Heavy oil and oil sands deposits constitute an important resource, with in-place estimates varying between 600 × 109and 980 × 109m3. These deposits are mostly concentrated in Canada, the US and Venezuela. Th...
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Heavy oil and oil sands deposits constitute an important resource, with in-place estimates varying between 600 × 109and 980 × 109m3. These deposits are mostly concentrated in Canada, the US and Venezuela. The gradual depletion of conventional oil reserves is leading to a greater interest in heavy oil *** paper presents on overview of heavy oil characteristics, worldwide deposits and recovery methods, with special emphasis on the heavy oils and oil sands of Canada. Thermal recovery techniques such as cyclic steam stimulation, steamflooding and in-situ combustion have been generally more successful than non-thermal methods. The principal thermal recovery processes are discussed in detail. Reservoir characteristics influencing the applicability of these processes are mentioned, and possible operational problems are *** of the Canadian heavy oils and oil sands deposits occur in the provinces of Alberta and Saskatchewan. Selected recovery projects currently in operation are described, outlining modifications to the basic process, problems encountered and range of success.
The enzymatic profiles of 109 clinical isolates ofAcinetobacter calcoaceticus *** andlwoffi were determined with conventional plate tests and the rapid API ZYM system (Analytab Products, Plainview, N.Y.). The majority...
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The enzymatic profiles of 109 clinical isolates ofAcinetobacter calcoaceticus *** andlwoffi were determined with conventional plate tests and the rapid API ZYM system (Analytab Products, Plainview, N.Y.). The majority of strains tested lacked DNase, hemolysin, protease, elastase and gelatinase. Strong enzymatic activities of butyrate esterase (C4), caprylate esterase (C8) and leucine arylamidase were detected in all isolates. No trypsin, chymotrypsin, alkaline phosphatase or glucosidase activities were present. This profile was characteristic of all isolates examined by the API ZYM system and could serve as a useful diagnostic feature ofAcinetobacter calcoaceticus *** and ***.
A total of 450 yeast isolates were obtained from up to 34 sites on 59 human subjects. The yeasts were characterized using morphological features and assimilation tests. Ten species were identified but, of these, Candi...
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A total of 450 yeast isolates were obtained from up to 34 sites on 59 human subjects. The yeasts were characterized using morphological features and assimilation tests. Ten species were identified but, of these, Candida albicans and C. parapsilosis were the most common and accounted for 84% of the isolates. An examination of the biotypes of the various species indicated a much greater diversity in the yeast microflora than that detected by species identifications alone. Fifty-five biotypes were differentiated and it is suggested that these could be regarded as distinct taxonomic or ecological entities.
On the occasion of commenting on the definitions of guṇas in the Nāṭyaśāstra, Abhinavagupta gives a full analysis of the scheme of twenty guṇas in Vāmana's Kāvyālaṃkārasūtravṛtti. A comparison of Vāmana...
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On the occasion of commenting on the definitions of guṇas in the Nāṭyaśāstra, Abhinavagupta gives a full analysis of the scheme of twenty guṇas in Vāmana's Kāvyālaṃkārasūtravṛtti. A comparison of Vāmana's and Abhinavagupta's treatments of the guṇas pertaining to phonetic texture solves a number of problems in both texts: reference to Vāmana's remarks corrects several corrupt readings in the Abhinavabhāratī, and Abhinavagupta explains with greater precision than any other commentator the relevance of Vāmana's examples to his definitions, bringing out the importance of the relative aspects of the arrangement of sounds, and of transitions between different patterns of arrangement.
We characterize the class $CG(s)$ of matrices A for which the linear system $A{\bf x} = {\bf b}$ can be solved by an s-term conjugate gradient method. We show that, except for a few anomalies, the class $CG(s)$ consis...
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We characterize the class $CG(s)$ of matrices A for which the linear system $A{\bf x} = {\bf b}$ can be solved by an s-term conjugate gradient method. We show that, except for a few anomalies, the class $CG(s)$ consists of matrices A for which conjugate gradient methods are already known. These matrices are the Hermitian matrices, $A^ *= A$, and the matrices of the form $Ae^{i\theta} (dI + B)$, with $B^ *= - B$.
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