts. (southern GDR) are studied by means of neutron time-of-flight diffraction. A single component texture has been found for all specimens, with quartz c-axes parallel to the tectonic a-direction. The variations in texture sharpness are related to different deformation conditions of the samples. A fabric rotation of 30° has been found from the limb to the crest of the fold on the basis of (101¯0) and (112¯0) pole figures. The basal pole figures of quartz derived from an ODF analysis compared well with optical U-stage measurements. The determined fabrics are discussed taking into account model calculations of experimentally deformed quartzites and geological informations.

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Roark, J., X. Du, C. Constantinou, V. Dexheimer, A. W. Steiner, and J. R. Stone. "Hyperons and quarks in proto-neutron stars." Monthly Notices of the Royal Astronomical Society 486, no. 4 (May 4, 2019): 5441–47. http://dx.doi.org/10.1093/mnras/stz1240.

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ABSTRACT In this work, we study matter in the cores of proto-neutron stars, focusing on the impact of their composition on the stellar structure. We begin by examining the effects of finite temperature (through a fixed entropy per baryon) and lepton fraction on purely nucleonic matter by making use of the DSH (Du, Steiner & Holt) model. We then turn our attention to a relativistic mean-field model containing exotic degrees of freedom, the Chiral Mean Field (CMF) model, again, under the conditions of finite temperature and trapped neutrinos. In the latter, since both hyperons and quarks are found in the cores of large-mass stars, their interplay and the possibility of mixtures of phases is taken into account and analysed. Finally, we discuss how stellar rotation can affect our results.

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Ore, Erenn, and Gehan Amaratunga. "Cylindrical Ultra-Thin a-Si:H Photovoltaic Cell With No Doped Layers." MRS Advances 2, no. 15 (2017): 825–33. http://dx.doi.org/10.1557/adv.2017.224.

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ABSTRACTIn order to collect the hot electrons, light trapping using cylindrical quartz substrates for ultra-thin a-Si:H photovoltaic cells with no doped layers is introduced. The photovoltaic cell has the structure of 2nmMoOx(hole collection layer) – 10nmintrinsic a-Si:H (photoactive layer) – 1.5nmLiF / 300nmAl (electron collection layer and back electrode), all deposited in that order onto a cylindrical quartz substrate covered with a 100nmITO layer, which is acting as the transparent front electrode for the cell. By rotating the cell with respect to the incoming light, the angle of incidence of the incoming light for which the cell efficiency is at its highest value, is determined.

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Abdukadyrova, I. Kh. "Influence of neutrons on the rotation of the polarization plane of quartz." Soviet Atomic Energy 59, no. 5 (November 1985): 950–51. http://dx.doi.org/10.1007/bf01133099.

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Chiang, Kwan C. "Anatomy of spacetime and possible origins of internal symmetry and all particle quantum numbers." Physics Essays 33, no. 3 (September 28, 2020): 342–47. http://dx.doi.org/10.4006/0836-1398-33.3.342.

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Not driven by observations, this paper digs into the “internal workings” of spacetime. Through logical deductions, micro dimensions appear to be uncovered, with possible SU(4) or SU(5): 1. It is thought that special relativity merely initiated the definition of spacetime, but more scales are yet to be defined. 2. In the definition of spacetime, EM (electromagnetism) played another critical role, i.e., the six circular magnetic and electric field lines (running on the six planes) cross and “define equivalencies” between the four linear scales. Without this definition, light would not be measured at the same speed in different directions. Being a gauge theory, EM defines two things: Linear scales and “equivalencies” between linear scales. 3. For any scale (and their equivalencies), there could be no or many arbitrarily assumed definitions, or a concrete definition based on relevant physics. Nature would conform with but the one based on relevant physics, because Nature itself is consisted of that relevant physics. Thus, the principle: No scale and their equivalencies are meaningful unless defined by relevant physics. 4. Then, what are those fields running (and defining equivalencies between the six “angle scales”) on the six planes of the 4D spacetime? It is believed to be the “classical” weak fields which run in solid angles (or “3D angles”) between the six planes. (The only suspicion is that this rotation does not preserve vector length, which is not a problem ultimately.) 5. If the six angle scales are drawn as six axes of a 6D superspace, then the “3D angle” rotations look like “plane angle” rotations and cause SO(6)∼SU(4) [or SO(10)∼SU(5) for 5D spacetime], which appears to match baryon spectrum without quarks. 6. Since this rotation is between “planes” of the “external” spacetime, no linear dimension is visible, yet causing P-violations. 7. Similarly, fields running in 4D and 5D angle rotations (between 3D and 4D surfaces) must also exist, which may be responsible for CP-violation and strong interactions. 8. The 5D angle rotations may be generating Baryon and Lepton numbers and hence explaining their conservation behaviors, e.g., no proton decay. 9. It can be inferred, if 3D, 4D (and 5D) angle rotation fields did not exist, the 4D (and 5D) spacetime would be warped and the four (or five) linear axes would not be perpendicular to each other. 10. EM was simplified and turned elegant “only” after redefinition of spacetime by special relativity. Likewise, weak, CP-violation and strong interactions are expected to simplify and turn as elegant as EM when 2D (plane), 3D, and 4D angle scales are defined by weak, CP-violation, and strong forces, respectively. 11. Verifications as accurate as EM are expected too. 12. Mathematically, higher angle rotations thought to be inexistent only because it does not conserve vector length. Actually, they did not vanish and their symmetries would surface in particle classifications when linear momentum is not concerned. Micro dimensions being invisible is because symmetries do not have to happen between linear axes, but can happen between 2-, 3- or 4-surfaces. These geometries together generate the complete particles spectrum.

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Minkowski, Peter. "Mass generation in QCD — Oscillating quarks and gluons." International Journal of Modern Physics A 29, no. 21 (August 20, 2014): 1444015. http://dx.doi.org/10.1142/s0217751x14440151.

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The present lecture is devoted to embedding the approximate genuine harmonic oscillator structure of valence [Formula: see text] mesons and in more detail the qqq configurations for u, d, s flavored baryons in QCD for three light flavors of quark. It includes notes, preparing the counting of "oscillatory modes of N fl = 3 light quarks, u, d, s in baryons," using the [Formula: see text] broken symmetry classification, extended to the harmonic oscillator symmetry of 3 paired oscillator modes. [Formula: see text] stands for the space rotation group generated by the sum of the 3 individual angular momenta of quarks in their c.m. system. The oscillator extension to valence gauge boson states is not yet developed to a comparable level.

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Ghoroku, Kazuo, and Kouki Kubo. "Accelerated quarks and energy loss in confinement theory." International Journal of Modern Physics A 31, no. 18 (June 29, 2016): 1650103. http://dx.doi.org/10.1142/s0217751x16501037.

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We study the energy loss rate (ELR) of the accelerated quark in terms of the holographic models for the two different motions, linear acceleration and uniform rotation. They are examined by two different nonconformal models with confinement. We found in both models that the value of ELR is bounded from below by the string tension of the linear confinement potential between quark and antiquark. The lower bounds of ELR are independent of the types of the motion of the quark. They are determined by the string tension at the worldsheet horizon of the model. These results are obtained when the model has the diagonal background metric. Then we find the common perspective for the lower bounds of ELRs of the two different motions.

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Renault, Jacques, Chris McKee, and James Barker. "Calibrating for X-Ray Diffraction Analysis of Trace Quartz." Advances in X-ray Analysis 35, A (1991): 363–73. http://dx.doi.org/10.1154/s0376030800009034.

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AbstractTrace analysis of quartz at the <0.1 wt% level can be routinely accomplished by x-ray diffraction using rotating pressed-powder briquettes and a peak deconvolution strategy due to Wiedemann, et al. (1937a, b) which permits reproducible determination of background and enhances peak resolution without changing the integrated intensity.Four calibration methods were tested: (1) calibration with perlites microscopically analyzed by Hamilton and Peletls (1988), (2) with artificial mixtures of quartz and glass, (3) with chemical analysis and massbalance calculation of quartz in glass mixtures, and (4) with a new method of additions for XRD.Methods (2) and (4) gave the best results. Method (2) has a precision of 16.9 pet at the 0.1 wt% level and a LLD of 0.05 wt% at 3σ. Method (4) is particularly attractive because large spikes can be used which minimize homogenization errors and permit preparation of standards which have properties very similar to run-of-the-mill samples; the problem of non-zero intercepts is avoided.

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Kabana, Sonia, and Peter Minkowski. "Counting of oscillatory modes of valence quarks forming qqq baryons for three quark flavors u, d, s." International Journal of Modern Physics A 32, no. 04 (February 9, 2017): 1750004. http://dx.doi.org/10.1142/s0217751x1750004x.

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We present the unique properties of oscillatory modes of [Formula: see text] light quarks — [Formula: see text], [Formula: see text], [Formula: see text] — using the [Formula: see text] broken symmetry classification. [Formula: see text] stands for the space rotation group generated by the sum of the three individual angular momenta of quarks in their c.m. system. The baryonic multiplets are shown to emerge from the picture of oscillating quarks in three space dimensions in the center-of-mass system of the baryons. All oscillatory modes are fully relativistic with a finite number of oscillators and this is forming the unique harmonic oscillator with these properties. The density of states as a function of mass-square is calculated. This estimate is of relevance for the accounting of the missing states of unobserved hadrons, as the here estimated baryonic multiplets include both the observed and the unobserved (or “missing”) hadrons. The estimate is conceptually different from Hagedorn’s model and is based on field theory of QCD.

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HOVDEBO, JORDAN L., MARTÍN KRUCZENSKI, DAVID MATEOS, ROBERT C. MYERS, and DAVID J. WINTERS. "HOLOGRAPHIC MESONS: ADDING FLAVOR TO THE ADS/CFT DUALITY." International Journal of Modern Physics A 20, no. 15 (June 20, 2005): 3428–33. http://dx.doi.org/10.1142/s0217751x05026728.

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We study mesons in an [Formula: see text] super Yang-Mills theory with fundamental matter from its dual string theory on AdS5 × S5 with a D7-brane probe. For quarks with a finite mass mq, the meson spectrum is discrete and exhibits a mass gap of order [Formula: see text]. The spectrum of mesons with large spin J is obtained from semiclassical rotating open strings attached to the D7-brane. It displays Regge behaviour for [Formula: see text] whereas for [Formula: see text] it corresponds to that of two non-relativistic quarks bound by a Coulomb potential. We calculate 〈 Tr F2〉 around an isolated quark, to gain insight into the Regge behaviour of the spinning mesons.

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Capitani, Giancarlo. "Synchysite-(Ce) from Cinquevalli (Trento, Italy): Stacking Disorder and the Polytypism of (Ca,REE)-Fluorcarbonates." Minerals 10, no. 1 (January 18, 2020): 77. http://dx.doi.org/10.3390/min10010077.

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Synchysite-(Ce) at Cinquevalli occurs as fine needles intergrown with quartz in quartz-dikes and in association with altered K-feldspar and oxidized chalcopyrite as major constituents. Synchysite-(Ce) [Ca1.00(Ce0.43La0.26Nd0.17Y0.07Pr0.04Sm0.02Gd0.01)Σ=1.00(CO3)2(F0.58(OH)0.42)], shows an overgrowth rim of bastnäsite-(Ce) [(Ce0.34La0.25Nd0.17Pb0.07C a0.06Y0.06Pr0.04S m0.02Gd0.01)Σ=1.00C O3(F0.75(OH)0.25)]. Unit cell refinement of synchysite (C2/c) and bastnäsite (P62c) led to a = 12.272(4), b = 7.100(2), c = 18.640(5) Å, β = 102.71(5)°, and a = 7.085(1), c = 9.746(2) Å, respectively. Polysomatic faults are sporadic, but polytypic disorder is widespread. High resolution transmission electron microscopy images taken along [100] or ⟨130⟩ show an apparent order and the related diffraction patterns are streak-free. Conversely, along [010] or ⟨110⟩, a high density of stacking faults is observed and the related diffraction patterns show hhl rows with h ≠ 3n affected by streaks. No ordered domain larger than a few unit cells was detected. The stacking sequence of (Ca,REE)-fluorcarbonates can be compared with subfamily-B mica polytypes (2M2, 2O and 6H), which are characterized by n·60° (n = odd) rotations. Subfamily-A polytypes (1M, 2M1 and 3T), characterized by n·60° (n = even) rotations, should not be possible. Synchysite, characterized by ±60° rotations, can be likened to the 2M2 polytype.

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Finkelstein, Robert J. "On the SLq(2) extension of the standard model and the concept of charge." International Journal of Modern Physics A 32, no. 02n03 (January 25, 2017): 1730001. http://dx.doi.org/10.1142/s0217751x17300010.

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Our SLq(2) extension of the standard model is constructed by replacing the elementary field operators, [Formula: see text], of the standard model by [Formula: see text] where [Formula: see text] is an element of the [Formula: see text]-dimensional representation of the SLq(2) algebra, which is also the knot algebra. The allowed quantum states [Formula: see text] are restricted by the topological conditions [Formula: see text] postulated between the states of the quantum knot [Formula: see text] and the corresponding classical knot [Formula: see text] where the [Formula: see text] are (the number of crossings, the writhe, the rotation) of the 2d projection of the corresponding oriented classical knot. Here, [Formula: see text] is an odd number that is required by the difference in parity between [Formula: see text] and [Formula: see text]. There is also the empirical restriction on the allowed states [Formula: see text] that holds at the [Formula: see text] level, connecting quantum trefoils [Formula: see text] with leptons and quarks [Formula: see text]. The so-constructed knotted leptons and quarks turn out to be composed of three [Formula: see text] particles which unexpectedly agree with the preon models of Harrari and Shupe. The [Formula: see text] particles, being electroweak neutral, are dark and plausibly greatly outnumber the quarks and leptons. The SLq(2) or [Formula: see text] measure of charge has a direct physical interpretation since [Formula: see text] is the total number of preonic charges while [Formula: see text] and [Formula: see text] are the numbers of writhe and rotation sources of preonic charge. The total SLq(2) charge of a particle, measured by writhe and rotation and composed of preons, sums the signs of the counterclockwise turns [Formula: see text] and clockwise turns [Formula: see text] that any energy–momentum current makes in going once around the knot. In this way, the handedness of the knot reduces charge to a geometric concept similar to the way that curvature of space–time encodes mass and energy. According to this model, the leptons and quarks are [Formula: see text] particles, the preons are [Formula: see text] particles, and the [Formula: see text] particles are candidates for dark matter. It is possible to understand [Formula: see text] as a simple deformation parameter or as the ratio [Formula: see text] of the electroweak to the gluon coupling constants.

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Zhang, Chaozhu, Jinan Han, and Ke Li. "Design and Implementation of Hybrid CORDIC Algorithm Based on Phase Rotation Estimation for NCO." Scientific World Journal 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/897381.

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The numerical controlled oscillator has wide application in radar, digital receiver, and software radio system. Firstly, this paper introduces the traditional CORDIC algorithm. Then in order to improve computing speed and save resources, this paper proposes a kind of hybrid CORDIC algorithm based on phase rotation estimation applied in numerical controlled oscillator (NCO). Through estimating the direction of part phase rotation, the algorithm reduces part phase rotation and add-subtract unit, so that it decreases delay. Furthermore, the paper simulates and implements the numerical controlled oscillator by Quartus II software and Modelsim software. Finally, simulation results indicate that the improvement over traditional CORDIC algorithm is achieved in terms of ease of computation, resource utilization, and computing speed/delay while maintaining the precision. It is suitable for high speed and precision digital modulation and demodulation.

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Sustavov, O. A. "Dynamic recrystallization of quartz in veins in sandstones of metagenesis zone (Kular district, Yakutia)." Proceedings of higher educational establishments. Geology and Exploration, no. 6 (January 3, 2019): 33–40. http://dx.doi.org/10.32454/0016-7762-2018-6-33-40.

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Bulging recrystallization (BR) has been considered in the deformed quartz veins in the lower Triassic sandstones of the metagenesis zone in the North-Western part of the Kular district, Yakutia. BR is characterized by the formation of sutured boundaries of individuals during the crystalloplastic deformation of quarz. To these boundaries, the recrystallization grains are confined, the size of which (in this case, 0,01—0,02 mm) corresponds to the size of the teeth at the boundaries of individuals. Such fine recrystallization grains can fix with their formation the peak crustal stresses arising up during deformation of the continental crust near the brittle-plastic transition. Inside the individuals, BR is accompanied by recrystallization along the microshears and deformation bands with the leading role of progressive rotation of subgrains. BR in vein quartz occurs during the formation of the pressure solution cleavage in the host sandstones, and therefore the combination of the pressure solution cleavage in the sandstones of the metagenesis zone and BR in vein quartz can be considered as structural paragenesis.

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Gao, Fei, Yong Kong, XiaoLi Zhao, Keke Song, Xiangkai Zhao, and Mingming Shen. "The Temperature Effect on the Transmission Spectrum of the Quartz Optical Rotation Filter." Оптика и спектроскопия 116, no. 2 (2014): 336–39. http://dx.doi.org/10.7868/s0030403414020068.

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Gao, Fei, Yong Kong, XiaoLi Zhao, Keke Song, Xiangkai Zhao, and Mingming Shen. "The temperature effect on the transmission spectrum of the quartz optical rotation filter." Optics and Spectroscopy 116, no. 2 (February 2014): 311–14. http://dx.doi.org/10.1134/s0030400x14020064.

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Vorob’ev, S. I., A. L. Getalov, E. N. Komarov, S. A. Kotov, I. I. Pavlova, A. E. Moroslip, and G. V. Shcherbakov. "Muon-spin-rotation study of muon polarization losses in plastic scintillators and quartz." JETP Letters 97, no. 12 (August 2013): 661–63. http://dx.doi.org/10.1134/s0021364013120138.

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Okada, A., Jin-Yong Ahn, S. Inoue, T. Yamaguchi, and M. Imamura. "Faraday rotation in quaternary CdMnCoTe thick films deposited on transparent quartz glass substrates." IEEE Transactions on Magnetics 39, no. 5 (September 2003): 3175–77. http://dx.doi.org/10.1109/tmag.2003.816048.

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Bordes, José, Hong-Mo Chan, and Sheung Tsun Tsou. "A first test of the framed standard model against experiment." International Journal of Modern Physics A 30, no. 11 (April 16, 2015): 1550051. http://dx.doi.org/10.1142/s0217751x15500517.

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The framed standard model (FSM) is obtained from the standard model by incorporating, as field variables, the frame vectors (vielbeins) in internal symmetry space. It gives the standard Higgs boson and 3 generations of quarks and leptons as immediate consequences. It gives moreover a fermion mass matrix of the form: m = mTαα†, where α is a vector in generation space independent of the fermion species and rotating with changing scale, which has already been shown to lead, generically, to up–down mixing, neutrino oscillations and mass hierarchy. In this paper, pushing the FSM further, one first derives to 1-loop order the RGE for the rotation of α, and then applies it to fit mass and mixing data as a first test of the model. With 7 real adjustable parameters, 18 measured quantities are fitted, most (12) to within experimental error or to better than 0.5 percent, and the rest (6) not far off. (A summary of this fit can be found in Table 2 of this paper.) Two notable features, both generic to FSM, not just specific to the fit, are: (i) that a theta-angle of order unity in the instanton term in QCD would translate via rotation into a Kobayashi–Maskawa phase in the CKM matrix of about the observed magnitude (J ~ 10-5), (ii) that it would come out correctly that mu < md, despite the fact that mt ≫ mb, mc ≫ ms. Of the 18 quantities fitted, 12 are deemed independent in the usual formulation of the standard model. In fact, the fit gives a total of 17 independent parameters of the standard model, but 5 of these have not been measured by experiment.

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KOVNER, A., and B. ROSENSTEIN. "QUARKS AS TOPOLOGICAL DEFECTS — OR, WHAT IS CONFINED INSIDE A HADRON?" International Journal of Modern Physics A 08, no. 31 (December 20, 1993): 5575–604. http://dx.doi.org/10.1142/s0217751x93002204.

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We present a picture of confinement based on representation of constituent quarks as pointlike topological defects. The topological charge carried by quarks and confined in hadrons is explicitly constructed in terms of Yang-Mills variables. In 2+1 dimensions we are able to construct a local complex scalar field V(x), in terms of which the topological charge is [Formula: see text]. The VEV of the field V in the confining phase is nonzero and the charge is the winding number corresponding to homotopy group π1(S1). Quarks carry the charge Q and therefore are topological solitons. The phase rotation of V is generated by the operator of magnetic flux. Unlike in QED, the U(1) magnetic flux is explicitly broken by the monopoles. This results in formation of a string between a quark and an antiquark. The effective Lagrangian for V is derived in models with adjoint and fundamental quarks. This topological mechanism of confinement is basically different from the one proposed by ’t Hooft in which the elementary objects are linelike domain walls. A baryon is described as a Y-shaped configuration of strings. In 3+1 dimensions the explicit expression for V, and therefore a detailed picture, is not available. However, assuming the validity of the same mechanism we point out several interesting qualitative consequences.

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Ajithkumar, K. C., and K. Pramod. "DEVELOPMENT AND VALIDATION OF A MODIFIED POLARIMETRIC ASSAY METHOD FOR SMALL VOLUME SAMPLES." International Journal of Applied Pharmaceutics 9, no. 6 (November 8, 2017): 91. http://dx.doi.org/10.22159/ijap.2017v9i6.22459.

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Objective: The objective of the present work was to develop a method to be useful for analyzing small volume samples of an optically active compound.Methods: The method employed quartz cuvette instead of a polarimeter tube. Quantification of optically active compound was successfully validated in terms of linearity and range, precision and robustness. The detection limit (DL) and quantitation limit (QL) were determined as per the ICH guidelines.Results: Polarimetry generally involves the quantification of optically active compounds by measuring its ability to rotate (in terms of angle of rotation) polarized light passed through it. The plot of angle of rotation versus concentration was linear in wide range of concentration with excellent coefficient of determination of 0.9989±0.0008. The low values of % relative standard deviation (RSD) for repeatability and intermediate precision suggested an excellent precision of the developed polarimetric method. The detection limit (DL) and quantitation limit (QL) were determined were found to be 0.5025 and 1.5225 %w/v respectively.Conclusion: A modified polarimetric method for the quantification of dextrose was successfully developed and validated. The method employed quartz cuvette instead of polarimeter tube. The method is expected to be useful in a variety of industries where dextrose finds its application. The method can also be extended to other optically active compounds.

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Cameron, R. P., U. Vogl, and N. Trautmann. "Interference-contrast optical activity: a new technique for probing the chirality of anisotropic samples and more." Royal Society Open Science 7, no. 5 (May 2020): 192201. http://dx.doi.org/10.1098/rsos.192201.

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We introduce interference-contrast optical activity (ICOA) as a new technique for probing the chirality of anisotropic samples and more. ICOA could underpin a new class of ‘chiral microscopes’, with potential applications spanning the range of chirality and beyond. Two possible versions of ICOA are described explicitly; one designed to probe the optical rotation of a transparent sample regardless of the sample’s linear birefringence (ICOA-OR) and another designed to probe gradients in the optical rotation of a transparent sample (ICOA-GOR). Simulated results for α -quartz lead us to suggest that ICOA-GOR might be applied to help monitor the growth of chiral crystals in the pharmaceutical industry. Possible directions for future research are highlighted.

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Islam, Md Mahfujul, and Fredric Datchi. "Polarized Raman Spectra of α Quartz." International Letters of Chemistry, Physics and Astronomy 56 (July 2015): 91–98. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.56.91.

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The purpose of this experiment was to observe the Raman shift to assign the symmetry character of the obtained vibrational modes of α-quartz (which has 9 atom per unit cell) using the selection rules for Raman Effect. We observed the Raman spectra varying the polarization of the incoming beam and the orientation of the crystal. And we used monochromatic radiation of argon laser of wavelength 540 nm for our Raman spectroscopy. We observed the intensity of light rotating the polarizer to vertical position from its horizontal position with respect to the plane of the optical table where the laser is placed and measured the Raman spectra over an energy from 50 to 1250 cm-1 using the laser power of 1W and an acquisition time of 10 sec. averaging over 2 acquisitions. From our experiment we can see that here is 4symmetry for A1 which is predicted on our vibrational modes. However for E symmetry mode we have observed 14 vibrational modes but as E is doubly degenerate there should be 16 vibrational modes on the Raman active modes in the α quartz, as we can see that there are two vibration missing ,it happens may be due to noise on the surroundings. We got different peaks due to the different intensities and the different orientation of the laser beam hitting the sample on different angle. The different intensities of the peaks for the different orientation might be due to the laser beam hitting the samples at different angles due to differences in the orientation of the surfaces. We also found that the biggest amount of the re-radiated light was vibrating horizontally, i.e. in the same direction as the laser beam hitting the sample.

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Fazio, Eugenio, Patrizia Fiannacca, Damiano Russo, and Rosolino Cirrincione. "Submagmatic to Solid-State Deformation Microstructures Recorded in Cooling Granitoids during Exhumation of Late-Variscan Crust in North-Eastern Sicily." Geosciences 10, no. 8 (August 13, 2020): 311. http://dx.doi.org/10.3390/geosciences10080311.

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Late-Variscan granitoid rocks of trondhjemitic and granitic composition, intruded in migmatitic paragneisses in the north-eastern Peloritani Mountains (southern Italy) at ~310 Ma and ~300 Ma, respectively, exhibit a range of deformation microstructures developed under a shear regime at decreasing temperatures. Non-coaxial deformation is documented by sigmoidal feldspar porphyroclasts, mica fish, and asymmetric boudins affecting tiny andalusite crystals. Late-Variscan shearing during granitoid cooling is constrained by largely represented chessboard patterns in quartz and, especially, submagmatic fractures in plagioclase, indicating deformation at high-temperature conditions (T > 650 °C), in the presence of melt. Submagmatic deformation was extensively superseded by deformation at lower temperatures. Examples of solid state-high temperature deformation-related microstructures (T > 450 °C) include feldspar bulging, quartz grain boundary migration, and subgrain rotation recrystallization. Finally, low temperature subsolidus microstructures (T < 450 °C) consist of quartz bulging, mica kinks, and feldspar twinning and bending. A complete sequence of deformation, operating from submagmatic to low-temperature subsolidus conditions is recorded in both the older and younger granitoids, suggesting a duration of ~20 Ma for shear zone activity during post-collisional exhumation of the Variscan middle crust in southernmost Italy.

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DE PAOLIS, F., G. INGROSSO, A. A. NUCITA, and ASGHAR QADIR. "CENTRIFUGAL FORCE INDUCED COLLAPSE OF STRANGE STARS INTO BLACK HOLES." International Journal of Modern Physics D 16, no. 05 (May 2007): 827–31. http://dx.doi.org/10.1142/s0218271807010420.

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It has been suggested that there could be objects even more compact than neutron stars, like the so-called strange stars, P-stars, and magnetars. Strange stars are collapsed stars consisting of u, d, and s quarks. P-stars are a new class of compact stars made of u and d quarks in β-equilibrium with electrons in an Abelian chromomagnetic condensate. It has also been shown that a particle in a circular orbit around a stationary black hole is subject to a centrifugal force that turns out to be directed inwards if the particle orbit radius is between the Schwarzschild radius rs and 3rs/2. Here it is proposed that rotation of a sufficiently compact collapsed object may lead to a centrifugal force induced collapse to a black hole that could emit short gamma-ray bursts.

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Menezes, Luís Fernando Glasenapp de, João Restle, Ivan Luiz Brondani, Dari Celestino Alves Filho, Leonir Luiz Pascoal, and José Henrique Souza da Silva. "Distribuição de gorduras internas e de descarte e componentes externos do corpo de novilhos de gerações avançadas do cruzamento rotativo entre as raças Charolês e Nelore." Revista Brasileira de Zootecnia 38, no. 2 (February 2009): 338–45. http://dx.doi.org/10.1590/s1516-35982009000200017.

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Foram avaliados os efeitos de heterose e grupo genético na distribuição das gorduras internas e de descarte e dos componentes externos do corpo de novilhos puros, Charolês (C) e Nelore (N), e mestiços de segunda (¾C × ¼N e ¾N × ¼C), terceira (5/8C × 3/8N e 5/8N × 3/8C) e quarta gerações (11/16C × 5/16N e 11/16N × 5/16C) de cruzamento terminados em confinamento. Em comparação à média dos puros, os novilhos de segunda geração apresentaram maior peso absoluto das gorduras renal, intestinal e total, resultando em heterose de 39,88; 43,96 e 31,80%, respectivamente. A gordura ruminal dos novilhos da quarta geração foi 41,48% maior que a média dos puros. Quando expressa em porcentagem do peso do corpo vazio (PCV), os animais da segunda geração foram superiores aos puros somente em relação à gordura intestinal, apresentando heterose de 28,06%. Os animais de quarta geração foram 21,67% inferiores aos puros quando a gordura de toalete foi expressa por 100 kg de PCV. Novilhos Charolês tiveram maior peso absoluto de gordura de descarte em relação aos novilhos Nelore (2,85 vs 1,30 kg). Nos novilhos ¾C × ¼N, a gordura intestinal foi maior que nos ¾N × ¼C, em pesos absoluto (10,15 vs 7,83 kg) e relativo (2,59 vs 2,02%). O peso de gordura ruminal nos animais 11/16N × 5/16C foi maior que nos 11/16C × 5/16N (6,93 vs 4,94 kg). A heterose para o peso relativo da cabeça foi significativa na terceira (-15,54%) e quarta (-13,12%) gerações de cruzamento, enquanto a heterose para o peso relativo das patas foi significativa apenas na terceira geração (-11,08%). O peso relativo das patas nos novilhos Charolês foi maior que nos Nelore (2,18 vs 1,88%). As gorduras não-integrantes da carcaça apresentam heterose significativa no cruzamento rotativo entre as raças Charolês e Nelore.

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Aoki, Takashi, and Yasuo Yoshida. "Dependence of Rotation Speeds of Ultrasonic Quartz Motor on Length in Z-Axis Direction." Japanese Journal of Applied Physics 35, Part 2, No. 6A (June 1, 1996): L713—L714. http://dx.doi.org/10.1143/jjap.35.l713.

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Aoki, Takashi. "Atmospheric Pressure Dependence of Rotation Speeds of a Motor Composed of Resonating Crystalline Quartz." Japanese Journal of Applied Physics 35, Part 1, No. 3 (March 15, 1996): 1814–17. http://dx.doi.org/10.1143/jjap.35.1814.

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Marlot, A., and J. Vedel. "Electrodeposition of Copper‐Selenium Compounds onto Gold Using a Rotating Electrochemical Quartz Crystal Microbalance." Journal of The Electrochemical Society 146, no. 1 (January 1, 1999): 177–83. http://dx.doi.org/10.1149/1.1391583.

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43

Grzegorzewski, A., and K. E. Heusler. "A kinetic investigation of the manganese dioxide electrode with a rotating quartz frequency balance." Journal of Electroanalytical Chemistry and Interfacial Electrochemistry 228, no. 1-2 (August 1987): 455–70. http://dx.doi.org/10.1016/0022-0728(87)80123-7.

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Santos, Lauro Cézar Montefalco de Lira, and Luís Gustavo Ferreira Viegas. "Exploring the relationships between shear zones and granites: field and microstructural data for contrasting case studies of the Borborema Province (NE Brazil)." Geologia USP. Série Científica 21, no. 2 (July 14, 2021): 3–18. http://dx.doi.org/10.11606/issn.2316-9095.v21-180579.

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We discuss meso- and microstructural features of granites closely related to strike-slip shear zones in the Borborema Province, NE Brazil. The Riacho do Icó stock is an en-cornue intrusion aged at ca. 607 Ma. Magmatic fabric is recorded in the core of the granite, whilst increasing deformation is marked by the development of mylonitic fabrics towards the Afogados da Ingazeira shear zone, including magmatic foliation and lineation rotation. Early recrystallization of quartz and K-feldspar crystals is widespread as a fabric with well-developed granoblastic polygonal textures and lobate subgrain boundaries, heterogeneously deformed lenses and ameboid quartz ribbons, typical of igneous rocks submitted to deformation in deep crustal levels. On the other hand, the Espinho Branco-Santa Luzia leucogranitic belt is hosted along the Patos Lineament, aged between the ca. 575 – 565 Ma interval. These rocks show discordant relationships with the host migmatites and the main deformational fabric is characterized by a dominant magmatic foliation that is locally overprinted by structures that are typical of solid-state flow. Quartz melt pockets and interstitial quartz grains filling fractures in feldspar clasts are common. Such characteristics are compatible with granites that were injected in the continental crust along planar anisotropies (i.e., shear zones) formed during the late-stage partial melting events that originated the migmatites of the area. The case studies are proxies in the understanding of different episodes of magma emplacement along shear zones in this part of West Gondwana.

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Maison, Bruce F., and Kazuhiko Kasai. "Analysis of Northridge Damaged Thirteen-Story WSMF Building." Earthquake Spectra 13, no. 3 (August 1997): 451–73. http://dx.doi.org/10.1193/1.1585957.

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The case study building experienced moment connection fractures and has instructure recorded response. Correlative analyses are performed using a probability approach to describe the connection rotational capacities. The Northridge calibrated model is then subjected to other scenario earthquake records. The main points include: -Northridge connection damage can be reasonably simulated using models that idealize the rotation capacities as random variables, -Many of the connection fractures occurred from beam moment demands that were less than the beam yield moments, -Vertical earthquake excitation and gravity loads did not play a major role in the connection fractures, -The damaged building can withstand another Northridge intensity quake, -Near-source ground motions from great quakes have the potential to collapse the building with pre-Northridge type connection details, and -Connection rotation capacity can make the difference between building survival or collapse during severe quakes.

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García-Serrano, J., N. Koshizaki, T. Sasaki, G. Martínez-Montes, and U. Pal. "Determination of optical constants of Si/ZnO polycrystalline nanocomposites by spectroscopic ellipsometry." Journal of Materials Research 16, no. 12 (December 2001): 3554–59. http://dx.doi.org/10.1557/jmr.2001.0487.

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The optical constants of Si/ZnO composite films grown on quartz glass substrates were determined in the spectral range 1.5–5.0 eV by spectroscopic ellipsometry using a rotating-analyzer ellipsometer. The structure of the samples was modeled by a two-phase (substrate–film) model, and the optical functions of the film were parameterized through different effective medium approximations. The results allowed us to estimate the microstructural film parameters, such as film thickness, the volume fractions of each of the constituents, and optical constants.

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Chan, Hong-Mo, and Sheung Tsun Tsou. "The framed Standard Model (I) — A physics case for framing the Yang–Mills theory?" International Journal of Modern Physics A 30, no. 30 (October 28, 2015): 1530059. http://dx.doi.org/10.1142/s0217751x15300598.

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Introducing, in the underlying gauge theory of the Standard Model, the frame vectors in internal space as field variables (framons), in addition to the usual gauge boson and matter fermions fields, one obtains: the standard Higgs scalar as the framon in the electroweak sector; a global [Formula: see text] symmetry dual to colour to play the role of fermion generations. Renormalization via framon loops changes the orientation in generation space of the vacuum, hence also of the mass matrices of leptons and quarks, thus making them rotate with changing scale [Formula: see text]. From previous work, it is known already that a rotating mass matrix will lead automatically to: CKM mixing and neutrino oscillations, hierarchical masses for quarks and leptons, a solution to the strong-CP problem transforming the theta-angle into a Kobayashi–Maskawa phase. Here in the framed standard model (FSM), the renormalization group equation has some special properties which explain the main qualitative features seen in experiment both for mixing matrices of quarks and leptons, and for their mass spectrum. Quantitative results will be given in Paper II. The present paper ends with some tentative predictions on Higgs decay, and with some speculations on the origin of dark matter.

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Graziani, Riccardo, Chiara Montomoli, Salvatore Iaccarino, Luca Menegon, Laura Nania, and Rodolfo Carosi. "Structural setting of a transpressive shear zone: insights from geological mapping, quartz petrofabric and kinematic vorticity analysis in NE Sardinia (Italy)." Geological Magazine 157, no. 11 (April 20, 2020): 1898–916. http://dx.doi.org/10.1017/s0016756820000138.

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AbstractThe Posada–Asinara Line is a crustal-scale transpressive shear zone affecting the Variscan basement in northern Sardinia during Late Carboniferous time. We investigated a structural transect of the Posada–Asinara Line (Baronie) with the aid of geological mapping and structural analysis. N-verging F2 isoclinal folds with associated mylonitic foliation (S2) are the main deformation features developed during the Posada–Asinara Line activity (D2). The mineral assemblages and microstructures suggest that the Posada–Asinara Line was affected by a retrograde metamorphic path. This is also confirmed by quartz microstructures, where subgrain rotation recrystallization superimposes on grain boundary migration recrystallization. Crystallographic preferred orientation data, obtained using electron backscatter diffraction, allowed analysis of quartz slip systems and estimation of the deformation temperature, vorticity of flow and rheological parameters (flow stress and strain rate) during the Posada–Asinara Line activity. Quartz deformation temperatures of 400 ± 50 °C have been estimated along a transect perpendicular to the Posada–Asinara Line, in agreement with the syn-kinematic post-metamorphic peak mineral assemblages and the late microstructures of quartz. The D2 phase can be subdivided in two events: an early D2early phase, related to the metamorphic peak and low kinematic vorticity (pure shear dominated), and a late D2late phase characterized by a lower metamorphic grade and an increased kinematic vorticity (simple shear dominated). Palaeopiezometry and strain rate estimates associated with the D2late deformation event showed an intensity gradient increasing towards the core of the shear zone. The D2early deformation developed under peak temperature conditions, while the D2late event was active at shallower structural levels.

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Eden, M. A. "An approach to the abrasion testing of individual pieces of construction materials." Geological Society, London, Engineering Geology Special Publications 13, no. 1 (1998): 193–96. http://dx.doi.org/10.1144/gsl.eng.1998.013.01.16.

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AbstractThis paper briefly introduces the basis of abrasion testing and suggests a rapid and simple test that allows the abrasion resistance of specific materials to be evaluated. Small, individual pieces of rock, mortar, or concrete can be tested and the method has been used to evaluate the potential for surface abrasion of concrete surfaces. Many of the commonly used test methods for measuring abrasion resistance of construction materials are aggregate tests such as the QMW mill abrasion test and the ASTM Los Angeles abrasion test which measure the combined resistance of a material to impact and abrasion. Other tests such as the aggregate abrasion and polished stone value tests require a smaller numberof resin mounted aggregate pieces to be studied. The ASTM surface abrasion test for concrete uses physically large flat test pieces. Like the ASTM test, the test method described in this paper measures only the abrasion resistance. However, it provides a means of comparing the abrasion resistance of small pieces of construction material and introduces quartz as a reference material.The test uses a mixture of oil and carborundum as a grinding medium with 10 mm square test pieces held by a standard load against a rotating steel lapping wheel in a rotating jig. The results are expressed as a ratio of the abrasion rate of the test material to that of quartz tested in the same way. This comparative approach enables the test to be carried out using equipment of various designs.

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TREPMANN, C. A., and B. STÖCKHERT. "Microfabric of folded quartz veins in metagreywackes: dislocation creep and subgrain rotation at high stress." Journal of Metamorphic Geology 27, no. 8 (October 2009): 555–70. http://dx.doi.org/10.1111/j.1525-1314.2009.00842.x.

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Journal articles on the topic 'Quarts rotatifs'

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