In situ micropuncture study of pancreatic duct pH

1980 ◽  
Vol 238 (3) ◽  
pp. G263-G268 ◽  
Author(s):  
C. R. Caflisch ◽  
S. Solomon ◽  
W. R. Galey
Keyword(s):  
Chloride Concentration ◽  
Flow Conditions ◽  
Buffer Solutions ◽  
Micropuncture Study ◽  
Glass Membrane ◽  
Rabbit Pancreas ◽  
Alkaline Fluid ◽  
Ph Microelectrodes ◽  
Chloride Concentrations

The pH and chloride concentration in the extralobular duct system of the rabbit pancreas was investigated by using glass-membrane pH microelectrodes and microsampling techniques. The response of pH microelectrodes was compared to that of a pH macroelectrode system in buffer solutions containing common interfering substances and it was found that the electrodes were insensitive to these substances. Final pancreatic juice electrolyte concentrations and osmolality were found to be similar to that observed by others. Under free-flow conditions, a significant pH gradient was found between small extralobular ducts (7.47) and final juice (8.03). This gradient was nearly obliterated on stimulation with secretin. Duct chloride concentrations were found to be similar in all duct sizes and final juice under unstimulated conditions and after stimulation with secretin. It is concluded that glass-membrane pH microelectrodes are reliable and accurate indicators of pH in this system. The present experiments suggest that the entire extralobular ductal system may participate in the secretion of an alkaline fluid.

Road Salt Application in Highland Creek Watershed, Toronto, Ontario - Chloride Mass Balance

2010 ◽  
Vol 45 (4) ◽  
pp. 451-461 ◽  
Author(s):  
Nandana Perera ◽  
Bahram Gharabaghi ◽  
Peter Noehammer ◽  
Bruce Kilgour
Keyword(s):  
Mass Balance ◽  
Management Practices ◽  
Chloride Concentration ◽  
Aquatic Organisms ◽  
Terrestrial Ecosystems ◽  
Road Salt ◽  
Winter Period ◽  
Chloride Mass Balance ◽  
Creek Watershed ◽  
Chloride Concentrations

Abstract Occurrence of increasing chloride concentrations in urban streams of cold climates, mainly due to road salt application, has raised concerns on its adverse effects on aquatic and terrestrial ecosystems. Therefore, there is a need for a better understanding of processes associated with road salt application and subsequent discharge into the environment in order to develop management practices to minimize detrimental effects of chlorides. The chloride mass analysis for the Highland Creek watershed based on four years of hourly monitoring data indicates that approximately 60% of the chlorides applied on the watershed enter streams prior to subsequent salting period, 85% of which occurs during the period between November and March. Contribution of private de-icing operations on chloride mass input within Highland Creek watershed was estimated to be approximately 38%, indicating its significance in overall chloride mass balance. Salt application rates, as well as chloride output in the streams, vary spatially based on land use, influencing chloride concentrations in surface waters. The estimated groundwater chloride concentration of 275 mg/L indicates that some aquatic organisms in Highland Creek would potentially be at risk even outside the winter period under dry weather flow conditions.

Effect of Salinity on Reaeration Coefficient of Receiving Waters

1984 ◽  
Vol 16 (5-7) ◽  
pp. 139-154 ◽  
Author(s):  
Ching-Gung Wen ◽  
Jao-Fuan Kao ◽  
Lawrence K Wang ◽  
Chii Cherng Liaw
Keyword(s):  
Saline Water ◽  
Chloride Concentration ◽  
Practical Method ◽  
Tidal River ◽  
Quality Analysis ◽  
Flow Conditions ◽  
Water Quality Analysis ◽  
Design Engineers ◽  
Reaeration Coefficient ◽  
Receiving Waters

A practical method of determining reaeration coefficients would greatly aid design engineers in determining the degree of wastewater treatment required for a proposed effluent discharge. Many previous tidal river and estuary studies emphasized mainly the effects of flow conditions (such as velocity, water depth, turbulent intensity, hydraulic gradient, etc.) and temperature on stream aeration, and the effect of salts was not seriously considered. In this research a new mathematical model of reaeration coefficient considering the effect of salts has been developed for water quality analysis in tidal rivers and estuaries. The reaeration coefficient in saline water, k2s(day−1, base e) at any chloride concentration C(g/l) and at 20°C, can be expressed byin which k2f is the reaeration coefficient in fresh water at 20°C. The correlation coefficient of k2s/k2f and C is 0.88.

Adherence of platelets to in situ albumin-binding surfaces under flow conditions: role of surface-adsorbed albumin

2012 ◽  
Vol 7 (4) ◽  
pp. 045007 ◽  
Author(s):  
Sanjukta Guha Thakurta ◽  
Robert Miller ◽  
Anuradha Subramanian
Keyword(s):  
Albumin Binding ◽  
Flow Conditions

Infiltration of de-icing road salts in aquifers: the Trois-Rivières-Ouest case, Quebec, Canada

1989 ◽  
Vol 26 (11) ◽  
pp. 2186-2193 ◽  
Author(s):  
Jacques Locat ◽  
Pierre Gélinas
Keyword(s):  
Unsaturated Zone ◽  
Chloride Concentration ◽  
Late Summer ◽  
Linear Source ◽  
Pumping Wells ◽  
Road Salts ◽  
Hydrogeological Investigation ◽  
Spring Snowmelt ◽  
Chloride Concentrations

The results of an extensive hydrogeological investigation of the effects of de-icing road salts on Highway 55 near Trois-Rivières-Ouest indicate that a salt lens with chloride concentrations exceeding 800 mg/L exists below the highway. Maximum chloride concentration at the nearby pumping wells, not exceeding 140 mg/L, is reached only in late summer, whereas the maximum chloride infiltration follows the spring snowmelt. About 1 year's worth of road salts is retained in the unsaturated zone. The salt lens, in the upper part of the aquifer beneath the highway, has developed to a thickness of 8 m and a width of 400 m and constitutes a linear source of salts for the aquifer. The shape of this lens is distorted by the action of the pumping wells, and the lens is partly depleted by the end of the summer. Because of the particular characteristics of the aquifer at the site studied and the exploitation methods, no long-term threat to the water quality is foreseen.

Column Study on the Effect of Nitrate and Chloride on TCE Removal by Granular Iron

2011 ◽  
Vol 356-360 ◽  
pp. 1642-1646
Author(s):  
Xue Qiang Zhu ◽  
Bao Ping Han ◽  
Guo Jun Wu ◽  
Xiao Qing Zhang
Keyword(s):  
Pitting Corrosion ◽  
Nitrate Concentration ◽  
Chloride Concentration ◽  
Inorganic Anions ◽  
Dual Effect ◽  
Column Study ◽  
Granular Iron ◽  
High Chloride ◽  
Chloride Concentrations

The effects of individual inorganic anions (nitrate and chloride) on the reactivity of granular iron were investigated using plexiglass columns packed with granular iron. The results show that TCE removal decreases apparently with increasing nitrate concentration due to competition for reactive sites. Chloride exhibits dual-effect on the TCE removal by Fe0. In the studied condition, the TCE dechlorination is enhanced at the low chloride concentration due to pitting corrosion and is dampened at the high chloride concentrations such as 59.98 and 110.45 mg/L as Cl-.

scholarly journals Application of Novel Machine Learning Techniques for Predicting the Surface Chloride Concentration in Concrete Containing Waste Material

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2297
Author(s):  
Ayaz Ahmad ◽  
Furqan Farooq ◽  
Krzysztof Adam Ostrowski ◽  
Klaudia Śliwa-Wieczorek ◽  
Slawomir Czarnecki
Keyword(s):  
Machine Learning ◽  
Mean Square Error ◽  
Gene Expression Programming ◽  
Chloride Concentration ◽  
Absolute Error ◽  
Chloride Ions ◽  
Machine Learning Techniques ◽  
Extensive Literature ◽  
Mean Square ◽  
Chloride Concentrations

Structures located on the coast are subjected to the long-term influence of chloride ions, which cause the corrosion of steel reinforcements in concrete elements. This corrosion severely affects the performance of the elements and may shorten the lifespan of an entire structure. Even though experimental activities in laboratories might be a solution, they may also be problematic due to time and costs. Thus, the application of individual machine learning (ML) techniques has been investigated to predict surface chloride concentrations (Cc) in marine structures. For this purpose, the values of Cc in tidal, splash, and submerged zones were collected from an extensive literature survey and incorporated into the article. Gene expression programming (GEP), the decision tree (DT), and an artificial neural network (ANN) were used to predict the surface chloride concentrations, and the most accurate algorithm was then selected. The GEP model was the most accurate when compared to ANN and DT, which was confirmed by the high accuracy level of the K-fold cross-validation and linear correlation coefficient (R2), mean absolute error (MAE), mean square error (MSE), and root mean square error (RMSE) parameters. As is shown in the article, the proposed method is an effective and accurate way to predict the surface chloride concentration without the inconveniences of laboratory tests.

Letter to the Editor

PEDIATRICS ◽  
1969 ◽  
Vol 43 (5) ◽  
pp. 905-906
Author(s):  
Aubrey Milunsky
Keyword(s):  
Cystic Fibrosis ◽  
Bone Marrow ◽  
Clinical Presentation ◽  
Pancreatic Insufficiency ◽  
Chloride Concentration ◽  
Letter To The Editor ◽  
Patient Reported ◽  
Sweat Sample ◽  
Chloride Concentrations

The patient reported in the foregoing letter is of particular interest in view of the recent observations on patients with tnisomy 21 and cystic fibrosis. The multiple possibilities that could explain the clinical presentation have no doubt been considered by the authors. However, the description of "hypoplastic thrombocytopenia" and later pancytopenia in this patient, associated with pancreatic insufficiency, leads to the serious consideration of Shwachman's syndrome (pancreatic insufficiency and bone marrow dysfunction). The wide discrepancy between the sodium and chloride concentrations in the sweat reported in their letter indicates that evaporation of water may have occurred from the sweat sample, leading to an apparently higher sodium and chloride concentration.

Sign in / Sign up

Export Citation Format

Share Document