| Enumeration of Large Combinatorial Structures |
JUN 1981 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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 | A good approximation is found to the number of non-separable sparsely edged labelled graphs, relevant in application in statistical mechanics. The enumeration of smooth labelled graphs, where we obtain an exact form for the exponential generating function, find the differential equation it satisfies and a combinatorial interpretation of this equation and finally study the sparsely edged case. We remark on a surprisingly close relationship between the results for the sparsely ... |
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| Studies of Soil Organic Matter Using Formic Acid Solvents: Factors Affecting Composition and Degree fo Formylation of Organic Isolates |
MAR 1981 |
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| Authors:
A. H. Sinclair; J. Tinsley; ABERDEEN UNIV (SCOTLAND)
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| Two soils were extracted under reflux with formic acid H2O for 0.25 h, followed by formic acid/HF for 0.25 h. In one set of experiments 14C-labelled formic acid was used in the first extraction and unlabelled formic acid in the second: in a second set this labelling sequence was reversed. After separation from the soil residues, the soil extracts were further refluxed for up to 3.75 h. Organic matter was ... |
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| Soil Segment Overlap in Character Space and Its Implications for Soil Classification |
MAR 1981 |
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| Authors:
R. Webster; A. B. McBratney ; ABERDEEN UNIV (SCOTLAND)
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| A major problem in soil classification for soil survey is the lack, or uncertainty, of correspondence between mapping units in different localities. The problem is examined using multivariate soil data recorded at short regular intervals along transects in Oxfordshire and Aberdeenshire. The data for each transect were transformed to cononical variates, the first two of which were then used to locate soil boundaries and to show the relationships among the ... |
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| A Study of Vibratory Driving in Granular Soils |
SEP 1980 |
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| Authors:
A. A. Rodger; G. S. Littlejohn; ABERDEEN UNIV (SCOTLAND)
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| Weathering in Tertiary Gravels in N. E. Scotland |
SEP 1980 |
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| Authors:
A. J. Koppi; E. A. Fitzpatrick; ABERDEEN UNIV (SCOTLAND)
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| The weathering of highly quartzose flint-containing gravels, believed to be the remnants of Tertiary beach deposits in N.E. Scotland, has been studied in detail. The deposits also contain infrequent boulders of granite, quartz schists and granulites which are largely kaolinised, but the kaolin varies in crystallinity between the two sites investigated. Quartz, alkali feldspars, muscovite and biotite-like mica have been variously altered, and the weathering products include fine grained silica ... |
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| Use of the Drop-Cone Penetrometer on Undisturbed and Remoulded Soils at a Range of Soil-Water Tensions |
MAR 1980 |
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| Authors:
C. E. Mullins; A. Fraser; ABERDEEN UNIV (SCOTLAND)
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| Drop-cone measurements were made on undisturbed and remoulded samples of top-and sub-soil from two sites equilibrated at tensions between zero and 600 kPa (6 bar). All samples remained virtually saturated up to the highest tension. Within a few days after remoulding, cone penetration values had returned to those obtained on undisturbed samples. (AA) |
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| The Origin of the Red Mediterranean Soils in Epirus, Greece |
MAR 1980 |
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| Authors:
D. A. Macleod; ABERDEEN UNIV (SCOTLAND)
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| To determine the contribution of limestone weathering to soil formation insoluble residues of 6 samples of the Pantokraton limestone were separated by treatment with 2m acetic acid at pH 3. The mean insoluble residue content is only 0.15% and to produce a soil depth of 40 cm it has been calculated that about 130 m of limestone would have to be weathered. No correspondence was found between the particle size ... |
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| The Impregnation of Wet Peat for the Production of Thin Sections |
DEC 1979 |
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| Authors:
E. A. Fitzpatrick; T. Gudmundsson; ABERDEEN UNIV (SCOTLAND)
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| A technique is described to replace the water in peat by acetone prior to impregnation with resin. The peat is exposed to the vapour of aqueous acetone of increasing concentration up to 100 percent acetone. After impregnation with resin, high quality thin sections can be obtained. (AA) |
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| Soil Organic Matter Studies: Extraction with Formic Acid/Dimethyl Sulphoxide Mixtures and Fractionation with Zr(IV) |
JUN 1979 |
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| Authors:
M. G. Kibblewhite; J. Tinsley; ABERDEEN UNIV (SCOTLAND)
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| Mixtures of the dipolar organic solvents formic acid (FA) and dimethyl sulphoxide (DMSO) were used to extract organic matter from soils. At 100 C optimum extraction from a calcareous clay loam was with 80/20 v/v FA/DMS0 corresponding to a maximum in dielectric constant. Extration of seven soils with boiling FA/H20(107 C) and FA/DMSO (112 C) indicated that similar amounts of C and N are generally dissolved by the two solvent ... |
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| Errors in Measuring Uniform Aeolian Sand Flow by Means of an Adjustable Trap |
JUN 1979 |
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| Authors:
J. R. Jones /B. B. /Willetts; ABERDEEN UNIV (SCOTLAND)
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| A vertical-slot sand trap was constructed incorporating a device to adjust the freedom of flow through the trap. Using a dune-sand of equivalent diameter 0.25 mm, measurements of sand transport were made with this flow so adjusted that no change of sand surface geometry detectable by eye occurred upstream of the trap; this was considered to be a correct procedure. Further measurements were taken with the flow through the trap ... |
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| Enumeration of Large Combinatorial Structures. |
NOV 1977 |
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| Authors:
Edward M. Wright; ABERDEEN UNIV (SCOTLAND)
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| New results are given about the number of 2-connected labelled (n,q) graphs, i.e. graphs on n points and q lines, including a combinatorial interpretation of Temperley's differential equation satisfied by the exponential generating function of this number (applicable in Statistical Mechanics). This leads to two methods for finding asymptotic approximations to this number. A curious paradox is found in the asymptotic enumeration of unlabelled graphs. Work was continued on connected, ... |
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| Enumeration of Large Combinatorial Structures. |
NOV 1976 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| Two methods are described to determine exact formulae for the number of labelled connected graphs on n points and n+k edges for general n and different values of k. One method supplies an essential piece of information for general k; given this, the other is much more efficient and is well-adapted to machine computation. The first method is extended to several other problems but has to replace the second by ... |
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| Intelligence in a Democracy, |
13 JAN 1976 |
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| Authors:
R. V. Jones; ABERDEEN UNIV (SCOTLAND)
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| Enumeration of Large Combinatorial Structures. |
Nov 1975 |
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| Authors:
E M Wright; ABERDEEN UNIV (SCOTLAND)
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| The author developed a recurrence method to obtain an exact formula for successive k for the number of graphs with n labelled nodes and n+k edges. Asymptotic results follow for large n. He also gives an account, including several new results, of the asymptotic enumeration theory for unlabelled (n,q) graphs which he developed over the last few years. A detailed proof is given of results about the probability of a ... |
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| Asymptotic Problems in Graph Theory. |
NOV 1974 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| An (n,q) graph is one with n nodes and q edges. It is shown that the asymptotic probability that an (n,q) graph is Hamiltonian is the same whether it is labelled or unlabelled. Again the strict probability for the unlabelled case can decrease as q increases in a certain interval, but not for the labelled case. Dr. Sheehan and the author find a general formula for the number of Hamiltonian ... |
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| A Technique of Field Permeability Testing Employing a Single Packer Suspended by Wire Line |
SEP 1974 |
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| Authors:
T. R. Harper; ABERDEEN UNIV (SCOTLAND)
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| A technique is proposed whereby falling head tests, in the cavity formed between the surface casing and a single packer suspended in the borehole by wire line, generate a record of permeability variation for the length of drilled section. The system is independent of a drilling rig, the field equipment is inexpensive and readily portable, and test execution is expedient. The system is suitable for use in stable boreholes as ... |
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| Asymptotic Enumeration of Combinatorial Structures. |
NOV 1973 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| In a previous paper the author found and announced complete results on the asymptotic enumeration of (n,q) graphs, i.e. graphs with n unlabelled nodes and q edges. This year the proofs of these results have been shortened and simplified. The results themselves have been applied to obtain very precise theorems about the behaviour of the probability of connectedness of a graph for large fixed n as q increases. They have ... |
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| Asymptotic Enumeration of Combinatorial Structures. |
SEP 1972 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| The report completes the solution of the problem of finding an asymptotic approximation to T, the number of unlabelled graphs on n nodes with q edges, for all large value of min (q, N-q) where N = n (n-1)/2. Improvement of the bound for the error term enables making applications. It is found that the limit as n approaches infinity of B the probability of a random (n,q) graph being ... |
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| Crosslinking in styrene butadiene polymerizations. |
APR 72 |
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| Authors:
G. M. Burnett; G. G. Cameron; ABERDEEN UNIV (SCOTLAND)
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| The styrene-butadiene copolymerization was carried out in emulsion using a 1500 type recipe at 5 C. Two series of commercial samples withdrawn at various stages of a continuous reactor line were investigated. The deterioration of the processability is not dependent on the appearance of gel is demonstrated by the fact that in neither of these instances did gel appear until over 60% conversion had been achieved. (P.S.-PL) ANNOTATION: Crosslinking in ... |
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| Asymptotic Enumeration of Combinatorial Structures. |
JUN 1971 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| The paper reports an asymptotic expansion for the logarithm of the number of 'log-piles' or 'stacks' which can be built with n congruent circular cylinders. This result has applications to work of Temperley's on the calculation of the entropy of the surfaces of certain crystals. The authors find an asymptotic approximation to the number of graphs on n labelled colored nodes with just q edges for large n and any ... |
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| PROBLEMS IN PARTITION THEORY AND RELATED TOPICS. |
MAY 1970 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| The previous complicated proof by the author of the asymptotic approximation to T sub nq, the number of graphs on n unlabelled nodes with q edges has been shortened and simplified. An almost complete arithmetical theory for H sub n)(1), Euler's rencontre number, the number of permutations of n different objects in which no object remains unmoved, has been developed. The corresponding arithmetical theory and the asymptotic theory for (H ... |
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| PROBLEMS IN PARTITION THEORY AND RELATED TOPICS. |
MAY 1969 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| Contents: Asymptotic relations between enumerative functions in graph theory; The number of graphs on many unlabelled nodes; Random graphs; The number of irreducible tournaments; Asymptotic enumeration of connected graphs; Graphs on many nodes with many edges; Coloured graphs. |
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| PARTITIONS OF MULTIPARTITES (I) AND COLOURED GRAPHS WITH A LARGE NUMBER OF NODES (II). |
30 SEP 1963 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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| STRUCTURAL CHEMISTRY OF SILICATES AND RELATED SUBSTANCES |
01 SEP 1960 |
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| Authors:
H.F.W. TAYLOR; L.S. DENT GLASSER; F.P. GLASSER; ABERDEEN UNIV (SCOTLAND)
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| Studies of oriented transformations, and crystal chemistry of oxides are described. Detailed study of the oriented transformations rhodonite to wollastonite provides direct evidence of the migration of Si during thermal transformations of silicates. The results of dry heating and hydrothermal treatment of a variety of other silicates are described. Crystal chemical studies, including a number of RO-R2O3 compounds are in progress. The stability relationships of the calcium gallates are described. ... |
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| PARTITION OF MULTIPARTITE NUMBERS INTO K PARTS, |
1941 |
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| Authors:
E. M. Wright; ABERDEEN UNIV (SCOTLAND)
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