Thermal stresses in a box structure

This interim note presents an analysis, using an energy method, of the thermal stresses in a finite length box structure resulting from uniform skin heating. The solution depends upon an eighth order differential equation with constant coefficients. Numerical solutions are given for comparison with existing and projected experiment

The double and single shear strengths of avdel light alloy blind rivets in DTD 546 b aluminium alloy sheet

Tests have been performed to compare the double- and single-shear strengths of joints in DTD 546b light alloy sheets using Avdel blind rivets. The tests were an extension of work done on solid rivets, and followed conventional procedures. The double-shear proof and ultimate strengths were found to be appreciably better than the single-shear strengths over a useful range of sheet thickness/rivet diameter ratio. The effect of manufacturing tolerance was examined and found to be important, though adherence to the rivet manufacturer’s recommended procedures ensures good strength. The above conclusions lead to a consideration of the physical behaviour of the joints which is seen to differ in three ranges of thickness/diameter ratio

Space station integrated wall damage and penetration damage control. Task 5: Space debris measurement, mapping and characterization system

The procedures and results of a study of a conceptual system for measuring the debris environment on the space station is discussed. The study was conducted in two phases: the first consisted of experiments aimed at evaluating location of impact through panel response data collected from acoustic emission sensors; the second analyzed the available statistical description of the environment to determine the probability of the measurement system producing useful data, and analyzed the results of the previous tests to evaluate the accuracy of location and the feasibility of extracting impactor characteristics from the panel response. The conclusions were that for one panel the system would not be exposed to any event, but that the entire Logistics Module would provide a modest amount of data. The use of sensors with higher sensitivity than those used in the tests could be advantageous. The impact location could be found with sufficient accuracy from panel response data. The waveforms of the response were shown to contain information on the impact characteristics, but the data set did not span a sufficient range of the variables necessary to evaluate the feasibility of extracting the information

Grammatical Complexity in the Sanctuary Engravings at Les Trois-Frères

The figurative depictions from the Magdalenian parietal art of Les Trois-Frères cave have been used as a small investigative sample to analyse the presence of grammatical structures that may underpin the 97 animal representations from the four panels studied. A database of measurements was created for the anatomical dimensions of each representation and their respective categories of species, orientation, behaviour, panel and completeness. Very few combinations of co-occurrences that would have constituted a grammatical structure were found through a panel-by-panel analysis of the data. The dominant trends overall were that most were engraved by artists/authors who had a dominant right hand. This included both instances of anthropomorphs (one of which being the famous ‘sorcerer’) and dangerous or powerful beings depicted throughout the panels (bear and rhinoceros). Because grammar could not be found through statistical analysis, an alternative hypothesis as to what produced variations in the cave’s art was put forward, examining the engravings from a more aesthetic perspective. This introduced the idea that the negative space of a ‘central animal’ was being appropriated and respected by multiple depictions around it, putting forward the case that aesthetic interactions between animals were effecting multiple dimensions of their depictions

Reference to index of L.L Dobson : Duff on jurisprudence

Louis Lempriere Dobson (1871-1934) studied jurisprudence at Oxford University , under H. Duff, and graduated B.A. He was admitted a barrister of the Middle Temple, London, in 1894 and admitted as lawyer in Hobart in 1895. he was in practice with the firm of Dobson, Mitchell and Allport

Space station integrated wall design and penetration damage control. Task 4: Impact detection/location system

A program to develop a methodology is documented for detecting and locating meteoroid and debris impacts and penetrations of a wall configuration currently specified for use on space station. Testing consisted of penetrating and non-penetrating hypervelocity impacts on single and dual plate test configurations, including a prototype 1.22 m x 2.44 m x 3.56 mm (4 ft x 8 ft x 0.140 in) aluminum waffle grid backwall with multilayer insulation and a 0.063-in shield. Acoustic data were gathered with transducers and associated data acquisition systems and stored for later analysis with a multichannel digitizer. Preliminary analysis of test data included sensor evaluation, impact repeatability, first waveform arrival, and Fourier spectral analysis

Macquarie Harbour Reports & Returns 1846-47 Index: Royal Society Collection

Thomas James Lempriere (1796-1852), public official, author and artist served as Commissariat at Sarah Island (1827–30) - copies of reports on provisions and work of prisoners sent to get huon pine etc, addressed to George Maclean, Deputy- Commissary-General dated 18 June 1846 - 26 October 1847 .Letters of 18 & 26 October 1846 report arrival, the inadequate habitation (houses having been burnt down) & prisoners refusal to work on building store huts etc.only getting timber, & on being refused tobacco ration until store hut built attacked military. April 1846 - October 1847 Daily strength Register, Military establishment & Convict passholders RS 7

Copies of letters from Thomas James Lempriere to George Maclean from Macquarie Harbour and Daily Strength Register of the troops stationed there, Van Diemen's Land, 1846-7

Copies of letters from Thomas James Lempriere (1796-1852) public official, author and artist who served as Commissariat at Sarah Island (1827–30) to George Maclean, Deputy- Commissary-General, from Sarah Island, Macquarie Harbour, Van Diemen's Land, dated 18 June 1846-26 Oct 1847, reporting provisions and work of the prisoners sent to get huon pine etc. The letters of the 18 and 26 October 1846 report arrival, inadequate habitation (houses having been burnt down) and prisoners refusal to work on building. The second document is a Daily Strength Register of the troops stationed at the Military Establishment, Macquarie Harbour, April 1846-Oct 1847 including a list of Convict passholders. RS78/1-

Computational Infrared Spectroscopy of 958 Phosphorus-Bearing Molecules

Phosphine is now well-established as a biosignature, which has risen to prominence with its recent tentative detection on Venus. To follow up this discovery and related future exoplanet biosignature detections, it is important to spectroscopically detect the presence of phosphorus-bearing atmospheric molecules that could be involved in the chemical networks producing, destroying or reacting with phosphine. We start by enumerating phosphorus-bearing molecules (P-molecules) that could potentially be detected spectroscopically in planetary atmospheres and collecting all available spectral data. Gaseous P-molecules are rare, with speciation information scarce. Very few molecules have high accuracy spectral data from experiment or theory; instead, the best current spectral data was obtained using a high-throughput computational algorithm, RASCALL, relying on functional group theory to efficiently produce approximate spectral data for arbitrary molecules based on their component functional groups. Here, we present a high-throughput approach utilizing established computational quantum chemistry methods (CQC) to produce a database of approximate infrared spectra for 958 P-molecules. These data are of interest for astronomy and astrochemistry (importantly identifying potential ambiguities in molecular assignments), improving RASCALL's underlying data, big data spectral analysis and future machine learning applications. However, this data will probably not be sufficiently accurate for secure experimental detections of specific molecules within complex gaseous mixtures in laboratory or astronomy settings. We chose the strongly performing harmonic ωB97X-D/def2-SVPD model chemistry for all molecules and test the more sophisticated and time-consuming GVPT2 anharmonic model chemistry for 250 smaller molecules. Limitations to our automated approach, particularly for the less robust GVPT2 method, are considered along with pathways to future improvements. Our CQC calculations significantly improve on existing RASCALL data by providing quantitative intensities, new data in the fingerprint region (crucial for molecular identification) and higher frequency regions (overtones, combination bands), and improved data for fundamental transitions based on the specific chemical environment. As the spectroscopy of most P-molecules have never been studied outside RASCALL and this approach, the new data in this paper is the most accurate spectral data available for most P-molecules and represent a significant advance in the understanding of the spectroscopic behavior of these molecules.</jats:p

Homogenized stiffness matrices for mineralized collagen fibrils and lamellar bone using unit cell finite element models

Mineralized collagen fibrils have been usually analyzed like a two phase composite material where crystals are considered as platelets that constitute the reinforcement phase. Different models have been used to describe the elastic behavior of the material. In this work, it is shown that, when Halpin-Tsai equations are applied to estimate elastic constants from typical constituent properties, not all crystal dimensions yield a model that satisfy thermodynamic restrictions. We provide the ranges of platelet dimensions that lead to positive definite stiffness matrices. On the other hand, a finite element model of a mineralized collagen fibril unit cell under periodic boundary conditions is analyzed. By applying six canonical load cases, homogenized stiffness matrices are numerically calculated. Results show a monoclinic behavior of the mineralized collagen fibril. In addition, a 5-layer lamellar structure is also considered where crystals rotate in adjacent layers of a lamella. The stiffness matrix of each layer is calculated applying Lekhnitskii transformations and a new finite lement model under periodic boundary conditions is analyzed to calculate the homogenized 3D anisotropic stiffness matrix of a unit cell of lamellar bone. Results are compared with the rule-of-mixtures showing in general good agreement.The authors acknowledge the Ministerio de Economia y Competitividad the financial support given through the project DPI2010-20990 and the Generalitat Valenciana through the Programme Prometeo 2012/023. The authors thank Ms. Carla Gonzalez Carrillo by her help in the development of some of the numerical models.Vercher Martínez, A.; Giner Maravilla, E.; Arango Villegas, C.; Tarancón Caro, JE.; Fuenmayor Fernández, FJ. (2014). Homogenized stiffness matrices for mineralized collagen fibrils and lamellar bone using unit cell finite element models. 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