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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

The influence of mycelial morphology on the ability of "Streptomyces" species to produce antibiotics in liquid culture

Pickup, Karen Marie January 1990 (has links)
No description available.
202

Strategic analysis of organisational decision-making as the interface between corporate idiosyncracies and the adoption of technological innovations : the case of business information systems

Morieux, Yves V. H. January 1986 (has links)
This research aims at helping industrial innovators convert technological achievement into economic success. The underlying axiom of the study is that the likelihood of a commercial "big hit" is a direct function of the adaptation of selling efforts to the potential customers' idiosyncracies. This raises theoretical, epistemological and practical questions. Theoretically, the problem is to identify a conceptual framework within which organisational idiosyncracies can be understood and defined. Epistemologically, the problem is to identify a methodological basis on which these indiosyncracies can be assessed and tested as to their influence on the adoption of industrial innovations. Practically, the problem is to identify an operational marketing approach in which this type of influence can be taken into account and exploited. The theoretical problem is solved in meta techno-economic terms. The concept of organisational climate is used to encompass the various corporate idiosyn cracies under attention. The epistemological problem is solved by applying strategic analysis to decision-making processes related to the adoption of new information technologies. Concepts such as organisational rationalities, strategies, stakes, zones of uncertainty and coalitions are found to explain and account for the influence of corporate idiosyncracies on decision processes in three large (or multinational) French companies faced with commercial proposals to adopt computer-based business information systems. The practical problem is solved by proposing a design to assess idiosyncratic strategic factors in target organisations and by suggesting how commercial approaches can be developed accordingly. The research solutions are bounded by three limits: the respective influence of strategic factors as opposed to other organisational idiosyncracies was empirically untestable; the validity of the conclusions is highly dependent on the field which was investigated (any a priori generalisation to non-informatic innovations is thus problematic); and lack of information may constrain assessment of strategic factors.
203

Stability of heterologous genetic material in Lactococci

Moorhouse, Simon David January 1992 (has links)
No description available.
204

Chemistry of 1,3,5-tris (trimethylsiloxy) -1-methoxyhexa-1,3,5-triene

Stössel, Daniel. January 1987 (has links)
The title compound was synthesized and its chemistry studied for the first time. It reacts with carbon electrophiles initially at its $ epsilon$-position. The condensation with aliphatic imidazolides or similar acylating agents furnished methyl 6-alkyl-2,4-dihydroxy benzoates in a 5C + 1C fashion. Reaction with aromatic imidazolides, also in a 5C + 1C manner, gave unsymmetrical biphenyls with the 2-carbomethoxy-3,5-dihydroxyphenyl moiety. A regiocontrolled synthesis of naphthalene derivatives was developed by reaction with the appropriate 1,3,5-tris-electrophiles in a 5C + 5C fashion.
205

Potential competition and multi-product activity

Mahabir, Dhanayshar January 1994 (has links)
This thesis stresses the existence of a fundamental link between potential competition and multi-product activity. Potential competitors are identified as already-existing firms that possess "latent capacity", a principal source of scope economies, which enable firms to expand or alter their product portfolio in the short period. When latent capacity is accompanied by certain sunk costs, hit-and-run entry becomes profitable as the "latent competitor" is able to easily surmount the major barriers to entry, avoid the disadvantages in cost associated with small batch production, and exit cheaply from the various markets. This new theory of potential competition further demonstrates that when framed within a multi-product environment, the major criticisms that are levelled against the theory of contestability can be addressed. Additionally, it shows how the age-old conundrum of increasing returns and competitive behaviour may be reconciled. Empirical evidence confirms the existence of latent capacity. Such capacity is embodied in the Flexible Manufacturing Systems (FMS) and flexible manpower resources that are increasingly being employed by firms.
206

Quantitative gas chromatographic analysis of synthetic dairy culture flavors

Walradt, John Pierce, 1942- 04 May 1967 (has links)
The development of synthetic culture flavors for use in dairy products such as sour cream, cottage cheese, butter, and buttermilk has created the need for a rapid quantitative analysis for the synthetic flavor concentrates. An internal standard gas chromatographic method has been developed which is capable of +10% accuracy for each flavor compound in single sample analyses. The separation of water, acetaldehyde, dimethyl sulfide, acetic acid, diacetyl, propylene glycol, and acetone (the internal standard) was performed with a column consisting of a 1/8 inch OD section of stainless steel tubing 10 feet in length packed with 120-150 mesh Porapak Q plus a stainless steel precolumn 1/8 inch OD and 10 inches in length packed with 120-150 mesh Porapak R. The column was operated isothermally at 155°C with a flow rate of 44 ml per min of nitrogen carrier gas. A flame ionization detector was used. In the course of the investigation, Porapak Q (available from Waters Associates Inc., Framingham, Mass.) was evaluated. The optimum mesh size under the conditions employed was the 120-150 mesh range. The efficiency of Porapak Q columns, as reflected by the number of theoretical plates per foot for n-propanol and the resolution of n-propanol and iso-propanol, was found to increase when the column diameter was increased from 1/16 inch OD to 1/8 inch OD to 1/4 inch OD. / Graduation date: 1967
207

Actaldehyde production and utilization by lactic cultures

Keenan, Thomas William 29 September 1965 (has links)
Acetaldehyde is known to be responsible for the green or yogurt-like flavor defect of lactic cultures. This study was undertaken to extend the knowledge of acetaldehyde production and utilization by microorganisms normally found in mixed-strain butter cultures. It is anticipated that the resulting information will contribute to a more thorough understanding of the development of a green flavor defect; hence, to methods of avoiding and overcoming this defect. Acetaldehyde production by single-strain cultures of S. lactis, S. cremoris, and S. diacetilactis was found to parallel the increase in microbial population. S. lactis and S. cremoris were found to remove some of the acetaldehyde produced on continued incubation at 21°C. S. diacetilactis did not remove any of the acetaldehyde produced. The ratio of diacetyl to acetaldehyde in the strains of S. diacetilactis studied was found to be unfavorable for a good culture flavor at all times up to 22-24 hr incubation. All of the cultures studied produced a distinct green flavor when grown in milk media. All of the lactic streptococci studied produced both ethanol and acetone when grown in a boiled milk medium. No evidence of acetone utilization by S. diacetilactis was observed. A tentative mechanism for the formation of acetone from pyruvate via acetoacetate was proposed. Single-strain cultures of Leuconostoc dextranicum and Leuconostoc mesenteroides were shown to be capable of utilizing added acetaldehyde under a variety of culturing conditions. These two organisms, along with L. citrovorum were combined into two-strain mixtures with various lactic streptococci. The production and utilization of acetaldehyde varied widely among different two-strain mixtures. The ratio of different lactic organisms comprising the flora of a desirably flavored commercial mixed-strain butter culture was determined. The microbial shift occurring when this culture developed a green flavor defect was found to be an overgrowth of the homo-fermentative lactic streptococci by the S. diacetilactis population. It was found that the concentration of acetaldehyde in a ripened single-strain lactic culture could be significantly reduced by adding a large inoculum of a culture of L. citrovorum and continuing incubation at 21°C or by cooling and holding the culture at 5°C after the addition of L. citrovorum. / Graduation date: 1966
208

Pectin in tomatoes as a protective colloid for casein

Paasche, Bette Marie 14 May 1963 (has links)
The purpose of this investigation was to study the role of pectin in protecting casein from coagulation by heat and acid during the preparation of tomato soup. Three varieties of tomatoes were used for the study, Ace, Improved Garden State and Campbell 146, and each variety was processed two ways, by heating the tomatoes rapidly to 100°C before juicing (hot break) and by holding the mascerated tomatoes for 30 minutes before heating (cold break). Juice of the Ace variety had the highest pH and Campbell 146 the lowest by both processing methods. In all cases, cold break juice had lower pH values than did the hot break juice. Proportion of serum to solids resulting from centrifugation of a sample of each juice was used as one index to the amount of degradation of the pectin. The amount of solids in the cold break juice was less than the amount of solids in the hot break juice. Serums from juices prepared by the hot break method were more viscous than those by the cold break method. Of the hot break juices, Improved Garden State was the most viscous and Campbell 146 the least. The concentration of pectin in the serums of juices prepared by the cold break method was from one-third to one-half that in serums of juices by the hot break method. Juices of the three varieties of tomatoes by both methods of processing were combined with reconstituted non-fat milk and heated as for tomato soup. Curdling was assessed by measuring the nitrogen in the filtrate by the micro-Kjeldahl method. Juices of Ace, the low acid variety, caused the least amount of curdling. Of the four juices from the two more acid varieties, Campbell 146 by the cold break method had the lowest concentration of pectin in the serum and the soup curdled most, while Improved Garden State by the hot break method was highest in pectin and resulted in the least curdling of the soup. Juice from Campbell 146 by the cold break method was the most acid of the four and that of Improved Garden State by the hot break method was the least acid. When an amount of high-methoxy pectin equal to the difference between the concentration of pectin in the cold break and that in the hot break juices of the Improved Garden State variety was added to a sample of the juice before making soup, curdling was less than when untreated juice was used, and the pH was slightly higher. Thus any protective effect that pectin might have had. on the casein was clouded by differences in the pH values of the juices. Pectin possibly has a role in protecting the casein, but the acidity certainly is the determining factor in the coagulation of casein in the preparation of tomato soup. / Graduation date: 1963
209

Canning of fish in oil spiced according to Indian taste

Parpia, Husain Ali Bhimjee 02 1900 (has links)
Graduation date: 1948
210

The role of dihydroquercetin as an antioxidant for some dairy products

Rajan, Thillasthanam Seshadri 08 November 1961 (has links)
Graduation date: 1962

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