965 resultados para 2-adic complexity


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The mineral xonotlite Ca 6Si 6O 17(OH) 2 is a crystalline calcium silicate hydrate which is widely used in plaster boards and in many industrial applications. The structure of xonotlite is best described as having a dreierdoppelketten silicate structure, and describes the repeating silicate trimer which forms the silicate chains, and doppel indicating that two chains combine. Raman bands at 1042 and 1070 cm -1 are assigned to the SiO stretching vibrations of linked units of Si 4O 11 units. Raman bands at 961 and 980 cm -1 serve to identify Si 3O 10 units. The broad Raman band at 862 cm -1 is attributed to hydroxyl deformation modes. Intense Raman bands at 593 and 695 cm -1 are assigned to OSiO bending vibrations. Intense Raman bands at 3578, 3611, 3627 and 3665 cm -1 are assigned to OH stretching vibrations of the OH units in xonotlite. Infrared spectra are in harmony with the Raman spectra. Raman spectroscopy with complimentary infrared spectroscopy enables the characterisation of the building material xonotlite.

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In the structure of the title compound C14H9Cl3I2, which is the p-iodophenyl analogue of the insecticide DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], isomorphism between the two compounds has been confirmed. In the molecule the dihedral angle between the planes of the two phenyl rings is 65.8(4)deg. which compares with 64.7(7)deg. in DDT.

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In the structure of the title compound C22H27Cl302, which is the p-butoxyphenyl analogue of the insecticidally active p-methoxyphenyl compound methoxychlor, the dihedral angle between the two phenyl rings is 79.61(11)deg. Present also in the structure is an intramolecular aromatic C-H...Cl interaction [3.361(2)Ang].

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Topographic structural complexity of a reef is highly correlated to coral growth rates, coral cover and overall levels of biodiversity, and is therefore integral in determining ecological processes. Modeling these processes commonly includes measures of rugosity obtained from a wide range of different survey techniques that often fail to capture rugosity at different spatial scales. Here we show that accurate estimates of rugosity can be obtained from video footage captured using underwater video cameras (i.e., monocular video). To demonstrate the accuracy of our method, we compared the results to in situ measurements of a 2m x 20m area of forereef from Glovers Reef atoll in Belize. Sequential pairs of images were used to compute fine scale bathymetric reconstructions of the reef substrate from which precise measurements of rugosity and reef topographic structural complexity can be derived across multiple spatial scales. To achieve accurate bathymetric reconstructions from uncalibrated monocular video, the position of the camera for each image in the video sequence and the intrinsic parameters (e.g., focal length) must be computed simultaneously. We show that these parameters can be often determined when the data exhibits parallax-type motion, and that rugosity and reef complexity can be accurately computed from existing video sequences taken from any type of underwater camera from any reef habitat or location. This technique provides an infinite array of possibilities for future coral reef research by providing a cost-effective and automated method of determining structural complexity and rugosity in both new and historical video surveys of coral reefs.

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The structures of the open chain amide carboxylic acid rac-cis-[2-(2-methoxyphenyl)carbamoyl]cyclohexane-1-carboxylic acid, C15H19NO4, (I) and the cyclic imides rac-cis-2-(4-methoxyphenyl)-3a,4,5,6,7,7-hexahydroisoindole-1,3-dione,C15H17NO3, (II), chiral cis-2-(3-carboxyphenyl)-3a,4,5,6,7,7a-hexahydroisoindole-1,3-dione, C15H15NO4,(III) and rac-cis-2-(4-carboxyphenyl)- 3a,4,5,6,7,7a-hexahydroisoindole-1,3-dione monohydrate, C15H15NO4. H2O) (IV), are reported. In the amide acid (I), the phenylcarbamoyl group is essentially planar [maximum deviation from the least-squares plane = 0.060(1)Ang. for the amide O atom], the molecules form discrete centrosymmetric dimers through intermolecular cyclic carboxy-carboxy O-H...O hydrogen-bonding interactions [graph set notation R2/2(8)]. The cyclic imides (II)--(IV) are conformationally similar, with comparable phenyl ring rotations about the imide N-C(aromatic) bond [dihedral angles between the benzene and isoindole rings = 51.55(7)deg. in (II), 59.22(12)deg. in (III) and 51.99(14)deg. in (IV). Unlike (II) in which only weak intermolecular C-H...O(imide) hydrogen bonding is present, the crystal packing of imides (III) and (IV) shows strong intermolecular carboxylic acid O-H...O hydrogen-bonding associations. With (III), these involve imide O-atom acceptors, giving one-dimensional zigzag chains [graph set C(9)], while with the monohydrate (IV), the hydrogen bond involves the partially disordered water molecule which also bridges molecules through both imide and carboxyl O-atom acceptors in a cyclic R4/4(12) association, giving a two-dimensional sheet structure. The structures reported here expand the structural data base for compounds of this series formed from the facile reaction of cis-cyclohexane-1,2-dicarboxylic anhydride with substituted anilines, in which there is a much larger incidence of cyclic imides compared to amide carboxylic acids.

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The often competing imperatives of equity, simplicity and efficiency in the income tax regime, particularly the notion of simplicity, has been most evident within Australia’s small business sector over the last decade. In an attempt to provide tax simplification and reduce the tax compliance burden faced by Australian small businesses, provisions collectively referred to as the ‘simplified tax system’ or STS were introduced. The STS was designed to provide eligible small businesses with the option of adopting a range of ‘simplified’ tax measures designed to simplify their tax affairs whilst at the same time, reducing their tax compliance costs. Ultimately, a low take-up rate and accompanying criticisms led to a remodelled and rebadged concessionary regime known as the ‘Small Business Entity’ (SBE) regime which came into effect from 1 July 2007. This paper, through a pilot study, investigates the SBE regime though the eyes of the practitioner. In line the Australian Federal Government’s objective of simplification and reduced compliance costs, the purpose of the study was to (1) determine the extent to which the SBE concessions are being adopted by tax practitioners on behalf of their clients, (2) gain an understanding as to which individual SBE tax concessions are most favoured by practitioners, (3) determine the primary motivation as to why tax practitioners recommend particular SBE concessions to their clients, and (4) canvass the opinions of practitioners as to whether they believed that the introduction of the SBE concessions had met their stated objective of reducing tax compliance costs for small businesses. The findings of this research indicate that, while there is a perception that the SBE concessions are worth embracing, contrary to the policy intent, the reasons behind adopting the concessions was the opportunity to minimise a clients’ tax liability. It was revealed that adopting particular concessions had nothing to do with compliance costs savings and, in fact, the SBE concessions merely added another layer of complexity to an already cumbersome and complex tax code, which resulted in increased compliance costs for their small businesses clients. Further, the SBE concessions allowed tax practitioners the opportunity to engage in effective tax minimisation, thereby fulfilling the client advocacy role of the tax practitioner in maximising their clients’ tax preferences.

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In late 1993 the Federal Government required the Industry Commission to inquire into charitable organisations. We have previously raised issues about the scope and nature of the inquiry process. These issues are: - the appropriateness of the Commission to undertake the inquiry, - the limited time span given the breadth of the inquiry, - and the non-explicit disclosure of the intellectual framework and methodology to be employed in the inquiry.

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In the structure of the title compound, [Mg(H2O)2(C8H6FO3)2]n(0.4H2O)n, slightly distorted octahedral MgO6 complex units have crystallographic inversion symmetry, the coordination polyhedron comprising two trans-related water molecules and four carboxyl O-atom donors, two of which are bridging. Within the two-dimensional complex polymer which is parallel to (100), the coordinating water molecules form intermolecular O---H...O hydrogen-bonds with carboxylate and phenoxy O-atom acceptors, as well as with the partial-occupancy solvent water molecules.

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1. Like the Commonwealth Tax regime, state taxation legislation has now ballooned in size from the good old days when life and tax were relatively simple issues. 2. This case study of Queensland state taxation will examine the following taxes affecting churches and charities in this state: (a) Stamp Duty (b) Land Tax; and (c) Local Authority Rates 3. Each type of tax will be considered in turn. A brief legislative history of the statutory instruments governing these taxes will be given with a closer examination of the present schemes. Relevant judicial pronouncements will be considered and some open discussion of real life examples. 4. It is submitted that the regular donors to our worthy charities and the dedicated weekly churchgoers would have absolutely no idea: (a) that indirectly the value of their donations and weekly offerings are increasingly being eroded by the imposts of Government not only in terms of the amounts of those imposts but the enormous administrative burden of coping with the legislation; (b) of the complexity of the taxation legislation affecting their churches and charities; or (c) that their churches and charities are even paying taxes.