摘要:

Deposition of oral bacteria onto glass from a potassium phosphate buffered suspension has been studied in a parallel plate flow cell. Three bacterial strains with known surface free energies and zeta potentials, and two Strains(S. salivariusHB and S.salivariusHB‐C12) having well‐defined surface appendages have been employed. Polystyrene latices were included to provide a comparison with inert particles. Initial deposition rates of the various bacteria ranged from 0–1—2·9 × 103particles cm “"2sec”; ‘. The initial deposition rates have been related to an approximate theory of convective diffusion in which electrostatic interactions are omitted. A theory describing the influence of particle desorption and blocking on the deposition rate has been tested for its applicability to bacterial deposition at later stages. From the results it is concluded that a simple convective diffusion theory overestimates the experimental results, due to an increase in hydrodynamic friction of particles closely approaching the surface, which overbalances the attractive van der Waals forces. Deposition at later stages corresponded with theoretical expectations, from which a constant blocking of available adhesion sites on the surface can be concluded. Comparison of the deposition rates of particles experiencing an electrostatic potential barrier while approaching the substratum surface with those experiencing a net attractive force suggests that appendages present on the bacterial cell surface assist in deposition. Desorption is observed only during the first 5–10 seconds after deposition.

ISSN:0892-7014    

DOI:10.1080/08927018809378100

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

This paper presents a comparative study of biofouling at three sites, experiencing different environmental conditions, within a power station cooling system between September 1982 and August 1983. Microfouling and macrofouling were studied independently through the analysis of dominant species, number of species (S), diversity (H’), and evenness (J‘). The degree of affinity among samples was calculated through Czekanowski's Index and a multivariate method was applied to analyse data on a three‐variable basis: sites, dominant species and time.

ISSN:0892-7014    

DOI:10.1080/08927018809378101

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The adhesion of the sea anemonesActinia equinaandMetridium senilewas tested on a variety of surfaces, and the force required to remove the anemones related to the surface area of the pedal disc in contact with the substratum. In common with many other marine organisms, anemones were more strongly attached to rough surfaces and those with high free surface energies. Initial measurements suggested that the strength of anemone adhesion was considerably lower than that of comparable intertidal organisms but this was later shown to be an artefact of technique. An improved technique was employed to reduce the incidence of peel during adhesion measurements on Tufnol plates giving tenacity measurements forA. equinaof 4·6 × 105N m−2. The pedal disc secretions of both species stained strongly for proteins and only faintly for acid mucopolysaccharides, showing that proteins play a major role in anemone adhesion.

ISSN:0892-7014    

DOI:10.1080/08927018809378102

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The literature on biofouling in oilfield water systems is reviewed and the implications of such fouling considered. The currently available methods for the detection and control of the causative organisms are also discussed.

ISSN:0892-7014    

DOI:10.1080/08927018809378103

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Growth of bacteria that adhere to surfaces immersed in marine habitats is essential in the formation of fouling biofilms. Observations in a dialysis microchamber revealed that starved cells of the adhesive marinePseudomonasJD8 and the non‐adhesive marineVibrioMH3 undergo cellular growth and reproduction when exposed to surface‐bound stearic acid as the only available energy substrate.VibrioMH3 exhibited cellular growth and began the division process near the surface, but the dividing cells returned to the aqueous phase for the final production of daughter cells. In contrast, dividing cells ofPseudomonasJD8 remained attached to the surface, with the daughter cells slowly migrating across the surface after division. This migration and the subsequent detachment ofPseudomonasJD8 cells from the surface was probably related to changes in the substratum surface free energy after utilisation of the surface‐bound stearic acid. Changes in cell numbers and size distribution ofPseudomonasJD8 andVibrioMH3 in the aqueous phase in the presence of stearic acid coated beads generally reflected the behaviour of the organisms at the surface described above.

ISSN:0892-7014    

DOI:10.1080/08927018809378104

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The musselMytilus galloprovincialishas been studiedin situas a fouling organism in the north‐eastern part of the Adriatic Sea, in waters ranging from relatively clean to those contaminated by pollutants of urban and industrial origin (oil pollution, fish processing plant). Observations were made with artificial substrata (glass, wood, metal, PVC, wooden fishing ships) exposed for 7, 14 and 30 days and from 2 to 14 months. The studies included parameters such as frequency of occurrence, abundance, grade of abundance, dominance, length of valve, cover and biomass; the qualitative degree of pollution was also determined for each site investigated. Mussels prefer the mediolittoral and upper infralittoral zones, slight urban‐industrial pollution of organic origin, cleaner environments (primarily rich in food), shorter time of substratum exposure (up to one month), inert substrata (transparent glass, unprotected wood) and parts of ships protected from stronger water movements. The most unfavourable conditions for mussels include high silting (totally limiting), oil pollution (almost to totally limiting), nutrient‐poor coasts, long time of exposure (substantial fouling competition), toxic coating (particularly for wood), and parts of ships more exposed to high water speed when in motion.

ISSN:0892-7014    

DOI:10.1080/08927018809378105

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0892-7014    

DOI:10.1080/08927018809378099

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor