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Showing papers on "Water environment published in 1985"


Journal ArticleDOI
TL;DR: It is indicated that rotaviruses can survive for several days in raw and treated river water thus making recreational and potable waters potential vehicles for the transmission of rotavirus infections.
Abstract: This study was aimed at assessing the role of water as a vehicle for rotavirus spread by determining how well these viruses survive in the water environment. A cell culture adapted strain of human rotavirus subgroup 2, grown in MA-104 cells, was used as a model. Virus survival was tested in the following types of water samples, derived from the Ottawa River, at two different times of the year: (i) raw water (RW), (ii) municipally treated tap water (TW), and (iii) raw water that had been filtered (FW) through a membrane (0.22 μm). The water samples, with approximately 5.0 × 104 plaque-forming units (PFU) of the virus, were held at either 4 or 20 °C and tested for infectious virus over a period of 64 days. The TW samples had a total and free chlorine content of 0.05 and <0.05 mg/L, respectively. The chlorine in these samples was not neutralized before virus contamination. Irrespective of the holding temperature, the virus titre in FW remained essentially unaltered throughout the test period. In TW held at 4...

69 citations


Journal ArticleDOI
TL;DR: In this paper, a wide range of ΔK values were studied using stepped loading techniques on steels with nominal sulphur contents in the range 0.006-0.019%. MnS inclusion distributions were characterized by sulphur printing.

40 citations


Patent
22 May 1985
TL;DR: In this paper, an improved harness belt system employing a cross-chest belt configuration as well as a gross adjustment feature for pre-adjusting the harness assembly straps to substantially approximate the occupant is presented.
Abstract: An improved harness restraint system for a vehicle seat occupant which includes a unique single-point release device having laterally spaced connectors for attachment of shoulder harness straps. The system also includes an improved harness belt system employing a cross-chest belt configuration as well as a gross adjustment feature for pre-adjusting the harness assembly straps to substantially approximate the occupant. The new system also provides diverging lower restraint belts which encircle each leg of the occupant for anti-gravity and crash restraint. The single-point release device also includes an automatic release mechanism which is activated in a water environment.

31 citations


Journal ArticleDOI
TL;DR: As the water quality came within the confidence intervals of the EEC standards for bathing water the adequacy of these standards needs further appraisal.
Abstract: There are certain health risks associated with recreational exposure to bacteriologically polluted water. In this study, 27% (21/77) of swimmers who took part in a snorkel swimming event, experienced gastrointestinal symptoms within 48 hours of entering the untreated water. The incidence of these symptoms was statistically significantly greater than the incidence of such symptoms reported by two control populations (p less than 0.001), but not significantly different to 25% of people who had experienced gastrointestinal symptoms in a previous snorkel event in the same water environment. As the water quality came within the confidence intervals of the EEC standards for bathing water the adequacy of these standards needs further appraisal.

26 citations


Journal ArticleDOI
TL;DR: In this article, a simple procedure for the determination of the effective Young's modulus of rock is presented, which uses the elastic compliance calibration of fracture toughness test specimen geometry, and is measured with various sized three-point bend and compact tension specimens of granite.
Abstract: A simple procedure for the determination of the effective Young's modulus of rock is presented. The method uses the elastic compliance calibration of fracture toughness test specimen geometry. Specimen compliance is measured with various sized three-point bend and compact tension specimens of granite. The experimental results show that the deformation behavior of the granite is significantly nonlinear and the specimen compliance is dependent on the loading level. A sharply notched specimen is successfully used to determine the effective Young's modulus rather than a fatigue precracked one because of the strong effect of fatigue loading on the specimen compliance. The effective Young's modulus evaluated by the compliance method coincides well with the Young's modulus determined from uniaxial tension tests and shows no specimen size or geometry effects. The effect of water environment on the effective Young's modulus is also investigated by this method.

17 citations


Patent
07 Mar 1985
TL;DR: An apparatus for the treatment of patients suffering from lumbar back ailments or the like comprises at least one float body suspended from an overhead support, intended for suspending the patient who is partially submersed in water and subjected to loading from weights, preferably at the hip region as mentioned in this paper.
Abstract: An apparatus for the treatment of patients suffering from lumbar back ailments or the like comprises at least one float body suspended from an overhead support, intended for suspending the patient who is partially submersed in water and subjected to loading from weights, preferably at the hip region. The overhead support consists of a suspension means from which, by means of straps, a vest is suspended, adapted to fit closely about the chest region of the patient and thereby supporting the patient. The straps are attached to the overhead support via a yoke or crossbar having a central, vertical journal that is pivotally mounted at the top of the overhead support. The float body may consist of two elongated, substantially boat-shaped floats, and the overhead support may consist of four downwardly-depending legs attached at the lower ends thereof to the floats and rigidly attached at the upper ends thereof to a top piece which is disposed centrally between the floats and from which the crossbar is supported.

17 citations


Patent
09 Dec 1985
TL;DR: In this paper, an exercise device for use in water includes a flotation member having upper and lower inflatable chambers for surrounding the appendage of a user, and a clamping device is provided for maintaining the securing mechanism in its selected adjustable position about the user's appendage.
Abstract: An exercise device for use in water includes a flotation member having upper and lower inflatable chambers for surrounding the appendage of a user. A mechanism is disposed about the flotation member intermediate the chambers for adjustably securing the device about the user's appendage. Finally, a clamping device is provided for maintaining the securing mechanism in its selected adjustable position about the user's appendage and is releasably movable along the securing mechanism to adjust and tighten the securing mechanism about the flotation member.

16 citations


Journal Article
01 Jan 1985-Water SA
TL;DR: In this paper, the trophic status of 19 South African impoundments was evaluated by using the OECD eutrophication modelling approach for predicting, over the next two decades, the response of the water bodies to nutrient loads.
Abstract: Eutrophication causes serious water quality problems in some South African impoundments, and it is intended that the situation be alleviated by introducing a 1 mg P/l effluent standard in sensitive catchments. An evaluation of the impact of this standard and other phosphate control measures, e.g. the restriction of the phosphate content of detergents, on the trophic sratus of 19 South African impoundments was made by using the OECD eutrophication modelling approach for predicting, over the next two decades, the trophic response of the water bodies to nutrient loads. The predicted percentage time that severe nuisance conditions (chlorophyll concentrations exceeding 30 mg/m) can be expected, was used as criterion of the trophic status of impoundments. Predications showed that the trophic status of five impoundments is likely to remain acceptable until the year 2000 and no eutrophication control is required for them before that rime. The trophic status of a further five impoundments was predicted to be marginal with the result that the effect of the phosphate standard on their trophic status can be expected to be only marginal. The trophic status of the remaining nine impoundments is either unacceptable, or is predicted to be unacceptable by the year 2 000. Although these impoundments are expected to respons to the phosphate standard, an even stricter standard than 1 mg P/l might be necessary in some cases to ensure an acceptable trophic status. A ban on phosphate based detergents is unlikely to succeed in controlling eutrophication. Nevertheless, control of detergent phosphates may play a supporting role in a strategy to reduce phosphate loads on the water environment. The limitations of the OECD eutrophicarion modelling approach, the data base used for the predictions and research priorities, are discussed.

13 citations


Journal ArticleDOI
TL;DR: In this article, the short-term values of the iodine partition coefficient (IPC) were evaluated experimentally by an air/water system over the following ranges of conditions: temperature = 25 to 70/sup 0/C, pH = 5 to 9, and iodine concentration = 10/sup -9/ to 10/Sup -2/ kg iodine/m/sup 3/H/sub 2/O.
Abstract: Short-term values of the iodine partition coefficient (IPC) were evaluated experimentally by an air/water system over the following ranges of conditions: temperature = 25 to 70/sup 0/C, pH = 5 to 9, and iodine concentration = 10/sup -9/ to 10/sup -2/ kg iodine/m/sup 3/ H/sub 2/O. The experimental IPC values are relatively independent of temperature over the indicated range, but show a significant dependence on pH and iodine concentration. In basic solutions the short-term values are several orders of magnitude less than the true equilibrium values; in acid solutions, the differences are much less. These results are useful for predicting the disposition of iodine shortly (i.e., 1 to 10 h) after iodine has been released into an air/water environment.

8 citations


Journal ArticleDOI
TL;DR: In this article, the effectiveness of four water-proofing materials is studied for pressures up to 172.5 MPa (or 25,000 psi), and the pressure effect on the coated gages is smaller than on uncoated gages.
Abstract: This paper is an extension of an earlier study2 of a pressurized water environment of up to 80 MPa. The effectiveness of four water-proofing materials is studied for pressures up to 172.5 MPa (or 25,000 psi). The pressure effect on the coated gages is also investigated. The results indicate that the pressure effect on coated gages is smaller than on uncoated gages. Two pressure-compensation techniques are evaluated. The newly developed self-compensation method, which simultaneously compensates for temperature and pressure effects, is found most effective.

4 citations



01 Jun 1985
TL;DR: In this paper, the synergistic effects of environmental and material variables on stress corrosion cracking (SCC) of Type 304 stainless steel were investigated at 289/sup 0/C by means of constant extension-rate-tensile (CERT) tests at a strain rate of 1 x 10/sup -6//s.
Abstract: Intergranular stress corrosion cracking (IGSCC) of sensitized Type 304 stainless steel (SS) has been a recurrent problem in the high-temperature water environment of boiling-water-reactors (BWRs) over the past two decades. The synergistic effects of environmental and material variables on stress corrosion cracking (SCC) of Type 304 SS were investigated at 289/sup 0/C by means of constant-extension-rate-tensile (CERT) tests at a strain rate of 1 x 10/sup -6//s. Correlations among environmental variables (dissolved oxygen and impurity concentrations, viz., H/sub 2/SO/sub 4/, steady-state open-circuit electro-chemical potential) and the SCC susceptibility parameters have been determined. The extensive results over a wide range of open-circuit corrosion potential conditions were analyzed by a model which accounts for the effects of environmental variables, microstructure (e.g., degree of sensitization) and strain rate. The results are consistent with a slip-dissolution mechanism for SCC. Furthermore, representation of the dependence of corrosion potential and average crack growth rate on the dissolved oxygen concentration of the water by a simple mathematical function, in conjunction with the theoretical model, enables predictions of both strain rate and environmental effects on the SCC susceptibility of sensitized Type 304 SS. 12 refs., 7 figs.


Patent
24 Jun 1985
TL;DR: In this article, a small autoclave about a test piece is used to repeatedly jet high and low temperature pure waters alternatively to the surface of a gauge section thereof to enable testing of thermal fatigue under the pure water environment.
Abstract: PURPOSE:To enable testing of thermal fatigue under the pure water environment by providing a small autoclave about a test piece to repeatedly jet high and low temperature pure waters alternatively to the surface of a gauge section thereof. CONSTITUTION:The capacity of an autoclave 17 is minimized enough to be mounted on a test piece 18 surrounding a gauge section thereof and the heating of pure water is done with small-capacity heaters 5 and 6. Inlet nozzles for inflow of high and low temperature pure waters and output nozzles for outflow thereof are provided to uniformize the temperature distribution in the circumferential direction of the test piece while a reflux water from the autoclave 17 for high temperature pure water is introduced into a heat exchanger 7 for preheating of the low temperature pure water. Thus, a thermal fatigue testing in the pure water environment can be done efficiently in various temperature ranges.

Journal ArticleDOI
TL;DR: In this paper, the role of the pressure test has been examined, throwing emphasis on the importance of effective non-destructive inspection to detect and characterise flaws, and recent developments to improve and validate very high levels of effectiveness of NDT are summarised.

Journal ArticleDOI
TL;DR: Based upon the results observed in this study, it appears that nonambulatory individuals with low fitness levels were able to experience greater cardiopulmonary work outputs when exercising in a water environment.
Abstract: Six handicapped and six nonhandicapped subjects were given exercise tolerance tests on land and in a water environment. The subjects exercised with their arms only and had their cardiopulmonary performance evaluated. Based upon the results observed in this study, it appears that nonambulatory individuals with low fitness levels were able to experience greater cardiopulmonary work outputs when exercising in a water environment. The less severely handicapped individuals displayed similar patterns to those observed in the NH subjects (i.e., no observable pattern) and thus, may not receive as great a benefit as the more severely handicapped. The water environment appears to improve venous return, cardiac output and lung ventilation, which assists the H subjects to be more efficient during exercise.

Journal ArticleDOI
TL;DR: In this article, the tensile fatigue behavior of FRP joints was investigated under low cycle repeated stress, and the effect of the type of overlay plate in the adhesive bonded part and the effects of water environment on fatigue strength were examined.
Abstract: The tensile fatigue behavior of adhesive bonded joint of FRP was investigated under low cycle repeated stress, and the effect of the type of overlay plate in the adhesive bonded part and the effect of water environment on fatigue strength were examined. The specimen used was ortho phthalic acid unsaturated polyester reinforced with glass mat or roving cloth. The mother plate and overlay plate of the specimen were made of the same material. The fatigue testing machine was developed originally by the authors and it was driven by compressed air. The stress cycle was 100cycles/min. constant and the testing temperature was 40°C constant. The following results were obtained from the experiments:(1) The fatigue strength was almost the same for all type joints, when the shearing strength of the adhesive surface area was adopted as the stress amplitude.(2) The strength of adhesive bonded joint was ranked between 1/4 and 1/10 levels of that of the plain specimen.(3) The fatigue strength of adhesive bonded joint was much influenced by water and it was decreased considerably.(4) The formula useful to estimate the fiatgue life was proposed as Eq. (1).

Journal ArticleDOI
TL;DR: The results lead to the suggestion that the mechanism of lethal action of aminoglycosides may operate through interference with the water balance system of the P.aeruginosa.
Abstract: P.aeruginosa proliferates well in a water environment; however, when subjected to high doses of streptomycin or gentamicin, the residual viable bacteria are killed by moderate water dilution of their media. These results lead to the suggestion that the mechanism of lethal action of aminoglycosides may operate through interference with the water balance system of the P.aeruginosa.


Journal ArticleDOI
TL;DR: Data indicate that rotaviruses could survive long enough in the water environment to give water a considerable potential as a vehicle for their spread.

Patent
15 Mar 1985
TL;DR: An apparatus for the treatment of patients suffering trom lumbar back ailments or the like comprises at least one float body (1) suspended from an overhead support (3.4,5,6,7), intended for suspending the patient who is partially submersed in water and subjected to loading from weights (13), preferably at the hip region.
Abstract: An apparatus for the treatment of patients suffering trom lumbar back ailments or the like comprises at least one float body (1) suspended from an overhead support (3.4,5,6,7), intended for suspending the patient who is partially submersed in water and subjected to loading from weights (13), preferably at the hip region. The overhead support consists of a suspension means (2) from which, by emans of straps (9), a vest (10) is suspended, adapted to fit closely about the chest region of the patient and thereby supporting the patient. The straps (9) are attached to the overhead support (2) via a yoke or crossbar (8) having a central, vertical journal that is pivotally mounted at the top (7) of the overhead support. The float body may consist of two elongated, substantially boat-shaped floats (1), and the overhead support may consist of four downwardly-depending legs (3,4,5,6) attached at the lower ends thereof to the floats (1) and rigidly attached at the upper ends thereof to a top piece (7) which is disposed centrally between the floats (1) and from which the crossbar is supported.